Wafer processing apparatus, wafer processing method, and semiconductor substrate fabrication method
CA 2229975 C · Owner: Yanagita, Kazutaka · Inventors: Sakaguchi, Kiyofumi; Harada, Masakazu; Uehara, Fumio
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An ultrasonic bath (30) is arranged below a wafer processing bath (10). Wafers (40) are processed while ultrasonic waves are transmitted from the ultrasonic bath (30) to the wafer processing bath (10). The wafers (40) are processed while being entirely dipped into the wafer processing bath (10) and rotated by wafer rotating rods (53).
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed February 18, 1998 and granted February 18, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 18, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 18, 2020.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.