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赝配ＩｎＧａＡｓ／ＩｎＡｌＡｓ调制掺杂异质结构可以获得很高的电子气面密度和电子迁移率，从而可以制成具有优越高频和低噪声特性的高电子迁移率晶体管（ＨＥＭＴ）．文中报道ＩｎＧａＡｓ／ＩｎＡｌＡｓ调制掺杂异质结构低温下纵向和横向磁阻随磁场强度变化的ＳｈｕｂｎｉｋｏｖｄｅＨａａｓ（ＳｄＨ）振荡和量子Ｈａｌ效应．对ＳｄＨ振荡曲线作了快速傅里叶变换，获得了二维电子气的能带结构和各能带上的电子气面密度．分析比较了顶层ＩｎＧａＡｓ不同掺杂情况对ＳｄＨ振荡的影响，结果发现顶层ＩｎＧａＡｓ重掺杂，会对表面态起屏蔽作用，从而使ＨＥＭＴ结构样品存在平行电导效应
The pseudomorphic InGaAs / InAlAs modulation doped heterostructure can obtain high electron gas density and electron mobility so as to form a high electron mobility transistor (HEMT) with superior high frequency and low noise characteristics. In this paper, ShubnikovdeHaas (SdH) oscillations and quantum Hal effect of the longitudinal and transverse reluctance changes with the magnetic field intensity are reported for InGaAs / InAlAs doped heterostructures. The SdH oscillation curve was subjected to fast Fourier transform to obtain the band structure of the two-dimensional electron gas and the electron gas density at each energy band. The influence of different doping of top InGaAs on the SdH oscillation is analyzed and compared. It is found that the doping of top InGaAs can shield the surface state and make the parallel conductance effect of HEMT structure sample