Contrast tuning, image reversal, and automated track developing

Author

Lamarre, Philip A. ; McTaggart, Rebecca Ann ; Mozzi, Robert L.

Author_Institution

Raytheon Co., Lexington, MA, USA

Volume

1

Issue

3

fYear

1988

fDate

8/1/1988 12:00:00 AM

Firstpage

98

Lastpage

104

Abstract

An experiment was conducted to determine if contrast tuning could be performed on an automated track developer using a standard spray versus an ultrasonic nozzle. GaAs wafers were patterned with a linear variable neutral density filter (LVNDF) and developed by spray and an ultrasonic nozzle. The ultrasonic nozzle produced a lower chemical contrast than the standard spray development. This lower chemical contrast used in conjunction with image reversal makes photoresist sidewalls more retrograde, which is advantageous in GaAs processing for metal liftoff. In addition to contrast tuning, the LVNDF technique is described that was used to quickly and easily compare the contrasts of the two development systems. With the LVNDF mask, chemical contrast as well as process uniformity could be quickly measured

Keywords

III-V semiconductors; gallium arsenide; photolithography; GaAs processing; LVNDF; automated track developer; automated track developing; chemical contrast; contrast tuning; experiment; linear variable neutral density filter; metal liftoff; photoresist sidewalls; process uniformity; retrograde sidewalls; semiconductors; standard spray; ultrasonic nozzle; Automation; Chemical processes; Gallium arsenide; MMICs; Monitoring; Nonlinear filters; Resists; Spraying; Standards development; Throughput;

fLanguage

English

Journal_Title

Semiconductor Manufacturing, IEEE Transactions on

Publisher

ieee

ISSN

0894-6507

Type

jour

DOI

10.1109/66.4380

Filename

4380