Luxtron Corporation

Xinix, Inc.

Steven C Leach

Herbert E Litvak

Edward G Rodgers

Eric L Bogatin

Mariste A Thomson

Edward G Rogers

Raymond J Cadet

Sing-wing Hui

Hung-Nan Chao

Jewett W Fowler

An improved method for minimizing interferences from random noise and correlated fluctuations which obscure electrical signals converted from optical emissions. In particular, an improved method for the removal of interferences from optical emission signals during endpoint determination in dry etching processes for the fabrication of micro-electronic devices which derives information in the presence of random noise, correlated fluctuations and periodic modulations of the plasma by maximizing the signal to random noise ratio and minimizing the obscuring effects of correlated fluctuation.

Interference removal

An improved method for minimizing interferences from random noise and correlated fluctuations which obscure electrical signals converted from optical emissions. In particular, an improved method for the removal of interferences from optical emission signals during endpoint determination in dry etching processes for the fabrication of microelectronic devices which derives information in the presence of random noise, correlated fluctuations and periodic modulations of the plasma by maximizing the signal to random noise ratio and minimizing the obscuring effects of correlated fluctuation.

Methods and apparatus for enhancing the accuracy for detecting the endpoint of certain operations (such as etching, photoresist development or chemical reaction) in the processing of materials which results in a change in the reflectivity or refractive index of the material are provided. The methods decrease the sensitivity of endpoint detection to high frequency noise and periodic oscillations. The methods also allow accurate calculation of overprocessing time and real-time viewing of data by the user.

Method of endpoint detection and structure therefor

A sensor board for use with an endpoint controller which monitors light intensity is provided. The sensor board can provide a dynamic range of up to five million because a constant current driver and phase sensitive detector help eliminate noise from the detected signal. The sensor board can also subtract a DC voltage offset from the detected signal and amplify the difference to provide increased resolution of small changes in the detected signal.

Growing community of inventors

Santa Clara, CA, United States of America

Steven C Leach