我们对N-GaAs和N-InP单晶及外延层在4.2K和77K下测定了光致发光谱,并用C-V法测定了电学参数,确定了未掺GaAs中的受主杂质主要是C和Si.通过室温离子注入Si和退火处理,证明了GaAs中1.403eV光谱峰与Si及砷空位V_(As)有关,结合化学及离子微探针分析结果,对未掺InP晶体光谱曲线研究指出,～1.38eV光谱峰是C受主引起的,而1.08和～1.2eV峰分别与磷空位V_p及铟空位V_(In)有关. We measured the photoluminescence spectra of single crystals of N-GaAs and N-InP and the epitaxial layers at 4.2K and 77K, and measured the electrical parameters by the CV method. It was confirmed that the acceptor impurities in the undoped GaAs are mainly C and Si .It is proved that the 1.403eV peak in GaAs is related to Si and arsenic vacancy V_ (As) by ion implantation of Si at room temperature and annealing treatment. Combined with the results of chemical and ion microprobe analysis, the spectral curve of undoped InP crystal shows that ~ The 1.38eV peak is due to C acceptor, while the 1.08 and ~ 1.2eV peaks are related to the P valence of phosphorus and the vacancy V_ (In) of indium, respectively.