Elucidation of efficiency droop mechanism in nitride semiconductorbased light emitting devices by scanning near field optical microscopy

通过扫描近场光学显微镜阐明氮化物半导体发光器件的效率下降机制

• 批准号: 23686003
• 负责人: KANETA Akio
• 金额: $ 15.14万
• 依托单位: Kyoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Young Scientists (A)
• 财政年份: 2011
• 资助国家: 日本
• 起止时间: 2011 至 2012
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-23686003/
• 关键词: 走査プローブ顕微鏡; 半導体物性; マルチモード近接場分光; 過渡レンズ法; 効率ドループ

To clarify main factor of efficiency droop phenomena, we performed PL and time-resolved PL measurement using a scanning near field optical microscope. For the blue sample , although carriers overflow from localization centers under the high carrier density, the capture to nonradiative recombination centers (NRCs) hardly takes place because the potential barriers are formed around the NRCs. On the other hand, for the green sample, the increase of carrier density enhances the diffusion from the strong PL domains to the weak ones corresponding to high In composition area, where a large number of NRCs are distributed in association with threading dislocations. Such carrier recombination dynamics was found to be a major mechanism of the efficiency droop in the green sample due to the increase of both carrier lifetime and number of threading dislocations.

为了阐明效率下降现象的主要因素，我们使用扫描近场光学显微镜进行了光致发光和时间分辨光致发光的测量。对于蓝色样品，尽管在高载流子密度下载流子从局域化中心溢出，但几乎没有捕获到非辐射复合中心(NRCS)，因为势垒形成在NRCS周围。另一方面，对于绿色样品，随着载流子浓度的增加，增强了从强光致发光区向高成分区对应的弱发光区的扩散，其中大量的NRCs分布与线状位错有关。这种载流子复合动力学被发现是由于载流子寿命和穿线位错数目的增加而导致绿色样品中效率下降的主要机制。

项目成果

共焦点顕微鏡による高Al組成AlGaN/AlN量子井戸のPLマッピング

使用共焦显微镜对高铝成分 AlGaN/AlN 量子阱进行 PL 映射

• 作者: 岩田佳也;金田昭男;ライアン バナル;船戸 充;川上養一
• 通讯作者: 川上養一

Micromirror arrays to assess luminescent nano-objects

用于评估发光纳米物体的微镜阵列

• DOI: 10.1063/1.3589855
• 发表时间: 2011
• 期刊: Review of Scientific Instruments
• 影响因子: 1.6
• 作者: Y. Kawakami;A. Kanai;A. Kaneta;M. Funato;A. Kikuchi and K. Kishino
• 通讯作者: A. Kikuchi and K. Kishino

Instrumentation for dual-probe scanning near-field optical microscopy

• DOI: 10.1063/1.4737883
• 发表时间: 2012-08-01
• 期刊: REVIEW OF SCIENTIFIC INSTRUMENTS
• 影响因子: 1.6
• 作者: Kaneta, A.;Fujimoto, R.;Kawakami, Y.
• 通讯作者: Kawakami, Y.

Hydrostatic and uniaxial deformation potentials in aluminum nitride: Breakdown of the quasicubic approximation in AlN

氮化铝中的静水压和单轴变形势：AlN 中准三次近似的分解

• 作者: R. Ishii;A. Kaneta;M. Funato and Y. Kawakami
• 通讯作者: M. Funato and Y. Kawakami

InGaN/GaN量子井戸面内におけるキャリアの伝播・再結合過程の観測

InGaN/GaN量子阱平面内载流子传播和复合过程的观察

• 作者: T. Ohsawa;R. Shimizu;K. Iwaya;S. Shiraki;T. Hitosugi;塚崎 敦;西川恭平，金田昭男，船戸 充，川上養一
• 通讯作者: 西川恭平，金田昭男，船戸 充，川上養一