Salicide process using cmp for image sensor

Abstract

A self-aligned silicide (salicide) process is used to form a silicide for a CMOS image sensor consistent with a conventional CMOS image sensor process flow. An insulator layer is deposited over the pixel array of the image sensor. An organic layer is deposited over the insulator layer. A chemical mechanical polish (CMP) is performed to remove the organic over raised polysilicon structures. Using the organic layer as a mask, portions of the insulator layer are removed and a metal layer is deposited. The metal layer is annealed to form a metal silicide.

Description

technical field [0001] The present invention relates to an image sensor, and more particularly, the present invention relates to an image sensor processed by a self-aligned metal silicide (salicide) process. Background technique [0002] Image sensors have become ubiquitous, and they are widely used in digital cameras, cellular phones, security cameras, medical equipment, automobiles, and other applications. The technology of manufacturing image sensors, especially CMOS (Complementary Metal Oxide Semiconductor) image sensors continues to develop rapidly. For example, the requirements of high resolution and low power consumption promote the further miniaturization and integration of image sensors. [0003] With further integration, an important feature of an image sensor is the ability to quickly read signals from the pixel array. Pixel arrays containing more than five million individual pixels are not uncommon. Many image sensors use a salicide process to improve the spee...

AI Technical Summary

Problems solved by technology

In all of these cases, the problem is that the current manufacturing process does not have a process margin to ensure that when the organic film 201 is completely removed from the polysilicon interconnect 113, the organic film 201 remains on the photodiode.

At this point, the problem with the prior art is very obvious

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