Wafer bonding device and method

Abstract

The invention relates to the technical field of semiconductor manufacturing and particularly relates to a wafer bonding device and method. The device includes a first fixing device which is capable of moving only in the X and Y axis directions and is used for fixing a to-be-bonded first wafer on which a first calibration sign is arranged, a reference sign arranged on the first fixing device, a second fixing device which is capable of moving in the X, Y and X axis directions and is opposite to the first fixing device, a rotation device which is arranged at a surface of the second fixing device facing the first fixing device and is used for fixing a to-be-bonded second wafer on which a second calibration sign is arranged, an image acquisition device which is oppositely arranged, can synchronously move along X, Y and Z axes and is used for acquiring the first calibration sign and the second calibration sign, and a reference sign acquisition device used for reading the reference sign. The device is advantaged in that the first calibration sign and the second calibration sign can be clearly acquired by the image acquisition device, and wafer bonding accuracy is improved.

Description

technical field [0001] The invention relates to the technical field of semiconductor manufacturing, in particular to a wafer bonding device and method, so as to improve the precision of wafer bonding. Background technique [0002] Wafer alignment is the most critical factor affecting the bonding accuracy in the wafer bonding process. Wafer alignment is mainly composed of the mechanical movement of the chuck (Table) that fixes the wafer and reading the alignment mark (Mark) on the wafer. ) lens to obtain wafer coordinates together to achieve. [0003] The two bonded wafers are divided into upper wafer and lower wafer, and the lenses for reading the alignment marks of the two wafers are divided into independent type and integrated type. The stand-alone type is to read the lenses of the upper wafer and the lower wafer are independent of each other, and finally convert the mark coordinates acquired by the two lenses into a coordinate system to calculate the relative position of...

AI Technical Summary

Problems solved by technology

[0004] After the existing technology, the upper and lower lenses are calibrated to determine the distance between the upper and lower lenses. It is manually adjusted to read the calibration mark of the same wafer, which can be read in the depth of field of the lens, and there is an error compared with the standard focal length; resulting in When the integrated lens reads the alignment mark of the lower wafer most clearly, it often reads the alignment mark of the upper wafer in the back and is not clear

Moreover, since the upper chuck cannot move vertically in the Z-axis direction, the lens and the upper chuck cannot move relative to each other when reading the alignment mark of the upper wafer. The alignment marks are not clear

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