Si/Glass激光键合的仿真及实验研究

对Si/Glass激光键合进行了有限元仿真,自主设计激光键合系统并进行了Si/Glass激光键合实验研究、测试与表征。以Si/Glass激光键合的二维传热解析模型为理论基础,应用有限元软件ANSYS仿真了激光功率20～48W时激光键合的三维温度场、键合熔融深度,并预测键合阈值功率为28 W。自主设计激光键合系统及实验方案,采用光斑直径150μm、功率30W的Nd:YAG连续激光实现了Si/Glass的良好激光键合。测试结果表明,激光键合强度最高为阳极键合的5.2倍,激光键合腔体气密性测试泄漏率平均值约9.29×10-9 Pa.m3/s,与阳极键合处于同一数量级。采用能谱分析(EDS)线扫描Si/Glass激光键合的界面材料成分,发现键合界面形成过渡层,激光功率30W时过渡层厚度9μm,与仿真结果吻合。

Numerical and Experimental Investigation of Laser Bonding Silicon and Glass

This paper investigates laser bonding of silicon and Pyrex7740 glass by finite element method (FEM) simulation, self-design of apparatus and experimental research, test and characterization of bonding results. Based on a theoretical heat transfer two-dimensional (2D) model, a three-dimensional (3D) numerical simulation of laser bonding silicon and glass with laser power 20~48 W is conducted using ANSYS FEM softwave. Simulation results include temperature field and melted bonding depth which predicts the bonding threshold power is 28 W. A laser bonding apparatus with laser spot diameter of 150 μm and laser power of 30 W is designed to achieve good bonding. Shear force test shows that the bonding strength is 5.2 times of that of anodic bonding, while helium leak test on hermeticity of bonding samples observes average leakage rate of about 9.29×10-9 Pa·m3/s, which is the same order of magnitude as anodic bonding. From energy dispersive spectroscopy (EDS) line scanning laser bonded Si/glass interface cross section, the thickness of transition layer is 9 μm under 30 W laser, which agrees with the simulation results.