Accession Number:

ADA126792

Title:

FET (Field-Effect Transistor) Noise Studies.

Descriptive Note:

Final technical rept. Jun 81-Sep 82,

Corporate Author:

RAYTHEON CO LEXINGTON MA

Personal Author(s):

Report Date:

1982-10-01

Pagination or Media Count:

130.0

Abstract:

The GaAs FET oscillator is an alternative device for voltage-controlled oscillator VCO applications because of tis inherent wide-band electronic tunability, the variety of operating modes possible such as common source, common gate, etc., and the ease of circuit design. However, it has one major drawback, namely, its high near-carrier 1f noise which makes it unsuitable for many applications, such as radar systems. This report describes the progress made during the report period in understanding the relationship between fabrication technology and near-carrier oscillator noise of FETs. The IV characteristics, baseband noise, and near-carrier FM noise of GaAs FETs were measured for a variety of fabrication technologies. These included FETs were measured for a variety of fabrication technologies. These included fets with A1, CrAu, and TiPtAu gates, with SiOx,Si3N4, and polyimide passivations, with epitaxial and implanted channels, and with mesa and oxygen implant isolation. It was shown that bulk and surface traps were primarily responsible for the hysteresis of the IV characteristics, and the baseband and near-carrier 1f noise. The hysteresis vanished at high temperatures or under illumination of the FET surface with a GaA1As laser. The baseband noise increased with laser illumination.

Subject Categories:

  • Electrical and Electronic Equipment
  • Cybernetics
  • Solid State Physics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE