Browse Prior Art Database

Piezoelectric Actuated Wafer Gripper

IP.com Disclosure Number: IPCOM000035133D
Original Publication Date: 1989-Jun-01
Included in the Prior Art Database: 2005-Jan-28
Document File: 2 page(s) / 43K

Publishing Venue

IBM

Related People

Liporace, JW: AUTHOR

Abstract

A wafer gripper has been developed which uses piezoelectric elements to actuate the fingers used for handling the wafer. It makes it possible to pick and place semiconductor wafers in the appropriate processing tool thereby minimizing surface contamination which may occur with more conventional approaches.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 87% of the total text.

Page 1 of 2

Piezoelectric Actuated Wafer Gripper

A wafer gripper has been developed which uses piezoelectric elements to actuate the fingers used for handling the wafer. It makes it possible to pick and place semiconductor wafers in the appropriate processing tool thereby minimizing surface contamination which may occur with more conventional approaches.

The actuator 1 in Figs. la and 1b consists of a ceramic plate containing piezoelectric crystals of opposite polarization, bimorphs, bonded together so that a positive voltage is applied to one side and then to the other. The application of voltage causes the crystals to expand or contract and a bending movement is imparted to the actuator 1. A top support mounting plate 2 secures the actuator to a printed circuit board 3 from where voltage is applied. A tip mounting plate 4 secures the finger 5, which does the actual handling of the wafer, to the actuator
1.

The actuator is mounted in a support housing 6 in Fig. 2 by means of a spacer support 7 which functions to accurately position the gripper finger 5. When an appropriate voltage is applied to the actuator 1 it will flex outward away from the center by the distance delta-X 8 so that the fingers clear the wafer 9, which is to be picked up and or placed on the processing tool. When the voltage is applied to the other side of the actuator, the actuator flexes inward a distance of delta-X 10 so that the corresponding finger 5 is beneath the wafer 9 in a position to lift it.

In...