U.S. patent application number 14/593696 was filed with the patent office on 2016-02-11 for organic photoelectronic device and image sensor and electronic device.
The applicant listed for this patent is Samsung Electronics Co., Ltd.. Invention is credited to Xavier BULLIARD, Chul Joon HEO, Yong Wan JIN, Gae Hwang LEE, Kwang Hee LEE, Dong-Seok LEEM, Kyung Bae PARK, Sakurai RIE, Ryuichi SATOH, Tadao YAGI, Sung Young YUN.
Application Number | 20160043318 14/593696 |
Document ID | / |
Family ID | 55175042 |
Filed Date | 2016-02-11 |
United States Patent
Application |
20160043318 |
Kind Code |
A1 |
YAGI; Tadao ; et
al. |
February 11, 2016 |
ORGANIC PHOTOELECTRONIC DEVICE AND IMAGE SENSOR AND ELECTRONIC
DEVICE
Abstract
An organic photoelectronic device includes a first electrode and
a second electrode facing each other, and an active layer between
the first electrode and the second electrode and including a first
compound represented by Chemical Formula 1 or 2, and a ratio
between a FWHM of a light absorption curve depending on a
wavelength of the first compound in a solution state and in a thin
film state satisfies the following Relationship Equation 1:
FWHM2/FWHM1<2.5. In the Relationship Equation 1, FWHM1 is a FWHM
of the light absorption curve depending on a wavelength in a
solution state, and FWHM2 is a FWHM of the light absorption curve
depending on a wavelength in a thin film state.
Inventors: |
YAGI; Tadao; (Hwaseong-si,
KR) ; RIE; Sakurai; (Suwon-si, KR) ; LEE;
Kwang Hee; (Yongin-si, KR) ; LEEM; Dong-Seok;
(Hwaseong-si, KR) ; BULLIARD; Xavier;
(Seongnam-si, KR) ; SATOH; Ryuichi; (Numazu-si,
JP) ; PARK; Kyung Bae; (Hwaseong-si, KR) ;
YUN; Sung Young; (Suwon-si, KR) ; LEE; Gae Hwang;
(Seongnam-si, KR) ; JIN; Yong Wan; (Seoul, KR)
; HEO; Chul Joon; (Busan, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Samsung Electronics Co., Ltd. |
Suwon-Si |
|
KR |
|
|
Family ID: |
55175042 |
Appl. No.: |
14/593696 |
Filed: |
January 9, 2015 |
Current U.S.
Class: |
257/40 |
Current CPC
Class: |
H01L 2251/308 20130101;
H01L 51/442 20130101; H01L 51/008 20130101; H01L 51/4253 20130101;
H01L 51/0046 20130101; H01L 27/307 20130101; H01L 51/0078
20130101 |
International
Class: |
H01L 51/00 20060101
H01L051/00; H01L 27/30 20060101 H01L027/30; H01L 51/44 20060101
H01L051/44 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 7, 2014 |
KR |
10-2014-0101908 |
Claims
1. An organic photoelectronic device, comprising: a first electrode
and a second electrode facing each other; and an active layer
between the first electrode and the second electrode, the active
layer including a first compound represented by the following
Chemical Formula 1 or 2: ##STR00018## wherein, in the Chemical
Formula 1 and 2, each of R.sup.1 to R.sup.12 are independently one
of hydrogen and a monovalent organic group, R.sup.1 to R.sup.12 are
independently present or are fused to each other to provide a ring,
R.sup.13 is one of a substituted or unsubstituted C.sub.6 to
C.sub.30 aryl group, a substituted or unsubstituted C.sub.3 to
C.sub.30 heteroaryl group, a substituted or unsubstituted silyl
group, and a combination thereof, and each of R.sup.14 and R.sup.15
are independently one of a substituted or unsubstituted C.sub.6 to
C.sub.30 aryl group, a substituted or unsubstituted C.sub.3 to
C.sub.30 heteroaryl group, and a combination thereof, and a ratio
between a full width at half maximum (FWHM) of a light absorption
curve depending on a wavelength of the first compound in a solution
state and in a thin film state satisfies the following Relationship
Equation 1: FWHM2/FWHM1<2.5 [Relationship Equation 1] wherein,
in the Relationship Equation 1, FWHM1 is the FWHM of the light
absorption curve depending on the wavelength in the solution state,
and FWHM2 is the FWHM of the light absorption curve depending on
the wavelength in the thin film state.
2. The organic photoelectronic device of claim 1, wherein the first
compound selectively absorbs light in a green wavelength
region.
3. The organic photoelectronic device of claim 1, wherein the FWHM
of the light absorption curve of the first compound depending on
the wavelength in the thin film state is less than or equal to
about 70 nm.
4. The organic photoelectronic device of claim 3, wherein the FWHM
of the light absorption curve of the first compound depending on
the wavelength in the thin film state is about 30 nm to about 70
nm.
5. The organic photoelectronic device of claim 1, wherein the first
compound is present in an amorphous state in the active layer.
6. The organic photoelectronic device of claim 1, wherein each of
the R.sup.1 to R.sup.12 of the Chemical Formula 1 or 2 are
independently one of hydrogen, a substituted or unsubstituted
C.sub.1 to C.sub.30 aliphatic hydrocarbon group, a substituted or
unsubstituted C.sub.6 to C.sub.30 aromatic hydrocarbon group, a
substituted or unsubstituted C.sub.1 to C.sub.30 aliphatic
heterocyclic group, a substituted or unsubstituted C.sub.2 to
C.sub.30 aromatic heterocyclic group, a substituted or
unsubstituted C.sub.1 to C.sub.30 alkoxy group, a substituted or
unsubstituted C.sub.1 to C.sub.30 aryloxy group, a thio group, an
alkylthio group, an arylthio group, a cyano group, a
cyano-containing group, a halogen, a halogen-containing group, a
substituted or unsubstituted sulfonyl group, a substituted or
unsubstituted aminosulfonyl group, a substituted or unsubstituted
arylsulfonyl group, and a combination thereof, the R.sup.13 of the
Chemical Formula 1 is one of a substituted or unsubstituted phenyl
group, a substituted or unsubstituted biphenyl group, a substituted
or unsubstituted terphenyl group, a substituted or unsubstituted
naphthyl group, a substituted or unsubstituted anthracenyl group, a
substituted or unsubstituted quinolinyl group, a silyl group
substituted with an alkyl group, a silyl group substituted with an
aryl group, and a combination thereof, and each of the R.sup.14 and
R.sup.15 of the above Chemical Formula 2 are independently one of a
substituted or unsubstituted phenyl group, a substituted or
unsubstituted biphenyl group, a substituted or unsubstituted
terphenyl group, a substituted or unsubstituted naphthyl group, a
substituted or unsubstituted anthracenyl group, a substituted or
unsubstituted quinolinyl group, and a combination thereof.
7. The organic photoelectronic device of claim 1, wherein the
active layer further comprises a second compound being capable of
absorbing light in a visible ray region.
8. The organic photoelectronic device of claim 7, wherein the
second compound includes one of fullerene and a fullerene
derivative.
9. The organic photoelectronic device of claim 7, wherein the
second compound includes one of thiophene and a thiophene
derivative.
10. The organic photoelectronic device of claim 1, wherein the
first electrode and the second electrode are light-transmitting
electrodes.
11. An image sensor comprising the organic photoelectronic device
of claim 1.
12. The image sensor of claim 11, further comprising: a
semiconductor substrate integrated with a plurality of first
photo-sensing devices sensing light in a blue wavelength region and
a plurality of second photo-sensing devices sensing light in a red
wavelength region, wherein the organic photoelectronic device is on
the semiconductor substrate and selectively absorbs light in a
green wavelength region.
13. The image sensor of claim 12, wherein the plurality of first
photo-sensing devices and the plurality of second photo-sensing
devices are stacked in a vertical direction on the semiconductor
substrate.
