Technology overview

Even today, over four decades after it was first mooted, Moore’s Law pretty much holds true: the number of transistors on semiconductor ICs doubles every 24 months. Ever higher levels of functional integration are routinely achieved by the semiconductor manufacturing industry. The user advantages are both economic and technical: smaller, higher functionality chips reduce unit costs and time-to-market, and generally result in improved performance and lower power consumption, due to shorter interconnects and reduced parasitic capacitance.  The introduction of Copper and Low-K dielectrics to Deep-Sub-Micron CMOS (to make chips go faster and reduce power) is a recent example of the huge investments the semiconductor industry routinely makes to keep on track with Moore's Law.

Sensors, on the other hand, have historically been manufactured on glass or ceramic substrates, using specialist materials and manufacturing processes.  While much has been written about integration of sensors with CMOS, and indeed some products have begun appearing on the market, very few of these have scaled up to mass-market volumes or applications.   This is because they employ different types of fabrication materials, which are difficult to accommodate within mainstream foundry CMOS processes.  Wafers have to be "post-processed", and the sensors therefore have to be tested and calibrated after packaging, leading to a slow and expensive manufacturing solution, not amenable to the high-volume and low-cost requirements of the emerging wireless sensor market.

ChipSensors’ proprietary, patent-pending technology overcomes these obstacles. It enables all the sensors, signal conditioning circuits – including high resolution analog-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.   The Low-K dielectrics in Deep Submicron CMOS  (mentioned above) are actually porous oxides and polymers - which is what sensors have been using for decades.  The ChipSensors 'Eureka' breakthrough is to re-use these porous oxides and polymers for a purpose never intended - as sensors - and place 18-bit A-to-D converters on the very same chip underneath the sensors.  This enables sensing of tiny changes of conductivity and/or dielectric-constant in response to humidity and various gases, which we selectively admit or block, according to our patent-pending design and layout techniques.

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 scalebality for wireless sensors.