Heated chuck for laser thermal processing

US7731798B2 · kind B2 · utility

Assignee

• Ultratech · US

Inventors

• Iqbal Shareef · Fremont, US
• Igor Landau · Palo Alto, US
• David A. Markle · Saratoga, US
• Somit Talwar · Palo Alto, US
• Michael O. Thompson · Ithaca, US
• Ivelin Angelov · San Jose, US
• Senquan Zhou · San Jose, US

Key dates

• Filing date: Dec 1, 2004
• Grant date: Jun 8, 2010
• Expiry date: Oct 18, 2025

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B23K26/703
• WIPO field: Machine tools
• WIPO sector: Mechanical engineering

Abstract

A chuck for supporting a wafer and maintaining a constant background temperature across the wafer during laser thermal processing (LTP) is disclosed. The chuck includes a heat sink and a thermal mass in the form of a heater module. The heater module is in thermal communication with the heat sink, but is physically separated therefrom by a thermal insulator layer. The thermal insulator maintains a substantially constant power loss at least equal to the maximum power delivered by the laser, less that lost by radiation and convection. A top plate is arranged atop the heater module, supports the wafer to be processed, and provides a contamination barrier. The heater module is coupled to a power supply that is adapted to provide varying amounts of power to the heater module to maintain the heater module at the constant background temperature even when the wafer experiences a spatially and temporally varying heat load from an LTP laser beam. Thus, heat from the laser is transferred from the wafer to the heat sink via the heater module and the insulator layer. In the absence of any laser heating, heat is also transferred from the heater module to the wafer as needed to maintain the consta…