Physics and Technology of Resonant-Tunneling Devices
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 InAS/AlSb and Type-I GaSb/AlSb, the first of which has yielded excellent properties for high-speed device applications. Studies of highly lattice mismatched InAs/AlSb 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 InGaAs/AlAs 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.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1992
- Accession Number
- ADA255233
Entities
People
- E. R. Brown
Organizations
- Massachusetts Institute of Technology