New MBE buffer used to eliminate backgating in GaAs MESFETs

摘要

The buffer is grown by molecular beam epitaxy (MBE) at low substrate temperatures (150-300 degrees C) using Ga and As/sub 4/ beam fluxes. It is highly resistive, optically inactive, and crystalline, and high-quality GaAs active layers can be grown on top of the buffer. MESFETs fabricated in active layers grown on top of this new buffer show improved output resistance and breakdown voltages; the DC and RF characteristics are otherwise comparable to MESFETs fabricated by alternative means and with other buffer layers.