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In this work AlxIn1−xN/GaN heterostructure is considered taking into account the effects of spontaneous and piezoelectric polarizations on sheet carrier concentration versus alloy composition. It is found that piezoelectric polarization decreases from (14.8×10−6 C/cm2) to (−5.25×l0−6 C/cm2). Lattice matching appears for alloy composition between x = 0.81 and x = 0.82 when the piezoelectric polarization vanishes. The induced polarization varies from (−14×l0−6 C/cm2) to (10.85×l0−6 C/cm2). The calculated sheet carrier concentration is 6.3×l012, 1.73, 2.88 and 4.08×l013cm−2 for alloy compositions x = 0.75, 0.80, 0.85 and 0.90 respectively. Also barrier thickness on sheet carrier concentration is studied. [ABSTRACT FROM PUBLISHER]

The aim of this work is to study the potential offered by microwave power in the device AlmGa1−mN/GaN HEMT. The effects of technological and electrical parameters such as the aluminum mole fraction "m", the thickness of the AlGaN doped layer "dd" and doping concentration "Nd" in the output conductance are studied taking into account the effects of spontaneous and piezoelectric polarizations in the heterojunction AlGaN/GaN and the relaxation of the crystal lattice induced by the aluminum mole fraction. We presented an analytical model for the electrons concentration "ns" in the 2DEG and the current Ids in the channel for strong inversion regime by solving the Poisson equation and Schrödinger self-consistent calculations. From the analytical model of the current Ids including the effects of spontaneous and piezoelectric polarizations, and lattice relaxation, the output conductance gds according to the voltage Vds are deduced. We note that, the increasing of "m" and "Nd" increase the carrier density "ns" in the 2DEG. Although, the increase of the doped layer thickness increases the output conductance. The influence of the crystal lattice relaxation on the electrical performance acts directly on the threshold voltage if the value of the mole fraction exceeds 0.38. [ABSTRACT FROM PUBLISHER]