Method and system for gas flow mitigation of molecular contamination of optics
A computer-implemented method for determining an optimized purge gas flow in a semi-conductor inspection metrology or lithography apparatus, comprising receiving a permissible contaminant mole fraction, a contaminant outgassing flow rate associated with a contaminant, a contaminant mass diffusivity, an outgassing surface length, a pressure, a temperature, a channel height, and a molecular weight of a purge gas, calculating a flow factor based on the permissible contaminant mole fraction, the contaminant outgassing flow rate, the channel height, and the outgassing surface length, comparing the flow factor to a predefined maximum flow factor value, calculating a minimum purge gas velocity and a purge gas mass flow rate from the flow factor, the contaminant mass diffusivity, the pressure, the temperature, and the molecular weight of the purge gas, and introducing the purge gas into the semi-conductor inspection metrology or lithography apparatus with the minimum purge gas velocity and the purge gas flow rate.
- Issue Date:
- OSTI Identifier:
- 1417885
- Assignee:
- National Technology & Engineering Solutions of Sandia, LLC (Albuquerque, NM) SNL-A
- Patent Number(s):
- 9,874,512
- Application Number:
- 14/466,516
- Contract Number:
- AC04-94AL85000
- Resource Relation:
- Patent File Date: 2014 Aug 22
- Research Org:
- Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
- Sponsoring Org:
- USDOE
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 42 ENGINEERING
- Full Text
- View Full Text
Other works cited in this record:
Extreme Ultraviolet Light Source With A Debris-Mitigated And Cooled Collector Opticspatent-application, February 2012
- Abhari, Reza; Giovannini, Andrea; Rollinger, Bod
- US Patent Application 13/262184; 20120025109
Similar records in DOepatents and OSTI.GOV collections: