A Study on Sputtered Bi-Te Thermoelectric Films with Various Compositions: Microstructure Evolution and the Effects on Thermoelectric and Electrical Properties

作者：Oh Minsub^*; Jeon Seong Jae; Jeon Haseok; Hyun Seungmin; Lee Hoo Jeong

来源：Journal of Electronic Materials, 2012, 41(1): 60-66.

DOI：10.1007/s11664-011-1751-5

• Phase transformation
• Bi-Te thin film
• thermoelectric materials
• postannealing
• Te composition

This study examined the sensitive effects of composition on the microstructure evolution and thermoelectric properties of sputtered Bi-Te films. Bi-Te films of various Te compositions (49 at.% to 60 at.%) were grown by cosputtering deposition and annealed at 200A degrees C for different durations. We examined the microstructure of the films using x-ray diffraction (XRD) and transmission electron microscopy (TEM), and measured the electronic transport and thermoelectric properties. As the Te composition of the films changed from 49 at.% to 60 at.%, the phase of the as-sputtered film changed from the rhombohedral BiTe-type phase to the metastable rock-salt phase, which eventually transformed to the Bi2Te3-type phase upon annealing, instigating microstructure evolution. This phase transformation profoundly influenced the electrical and thermoelectric properties of the films.

• 出版日期2012-1