Precise structure control of GaAs/InGaP hetero-interfaces using metal organic vapor phase epitaxy and its abruptness analyzed by STEM

详细信息	查看全文 | 推荐本文 |

• 作者：Takayuki Nakano^a ; ^c ; ^{nakano@dpe.mm.t.u-tokyo.ac.jp} ; ^{ttnakan@ipc.shizuoka.ac.jp} ; Tomonari Shioda^b ; ^c ; Naomi Enomoto^c ; Eiji Abe^a ; Masakazu Sugiyama^c ; ^d ; Yoshiaki Nakano^c ; ^e ; Yukihiro Shimogaki^a ; ^c
• 关键词：A1. Growth models ; A1. Interfaces ; A1. Segregation ; A3. Metal organic vapor phase epitaxy ; B2. Semiconducting gallium arsenide ; B2. Semiconducting indium gallium phosphide
• 刊名：Journal of Crystal Growth
• 出版年：2012
• 期刊代码：49_00220248
• 类别：ch
• 出版时间：15 May, 2012
• 卷：347
• 期：1
• 页码：25-30
• 文件大小：1494 K

摘要

Fabrication of abrupt InGaP on GaAs (InGaP/GaAs) and GaAs on InGaP (GaAs/InGaP) hetero-interfaces has been difficult using metal organic vapor phase epitaxy (MOVPE) due to the exchange of P and As during the fabrication steps. Indium (In) surface segregation during InGaP growth also degrades the abruptness. Here, the MOVPE gas-switching sequence to fabricate atomically abrupt hetero-interfaces was optimized and the effects of this optimization on the hetero-interface abruptness were quantitatively evaluated using the Z-contrast method with scanning transmission electron microscopy (STEM). Results revealed that (a) in the fabrication of InGaP/GaAs hetero-interface, the GaAs top layer should be stabilized using As-source gas supply, and the excess As layer on GaAs should be terminated using an additional supply of Ga species, and (b) in the fabrication of GaAs/InGaP interface, the InGaP layer should be grown using the flow modulation method to suppress In surface segregation. In conclusion, the abruptness of hetero-interfaces of InGaP/GaAs and GaAs/InGaP was improved by using these optimized gas-switching sequences.