U.S. patent application number 15/723382 was filed with the patent office on 2018-08-16 for light-emitting device and manufacturing method of light-emitting device.
The applicant listed for this patent is TYNTEK CORPORATION. Invention is credited to YI-HUNG CHEN, YUNG-JUNG LIANG.
Application Number | 20180233642 15/723382 |
Document ID | / |
Family ID | 63078901 |
Filed Date | 2018-08-16 |
United States Patent
Application |
20180233642 |
Kind Code |
A1 |
CHEN; YI-HUNG ; et
al. |
August 16, 2018 |
LIGHT-EMITTING DEVICE AND MANUFACTURING METHOD OF LIGHT-EMITTING
DEVICE
Abstract
The light-emitting device includes a base plate, a bonding metal
layer, a conductive oxide layer, an epitaxial layer, an insulation
layer, a first ohmic contact layer, a second ohmic contact layer, a
third ohmic contact layer, and a conductor line. The light-emitting
device of the present invention uses the process of providing a
conductor line to connect an ohmic contact layer, instead of wire
bonding, so that a package process required by wire bonding can be
eliminated to thereby reduce the size of the light-emitting device.
Further, the light-emitting device, after the formation of the
conductor line on the ohmic contact layer, allows for performance
of a step of directly bonding to a circuit board so as to reduce
the package size and simplify equipment necessary for the package
process to thereby further lower down fabrication costs, achieving
the effects of simplification of operation and fast
fabrication.
Inventors: |
CHEN; YI-HUNG; (MIAOLI
COUNTY, TW) ; LIANG; YUNG-JUNG; (MIAOLI COUNTY,
TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TYNTEK CORPORATION |
Hsinchu City |
|
TW |
|
|
Family ID: |
63078901 |
Appl. No.: |
15/723382 |
Filed: |
October 3, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01L 33/382 20130101;
H01L 2933/0016 20130101; H01L 33/62 20130101; H01L 2933/0066
20130101; H01L 33/44 20130101; H01L 33/36 20130101; H01L 33/0093
20200501; H01L 33/42 20130101 |
International
Class: |
H01L 33/62 20060101
H01L033/62; H01L 33/44 20060101 H01L033/44; H01L 33/36 20060101
H01L033/36 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 13, 2017 |
TW |
106104559 |
Claims
1. A manufacturing method of a light-emitting device, comprising
providing a first base plate; forming an epitaxial layer on the
first base plate; forming a conductive oxide layer on the epitaxial
layer; forming a first bonding metal layer on the conductive oxide
layer; providing a second base plate; forming a second bonding
metal layer on the second base plate; bonding the first bonding
metal layer and the second bonding metal layer to each other;
removing the first base plate; removing a portion of the epitaxial
layer; removing a portion of the first bonding metal layer, the
second bonding metal layer, and the conductive oxide layer; forming
an insulation layer to cover the second base plate, the first
bonding metal layer, the second bonding metal layer, the conductive
oxide layer, and the epitaxial layer; removing portions of the
insulation layer on the second base plate, the conductive oxide
layer, and the epitaxial layer to expose, partly, a surface of the
second base plate, a surface of the conductive oxide layer, and a
surface of the epitaxial layer; forming a first ohmic contact layer
on the surface of the second base plate; forming a second ohmic
contact layer on the surface of the epitaxial layer; forming a
third ohmic contact layer on the surface of the conductive oxide
layer; and forming a conductor line to connect the first ohmic
contact layer and the second ohmic contact layer to each other
2. The manufacturing method of the light-emitting device as claimed
in claim 1 further comprising a step of reducing a thickness of the
second base plate.
3. The manufacturing method of the light-emitting device as claimed
in claim 2 further comprising a step of bonding the light-emitting
device to a circuit board through an adhering technique.
4. The manufacturing method of the light-emitting device as claimed
in claim 2, wherein the light-emitting device has a thickness
between 80 and 350 micrometers.