14. The image sensor of claim 12, further comprising: a color
filter layer between the semiconductor substrate and the organic
photoelectronic device, the color filter layer including a blue
filter selectively absorbing light in a blue wavelength region and
a red filter selectively absorbing light in a red wavelength
region.
15. The image sensor of claim 12, wherein the organic
photoelectronic device selectively absorbing light in the green
wavelength region, a blue photoelectronic device selectively
absorbing light in a blue wavelength region, and a red
photoelectronic device selectively absorbing light in a red
wavelength region are stacked.
16. The image sensor of claim 11, wherein the image sensor has an
average crosstalk value of less than or equal to about 30%.
17. An electronic device comprising the image sensor of claim 11.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to and the benefit of
Korean Patent Application No. 10-2014-0101908 filed in the Korean
Intellectual Property Office on Aug. 7, 2014, the entire contents
of which are incorporated herein by reference.
BACKGROUND
[0002] 1. Field
[0003] Example embodiments relate to an organic photoelectronic
device, an image sensor, and an electronic device.
[0004] 2. Description of the Related Art
[0005] A photoelectronic device converts light into an electrical
signal using photoelectronic effects, and may include a photodiode
and/or a phototransistor. The photoelectronic device may be applied
to an image sensor, a solar cell and/or an organic light emitting
diode.
[0006] An image sensor including a photodiode requires relatively
high resolution and thus a relatively small pixel. At present, a
silicon photodiode is widely used, but the silicon photodiode has a
problem of deteriorated sensitivity and has a relatively small
absorption area due to relatively small pixels. Accordingly, an
organic material that is capable of replacing silicon has been
researched.
[0007] The organic material has a relatively high extinction
coefficient and selectively absorbs light in a particular
wavelength region depending on a molecular structure, and thus may
simultaneously replace a photodiode and a color filter and
resultantly improve sensitivity and contribute to relatively high
integration.
SUMMARY
[0008] Example embodiments provide an organic photoelectronic
device being capable of increasing wavelength selectivity by
improving light absorption characteristics in a thin film
state.
[0009] Example embodiments also provide an image sensor including
the organic photoelectronic device and decreasing crosstalk between
adjacent pixels.
[0010] Example embodiments also provide an electronic device
including the image sensor.
[0011] According to example embodiments, an organic photoelectronic
device includes a first electrode and a second electrode facing
each other, and an active layer between the first electrode and the
second electrode and including a first compound represented by the
following Chemical Formula 1 or 2.
##STR00001##
[0012] In the Chemical Formula 1 and 2, each of R.sup.1 to R.sup.12
are independently one of hydrogen and a monovalent organic group,
each of R.sup.1 to R.sup.12 are independently present or are fused
to each other to provide a ring, R.sup.13 is one of a substituted
or unsubstituted C.sub.6 to C.sub.30 aryl group, a substituted or
unsubstituted C.sub.3 to C.sub.30 heteroaryl group, a substituted
or unsubstituted silyl group, and a combination thereof, and each
of R.sup.14 and R.sup.15 are independently one of a substituted or
unsubstituted C.sub.6 to C.sub.30 aryl group, a substituted or
unsubstituted C.sub.3 to C.sub.30 heteroaryl group, and a
combination thereof, and a ratio between a FWHM (full width at half
maximum) of a light absorption curve depending on a wavelength of
the first compound in a solution state and in a thin film state
satisfies the following Relationship Equation 1:
FWHM2/FWHM1<2.5.
[0013] In the Relationship Equation 1, FWHM1 is the FWHM of the
light absorption curve depending on the wavelength in the solution
state, and FWHM2 is the FWHM of the light absorption curve
depending on the wavelength in the thin film state.
[0014] The first compound may selectively absorb light in a green
wavelength region.
[0015] The FWHM of the light absorption curve of the first compound
depending on the wavelength in the thin film state is less than or
equal to about 70 nm.
[0016] The FWHM of the light absorption curve of the first compound
depending on the wavelength in the thin film state may be about 30
nm to about 70 nm.
[0017] The first compound may be present in an amorphous state in
the active layer.
[0018] Each of the R.sup.1 to R.sup.12 of the Chemical Formula 1
and 2 may independently be one of hydrogen, a substituted or
unsubstituted C.sub.1 to C.sub.30 aliphatic hydrocarbon group, a
substituted or unsubstituted C.sub.6 to C.sub.30 aromatic
hydrocarbon group, a substituted or unsubstituted C.sub.1 to
C.sub.30 aliphatic heterocyclic group, a substituted or
unsubstituted C.sub.2 to C.sub.30 aromatic heterocyclic group, a
substituted or unsubstituted C.sub.1 to C.sub.30 alkoxy group, a
substituted or unsubstituted C.sub.1 to C.sub.30 aryloxy group, a
thio group, an alkylthio group, an arylthio group, a cyano group, a
cyano-containing group, a halogen, a halogen-containing group, a
substituted or unsubstituted sulfonyl group, a substituted or
unsubstituted aminosulfonyl group, a substituted or unsubstituted
arylsulfonyl group, and a combination thereof, the R.sup.13 of the
Chemical Formula 1 may be one of a substituted or unsubstituted
phenyl group, a substituted or unsubstituted biphenyl group, a
substituted or unsubstituted terphenyl group, a substituted or
unsubstituted naphthyl group, a substituted or unsubstituted
anthracenyl group, a substituted or unsubstituted quinolinyl group,
a silyl group substituted with an alkyl group, a silyl group
substituted with an aryl group, and a combination thereof, and each
of the R.sup.14 and R.sup.15 of the above Chemical Formula 2 may
independently be one of a substituted or unsubstituted phenyl
group, a substituted or unsubstituted biphenyl group, a substituted
or unsubstituted terphenyl group, a substituted or unsubstituted
naphthyl group, a substituted or unsubstituted anthracenyl group, a
substituted or unsubstituted quinolinyl group, and a combination
thereof.
[0019] The active layer may further include a second compound being
capable of absorbing light in a visible ray region.
[0020] The second compound may include one of fullerene and a
fullerene derivative.
[0021] The second compound may include one of thiophene and a
thiophene derivative.
[0022] The first electrode and the second electrode may be
light-transmitting electrodes.
[0023] According to example embodiments, an image sensor includes
the organic photoelectronic device.
[0024] The image sensor may include a semiconductor substrate
integrated with a plurality of first photo-sensing devices sensing
light in a blue wavelength region and a plurality of second
photo-sensing devices sensing light in a red wavelength region, and
the organic photoelectronic device may be on the semiconductor
substrate and selectively absorbing light in a green wavelength
region.
[0025] The first photo-sensing device and the second photo-sensing
device may be stacked in a vertical direction on the semiconductor
substrate.
[0026] The image sensor may further include a color filter layer
between the semiconductor substrate and the organic photoelectronic
device, and including a blue filter selectively absorbing light in
a blue wavelength region and a red filter selectively absorbing
light in a red wavelength region.
[0027] The organic photoelectronic device selectively absorbing
light in the green wavelength region, a blue photoelectronic device
selectively absorbing light in a blue wavelength region, and a red
photoelectronic device selectively absorbing light in a red
wavelength region may be stacked.
[0028] The image sensor may have an average crosstalk value of less
than or equal to about 30%.
