薄膜微电极在热键合过程中的断裂行为研究

Research of Fracture Behaviors of Microelectrode During Thermal Bonding

为了实现真正意义上的芯片实验室,金属微电极正在成为微流控芯片的重要组成部分。针对铜薄膜微电极在热键合过程中的断裂问题,利用断口分析技术研究了其断裂行为。分析了多种制备断口的方法并利用精密的自动砂轮划片机制备出了理想的断口试样,对断口试样进行宏观分析,判定该断裂是由于剪切引起的韧性断裂,利用扫描电子显微镜进行微观分析,推断出电极在热键合过程中既承受剪切力又承受拉应力,判定铜薄膜微电极在PMMA芯片热键合过程中的断裂机理是一种典型的韧窝式韧性断裂,铜薄膜微电极的断裂是由较高的热键合温度引起的。

To achieve the purpose of lab-on-a-chip device, the integrated metal microelectrode has been becoming one of the essential compositions of microfluidic chips. To solve this problem, it has studied the fravture behavior of the integrated metal microelectrode by the technique of fractography analysis. Multiple preparation method of fracture is discussed and the ideal fracture specimens are prepared with sophisticated automatic wheel dicing mechanism believing that the fracture is due to shear cut ductile fracture. Fracture of specimen shows typical dimple structure, believes that the electrode has loaded shear stress and tensile stress during the thermal bonding process, the fracture mechanism of the copper film microelectrode is typical dimple ductile fracture, and the higher thermal bonding temperature led to the fracture is believed.