MIM capacitor and manufacturing method thereof

Abstract

The invention provides an MIM capacitor and a manufacturing method thereof. The manufacturing method comprises the steps of providing a semiconductor substrate, and forming a first metal layer on thesemiconductor substrate; forming an anti-reflection layer on the first metal layer; photoetching and etching the first metal layer and the anti-reflection layer to define an MIM capacitor region, wherein the first metal layer in the MIM capacitor region serves as a lower pole plate of the MIM capacitor, and the anti-reflection layer in the MIM capacitor region serves as a dielectric layer of the MIM capacitor; and forming an upper pole plate of the MIM capacitor on the anti-reflection layer in the MIM capacitor region. According to the manufacturing method provided by the invention, the anti-reflection layer reserved in the etched area is used as a dielectric layer of the capacitor at the same time, the etched area is continuously filled with metal to serve as the upper pole plate, an additional capacitor dielectric layer does not need to be manufactured, an additional photoetching process is not needed for defining the upper pole plate area any more, and the photoetching and etching frequency is reduced, so that the process cost is reduced, and the process period is shortened.

Description

technical field [0001] The invention relates to the technical field of semiconductors, in particular to a MIM capacitor and a manufacturing method thereof. Background technique [0002] Capacitors are widely used in semiconductor integrated circuits as charge storage, coupling and filtering devices. Among existing integrated circuit capacitors, metal-insulator-metal (MIM, Metal-Isolation-Metal) capacitors have gradually become the mainstream in radio frequency integrated circuits, especially in the mixing / radio frequency CMOS process. The reason is that it is usually made in the metal interconnection layer, which is compatible with the integrated circuit process and has a long distance from the substrate, which can overcome the large parasitic capacitance of many other types of capacitors and the degradation of device performance with increasing frequency. Significant downsides. [0003] MIM capacitors are usually located on the upper layer of a multilayer device structure...

AI Technical Summary

Problems solved by technology

More process steps lead to increased production costs and longer production cycles

Images