Temperature distributions produced in semiconductors by a scanning elliptical or circular cw laser beam

Abstract
Temperature profiles induced by a cw laser beam in a semiconductor are calculated. The calculation is done for an elliptical scanning beam and covers a wide range of experimental conditions. The limiting case of a circular beam is also studied. This calculation is developed in the particular cases of silicon and gallium arsenide, where the temperature dependence of the thermal conductivity has been taken into consideration. Using a cylindrical lens to produce an elliptical beam with an aspect ratio of 20, a 1‐mm‐wide area of an ion‐implanted silicon wafer was annealed in a single scan. The experimental data are consistent with the extrapolation of solid‐phase epitaxial regrowth rates to the calculated laser‐induced temperatures.