5. The manufacturing method of the light-emitting device as claimed
in claim 3, wherein the adhering technique comprises surface
mounting technology.
6. The manufacturing method of the light-emitting device as claimed
in claim 1, wherein the step of removing a portion of the epitaxial
layer comprises removing parts of the epitaxial layer on a first
side edge and a second side edge to expose a portion of the
conductive oxide layer.
7. The manufacturing method of the light-emitting device as claimed
in claim 6, wherein the step of removing a portion of the first
bonding metal layer, the second bonding metal layer, and the
conductive oxide layer comprises removing a part of the first
bonding metal layer, the second bonding metal layer, and the
conductive oxide layer on the first side edge.
8. The manufacturing method of the light-emitting device as claimed
in claim 1, wherein the second base plate comprises a
non-conductive plate.
9. The manufacturing method of the light-emitting device as claimed
in claim 1, wherein the second base plate comprises a
light-transmitting plate or a non-light-transmitting plate.
10. A light-emitting device, comprising a base plate; a bonding
metal layer, which is disposed on a surface of a first part of the
base plate; a conductive oxide layer, which is disposed on the
bonding metal layer; an epitaxial layer, which is disposed on a
surface of a first part. of the conductive oxide layer; an
insulation layer, which is disposed on a first side edge of the
bonding metal layer, the conductive oxide layer, and the epitaxial
layer and is disposed a surface of a first part of the epitaxial
layer; a first ohmic contact layer, which is disposed on a surface
of a second part of the base plate; a second ohmic contact layer,
which is disposed on a surface of a second part of the epitaxial
layer; a third ohmic contact layer, which is disposed on a surface
of a second part of the conductive oxide layer; and a conductor
line, which electrically connects the first ohmic contact layer and
the second ohmic contact layer to each other.
11. The light-emitting device as claimed in claim 10, wherein the
insulation layer comprises silicon dioxide or silicon nitride.
12. The light-emitting device as claimed in claim 10, wherein the
insulation layer is further disposed on a surface of a third part
of the epitaxial layer and arranged between a second side edge of
the epitaxial layer and the third ohmic contact layer.
13. The light-emitting device as claimed in claim 10, wherein the
conductor line has a width that is smaller than a diameter of a
solder ball.
14. The light-emitting device as claimed in claim 10 further
comprising a circuit board electrically connected with the second
ohmic contact layer and the third ohmic contact layer.
15. The light-emitting device as claimed in claim 14, wherein the
circuit board is electrically connected, through silver glue or
solder paste, with the conductor line and the third ohmic contact
layer.
16. The light-emitting device as claimed in claim 10, wherein the
light-emitting device has a thickness between 80 and 350
micrometers.
17. The light-emitting device as claimed in claim 10, wherein the
base plate comprises a non-conductive plate.
18. The light-emitting device as claimed in claim 17, wherein the
non-conductive plate comprises a ceramic plate, an aluminum nitride
plate, or an aluminum oxide plate.
19. The light-emitting device as claimed in claim 10, wherein the
base plate comprises a light-transmitting plate or a
non-light-transmitting plate.
20. The light-emitting device as claimed in. Claim 10 further
comprising a non-conductive oxide layer disposed between the
epitaxial layer and the conductive oxide layer.
21. The light-emitting device as claimed in claim 20, wherein the
non-conductive oxide layer comprises at least one via connected
with the epitaxial layer and the conductive oxide layer.
22. The light-emitting device as claimed in claim 21, wherein the
via is a metallic material.
23. The light-emitting device as claimed in claim 22, wherein the
metallic material comprises zinc gold, beryllium gold, chromium, or
gold.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a light-emitting device and
a manufacturing method of a light-emitting device, and in
particular to a light-emitting device and a manufacturing method of
a light-emitting device that involves chip scale package through a
design of wiring and a packaging process corresponding thereto.
