INDIUM PHOSPHIDE SUBSTRATE, SEMICONDUCTOR EPITAXIAL WAFER, AND METHOD FOR PRODUCING INDIUM PHOSPHIDE SUBSTRATE | Matter42 Literature
Patent
Atlas literature
Patent
US 11,901,170 B2
INDIUM PHOSPHIDE SUBSTRATE, SEMICONDUCTOR EPITAXIAL WAFER, AND METHOD FOR PRODUCING INDIUM PHOSPHIDE SUBSTRATE
Shunsuke Oka, Hideki Kurita, Kenji Suzuki
JX METALS CORPORATION, Tokyo (JP)·Feb. 13, 2024·US
Claims
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
1 independent · 7 dependent
1
IndependentInPindium phosphide substrate
An indium phosphide substrate comprising a main surface for forming an epitaxial crystal layer and a back surface opposite to the main surface, wherein the back surface has a WARP value of 3.5 µm or less, as measured with the back surface of the indium phosphide substrate facing upward.
2
Dependent← claim 1InPindium phosphide substrate
The indium phosphide substrate according to claim 1, wherein the back surface has a WARP value of 1.8 to 3.5 µm, as measured with the back surface of the indium phosphide substrate facing upward.
A semiconductor epitaxial wafer comprising an epi-taxial crystal layer on the main surface of the indium phosphide substrate according to claim 1.
8
Dependent← claim 1InPindium phosphide substrate
A method for producing the indium phosphide substrate according to claim 1, comprising the steps of: cutting a wafer from an indium phosphide ingot with a wire saw; etching the cut wafer; chamfering an outer peripheral portion of the wafer after the etching; polishing at least one surface of the chamfered wafer; and etching the polished wafer, wherein the step of cutting the wafer from the indium phosphide ingot with the wire saw comprises a step of constantly delivering a new wire while reciprocating the wire in a horizontal direction, and moving a stage on which the indium phosphide ingot is placed in a vertical direction toward the wire, wherein a new wire delivering rate of the wire is from 10 to 60 m/min, a reciprocating rate of the wire is from 300 to 350 m/min, a vertical moving rate of the stage on which the indium phosphide ingot is placed is from 200 to 400 µm/min, and abrasive grains of the wire saw have a viscosity of from 300 to 400 mPa·s, wherein the step of etching the cut wafer comprises etching the cut wafer by a total of 5 to 15 µm from both sides, and
Worked examples
Embodiments described in the patent, grouped by the materials and process steps they use.
Examples 1-4 and Comparative Examples 1-2 (embedded in claim 5 table)
example section example
1 material1 process step
Indium phosphide substrates of varying diameters (76.2 mm and 100 mm) were produced using wire-saw cutting, etching, chamfering, polishing, and final etching steps. Process parameters varied include wafer thickness after slicing, etching amounts after cutting and after polishing, and wire saw conditions. WARP values of the back surface and main surface were measured. Examples 1-4 achieved WARP values within the claimed ranges; Comparative Examples 5-6 did not.
Device structures
Layer stacks claimed or described, ordered top of device to substrate.
indium phosphide substrate
InPsubstrate
semiconductor epitaxial wafer
epitaxial crystal layerepitaxial layer
InPsubstrate
Materials
Materials described outside the worked examples.
epitaxial crystal layer
Epitaxial Layer
Reported properties
Performance values and ranges asserted in the specification or claims.
Property
Value
Material
WARP value of back surface (claimed upper limit)
—
InP
WARP value of back surface (embodiment range, all diameters)
—
Cited prior art
Patents and literature cited by this patent (applicant and examiner references).
Cited patents · 16
US 4,844,047 A4,844,047 A * 7/1989 Brehm.................... C30B 33/00examiner
US 9,806,059 B19,806,059 B1 * 10/2017 Lee......................... H01L 21/78examiner
US 2015/0194319 A12015/0194319 A1 * 7/2015 Loboda............. H01L 21/02008examiner
US 2016/0351742 A12016/0351742 A1 * 12/2016 Akita...................... H01L 29/06examiner
Why these are connected
Related documents with shared materials, methods, properties, or citations.
