Pulsed Measurements on Heterojunction Devices
Abstract
The goal of this project has been the characterization of impact-ionization effects in advanced microwave devices by means of pulsed techniques. Breakdown of GaAs-based MESFETs and HEMTs, and of InP-based HEMTs has been studied by means of 20 - 500 ns pulses generated by changed transmission lines (TLP, Transmission Line Pulse, technique). Results can be summarized as follows: (a) due to the non negligible influence of thermal effects on breakdown characteristics, and to the presence of unstable portions of I-V curves of the devices, TLP is the only technique which enables a realistic evaluation of on-state breakdown characteristics of power devices; (b) by measuring non-destructively the on-state breakdown curves up to gate current density levels never reached in the literature, we show that breakdown is triggered by a self-regenerative effect due to a parasitic bipolar action and is quenched by high injection and thermal effects occurring at high drain currents; (c) this analysis of on-state breakdown mechanisms is confirmed by Monte Carlo simulations. On the basis of the experimental observations, an equivalent circuit model of breakdown suitable for circuit SPICE-like simulations has been developed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2000
- Accession Number
- ADA378492
Entities
People
- Alessandro Chini
- Dario Buttari
- E. Zanoni
- Gaudenzio Meneghesso
- Massimo Maretto