[0029] According to example embodiments, an electronic device
includes the image sensor.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] FIG. 1 is a cross-sectional view showing an organic
photoelectronic device according to example embodiments,
[0031] FIG. 2 is a cross-sectional view showing an organic
photoelectronic device according to example embodiments,
[0032] FIG. 3 is a schematic top plan view showing an organic CMOS
image sensor according to example embodiments,
[0033] FIG. 4 is a cross-sectional view showing the organic CMOS
image sensor of FIG. 3,
[0034] FIG. 5 is a schematic cross-sectional view showing an
organic CMOS image sensor according to example embodiments,
[0035] FIG. 6 is a schematic top plan view showing an organic CMOS
image sensor according to example embodiments,
[0036] FIG. 7 is a graph showing light absorption characteristics
of the compound according to Synthesis Example 4 and Comparative
Synthesis Example 1 in a solution state,
[0037] FIG. 8 is a graph showing light absorption characteristics
of the compound according to Synthesis Example 4 and Comparative
Synthesis Example 1 in a thin film state, and
[0038] FIG. 9 is a graph showing a relationship between a FWHM and
crosstalk of the image sensors including the organic
photoelectronic devices according to Examples 1 to 9 and
Comparative Examples 1 to 3.
DETAILED DESCRIPTION
[0039] Example embodiments of the present inventive concepts will
hereinafter be described in detail, and may be more easily
performed by those who have common knowledge in the related art.
However, this disclosure may be embodied in many different forms
and is not construed as limited to the example embodiments set
forth herein.
[0040] It will be understood that when an element or layer is
referred to as being "on," "connected to," "coupled to," or
"covering" another element or layer, it may be directly on,
connected to, coupled to, or covering the other element or layer,
or intervening elements or layers may be present. In contrast, when
an element is referred to as being "directly on," "directly
connected to," or "directly coupled to" another element or layer,
there are no intervening elements or layers present. Like numbers
refer to like elements throughout the specification. As used
herein, the term "and/or" includes any and all combinations of one
or more of the associated listed items.
[0041] It will be understood that, although the terms first,
second, third, etc. may be used herein to describe various
elements, components, regions, layers, and/or sections, these
elements, components, regions, layers, and/or sections should not
be limited by these terms. These terms are only used to distinguish
one element, component, region, layer, or section from another
element, component, region, layer, or section. Thus, a first
element, component, region, layer, or section discussed below could
be termed a second element, component, region, layer, or section
without departing from the teachings of the example
embodiments.
[0042] Spatially relative terms, e.g., "beneath," "below," "lower,"
"above," "upper," and the like, may be used herein for ease of
description to describe one element or feature's relationship to
another element(s) or feature(s) as illustrated in the figures. It
will be understood that the spatially relative terms are intended
to encompass different orientations of the device in use or
operation in addition to the orientation depicted in the figures.
For example, if the device in the figures is turned over, elements
described as "below" or "beneath" other elements or features would
then be oriented "above" the other elements or features. Thus, the
term "below" may encompass both an orientation of above and below.
The device may be otherwise oriented (rotated 90 degrees or at
other orientations) and the spatially relative descriptors used
herein interpreted accordingly.
[0043] The terminology used herein is for the purpose of describing
various embodiments only and is not intended to be limiting of the
example embodiments. As used herein, the singular forms "a," "an,"
and "the" are intended to include the plural forms as well, unless
the context clearly indicates otherwise. It will be further
understood that the terms "comprises," "comprising," "includes,"
and/or "including," if used herein, specify the presence of stated
features, integers, steps, operations, elements, and/or components,
but do not preclude the presence or addition of one or more other
features, integers, steps, operations, elements, components, and/or
groups thereof.
[0044] Unless otherwise defined, all terms (including technical and
scientific terms) used herein have the same meaning as commonly
understood by one of ordinary skill in the art. It will be further
understood that terms, including those defined in commonly used
dictionaries, should be interpreted as having a meaning that is
consistent with their meaning in the context of the relevant art
and will not be interpreted in an idealized or overly formal sense
unless expressly so defined herein.
[0045] As used herein, when a definition is not otherwise provided,
the term "substituted" refers to one substituted with a substituent
selected from a halogen (F, Br, Cl or I), a hydroxy group, an
alkoxy group, a nitro group, a cyano group, an amino group, an
azido group, an amidino group, a hydrazino group, a hydrazono
group, a carbonyl group, a carbamyl group, a thiol group, an ester
group, a carboxyl group or a salt thereof, a sulfonic acid group or
a salt thereof, a phosphoric acid or a salt thereof, a C.sub.1 to
C.sub.20 alkyl group, a C.sub.2 to C.sub.20 alkenyl group, a
C.sub.2 to C.sub.20 alkynyl group, a C.sub.6 to C.sub.30 aryl
group, a C.sub.7 to C.sub.30 arylalkyl group, a C.sub.1 to C.sub.4
alkoxy group, a C.sub.1 to C.sub.20 heteroalkyl group, a C.sub.3 to
C.sub.20 heteroarylalkyl group, a C.sub.3 to C.sub.30 cycloalkyl
group, a C.sub.3 to C.sub.15 cycloalkenyl group, a C.sub.6 to
C.sub.15 cycloalkynyl group, a C.sub.2 to C.sub.20 heterocycloalkyl
group, and a combination thereof, instead of hydrogen of a
compound.
[0046] As used herein, when specific definition is not otherwise
provided, the term "hetero" refers to one including 1 to 3
heteroatoms selected from N, O, S, and P.
[0047] In the drawings, the thickness of layers, films, panels,
regions, etc., are exaggerated for clarity. Like reference numerals
designate like elements throughout the specification. It will be
understood that when an element such as a layer, film, region, or
substrate is referred to as being "on" another element, it can be
directly on the other element or intervening elements may also be
present. In contrast, when an element is referred to as being
"directly on" another element, there are no intervening elements
present.
[0048] In the drawings, parts having no relationship with the
description are omitted for clarity of the embodiments, and the
same or similar constituent elements are indicated by the same
reference numerals throughout the specification.
[0049] Hereinafter, an organic photoelectronic device according to
example embodiments is described with reference with the
drawings.
[0050] FIG. 1 is a cross-sectional view of an organic
photoelectronic device according to example embodiments.
[0051] Referring to FIG. 1, an organic photoelectronic device 100
according to example embodiments includes a first electrode 10 and
a second electrode 20, and an active layer 30 interposed between
the first electrode 10 and the second electrode 20.
[0052] One of the first electrode 10 and the second electrode 20 is
an anode and the other is a cathode. At least one of the first
electrode 10 and the second electrode 20 may be a
light-transmitting electrode, and the light-transmitting electrode
may be made of, for example, a transparent conductor (e.g., indium
tin oxide (ITO) or indium zinc oxide (IZO)), or a metal thin layer
of a thin monolayer or multilayer. When one of the first electrode
10 and the second electrode 20 is a non-light-transmitting
electrode, the one of the first electrode 10 and the second
electrode 20 may be made of, for example, an opaque conductor
(e.g., aluminum (Al)).
[0053] For example, the first electrode 10 and the second electrode
20 may be light-transmitting electrodes.
[0054] The active layer 30 includes a p-type semiconductor and an
n-type semiconductor to form a pn junction, and absorbs external
light to generate excitons and then separates the generated
excitons into holes and electrons.
[0055] The active layer 30 includes a first compound as a p-type
semiconductor or an n-type semiconductor.
[0056] The first compound is a light-absorbing body being capable
of selectively absorbing light in a predetermined or given
wavelength region of a visible ray region. For example, the first
compound may selectively absorb light in a green wavelength region,
and may have, for example, a maximum absorption wavelength
(.lamda..sub.max) of about 500 nm to about 600 nm and an energy
bandgap of about 2.0 to about 2.5 eV.
[0057] Wavelength selectivity for absorbing light in a
predetermined or given wavelength region of a visible ray region
may be indicated by a FWHM. Herein, the FWHM is a width of a
wavelength corresponding to a half of a maximum absorption point.
As used herein, when specific definition is not otherwise provided,
it may be defined by absorbance measured by UV-Vis spectroscopy. A
smaller FWHM indicates selective absorption of light in a narrow
wavelength region and high wavelength selectivity.
[0058] A ratio of FWHMs of the light absorption curve depending on
a wavelength of the first compound in a solution state and in a
thin film state may satisfy the following Relationship Equation
1.
