U.S. patent application number 10/114488 was filed with the patent office on 2003-10-02 for encapsulated organic semiconductor device and method.
This patent application is currently assigned to Motorola, Inc.. Invention is credited to Gamota, Daniel, Kalyanasundaram, Krishna, Scheifers, Steven, Skipor, Andrew.
Application Number | 20030183915 10/114488 |
Document ID | / |
Family ID | 28453789 |
Filed Date | 2003-10-02 |
United States Patent
Application |
20030183915 |
Kind Code |
A1 |
Scheifers, Steven ; et
al. |
October 2, 2003 |
Encapsulated organic semiconductor device and method
Abstract
A semiconductor device comprising organic semiconductor material
(14) has one or more barrier layers (16) disposed at least
partially thereabout to protect the organic semiconductor material
(14) from environment-driven changes that typically lead to
inoperability of a corresponding device. If desired, the barrier
layer can be comprised of partially permeable material that allows
some substances therethrough to thereby effect disabling of the
encapsulated organic semiconductor device after a substantially
predetermined period of time. Getterers (141) may also be used to
protect, at least for a period of time, such organic semiconductor
material.
Inventors: |
Scheifers, Steven; (Hoffman
Estates, IL) ; Gamota, Daniel; (Palatine, IL)
; Skipor, Andrew; (West Chicago, IL) ;
Kalyanasundaram, Krishna; (Chicago, IL) |
Correspondence
Address: |
FITCH EVEN TABIN AND FLANNERY
120 SOUTH LA SALLE STREET
SUITE 1600
CHICAGO
IL
60603-3406
US
|
Assignee: |
Motorola, Inc.
|
Family ID: |
28453789 |
Appl. No.: |
10/114488 |
Filed: |
April 2, 2002 |
Current U.S.
Class: |
257/682 ;
257/635; 257/642; 257/644; 438/143; 438/310; 438/471; 438/476 |
Current CPC
Class: |
H01L 51/524 20130101;
H01L 2924/0002 20130101; H01L 2924/00 20130101; H01L 2924/0002
20130101; H01L 51/5243 20130101; H01L 51/5259 20130101; H01L
51/5253 20130101; H01L 51/0516 20130101; H01L 51/107 20130101 |
Class at
Publication: |
257/682 ;
438/143; 438/310; 438/471; 438/476; 257/635; 257/642; 257/644 |
International
Class: |
H01L 023/552; H01L
023/26 |
Claims
We claim:
1. An apparatus comprising: an organic semiconductor device
containing at least some organic semiconductor material; an oxygen
barrier disposed between the organic semiconductor material and
local environment such that the organic semiconductor material is
substantially protected from significant electrical performance
degradation due to oxygen in the local environment.
2. The apparatus of claim 1 wherein the organic semiconductor
device further includes a substrate and wherein the at least some
organic semiconductor material is disposed overlying the
substrate.
3. The apparatus of claim 2 wherein the substrate comprises a
material that is substantially impermeable to oxygen.
4. The apparatus of claim 2 wherein the substrate comprises a
material that is permeable to oxygen.
5. The apparatus of claim 4 wherein the substrate has an oxygen
barrier disposed thereon such that the organic semiconductor
material is substantially protected from electrical performance
degradation due to oxygen in the local environment that would
otherwise permeate through the substrate.
6. The apparatus of claim 1 wherein the oxygen barrier is comprised
of an oxygen permeable carrier and an oxygen barrier material that
is disposed on the carrier.
7. The apparatus of claim 6 wherein the oxygen permeable carrier
comprises mylar and the oxygen barrier material comprises one of a
metal and silica.
8. The apparatus of claim 6 and further comprising an adhesive
material disposed between the oxygen barrier and the organic
semiconductor material.
9. The apparatus of claim 1 wherein the oxygen barrier is comprised
of silica.
10. The apparatus of claim 9 wherein the silica is disposed on an
oxygen permeable carrier layer.
11. The apparatus of claim 1 and further comprising an H.sub.2O
barrier disposed between the organic semiconductor material and
local environment such that the organic semiconductor material is
substantially protected from significant electrical performance
degradation due to H.sub.2O.
12. The apparatus of claim 11 wherein the H.sub.2O barrier is a
barrier to both condensed and gaseous phase H.sub.2O.
