Formation of metal structures in solar cells

Patent metadata

Field	Value
Publication number	US-8945978-B2
Application number	US-201313931520-A
Country	US
Kind code	B2
Filing date	Jun 28, 2013
Priority date	Jun 28, 2013
Publication date	Feb 3, 2015
Grant date	Feb 3, 2015

Abstract

A metal contact of a solar cell is formed by electroplating copper using an electroplating seed that is formed on a dielectric layer. The electroplating seed includes an aluminum layer that connects to a diffusion region of the solar cell through a contact hole in the dielectric layer. A nickel layer is formed on the aluminum layer, with the nickel layer-aluminum layer stack forming the electroplating seed. The copper is electroplated in a copper plating bath that has methanesulfonic acid instead of sulfuric acid as the supporting electrolyte.

First claim

What is claimed is:

1. A method of fabricating a solar cell, the method comprising:
forming an aluminum layer on a dielectric layer to connect to a diffusion region of the solar cell through a contact hole in the dielectric layer;
forming an electroplating seed, wherein said forming the electroplating seed includes forming a nickel layer on the aluminum layer; and
forming a metal contact that connects to the diffusion region of the solar cell, wherein said forming the metal co…

Assignees

• Sunpower Corp

Inventors

• Behnke Joseph Frederick

Classifications

• H10F77/219

  Electricity · mapped topic

• H10F10/146

  Electricity · mapped topic

• H10F10/14

  Electricity · mapped topic

• H10F77/211 Primary

  Electricity · mapped topic

• H01L31/18 Primary

  Electricity · mapped topic