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According to the heat conduction equation, thermoelastic equation and boundary conditions of finite, using the finite
element method(FEM), established the three-dimensional finite element calculation model of thermal elastic ,numerical
simulation the transient temperature field and stress field distribution of the single crystal silicon materials by the
pulsing laser irradiation, and analytic solution the temperature distribution and stress distribution of laser irradiation on
the silicon material , and analyzes the different parameters such as laser energy, pulse width, pulse number influence on
temperature and stress, and the intrinsic damage mechanism of pulsed laser irradiation on silicon were studied. The
results show that the silicon material is mainly in hot melt under the action of ablation damage.According to the
irradiation of different energy and different pulse laser ,we can obtain the center temperature distribution, then get the
law of the change of temperature with the variation of laser energy and pulse width in silicon material; according to the
principal stress and shear stress distribution in 110 direction with different energy and different pulse, we can get the
law of the change of stress distribution with the variation of laser energy and pulse width ;according to the principal
stress distribution of single pulse and pulse train in 110 direction, we can get the law of the change of stress with pulse
numbers in silicon.When power density of laser on optical material surface (or energy density) is the damage threshold,
the optical material surface will form a spontaneous, periodic, and permanent surface ripple, it is called periodic surface
structure laser induced (LIPSS).It is the condensed optical field of work to generate low dimensional quantum
structures by laser irradiation on Si samples. The pioneering work of research and development and application of low
dimensional quantum system has important academic value.The result of this paper provides theoretical foundation not
only for research of theories of Si and substrate thermal stress damage and its numerical simulation under laser
radiation but also for pulse laser technology and widening its application scope.
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