BACKGROUND OF THE INVENTION
[0002] In the technical field of light-emitting devices,
light-emitting diodes are a widely used product and they are
applicable to various technical fields, particularly applications
concerning thinned and small-sized products being increasingly
widened, so that an increasing number of products are being under
development toward "chip scale package". For example, a number of
products that involve the use of light-emitting diodes are made
with chip scale package by taking flip chip package for size
reduction and thinning.
[0003] Referring to FIG. 1A, a schematic view is given to
illustrate a structure of a known light-emitting diode. The known
light-emitting diode 1 comprises a transparent base plate 11,
epitaxial layers 12,13, an insulation layer 14, and electrodes 15,
16. In FIG. 1A, the electrodes 15, 16 are of horizontal electrode
structures, and in a manufacturing process, a metal ball 17 is
placed on the electrode 16 to make the electrodes 15, 16 identical
in height. However, such a process of placing the metal ball 17 on
the electrode 16 often results in a height difference between the
electrodes 15 and 16 and this increases the product defect rate,
and also increases potential risk and cost of fabrication.
[0004] Referring to FIG. 1B, an improvement over the structure of
the light-emitting diode shown in FIG. 1A is provided. To overcome
the issue of height difference between the electrodes 15, 16 due to
the arrangement of the metal ball shown in FIG. 1A, FIG. 1B
provides a structure of a light-emitting diode 1, in which a recess
is formed with the insulation layer 14 and the electrode 16 is
disposed in the recess in order to make the electrodes 15, 16
identical to each other in height. However, such a process requires
an additional operation of forming the recess, and, in addition,
since a base plate 11 used in flip chip packaging and the flip chip
process of FIG. 1A both need a transparent base plate 11, alignment
of the electrodes 15, 16 in making a package is difficult.
[0005] Further, if the techniques that involve flip chip packaging
to achieve size reduction and thinning takes an eutectic process to
form the structure of the light-emitting diode, then the equipment
used for eutectic process requires a higher standard and thus, the
fabrication cost may be increased.
[0006] Thus, it is an important contemporary technical issue to
provide a process that makes a package that is closer to a chip
size.
SUMMARY OF THE INVENTION
[0007] In view of the above, the present invention discloses a
light-emitting device, which comprises a base plate, the bonding
metal layer, the conductive oxide layer, the epitaxial layer, the
insulation layer, the first ohmic contact layer, the second ohmic
contact layer, the third ohmic contact layer and the conductor
line. The bonding metal layer is disposed on a surface of a first
part of the base plate. The conductive oxide layer is disposed on
the bonding metal layer. The epitaxial layer is disposed on a
surface of a first part of the conductive oxide layer. The
insulation layer is disposed on a first side edge of the bonding
metal layer, the conductive oxide layer, and the epitaxial layer
and disposed on a surface of a first part of the epitaxial layer.
The first ohmic contact layer is disposed on a surface of a second
part of the base plate. The second ohmic contact layer is disposed
on a surface of a second part of the epitaxial layer. The third
ohmic contact layer is disposed on a surface of a second part of
the conductive oxide layer. The conductor line electrically
connects the first ohmic contact layer and the second ohmic contact
layer to each other.
[0008] The present invention also discloses a manufacturing method
of a light-emitting device, which comprises the following step:
providing a first base plate; forming an epitaxial layer on the
first base plate; forming a conductive oxide layer on the epitaxial
layer; forming a first bonding metal layer on the conductive oxide
layer; providing a second base plate; forming a second bonding
metal layer on the second base plate; bonding the first bonding
metal layer and the second bonding metal layer to each other;
removing the first base plate; removing a portion of the epitaxial
layer; removing a portion of the first bonding metal layer, the
second bonding metal layer, and the conductive oxide layer; forming
an insulation layer to cover the second base plate, the first
bonding metal layer, the second bonding metal layer, the conductive
oxide layer, and the epitaxial layer; removing portions of the
insulation layer on the second base plate, the conductive oxide
layer, and the epitaxial layer to expose, partly, a surface of the
second base plate, a surface of the conductive oxide layer, and a
surface of the epitaxial layer; forming a first ohmic contact layer
on the surface of the second base plate; forming a second ohmic
contact layer on the surface of the epitaxial layer; forming a
third ohmic contact layer on the surface of the conductive oxide
layer; and forming a conductor line to connect the first ohmic
contact layer and the second ohmic contact layer to each other.