13. The apparatus of claim 1 and further comprising a barrier that
is opaque with respect to at least one wavelength of light energy
and that is disposed between the organic semiconductor material and
external light sources such that the organic semiconductor material
is substantially protected from significant electrical performance
degradation due to the at least one wavelength of light energy from
external light sources.
14. A method comprising: providing at least one organic
semiconductor device having at least some organic semiconductor
material; disposing an oxygen barrier between the organic
semiconductor material and local environment such that the organic
semiconductor material is substantially protected from significant
electrical performance degradation due to oxygen in the local
environment.
15. The method of claim 14 wherein disposing an oxygen barrier
includes disposing a film comprising a gas permeable carrier and an
oxygen non-permeable layer.
16. The method of claim 14 wherein disposing an oxygen barrier
includes disposing silica over the organic semiconductor
material.
17. The method of claim 14 wherein disposing an oxygen barrier
includes disposing a first layer comprising a gas barrier over the
organic semiconductor material and a second layer comprising a
condensed water barrier over the first layer.
18. The method of claim the 17 wherein disposing a first layer
comprising a gas barrier over the organic semiconductor material
and a second layer comprising a condensed water barrier over the
first layer includes disposing an adhesive between the first layer
and the organic semiconductor material.
19. The method of claim 14 wherein disposing an oxygen barrier
includes disposing a first layer comprising a condensed water
barrier over the organic semiconductor material and a second layer
comprising a gas barrier over the first layer.
20. The method of claim 14 wherein providing at least one organic
semiconductor device comprises providing at least a first and
second organic semiconductor device and wherein disposing an oxygen
barrier includes disposing a first oxygen barrier over at least a
part of the first organic semiconductor device and disposing a
second oxygen barrier over at least a part of the second organic
semiconductor device, wherein the first and second oxygen barriers
are different from one another.
21. The method of claim 20 wherein the first oxygen barrier is less
impermeable to oxygen than the second oxygen barrier.
22. The method of claim 14 wherein disposing an oxygen barrier
includes disposing an oxygen barrier between the organic
semiconductor material and local environment such that the organic
semiconductor material is substantially protected for a
predetermined period of time from electrical performance
degradation due to oxygen in the local environment.
23. The method of claim 22 wherein the predetermined period of time
is less than 90 days.
24. An organic semiconductor assembly comprising: a substrate; at
least one device comprising organic semiconductor material disposed
on the substrate; environmental barrier means disposed over the
organic semiconductor material for substantially preventing, for at
least a predetermined period of time, oxygen in a surrounding
environment from contacting the organic semiconductor material and
causing significant electrical performance degradation of the
device.
25. The organic semiconductor assembly of claim 24 and further
comprising a plurality of devices comprised of organic
semiconductor material and being disposed on the substrate, wherein
the environmental barrier means are disposed over the plurality of
devices.
26. The organic semiconductor assembly of claim 24 wherein the
environmental barrier means includes a material that is
substantially impermeable to oxygen.
27. The organic semiconductor assembly of claim 26 wherein the
material that is substantially impermeable to oxygen has small
openings intentionally disposed therethrough which openings are
permeable to oxygen.
28. The organic semiconductor assembly of claim 24 wherein the
environmental barrier means are effective for only a predetermined
period of time to substantially prevent oxygen in a surrounding
environment from contacting the organic semiconductor material and
causing significant electrical performance degradation of the
device.
29. The organic semiconductor assembly of claim 24 wherein at least
one device comprised of the organic semiconductor material as
disposed on the substrate does not have the environmental barrier
means disposed thereover.
30. An apparatus comprising: an organic semiconductor device
containing at least some organic semiconductor material; a getterer
disposed between the organic semiconductor material and an external
environment such that the organic semiconductor material is
substantially protected from significant electrical performance
degradation due to at least some contents of the external
environment for at least some period of time.
31. The apparatus of claim 30 wherein the getterer comprises an
H.sub.2O desiccant.
32. The apparatus of claim 30 wherein the getterer comprises an
oxygen scavenger.
33. An apparatus comprising: an organic semiconductor device
containing at least some organic semiconductor material; an H2O
vapor barrier disposed between the organic semiconductor material
and local environment such that the organic semiconductor material
is substantially protected from significant electrical performance
degradation due to H2O vapor in the local environment.
