Reliability of metamorphic HEMTs on GaAs substrates

• Published in: Microelectronics and reliability Vol. 42; no. 7; pp. 997 - 1002
• Main Authors: Marsh, P.F, Whelan, C.S, Hoke, W.E, Leoni III, R.E, Kazior, T.E
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.07.2002
• ISSN: 0026-2714; 1872-941X
• DOI: 10.1016/S0026-2714(02)00063-X

Metamorphic HEMT (MHEMT) technology enables the growth of high indium content channels on GaAs substrates, giving them the performance of InP HEMTs. MHEMT growth techniques use a graded alloy composition buffer layer structure, permitting channel indium contents exceeding 25% without strain. Potential applications include 40 Gb/s fiber optic receivers as well as LNAs for local multipoint distribution systems and satellite communications. Many such applications place stringent requirements on reliability with Belcore standards requiring 10 6 h median time to failure (MTTF) at 125 °C for power devices. Satellite applications require a LNA projected failure-free service of 15–30 years, implying approximately 10 7 h MTTF, at 85 °C. Naturally, one will ask “Is MHEMT technology reliable?” From the results of our ongoing work, we show that MHEMT reliability is similar to that of InP HEMTs with ∼10 6 h MTTF at 125 °C.