Manufacturing and reliability improvements in metal-oxide-metal capacitors-MOMCAPs

Abstract

Metal-oxide-metal capacitors (MOMCAPs) have historically demonstrated less than optimal leakage and breakdown characteristics and yields. Additionally, the C/sub pk/ for capacitance is low. Any previous work done to improve the dielectric uniformity has resulted in further degradation of the capacitor characteristics. In this paper, we show that the parametric and reliability characteristics are very dependent on the bottom plate material. Our standard Ti bottom plate interacts with the capacitor dielectric, resulting in degraded performance. That interaction renders a more uniform dielectric film unusable. We have developed a MOMCAP using TiW as the bottom plate electrode, which minimizes those interactions and improves the capacitor characteristics.