Hydrosilane-Free Low-Cost APCVD of SiO2 Films for Crystalline Si Solar Cell Applications

A SiH4-free atmospheric pressure chemical vapor deposition (APCVD) technique was developed that provides a simple, flexible and cost-effective approach for the preparation of SiO2 coatings at room temperature. Microscopic investigations revealed that the deposited films are smooth and dense. No pinholes in the SiO2 coatings or gaps between the SiO2 and the substrate were found. On 6 inch Si wafers, the obtained SiO2 thickness variation was ± 10 %. After densification at 400 °C for a few minutes the layers are well suited for protective coatings in various applications. We successfully demonstrated i) single-side texturing of monocrystalline Si wafers and ii) elimination of parasitic metal deposition during electroplating of crystalline Si solar cells’ front side metallization.