Method of cleaning an exposed surface of a back contacted solar cell by depositing and removing a sacrificial layer

US10847662B2 · kind B2 · utility

Assignee

• IMEC VZW · BE

Inventors

• Hariharsudan Sivaramakrishnan Radhakrishnan · Leuven, BE
• Jef Poortmans · Kessel-Lo, BE

Key dates

• Filing date: May 30, 2019
• Grant date: Nov 24, 2020
• Expiry date: May 30, 2039

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P70/50

Abstract

A method is provided for creating an interdigitated pattern for a back-contacted solar cell, including deposition of a first passivation layer stack including a-Si of a first doping type, patterning the first passivation layer stack by using a first dry etching process to create one or more regions including the a-Si of the first doping type and one or more exposed regions of the surface, cleaning the one or more exposed regions of the surface from contaminants remaining from the first dry etching process, and depositing a second passivation layer stack including a-Si of a second doping type different from the first doping type to create the interdigitated pattern together with the patterned first passivation layer stack. The cleaning may include depositing a sacrificial layer at least on the exposed regions of the surface, and removing the sacrificial layer by a second dry etching process, at a temperature not exceeding 250° C.