Wafer thickness measuring device and grinding machine

Abstract

The invention discloses a wafer thickness measuring device and a grinding machine table. The measuring device comprises a main structure, a lifting hanging structure and an optical sensor assembly; the hanging structure is mounted on the lower portion of the main structure, the lower portion of the main structure is arranged in a groove of the hanging structure in a sliding manner, a first fluid pipeline leading to the connecting position of the main structure and the hanging structure is arranged in the main structure and used for inflating first fluid to the groove so as to lift the hangingstructure, the main structure is provided with a first through hole which penetrates through the upper surface and the lower surface of the main structure and is used for containing the optical sensorassembly, a second through hole is formed in the position, below the first through hole, of the groove bottom of the hanging structure to enable a light path output by the optical sensor assembly topass through, and a second fluid pipeline is arranged in the hanging structure to achieve the aim that a cavity formed by the bottom face of the main structure, the bottom face of the optical sensor assembly, the groove inner face and the second through hole is filled with second fluid. Accuracy and precision of wafer thickness measuring can be effectively improved.

Description

technical field [0001] The invention relates to the technical field of wafer ultra-precision grinding, in particular to a wafer thickness measuring device and a grinding machine. Background technique [0002] At present, the semiconductor industry uses electronic circuits formed on the surface of semiconductor wafers to manufacture semiconductor chips. Before the wafer is divided into semiconductor chips, the wafer is thinned to a predetermined thickness by grinding the back surface opposite to the device surface on which the electronic circuit is formed by a grinding processing apparatus. Grinding on the back of the wafer can reduce the volume of the chip package, reduce the height of the package and mount, improve the thermal diffusion efficiency, electrical properties and mechanical properties of the chip, thereby reducing the amount of chip processing, and the thickness of the chip after the back is thinned can even reach the initial less than 5% of the thickness. [0...

AI Technical Summary

Problems solved by technology

During the grinding process, there will be water film, water droplets, particle pollutants, etc. on the surface of the wafer, which will change the optical path of optical measurement, bring interference to non-contact measurement, and affect measurement accuracy

To sum up, there are problems of inaccurate wafer thickness measurement and low precision in the prior art

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