Quantitative analysis of potential barrier in GaInN ternary alloy semiconductor by microscopic spectroscopy and the mechanisms for high quantum efficiency

• Project/Area Number: 16K06264
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Electronic materials/Electric materials
• Research Institution: Yamaguchi University
• Principal Investigator: Kurai Satoshi 山口大学, 大学院創成科学研究科, 助教 (80304492)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000); Fiscal Year 2018: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2017: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2016: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
• Keywords: 顕微分光 / InGaN / 量子井戸構造 / ポテンシャル障壁 / 貫通転位 / 空間分解分光 / 窒化インジウムガリウム / 近接場光学顕微分光 / GaInN

Outline of Final Research Achievements

Spatial distribution of local high-energy emissions, which were observed at surface pits originating from threading dislocations in InGaN quantum well (QW) structures fabricated on c-plane sapphire substrates, was evaluated by scanning near-field optical microscopy (SNOM). Low temperature SNOM measurements revealed positional correlation between dark contrast and high-energy emission in blue and green QWs, that is direct observation of self-formation of energy barriers (200 to 300 meV in height) at dislocations. In addition, local high-energy emissions were also observed at threading dislocations in the AlGaN QW structures by cathodoluminescence method. In this case, no surface structure such as surface pits was observed, suggesting the different mechanism from that in the InGaN system.

Academic Significance and Societal Importance of the Research Achievements

本研究では、下地構造の異なる青色QW、青色に比べ効率の低い緑色QWおよび深紫外AlGaN QWにおいて貫通転位近傍に自己形成される特異なエネルギー障壁の観察および障壁高さの定量評価を行った。貫通転位近傍にエネルギー障壁が形成され、キャリアが欠陥において非発光となるのを抑制することが青色LEDの高効率化に有用とされており、観測された発光エネルギーの空間分布がデバイスの発光効率改善に繋がる可能性を示した。

