2.1.  The experience in high-temperature electronics.

The harsh environment domain can be more clearly defined and focused by gaining from the long experience in the high-temperature electronics field.

In the past, the high-temperature range of operation was most commonly defined starting at 125°C above which conventional circuits generally fail. But with the rapid obsolesence of 125°C-rated military semiconductor technologies, we may now expect high-temperature definition to start lower. Historically the development of large- or wide-bandgap semiconductors was first pursued: gallium arsenide (GaAs), III-V materials (In, P, GaN), silicon carbide (SiC), diamond. Although SiC or diamond semiconductors have the potential to operate well above 500°C, they are still not mature for short-term and large-scale exploitation; whereas GaAs, although well established and theoretically looking much more favourable than Si for use at elevated temperatures, has been clearly outperformed by CMOS on SOI (Silicon-on-Insulator) in terms of stability of device and circuit operation with temperature, simplicity and cost of process and of circuit design, integration of complex mixed analog-digital systems… Based on extensive device and circuit investigations, we have indeed seen that when considering fairly complex circuits (e.g. more than dozens of thousands gates), the technology of choice limits to SOI.

For driver for such developments is clearly the automotive sector, in which the interest for high-temperature electronics, wireless communication and embedded sensors is steadily growing. This was recently confirmed by several announcements of major companies, namely Delphi and GM.