Semiconductor nanoheterostructures INALGAAS / INALAS / INAS metamorphic buffer layer on a substrate of gallium arsenide

摘要

The proposed utility model relates to a semiconductor nanoheterostructures InAlAs / InGaAs / GaAs high electron mobility type MNEMT (metamorphic high electron mobility transistor), used for manufacturing transistors and microwave monolithic integrated circuits millimeter waves. Object of the present utility model is to provide a so-called metamorphic nanogeterostruktur transistors with high electron mobility on GaAs substrates, device characteristics are not inferior characteristics nanoheterostructures InP substrates according to the maximum values ​​of the mobility and electron concentration in the channel, and transistors based on them - on the maximum operating frequency and minimum noise level. Technical result, allowing to perform the task, is to suppress the penetration dislocations in the active region nanoheterostructures transistor with high mobility of electrons and suppression of the development process microrelief surface during epitaxy process, leading to a decrease in surface roughness and heterojunctions nanoheterostructures, which reduces scattering of charge carriers at the roughness heterojunction and promotes carrier mobility two-dimensional electron gas. The result achieved by the use nanoheterostructures metamorphic buffer layer special original design, with a sharp step change in the mole fraction of indium arsenide in the layers of solid solutions constituting nanogeterostruktur, characterized in that inside nanoheterostructures introduced: the starting layer quaternary solid solution of In _1-xy Al _y Ga _x As (5, 2) stepwise increasing the lattice parameter immediately after formation of a buffer layer of gallium arsenide; three layered superlattice mechanically strained In _{1-xy Al y Ga x As /} In _1-y Al _y As (7,9,11, 2) with different average mole fraction of indium arsenide crystal lattice parameter, with the ratio of layer thickness ternary and quaternary solid solutions 2 to 1, 1 to 1 and 1 to 2 suppressing germination of misfit dislocations in the upper layers of the heterostructure and the development of surface microrelief heterostructure; terminating metamorphic layer ternary solid solution of In _1-y Al _y As (13, 2) stepwise increasing the lattice parameter to a desired final value; ultrathin layers of InAs (6, 8, 10, 12, 2), placed at the beginning of each step of increasing the lattice constant of the heterostructure, providing early formation of a network of misfit dislocations and their effective "healing" as vfaschivaniya heterostructure.