Wafer bonding method

Abstract

The invention relates to a wafer bonding method. The method comprises the following steps: providing a first wafer and a second wafer, wherein a first silicon oxide layer is arranged on the surface ofthe first wafer, and a second silicon oxide layer is arranged on the surface of the second wafer; exposing the first silicon oxide layer and the second silicon oxide layer to ultraviolet light so that at least a part of Si-O bonds in the first silicon oxide layer and the second silicon dioxide layer is broken; and carrying out bonding processing on the first wafer and the second wafer. The schemein the invention facilitates reduction of physical damage to the silicon oxide layers, the semiconductor substrate and the device, effectively protects the quality of image sensors and facilitates reduction of the production cost.

Description

technical field [0001] The invention relates to the technical field of semiconductor manufacturing, in particular to a wafer bonding method. Background technique [0002] The image sensor is the core component of the camera equipment, which realizes the image capture function by converting the optical signal into an electrical signal. Taking Complementary Metal Oxide Semiconductor Image Sensors (CMOS Image Sensors, CIS) devices as an example, due to their advantages of low power consumption and high signal-to-noise ratio, they are widely used in various fields. [0003] Taking Back-side Illumination (BSI) CIS as an example, in the existing manufacturing process, a device wafer is formed first, and logic devices, pixel devices and metal interconnection structures are formed in the device wafer, and then the bearing The front of the wafer is bonded to the front of the device wafer, and then the back of the device wafer is thinned, and the subsequent process of forming a CIS o...

AI Technical Summary

Problems solved by technology

[0005] However, in the prior art, the step of activating the silicon oxide layer is to break the Si-O bond in the silicon oxide layer by bombarding the silicon oxide layer with plasma, which is easy to cause physical damage to the silicon oxide layer, and then easily damages the silicon oxide layer. Semiconductor substrates and devices covered by a silicon oxide layer will seriously affect the quality of image sensors

In addition, due to the need to add additional equipment to generate plasma, such as the use of radio frequency (RF) systems, the cost increases, and the plasma reaction chamber requires a vacuum environment, resulting in more complex reaction devices and higher production costs

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