Title :
Investigation of laser ablation of silicon nitride passivation with self-doping paste for solar cell contacts
Author :
Payne, Adam M. ; Rapolu, Kalyan ; Davis, Preston ; Chandrasekaran, Vinodh ; Meier, Daniel ; Xu, Baomin ; Zesch, Jim ; Littau, Karl
Author_Institution :
Suniva, Inc., Norcross, GA, USA
Abstract :
We have fabricated solar cells using a standard POCl3 process along with a PECVD SiNx AR coating. In particular, we have also used a self-doping paste with belt furnace firing in conjunction with laser ablation to remove the silicon nitride passivating layer to minimize the metal contact area. Use of laser ablation to create holes in the nitride passivation is coupled with use of a silver self-doping paste to create a selective emitter. Cell results with an efficiency of 13% were obtained. Discussion of the fabrication steps needed and the analysis of the data are given below. The cells suffer from low open circuit voltage as well as modest fill factors. Increased shading losses and unoptimized AR coating limit Jsc. The self-doping paste cells had a very high contact resistance, the root causes of which are discussed.
Keywords :
antireflection coatings; contact resistance; doping; laser ablation; plasma CVD coatings; silicon compounds; solar cells; PECVD AR coating; POCI3; SiNx; belt furnace; contact resistance; fill factor; laser ablation; metal contact; open circuit voltage; selective emitter; shading loss; silicon nitride passivation; silver self-doping paste; solar cell contact; solar cell fabrication; Contact resistance; Hafnium; Laser ablation; Resistance; Silicon; Silver; Surface emitting lasers;
Conference_Titel :
Photovoltaic Specialists Conference (PVSC), 2010 35th IEEE
Conference_Location :
Honolulu, HI
Print_ISBN :
978-1-4244-5890-5
DOI :
10.1109/PVSC.2010.5614357