Solar cell and process of manufacturing the same
AssigneeImec Vzw
InventorsEmmanuel Van Kerschaver, Jozef Szlufcik, Roland Einhaus, Johan Nijs
Life of this patent
Estimating the term…
Abstract
The solar cell in the semiconductor substrate includes at least a radiation receiving front surface and a second surface. The substrate includes a first region of one type of conductivity and a second region of the opposite conductivity type with at least a first part located adjacent to the front surface and a second part located adjacent to the second surface. The front surface includes conductive contacts to the second region and the second surface has separated contacts to the first region and to the second region. The contacts to the second region at the second surface are connected to the contacts at the front surface through a limited number of vias.
Claims21
A solar cell comprising:
- a semiconductor substrate of a material wherein the diffusion length of minority carriers is lower than at least one of the dimensions of the substrate, said substrate comprising at least a radiation receiving front surface and a second surface, said substrate comprising a first region of one type conductivity, and a second region of the opposite conductivity type with at least a first part of said second region located over at least a part of the front surface and with at least a second part of said second region located over at least a part of the second surface, said front surface having conductive contacts to said second region and said second surface having separated contacts to said first region and to said second part of said second region wherein said second part of said second region is extending adjacent to the second surface beyond the contact area of the contacts to said second part of said second region and wherein the contacts to said second region at the second surface are connected to the contacts at the front surface through a limited number of vias.
A process for preparing a solar cell in a semiconductor substrate of a material wherein the diffusion length of minority carriers is lower than at least one of the dimensions of the substrate, said substrate having a first region of one conductivity type and a second region of the opposite conductivity type, said substrate being defined by a first surface intended to receive radiation and a second surface intended to receive contacts to the first region and the second region, said process comprising:
- machining a number of vias through the substrate;
- chemically etching said vias;
- introducing a dopand in the substrate including the walls of the vias and further extending over at least a part of said first surface and said second surface in order to create a second region;
- forming contacts to both the first region and the second region of the solar cell, said contacts comprising at least contacts to the second region on the front surface and external contacts being on the second surface, said part of said second surface having said dopand extending beyond the contact area of the contacts to said second region;
- and
- metallizing the vias in a way that the metallization forms a conduction path between the contacts to the second region on the front surface and at least one of the external contacts on the second surface.
Dependencies are inferred from the claim text.