INDIUM PHOSPHIDE SUBSTRATE, SEMICONDUCTOR EPITAXIAL WAFER, AND METHOD FOR PRODUCING INDIUM PHOSPHIDE SUBSTRATE
Shunsuke Oka, Hideki Kurita, Kenji Suzuki
JX METALS CORPORATION, Tokyo (JP)·Feb. 13, 2024·US
Claims
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
1 independent · 7 dependent
1
IndependentInPindium phosphide substrate
An indium phosphide substrate comprising a main surface for forming an epitaxial crystal layer and a back surface opposite to the main surface, wherein the back surface has a WARP value of 3.5 µm or less, as measured with the back surface of the indium phosphide substrate facing upward.
2
Dependent← claim 1InPindium phosphide substrate
The indium phosphide substrate according to claim 1, wherein the back surface has a WARP value of 1.8 to 3.5 µm, as measured with the back surface of the indium phosphide substrate facing upward.
A semiconductor epitaxial wafer comprising an epi-taxial crystal layer on the main surface of the indium phosphide substrate according to claim 1.
8
Dependent← claim 1InPindium phosphide substrate
A method for producing the indium phosphide substrate according to claim 1, comprising the steps of: cutting a wafer from an indium phosphide ingot with a wire saw; etching the cut wafer; chamfering an outer peripheral portion of the wafer after the etching; polishing at least one surface of the chamfered wafer; and etching the polished wafer, wherein the step of cutting the wafer from the indium phosphide ingot with the wire saw comprises a step of constantly delivering a new wire while reciprocating the wire in a horizontal direction, and moving a stage on which the indium phosphide ingot is placed in a vertical direction toward the wire, wherein a new wire delivering rate of the wire is from 10 to 60 m/min, a reciprocating rate of the wire is from 300 to 350 m/min, a vertical moving rate of the stage on which the indium phosphide ingot is placed is from 200 to 400 µm/min, and abrasive grains of the wire saw have a viscosity of from 300 to 400 mPa·s, wherein the step of etching the cut wafer comprises etching the cut wafer by a total of 5 to 15 µm from both sides, and
Worked examples
Embodiments described in the patent, grouped by the materials and process steps they use.
Examples 1-4 and Comparative Examples 1-2 (embedded in claim 5 table)
example section example
1 material1 process step
Indium phosphide substrates of varying diameters (76.2 mm and 100 mm) were produced using wire-saw cutting, etching, chamfering, polishing, and final etching steps. Process parameters varied include wafer thickness after slicing, etching amounts after cutting and after polishing, and wire saw conditions. WARP values of the back surface and main surface were measured. Examples 1-4 achieved WARP values within the claimed ranges; Comparative Examples 5-6 did not.
Device structures
Layer stacks claimed or described, ordered top of device to substrate.
indium phosphide substrate
InPsubstrate
semiconductor epitaxial wafer
epitaxial crystal layerepitaxial layer
InPsubstrate
Materials
Materials described outside the worked examples.
epitaxial crystal layer
Epitaxial Layer
Reported properties
Performance values and ranges asserted in the specification or claims.
Property
Value
Material
WARP value of back surface (claimed upper limit)
—
InP
WARP value of back surface (embodiment range, all diameters)
—
Cited prior art
Patents and literature cited by this patent (applicant and examiner references).
Cited patents · 16
US 4,844,047 A4,844,047 A * 7/1989 Brehm.................... C30B 33/00examiner
US 9,806,059 B19,806,059 B1 * 10/2017 Lee......................... H01L 21/78examiner
US 2015/0194319 A12015/0194319 A1 * 7/2015 Loboda............. H01L 21/02008examiner
US 2016/0351742 A12016/0351742 A1 * 12/2016 Akita...................... H01L 29/06examiner
Why these are connected
Related documents with shared materials, methods, properties, or citations.
INDIUM PHOSPHIDE SUBSTRATE, SEMICONDUCTOR EPITAXIAL WAFER, AND METHOD FOR PRODUCING INDIUM PHOSPHIDE SUBSTRATE
Shunsuke Oka, Hideki Kurita, Kenji Suzuki
JX METALS CORPORATION, Tokyo (JP)·Feb. 13, 2024·US
Claims
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
1 independent · 7 dependent
1
IndependentInPindium phosphide substrate
An indium phosphide substrate comprising a main surface for forming an epitaxial crystal layer and a back surface opposite to the main surface, wherein the back surface has a WARP value of 3.5 µm or less, as measured with the back surface of the indium phosphide substrate facing upward.
