A mim capacitor and its manufacturing method

Abstract

The present invention provides a MIM capacitor and a manufacturing method thereof, the manufacturing method comprising: providing a semiconductor substrate, forming a first metal layer on the semiconductor substrate; forming an anti-reflection layer on the first metal layer; Engraving and etching the first metal layer and the anti-reflection layer to define a MIM capacitor area, the first metal layer in the MIM capacitor area serves as the lower plate of the MIM capacitor, and in the MIM capacitor area The anti-reflection layer is used as the dielectric layer of the MIM capacitor; the upper plate of the MIM capacitor is formed on the anti-reflection layer in the region of the MIM capacitor. In the manufacturing method of the present invention, the anti-reflection layer retained in the etched area is used as the dielectric layer of the capacitor at the same time, and the metal is continued to be filled in the etched area as the upper plate, and no additional dielectric layer of the capacitor is required. , and no additional photolithography process is required to define the upper plate area, reducing the number of photolithography and etching, thereby reducing the process cost and shortening the process cycle.

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...

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Problems solved by technology

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

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