Effect of Ionized Impurities at Heterointerface on Concentration and Mobility of Two-Dimensional Electrons in Selectively Doped Heterojunction Structures

概要

論文の詳細を見る
The concentration N_s and the low-temperature mobility μ of two-dimensional electron gas in GaAs/AlGaAs selectively doped heterojunctions have been studied theoretically and experimentally for the case where ionized impurities are present at heterointerfaces. It is found that N_s scarcely changes when the concentration N_<IF> of interfacial impurities is below 1×10^<11> cm^<-2>, but it rapidly disappears at higher values of N_<IF> if the impurities are of the acceptor type. In contrast, the mobility is found to decrease substantially even when N_<IF> is as low as 10^9 cm^<-2>. Based on these results, a quantitative guideline is drawn on the acceptable level of contamination in ultrahighvacuum wafer processings including molecular beam epitaxial regrowth.
社団法人応用物理学会の論文
1994-09-15