Predicting plastic and fracture properties of silicon oxycarbide thin films using extended finite element method

The mechanical reliability of SiCO thin films is a key factor for its applications, however, the fracture properties of SiCO films systems have not yet been sufficiently explored. In this work, the plastic behavior and fracture properties of SiCO films are evaluated and predicted by simulating nano-indentation by extended finite elements method. To improve the accuracy of the model, an interfacial layer is added between SiCO thin film and Si substrate. Based on the improved model, the calculated load-displacement curves, Young's modulus and hardness consist nicely with available experimental data in all the indentation stages, and the mechanical behavior relating to interfacial delamination is successfully captured. The plastic properties of the films are obtained by calculating stress-strain relationship, yield strength and strength coefficient. Moreover, the crack propagation paths for different SiCO films and the calculated energy release rates are comparable to the experimental results. (C) 2019 Elsevier B.V. All rights reserved.