[0009] Based on the above, compared to the prior art, where a metal
ball is disposed on an electrode and a recess is provided for the
purposes of making the electrodes identical, in height, to each
other, the present invention involves a process of providing a
conductor line to more precisely control the height of electrode so
as to prevent an issue associated with height difference of
electrodes. Further, the light-emitting device of the present
invention uses the process of providing a conductor line to connect
an ohmic contact layer, instead of wire bonding, so that a package
process required by wire bonding can be eliminated to thereby
reduce the size of the light-emitting device. Further, the
light-emitting device of the present invention, after the formation
of the conductor line on the ohmic contact layer, allows for
performance of a step of directly bonding to a circuit board so as
to reduce the package size and simplify equipment necessary for the
package process to thereby further lower down fabrication costs,
achieving the effects of simplification of operation and fast
fabrication, allowing for wide application to the technical field
of chip size package.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The present invention will be apparent to those skilled in
the art by reading the following description of preferred
embodiments thereof with reference to the drawings, in which:
[0011] FIG. 1A is a schematic view showing a structure of a known
light-emitting diode;
[0012] FIG. 1B is a schematic view illustrating an improvement of
the structure of the light-emitting diode shown in FIG. 1A;
[0013] FIG. 2 is a flow chart illustrating a manufacturing method
of a light-emitting device according to the present invention;
[0014] FIGS. 3A-3H are schematic views illustrating different steps
of the manufacturing method of the light-emitting device according
to the present invention;
[0015] FIG. 4 is a schematic view showing a structure of a
light-emitting device according to the present invention; and
[0016] FIG. 5 is a schematic view illustrating a structure of
another light-emitting device according to the present
invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] Referring to FIGS. 2 and 3A-3H, which respectively provide a
flow chart illustrating a manufacturing method of a light-emitting
device according to the present invention and different steps of
the manufacturing method, the manufacturing method of a
light-emitting device 3 generally comprises the following steps: in
Step S2, a first base plate 31 is provided. In Step S4, an
epitaxial layer 32 is formed. on the first base plate 31. In Step
S6, a conductive oxide layer 33 is formed on the epitaxial layer
32. In Step S8, a first bonding metal layer 34 is formed on the
conductive oxide layer 33. In Step S10, a second base plate 35 is
provided. In Step S12, a second bonding metal layer 36 is formed on
the second base plate 35. In Step S14, the first bonding metal
layer 34 and the second bonding metal layer 36 are bonded to each
other. In Step S16, the first base plate 31 is removed. In Step
S18, a portion of the epitaxial layer 32 is removed. In Step S20, a
portion of the first bonding metal layer 34, the second bonding
metal layer 36, and the conductive oxide layer 33 is removed. In
Step S22, an insulation layer 37 is formed to cover the second base
plate 35, the first bonding metal layer 34, the second bonding
metal layer 36, the conductive oxide layer 33, and the epitaxial
layer 32. In Step S24, portions of the insulation layer 37 that are
located on the second base plate 35, the conductive oxide layer 33,
and the epitaxial layer 32 are removed to expose a portion of a
surface of the second base plate 35, a portion of a surface of the
conductive oxide layer 33, and a portion of a surface of the
epitaxial layer 32. In Step S26, a first ohmic contact layer E1 is
formed on the surface of the second base plate 35 and a second
ohmic contact layer E2 is formed on the surface of the epitaxial
layer 32. In Step S28, a third ohmic contact layer E3 is formed on
the surface of the conductive oxide layer 33. In Step S30, a
conductor line 38 is formed to connect the first ohmic contact
layer E1 and the second ohmic contact layer E2 to each other.
