Raman-IR micro-thermography tool for reliability and failure analysis of electronic devices

We report on the development of a integrated Raman - IR thermography technique to probe self-heating in active devices. We compare and discuss advantages of both techniques in terms of spatial resolution on the example of AlGaN/GaN HFET devices. While traditional infra-red (IR) thermography can provide fast overviews of self-heating in the devices over large scales, its use for extraction of channel temperatures is limited by the sub-micron size of the active area in modern devices. Integration with micro-Raman thermography provides not only improvement in spatial resolution down to 0.5 mum on the surface but also unprecedented micron scale depth resolution for true 3D thermography. This enables unique thermal analysis of semiconductor devices on a detailed level not possible before. As it is a generic technique its application can be extended to Si, GaAs and other devices. This opens new opportunities for device performance and reliability optimization, and failure analysis in research and development of modern semiconductor technology, as well as for quality control/ manufacturing environments.