FWHM2/FWHM1<2.5 [Relationship Equation 1]
[0059] In the Relationship Equation 1,
[0060] FWHM1 is a FWHM of the light absorption curve depending on a
wavelength in a solution state, and
[0061] FWHM2 is a FWHM of the light absorption curve depending on a
wavelength in a thin film state.
[0062] The thin film may be formed by vacuum deposition.
[0063] The Relationship Equation 1 indicates the FWHM variation in
a thin film state relative to the FWHM in a solution state of the
first compound.
[0064] By satisfying the Relationship Equation 1, the light
absorption characteristics of the first compound in a solution
state are not significantly different from the light absorption
characteristics of the first compound in a thin film state, and the
light absorption characteristics of the first compound in a thin
film state are not degraded. Accordingly, when the first compound
is applied to the active layer 30 of the organic photoelectronic
device, the first compound may ensure wavelength selectivity for a
predetermined or given wavelength region.
[0065] For example, the ratio between a FWHM of a light absorption
curve depending on a wavelength of the first compound in a solution
state and in a thin film state may satisfy the following
Relationship Equation 1A.
1.0.ltoreq.FWHM2/FWHM1<2.5 [Relationship Equation 1A]
[0066] For example, a ratio between a FWHM of a light absorption
curve depending on a wavelength of the first compound in a solution
state and in a thin film state may satisfy the following
Relationship Equation 1B.
1.3<FWHM2/FWHM1<2.5 [Relationship Equation 1B]
[0067] For example, a ratio between a FWHM of a light absorption
curve depending on a wavelength of the first compound in a solution
state and in a thin film state may satisfy the following
Relationship Equation 1 C.
1.5<FWHM2/FWHM1.ltoreq.2.3 [Relationship Equation 1C]
[0068] The first compound may have a FWHM of less than or equal to
about 70 nm in the light absorption curve depending on a wavelength
in a thin film state. Within the range, the first compound may have
a FWHM of about 30 nm to about 70 nm in the light absorption curve
depending on a wavelength in a thin film state.
[0069] The first compound may be present in an amorphous state in a
thin film state, and for example, about 30% to about 100% of the
first compound may be present in an amorphous state in a thin film
state, for another example, about 50 to about 100% of the first
compound may be present in an amorphous state in a thin film state,
and for another example, about 70% to about 100% of the first
compound may be present in an amorphous state in a thin film
state.
[0070] The first compound is present in an amorphous state in a
thin film state, and thereby response speed and dark current
characteristics may be ensured and improved performance of an image
sensor may be provided when the organic photoelectronic device is
applied to a device such as an image sensor.
[0071] The amorphous state may be, for example, confirmed with an
AFM (Atomic Force Microscope) and/or by XRD (X-ray
diffraction).
[0072] The first compound may selectively absorb light in a green
wavelength region, and may be, for example, represented by the
following Chemical Formula 1 or 2.
##STR00002##
[0073] In the Chemical Formula 1 and 2,
[0074] each of R.sup.1 to R.sup.12 are independently one of
hydrogen and a monovalent organic group,
[0075] each of R.sup.1 to R.sup.12 are independently present or are
fused to each other to provide a ring,
[0076] R.sup.13 is one of a substituted or unsubstituted C.sub.6 to
C.sub.30 aryl group, a substituted or unsubstituted C.sub.3 to
C.sub.30 heteroaryl group, a substituted or unsubstituted silyl
group, and a combination thereof, and
[0077] each of R.sup.14 and R.sup.15 are independently one of a
substituted or unsubstituted C.sub.6 to C.sub.30 aryl group, a
substituted or unsubstituted C.sub.3 to C.sub.30 heteroaryl group,
and a combination thereof.
[0078] For example, the R.sup.1 to R.sup.12 of the Chemical Formula
1 or 2 may independently be one of hydrogen, a substituted or
unsubstituted C.sub.1 to C.sub.30 aliphatic hydrocarbon group, a
substituted or unsubstituted C.sub.6 to C.sub.30 aromatic
hydrocarbon group, a substituted or unsubstituted C.sub.1 to
C.sub.30 aliphatic heterocyclic group, a substituted or
unsubstituted C.sub.2 to C.sub.30 aromatic heterocyclic group, a
substituted or unsubstituted C.sub.1 to C.sub.30 alkoxy group, a
substituted or unsubstituted C.sub.1 to C.sub.30 aryloxy group, a
thio group, an alkylthio group, an arylthio group, a cyano group, a
cyano-containing group, a halogen, a halogen-containing group, a
substituted or unsubstituted sulfonyl group, a substituted or
unsubstituted aminosulfonyl group, a substituted or unsubstituted
arylsulfonyl group, and a combination thereof.
[0079] For example, the R.sup.13 of the Chemical Formula 1 may be
one of a substituted or unsubstituted phenyl group, a substituted
or unsubstituted biphenyl group, a substituted or unsubstituted
terphenyl group, a substituted or unsubstituted naphthyl group, a
substituted or unsubstituted anthracenyl group, a substituted or
unsubstituted quinolinyl group, a silyl group substituted with an
alkyl group, a silyl group substituted with an aryl group, and a
combination thereof.
[0080] For example, each of the R.sup.14 and R.sup.15 of the
Chemical Formula 2 may independently be one of a substituted or
unsubstituted phenyl group, a substituted or unsubstituted biphenyl
group, a substituted or unsubstituted terphenyl group, a
substituted or unsubstituted naphthyl group, a substituted or
unsubstituted anthracenyl group, a substituted or unsubstituted
quinolinyl group, and a combination thereof.
[0081] The first compound represented by the Chemical Formula 1 or
2 includes a planar backbone including bonds of boron (B), nitrogen
(N), and carbon (C), and an axis substituent of B--O--R.sup.13 or
B--O--NR.sup.14R.sup.15 stretched out in a vertical direction
relative to the planar backbone. Through such a structure,
molecular aggregation of the first compound may be reduced and/or
inhibited, and thus film quality in a thin film state may be
improved. Accordingly, the light absorption characteristics of the
first compound in a solution state are not significantly different
from the light absorption characteristics of the first compound in
a thin film state, and the light absorption characteristics of the
first compound in a thin film state are not degraded.
[0082] The first compound may have a molecular weight of greater
than or equal to about 500. Within the range, the first compound
may, for example, have a molecular weight of about 500 to about
1200, and for another example, about 500 to 800. When the first
compound has a molecular weight within the range, the crystallinity
of the first compound may be inhibited and thermal decomposition
during formation of a thin film by deposition may be prevented or
reduced.
[0083] The first compound may be included as a p-type semiconductor
or an n-type semiconductor. When the first compound is included as
a p-type semiconductor, a second compound that is an n-type
semiconductor may be further included, and when the first compound
is included as an n-type semiconductor, a second compound that is a
p-type semiconductor may be further included.
[0084] The second compound is not particularly limited, and may be
a light-absorbing material, for example, a material being capable
of absorbing a part or a whole of a visible ray region of about 380
nm to about 780 nm. The second compound may be formed in a thin
film by deposition such as vacuum deposition, with the first
compound.
[0085] For example, the second compound may be fullerene, e.g.,
C.sub.60 or a fullerene derivative. For example, the second
compound may be thiophene or a thiophene derivative.
[0086] The thiophene derivative may be, for example, represented by
the following Chemical Formula 3 or Chemical Formula 4, but is not
limited thereto.
##STR00003##
[0087] In the Chemical Formula 3 or 4,
[0088] each of T.sup.1, T.sup.2, and T.sup.3 are an aromatic ring
including a substituted or unsubstituted thiophene moiety,
[0089] each of T.sup.1, T.sup.2, and T.sup.3 are independently
present or are fused to each other,
[0090] each of X.sup.3 to X.sup.8 are independently one of
hydrogen, a substituted or unsubstituted C.sub.1 to C.sub.30 alkyl
group, a substituted or unsubstituted C.sub.6 to C.sub.30 aryl
group, a substituted or unsubstituted C.sub.3 to C.sub.30
heterocyclic group, a cyano group, and a combination thereof,
and
[0091] EWG.sup.1 and EWG.sup.2 are independently an electron
withdrawing group.
