Wafer bonding method and wafer bonding equipment

Abstract

The invention provides a wafer bonding method and wafer bonding equipment, and the method comprises the steps: enabling an electrostatic adsorption chuck to adsorb an upper wafer through electrostatic adsorption force, enabling a lower wafer to be fixed on a lower chuck, and enabling the upper wafer to be aligned with the lower wafer; pressing an ejector pin of the electrostatic adsorption chuck down the central area of the upper wafer, so that the upper wafer bends downwards and is in contact with the central area of the lower wafer; and adjusting the size of the electrostatic adsorption force, so that the upper wafer is gradually separated from the electrostatic adsorption chuck under the action of the gravity and the electrostatic adsorption force and is bonded with the lower wafer. An upper wafer is adsorbed through an electrostatic adsorption chuck, and in the process that the upper wafer falls and is bonded with a lower wafer, the upper wafer is gradually separated from the electrostatic adsorption chuck under the action of the gravity and the electrostatic adsorption force by adjusting the size of the electrostatic adsorption force, so that the process is controllable in the falling process of the upper wafer, the extension of bonding waves from the center to the periphery is not influenced, and wafer bonding is completed; and meanwhile, distortion of the wafer caused by a vacuum chuck vacuum adsorption mode is reduced.

Description

technical field [0001] The invention belongs to the technical field of integrated circuit manufacturing, and in particular relates to a wafer bonding method and wafer bonding equipment. Background technique [0002] With the continuous development of semiconductor technology, wafer bonding technology has been widely used. Bonding two or more wafers can effectively increase the number of devices per unit area. [0003] Such as figure 1 and figure 2 As shown, in the conventional bonding process, the upper chuck 04 is a vacuum chuck that absorbs the upper wafer 03 by vacuum, and the lower wafer 02 is fixed on the lower chuck 01 . After the upper wafer 03 and the lower wafer 02 are aligned, the thimble (Piston) 05 located in the central area of ​​the upper chuck 04 presses down on the upper wafer 03, causing the upper wafer 03 to bend downward and then move After reaching a certain distance, the central vacuum belt of the upper wafer 03 starts to release the vacuum, and the ...

AI Technical Summary

Problems solved by technology

In addition, the drastic change of force will cause the wear of the vacuum belt and affect the service life

[0008] (4) The upper wafer 03 falls by gravity, and the falling process is uncontrolled. The bonding wave expands from the center to the surroundings to complete the wafer bonding. The falling of the edge area will affect the expansion of the bonding wave to the surroundings, resulting in large edge distortion

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