Achieving low contact resistivity in PEDOT:PSS/n-Si solar cells

Good conductivity and transparency in the visible spectrum along with low processing temperatures and ease of fabrication make Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) a widely accepted polymer for organic-inorganic hybrid heterojunction solar cells. Although the overall conductivity of the PEDOT:PSS is high, the PSS segregates more at the surfaces of the deposited film. This leads to high contact resistivity of PEDOT:PSS film with metal and silicon. In this report, we explore the effect of the spin coating rates on the contact resistivity of PEDOT:PSS with the metal and silicon and the associated performance of PEDOT:PSS/n-Si solar cells. Two different spin speeds of 1000 rpm and 4000 rpm were used to deposit the PEDOT:PSS films over silicon. The PEDOT:PSS films were also deposited in single- and double-layer forms. We could achieve very low contact resistivity of PEDOT:PSS with silicon through spin speed optimizations. Hence, the overall performance of the PEDOT:PSS/n-Si solar cells improves with the spin speed for both single- and double-layer PEDOT:PSS film depositions.

Automated summary

Good conductivity and transparency in the visible spectrum, along with low processing temperatures and ease of fabrication, make Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) a widely accepted polymer for organic-inorganic hybrid heterojunction solar cells. However, the PSS segregates more at the surfaces of the deposited film, leading to high contact resistivity with metal and silicon. In this report, we explore the effect of spin coating rates on the contact resistivity and performance of PEDOT:PSS/n-Si solar cells, achieving low contact resistivity and improved overall performance with optimized spin speeds.