Abstract

We analyze the asymmetric delta-doping dependence of nonlinear electron mobility μ of GaAs|In_xGa_{1 –x}As double quantum-well pseudo-morphic modulation doped field-effect transistor structure. We solve the Schrodinger and Poisson’s equations self-consistently to obtain the sub-band energy levels and wave functions. We consider scatterings due to the ionized impurities (IMP), alloy disorder (AL), and interface roughness (IR) to calculate μ for a system having double sub-band occupancy, in which the inter-sub-band effects play an important role. Considering the doping concentrations in the barriers towards the substrate and surface sides as N_d1 and N_d2, respectively, we show that variation of N_d1 leads to a dip in μ near N_d1 = N_d2, at which the resonance of the sub-band states occurs. A similar dip in μ as a function of N_d1 is also obtained at N_d1 = N_d2 by keeping (N_d1 + N_d2) unchanged. By increasing the central barrier width and well width, the dip in μ becomes sharp. We note that even though the overall μ is governed by the IMP- and AL-scatterings, the dip in μ is mostly affected through substantial variation of the sub-band mobilities due to IR-scattering near the resonance. Our results of nonlinear electron mobility near the resonance of sub-band states can be utilized for the performance analysis of GaAs|InGaAs pseudo-morphic quantum-well field-effect transistors.

中文翻译：

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GaAs | In x Ga 1 – x耦合量子阱伪态MODFET结构中的掺杂依赖性非线性电子迁移率

摘要

我们分析了GaAs | In _x Ga _{1 – x} As双量子阱伪态调制掺杂的场效应晶体管结构的非线性电子迁移率μ的非对称增量掺杂依赖性。我们自洽地求解Schrodinger和Poisson方程，以获得子带能级和波函数。我们考虑由离子化杂质（IMP），合金无序（AL）和界面粗糙度（IR）引起的散射，以计算具有双子带占有率的系统的μ，其中子带间效应起着重要作用。将势垒中朝向衬底和表面侧的掺杂浓度视为N _{d 1}和N _{d 2}分别表明，N _{d 1的}变化会导致μ接近N _{d 1} = N _{d 2}下降，此时子带状态会发生谐振。在μA类似倾角的一个函数ñ _{d 1}也以得到Ñ _{d 1} = Ñ _{d 2}通过保持（Ñ _{d 1} + Ñ _{d 2}）保持不变。通过增加中心势垒宽度和阱宽度，μ的下降变陡。我们注意到，即使整体μ受IMP和AL散射支配，μ的下降主要受子带迁移率的实质性变化影响，这是由于共振附近的IR散射引起的。我们在子带态共振附近的非线性电子迁移率结果可用于GaAs | InGaAs伪形量子阱场效应晶体管的性能分析。