Validated Methodology for Accurate Simultaneous Measurement of Elastic Modulus and CTE of BEOL Materials for Improved Advanced Package Performance Prediction

This work focuses on the development of a methodology that enables robust, simultaneous measurement of the elastic modulus and coefficient of thermal expansion (CTE) of thin films used in microelectronics packaging, with the goal of enabling improved reliability and performance prediction of microelectronic packages. Through the performance of in-situ temperature dependent film stress measurement of SiNx film deposited on glass substrates with widely varying CTEs, both the elastic modulus and CTE of SiNX film were determined simultaneously. This was achieved for varying SiNx thicknesses (125nm–2,000nm). Similar measurements were performed by nano-indentation measurement method, with both measurement methods yielding very comparable elastic modulus values for the different studied SiNx thicknesses.