2002 Fiscal Year Annual Research Report

六方晶系ワイドギャップ化合物半導体の極性制御による光電子物性の飛躍的改善の研究

Research Project

Project/Area Number	13450121
Research Institution	Chiba University
Principal Investigator	吉川明彦千葉大学, 工学部, 教授 (20016603)
Co-Investigator(Kenkyū-buntansha)	石谷善博千葉大学, 工学部, 助教授 (60291481)
Keywords	III-V族窒化物 / エピタキシー / 結晶極性 / ワイドギャップ化合物半導体 / 窒化ガリウム / 窒化アルミニュウム / 酸化亜鉛 / 分子線エピタキシー
Research Abstract	昨年度までの実績をもとに、窒化物系および酸化物系化合物の極性制御および物性制御について以下のよう検討を進めた。 (1)窒化物系材料の中で最も小さいバンドギャップを有するInNについて、GaNの極性制御の知見をもとに、エピタキシへの極性の影響を検討し、世界に先駆けてInNのエピタキシ機構を明らかにし、高品質エピ膜の高速成長を実現した。この中で、InNのエピタキシはAINやGaNの場合と全く異なり、窒素極性(-C)の場合のほうがIn極性(+C)の場合よりもエピタキシおよび物性制御が容易であることが明らかになった。これはInNの窒素解離圧が高いために、窒素の膜中への取り込み過程がエピタキシプロセスを決めているためであり、窒素極性の場合のほうが100度程度高い温度でのエピタキシが可能であることに起因していることを示した。また、得られた高品質InNエピ膜の光学的特性評価から、そのエネルギーバンドギャップが従来報告の1.9eVではなく、およそ0.75eV程度であることを明らかにした。 (2)窒化を施したc面サファイア基板上へのGaNの窒素(-C)からの極性転換として、これまで提案してきた2分子層Al挿入効果の再現性・確実性を高めるために、まず高温でAlを堆積し、次に極性転換のためのGaN緩衝層の低温堆積することの効果を検討した。その結果、高温堆積によりAlの表面マイグレーションが促進され均一性にすぐれること、また、GaN緩衝層はおよそ800度以下でないとAl自体が窒化されてしまい、極性転換ができないとがわかった。 (3)ZnOの極性制御および回転ドメイン構造制御に関して、c面サファイアの窒化が極めて有効であることを明らかにした。これは、窒化により基板とエピタキシ関係が定まった窒素極性の薄いAIN層が形成されているためであることを明らかにした。

Research Products

(19 results)

All Other

All Publications (19 results)

