Evaluation of Silicon Nitride MIM Capacitors for MMIC Applications

Abstract

With the rapid development and huge requirements of wireless communication systems, microwave-monolithic Integrated circuits (MMIC) with high performance and reliability have become very popular and been developed rapidly. The nitride quality and the reliability of the metal-insulator-metal (MIM) capacitor can be also researched based on time-dependent dielectric breakdown (TDDB) theory. In this paper, the various Si3N4 capacitors having different area sizes, aspect ratios and corners were designed with respect to nitride quality and lifetime evaluation. All of MIM capacitors used in this study are manufactured using a special reliability mask, and the test structures include various sizes of capacitors ranging from 10Kμm2 to 250Kμm2 as well as capacitor corner check. The ramp voltage and the constant voltage tests are destructive oftentimes to identify the cause of dielectric failure. Combining these breakdown marks with an optical microscope inspection and cross section check of the 10Kμm2 capacitors as well as corner-structure check are reported in this paper. That can make the identification and classification of dielectric breakdown mechanisms. When the capacitor size is larger than that of 65K-um2, the factor of failure acceleration raises significantly.