[0092] For example, in the Chemical Formula 3, at least one of
X.sup.3 to X.sup.8 may be an electron withdrawing group.
[0093] For example, in the Chemical Formula 3, at least one of
X.sup.3 to X.sup.8 may be a cyano group.
[0094] For example, in the Chemical Formula 3, T.sup.1, T.sup.2,
and T.sup.3 may be selected from groups listed in the following
Group 1.
##STR00004##
[0095] In the Group 1,
[0096] each of R.sup.16 to R.sup.31 are independently one of
hydrogen, a substituted or unsubstituted C.sub.1 to C.sub.30 alkyl
group, a substituted or unsubstituted C.sub.6 to C.sub.30 aryl
group, a substituted or unsubstituted C.sub.3 to C.sub.30
heteroaryl group, and a combination thereof.
[0097] For example, the thiophene derivative may be one of
compounds represented by the following Chemical Formulae 3a to 3c,
4a, and 4b.
##STR00005##
[0098] Herein, each of R.sup.32 to R.sup.35 are independently one
of hydrogen, a substituted or unsubstituted C.sub.1 to C.sub.30
alkyl group, a substituted or unsubstituted C.sub.6 to C.sub.30
aryl group, a substituted or unsubstituted C.sub.3 to C.sub.30
heteroaryl group, and a combination thereof, and EWG.sup.1 and
EWG.sup.2 are independently an electron withdrawing group. The
electron withdrawing group may be, for example, a cyano group or a
cyano-containing group.
[0099] The active layer 30 may be a single layer or a multilayer.
The active layer 30 may be, for example, an intrinsic layer (I
layer), a p-type layer/I layer, an I layer/n-type layer, a p-type
layer/I layer/n-type layer and/or a p-type layer/n-type layer.
[0100] The intrinsic layer (I layer) may include the p-type
semiconductor compound and the n-type semiconductor compound in a
ratio of about 1:100 to about 100:1. The compounds may be included
in a ratio ranging from about 1:50 to about 50:1 within the range,
specifically, about 1:10 to about 10:1, and more specifically,
about 1:1. When the p-type and n-type semiconductors have a
composition ratio within the range, an exciton may be effectively
produced and a pn junction may be effectively formed.
[0101] The p-type layer may include the p-type semiconductor
compound, and the n-type layer may include the n-type semiconductor
compound.
[0102] The active layer 30 may have a thickness of about 1 nm to
about 500 nm, and specifically, about 5 nm to about 300 nm. When
the active layer 30 has a thickness within the range, the active
layer may effectively absorb light, effectively separate holes from
electrons, and deliver them, thereby effectively improving
photoelectronic conversion efficiency. An optimal or desired
thickness of a thin film may be, for example, determined by an
absorption coefficient of the active layer 30, and may be, for
example, a thickness being capable of absorbing light of at least
about 70% or more, for example about 80% or more, and for another
example about 90%.
[0103] In the organic photoelectronic device 100, when light enters
from the first electrode 10 and/or second electrode 20, and when
the active layer 30 absorbs light having a predetermined or given
wavelength region, excitons may be produced from the inside. The
excitons are separated into holes and electrons in the active layer
30, and the separated holes are transported to an anode that is one
of the first electrode 10 and second electrode 20, while the
separated electrons are transported to the cathode that is the
other of and the first electrode 10 and second electrode 20 so as
to flow a current in the organic photoelectronic device.
[0104] Hereinafter, an organic photoelectronic device according to
example embodiments is described.
[0105] FIG. 2 is a cross-sectional view showing an organic
photoelectronic device according to example embodiments.
[0106] Referring to FIG. 2, an organic photoelectronic device 200
according to example embodiments includes a first electrode 10 and
a second electrode 20 facing each other, and an active layer 30
interposed between the first electrode 10 and the second electrode
20, like the example embodiment illustrated in FIG. 1.
[0107] However, the organic photoelectronic device 200 according to
example embodiments further includes charge auxiliary layers 40 and
50 between the first electrode 10 and the active layer 30, and the
second electrode 20 and the active layer 30, unlike the example
embodiment illustrated in FIG. 1. The charge auxiliary layers 40
and 50 may facilitate the transfer of holes and electrons separated
from the active layer 30, so as to increase efficiency.
[0108] The charge auxiliary layers 40 and 50 may be at least one
selected from a hole injection layer (HIL) for facilitating hole
injection, a hole transport layer (HTL) for facilitating hole
transport, an electron blocking layer (EBL) for preventing or
inhibiting electron transport, an electron injection layer (EIL)
for facilitating electron injection, an electron transport layer
(ETL) for facilitating electron transport, and a hole blocking
layer (HBL) for preventing or inhibiting hole transport.
[0109] The charge auxiliary layers 40 and 50 may include, for
example, an organic material, an inorganic material, or an
organic/inorganic material. The organic material may be an organic
compound having hole or electron characteristics, and the inorganic
material may be, for example, a metal oxide, e.g., molybdenum
oxide, tungsten oxide and/or nickel oxide.
[0110] The hole transport layer (HTL) may include one selected
from, for example,
poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)
(PEDOT:PSS), polyarylamine, poly(N-vinylcarbazole), polyaniline,
polypyrrole, N,N,N',N'-tetrakis(4-methoxyphenyl-benzidine (TPD),
4-bis[N-(1-naphthyl)-N-phenyl-amino]biphenyl (.alpha.-NPD),
m-MTDATA, 4,4',4''-tris(N-carbazolyl)-triphenylamine (TCTA), and a
combination thereof, but is not limited thereto.
[0111] The electron blocking layer (EBL) may include one selected
from, for example,
poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)
(PEDOT:PSS), polyarylamine, poly(N-vinylcarbazole), polyaniline,
polypyrrole, N,N,N',N'-tetrakis(4-methoxyphenyl)-benzidine (TPD),
4-bis[N-(1-naphthyl)-N-phenyl-amino]biphenyl (.alpha.-NPD),
m-MTDATA, 4,4',4''-tris(N-carbazolyl)-triphenylamine (TCTA), and a
combination thereof, but is not limited thereto.
[0112] The electron transport layer (ETL) may include one selected
from, for example, 1,4,5,8-naphthalene-tetracarboxylic dianhydride
(NTCDA), bathocuproine (BCP), LiF, Alq.sub.3, Gaq.sub.3, Inq.sub.3,
Znq.sub.2, Zn(BTZ).sub.2, BeBq.sub.2, and a combination thereof,
but is not limited thereto.
[0113] The hole blocking layer (HBL) may include one selected from,
for example, 1,4,5,8-naphthalene-tetracarboxylic dianhydride
(NTCDA), bathocuproine (BCP), LiF, Alq.sub.3, Gaq.sub.3, Inq.sub.3,
Znq.sub.2, Zn(BTZ).sub.2, BeBq.sub.2, and a combination thereof,
but is not limited thereto.
[0114] Either one of the charge auxiliary layers 40 and 50 may be
omitted.
[0115] The organic photoelectronic device may be applied to various
fields, for example a solar cell, an image sensor, a
photo-detector, a photo-sensor, and an organic light emitting diode
(OLED), but is not limited thereto.
[0116] Hereinafter, an example of an image sensor including the
organic photoelectronic device is described referring to drawings.
As an example of an image sensor, an organic CMOS image sensor is
described.
[0117] FIG. 3 is a schematic top plan view of an organic CMOS image
sensor according to example embodiments, and FIG. 4 is a
cross-sectional view of the organic CMOS image sensor of FIG.
3.
[0118] Referring to FIGS. 3 and 4, an organic CMOS image sensor 300
according to example embodiments includes a semiconductor substrate
110 integrated with photo-sensing devices 50B and 50R, a
transmission transistor (not shown), a charge storage device 55, a
lower insulation layer 60, a color filter layer 70, an upper
insulation layer 80, and an organic photoelectronic device 100.
[0119] The semiconductor substrate 110 may be a silicon substrate,
and is integrated with the photo-sensing device 50, the
transmission transistor, and the charge storage device 55. The
photo-sensing devices 50R and 50B may be photodiodes.
[0120] The photo-sensing devices 50B and 50R, the transmission
transistor, and/or the charge storage device 55 may be integrated
in each pixel, and as shown in the drawing, the photo-sensing
devices 50B and 50R may be included in a blue pixel and a red pixel
and the charge storage device 55 may be included in a green
pixel.
[0121] The photo-sensing devices 50B and 50R sense light, the
information sensed by the photo-sensing devices may be transferred
by the transmission transistor, the charge storage device 55 is
electrically connected with the organic photoelectronic device 100,
and the information of the charge storage device 55 may be
transferred by the transmission transistor.
[0122] In drawings, the photo-sensing devices 50B and 50R are, for
example, arranged in parallel without limitation, and the blue
photo-sensing device 50B and the red photo-sensing device 50R may
be stacked in a vertical direction.
[0123] A metal wire (not shown) and a pad (not shown) are formed on
the semiconductor substrate 110. In order to decrease signal delay,
the metal wire and pad may be made of a metal having relatively low
resistivity, for example, aluminum (Al), copper (Cu), silver (Ag),
and alloys thereof, but are not limited thereto. Further, it is not
limited to the structure, and the metal wire and pad may be
positioned under the photo-sensing devices 50B and 50R.
[0124] The lower insulation layer 60 is formed on the metal wire
and the pad. The lower insulation layer 60 may be made of an
inorganic insulating material, e.g., a silicon oxide and/or a
silicon nitride, or a low dielectric constant (low K) material,
e.g., SiC, SiCOH, SiCO, and SiOF. The lower insulation layer 60 has
a trench exposing the charge storage device 55. The trench may be
filled with fillers.
[0125] The color filter layer 70 is formed on the lower insulation
layer 60. The color filter layer 70 includes a blue filter 70B
formed in the blue pixel and a red filter 70R filled in the red
pixel. In example embodiments, a green filter is not included, but
a green filter may be further included.
[0126] The color filter layer 70 may be omitted. For example, when
the blue photo-sensing device 50B and the red photo-sensing device
50R are stacked in a vertical direction, the blue photo-sensing
device 50B and the red photo-sensing device 50R may selectively
absorb light in each wavelength region depending on their stack
depth, and the color filter layer 70 may not be equipped.
[0127] The upper insulation layer 80 is formed on the color filter
layer 70. The upper insulation layer 80 eliminates a step caused by
the color filter layer 70 and smoothes the surface. The upper
insulation layer 80 and the lower insulation layer 60 may include a
contact hole (not shown) exposing a pad, and a through-hole 85
exposing the charge storage device 55 of the green pixel.
[0128] The organic photoelectronic device 100 is formed on the
upper insulation layer 80. The organic photoelectronic device 100
includes the first electrode 10, the active layer 30, and the
second electrode 120 as described above.
[0129] The first electrode 10 and the second electrode 20 may be
transparent electrodes, and the active layer 30 is the same as
described above. The active layer 30 selectively absorbs light in a
green wavelength region and replaces a color filter of a green
pixel.
[0130] When light enters from the second electrode 20, the light in
a green wavelength region may be mainly absorbed in the active
layer 30 and photoelectronically converted, while the light in the
rest of the wavelength region passes through first electrode 10 and
may be sensed in the photo-sensing devices 50B and 50R.
[0131] As described above, the organic photoelectronic devices
selectively absorbing light in a green wavelength region are
stacked and thereby a size of an image sensor may be decreased and
a down-sized image sensor may be realized.
[0132] As described above, the first compound represented by the
above Chemical Formula 1 as a p-type or n-type semiconductor
compound is prevented or reduced from being aggregated in a thin
film state, and light absorption characteristics depending on a
wavelength may be maintained. Accordingly, green wavelength
selectivity may be maintained as it is and crosstalk caused by
unnecessary absorption light in a wavelength region except green
may be decreased while increasing sensitivity.
[0133] In FIG. 4, the organic photoelectronic device 100 of FIG. 1
is included, but it is not limited thereto, and thus the organic
photoelectronic device 200 of FIG. 2 may be applied in the same
manner.
[0134] FIG. 5 is a schematic cross-sectional view showing an
organic CMOS image sensor 400 according to example embodiments.
[0135] The organic CMOS image sensor 400 according to example
embodiments includes a semiconductor substrate 110 integrated with
photo-sensing devices 50B and 50R, a transmission transistor (not
shown), a charge storage device 55, an upper insulation layer 80,
and an organic photoelectronic device 100, like the example
embodiment illustrated in FIG. 4.
[0136] However, the organic CMOS image sensor 300 according to
example embodiments includes the blue photo-sensing device 50B and
the red photo-sensing device 50R that are stacked, and does not
include a color filter layer 70, unlike the example embodiment
illustrated in FIG. 4. The blue photo-sensing device 50B and the
red photo-sensing device 50R are electrically connected with the
charge storage device (not shown), and the information of the
charge storage device 55 may be transferred by the transmission
transistor. The blue photo-sensing device 50B and the red
photo-sensing device 50R may selectively absorb light in each
wavelength region depending on a stack depth.
[0137] As described above, the organic photoelectronic devices
selectively absorbing light in a green wavelength region are
stacked and the red photo-sensing device and the blue photo-sensing
device are stacked, and thereby a size of an image sensor may be
decreased and a down-sized image sensor may be realized. As
described above, the organic photoelectronic device 100 has
improved green wavelength selectivity, and crosstalk caused by
unnecessary absorption light in a wavelength region except green
may be decreased while increasing sensitivity.
[0138] In FIG. 5, the organic photoelectronic device 100 of FIG. 1
is included, but it is not limited thereto, and thus the organic
photoelectronic device 200 of FIG. 2 may be applied in the same
manner.
[0139] FIG. 6 is a schematic top plan view of an organic CMOS image
sensor according to example embodiments.
[0140] The organic CMOS image sensor according to example
embodiments includes a green photoelectronic device selectively
absorbing light in a green wavelength region, a blue
photoelectronic device selectively absorbing light in a blue
wavelength region, and a red photoelectronic device selectively
absorbing light in a green wavelength region and that are
stacked.
[0141] In the drawing, the red photoelectronic device, the green
photoelectronic device, and the blue photoelectronic device are
sequentially stacked, but the stack order may be changed without
limitation.
[0142] The green photoelectronic device may be the above organic
photoelectronic device 100, the blue photoelectronic device may
include electrodes facing each other and an active layer interposed
therebetween and including an organic material selectively
absorbing light in a blue wavelength region, and the red
photoelectronic device may include electrodes facing each other and
an active layer interposed therebetween and including an organic
material selectively absorbing light in a red wavelength
region.
[0143] As described above, the organic photoelectronic device
selectively absorbing light in a red wavelength region, the organic
photoelectronic device selectively absorbing light in a green
wavelength region, and the organic photoelectronic device
selectively absorbing light in a blue wavelength region are
stacked, and thereby a size of an image sensor may be decreased and
a down-sized image sensor may be realized.
[0144] The image sensor may be applied to various electronic
devices, for example, a mobile phone and/or a digital camera, but
is not limited thereto.
[0145] Hereinafter, the present disclosure is illustrated in more
detail with reference to examples. However, these are examples, and
the present disclosure is not limited thereto.