[Publications] K.Xu, N.Yano, A.W.Jia, K.Takahashi, A.Yoshikawa: "Polarity Control of GaN Grown on Sapphire Substrate by RF-MBE"J.Crystal Growth. Vol.237-2 39-P2. 1003-1007 (2002)
[Publications] K.Xu, W.Terashima, T.Hata, N.Hashimoto, Y.Ishitani, A.Yoshikawa: "Step-Flow Growth of InN on N-Polarity GaN Template by Molecular Beam Epitaxy with Growth Rate of 1.3μm/Hour"Phys.Stat.Sol.(c). Vol.0 No.1. 377-381 (2002)
[Publications] K.Xu, N.Yano, A.W.Jia, K.Takahashi, A.Yoshikawa: "In-situ Real-time Analysis on Strain Relaxation Process in GaN Growth on Sapphire by RF-MBE"J.Crystal Growth. Vol.237-2 39-P2. 998-1002 (2002)
[Publications] D.H.Lim, K.Xu, S.Arima, A.Yoshikawa, K.Takahashi: "Polarity conversion of GaN films by trimethyl-Aluminum preflow in low-pressure MOVPE growth"J.Appl.Phys.. Vol.91 No.10. 6461 (2002)
[Publications] A.Yoshikawa, K.Xu, Y.Taniyasu, K.Takahashi: "Spectroscopic Ellipsometry In-situ Monitoring/control of GaN Epitaxial Growth in MOVPE and MBE"Phys.Stat.Sol.(a). Vol.190 No.1. 33-41 (2002)
[Publications] A.Yoshikawa, K.Xu: "Polarity selection process and polarity manipulation of GaN in MOVPE and RF-MBE growth"Thin Solid Films. Vol.412. 38-43 (2002)
[Publications] A.Yoshikawa, K.Xu: "Polarity controlled growth of III-nitrides and their potential applications in optoelectronic devices"Optics in Information Systems. 4 (2002)
[Publications] H.Kumada, S.Suzuki, Y.Kaifuchi, Y.Ishitani, A.Yoshikawa: "MBE Growth of Hexagonal CdS on GaAs(111)B Substrate"Proceedings of the First Asia-Pacific Workshop on Widegap Semiconductors. 312-313 (2003)
[Publications] Y.Ishitani, Y.Arita, N.Yoshida, H.Masuyama, A.Yoshikawa: "Step flow growth procedure for AIN layer on 6H-SiC substrate by MOVPE"Proceedings of the First Asia-Pacific Workshop on Widegap Semiconductors. 284-287 (2003)
[Publications] K.Xu, A.Yoshikawa: "Effect of crystal polarity on InN growth by molecular beam epitaxy"Appl.Phys.Lett.. (in print). (2003)
[Publications] A.Yoshikawa, K.Xu: "In-situ Monitoring of Epitaxy Processes in MBE and MOVPE of GaN and AlN and Their Polarity Manipulation"Optical Materials. (in print). (2003)
[Publications] Xiaolong Du, M.Murakami, H.Iwaki, Y.Ishitani, A.Yoshikawa: "Effects of Sapphire(0001)Surface Modification by Gallium Pre-Exposure on the Growth of High-Quality Epitaxial ZnO Film"Jpn.J.Appl.Phys. Vol.41. 1043-1045 (2002)
[Publications] Xinqiang Wang, H.Iwaki, M.Murakami, Xiaolong Du, Y.Ishitani, A.Yoshikawa: "Molecular Beam Epitaxy Growth of Single-Domain and High-Quality ZnO Layers on Nitrided (0001) Sapphire Surface"Jpn.J.Appl.Phys. Vol.42. 99-101 (2002)
[Publications] A.Yoshikawa, K.Xu: "In situ investigation for polarity-controlled epitaxy processes of GaN and AIN in MBE and MOVPE growth"Optidal Materials. Vol.23. (2003)
[Publications] A.Yoshikawa, Y.Ishitani, K.Xu: "InN project as CREST program of JST : "New evolution in Nano-processes/Nano-devices Focused on MBE-grown InN-based III -Nitrides"Proceedings of the First Asia-Pacific Workshop Widegap Semiconductors. 31 (2003)
[Publications] K.Xu, Y.Ishitani, A.Yoshikawa: "Growth and Properties of InN Epilayers by RF-MBE with In-situ Monitoring by RHEED, Spectroscopic Ellipsometry, and CAICISS"Proceedings of the First Asia-Pacific Workshop on Widegap Semiconductors. 33 (2003)
[Publications] Xinqiang WANG, H.Iwaki, Y.Ishitani, A.Yoshikawa: "MBE-grown ZnO films on sapphire with GaN buffer layer"Proceedings of the First Asia-Pacific Workshop on Widegap Semiconductors. 304 (2003)
[Publications] S.Suzuki, T.Nemoto, Y.Kaifuchi, Y.Ishitani, A.Yoshikawa: "MBE Growth and Characterization of Hexagonal ZnCdSe Layers on GaAs(111)-A and -B Substrates"physica status solidi (a). Vol 192,No1. 195-200 (2002)
[Publications] S.Suzuki, H.Kumada, Y.Kaifuchi, Y.Takazawa, Y.Ishitani, A.Yoshikawa: "Optical Properties of Hexagonal CdS Layers Grown on GaAs(111)B"Proceedings of the First Asia-Pacific Workshop on Widegap Semiconductors. 314-317 (2003)

2002 Fiscal Year Annual Research Report

六方晶系ワイドギャップ化合物半導体の極性制御による光電子物性の飛躍的改善の研究

Principal Investigator

吉川 明彦 千葉大学, 工学部, 教授 (20016603)

Research Products

[Publications] K.Xu, N.Yano, A.W.Jia, K.Takahashi, A.Yoshikawa: "Polarity Control of GaN Grown on Sapphire Substrate by RF-MBE"J.Crystal Growth. Vol.237-2 39-P2. 1003-1007 (2002)

[Publications] K.Xu, W.Terashima, T.Hata, N.Hashimoto, Y.Ishitani, A.Yoshikawa: "Step-Flow Growth of InN on N-Polarity GaN Template by Molecular Beam Epitaxy with Growth Rate of 1.3μm/Hour"Phys.Stat.Sol.(c). Vol.0 No.1. 377-381 (2002)

[Publications] K.Xu, N.Yano, A.W.Jia, K.Takahashi, A.Yoshikawa: "In-situ Real-time Analysis on Strain Relaxation Process in GaN Growth on Sapphire by RF-MBE"J.Crystal Growth. Vol.237-2 39-P2. 998-1002 (2002)

