Deep　Levels　in　Undoped　Semi-insulating　Liquid　Encapsulated　Czochralski　GaAs　Detected　by　Photocurrent　Measurement  

作　　者：杨瑞霞 胡凯生 李光平 周智慧 郭小兵 

出　　处：《Rare Metals》1997年第1期73-76,共4页稀有金属（英文版）

摘　　要：Deep levels in undoped semi insulating (SI) liquid encapsulated czochralski (LEC) GaAs were investigated through measuring extrinsic photocurrent spectra at 300 K. Two broad photoresponse bands M 1 and M 2 were observed in the range of 0.40 ～ 0.70 eV and the range from about 0.80 eV to the bandgap energy, respectively. It was shown that M 2 band is related to the photoionization of the deep defect EL2. M 1 band, which is reported for the first time, reveals several characteristic structures including five peaks at 0.46, 0.49, 0.56, 0.65 and 0.69 eV, respectively. The relative magnitudes of these peaks vary from sample to sample and are related to the thermal histories of the samples. These peaks are likely due to different deep levels.Deep levels in undoped semi insulating (SI) liquid encapsulated czochralski (LEC) GaAs were investigated through measuring extrinsic photocurrent spectra at 300 K. Two broad photoresponse bands M 1 and M 2 were observed in the range of 0.40 ～ 0.70 eV and the range from about 0.80 eV to the bandgap energy, respectively. It was shown that M 2 band is related to the photoionization of the deep defect EL2. M 1 band, which is reported for the first time, reveals several characteristic structures including five peaks at 0.46, 0.49, 0.56, 0.65 and 0.69 eV, respectively. The relative magnitudes of these peaks vary from sample to sample and are related to the thermal histories of the samples. These peaks are likely due to different deep levels.

关 键 词：GAAS LEC Photocurrent measurement Deep levels 

分 类 号：O614[理学—无机化学]