Structures for Thermal Stress Reduction in GaAs Layers Grown on Si Substrate

Abstract
The structures to reduce the thermal stress in GaAs grown on Si substrates produced by the thermal expansion coefficient mismatch are proposed and analyzed by the finite-element method. It was shown that the stress can be below 1/10 of the stress in the planar GaAs on Si by partially separating the GaAs layer from the substrate. The preliminary experimental results show that this technique reduces the stress to 1/10 of the normal stress in the area of as wide as 200×250 µm2.