Accession Number:

ADA255233

Title:

Physics and Technology of Resonant-Tunneling Devices

Descriptive Note:

Final rept. 1 May 1989-30 Apr 1992

Corporate Author:

MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB

Personal Author(s):

Report Date:

1992-07-01

Pagination or Media Count:

200.0

Abstract:

Over the three-year course of this program, several issues in the device physics of resonant-tunneling diodes RTDs have been investigated, including the small-signal admittance, the shot noise, and the transport through multiple-quantum well structures. A large quantum-well inductance has been measured in the negative-differential-resistance region NDR, but not in the positive-differential-resistance PDR region. The microwave shot-noise has been found to be suppressed relative to normal shot-noise in the PDR region, but enhanced in the NDR region. Triple-well RTDs have displayed a much wider NDR region in voltage than conventional single-well RTDs. Several new RTD material systems have been demonstrated including Type-II InASAlSb and Type-I GaSbAlSb, the first of which has yielded excellent properties for high-speed device applications. Studies of highly lattice mismatched InAsAlSb RTDs on GaAs substrates have proven that the RTD characteristics are insensitive to a high density of dislocations. Finally, these results have been incorporated into the design of RTDs in high-frequency oscillators and high-speed switches. The InGaAsAlAs RTD has been optimized for application in a quasioptical fundamental-frequency oscillator operating above 200 GHz. The same material system has been used to make a low-power RTD load for heterojunction field- effect and bipolar transistors in high-performance digital integrated circuits.

Subject Categories:

  • Electricity and Magnetism

Distribution Statement:

APPROVED FOR PUBLIC RELEASE