Method and system for gas flow mitigation of molecular contamination of optics
| DWPI Title: Method for determining optimized purge gas flow in semi-conductor inspection metrology or lithography apparatus, involves transporting released contaminant from vicinity of desorption surface to output port |
| Abstract: 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. |
| Use: Method for determining optimized purge gas flow in semi-conductor inspection metrology or lithography apparatus. |
| Advantage: The process for determining and creating optimal gas flow in semi-conductor inspection metrology or lithography apparatus is performed to decrease the concentration of contaminants within the semi-conductor inspection metrology or lithography apparatus in efficient manner. |
| Novelty: The method involves identifying desorption surface in semi-conductor inspection metrology or lithography apparatus (201), desorption rate associated with desorption surface and contaminant released from desorption surface. The purge gas is introduced into semi-conductor inspection metrology or lithography apparatus through input port with optimized gas velocity and gas flow rate. The released contaminant is transported from vicinity of desorption surface to output port. |
| Filed: 8/22/2014 |
| Application Number: US14466516A |
| Tech ID: SD 12479.2 |
| This invention was made with Government support under Contract No. DE-NA0003525 awarded by the United States Department of Energy/National Nuclear Security Administration. The Government has certain rights in the invention. |
| Data from Derwent World Patents Index, provided by Clarivate All rights reserved. Republication or redistribution of Clarivate content, including by framing or similar means, is prohibited without the prior written consent of Clarivate. Clarivate and its logo, as well as all other trademarks used herein are trademarks of their respective owners and used under license. |