Fabrication of polycrystalline thin films by pulsed laser processing

US5714404A · kind A · utility

Assignee

• The Regents of the University of California · US

Inventors

• Fred Mitlitsky · Livermore, US
• Joel Truher · San Rafael, US
• James L. Kaschmitter · Pleasanton, US
• Nicholas Colella · Pleasanton, US

Key dates

• Filing date: Nov 18, 1993
• Grant date: Feb 3, 1998
• Expiry date: Nov 18, 2013

Classification

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

Abstract

A method for fabricating polycrystalline thin films on low-temperature (or high-temperature) substrates which uses processing temperatures that are low enough to avoid damage to the substrate, and then transiently heating select layers of the thin films with at least one pulse of a laser or other homogenized beam source. The pulse length is selected so that the layers of interest are transiently heated to a temperature which allows recrystallization and/or dopant activation while maintaining the substrate at a temperature which is sufficiently low to avoid damage to the substrate. This method is particularly applicable in the fabrication of solar cells.