Applied Materials, Inc.

Andros Incorporated

Davood Khalili

Bok Hoen Kim

Martin Jay Seamons

Mario Dave Silvetti

Kevin G Williams

Lloyd M Berken

Nam Le

Emery Major

Ameeta Madhava

Ken Christensen

Alexey Goder

Steven Drucker

Emanuele Cappello

Backside particle contamination of semiconductor wafers subjected to chemical vapor deposition is significantly reduced by optimizing various process parameters, alone or in combination. A high quality oxide seasoning layer is deposited to improve adhesion and trapping of contaminants remaining after a prior chamber cleaning step. Second, wafer pre-heating reduces thermal stress on the wafer during physical contact between the wafer and heater. Third, the duration of the gas stabilization flow of thermally reactive process gas species prior to CVD reaction is reduced, thereby preventing side products produced during this stabilization flow from affecting the wafer backside. Fourth, the wafer heater is redesigned to minimize physical contact between the heater surface and the wafer backside. Redesign of the wafer heater may include providing only a few, small projections from the top wafer surface, and also may include providing a continuous circumferential rim supporting the edge of the wafer to interfere with the flow of process gases to the wafer backside during processing.

Method and apparatus for reducing particle contamination on wafer backside during CVD process

An improved apparatus and method for measuring the concentration of carbon dioxide in respiratory gases. The apparatus is a non-dispersive gas analyzer attached in series with the respiratory airway which is universally compatible with any host system. The analyzer includes a housing which supports a sample cell containing the respiratory gases, and which contains an infrared radiation source encased in shock absorbing material, means for directing the radiation into a collimated beam path through the sample cell, means for splitting the beam path and directing it towards a pair of infrared detectors for measuring the amount of absorption of carbon dioxide in the sample cell. The analyzer is further improved by the use of two heating servos, one for regulating the temperature of the sample cell windows in order to inhibit condensation build-up and one for regulating the ambient temperature surrounding the detectors so as to ensure more accurate measurements. Calibration means is included within the analyzer housing for storing and providing information characterizing performance parameters of the analyzer.

Respiratory gas analyzer

Growing community of inventors

Santa Clara, CA, United States of America

Davood Khalili