Experimental study of charging processes on unpatterned oxide-coated Si wafers in an ECR etcher

Summary form only given, as follows. During plasma processing, used in the fabrication of integrated circuits, oxide surface charging is becoming more of a concern due to its increased damage potential. In this work, plasma induced charging mechanisms onto the surface of oxide-covered unpatterned 4" Si wafers exposed to non-uniform O/sub 2/ and Ar electron-cyclotron-resonance (ECR) plasma are investigated. Wafers covered with a 1000 /spl Aring/ oxide layer were exposed to the ECR plasma under non-uniform etching conditions, and the induced surface charge was mapped on the wafers using the Contact Potential Difference (CPD) technique. During processing, plasma parameters (floating potential, plasma potential, electron temperature, and ion density) were monitored in the bulk of the plasma using Langmuir probes as well as on the surface of the wafers (i.e. surface potential) along with the same magnetic field lines using special wafer probes.