Browse Prior Art Database

Stripping Promoter for Lift Off Mask

IP.com Disclosure Number: IPCOM000086435D
Original Publication Date: 1976-Sep-01
Included in the Prior Art Database: 2005-Mar-03
Document File: 2 page(s) / 38K

Publishing Venue

IBM

Related People

Carr, P: AUTHOR [+4]

Abstract

A thin stripping layer of a polyether sulfone facilitates lift-off of a multilayer metal lift-off structure.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 2

Stripping Promoter for Lift Off Mask

A thin stripping layer of a polyether sulfone facilitates lift-off of a multilayer metal lift-off structure.

The figure shows a typical structure in which a silicon wafer substrate 1 has a silicon dioxide layer 2 on its surface. Onto layer 2 is coated a thin ( 2000 Angstroms) layer 3 of polyether sulfone polymer. Onto layer 3 is coated a layer 4 of an organic polymer material such as a novolak resin based positive resist, which is baked to 210-230 degrees C to render it nonphotosensitive. On top of layer 4 is coated a methylsiloxane resin barrier layer 5 followed by a layer 6 of a radiation sensitive resist.

Layer 6 is subjected to radiation and is developed to provide a patterned relief image with opening 7, corresponding to the location where it is desired to form a metal layer on the layer 2. The resist mask 6 is then used to permit selective removal of the underlying layers 3, 4 and 5 to expose portions of the silicon dioxide layer 2.

A metal layer is then formed, such as by evaporation, over the entire surface of the structure including the exposed portions of layer 2. The lift-off structure and overlying metal are then removed by placing the structure in a suitable solvent or solvents, to leave only the patterned metal layer which is in contact with the silicon dioxide layer 2.

1

Page 2 of 2

2

[This page contains 2 pictures or other non-text objects]