環境對二氧化矽薄膜性質與接合強度之研究

Silicon dioxide (SiO2) is widely applied as dielectric layer between conductive wires in semiconductor process. The thickness of dielectric layer reach to micro-scale in advanced packaging process. Due to micro-scale SiO2 bonding. SiO2 thin film suffers from tensile stress and leads to forming cracks. For the purpose of preventing cracks, the stress of thin film is preferred to be compressive stress by absorbing moisture. In this study, plasma enhanced chemical vapor deposition (PECVD) is used to prepare SiO2 thin film samples. These samples will be placed in Programmable Temp. & Humi. Chamber to absorb moisture for the sake of changing stress. The relationship between absorbing time and functional group of SiO2 film will be characterized by X-ray photoelectron spectroscopy (XPS). The SiO2 thin film samples will be bonded together and be mounted in epoxy. After grinding and polishing to obtain clear cross-section. Cold field emission-scanning electron microscope (CFE-SEM) will be used to observe surface morphology, microstructure, and the fracture surface of SiO2 samples after bonding. Mechanical strength will be tested by using bond tester to quantify the performance of bonding.