2
Dependent← claim 1InPindium phosphide substrate
The indium phosphide substrate according to claim 1, wherein the back surface has a WARP value of 1.8 to 3.5 µm, as measured with the back surface of the indium phosphide substrate facing upward.
A semiconductor epitaxial wafer comprising an epi-taxial crystal layer on the main surface of the indium phosphide substrate according to claim 1.
8
Dependent← claim 1InPindium phosphide substrate
A method for producing the indium phosphide substrate according to claim 1, comprising the steps of: cutting a wafer from an indium phosphide ingot with a wire saw; etching the cut wafer; chamfering an outer peripheral portion of the wafer after the etching; polishing at least one surface of the chamfered wafer; and etching the polished wafer, wherein the step of cutting the wafer from the indium phosphide ingot with the wire saw comprises a step of constantly delivering a new wire while reciprocating the wire in a horizontal direction, and moving a stage on which the indium phosphide ingot is placed in a vertical direction toward the wire, wherein a new wire delivering rate of the wire is from 10 to 60 m/min, a reciprocating rate of the wire is from 300 to 350 m/min, a vertical moving rate of the stage on which the indium phosphide ingot is placed is from 200 to 400 µm/min, and abrasive grains of the wire saw have a viscosity of from 300 to 400 mPa·s, wherein the step of etching the cut wafer comprises etching the cut wafer by a total of 5 to 15 µm from both sides, and
Worked examples
Embodiments described in the patent, grouped by the materials and process steps they use.
Examples 1-4 and Comparative Examples 1-2 (embedded in claim 5 table)
example section example
1 material1 process step
Indium phosphide substrates of varying diameters (76.2 mm and 100 mm) were produced using wire-saw cutting, etching, chamfering, polishing, and final etching steps. Process parameters varied include wafer thickness after slicing, etching amounts after cutting and after polishing, and wire saw conditions. WARP values of the back surface and main surface were measured. Examples 1-4 achieved WARP values within the claimed ranges; Comparative Examples 5-6 did not.
Device structures
Layer stacks claimed or described, ordered top of device to substrate.
indium phosphide substrate
InPsubstrate
semiconductor epitaxial wafer
epitaxial crystal layerepitaxial layer
InPsubstrate
Materials
Materials described outside the worked examples.
epitaxial crystal layer
Epitaxial Layer
Reported properties
Performance values and ranges asserted in the specification or claims.
Property
Value
Material
WARP value of back surface (claimed upper limit)
—
InP
WARP value of back surface (embodiment range, all diameters)
—
Cited prior art
Patents and literature cited by this patent (applicant and examiner references).
Cited patents · 16
US 4,844,047 A4,844,047 A * 7/1989 Brehm.................... C30B 33/00examiner
US 9,806,059 B19,806,059 B1 * 10/2017 Lee......................... H01L 21/78examiner
US 2015/0194319 A12015/0194319 A1 * 7/2015 Loboda............. H01L 21/02008examiner
US 2016/0351742 A12016/0351742 A1 * 12/2016 Akita...................... H01L 29/06examiner
Why these are connected
Related documents with shared materials, methods, properties, or citations.
INDIUM PHOSPHIDE SUBSTRATE, SEMICONDUCTOR EPITAXIAL WAFER, AND METHOD FOR PRODUCING INDIUM PHOSPHIDE SUBSTRATE
Shunsuke Oka, Hideki Kurita, Kenji Suzuki
JX METALS CORPORATION, Tokyo (JP)·Feb. 13, 2024·US
Claims
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
1 independent · 7 dependent
1
IndependentInPindium phosphide substrate
An indium phosphide substrate comprising a main surface for forming an epitaxial crystal layer and a back surface opposite to the main surface, wherein the back surface has a WARP value of 3.5 µm or less, as measured with the back surface of the indium phosphide substrate facing upward.
2
Dependent← claim 1InPindium phosphide substrate
The indium phosphide substrate according to claim 1, wherein the back surface has a WARP value of 1.8 to 3.5 µm, as measured with the back surface of the indium phosphide substrate facing upward.
A semiconductor epitaxial wafer comprising an epi-taxial crystal layer on the main surface of the indium phosphide substrate according to claim 1.
