High spatial resolution micro-Raman temperature measurements of nitride devices (FETs and light emitters)

✍ Scribed by Kuball, M. ;Pomeroy, J. W. ;Rajasingam, S. ;Sarua, A. ;Uren, M. J. ;Martin, T. ;Lell, A. ;Härle, V.

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 293 KB
• Volume: 202
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.200461294

✦ Synopsis

Abstract

Knowledge of the temperature in the active area of III‐nitride semiconductor devices such as AlGaN/GaN HFETs is essential for optimizing device design, performance and reliability, however, direct measurement of this temperature is not readily achieved. Infrared techniques often employed to measure the temperature of an active device are not well suited for AlGaN/GaN HFETs due to their limited spatial resolution when compared with the only micron‐size source‐drain device openings. The novel use of micro‐Raman spectroscopy for in‐situ measurements of device temperature, i.e., self‐heating effects, in single‐ and multi‐finger AlGaN/GaN HFETs with micrometer‐size resolution is discussed. Effects of device design on device temperature are illustrated. Variations in device temperature over a full wafer are studied considering that device reliability is strongly affected by device temperature. Applications of the technique to opto‐electronic devices in particular to InGaN/GaN laser diodes are also presented. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)