Life extension of photoresist developer solutions
Number of patents in Portfolio can not be more than 2000
United States of America Patent
Stats
-
Dec 29, 1998
Grant Date -
N/A
app pub date -
Aug 11, 1997
filing date -
Aug 11, 1997
priority date (Note) -
Expired
status (Latency Note)
Importance
Abstract
This invention relates to a method for increasing the effective process life and chemical efficiency of use of aqueous-based developer solutions used for chemical development of photoresists such as are used in the printed circuit industry. The activity is maintained by regenerating some of byproducts during the process to active carbonate, by controlled additions of alkaline hydroxide instead if conventional carbonate solution. The pH and thus the development speed can automatically be controlled at any desired constant value. This invention allows simple automation of printed circuit photoresist development, with reduced chemical costs and increased chemical usage efficiency and thus reducing the industrial waste volume.
First Claim
Family
International Classification(s)
Cited Art Landscape
Patent Citation Ranking
Recipient Email Address
Recipient Email Address
Comment
Recipient Email Address
Add to Portfolio(s)
To add this patent to one, or more, of your portfolios, simply click the add button.
This Patent is in these Portfolios:
Add to additional portfolios:
Last Refreshed On:
Changes done successfully