Varian Semiconductor Equipment Associates, Inc.

Axcelis Technologies, Inc.

James Carroll

Klaus Petry

Julian G Blake

Dale K Stone

David E Suuronen

Lyudmila Stone

Bryan C Lagos

Kurt T Decker-Lucke

Dave Wiederspahn

Dennis M Klesel

Tariq Fasheh

An electrostatic chuck is formed using materials that are optically transparent to a range of frequencies, such as infrared radiation. The invention discloses several methods for achieving optical transparency. The chuck electrode can be formed having a mesh pattern designed with a specific open area percentage to provide adequate wafer clamping force while still allowing sufficient levels of infrared radiation to pass through. Alternatively, the chuck electrode can also be made from a transparent conductive film. A workpiece is disposed on one surface of the chuck, and a radiative heat source is positioned on the opposite side of the chuck. A reflector plate may be used to reflect the infrared radiation toward the chuck and the wafer. The spacing of the radiation sources and the shape of the reflector plate may be modified to focus more radiation on a particular portion of the workpiece if desired.

Electrostatic chuck with radiative heating

An ion implanter includes a platen having a clamping surface configured to support a wafer for treatment with ions, the platen also having at least one pair of electrodes under the clamping surface, a clamping power supply configured to provide an AC signal to the at least one pair of electrodes and a sensed signal representative of the AC signal, and a controller. The controller is configured to receive the sensed signal from the clamping power supply when no wafer is clamped to the clamping surface. The controller is further configured to monitor the sensed signal and determine if the sensed signal is representative of deposits on the clamping surface exceeding a predetermined deposit threshold.

Platen clamping surface monitoring

A control for pressurizing a load lock. The control initiates pressurization of the loadlock interior by coupling a source of gas to the loadlock interior. A representative load lock includes a pressure sensor and multiple valves to atmosphere where at least one such valves is a passthrough valve for removal of and insertion of workpieces from and into a load lock interior. A second fast acting valve also opens to atmosphere. A pressure rise inside the loadlock interior is monitored and when the pressure reaches a threshold pressure above atmosphere the fast acting valve is opened to atmosphere. This second fast acting valve is configured to relieve overpressure from the passthrough valve prior to opening of said passthrough valve. Workpiece movement is accomplished with the aid of a robot which reaches into the loadlock interior as it is either depositing workpieces or retrieving them. This system and process minimizes particle contamination of the load lock interior as well as contamination in the region outside the loadlock near the passthrough valve and any scheduled workpieces.

Load lock control

The present invention relates to an electrostatic clamp and comprises a dielectric layer overlying an electrode and a doped region in the dielectric layer. The doped region of the dielectric layer is electrically conductive, and when the doped region is coupled to a circuit ground potential, the doped region of the dielectric layer is operable to bleed off charge which accumulates on a workpiece residing thereon during processing. The present invention further comprises a method of forming an electrostatic clamp which comprises the steps of forming an electrically insulating layer over an electrode and doping a portion of the electrically insulating layer, wherein the doped portion of the electrically insulating layer becomes electrically conductive.

Method and apparatus for the grounding of process wafers by the use of conductive regions created by ion implantation into the surface of an electrostatic clamp

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Amesbury, MA, United States of America

James Carroll