IMPROVED PERFORMANCE OF A FIELD-EFFECT TRANSISTOR

In GaAs or Si FETs, the mobility of charge carriers in the channel is influenced by the electric field. The real velocity profiles of the carriers in the channel limits the transfer time. In order to improve the velocity of carriers we suggest: i) Create a doping gradient in the channel. ii) Use a series of independent gates each having a different DC bias. The Si multigate and GaAs dual-gate were fabricated. Measurements revealed that transconductance increased from 19.5 mS/mm to 30.5 mS/mm for the Si Device, and increased from 480 mS/mm to 640 mS/mm for the GaAs Device. © 1990.