非掺杂半绝缘LECGaAs的光电流谱

Photocurrent Spectra of Undoped LECSIGaAs

研究了非掺杂半绝缘ＬＥＣＧａＡｓ的非本征室温（３００Ｋ）光电流谱，在０．４０～０．７０ｅＶ范围发现了一个光响应宽带Ｍ１。Ｍ１带在０．４６、０．４９、０．５６、０．６５和０．６９ｅＶ处出现五个峰，其中０．４６、０．４９、０．５６和０．６９ｅＶ峰的起始阈值分别为０．４４、０．４７、０．５１和０．６７ｅＶ。本文讨论了Ｍ１带的起源，提出了０．４４、０．４７和０．５１ｅＶ光电离阈值与铜受主、ＥＬ３和氧施主间的可能联系，并研究了Ｍ１带与ＧａＡｓ场效应晶体管漏－源电流光响应特性的关系。

Extrinsic photocurrent spectra of undoped LECSIGaAs have been measured to investigate the deep levels in this material.A broad photocurrent response band M 1 ranging from 0 40 to 0 70 eV has been observed.M 1 band reveals five peaks at 0 46,0 49,0 56,0 65 and 0 69 eV,respectively.The onset thresholds for the 0 46,0 49,0 56 and 0 69 eV peaks are 0 44,0 47,0 51 and 0 67 eV,respectively.It is likely that M 1 band is due to different deep levels and each of these deep levels has a concentration larger than 10 14 cm -3 .The origin of M 1 band is discussed and possible associations of the 0 44,0 47 and 0 51 eV thresholds with copper acceptor,EL3 and oxygen donor are presented.The relationship between M 1 band and the photoresponse behavior of drain current of GaAs field effect transistor was also investigated.