34. A method comprising: providing at least one organic
semiconductor device having at least some organic semiconductor
material, which organic semiconductor material is sensitive to at
least one wavelength of light energy; disposing a barrier that is
partially, but not wholly, opaque to the at least one wavelength of
light energy between the organic semiconductor material and local
environment such that the organic semiconductor material is
substantially protected from significant electrical performance
degradation due to the at least one wavelength of light energy for
a period of time, but wherein the organic semiconductor material
will eventually degrade due to the at least one wavelength of light
energy.
Description
TECHNICAL FIELD
[0001] This invention relates generally to semiconductors and more
particularly to organic semiconductor materials.
BACKGROUND
[0002] Components and circuits comprised of semiconductor materials
are known in the art. Such technology has been highly successful.
For some applications, however, traditional semiconductor
processing over-performs and represents unneeded form factors and
capabilities at a commensurate additional cost. Traditional
semiconductor processing also usually requires batch processing to
achieve a reasonable cost per part because the fabrication
facilities and equipment required are extremely expensive. Also,
many semiconductor devices require a lengthy fabrication time and
often require numerous chemicals, some of which are highly toxic
and require special handling. These aspects of traditional
semiconductor fabrication do not well support low data storage and
data transmission rate applications and/or other less expensive
needs.
[0003] Organic semiconductors have been proposed as an alternative
to standard semiconductor paradigms. Organic semiconductors hold
the potential for serial or continuous processing and/or otherwise
relatively low cost manufacturing requirements. Unfortunately, to
date, while working organic semiconductor devices have been
demonstrated, the operating life of such devices tends towards
extreme brevity. In some instances, failure occurs within an hour
or two of fabrication. This results in many cases through
interaction of the organic semiconductor material with active
contaminants in the environment, including, for example, oxygen and
water (H.sub.2O in both condensed and vaporous form). Such
interaction eventually renders the organic material more conductive
than semiconductive and this usually leads to device failure.
[0004] Present industry efforts emphasize searching for an organic
semiconductor material that will withstand such environmental
conditions. These efforts do not guarantee success, however, and,
at a minimum, represent considerable expense and delay of
commercialization of the technology.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] The above needs are at least partially met through provision
of the encapsulated organic semiconductor device and method
described in the following detailed description, particularly when
studied in conjunction with the drawings, wherein:
[0006] FIG. 1 illustrates a first embodiment configured in
accordance with the invention;
[0007] FIG. 2 illustrates a detailed depiction of an oxygen barrier
embodiment configured in accordance with the invention;
[0008] FIG. 3 illustrates a detailed depiction of another oxygen
barrier embodiment configured in accordance with the invention;
[0009] FIG. 4 illustrates a detailed depiction of a multi-substance
barrier embodiment configured in accordance with the invention;
[0010] FIG. 5 illustrates a detailed depiction of an adhesion layer
used in conjunction with a barrier embodiment configured in
accordance with the invention;
[0011] FIG. 6 illustrates yet another depiction of an embodiment
configured in accordance with the invention;
[0012] FIG. 7 illustrates a multi-layer barrier embodiment
configured in accordance with the invention;
[0013] FIG. 8 illustrates a multi-device embodiment configured in
accordance with the invention;
[0014] FIG. 9 illustrates another multi-device embodiment
configured in accordance with the invention;
[0015] FIG. 10 illustrates another barrier embodiment configured in
accordance with the invention;
[0016] FIG. 11 illustrates yet another barrier embodiment
configured in accordance with the invention;
[0017] FIG. 12 illustrates a graph that depicts a movement from a
state of operability to a state of inoperability over time in
accordance with an embodiment of the invention;
[0018] FIG. 13 illustrates yet another multi-device embodiment
configured in accordance with the invention;
[0019] FIG. 14 illustrates a getterer layer embodiment configured
in accordance with the invention;
[0020] FIG. 15 illustrates a getterer layer embodiment configured
in accordance with the invention; and
[0021] FIG. 16 illustrates yet another getterer layer embodiment
configured in accordance with the invention.
[0022] Skilled artisans will appreciate that elements in the
figures are illustrated for simplicity and clarity and have not
necessarily been drawn to scale. For example, the dimensions of
some of the elements in the figures may be exaggerated relative to
other elements to help to improve understanding of various
embodiments of the present invention.