Preparation of First Compound
SYNTHESIS EXAMPLE 1
##STR00006##
[0147] 10.0 g of boron subphthalocyanine chloride (Aldrich) and
21.3 g of pentafluorophenol (Aldrich Corporation) are heated and
refluxed in 150 ml of dry toluene for 15 hours. Subsequently, the
reaction solution is concentrated under a reduced pressure and
purified using silica gel column chromatography to obtain the
compound represented by the Chemical Formula A.
SYNTHESIS EXAMPLE 2
##STR00007##
[0149] The compound represented by the Chemical Formula B is
synthesized according to the same method as Synthesis Example 1,
except that 6.6 g of 1-naphthol (Aldrich Corporation) is used
instead of pentafluorophenol.
SYNTHESIS EXAMPLE 3
##STR00008##
[0151] The compound represented by the Chemical Formula C is
synthesized according to the same method as Synthesis Example 1,
except that 6.6 g of 2-naphthol (Aldrich Corporation) is used
instead of pentafluorophenol.
SYNTHESIS EXAMPLE 4
##STR00009##
[0153] The compound represented by the Chemical Formula D is
synthesized according to the same method as Synthesis Example 1,
except that 7.9 g of 4-phenylphenol (Aldrich Corporation) is used
instead of pentafluorophenol.
SYNTHESIS EXAMPLE 5
##STR00010##
[0155] The compound represented by the Chemical Formula E is
synthesized according to the same method as Synthesis Example 1,
except that 7.9 g of 3-phenylphenol (Aldrich Corporation) is used
instead of pentafluorophenol.
SYNTHESIS EXAMPLE 6
##STR00011##
[0157] 10.0 g of boron subphthalocyanine chloride (Aldrich
Corporation), 7.9 g of diphenylamine (Aldrich Corporation), and 7.4
g of silver trifluoromethanesulfonate (Dong Kyung Co., Ltd.) are
heated and refluxed in 150 ml of dry toluene for 15 hours. 200 ml
of dichloromethane is added thereto, the solution is filtered, and
the filtrated solution is concentrated under pressure and purified
using silica gel column chromatography to obtain a compound F.
SYNTHESIS EXAMPLE 7
##STR00012##
[0159] The compound represented by the Chemical Formula G is
synthesized according to the same method as Synthesis Example 6,
except that 6.8 g of 8-quinolinol (Aldrich Corporation) is used
instead of diphenylamine.
SYNTHESIS EXAMPLE 8
##STR00013##
[0161] 20.0 g of boron subphthalocyanine chloride (Aldrich
Corporation), 32.0 g of triphenylsilanol (Dong Kyung Co., Ltd.),
and 14.8 g of silver trifluoromethanesulfonate (Dong Kyung Co.,
Ltd.) are heated and refluxed in 150 ml of dry toluene for 15
hours. 200 ml of methylene chloride is added thereto, the solution
is filtered, and the filtrated solution is concentrated under
pressure and purified using silica gel column chromatography to
obtain a compound H.
SYNTHESIS EXAMPLE 9
##STR00014##
[0163] The compound represented by the Chemical Formula I is
synthesized according to the same method as Synthesis Example 8,
except that 23.8 g of potassium trimethyl siloxide (Aldrich
Corporation) is used instead of triphenylsilanol and a reaction
temperature is 50.degree. C.
COMPARATIVE SYNTHESIS EXAMPLE 1
[0164] The compound (sublimation purified product, Lumtec)
represented by the following Chemical Formula J is prepared.
##STR00015##
COMPARATIVE SYNTHESIS EXAMPLE 2
[0165] The compound represented by the following Chemical Formula K
is prepared according to Angewandte Chemie, International Edition
Volume 50 Issue 15 Pages 3506-3509.
##STR00016##
COMPARATIVE SYNTHESIS EXAMPLE 3
[0166] The compound represented by the Chemical Formula L is
synthesized according to the same method as Synthesis Example 6,
except that 50 ml of methanol (Aldrich Corporation) is used instead
of diphenylamine.
##STR00017##
Evaluation I
Evaluation 1: Light Absorption Characteristics
[0167] Light absorption characteristics of the compounds according
to Synthesis Examples 1 to 9 and Comparative Synthesis Examples 1
to 3 are evaluated depending on a wavelength.
[0168] The light absorption characteristics are evaluated in both
solution and thin film states of the compounds.
[0169] The light absorption characteristics in a solution state are
evaluated by dissolving each compound according to Synthesis
Examples 1 to 9 and Comparative Synthesis Examples 1 to 3 in a
concentration of 1.0.times.10.sup.-5 mol/L in toluene.
[0170] The light absorption characteristics in a thin film state
are evaluated by thermally evaporating each compound according to
Synthesis Examples 1 to 9 and Comparative Synthesis Examples 1 to 3
at a speed of 0.5-1.0 .ANG./s under high vacuum (<10.sup.-7
Torr) to respectively form 70 nm-thick thin films and radiating
ultraviolet (UV)-visible rays (UV-Vis) on the thin films with a
Cary 5000 UV spectroscope (Varian Inc.).
[0171] The results are provided in FIGS. 7 and 8 and Table 1.
[0172] FIG. 7 is a graph showing light absorption characteristics
of the compound according to Synthesis Example 4 and Comparative
Synthesis Example 1 in a solution state, and FIG. 8 is a graph
showing light absorption characteristics of the compound according
to Synthesis Example 4 and Comparative Synthesis Example 1 in a
thin film state.
TABLE-US-00001 TABLE 1 FWHM .lamda..sub.max (nm) FWHM1 FWHM2 solu-
thin (solu- (thin FWHM2/ tion film tion, nm) film, nm) FWHM1 State
Synthesis 564 581 28 48 1.7 Amor- Example 1 phous Synthesis 563 579
30 62 2.1 Amor- Example 2 phous Synthesis 563 580 29 63 2.2 Amor-
Example 3 phous Synthesis 563 579 28 62 2.2 Amor- Example 4 phous
Synthesis 563 580 29 65 2.2 Amor- Example 5 phous Synthesis 567 583
36 61 1.7 Amor- Example 6 phous Synthesis 563 581 29 65 2.2 Amor-
Example 7 phous Synthesis 562 575 29 46 1.6 Amor- Example 8 phous
Synthesis 561 575 29 63 2.2 Amor- Example 9 phous Comparative 565
587 23 81 3.5 -- Synthesis Example 1 Comparative 562 582 29 83 2.9
-- Synthesis Example 2 Comparative 561 581 28 75 2.7 -- Synthesis
Example 3
[0173] Referring to FIG. 7 and Table 1, the compounds according to
Synthesis Examples 1 to 9 show similar light absorption
characteristics to those of the Comparative Synthesis Examples 1 to
3 in a solution state.
[0174] On the contrary, referring to FIG. 8 and Table 1, the
compounds according to Synthesis Examples 1 to 9 show a
significantly narrower FWHM compared with the compounds according
to Comparative Synthesis Examples 1 to 2. For example, the
compounds Synthesis Examples 1 to 9 have FWHM's of less than or
equal to about 70 nm in a thin film state while the compounds
according to Comparative Synthesis Examples 1 to 3 have FWHM's of
greater than or equal to about 75 nm in a thin film state.
[0175] Particularly, the compounds according to Synthesis Examples
1 to 9 show a ratio of less than 2.5 between FWHMs in a solution
state and in a thin film state, while the compounds according to
Comparative Synthesis Examples 1 to 3 show a ratio of greater than
2.5 between FWHMs in a solution state and in a thin film state.
From the results, the compounds according to Synthesis Examples 1
to 9 have higher green wavelength selectivity in a thin film state
compared with the compounds according to Comparative Synthesis
Examples 1 to 3.
