Browse Prior Art Database

Etching of Polyimide Films

IP.com Disclosure Number: IPCOM000090813D
Original Publication Date: 1969-Jul-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 1 page(s) / 12K

Publishing Venue

IBM

Related People

Boles, JG: AUTHOR [+2]

Abstract

Etched image patterns are developed in polyimide films bonded to copper substrates without intervening adhesives. Advantages accrue in definition and detail of reproduced image elements, especially in films less than .002" thick, and in reduction of corrosive effects encountered when more caustic etchants are employed. More caustic etchants tend to attack the resist coating layer forming the protective mask over the not to be etched areas of the film. The surface of the polyimide, e.g., KAPTON*, film is prepared by degreasing in trichloroethylene. The dried film surface is coated with a thin layer of full strength polyvinylcinnamate liquid photoresist material by the dip withdrawal method. The withdrawal rate of 2 inches per minute is appropriate.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 61% of the total text.

Page 1 of 1

Etching of Polyimide Films

Etched image patterns are developed in polyimide films bonded to copper substrates without intervening adhesives. Advantages accrue in definition and detail of reproduced image elements, especially in films less than .002" thick, and in reduction of corrosive effects encountered when more caustic etchants are employed. More caustic etchants tend to attack the resist coating layer forming the protective mask over the not to be etched areas of the film. The surface of the polyimide, e.g., KAPTON*, film is prepared by degreasing in trichloroethylene. The dried film surface is coated with a thin layer of full strength polyvinylcinnamate liquid photoresist material by the dip withdrawal method. The withdrawal rate of 2 inches per minute is appropriate. The sensitive resist layer is air-dried for at least 10 minutes and then baked at 140 degrees F for 15 minutes. The sensitive resist layer is exposed to actinic light forming the desired image pattern. The resist layer is developed, rinsed in water and dried. Patterns requiring tighter tolerance control over spacing and definition of pattern elements are spray-developed with trichloroethylene, dried, dipped in a liquid cleaning solution such as dichromate-sulphuric cleaning agent, rinsed in water, and dried. The object produced in the previous step, polyimide film masked by developed resist, is baked for 6-10 minutes at 250 degrees C and allowed to cool. This hardens the masking resist. The ob...