*** 9761508 Eisgruber This Small Business Innovative Research Phase I project proposes development of thin film copper indium diselenide (CIS) thermoelectric devices on rigid and flexible substrates, including both development of the film growth process for thermoelectrics and modeling the incorporation of the devices into systems with specific power generation or cooling requirements. Currently, high production costs and low efficiency inhibit the widespread use of thermoelectric devices. Most commercially available thermoelectric devices are manufactured using single crystal semiconductor stacks. Single crystal fabrication technologies are fairly mature; To reduce production costs, new materials and fabrication technologies must be utilized. Recent developments in deposition of CIS for use in thin film photovoltaic modules has been especially dramatic. Interestingly, CuInSe2 also holds great promise for thermoelectric devices. Initial investigation of its thermal properties indicate a very high (exceeding unity) thermoelectric figure of merit. The development of inexpensive, lightweight thermoelectric devices promises a huge commercial potential. Possible applications include electronics cooling, precisely controlled refrigeration for medical applications, power generation from vehicle exhaust heat recovery, and silent, compact air-conditioning for use in ships and submarines. Mobile applications stand to benefit significantly from the development of flexible thermoelectrics, as flexible substrates reduce both weight and packaging size. ***