Control of Developed Photoresist Profile
Original Publication Date: 1978-Apr-01
Included in the Prior Art Database: 2005-Feb-20
Positive photoresists, such as m-cresol formaldehyde novolak resins with diazo ketone sensitizers (available from the Shipley Company), when developed in strong hydroxide developer, provide substantially vertical side-wall profiles. Immersion in bromonapthalene for about 8 minutes followed by a 15-second rinse in a fluorocarbon and air drying prior to standard development provides a profile which tapers in a direction toward the resist retained after development. Applications utilizing the modified profile include those in which the developed photoresist remains as part of the structure being fabricated where vertical profiles are undesirable.