Bulk hydrogeneration in mc-Si by PECVD SiNx deposition using direct and remote plasma

conference paper
Our investigation focuses on the effect of bulk hydrogenation in mc-Si via PECVD SiNx deposition at low temperatures, so without a subsequent firing step. In a recent publication we have shown that bulk lifetime improvement in mc-Si takes place during PECVD SiNx deposition at 450??C in a PECVD furnace with direct plasma and low plasma generator frequency. In this work we study the bulk hydrogenation of mc-Si during SiNx deposition in different PECVD systems with direct and remote plasma. Tests were performed on p-type and n-type wafers from mc-Si ingots, p-type String Ribbon wafers and p-type EFG ribbon wafers. Neighbouring and adjacent wafers respectively are used to compare bulk lifetimes after single and double sided SiNx deposition on wafers as grown and after P-gettering. Bulk lifetime was measured spatially resolved with ?ѭPCD. Surface passivation was provided with an iodine-ethanol solution. Significant bulk lifetime improvement in mc-Si takes place during SiNx deposition at low temperatures in PECVD systems with direct and remote plasma, without additional firing step. The effect varies for different mc-Si materials, however, a general statement for all mc-Si materials is difficult.
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TNO Identifier
821502
Publisher
ECN
Source title
23rd European Photovoltaic Solar Energy Conference and Exhibition, Valencia, Spain, 1-5 september 2008.
Collation
4 p.
Place of publication
Petten
Pages
4 p.