AVS 46th International Symposium
    Manufacturing Science and Technology Group Wednesday Sessions
       Session MS-WeM

Paper MS-WeM2
Broad Band RF Based Sensing and Control of Reactive Ion Etching

Wednesday, October 27, 1999, 8:40 am, Room 611

Session: Metrology I
Presenter: C. Garvin, The University of Michigan
Authors: C. Garvin, The University of Michigan
J.W. Grizzle, The University of Michigan
Correspondent: Click to Email
This talk will present continued advances in the development of an in-situ RF sensing system for plasma assisted microelectronics processing. RF sensing has long been considered a potentially valuable diagnostic. However, despite much effort, results to date have been limited and mostly qualitative. Our past work has indicated that these limitations are due to inherently poor sensitivity in passive RF sensing. In addition, we have shown significantly better sensitivity to process conditions using a novel multi parameter variation of microwave spectroscopy, referred to as Broad Band RF. On a research reactor (GEC) and for simple chemistries, a non commercially viable version of the broad band probe was shown to be substantially better than standard RF sensing approaches at detecting process setpoints.@footnote 1@ Recently, we have developed a commercially viable non-contacting version of our broad band sensor, and have implemented it on a Lam 9400. The sensor has been used to develop an etch rate model for polysilicon in a Cl2/HBr chemistry.@footnote 2@ In this talk, we will present continued progress towards process control with the broad band sensor. Initial results indicate the broad band sensor is capable of endpointing performance that is at least as good as standard photo diode based OES methods. We will present further advances in a broad band etch rate model. Initial data indicates that an oxide etch rate model is at least as good as the polysilicon etch rate model already presented. Finally, we will investigate physically dominated and chemically dominated etch regimes in more detail. We will present results of initial work in these areas. @FootnoteText@ @footnote 1@ Garvin, C. Grimard, D. S., and Grizzle, J. W. "Advances in Broadband RF Sensing for Real-time Control of Plasma-Based Semiconductor Processing" JVSTA, Jul/Aug 1999 @footnote 2@ Garvin, C. Bilén, S. G. Stutzman, B. S. and Grizzle, J. W. "Implementing Broad Band RF Sensing on a Lam 9400 Reactor", The Electrochemical Society 195@super th@ Meeting, May 2-6 1999