Grain growth for solar cells

摘要

A solar cell can include a silicon layer formed over a silicon substrate. The silicon layer can have a P-type doped region and an N-type doped region. Portions of the silicon layer can have a grain size larger than other portions of the silicon layer. For example, larger grains of the silicon layer formed within a depletion region between P-type and N-type doped regions can minimize recombination loss at the P-type and N-type doped region boundaries and improve solar cell efficiency.

主权项

1. A method of fabricating a solar cell, the method comprising:
forming upper regions, angled regions and lower regions of a silicon substrate, wherein the upper regions and the lower regions are substantially coplanar; forming a silicon layer over the silicon substrate; applying a laser to the silicon layer resulting in portions of the silicon layer over the upper regions and lower regions having a larger grain size than other portions of the silicon layer over angled regions of the silicon substrate; and driving dopants into the silicon layer resulting in P-type doped regions and N-type doped regions, the P-type doped regions and N-type doped regions abutting in a contiguous portion of the silicon layer.