8
Dependent← claim 1InPindium phosphide substrate
A method for producing the indium phosphide substrate according to claim 1, comprising the steps of: cutting a wafer from an indium phosphide ingot with a wire saw; etching the cut wafer; chamfering an outer peripheral portion of the wafer after the etching; polishing at least one surface of the chamfered wafer; and etching the polished wafer, wherein the step of cutting the wafer from the indium phosphide ingot with the wire saw comprises a step of constantly delivering a new wire while reciprocating the wire in a horizontal direction, and moving a stage on which the indium phosphide ingot is placed in a vertical direction toward the wire, wherein a new wire delivering rate of the wire is from 10 to 60 m/min, a reciprocating rate of the wire is from 300 to 350 m/min, a vertical moving rate of the stage on which the indium phosphide ingot is placed is from 200 to 400 µm/min, and abrasive grains of the wire saw have a viscosity of from 300 to 400 mPa·s, wherein the step of etching the cut wafer comprises etching the cut wafer by a total of 5 to 15 µm from both sides, and
Worked examples
Embodiments described in the patent, grouped by the materials and process steps they use.
Examples 1-4 and Comparative Examples 1-2 (embedded in claim 5 table)
example section example
1 material1 process step
Indium phosphide substrates of varying diameters (76.2 mm and 100 mm) were produced using wire-saw cutting, etching, chamfering, polishing, and final etching steps. Process parameters varied include wafer thickness after slicing, etching amounts after cutting and after polishing, and wire saw conditions. WARP values of the back surface and main surface were measured. Examples 1-4 achieved WARP values within the claimed ranges; Comparative Examples 5-6 did not.
Device structures
Layer stacks claimed or described, ordered top of device to substrate.
indium phosphide substrate
InPsubstrate
semiconductor epitaxial wafer
epitaxial crystal layerepitaxial layer
InPsubstrate
Materials
Materials described outside the worked examples.
epitaxial crystal layer
Epitaxial Layer
Reported properties
Performance values and ranges asserted in the specification or claims.
Property
Value
Material
WARP value of back surface (claimed upper limit)
—
InP
WARP value of back surface (embodiment range, all diameters)
—
Cited prior art
Patents and literature cited by this patent (applicant and examiner references).
Cited patents · 16
US 4,844,047 A4,844,047 A * 7/1989 Brehm.................... C30B 33/00examiner
US 9,806,059 B19,806,059 B1 * 10/2017 Lee......................... H01L 21/78examiner
US 2015/0194319 A12015/0194319 A1 * 7/2015 Loboda............. H01L 21/02008examiner
US 2016/0351742 A12016/0351742 A1 * 12/2016 Akita...................... H01L 29/06examiner
Why these are connected
Related documents with shared materials, methods, properties, or citations.
WARP value of back surface (embodiment, 76.2 mm diameter)
—
InP
WARP value of back surface (embodiment, 50.8 mm diameter)
—
InP
InP substrate thickness (preferred range)
—
InP
InP substrate main surface maximum diameter
—
InP
Thickness
50–151 mm
—
Thickness
20–101 mm
—
Thickness
300–900 µm
—
Thickness
1.8–3.5 µm
—
Thickness
1.8–3.4 µm
—
Thickness
1.8–2.2 µm
—
Thickness
200–400 µm
—
Pressure
300–400 mPa
—
Thickness
5–15 µm
—
Thickness
8–15 µm
—
Thickness
≤ 300 µm
—
Thickness
≥ 900 µm
—
US 2018/0122749 A12018/0122749 A1 * 5/2018 Lee....................... H01L 21/486examiner
US 2018/0358221 A12018/0358221 A1 * 12/2018 Carlson............... H01L 29/2003examiner
US 2019/0157834 A12019/0157834 A1 * 5/2019 Clark................ H01L 21/02546examiner
US 2019/0189421 A12019/0189421 A1 6/2019 Yoshida et al.
