Semiconductor device, metal-insulator-metal capacitor and method for manufacturing same

Abstract

The invention provides a semiconductor device, a metal-insulator-metal (MIM) capacitor and a method for manufacturing the same, wherein the method comprises the following steps: depositing a first metal layer on a semiconductor substrate and patterning the metal layer; depositing a passivation layer on the first metal layer and forming a connecting line hole thereon by etching; depositing a dielectric layer on the surfaces of the passivation layer and the connecting line hole and etching part of the dielectric layer; covering and depositing a second metal layer on the surfaces of the dielectric layer and the passivation layer; and using the first metal layer as a lower electrode plate and the second metal layer as an upper electrode plate. The MIM capacitor combines the upper electrode plate metal layer with a metal interconnection layer, reduces the space occupied in the semiconductor device, avoids influencing the photosensitive property of edge pixels in a pixel array, and can achieve the aim of reducing lateral light crosstalk by arranging the position and the number of the connecting line hole reasonably.

Description

technical field [0001] The present application relates to the field of CMOS process manufacturing, and in particular to a semiconductor device, a metal-insulator-metal (Metal-Insulator-Metal, MIM) capacitor and a manufacturing method thereof. Background technique [0002] A CMOS image sensor (CIS), which is a semiconductor device that converts an optical image from an optical signal to an electrical signal, employs a switching mode to sequentially detect pixel outputs by providing a predetermined number of MOS transistors to each pixel. The key to determining the image quality of a CMOS image sensor is dark current and dynamic range. [0003] like figure 1 A pixel unit circuit of a four-tube structure CMOS image sensor is shown. It mainly includes a photodetector PDD, a transmission tube T1, a reset tube T2, a source follower T3, and a selection tube T4. The photodetector PDD includes a photodiode that generates charges from light energy and integrates the charges at poin...

AI Technical Summary

Problems solved by technology

[0012] The technical problem to be solved by the present invention is that the MIM capacitor manufactured by the existing CMOS process takes up a large space in the CMOS image sensor, and the thickness of the metal layer is too high, which will cause photosensitive loss to the pixels at the edge of the pixel array.

Images