Cleaning process for photomasks

Abstract

A photomask provided with a light-shielding coating on a surface of a glass substrate is cleaned with O 3 gas solved water to eliminate organic substances adhered on a surface of the photomask (S 120 ). Using an alkaline chemical such as alkaline ionized water or hydrogenated water, the photomask is then cleaned to eliminate contamination (S 122 ). After completion of these cleaning steps, the photomask is dried (S 124 ).

1 . A cleaning process for a photomask provided with a light-shielding coating on a surface of a glass substrate, which comprises the following steps of: 
 cleaning said photomask with O 3  gas solved water;    eliminating contamination adhered on a surface of said photomask; and    drying said photomask, wherein said photomask is a halftone photomask having a MoSi light-shielding coating.    
   
   
       2 - 5 . (canceled)  
   
   
       6 . A cleaning process according to  claim 1 , wherein ultrasonic cleaning is conducted in at least one of said steps of cleaning said photomask and eliminating contamination.