Extremely uniform threshold voltage distribution of GaAs FET made on LEC-grown crystals

Extremely uniform threshold voltage distribution of a GaAs FET with a standard deviation of 7 mV in a 20 mm × 20 mm area of In-doped low-dislocation-density LEC-grown substrates was obtained after excluding several extraordinary data points. The deviation of the threshold voltage at the extraordinary data points was as large as 100¿150 mV. No significant correlation of the extraordinary threshold voltage with distance of the gate to a nearest dislocation was observed.