Low vapor pressure, low debris solid target for EUV production

US6835944B2 · kind B2 · utility

Assignee

• University of Central Florida Research Foundation · US

Inventors

• Rocco A. Orsini · Long Beach, US
• Michael B. Petach · Redondo Beach, US
• Mark E. Michaelian · Torrance, US
• Henry Shields · San Diego, US
• Roy D. McGregor · Corning, US
• Steven W. Fornaca · Torrance, US

Key dates

• Filing date: Oct 11, 2002
• Grant date: Dec 28, 2004
• Expiry date: Mar 24, 2023

Classification

• Technology area (CPC H): Electricity
• CPC primary: H05G2/00
• WIPO field: Medical technology
• WIPO sector: Instruments

Abstract

An EUV radiation source that creates a stable solid filament target. The source includes a nozzle assembly having a condenser chamber for cryogenically cooling a gaseous target material into a liquid state. The liquid target material is filtered by a filter and sent to a holding chamber under pressure. The holding chamber allows entrained gas bubbles in the target material to be condensed into liquid prior to the filament target being emitted from the nozzle assembly. The target material is forced through a nozzle outlet tube to be emitted from the nozzle assembly as a liquid target stream. A thermal shield is provided around the outlet tube to maintain the liquid target material in the cryogenic state. The liquid target stream freezes and is vaporized by a laser beam from a laser source to generate the EUV radiation.