Development of a Remote Cutoff MOS Field Effect Transistor

摘要

The purpose of this program is to develop an advanced MOS field effect transistor having a tailored remote cutoff characteristic for decreasing cross modulation distortion and to provide improved AGC for communications receivers. The devices developed under this program are to be optimized for two frequency ranges: 14 KC to 30 MC and 200 MC to 400 MC. The stepped oxide remote cutoff MOS is superior to the ordinary triode MOS for low cross-modulation distortion. The triode MOS is poor in the high attenuation region of the automatic gain control (AGC) characteristics. In this region, the device is operated near cutoff. Initial samples of a continuously tapered oxide instead of stepped oxide have been tested and show promise. For the low frequency device, an investigation has been launched into the 1/F noise characteristics of the MOS. Measurements of noise resistance and noise currents are in progress. There appears to be a wide variation in 1/F noise characteristics in MOS transistors. (Author)