Improved thermoelectric performance of flexible p-type SiGe films by B-doped Al-induced layer exchange. (12th December 2019)

• Record Type: Journal Article
• Authors: Tsuji, M; Imajo, T; Saitoh, N; Yoshizawa, N; Suemasu, T; Toko, K
• Is Part Of: Journal of physics. Volume 53:Number 7(2020)
• Publication Date: 2019-12-12
• Subjects: SiGe-on-insulator -- Al-induced layer exchange -- polycrystalline film -- impurity doping -- thermoelectrics; Physics -- Periodicals; 530
• DOI: 10.1088/1361-6463/ab5989
• Languages: English
• ISSNs: 0022-3727

Abstract

Abstract: The Al-induced layer exchange is a useful method for the low-temperature synthesis of high-performance SiGe thermoelectric thin films. Because B has a high solid solubility in SiGe, we examined the self-organized doping of B to SiGe during layer exchange to further improve p-type thermoelectric properties. The hole concentration and the electrical conductivity were improved in the whole SiGe composition range when an appropriate amount (~1%) of B to Al was added. A Si0.4 Ge0.6 layer fabricated on a polyimide substrate at 350 °C exhibited a power factor of 240 µ W m −1 K −2, which is best recorded as environmentally-friendly inorganic semiconductors formed on flexible substrates. The low-temperature Fermi-level-control technology for semiconductor films will exploit various flexible devices including thin-film thermoelectrics.