A thin film thermoelectric generator that consisted of 5 p/n pairs was fabricated with 1 μm-thick n-type In3Sb1Te2 and p-type Ge2Sb2Te5 deposited via radio frequency magnetron sputtering. First, 1 μm-thick GST and IST thin films were deposited at 250 oC and room temperature, respectively, via radio-frequency sputtering; these films were annealed from 250 to 450 oC via rapid thermal annealing. The optimal power factor was found at an annealing temperature of 400 oC for 10 min. To demonstrate thermoelectric generation, we measured the output voltage and estimated the maximum power of the n-IST/ p-GST generator by imposing a temperature difference between the hot and cold junctions. The maximum output voltage and the estimated maximum power of the 1 μm-thick n-IST/p-GST TE generators are approximately 17.1 mV and 5.1 nW at ΔT = 12K, respectively.

The electro-deposition of compound semiconductors has been attracting more attention because of its ability torapidly deposit nanostructured materials and thin films with controlled morphology, dimensions, and crystallinity in a cost-effective manner (1). In particular, low band-gap A2B3-type chalcogenides, such as Sb2Te3 and Bi2Te3, have been extensivelystudied because of their potential applications in thermoelectric power generator and cooler and phase change memory.Thermoelectric SbxTey films were potentiostatically electrodeposited in aqueous nitric acid electrolyte solutions containingdifferent ratios of TeO2 to Sb2O3. The stoichiometric SbxTey films were obtained at an applied voltage of −0.15V vs. SCE usinga solution consisting of 2.4mM TeO2, 0.8mM Sb2O3, 33mM tartaric acid, and 1M HNO3. The stoichiometric SbxTey filmshad the rhombohedral structure with a preferred orientation along the [015] direction. The films featured hole concentrationand mobility of 5.8×1018/cm3 and 54.8cm2/V·s, respectively. More negative applied potential yielded more Sb content in thedeposited SbxTey films. In addition, the hole concentration and mobility decreased with more negative deposition potential andfinally showed insulating property, possibly due to more defect formation. The Seebeck coefficient of as-deposited Sb2Te3 thinfilm deposited at −0.15V vs. SCE at room temperature was approximately 118µV/K at room temperature, which is similarto bulk counterparts.