Fabrication and Optimization of Brush-Printed n-type Bi^sub 2^Te^sub 3^ Thick Films for Thermoelectric Cooling Devices

• Published in: Journal of electronic materials 2016-03, Vol.45 (3), p.1328
• Main Authors: Liu, Xing, Zhao, Wen-yu, Zhou, Hong-yu, Mu, Xin, He, Dan-qi, Zhu, Wan-ting, Wei, Ping, Wu, Han, Zhang, Qing-jie
• Format: Article
• Language: English
• Subjects: Cooling; Electric properties; Optimization techniques; Thermodynamics; Thickness measurement
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-015-4027-7

Issue Title: 2015 International Conference on Thermoelectrics. Guest Editors: Jihui Yang, Matt Beekman, Donald Morelli, James Salvador, David Singh, Hsin Wang, Emmanuel Guilmeau, Juri Grin, Bertrand Lenoir, Xinfeng Tang, Wenqing Zhang, Chunlei Wan, TieJun Zhu, Ryoji Funahashi, Takao Mori, Tsunehiro Takeuchi, Sabah Bux A simple, efficient and rapid brush-printing method has been developed for preparation of n-type Bi^sub 2^Te^sub 2.7^Se^sub 0.3^ films approximately 100-150 [mu]m thick. X-ray diffraction, scanning electron microscopy, electron probe microanalysis, and four-point probe measurements were used to characterize the crystal structure, composition, microstructure, and electrical properties of the films. The results showed that all the n-type Bi^sub 2^Te^sub 2.7^Se^sub 0.3^ thick films were composed of single-phase Bi^sub 2^Te^sub 2.7^Se^sub 0.3^; the grains in the films were randomly distributed in the low-temperature-annealed samples and predominantly oriented along the (00l) plane in samples annealed at temperatures >673 K. σ and the absolute value of [alpha] first increased substantially with increasing the annealing temperature in the range 573-673 K then decreased when the annealing temperature was increased further. The dependence of σ and [alpha] on annealing temperature may be reasonably explained on the basis of the change in the microstructure induced by annealing. The performance of a prototype cooling device containing n-type Bi^sub 2^Te^sub 2.7^Se^sub 0.3^ thick films was evaluated for temperature differences produced by use of different DC currents.