US 2020/0203160 A12020/0203160 A1 * 6/2020 Fukugawa............ H01L 21/302examiner
US 2020/0227268 A12020/0227268 A1 * 7/2020 Wang...................... H01L 29/30examiner
US 2021/0035850 A12021/0035850 A1 * 2/2021 Shirley................... H01L 22/20examiner
US 2021/0217670 A12021/0217670 A1 * 7/2021 Yin......................... H01L 22/12examiner
US 2021/0257809 A12021/0257809 A1 * 8/2021 Clark.................... H01S 5/3201examiner
US 2021/0370459 A12021/0370459 A1 * 12/2021 Wang...................... H01L 29/34examiner
US 2022/0037516 A12022/0037516 A1 * 2/2022 Chen..................... H01L 29/205examiner
CN 109689946 ACN 109689946 A 4/2019
Cited non-patent literature · 1
International Search Report for PCT/JP2020/022197 (PCT/ISA/210) dated Aug. 25, 2020. Written Opinion of the International Searching Authority for PCT/JP2020/022197 (PCT/ISA/237) dated Aug. 25, 2020. Extended European Search Report dated Jun. 9, 2022 for corre- sponding Application No. 20880338.7. English translation of the International Preliminary Report on Patentability and Written Opinion of the International Searching Authority (Forms PCT/IB/338, PCT/IB/373 and PCT/ISA/237) for International Application No. PCT/JP2020/022197, dated Jun. 9, 2022.
WARP value of back surface (embodiment, 76.2 mm diameter)
—
InP
WARP value of back surface (embodiment, 50.8 mm diameter)
—
InP
InP substrate thickness (preferred range)
—
InP
InP substrate main surface maximum diameter
—
InP
Thickness
50–151 mm
—
Thickness
20–101 mm
—
Thickness
300–900 µm
—
Thickness
1.8–3.5 µm
—
Thickness
1.8–3.4 µm
—
Thickness
1.8–2.2 µm
—
Thickness
200–400 µm
—
Pressure
300–400 mPa
—
Thickness
5–15 µm
—
Thickness
8–15 µm
—
Thickness
≤ 300 µm
—
Thickness
≥ 900 µm
—
US 2018/0122749 A12018/0122749 A1 * 5/2018 Lee....................... H01L 21/486examiner
US 2018/0358221 A12018/0358221 A1 * 12/2018 Carlson............... H01L 29/2003examiner
US 2019/0157834 A12019/0157834 A1 * 5/2019 Clark................ H01L 21/02546examiner
US 2019/0189421 A12019/0189421 A1 6/2019 Yoshida et al.
US 2020/0203160 A12020/0203160 A1 * 6/2020 Fukugawa............ H01L 21/302examiner
US 2020/0227268 A12020/0227268 A1 * 7/2020 Wang...................... H01L 29/30examiner
US 2021/0035850 A12021/0035850 A1 * 2/2021 Shirley................... H01L 22/20examiner
US 2021/0217670 A12021/0217670 A1 * 7/2021 Yin......................... H01L 22/12examiner
US 2021/0257809 A12021/0257809 A1 * 8/2021 Clark.................... H01S 5/3201examiner
US 2021/0370459 A12021/0370459 A1 * 12/2021 Wang...................... H01L 29/34examiner
US 2022/0037516 A12022/0037516 A1 * 2/2022 Chen..................... H01L 29/205examiner
CN 109689946 ACN 109689946 A 4/2019
Cited non-patent literature · 1
International Search Report for PCT/JP2020/022197 (PCT/ISA/210) dated Aug. 25, 2020. Written Opinion of the International Searching Authority for PCT/JP2020/022197 (PCT/ISA/237) dated Aug. 25, 2020. Extended European Search Report dated Jun. 9, 2022 for corre- sponding Application No. 20880338.7. English translation of the International Preliminary Report on Patentability and Written Opinion of the International Searching Authority (Forms PCT/IB/338, PCT/IB/373 and PCT/ISA/237) for International Application No. PCT/JP2020/022197, dated Jun. 9, 2022.
WARP value of back surface (embodiment, 76.2 mm diameter)
—
InP
WARP value of back surface (embodiment, 50.8 mm diameter)
—
InP
InP substrate thickness (preferred range)
—
InP
InP substrate main surface maximum diameter
—
InP
Thickness
50–151 mm
—
Thickness
20–101 mm
—
Thickness
300–900 µm
—
Thickness
1.8–3.5 µm
—
Thickness
1.8–3.4 µm
—
Thickness
1.8–2.2 µm
—
Thickness
200–400 µm
—
Pressure
300–400 mPa
—
Thickness
5–15 µm
—
Thickness
8–15 µm
—
Thickness
≤ 300 µm
—
Thickness
≥ 900 µm
—
US 2018/0122749 A12018/0122749 A1 * 5/2018 Lee....................... H01L 21/486examiner
US 2018/0358221 A12018/0358221 A1 * 12/2018 Carlson............... H01L 29/2003examiner
US 2019/0157834 A12019/0157834 A1 * 5/2019 Clark................ H01L 21/02546examiner
US 2019/0189421 A12019/0189421 A1 6/2019 Yoshida et al.
