RF characterization and design of multi-TSV with embedded capacitor

Abstract

This paper presents RF characterization and design of multi-TSV with embedded capacitor up to 10GHz. The capacitor is embedded around the TSV structure prior to Cu filling to utilize the vertical dimension, and thus improves the capacitance density and silicon area utilization. Here, the capacitance response with respect to variations in structural dimension such as TSV height, diameter, metallization and dielectric thickness are systematically studied. The results show that the increase in the thickness of Cu (electrode metal) continuously improves the Q-factor without any significant degradation in capacitance, which enables these capacitors to be used at higher frequency. Also, the thickness of TiN (used as diffusion barrier layer on both side of Cu electrode) neither affects the Q-factor nor the capacitance.