MBE生长轻掺Si高迁移率GaAs材料的杂质补偿特性研究

Impurity Compensation Effects on Lightly Si-Doped GaAs Grown by MBE

本文报道了用ＭＢＥ生长轻掺Ｓｉ高迁移率ＧａＡｓ材料的杂质补偿特性实验研究．已得到７７Ｋ温度下迁移率为１６．２×１０４ｃｍ２／（Ｖ·ｓ）的ＧａＡｓ材料．样品的Ｈａｌｌ测量结果表明：在较低的杂质浓度范围（１×１０１３ｃｍ－３＜ｎ＜１×１０１５ｃｍ－３）内，在大体相同的生长温度（５９０℃左右）下，选择适当的生长速率Ｇｒ会增强对浅受主杂质的抑制作用，同时也会抑制Ｓｉ的自补偿效应，减小杂质的补偿度Ｎａ／Ｎｄ之值，从而提高ＭＢＥ外延ＧａＡｓ材料的迁移率．

Abstract An experimental study of compensation effects on lightly Si-doped high mobility GaAs grown by MBE has been carried out by Hall mobility and carrier concentration measurements. The mobility at 77K of GaAs has been reached as high as 16. 2×104cm2/(V.s). In the low doping range (n<1×105cm-3), the Na/Nd values decrese and electron mobilities increase with increase Gr at growth temperature of 590℃, this may be related to the reduced incorporation of compensating acceptors and Si autocompensation effects.