US 2020/0203160 A12020/0203160 A1 * 6/2020 Fukugawa............ H01L 21/302examiner
US 2020/0227268 A12020/0227268 A1 * 7/2020 Wang...................... H01L 29/30examiner
US 2021/0035850 A12021/0035850 A1 * 2/2021 Shirley................... H01L 22/20examiner
US 2021/0217670 A12021/0217670 A1 * 7/2021 Yin......................... H01L 22/12examiner
US 2021/0257809 A12021/0257809 A1 * 8/2021 Clark.................... H01S 5/3201examiner
US 2021/0370459 A12021/0370459 A1 * 12/2021 Wang...................... H01L 29/34examiner
US 2022/0037516 A12022/0037516 A1 * 2/2022 Chen..................... H01L 29/205examiner
CN 109689946 ACN 109689946 A 4/2019
Cited non-patent literature · 1
International Search Report for PCT/JP2020/022197 (PCT/ISA/210) dated Aug. 25, 2020. Written Opinion of the International Searching Authority for PCT/JP2020/022197 (PCT/ISA/237) dated Aug. 25, 2020. Extended European Search Report dated Jun. 9, 2022 for corre- sponding Application No. 20880338.7. English translation of the International Preliminary Report on Patentability and Written Opinion of the International Searching Authority (Forms PCT/IB/338, PCT/IB/373 and PCT/ISA/237) for International Application No. PCT/JP2020/022197, dated Jun. 9, 2022.
WARP value of back surface (embodiment, 76.2 mm diameter)
—
InP
WARP value of back surface (embodiment, 50.8 mm diameter)
—
InP
InP substrate thickness (preferred range)
—
InP
InP substrate main surface maximum diameter
—
InP
Thickness
50–151 mm
—
Thickness
20–101 mm
—
Thickness
300–900 µm
—
Thickness
1.8–3.5 µm
—
Thickness
1.8–3.4 µm
—
Thickness
1.8–2.2 µm
—
Thickness
200–400 µm
—
Pressure
300–400 mPa
—
Thickness
5–15 µm
—
Thickness
8–15 µm
—
Thickness
≤ 300 µm
—
Thickness
≥ 900 µm
—
US 2018/0122749 A12018/0122749 A1 * 5/2018 Lee....................... H01L 21/486examiner
US 2018/0358221 A12018/0358221 A1 * 12/2018 Carlson............... H01L 29/2003examiner
US 2019/0157834 A12019/0157834 A1 * 5/2019 Clark................ H01L 21/02546examiner
US 2019/0189421 A12019/0189421 A1 6/2019 Yoshida et al.
US 2020/0203160 A12020/0203160 A1 * 6/2020 Fukugawa............ H01L 21/302examiner
US 2020/0227268 A12020/0227268 A1 * 7/2020 Wang...................... H01L 29/30examiner
US 2021/0035850 A12021/0035850 A1 * 2/2021 Shirley................... H01L 22/20examiner
US 2021/0217670 A12021/0217670 A1 * 7/2021 Yin......................... H01L 22/12examiner
US 2021/0257809 A12021/0257809 A1 * 8/2021 Clark.................... H01S 5/3201examiner
US 2021/0370459 A12021/0370459 A1 * 12/2021 Wang...................... H01L 29/34examiner
US 2022/0037516 A12022/0037516 A1 * 2/2022 Chen..................... H01L 29/205examiner
CN 109689946 ACN 109689946 A 4/2019
Cited non-patent literature · 1
International Search Report for PCT/JP2020/022197 (PCT/ISA/210) dated Aug. 25, 2020. Written Opinion of the International Searching Authority for PCT/JP2020/022197 (PCT/ISA/237) dated Aug. 25, 2020. Extended European Search Report dated Jun. 9, 2022 for corre- sponding Application No. 20880338.7. English translation of the International Preliminary Report on Patentability and Written Opinion of the International Searching Authority (Forms PCT/IB/338, PCT/IB/373 and PCT/ISA/237) for International Application No. PCT/JP2020/022197, dated Jun. 9, 2022.
