Improvement of life time of minority carriers in GaAs epi-layer grown on Ge substrate |
| |
Authors: | Ken Takahashi Shigeki Yamada Ryuichi Nakazono Yasushi Minagawa Takayuki Matsuda Tsunehiro Unno Shoji Kuma |
| |
Affiliation: | Advanced Research Center, Hitachi Cable, Ltd. 3550 Kidamari-cho, Tsuchiura-shi, Ibaraki-ken 300, Japan |
| |
Abstract: | A buffer layer structure on Ge substrate was studied for MOCVD growth of a high-quality GaAs layer. The buffer layer structure was designed taking into consideration both lattice constants and thermal expansion coefficients of GaAs and Ge. It consisted of a preliminarily grown thin layer of AlxGa1?xAs and a GaAs layer. Photoluminescence (PL) decay of a GaAs layer in an Alo0.2Ga0.8As-GaAs-Al0.2Ga0.8As double-hetero (DH) structure, which was grown on the buffer layer structure, was observed by time-resolved PL method to estimate the quality of epilayers in the DH structure. The PL decay time strongly depended on Al content (x) of the AlxGa1?x As preliminary layer, and the highest value was obtained when the x was 0.25. A PL decay time above 20 ns was successfully obtained for the DH structure grown on the buffer layer structure, which consisted of a 0.05 μm thick Al0.25Ga0.75As layer and a 1 μm thick GaAs layer. Although this value was half of that for the DH structure grown on GaAs substrate, it was much longer than the value of 3 ns for the DH structure grown on Ge substrate with a conventional GaAs buffer layer 1 μm thick. |
| |
Keywords: | Life time Minority carriers GaAs epi-layer Ge substrate |
本文献已被 ScienceDirect 等数据库收录! |
|