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Thermal stresses are an important consideration in production
processes involving large temperature changes. Recently, Thermal
stresses have also become significant in semiconductors related
to wafers. To calculate the thermal stresses, we analysis four
kinds of boundary conditions. This article investigates the
thermal stress in a 8 inch wafer with its surfaces subjected to
heat radiation. In order to obtain the solution of the governing
equation, which is a partial differential equation, the
following procedures of analysis are used. 1. Normalize the
governing partial differential equation of temperature
subject to appropriate initial and boundary conditions.
Use finite-difference method to transform the governing
equation, initial and boundary conditions. 2. Normalize
the governing partial differential equation of stress
subject to appropriate initial and boundary conditions.
3. Substitute the temperature distribution into the
governing equation of thermal stresses. Then use Simpson，
s method to obtain the thermal stress distribution as a
function of time and position of the wafer.
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