Process for preparing single crystal
CA 1237640 A · Owner: Nippon Telegraph And Telephone Corporation · Inventors: Kotani, Toshihiro; Kawasaki, Akihisa; Tada, Kohji
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract:, The invention provides a process for preparing a single crystal which comprises drawing up a single crystal by the Czochralski process and cooling it from a temperature not lower than 600°C under a reduced pressure or in vacuo. The process provides a single crystal having a dislocation density of 1.5 x 104 cm2 or less.
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
- Granted June 7, 1988. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended June 7, 2005.
- 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.