04770590 is referenced by 171 patents and cites 12 patents.

A wafer transfer mechanism used for transferring wafers between cassettes and a boat uses sensors to detect and to measure any offset of the actual center of each wafer being transferred with respect to the expected or precalibrated center of that wafer. An appropriate adjustment is made to effectively eliminate such offset so that each wafer can be transferred throughout the system without any edge contact between a wafer and the boat or the cassette. The system also includes a boat exchange unit having a rotatable turntable which is used in association with two boats. The boat exchange unit permits a continuous mode operation in which one boat can be undergoing a loading or unloading of wafers at one station on the turntable while another boat is at or is moving to or from a heating chamber loading or unloading station on the turntable.

Title
Method and apparatus for transferring wafers between cassettes and a boat
Application Number
6/864077
Publication Number
4770590
Application Date
May 16, 1986
Publication Date
September 13, 1988
Inventor
Gary W Yee
Santa Clara
CA, US
Donald L Schuman
Saratoga
CA, US
Katsuhito Nishikawa
San Jose
CA, US
James E Herlinger
Palo Alto
CA, US
Lynn Weber
Saratoga
CA, US
Jean B Hugues
Tempe
AZ, US
Agent
Donald C Feix
Assignee
Silicon Valley Group
CA, US
IPC
C23C 15/00
B23K 9/00
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