05238499 is referenced by 236 patents and cites 31 patents.

A suitable inert gas such as argon or a mixture of inert and reactive gases such as argon and hydrogen is introduced onto the backside of wafers being processed in a CVD reactor during the deposition of tungsten or other metals, metal nitrides and silicides, to avoid deposition of material on the backside of the wafers being processed. Each process station includes a gas dispersion head disposed over a platen. A vacuum chuck including a number of radial and circular vacuum grooves in the top surface of the platen is provided for holding the wafer in place. A platen heater is provided under the platen. Backside gas is heated in and about the bottom of the platen, and introduced through a circular groove in the peripheral region outside of the outermost vacuum groove of the vacuum chuck. Backside gas pressure is maintained in this peripheral region at a level greater than the CVD chamber pressure. In this manner, backside gas vents from beneath the edge of the wafer on the platen and prevents the process gas from contacting the wafer backside. If the process gas is also to be prevented from contacting the periphery of the wafer frontside, a shroud is urged against the platen to direct the backside gas into a cavity formed between the shroud and the platen. This cavity contains the wafer frontside periphery, so that backside gas venting from between the shroud and the wafer frontside periphery excludes the process gas.

Title
Gas-based substrate protection during processing
Application Number
554225
Publication Number
5238499
Application Date
March 25, 1991
Publication Date
August 24, 1993
Inventor
Christopher W Burkhart
San Jose
CA, US
Barry L Chin
Sunnyvale
CA, US
Jeffrey C Benzing
San Jose
CA, US
Eliot K Broadbent
San Jose
CA, US
Everhardus P van de Ven
Cupertino
CA, US
Agent
Skjerven Morrill MacPherson Franklin & Friel
Assignee
Novellus Systems
CA, US
IPC
C23C 14/00
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