DETAILED DESCRIPTION
[0023] Generally speaking, pursuant to these various embodiments,
an organic semiconductor device or array of devices is at least
partially encapsulated by one or more barrier layers of material
that are substantially impermeable to one or more environmental
substances that would otherwise tend to effect significant
electrical performance degradation of the organic semiconductor
material itself. In one embodiment, one or more of the layers can
be purposefully partially permeable to allow for eventual failure
of the corresponding device after a substantially predetermined
period of time. In one embodiment, getterer material is used to
protect, at least for a time, organic semiconductor material from
the substance(s) being absorbed by the getterer.
[0024] Referring now to FIG. 1, a first embodiment will be
described. An initial substrate 10 can be comprised of a variety of
materials, including flexible and substantially rigid materials. In
general, the substrate 10 itself should be an insulator. Various
plastics, including thin flexible sheets such as polyester,
generally work well for these purposes. Depending upon the
application, however, other materials can work as well, including
treated cloth and paper. The substrate 10 can be of various sizes
as commensurate with the desired size of the final result.
[0025] An organic semiconductor device (or devices) is formed on
the substrate 10. For purposes of this description, the device is a
MOSFET (metal oxide semiconductor field effect transistor)
comprised of a gate electrode 11 having a dielectric layer 15
disposed thereover and a source electrode 12 and drain electrode 13
formed on the substrate 10. These electrodes are formed of a
conductive material with the gate, source and drain electrodes 11,
12 and 13 being formed of a material, such as copper, gold, silver,
nickel, platinum, conductive polymer thick film, conductive
polymer, carbon-based material, or tungsten as will result in an
ohmic contact as between itself and an organic semiconductor
material. An organic semiconductor material 14 overlies at least
portions of the source electrode 12 and drain electrode 13.
(Conductive paths to each electrode 11, 12, and 13 will ordinarily
be provided to facilitate desired functionality though for purposes
of clarity, such paths are not depicted in these figures.)
[0026] Any of the above elements (the electrodes 11, 12, and 13,
the dielectric 15, and the organic semiconductor material 14) can
be formed by use of one or more printing processes. For example,
contact printing processes (including but not limited to stamping,
screen printing, flexographic, and micro-contact printing) and
non-contact printing processes (including but not limited to ink
jet, electrostatic, laser transfer, and micro-dispensing) can be
used to print the indicated materials as described. Depending upon
the material form and carrier used, air drying and/or curing steps
may be appropriate to ensure the desired adhesion, electrical
performance, and mechanical integrity.
[0027] A typical device will have an overall thickness of only a
few microns (depending upon the specific materials, deposition
process, and number of layers) and can have a footprint ranging
from a few microns to one thousand or more microns. Notwithstanding
such sizes, when formed upon a flexible substrate, the result
device can maintain normal functionality even when flexed during
use (of course, extreme bending of the substrate may, at some
point, disrupt the continuity of one of more of the constituent
elements of the device).
[0028] In this embodiment, an oxygen barrier 16 is disposed over
the organic semiconductor material 14 to thereby protect the
organic semiconductor material 14, at least for a time, from
significant electrical performance degradation due to oxygen 17 in
the local environment. As shown, the barrier 16 completely covers
the organic semiconductor material 14. If desired, however, only
part of the organic semiconductor material 14 could be covered
though less protection will likely result. With reference to FIG.
2, the barrier 16 may be any material that is substantially
impermeable to oxygen. In one embodiment, silica is disposed to
thereby comprise the barrier layer 16. For example, methods as
known in the art such as vacuum deposition, solution processing,
and so forth could be used to deposit the silica or other barrier
material. With reference to FIG. 3, in another embodiment, the
barrier 16 can be a free standing film comprised of an oxygen
permeable carrier 31 and an oxygen barrier material 32, such as
silica, that is disposed on the carrier 31. For example, mylar with
an aluminum coating could be used in this regard. Such a carrier 31
can be flexible if desired and applied to the organic semiconductor
material 14 using lamination or other application technique as
appropriate to the application. Of course, and referring now to
FIG. 4, it is also possible for the oxygen barrier 16 to also serve
as a barrier to other potentially damaging substances. For example,
as depicted, the barrier 16 can substantially repel both oxygen and
H.sub.2O (in vapor and/or condensed form). Some suitable materials
may be applied directed to the organic semiconductor material 14
and will adhere satisfactorily thereto (either with or without
subsequent treatment and/or curing as appropriate to the material
used). In other instances it may be appropriate to apply the
barrier layer 16 to the organic semiconductor material 14 using an
intervening adhesive material 51 as shown in FIG. 5.
