Method for initiating a helium alarm particle detector in a dry etching system prior to initiation of the etching process

Abstract

A process for determining particles in a dry etching system, prior to performing the dry etching definition of a desired pattern, has been developed. The process features a two cycle, dry etching procedure, with the first cycle performed using a first set of dry etching conditions, not robust enough to result in etching of exposed material, but robust enough do allow the activation, and operation, of a backside helium alarm procedure, used to monitor particle count in the dry etching chamber, to be realized. If particle counts are acceptable a second cycle of the dry etching procedure, using a second set of dry etching conditions, is employed to define the desired pattern. If the particle counts observed via use of the backside helium alarm procedure during the non-etching, first cycle, are high, the dry etching procedure is interrupted. After cleanup of the dry etching chamber, the same samples, with a re-worked photoresist, are again subjected to the two cycle, dry etching procedure.