Cold Spray Deposition of Copper Electrodes on Silicon and Glass Substrates

Abstract

Copper lines with widths varying from 150 to 1500 mu m were deposited onto crystalline silicon wafers and soda-lime glass plates by cold spraying copper particles with 1 mu m average diameter through a mask. This direct deposition method yielded high-aspect-ratio electrodes with minimum shadowing effects and maximum electrode-to-silicon contact area. The copper lines had triangular cross sections with aspect ratios (height/width) ranging from 0.1 to 1.1, depending on the number of spray gun passes. Copper particles were densely packed with increasing the width of the masking slit. This study presents the potential use of the cold spray technology in printing lines as front electrodes in solar cell applications.