Thermoelectric properties of single-layer MoS₂ and WSe₂
Tang-Yu Lin1,3*, Pai-Chun Wei1, Kuan-Chang Chiu2, Yi-Hsien Lee2, Yung-Kang Kuo3, Yang-Yuan Chen1
1Institute of Physics, Academia Sinica, Taipei, Taiwan
2Department of Materials Science and Engineering, National Tsing-Hua University, Hsinchu City, Taiwan
3Department of Physics, National Dong Hwa University, Hualien, Taiwan
* presenting author:林塘御,
Molybdenum disulfide (MoS₂) and tungsten diselenide (WSe₂) are prototypical layered two-dimensional transition metal dichalcogenide (TMD) materials, with each layer consisting of three atomic planes. We refer to each layer as a trilayer (TL). Recent theoretical calculation has suggested that the room-temperature ZT can reach 1.6 and 2.1 for n-type 1TL-MoS₂ and 2TL-WSe₂, respectively. However, the fabrication of single-layer TMD devices is still suffering from the poor metal contact with electrodes, i.e., large contact resistance at metal/semiconductor interface still remain a challenge. In this presentation, we study the metal/semiconductor contact resistance by changing contact metal, metal deposition rate, contact geometry and contact area. With the success of micro-device fabrication, we investigate the thermoelectric properties of electrical conductivities and Seebeck coefficients on the CVD-grown single-layer MoS₂ and WSe₂ specimens.

Keywords: Transition metal dichalcogenide, Thermoelectric properties