Analog Capacitor Integration Challenges

This paper discusses the challenges of making a MIM capacitor using a standard back end of line metal stack and a single additional mask. This required development of a capacitor dielectric would also serve as an antireflective coating for patterning 0.25 m metal interconnect lines or smaller. The paper also focuses on the characteristics of the analog capacitors. By improving this dual purpose oxide/SiON/oxide sandwich dielectric layer with special reflectivity properties, this novel integration forms a capacitor which possesses a combination of good voltage linearity or voltage coefficient, low dispersive behavior and hysteresis, and finally excellent matching with low leakage.