Emitter wrap-through back contact solar cells on thin silicon wafers
US7649141B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 29, 2004 |
| Grant date | Jan 19, 2010 |
| Priority date | — |
| Expiry date | Oct 11, 2026 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E10/547
Abstract
A thin emitter wrap-through solar cell and method for making a thin emitter wrap-through solar cell. The cell preferably includes a silicon wafer substrate having a thickness of less than 280 microns. The p-type area on the back side of the cell is minimized, which maximizes the collector area and reduces or eliminates stress due to passivation of the p-type area, which is required for conventional solar cells. The efficiency of the cell of the present invention peaks for a much smaller thickness than that for conventional cells. Thus thin wafers of inexpensive, lower quality silicon may be used without a significant efficiency penalty, providing a large cost advantage over other solar cell configurations. Vias through the substrate, which connect emitter layers on the front and back surfaces of the substrate, may consist of holes which are doped, or alternatively may be solid doped channels formed by migration of a solvent, which preferably contains a dopant, caused by a gradient-driven process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.