Photovoltaic solar cells

摘要

The invention provides photovoltaic concentrator solar cells and a method of forming these from a semiconductor wafer. The method has the steps of first doping the rear surface of said wafer so as to provide a first doped region. Depositing passivation layers on the front and rear surfaces. Forming a deep groove in the rear surface through the passivation layer and doping said rear surface so as to provide an oppositely doped second doped region in the deep groove. Then an opening is formed through the rear passivation layer to the first doped region; and electrical contacts are formed on the rear surface to electrically connect to the first and second doped regions.;The photovoltaic concentrator solar cell has a semiconductor wafer with a passivation layer deposited on front and rear surfaces; and a first doped region at the rear surface. It also has a p-type contact in an opening from the rear surface to contact with said first doped region; an n-type electrical contact in a deep groove extending into the wafer from the rear surface; and a second doped region, doped from with the groove after formation thereof but prior to formation of the n-type electrical contact.

主权项

1. A method of forming photovoltaic concentrator solar cells from a semiconductor wafer having a front surface and a rear surface comprising the following steps:
(a) doping the rear surface of said wafer so as to provide a first doped region at the rear of said wafer; (b) depositing passivation layers on the front and rear surface to provide a dopant mask; (c) forming a deep groove in the rear surface through the passivation layer, to within one diffusion length of the front surface of the wafer; (d) doping said rear surface so as to provide a second doped region solely in the deep groove, said second doped region being oppositely doped to said first doped region, the passivation layers acting as a mask to confine diffusion into the wafer to the deep groove only; (e) forming an opening, through the rear passivation layer to the first doped region; and (f) forming electrical contacts on said rear surface to electrically connect to the first and second doped regions.