Innovative Circuits in Emerging Technologies – ISSCC2012
February 22, 2012, ISSCC, San Francisco—Emerging technologies provide a window into areas that are far from the beaten track, but have the potential to be important at some time in the future.
Energy harvesting can enable the addition of electronics to many new applications. The University of Tokyo developed a self powered, insole pedometer. The piezoelectric energy harvester is also the substrate for the organic, PMOS devices. The substrate is made of 21 layers of polyvinylidene difluoride which generates about 2 V. This voltage is used to run the circuits for counting steps.
Continuing with organic devices, Katholic University of Leuven is working on organic, capacitive touch sensors on a plastic foil. This film will be combined with flexible displays to make a flexible touch screen, or a control input for other functions. The substrate choice forces the use of organic transistors are compatible with the low temperature processing of the plastic material. The problem with organic transistors is that are very low speed and power capabilities.
Another transistor technology is amorphous gallium indium zinc oxide. Thin-film transistors using this material have achieved better electron mobility than amorphous silicon. The optical transparency and relatively low processing temperatures make this technology compatible with any larger applications on plastic foils. A demonstration circuit from Eindhoven University of Technology is a six bit 10 mega-sample per second digital to analog converter.
At the other extreme and performance, UCLA showed a self compensating 60 GHz transceiver. One challenge of working in millimeter wave technologies is the parametric drift and the need for transmitter and receiver retuning over the life of the transceiver. This system monitors key parameters and makes adjustments to retune and optimize both the transmit and receive chains.
Mechanical components are now moving down to the nanometer range, making NEMS (nano electro-mechanical systems) compatible with CMOS processing. The reduced size of the mechanical components enables greater sensitivity and very dense arrays of sensors. CEA-LETI presented a single crystal NEMS resonator and its CMOS electronics on a single chip.