Kumar Dhruva, Meena Rajesh Kumar, Ghadai Ranjan Kumar
Department of Mechanical Engineering, Sikkim Manipal Institute of Technology, Sikkim Manipal University, Majitar, Sikkim, 737136, India.
Department of Industrial Engineering, University of Trento, Via Sommarive 9, 38123 , Trento, Italy.
Sci Rep. 2025 Aug 28;15(1):31759. doi: 10.1038/s41598-025-15659-5.
In this work, SiCN thin films were deposited on p-Si (100) substrate using a thermal Chemical Vapor Deposition (CVD) process. The mechanical behavior of the thin film was characterized using the nanoindentation technique, where the load was varied from 1 to 4 mN, to understand the influence of load variation on the load-displacement response. Additionally, an experimentally validated FE model, incorporating an elast-plastic material response of the thin film, was developed to understand localized stress distribution and fracture behavior. The fracture behavior is examined through two modes: (a) cracking and interfacial delamination during the nano-indentation test and (b) the peel test. The FE model revealed that in the case of the weak cohesive interface between SiCN and Si, the interfacial failure initiates at a critical displacement of ∼ 110 nm. During the peel test, it was observed that the critical fracture energy of the interface plays a significant role in the interface debonding. These finding highlights the strong dependence of the mechanical integrity of the SiCN thin film on the applied load.
在本工作中，采用热化学气相沉积（CVD）工艺在p-Si（100）衬底上沉积了SiCN薄膜。使用纳米压痕技术对薄膜的力学行为进行了表征，其中载荷在1至4 mN之间变化，以了解载荷变化对载荷-位移响应的影响。此外，还开发了一个经过实验验证的有限元模型，该模型考虑了薄膜的弹塑性材料响应，以了解局部应力分布和断裂行为。通过两种模式研究断裂行为：（a）纳米压痕试验期间的开裂和界面分层，以及（b）剥离试验。有限元模型表明，在SiCN和Si之间内聚界面较弱的情况下，界面失效在约110 nm的临界位移处开始。在剥离试验中，观察到界面的临界断裂能在界面脱粘中起重要作用。这些发现突出了SiCN薄膜力学完整性对所施加载荷的强烈依赖性。
