Process for making hard pellicles

• Main Author: BELLMAN ROBERT A
• Format: Patent
• Language: English
• Published: 24.02.2005
• Edition: 7
• Subjects: APPARATUS SPECIALLY ADAPTED THEREFOR; CHEMICAL SURFACE TREATMENT; CHEMISTRY; CINEMATOGRAPHY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; ELECTROGRAPHY; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; HOLOGRAPHY; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; MATERIALS THEREFOR; METALLURGY; ORIGINALS THEREFOR; PHOTOGRAPHY; PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES,e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTORDEVICES; PHYSICS; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION; TECHNICAL SUBJECTS COVERED BY FORMER USPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS

Disclosed is a process for making thin hard pellicle for photomasks used in projection photolithography. The process can be used for making thin hard pellicles comprising a pellicle layer having a thickness in the range of about 5 to 120 mum and a mount frame attached to the peripheral area of a surface of the pellicle layer. The pellicle layer can consist essentially of a material selected from silica, fluorine doped silica, aluminum doped silica, methylated silica, fluorinated and methylated silica, fluorinated aluminum doped silica, CaF2, MgF2, BaF2 and SiC. The mount frame is preferred to have substantially the same CTE of the pellicle layer to minimize stress caused by temperature change. The mount frame is preferred to be porous to the purging gas. The process for making the hard pellicle involves deposition of an intermediate layer comprising a hydrogenated amorphous silicon layer on a flat substrate, deposition of the pellicle layer on the intermediate layer, mounting the frame to the pellicle layer and the separation of the pellicle from the substrate by heat treatment.