[0029] In each of the above described embodiments, oxygen in the
local environment is substantially prevented from reaching the
organic semiconductor material 14 through use of a barrier layer 16
disposed over the organic semiconductor material 14. In embodiments
where the substrate 10 layer itself comprises an oxygen impermeable
material, such a configuration should contribute to significantly
improved operative life of the corresponding organic semiconductor
active device(s). When the substrate 10 is not itself impermeable
to oxygen, however, then as depicted in FIG. 6 an additional
barrier layer 61 as applied to the substrate 10 will serve to
protect the organic semiconductor material 14 from harm due to
oxygen passing through the substrate 10. As depicted, this
additional barrier layer 61 is disposed on a side of the substrate
10 that is common to the organic semiconductor device itself. In an
appropriate configuration, however, it may also be possible and or
suitable to dispose the additional barrier layer on the opposing
side of the substrate 10 or to dispose the additional barrier layer
on both sides of the substrate 10.
[0030] As noted above, oxygen is not the only environmental
substance that can contribute to a greatly reduced operating life
for an organic semiconductor device. H.sub.2O (in vapor and/or
condensed form) is another common substance that can detrimentally
impact operating life expectances. When the oxygen barrier 16
constitutes a barrier to H.sub.2O (in vapor and/or condensed form)
as described above with respect to FIG. 4, then the barrier 16 will
serve to also protect the organic semiconductor material 14 from
this substance. When the oxygen barrier 16 does not also constitute
an H.sub.2O barrier, however, then if desired, an additional
H.sub.2O barrier layer 71 can be applied as depicted in FIG. 7 to
additionally protect the organic semiconductor material 14 from
H.sub.2O (in vapor and/or condensed form). As shown, the H.sub.2O
barrier 71 can overly the oxygen barrier 16. If desired, of course,
this layering order can be reversed. It should also be noted that
substances such as condensed H.sub.2O themselves constitute a good
solvent and hence often contain yet additional contaminants such
as, for example, carbonic acid or free ions. Such contaminants can
degrade performance of organic semiconductor materials and hence in
many instances it will be appropriate or necessary for the H.sub.2O
barrier to also be relatively impermeable to such substances that
are dissolved in the H.sub.2O and/or for an additional barrier
layer to be used that is impermeable to such substances.
[0031] Oxygen and H.sub.2O (in vapor and/or condensed form)
barriers have been used above to illustrate the described
embodiments. Other barriers are of course available and can be used
in substitution for or in combination with the barriers described
to protect the organic semiconductor material 14 against a variety
of performance-degrading environmental agents as appropriate to a
given set of operating circumstances.
[0032] A plurality of organic semiconductor devices can be formed
on a single substrate. If desired, and as depicted in FIG. 8, each
such organic semiconductor device sharing a substrate can be
protected by a common barrier layer 16. Such an embodiment can be
used regardless of whether the devices themselves are
interconnected or constitute discrete circuits or components. Or,
if desired, some such devices can be protected by a barrier layer
16 and others can be left unprotected as illustrated in FIG. 9.
[0033] As noted earlier, the purpose of the barrier layer (or
layers) is to protect the organic semiconductor material from
significantly changing in response to environmental constituents.
This tendency of organic semiconductor devices to fail after
sufficient exposure to such influences, however, may under some
circumstances be an exploitable tendency. For example, it may be
desirable to limit the useful life of a given circuit or component
to a particular time frame (one very simple example would be to use
a time-limited circuit to indicate, by its operable status, passage
of a predetermined period of time). With such designs in mind, a
barrier layer 101 can be comprised, for example, of material that,
while somewhat resistant to the passage of oxygen (or other
substance of concern or interest) is nevertheless somewhat
permeable to oxygen as illustrated in FIG. 10. As another approach,
and as illustrated in FIG. 11, a material 111 that is otherwise
substantially impermeable to oxygen (or other substance of concern
or interest) can be deposited with small openings 112 disposed
therethrough to allow a desired amount of oxygen to pass
therethrough (such small openings 112 can be the result of the
deposition process itself and/or can be subsequently formed through
use of, for example, lasers, mechanical drills, and so forth). By
using such a barrier layer, a sufficient amount of oxygen (or other
substance of concern or interest) will eventually pass through the
barrier layer and cause a corresponding failure of the encapsulated
device as generally illustrated in FIG. 12. For example, a
particular circuit could be fashioned that, after approximately 90
days, would likely fail due to impairment of the circuit's organic
semiconductor material due to this cause. Such circuits, having a
substantially controllable lifespan, could be used for a variety of
purposes. The relatively low cost of such a circuit makes more
reasonable the notion of fielding an intentionally fixed-duration
circuit.
