Chipsensors, a fabless semiconductor start-up company, has unveiled what it describes as a breakthrough in semiconductor technology that enables the surface of the chip itself to sense parameters such as temperature, humidity, certain gases and pathogens.
The patent-pending technology exploits the fact that the dielectric material in standard sub-micron CMOS comprises porous oxides and polymers; by selectively admitting or blocking ingress of the agent to be sensed, any resulting changes in electrical characteristics can be accurately detected and measured.
The sensor technology is being shown in public for the first time at the RFID Europe 2007 exhibition in Cambridge. Visitors to booth 17 will be able to see a working demonstration of a prototype single-chip temperature and humidity sensor, communicating via an off-chip wireless link to a laptop PC displaying real-time measurements.
The 0.13um sensor chip being shown has obvious applications as an all-electronic replacement for the type of electromechanical thermostats and humidistats used in building management and environmental monitoring systems. Chipsensors is also developing an ultra-low-power wireless version of this sensor for incorporation into passive and active ID tags; this version integrates all the signal conditioning, microcontroller, memory and RF transceiver functions onto the same chip as the sensor.
Until now, most sensors have been manufactured on glass or ceramic substrates, using specialist materials and manufacturing processes, and have proved difficult to accommodate within mainstream foundry CMOS processes. The wafers had to be post-processed and the sensors then required testing and calibrating after packaging, which was time-consuming and expensive. Chipsensors' proprietary technology is said to overcome these obstacles. It enables sensors, signal conditioning circuits - including high-resolution analogue-to-digital converters - and RF transceiver functions, together with the microcontroller and memory, to be integrated on a single chip, fabricated entirely from standard CMOS.
Chipsensors Ltd was founded in 2006 as a spin-out from a design consultancy that specialises in wireless sensors. Initially self-funded, with matching grants and equity from various government agencies, the company attracted sufficient venture capital to seed development of its innovative silicon sensors. Chipsensors is now on the verge of commercialising this technology, and is currently engaged in negotiations with international customers, partners and potential investors.
Tim Cummins, Chipsensors' CEO, states: "By 'piggy-backing' on mainstream semiconductor technology developments in this manner, we are 'putting sensors on Moore's Law', opening the door to true low-cost and high-volume scalability for wireless sensors."