[0018] In the present invention, the second base plate 35 comprises
a non-conductive plate and may selectively uses a
light-transmitting plate or a non-light-transmitting plate.
[0019] The step of removing a portion of the epitaxial layer 32
comprises removing parts of the epitaxial layer 32 on a first side
edge and a second side edge in order to expose portions of a
surface of the conductive oxide layer 33 to allow for disposing the
third ohmic contact layer E3 after the formation of the insulation
layer 37.
[0020] The step of removing a portion of the first bonding metal
layer 34, the second bonding metal layer 36, and the conductive
oxide layer 33 comprises removing a part of the first bonding metal
layer 34 on the first side edge, a part of the second bonding metal
layer 36 on the first side edge, and apart of the conductive oxide
layer 33 on the first side edge to allow for, after the removal,
forming the insulation layer 37 and disposing the first ohmic
contact layer E1 on a surface of the second base plate 35.
[0021] It is noted that as shown in FIG. 3F, after the portions of
the insulation layer 37 are removed, insulation layers 371, 372 are
formed to respectively cover a part of a surface of the second base
plate 35 and a part of a surface of the epitaxial layer 32 and
cover a part of the first bonding metal layer 34 on the first side
edge, a part of the second bonding metal layer 36 on the first side
edge, and a part of the conductive oxide layer 33 on the first side
edge.
[0022] Further, the first ohmic contact layer E1, the second ohmic
contact layer E2, and the third ohmic contact layer E3 do not need
to be formed in a specific sequence and may be formed at the same
time after the formation of the insulation layers 371, 372.
[0023] In the above steps, reduction of a thickness of the second
base plate 35 is further included in order to reduce an overall
thickness of the light-emitting device 3. The overall thickness of
the light-emitting device 3 is set between 80 and 350 micrometers
and an actual thickness can be determined according to the needs
for practical design and fabrication, such as it would be far less
than a thickness of a prior art light-emitting device. The
reduction of thickness of the second base plate 35 can be done just
to allow for electrical connection, by means of silver glue or
solder paste, with signals of a circuit board and ohmic contact
layers and allows for bonding, through adhering techniques, of the
light-emitting device 3 to the circuit board. The adhering
techniques comprise surface mounting techniques and the present
invention is not limited thereto.
[0024] Further, in the present invention, the conductor line
comprises any electrically conductive material for transmission of
signals of the first ohmic contact layer E1 and the second ohmic
contact layer E2. Thus, by using the conductor line 38 to transmit
electrical conduction of the first ohmic contact layer E1 and the
second ohmic contact layer E2, rather than using wiring bonding
process to connect the first ohmic contact layer E1 and the second
ohmic contact layer E2, the operation of packaging the
light-emitting device can be simplified and as such, the purpose of
size reduction and thinning can be achieved, allowing for
applications to the technical field of chip scale package.
[0025] Referring to FIG. 4, a schematic view is given to illustrate
a structure of a light-emitting device according to the present
invention. The light-emitting device 4 comprises a base plate 41, a
bonding metal layer 42, a conductive oxide layer 43, an epitaxial
layer 44, insulation layers 451, 452, a first ohmic contact layer
E1, a second ohmic contact. layer E2, a third ohmic contact layer
E3, and a conductor line 46. The bonding metal layer 42 is disposed
on a surface of a first part of the base plate 41. The conductive
oxide layer 43 is disposed on the bonding metal layer 42. The
epitaxial layer 44 is disposed on a surface of a first part. of the
conductive oxide layer 43. The insulation layer 451 is disposed on
a first side edge of the bonding metal layer 42, the conductive
oxide layer 43, and the epitaxial layer 44 the first side edge, and
is also disposed on a surface of a first part of the epitaxial
layer 44. The first ohmic contact layer E1 is disposed on a surface
of a second part of the. base plate 41. The second ohmic contact
layer E2 is disposed on a surface of a second part of the epitaxial
layer 44. The third ohmic contact layer E3 is disposed on a surface
of a second part of the conductive oxide layer 43. The conductor
line 46 electrically connects the first ohmic contact layer E1 and
the second ohmic contact layer E2 to each other.
