正电子湮没谱和光致发光谱研究掺锌GaSb质子辐照缺陷

用正电子湮没谱和光致发光谱研究了质子辐照后掺锌GaSb中的缺陷.通过分析正电子的缺陷寿命τ₂及强度I₂的变化发现,在高能质子的辐照下产生了双空位缺陷V_GaV_Sb,可能同时产生了小的空位团.正电子平均寿命τ_av和S参数随着质子辐照剂量的变化也证明了这一结论.通过分析不同质子辐照剂量下掺锌GaS

Defects in proton-irradiated Zn-doped GaSb studied by positron annihilation and photoluminescence

Positron annihilation spectroscopy(PAS)and photoluminescence (PL) have been adopted to study defects in proton-irradiatied Zn-doped GaSb. A monovacancy V_Ga having a lifetime of 293 ps was observed in the non-irradiated sampls and a divacancy V_GaV_Sb with a tifetime of 333 ps was identified in the proton-irradiated samples when the fluence reached 3×10¹⁵ cm^-2.The PL results reveal that the acceptor Zn is not related with proton irradiation-induced defects, which act as non-radiation recombination centers in the samples. The acceptor level of Zn in GaSb has been calculated from the PL spectra. After proton irradiation, interstitial monatomic hydrogen in a negative charge state (Hi^-) in GaSb has been found, which acts as a shallow-acceptor. Annealing experiments indicated that the as-grown and proton-irradiated samples have different annealing behaviors, the reason for which was attributed to the existence of monatomic hydrogen interstitials in the proton-irradiated samples.