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Patent Searching and Data


Title:
VERTICAL DRIVE UNIT FOR WAFER CHUCK
Document Type and Number:
Japanese Patent JPS6211246
Kind Code:
A
Abstract:

PURPOSE: To drive a table vertically without a time delay by mounting a voice coil to the table while being positioned in the magnetic field of a permanent magnet and conducting the voice coil.

CONSTITUTION: A mask 1, a table 2, small holes 3 and a vacuum hose 4 are manufactured and arranged in the same manner as conventional devices. A voice coil 6 is fixed vertically to the lower surface of the table 2, and releasably supported movably in the direction of an axis while being crossed at right angles with the magnetic field of a permanent magnet 7. A wafer 5 is sucked onto the table 2 under a vacuum, and the voice coil is conducted. The coil 6 is driven vertically by the direction of conduction, driving force is accurately proportional to a conduction current value, and the variation of driving force quickly responds to a current change, and delay may be regarded as zero on practical precision.


Inventors:
AIKO KENJI
NAMIKI YOSHIJI
Application Number:
JP13682985A
Publication Date:
January 20, 1987
Filing Date:
June 25, 1985
Export Citation:
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Assignee:
HITACHI ELECTR ENG
International Classes:
H01L21/68; B23Q5/28; H01L21/67; (IPC1-7): B23Q5/28; H01L21/68
Attorney, Agent or Firm:
Masami Akimoto