New MBE Buffer For Micron And Quarter-Micron Gate GaAs MESFET's

摘要

A new buffer layer has been developed that eliminates backgating in GaAs MESFET's and substantially reduces short-channel effects in GaAs MESFET's with 0.27-/spl mu/m-long gates. The new buffer is grown by molecular beam epitaxy at a substrate temperature of 200/spl deg/C using Ga and As/sub 4/ beam fluxes. The buffer is crystalline, highly resistive, optically inactive, and can be overgrown with high quality GaAs. GaAs MESFET's with a gate length of 0.27 /spl mu/m that incorporate the new buffer show improved dc and RF properties in comparison with a similar MESFET with a thin undoped GaAs buffer.