[0026] Referring to FIG. 5, a schematic view is given to illustrate
a structure of another light-emitting device according to the
present invention. Based on the above description, the
light-emitting device of the present invention may further
comprises a non-conductive oxide layer 47 disposed between the
epitaxial layer 44 and the conductive oxide layer 43. The
non-conductive oxide layer 47 comprises at least one of silicon
nitride (SiNy), silicon oxynitride (SiON) or silicon dioxide.
Further, the non-conductive oxide layer 47 comprises at least one
via 471 connecting the epitaxial layer 44 and the conductive oxide
layer 43 in order to form ohmic contact with the epitaxial layer
44. Further, the via 471 is a metallic material, including metallic
materials, such as zinc gold (AuZn), beryllium gold (AuBe) chromium
(Cr) or gold (Au).
[0027] In an embodiment of the present invention, the base plate 41
comprises a non-conductive plate. The non-conductive plate
comprises a ceramic plate, an aluminum nitride plate, or an
aluminum oxide plate. In addition, in the present invention, the
base plate 41 can be a light-transmitting plate or a
non-light-transmitting plate.
[0028] The insulation layer 451 comprises silicon dioxide or
silicon nitride for isolating the first ohmic contact layer E1 and
the second ohmic contact layer E2. In another embodiment of the
present invention, the insulation layer 452 is further included,
disposed on a surface of a third part of the epitaxial layer 44 and
between a second side edge of the epitaxial layer 44 and the third
ohmic contact layer E3 to isolate the third ohmic contact layer E3
for preventing shorting.
[0029] The conductor line 46 has a width less than a diameter of a
solder ball used in a wire bonding process. Generally, the solder
ball used in a wire bonding process has a diameter that is greater
than 100 um; however, in the present invention, since no wire
bonding is necessary, it is possible to easily make a conductor
line of any desired width according to practical needs for design
and fabrication, such as a conductor line having a width greater
than 5 micrometers. In comparison, this is far less than the
diameter of the solder ball so that an effect of saving cost can be
achieved.
[0030] The light-emitting device 4 is bonded to a circuit board by
means of adhering techniques, and the circuit board is electrically
connected with the second ohmic contact layer E2 and the third
ohmic contact layer E3, and silver glue or solder paste is used to
electrically connect the conductor line 46 and the third ohmic
contact layer E3. In the present invention, the light-emitting
device 4 has an overall thickness that is between 80 and 350
micrometers and an actual thickness can be determined according to
practical design and fabrication, and in comparison with the prior
art, the thickness of the light-emitting device can be greatly
reduced.
[0031] In summary, compared to the prior art, where a metal ball is
disposed on an electrode and a recess is provided for the purposes
of making the electrodes identical, in height, to each other, the
present invention involves a process of providing a conductor line
to more precisely control the height of electrode so as to prevent
an issue associated with height difference of electrodes. Further,
the light-emitting device of the present invention uses the process
of providing a conductor line to connect an ohmic contact layer,
instead of wire bonding, so that a package process required by wire
bonding can be eliminated to thereby reduce the size of the
light-emitting device. Further, the light-emitting device of the
present invention, after the formation of the conductor line on the
ohmic contact layer, allows for performance of a step of directly
bonding to a circuit board so as to reduce the package size and
simplify equipment necessary for the package process to thereby
further lower down fabrication costs, achieving the effects of
simplification of operation and fast fabrication, allowing for wide
application to the technical field of chip size package.
[0032] Although the present invention has been described with
reference to the preferred embodiments thereof, it is apparent to
those skilled in the art that a variety of modifications and
changes may be made without departing from the scope of the present
invention which is intended to be defined by the appended
claims.
* * * * *