Realization of TOPCon using industrial scale PECVD equipment
This paper discusses the successful realization of tunnel oxide passivated contacts (TOPCon) using industry-relevant PECVD equipment. It will be shown that batch-type direct plasma PECVD allows for a damage-free deposition of doped a-Si onto an ultra-thin oxide layer. Using symmetric test structures the impact of thermally or wet-chemically grown ultra-thin interfacial SiOx layer, as well as the influence of the poly-Si doping level on the surface passivation quality will be discussed in detail. Maximum values of 736 mV iVoc and 87.4 % iFF were achieved. Additionally, asymmetric lifetime samples featuring an n-type TOPCon at the rear and a p-type TOPCon at the front demonstrated 720 mV Voc.
Glunz, Stefan W.