ELASTO-VISCOPLASTIC WAVE THERMOMETRY FOR SINGLE CRYSTALLINE SILICON PROCESSING Academic Article uri icon

abstract

  • Laser-induced stress wave thermometry (LISWT) is a non-contact thermal diagnostic technique for the rapid thermal processing (RTP) of silicon wafers using laser-generated, ultrasonic, dispersive stress waves. The required knowledge base for establishing LISWT as a viable alternative to current pyrometric technology for temperature measurement up to 1000C with 1C resolution is presented. A 3D elasto-viscoplastic wave model is developed for describing wave behaviors from being elastic to viscoplastic subject to the RTP annealing temperature ranging from room temperature to exceeding 1000C. The model is a system of nine coupled first-order hyperbolic equations formulated based on the kinematics of elasto-plastic deformation, conversion of linear momentum and a temperature-dependent viscoplastic constitutive law for single crystalline silicon derived from the material models developed by HassenSumino and Tsai. The group velocity of the wave propagating in silicon wafer is a nonlinear function of temperature. As nonlinearity becomes prominent at high temperature for high frequency components, low frequency components are preferably exploited to achieve the desired thermal resolution at high temperature.

published proceedings

  • INTERNATIONAL JOURNAL OF APPLIED MECHANICS

author list (cited authors)

  • Qi, X., Liu, L. i., Suh, C. S., & Chona, R.

citation count

  • 5

complete list of authors

  • Qi, Xuele||Liu, Li||Suh, C Steve||Chona, Ravi

publication date

  • December 2010