04019109 is referenced by 60 patents and cites 9 patents.

Alignment of a mask and a semiconductor wafer to be processed is effected by orthogonal and angular movements of the mask singly and in combination. A carrier for the mask is supported on four orthogonally positioned transducers which, when actuated to elongate or contract, produce carrier translational movement in either or both orthogonal directions and/or rotational movement by selective elongation and contraction of one or more transducers. Actuation of the transducers and the alignment are obtained by signals from a feedback system including photon detection and multiple frequency oscillation utilizing alignment marks on the mask and the wafer.

Title
Alignment system and method with micromovement stage
Application Number
469154
Publication Number
4019109
Application Date
April 5, 1976
Publication Date
April 19, 1977
Inventor
Paul A Sullivan
Santa Monica
CA, US
John H McCoy
Newbury Park
CA, US
Agent
W J Bethurum
W H MacAllister
Lewis B Sternfels
Assignee
Hughes Aircraft Company
CA, US
IPC
G05B 19/18
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