Manufacture of Organic Photoelectronic Device
EXAMPLE 1
[0176] An about 100 nm-thick anode is formed by sputtering ITO on a
glass substrate, and then a 10 nm-thick charge auxiliary layer is
formed thereon by depositing a molybdenum oxide (MoO.sub.x,
0<x.ltoreq.3). Subsequently, an 85 nm-thick active layer is
formed on the molybdenum oxide thin film by codepositing the
compound (a p-type semiconductor compound) according to Synthesis
Example 1 and C.sub.60 (an n-type semiconductor compound) in a
thickness ratio of 1:1. Then, an 80 nm-thick cathode is formed on
the active layer by sputtering ITO, manufacturing an organic
photoelectronic device.
EXAMPLE 2
[0177] An organic photoelectronic device is manufactured according
to the same method as Example 1, except for using the compound
according to Synthesis Example 2 instead of the compound according
to Synthesis Example 1.
EXAMPLE 3
[0178] An organic photoelectronic device is manufactured according
to the same method as Example 1, except for using the compound
according to Synthesis Example 3 instead of the compound according
to Synthesis Example 1.
EXAMPLE 4
[0179] An organic photoelectronic device is manufactured according
to the same method as Example 1, except for using the compound
according to Synthesis Example 4 instead of the compound according
to Synthesis Example 1.
EXAMPLE 5
[0180] An organic photoelectronic device is manufactured according
to the same method as Example 1, except for using the compound
according to Synthesis Example 5 instead of the compound according
to Synthesis Example 1.
EXAMPLE 6
[0181] An organic photoelectronic device is manufactured according
to the same method as Example 1, except for using the compound
according to Synthesis Example 6 instead of the compound according
to Synthesis Example 1.
EXAMPLE 7
[0182] An organic photoelectronic device is manufactured according
to the same method as Example 1, except for using the compound
according to Synthesis Example 7 instead of the compound according
to Synthesis Example 1.
EXAMPLE 8
[0183] An organic photoelectronic device is manufactured according
to the same method as Example 1, except for using the compound
according to Synthesis Example 8 instead of the compound according
to Synthesis Example 1.
EXAMPLE 9
[0184] An organic photoelectronic device is manufactured according
to the same method as Example 1, except for using the compound
according to Synthesis Example 9 instead of the compound according
to Synthesis Example 1.
COMPARATIVE EXAMPLE 1
[0185] An organic photoelectronic device is manufactured according
to the same method as Example 1, except for using the compound
according to Comparative Synthesis Example 1 instead of the
compound according to Synthesis Example 1.
COMPARATIVE EXAMPLE 2
[0186] An organic photoelectronic device is manufactured according
to the same method as Example 1, except for using the compound
according to Comparative Synthesis Example 2 instead of the
compound according to Synthesis Example 1.
COMPARATIVE EXAMPLE 3
[0187] An organic photoelectronic device is manufactured according
to the same method as Example 1, except for using the compound
according to Comparative Synthesis Example 3 instead of the
compound according to Synthesis Example 1.
Evaluation II
[0188] Image sensors including the organic photoelectronic devices
according Examples 1 to 9 and Comparative Examples 1 to 3 are
designed to evaluate crosstalk of the image sensors.
[0189] The crosstalk evaluation is performed as follows.
[0190] Each compound according to according to Synthesis Example 1
to 9 and Comparative Synthesis Examples 1 to 3, and C.sub.60, in a
ratio of 1:1, are respectively formed as a layer, and n and k are
obtained by using spectroscopic ellipsometry. The n and k values
and photoelectronic conversion efficiency of a silicon photodiode
and an organic photoelectronic device are used to obtain spectrum
sensitivity of red, green, and blue elements having a structure
shown in FIGS. 3 and 4 by using an FDTD (finite difference time
domain). Herein, a wavelength region is divided into three regions
of 440-480 nm (blue), 520-560 nm (green), and 590-630 nm (red), and
how much the other two optical conversion elements interfere with
each particular region is evaluated. In other words, when an
integral of a sensitivity curve of a blue element in the 440-480 nm
is regarded as 100, a relative integral of sensitivity curves of
red and green elements in the 440-480 nm is obtained. This value is
crosstalk of the red and green elements regarding the blue region
in the 440-480 nm range. The same process is performed regarding
the 520-560 nm range and the 590-630 nm range to obtain each
crosstalk therein. Lastly, the 6 values are averaged to obtain all
crosstalk.
[0191] The results are provided in Table 2.
TABLE-US-00002 TABLE 2 Average crosstalk (%) Example 1 22.0 Example
2 27.8 Example 3 28.2 Example 4 27.8 Example 5 29.1 Example 6 27.4
Example 7 29.1 Example 8 21.2 Example 9 28.2 Comparative Example 1
35.7 Comparative Example 2 36.5 Comparative Example 3 33.2
[0192] In Table 2, the crosstalk in each pixel indicates a ratio of
unnecessarily inflowing light other than light of a particular
wavelength region into each pixel when light in the wavelength
regions of 590-630 nm, 520-560 nm, and 440-480 nm inflow 100% into
the red pixel (R), green pixel (G), and blue pixel (B), and the
average crosstalk may be defined as an average of a ratio of
unnecessarily inflowing light into the red pixel (R) other than
light of a red wavelength region, a ratio of unnecessarily
inflowing light into the green pixel (G) other than light of a
green wavelength region, and a ratio of unnecessarily inflowing
light into the blue pixel (B)) other than light of a blue
wavelength region.
[0193] Referring to Table 2, the image sensors including the
organic photoelectronic device according to Examples 1 to 9 show
remarkably decreased average crosstalk compared with the image
sensors including the organic photoelectronic devices according to
Comparative Examples 1 to 3. Specifically, the image sensors
including the organic photoelectronic devices according to Examples
1 to 9 show average crosstalk of less than or equal to about 30%,
while the image sensors including the organic photoelectronic
devices according to Comparative Examples 1 to 3 show average
crosstalk of greater than or equal to about 33%.
[0194] FIG. 9 is a graph showing a relationship between a FWHM and
crosstalk of the image sensors including the organic
photoelectronic devices according to Examples 1 to 9 and
Comparative Examples 1 to 3.
[0195] Referring to FIG. 9, the image sensors including the organic
photoelectronic devices according to Examples 1 to 9, that is,
using the compounds having a ratio of less than 2.5 between FWHMs
in a solution state and in a thin film state, show average
crosstalk of less than or equal to about 30%, while the image
sensors including the organic photoelectronic devices according to
Comparative Examples 1 to 3, that is, using the compounds having a
ratio of greater than about 2.5 between FWHMs in a solution state
and in a thin film state, show average crosstalk of greater than or
equal to about 33%. From the results, a relationship between a
ratio of FWHMs in a solution state and in a thin film state of the
compounds used in the active layer, and crosstalk of an image
sensor, may be confirmed.
[0196] Referring to the examples and comparative examples, when the
subphthalocyanine derivatives according to the examples are used as
a material for the organic photoelectronic conversion device, an
absorption spectrum difference between solution state and
vacuum-deposited thin film state is small (an FWHM ratio of less
than or equal to 2.5), and crosstalk of less than or equal to 30
may be realized, when a green organic photoelectronic conversion
film is stacked on a red and blue Si photoelectronic conversion
device in an image sensor, which is usefully used. On the contrary,
a material, for example, a conventional subphthalocyanine chloride,
has relatively large crosstalk, so color separation in an image
sensor is difficult and thus interference between pixels becomes
larger and performance may be degraded. Accordingly, when the
subphthalocyanine derivative having an FWHM ratio of less than or
equal to 2.5 is used for a green absorption photoelectronic
conversion device, a relatively high performance image sensor may
be realized.
[0197] While this disclosure has been described in connection with
what is presently considered to be practical example embodiments,
it is to be understood that the inventive concepts are not limited
to the disclosed embodiments, but, on the contrary, is intended to
cover various modifications and equivalent arrangements included
within the spirit and scope of the appended claims.
* * * * *