Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

Step Coverage Process With Reactive Ion Etching Using Thermal Resist Effects

IP.com Disclosure Number: IPCOM000087546D
Original Publication Date: 1977-Feb-01
Included in the Prior Art Database: 2005-Mar-03
Document File: 2 page(s) / 46K

Publishing Venue

IBM

Related People

Bondur, JA: AUTHOR [+3]

Abstract

For reliable step coverage of a metal interconnection layer, etched oxide slope angles of 50 degrees to 60 degrees are desirable, as shown in Fig. 1. Such a profile is obtained with a low etch bias and tolerance by first applying a layer of positive photoresist of the phenolformaldehyde novolak resin type, prebaking and then exposing, using projection, proximity or contact imaging. The layer is baked, prior to development, for times and at temperatures to produce the desired resist profile upon development with suitable developer.

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

Step Coverage Process With Reactive Ion Etching Using Thermal Resist Effects

For reliable step coverage of a metal interconnection layer, etched oxide slope angles of 50 degrees to 60 degrees are desirable, as shown in Fig. 1. Such a profile is obtained with a low etch bias and tolerance by first applying a layer of positive photoresist of the phenolformaldehyde novolak resin type, prebaking and then exposing, using projection, proximity or contact imaging. The layer is baked, prior to development, for times and at temperatures to produce the desired resist profile upon development with suitable developer.

For a .45 second exposure and 30 second development in straight developer, the dependence of line width and slope profile with temperature is shown in Figs. 2(a)-(d), and with time is shown in Fig. 3(a)-(d). The resist is developed and the exposed oxide is etched by reactive ion etching in a diode configuration with CF(4) gas to produce the oxide profile shown in Fig. 1. This profile is suitable for metallization with good step coverage.

1

Page 2 of 2

2

[This page contains 6 pictures or other non-text objects]