STUDY ON EFFECT OF SUBSTRATE TEMPERATURE ON TUNGSTEN OXIDE FILMS BY HOT-WIRE CVD DEPOSITION

Zhang Xu; Guo Cong; Chen Tao; Yu Jian; Tang Shuihua

doi:10.19912/j.0254-0096.tynxb.2023-1770

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Acta Energiae Solaris Sinica ›› 2025, Vol. 46 ›› Issue (3) : 335-341. DOI: 10.19912/j.0254-0096.tynxb.2023-1770

STUDY ON EFFECT OF SUBSTRATE TEMPERATURE ON TUNGSTEN OXIDE FILMS BY HOT-WIRE CVD DEPOSITION

Zhang Xu, Guo Cong, Chen Tao, Yu Jian, Tang Shuihua

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Abstract

Tungsten oxide （WO_x） thin films were prepared via hot-wire chemical vapor deposition and applied to dopant-free silicon heterojunction solar cells. It was found that substrate temperature played a crucial role during the deposition process. As the substrate temperature increased from room temperature to 200 ℃, the surface particle size of the WO_x thin film decreased, and the film became denser. The work function first increased and then rapidly decreased. The transmittance showed no significant change when the temperature lower than 150 ℃, but rapidly decreased as the further increased temperature. By replacing the p-type amorphous silicon layer, it was applied to dopant-free silicon heterojunction solar cells as a hole-selective contact layer. Under the condition of a substrate temperature of 100 ℃, the highest conversion efficiency of 14.63% was achieved at the substrate temperature of 100 ℃. This work demonstrated the feasibility and great potential of preparing WO_x by hot-wire chemical vapor deposition for high-efficiency dopant-free silicon heterojunction solar cells.

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crystalline silicon solar cells / tungsten compounds / thin films / chemical vapor deposition / temperature / substrate

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Zhang Xu, Guo Cong, Chen Tao, Yu Jian, Tang Shuihua. STUDY ON EFFECT OF SUBSTRATE TEMPERATURE ON TUNGSTEN OXIDE FILMS BY HOT-WIRE CVD DEPOSITION[J]. Acta Energiae Solaris Sinica. 2025, 46(3): 335-341 https://doi.org/10.19912/j.0254-0096.tynxb.2023-1770

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