Research Products

• [Journal Article] Nanoscopic spectroscopy of potential barriers formed around V-pits in InGaN/GaN multiple quantum wells on moderate temperature GaN pit expansion layers (2018)
  • Author(s): Kurai Satoshi、Okawa Kohei、Makio Ryoga、Nobata Genki、Gao Junji、Sugimoto Kohei、Okada Narihito、Tadatomo Kazuyuki、Yamada Yoichi
  • Journal Title: Journal of Applied Physics Volume: 124 Issue: 8
  • DOI: 10.1063/1.5043578
  • Peer Reviewed
• [Journal Article] Separation of effects of InGaN/GaN superlattice on performance of light-emitting diodes using mid-temperature-grown GaN layer (2018)
  • Author(s): Sugimoto Kohei、Okada Narihito、Kurai Satoshi、Yamada Yoichi、Tadatomo Kazuyuki
  • Journal Title: Japanese Journal of Applied Physics Volume: 57 Issue: 6 Pages: 062101-062101
  • DOI: 10.7567/jjap.57.062101
  • NAID: 210000149112
  • Peer Reviewed
• [Journal Article] Cathodoluminescence study on local high-energy emissions at dark spots in AlGaN/AlGaN multiple quantum wells (2018)
  • Author(s): S. Kurai, N. Imura, L. Jin, H. Miyake, K. Hiramatsu, Y. Yamada
  • Journal Title: Japanese Journal of Applied Physics Volume: 57 Issue: 6 Pages: 60311-60311
  • DOI: 10.7567/jjap.57.060311
  • NAID: 210000149104
  • Peer Reviewed / Open Access
• [Journal Article] Potential Barrier Formed Around Dislocations in InGaN Quantum Well Structures by Spot Cathodoluminescence Measurements (2017)
  • Author(s): Satoshi Kurai, Shota Higaki, Nobuto Imura, Kohei Okawa, Ryoga Makio, Narihito Okada, Kazuyuki Tadatomo, and Yoichi Yamada
  • Journal Title: Physica Status Solidi B Volume: - Issue: 5
  • DOI: 10.1002/pssb.201700358
  • Peer Reviewed
• [Journal Article] Spatially Resolved Spectroscopy of Blue and Green InGaN Quantum Wells by Scanning Near-Field Optical Microscopy (2017)
  • Author(s): Satoshi Kurai, Renma Mihara, Genki Nobata, Kohei Okawa, Narihito Okada, Kazuyuki Tadatomo, Yoshiki Yano, Toshiya Tabuchi, Koh Matsumoto, and Yoichi Yamada
  • Journal Title: Physica Status Solidi B Volume: - Issue: 5
  • DOI: 10.1002/pssb.201700322
  • Peer Reviewed
• [Presentation] 近接場光学顕微分法によるInGaN量子井戸構造におけるVピット近傍の特異構造PLマッピング (2019)
  • Author(s): 倉井聡, 岡田成仁, 只友一行, 山田陽一
  • Organizer: 第66回応用物理学会春季学術講演会
• [Presentation] 中温GaN 層上InGaN 多重量子井戸構造における V ピット近傍のポテンシャル障壁の顕微分光評価(2) (2019)
  • Author(s): 倉井聡, 大川康平, 槇尾凌我, 高俊吉, 林直矢, 岡田成仁, 只友一行, 山田陽一
  • Organizer: 第66回応用物理学会春季学術講演会
• [Presentation] Spatially resolved cathodoluminescence on dot-like high-energy emissions near threading dislocations in AlGaN multiple quantum wells (2018)
  • Author(s): Satoshi Kurai, Nobuto Imura, Li Jin, Hideto Miyake, and Yoichi Yamada
  • Organizer: International Workshop on Nitride Semiconductors 2018
  • Int'l Joint Research
• [Presentation] Temperature-dependent cathodoluminescence mapping of InGaN epitaxial layers with different In composition (2018)
  • Author(s): Satoshi Kurai, Ayumu Wakamatsu, and Yoichi Yamada
  • Organizer: International Workshop on Nitride Semiconductors 2018
  • Int'l Joint Research
• [Presentation] カソードルミネッセンスマッピング法によるAlGaN量子井戸構造の局所発光評価 (2018)
  • Author(s): LI JIN, 井村暢杜, 倉井聡, 三宅秀人, 平松和政, 山田陽一
  • Organizer: 2018年度 応用物理・物理系学会 中国四国支部合同学術講演会
• [Presentation] 近接場光学顕微分光法による緑色発光InGaN量子井戸構造における高エネルギー発光成分のエネルギー分割評価 (2018)
  • Author(s): 高俊吉, 野畑元喜, 大川康平, 槇尾凌我, 倉井聡, 岡田成仁, 只友一行, 矢野良樹, 田渕俊也, 松本功, 山田陽一
  • Organizer: 2018年度 応用物理・物理系学会 中国四国支部合同学術講演会
• [Presentation] 近接場光学顕微分光法による中温GaN上InGaN量子井戸構造におけるピット近傍のポテンシャル障壁 (2018)
  • Author(s): 槇尾凌我, 大川康平, 高俊吉, 野畑元喜, 倉井聡, 岡田成仁, 只友一行, 山田陽一
  • Organizer: 2018年度 応用物理・物理系学会 中国四国支部合同学術講演会
• [Presentation] 中温GaN 層上InGaN 多重量子井戸構造におけるVピット近傍のポテンシャル障壁の顕微分光評価 (2018)
  • Author(s): 倉井聡, 大川康平,槇尾凌我, 高俊吉, 野畑元喜, 岡田成仁, 只友一行, 山田陽一
  • Organizer: 第79回応用物理学会秋季学術講演会
• [Presentation] カソードルミネッセンス法によるAlGaN多重量子井戸構造の転位近傍の局所発光 (2018)
  • Author(s): 倉井聡, 井村暢杜, Li Jin, 三宅秀人, 平松和政, 山田陽一
  • Organizer: 第65回応用物理学会春季学術講演会
• [Presentation] 局所カソードルミネッセンスによるInGaN量子井戸構造のポテンシャル障壁評価 (2017)
  • Author(s): 倉井聡、檜垣翔大、岡田成仁、只友一行、山田陽一
  • Organizer: 第64回応用物理学会春季学術講演会
  • Place of Presentation: パシフィコ横浜(神奈川県横浜市)
  • Year and Date: 2017-03-14
• [Presentation] 近接場光学顕微分光測定による緑色発光InGaN量子井戸構造の高エネルギー発光成分の評価(2) (2017)
  • Author(s): 倉井聡, 三原練磨, 野畑元喜, 大川康平, 槇尾凌我, 岡田成仁, 只友一行, 矢野良樹, 田渕俊也, 松本功, 山田 陽一
  • Organizer: 第78回応用物理学会秋季学術講演会
• [Presentation] Potential Barrier formed around Dislocations in InGaN Quantum Well Structures by Spot Cathodoluminescence Measurements (2017)
  • Author(s): Satoshi Kurai, Shota Higaki, Narihito Okada, Kazuyuki Tadatomo, Yoichi Yamada
  • Organizer: The 12th International Conference on Nitride Semiconductors
• [Presentation] Spatial Resolved Spectroscopy of Blue and Green InGaN Quantum Wells by Scanning Near-Field Opitcal Microscopy (2017)
  • Author(s): Satoshi Kurai, Renma Mihara, Genki Nobata, Kohei Okawa, Narihito Okada, Kazuyuki Tadatomo, Yoshiki Yano, Toshiya Tabuchi, Koh Matsumoto, Yoichi Yamada
  • Organizer: The 12th International Conference on Nitride Semiconductors
• [Presentation] 近接場光学顕微分光測定による青色・緑色発光InGaN量子井戸構造の評価 (2016)
  • Author(s): 倉井聡、三原練磨、野畑元喜、大川康平、岡田成仁、只友一行、矢野良樹、田渕俊也、松本功、山田陽一
  • Organizer: 第77回応用物理学会秋季学術講演会
  • Place of Presentation: 朱鷺メッセ(新潟県新潟市)
  • Year and Date: 2016-09-13
• [Presentation] 緑色発光InGaN量子井戸構造に局所的に現れる高エネルギー側発光成分の評価 (2016)
  • Author(s): 野畑元喜、三原練磨、大川康平、倉井聡、岡田成仁、只友一行、矢野良樹、田渕俊也、松本功、山田陽一
  • Organizer: 2016年度応用物理・物理系学会中国四国支部合同学術講演会
  • Place of Presentation: 岡山大学津山キャンパス(岡山県岡山市)