STRAIN-SYMMETRIZED INXGA1-XAS/INYAL1-YAS HEMTS WITH EXTREMELY HIGH 2DEG DENSITIES AND MOBILITIES

Strain-symmetrized InxGa1-xAs/InyAl1-yAs heterostructures with 0.53 less than or equal to x less than or equal to 0.74 and 0.52 greater than or equal to y greater than or equal to 0.415 and enhanced 2DEG densities and mobilities were grown by molecular beam epitaxy on InP substrates. The increased conduction band offset resulted in extremely high electron densities of 3.81 x 10(12) cm(-2), with a 4.2 K mobility of 51100 cm(2)/Vs for single-sided doping and highest ever densities of 6.70 x 10(12) cm(-2) for double-sided doping. The strain-symmetrization with stress compensating InyAl1-yAs barriers did not, however, allow an increase in the critical In content of the InxGa1-xAs QW.