[0034] As described, the entire device is encapsulated within a
partially permeable barrier layer. If desired, when a plurality of
devices are present on a single substrate 10 as shown in FIG. 13,
some of the devices can be encapsulated within a fully impermeable
barrier layer 16 as described earlier while at least one of the
remaining devices is encapsulated instead by a partially permeable
barrier layer 131. Again, the purpose of such a configuration would
be to provide a limited life circuit or circuit element that would
likely fail after a reasonably predictable period of time. This
failure mode could be detected by the remaining operable circuitry
to effect a variety of responses as appropriate to a given
application.
[0035] The embodiments discussed above provide an impermeable, or
partially permeable, barrier to one or more environmental
components. Another kind of substance is known as a getterer. As
illustrated in FIG. 14, a getterer 141 will absorb rather than bar
or pass a corresponding substance. Various getterers are known in
the art and include H.sub.2O getterers (desiccants of various
kinds) and oxygen getterers (so-called oxygen scavengers such as
oxygen scavenging polyamides). Such a getterer 141 can be used as a
layer around an organic semiconductor device as depicted in FIG.
15. So configured, the getterer 141 will absorb the corresponding
environmental substance and protect the organic semiconductor
material 14 until the getterer 141 becomes saturated. Once
saturated, the getterer 141 will typically begin to release the
previously absorbed substance. When this occurs the organic
semiconductor material 14 will then react accordingly and the
corresponding device will likely fail. So, again, a limited-life
device can be enabled with the life expectancy being determined at
least in part by the amount of absorbent material provided. If
desired, and as illustrated in FIG. 16, a barrier layer 161 can be
disposed over the exterior of the getterer 141 to provide
additional protection. If the barrier layer 161 is of the type that
allows some egress to the controlled substance, as depicted, then
this attribute again becomes a parameter that can be utilized to
achieve a device having a particular likely operative lifespan.
[0036] The various embodiments described above provide different
ways to fully or partially protect an organic semiconductor device
(or devices) from a variety of substances. Some organic
semiconductor materials, however, may be sensitive to one or more
bandwidths of light energy (including, in particular, violet and
ultraviolet bands). Such materials may degrade when exposed to the
corresponding light and such degradation may again lead to
electronic failure of the device. The substance barrier or barriers
(or getterers) described above may therefore also be fully or
partially opaque to specific wavelengths of light energy to avoid
or control performance degradation due to this contributing factor.
Such light barriers can either be single-function in this regard or
the desired opacity can be achieved with a dual-purpose barrier
that also serves, for example, to block oxygen. A partially opaque
light barrier may be used when seeking to provide a limited life
device wherein the approximate lifespan of the device is at least
partially controllable by appropriate selection of the barrier
opacity.
[0037] The various embodiments described above provide different
ways to fully or partially protect an organic semiconductor device
(or devices) over a substantially determinable period of time
(widely varying substance concentrations in the ambient environment
will of course likely tend to lead to variability in the lifetime
estimation as well). Fully or partially impermeable materials
and/or getterers can be utilized to effect these embodiments. The
various embodiments set forth are relatively inexpensive and do not
add undue expense to detract from the already relatively low costs
of working with organic semiconductor materials. These techniques
are also workable with a variety of substrate materials.
Furthermore, these embodiments are ready for immediate deployment
and need not await future significant developments with respect to
organic semiconductor materials themselves.
[0038] The embodiments described above present the various elements
as being stacked in a particular order. Other orientations,
however, are possible and acceptable (especially with respect to
the device elements themselves). Furthermore, and as stated
earlier, the MOSFET device has been used as an illustrative
mechanism only. These embodiments are usable with virtually all
other organic semiconductor device configurations as well.
[0039] A wide variety of materials can be used consistently with
the above processes and embodiments. Furthermore, a wide range of
processing parameters can be varied, including device size and
constituent element sizes, to suit a wide variety of application
requirements. Those skilled in the art will recognize that a wide
variety of modifications, alterations, and combinations can be made
with respect to the above described embodiments without departing
from the spirit and scope of the invention, and that such
modifications, alterations, and combinations are to be viewed as
being within the ambit of the inventive concept.
* * * * *