TRENCH PROCESS AND STRUCTURE FOR BACKSIDE CONTACT SOLAR CELLS WITH POLYSILICON DOPED REGIONS

摘要

A solar cell includes polysilicon P-type and N-type doped regions on a backside of a substrate, such as a silicon wafer. A trench structure separates the P-type doped region from the N-type doped region. Each of the P-type and N-type doped regions may be formed over a thin dielectric layer. The trench structure may include a textured surface for increased solar radiation collection. Among other advantages, the resulting structure increases efficiency by providing isolation between adjacent P-type and N-type doped regions, thereby preventing recombination in a space charge region where the doped regions would have touched.

主权项

1. A solar cell comprising:
a solar cell substrate having a front side configured to face the sun during normal operation and a backside opposite the front side; a P-type doped region and an N-type doped region of the solar cell over the backside of the solar cell substrate; a trench between the P-type doped region and the N-type doped region, the trench physically separating the P-type doped region from the N-type doped region and extending into the solar cell substrate; a first metal contact finger that is electrically connected to the P-type doped region; and a second metal contact finger that is electrically connected to the N-type doped region.