Browse Prior Art Database

Multilayer Resist for Releasing Hardened Resist

IP.com Disclosure Number: IPCOM000062425D
Original Publication Date: 1986-Nov-01
Included in the Prior Art Database: 2005-Mar-09
Document File: 2 page(s) / 83K

Publishing Venue

IBM

Related People

Holland, SP: AUTHOR [+2]

Abstract

When fabricating semiconductors, an alternative method for removing hardened photoresist which does not utilize plasma ashing techniques involves the use of a photoresist release film. Photoresists frequently require ultraviolet (UV) light hardening and a bake cycle in order to withstand subsequent high temperature plasma processing. Once hardened, the only way to remove a photoresist is by plasma ashing in oxygen. However, this is not desirable when the underlying material is also etched in a plasma ash. Fig. 1 shows a cross-section of a semiconductor structure 10 with two levels of metal, i.e., M1 metal lines 11 and a second level metal 12, with a polyimide insulator 13 therebetween. Atop the second level metal 12 is a photoresist release film 14, poly(dimethlyglutarimide) or PMGI, and another photoresist layer 15.

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 62% of the total text.

Page 1 of 2

Multilayer Resist for Releasing Hardened Resist

When fabricating semiconductors, an alternative method for removing hardened photoresist which does not utilize plasma ashing techniques involves the use of a photoresist release film. Photoresists frequently require ultraviolet (UV) light hardening and a bake cycle in order to withstand subsequent high temperature plasma processing. Once hardened, the only way to remove a photoresist is by plasma ashing in oxygen. However, this is not desirable when the underlying material is also etched in a plasma ash. Fig. 1 shows a cross-section of a semiconductor structure 10 with two levels of metal, i.e., M1 metal lines 11 and a second level metal 12, with a polyimide insulator 13 therebetween. Atop the second level metal 12 is a photoresist release film 14, poly(dimethlyglutarimide) or PMGI, and another photoresist layer 15. The composite photoresist (14 and
15) is used to pattern the second level metal 12. The polyimide insulator 13 is vulnerable to oxygen plasma etching and must be protected during a photoresist- stripping process. Fig. 2 shows the composite photoresist layers 14 and 15 after pattern development. PMGI is developed without light exposure by the basic developer used to develop the imaging resist film 15. The resist stack structure, depicted in Fig. 2, is achieved in one development step. To dry etch the second level metal 12, photoresist layer 15 is UV hardened and baked so that the photoresist 15 does not...