Chemically enhanced FIB repair of opaque defects on molybdenum silicide photomasks

J. David Casey Jr.; Andrew F. Doyle; Diane K. Stewart; David C. Ferranti; Mark L. Raphaelian; John C. Morgan

doi:10.1117/12.301221

12 February 1997 Chemically enhanced FIB repair of opaque defects on molybdenum silicide photomasks

J. David Casey Jr., Andrew F. Doyle, Diane K. Stewart, David C. Ferranti, Mark L. Raphaelian, John C. Morgan

Proceedings Volume 3236, 17th Annual BACUS Symposium on Photomask Technology and Management; (1997) https://doi.org/10.1117/12.301221
Event: 17th Annual BACUS Photomask Technology and Management, 1997, Redwood City, CA, United States

Abstract

The characteristics of an ideally repaired opaque defect on a molybdenum silicide (MoSi_aO_bN_c) photomask are: (1) the total removal of the MoSi_aO_bN_c defect, leaving no residual MoSi_aO_bN_c; (2) a smooth, level quartz surface (no over-etch) after the MoSi_aO_bN_c is removed; (3) minimal riverbedding of the quartz at the perimeter of the MoSi_aO_bN_c defect; and (4) maximum light transmission (%T) at the i-line (365 nm) and DUV (248 nm) lithographic wavelengths. Achieving these ideal repair characteristics is becoming increasingly difficult as the patterned features become smaller, as the lithographic wavelength becomes shorter and as phase shifting mechanisms are implemented. A chemical process has been developed to enhance the FIB (focused ion beam) etching of MoSi_aO_bN_c defects. Using this chemical process, a FIB protocol has been developed which enhances the removal of a MoSi_aO_bN_c defect while inhibiting the removal of quartz. AFM (atomic force microscopy) indicates that (1) MoSi_aO_bN_c is totally removed, (2) the quartz remains smooth and level (no over-etch), and (3) the riverbends are, at this time, 10 - 45 nm; our target is 1 - 15 nm. The MoSi_aO_bN_c etch process reduces optical staining due to implanted gallium

Citation Download Citation

J. David Casey Jr., Andrew F. Doyle, Diane K. Stewart, David C. Ferranti, Mark L. Raphaelian, and John C. Morgan "Chemically enhanced FIB repair of opaque defects on molybdenum silicide photomasks", Proc. SPIE 3236, 17th Annual BACUS Symposium on Photomask Technology and Management, (12 February 1997); https://doi.org/10.1117/12.301221

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available