纳秒级脉冲激光诱导Zn掺杂过程中GaN/Al_2O_3材料的温度分布及热形变解析分析

Analytical calculation of temperature distribution and thermal deformation during doping of Zn in GaN/Al_2O_3 material induced by nanosecond pulse-width laser

分析了纳秒级脉冲激光作用下GaN的激光诱导Zn的掺杂过程.利用简化的一维模型,给出一种比较直观的脉冲激光辐照下GaN/Al2O3材料温度分布的解析形式,得到了GaN材料表面温度与激光辐照时间的关系以及材料形变与深度的关系.在激光脉冲作用时,GaN材料表面的温度与辐照时间的平方根成正比.脉冲过后,材料温度分布梯度和热形变分布随深度发生变化,接近表面的温度梯度最大,热形变量也最大.而在连续脉冲作用时表面的温度呈锯齿状不断升高.

The process of doping of Zn into GaN induced by nanosecond pulse laser is analyzed in this paper. An analytical formula of temperature distribution in GaN material irradiated by pulsed laser is presented using one-dimensional model. The relation of surface temperature versus irradiation time and thermal deformation versus depth are obtained. The results show that the surface temperature is in proportion to the square root of irradiation time. The distributions of temperature and thermal deformation in the material are also obtained. The temperature gradiant and the thermal deformation are all highest near the surface. However, the temperature of surface increases in a saw-tooth manner when the material is irradiated continuously by pulseed laser.