[Publications] D.H.Lim, K.Xu, S.Arima, A.Yoshikawa, K.Takahashi: "Polarity conversion of GaN films by trimethyl-Aluminum preflow in low-pressure MOVPE growth"J.Appl.Phys.. Vol.91 No.10. 6461 (2002)

[Publications] A.Yoshikawa, K.Xu, Y.Taniyasu, K.Takahashi: "Spectroscopic Ellipsometry In-situ Monitoring/control of GaN Epitaxial Growth in MOVPE and MBE"Phys.Stat.Sol.(a). Vol.190 No.1. 33-41 (2002)

[Publications] A.Yoshikawa, K.Xu: "Polarity selection process and polarity manipulation of GaN in MOVPE and RF-MBE growth"Thin Solid Films. Vol.412. 38-43 (2002)

[Publications] A.Yoshikawa, K.Xu: "Polarity controlled growth of III-nitrides and their potential applications in optoelectronic devices"Optics in Information Systems. 4 (2002)

[Publications] H.Kumada, S.Suzuki, Y.Kaifuchi, Y.Ishitani, A.Yoshikawa: "MBE Growth of Hexagonal CdS on GaAs(111)B Substrate"Proceedings of the First Asia-Pacific Workshop on Widegap Semiconductors. 312-313 (2003)

[Publications] Y.Ishitani, Y.Arita, N.Yoshida, H.Masuyama, A.Yoshikawa: "Step flow growth procedure for AIN layer on 6H-SiC substrate by MOVPE"Proceedings of the First Asia-Pacific Workshop on Widegap Semiconductors. 284-287 (2003)

[Publications] K.Xu, A.Yoshikawa: "Effect of crystal polarity on InN growth by molecular beam epitaxy"Appl.Phys.Lett.. (in print). (2003)

[Publications] A.Yoshikawa, K.Xu: "In-situ Monitoring of Epitaxy Processes in MBE and MOVPE of GaN and AlN and Their Polarity Manipulation"Optical Materials. (in print). (2003)

[Publications] Xiaolong Du, M.Murakami, H.Iwaki, Y.Ishitani, A.Yoshikawa: "Effects of Sapphire(0001)Surface Modification by Gallium Pre-Exposure on the Growth of High-Quality Epitaxial ZnO Film"Jpn.J.Appl.Phys. Vol.41. 1043-1045 (2002)

[Publications] Xinqiang Wang, H.Iwaki, M.Murakami, Xiaolong Du, Y.Ishitani, A.Yoshikawa: "Molecular Beam Epitaxy Growth of Single-Domain and High-Quality ZnO Layers on Nitrided (0001) Sapphire Surface"Jpn.J.Appl.Phys. Vol.42. 99-101 (2002)

[Publications] A.Yoshikawa, K.Xu: "In situ investigation for polarity-controlled epitaxy processes of GaN and AIN in MBE and MOVPE growth"Optidal Materials. Vol.23. (2003)

[Publications] A.Yoshikawa, Y.Ishitani, K.Xu: "InN project as CREST program of JST : "New evolution in Nano-processes/Nano-devices Focused on MBE-grown InN-based III -Nitrides"Proceedings of the First Asia-Pacific Workshop Widegap Semiconductors. 31 (2003)

[Publications] K.Xu, Y.Ishitani, A.Yoshikawa: "Growth and Properties of InN Epilayers by RF-MBE with In-situ Monitoring by RHEED, Spectroscopic Ellipsometry, and CAICISS"Proceedings of the First Asia-Pacific Workshop on Widegap Semiconductors. 33 (2003)

[Publications] Xinqiang WANG, H.Iwaki, Y.Ishitani, A.Yoshikawa: "MBE-grown ZnO films on sapphire with GaN buffer layer"Proceedings of the First Asia-Pacific Workshop on Widegap Semiconductors. 304 (2003)

[Publications] S.Suzuki, T.Nemoto, Y.Kaifuchi, Y.Ishitani, A.Yoshikawa: "MBE Growth and Characterization of Hexagonal ZnCdSe Layers on GaAs(111)-A and -B Substrates"physica status solidi (a). Vol 192,No1. 195-200 (2002)

[Publications] S.Suzuki, H.Kumada, Y.Kaifuchi, Y.Takazawa, Y.Ishitani, A.Yoshikawa: "Optical Properties of Hexagonal CdS Layers Grown on GaAs(111)B"Proceedings of the First Asia-Pacific Workshop on Widegap Semiconductors. 314-317 (2003)

吉川明彦千葉大学, 工学部, 教授 (20016603)