Technical Problem and Solution

Harsh environments are originally characterized by extreme operation under one or several of the following stress conditions : mechanical, thermal or chemical. More and more, an additional characteristic of such environments can become their remote or difficult-to-access location. Harsh environment microsystems thus become very complex systems which combine arrays of diverse sensors with high-performance electronics including sensor interface, analog and digital signal processing, memory and communication (possibly wireless) circuits. Powering such complex devices further becomes an ever more important issue, calling for low-power implementations and / or energy scavenging from the environment itself, to reduce the battery problem. Extreme conditions are then to be defined according to the resistance of electronics systems to such constraints, which depends on two aspects : packaging and semiconductor. Semiconductor intrinsic resistance to harsh environment conditions is related to the degradation of the characteristics of transistors with temperature elevation. Most conventional electronics fail above 125-175°C. Out of several contenders (including wide-bandgap materials), only one technology has proved capable to produce the required complex integrated circuits correctly operating at temperatures up to at least 300°C, namely Silicon-on-Insulator or SOI. Furthermore, SOI also positions as a generic platform for many MEMS and sensors implementation with functionalities and performance of interest for the aerospace applications targeted here : pressure transducers, accelerometers, flame detectors, magnetometers, gas composition and flow sensors, temperature and humidity sensors.
Over the years, thin SOI technology has enabled the design and realization of environmental sensors such as thin-film temperature, humidity , optical (UV or IR specific), and magnetic sensors, as well as physical/chemical sensors such as thin-membrane based sensors (micro-hot plate, flow, gas…), all with excellent performance. These are mainly based on the integration of original surface and bulk micromachining steps within the SOI CMOS process flow (which is dramatically eased thanks to the unique ‘thin silicon film over buried oxide’ SOI structure).
Assuming that technical problems can be solved in principle, the remaining question is who will produce the devices and what will be an associated cost. Since the Harsh Environment (HE) market is small in comparison to the major markets of the IC foundries, it is very unlikely that HE customers will get an access to those foundries for the reasonably cost. The solution which is proposed in this Project is to create the dedicated foundry to lay a base for the viable source of HE MNT and associated electronic circuits.