公开(公告)号：DE3751658T2

公开(公告)日：1996-07-04

申请号：DE3751658

申请日：1987-03-10

Applicant: IBM

Inventor： INDYK RICHARD FRANCIS ,  LAMELAS FRANCISCO JAVIER ,  NEISSER MARK OLIVER

IPC: H01L23/12 ,  H01L21/48 ,  H01L23/498 ,  H05K3/02 ,  H05K3/04 ,  H05K3/14 ,  H05K3/16 ,  H05K3/24 ,  H05K3/28 ,  H01L23/48

Abstract: Disclosed is a screening paste for covering a selected portion of a metallurgical pattern (12, 14) on a substrate (10) while leaving other metallurgy uncovered. The paste (16) is free of polymers and consists, in one example, of 75-80% of a ceramic particulate (such as alumina), 2-8% amorphous fumed silica and 15-20% of linear alcohol. The linear alcohol serves as a vehicle to deliver the solid particles in the paste. In use, after covering the selected portion (12) of the metallurgical pattern with the paste, the alcohol content therein is expelled by subjecting to vacuum treatment at room temperature or heating to a low temperature below about 275 DEG C thereby obtaining an inert, dry and crackfree protective coating. Upon evaporation of a new metal layer (18) onto the substrate and removal of the protective coating and new metal layer from everywhere except the uncovered metallurgy, the metallurgical pattern (14) is selectively coated with the new metal (20).

公开(公告)号：DE3751658D1

公开(公告)日：1996-02-15

申请号：DE3751658

申请日：1987-03-10

Applicant: IBM

Inventor： INDYK RICHARD FRANCIS ,  LAMELAS FRANCISCO JAVIER ,  NEISSER MARK OLIVER

IPC: H01L23/12 ,  H01L21/48 ,  H01L23/498 ,  H05K3/02 ,  H05K3/04 ,  H05K3/14 ,  H05K3/16 ,  H05K3/24 ,  H05K3/28 ,  H01L23/48

Abstract: Disclosed is a screening paste for covering a selected portion of a metallurgical pattern (12, 14) on a substrate (10) while leaving other metallurgy uncovered. The paste (16) is free of polymers and consists, in one example, of 75-80% of a ceramic particulate (such as alumina), 2-8% amorphous fumed silica and 15-20% of linear alcohol. The linear alcohol serves as a vehicle to deliver the solid particles in the paste. In use, after covering the selected portion (12) of the metallurgical pattern with the paste, the alcohol content therein is expelled by subjecting to vacuum treatment at room temperature or heating to a low temperature below about 275 DEG C thereby obtaining an inert, dry and crackfree protective coating. Upon evaporation of a new metal layer (18) onto the substrate and removal of the protective coating and new metal layer from everywhere except the uncovered metallurgy, the metallurgical pattern (14) is selectively coated with the new metal (20).