Work

Mid-infrared photothermoelectric detector using topological insulator BiSb thin film

Year: 2025

Type: article

Abstract: We demonstrate a mid-infrared (MIR) photothermoelectric (PTE) detector based on a Bi 90 Sb 10 thin film, a topological insulator with strong MIR absorption and a high Seebeck coefficient. BiSb films were deposited by magnetron sputtering, a scalable and cost-effective method, on both sapphire and flexible Kapton substrates. The PTE response was systematically evaluated for various device geometries. A maximum voltage of 27 µV was obtained for a 16 mm × 0.25 mm × 80 nm film on sapphire. A 3 × 3 array of 4 mm × 0.25 mm elements was demonstrated. Finally, we demonstrated a large PTE response of 170 µV with improved detectivity D * of 1.1⋅10 5 cmHz/W for a BiSb-based PTE device on a Kapton flexible substrate. These results highlight the potential of sputtered BiSb thin films for large-area MIR detector arrays with low fabrication cost.

Source: Optical Materials Express

DOI: 10.1364/ome.571598

Authors: Hajime Nishiyama, Pham Nam Hai, Yukio Kawano

Institutions: Institute of Science Tokyo, Chuo University, National Institute of Informatics, Kanagawa Institute of Industrial Science and Technology

Language: English

Topic: Advanced Thermoelectric Materials and Devices

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: gold

Estimated APC paid: $1,843