Effect of the interface glass on electrical performance of screen printed Ag thick-film contacts of Si solar cells

Abstract

Glasses with compositions (40 - x)PbO - xZnO - 60(B2O 3 - SiO2) (x = 5, 10, 15, 20) have been prepared. Substitution of ZnO for PbO increased glass bandgap (Eg) and crystallization ability greatly. Crystalline phases of bulk glasses after rapid thermal processing (RTP) were identified by X-ray diffraction (XRD). Transmission line model (TLM) was employed to measure the electrical performance of Ag electrodes screen printed on polycrystalline Si substrates using Ag thick-film pastes and by RTP. The conductivity (σ) decreased while specific contact resistance (ρc) was not monotonic varied with increasing ZnO content. The correlation between electrical performance and glass barrier formed on the Ag gridline and Si emitter interface has been investigated. © 2010 Elsevier B.V.