AVS 53rd International Symposium
    Plasma Science and Technology Friday Sessions
       Session PS2-FrM

Paper PS2-FrM1
Substrate Temperature Sensor Measurements and Analysis in an Inductively Coupled Plasma

Friday, November 17, 2006, 8:00 am, Room 2011

Session: Diagnostics
Presenter: M.J. Titus, University of California at Berkeley
Authors: C.C. Hsu, University of California at Berkeley
M.J. Titus, University of California at Berkeley
D.B. Graves, University of California at Berkeley
Correspondent: Click to Email
The OnWafer commercial plasma sensor system consists of sensors embedded on a thin-film battery-powered Si wafer that can enter and exit commercial plasma tools via conventional wafer-handling robotic transfer. An on-board electronics module coupled with wireless communication allows storage of process data followed by infrared uploading post-process. While this is a proven avenue for plasma process development and quasi-real time process control applications, full interpretation of sensor measurements in terms of intrinsic plasma characteristics requires validation. This talk describes the use of the OnWafer system in a university-built inductively coupled plasma (ICP) tool, equipped with a variety of plasma sensors. We describe results from a combined plasma and wafer model and compare the model predictions to both sensor measurements and plasma measurements. Measurements of wafer temperature transients (using PlasmaTemp@super TM@) are compared to a wafer and plasma model. A combination of radially-resolved Langmuir probe measurements and an ICP model is used to obtain the radial energy flux profile from the plasma to the wafer surface. Model predictions and measured transient wafer temperature profiles agree near-quantitatively, if details of the wafer and chuck characteristics are properly included. The model and measurements must include the effects of heat release due to ion-electron recombination and radical recombination at the wafer surface.