低压下激光剥离的研究

为了研究低压环境对激光剥离的影响,利用准分子激光剥离系统和真空腔对GaN/蓝宝石样品分别在低压下和常压下进行多脉冲激光照射,之后用台阶仪测量样品的分解深度,得知相比常压环境,低压下GaN分解深度在脉冲次数为10次、20次、30次时分别增加了为10.2%,19.0%,24.3%,之后结合GaN材料分解过程和脉冲激光照射GaN/蓝宝石结构过程进行理论分析得到相应低压和常压下的GaN材料的理论分解深度,得到与实验一致的趋势。证明了低压环境能提高激光剥离速率。

Study on laser lift-off of GaN material in low pressure

In order to study the effects of low-pressure environment on laser lift-off process, the experiment that a GaN/sapphire sample was irradiated by an excimer laser lift-off system in different pressure was carried out, and then the decomposition depth of the sample was measured with a profilometer. The results show that the decomposition depth of GaN in low pressure is increased by 10.2%, 19.0% and 24.3% which corresponds to the number of pulses of 10, 20 and 30. One-dimensional heat flow model of GaN/sapphire structure irradiated by laser was established. The temperature field in GaN was calculated and analyzed. The decomposition depth of GaN in different pressure was obtained. The theoretical calculation result is consistent with the experimental result. It indicates that the efficiency of laser lift-off in low pressure environment is higher than that in ordinary pressureenvironment.