Thermal infrared sensors for accurate motion detection
Continuing progress in processing technologies has stimulated the rapid development of integrated micro-sensors, in particular intelligent sensors with the same technology as integrated circuits (ICs). Importantly, implementing sensors in standard Complementary Metal-Oxide Semiconductor (CMOS) technology can ensure competitive prices by exploiting the strong manufacturing base of IC technologies, already perfected in low cost mass production. The TECH TIR project, funded under the Fifth Framework Programme, sought to address their lower sensitivity when compared to sensors implemented in specialised sensor technologies. Research conducted in the Elkron laboratories demonstrated the possibility of making up for the performance loss by co-integrating interface electronics, often rendering the design of the latter a challenging task. CMOS as a thermo-electrical infrared radiation sensor has the advantage of linear self-generated response without requiring bias or temperature stabilisation. The thermal infrared array sensor could thus be integrated on a single chip providing for amplifiers and signal processing capabilities. Such an approach allows rapid progression towards miniaturisation of thermal infrared sensors, without any loss of efficiency due to electromagnetic noise. Moreover, CMOS could be operated at very low voltage levels and still present good functionality, since it requires only limited amounts of energy. The highly sensitive sensor interface for CMOS compatible thermo-electrical infrared radiation sensors designed and manufactured within the TECH TIR project opens up interesting possibilities for motion detection applications. This same approach could be tailored for different ranges of wavelength and further applications areas.
