Wafer marking monitoring method and laser marking machine alignment position determination method

Abstract

The invention provides a wafer label monitoring method and a laser number etching machine bench alignment position judgment method. The monitoring method comprises the steps: in a wafer label horizontal plane, scanning wafer labels in the two cross directions to obtain two groups of waveform signals in the corresponding directions; measuring the diameter length of the same wafer label in the two groups of waveform signals; judging whether a difference value of absolute values of the diameter lengths in the two groups of waveform signals can meet a preset error range; when the difference valueof the absolute values of the diameter lengths in the two groups of waveform signals is in the preset error range, judging that the shapes of the wafer labels are not abnormal; when the value of the absolute values of the diameter lengths in the two groups of waveform signals is not in the preset error range, judging that the shapes of the wafer labels are abnormal. The wafer label monitoring method disclosed by the invention can monitor whether the shapes and the light path directions of the wafer labels are abnormal.

Description

technical field [0001] The invention relates to the technical field of semiconductor manufacturing, in particular to a method for monitoring wafer marks and a method for judging the alignment position of a laser marking machine. Background technique [0002] In the field of semiconductor manufacturing technology, one process requires simultaneous operation of multiple wafers, that is, each process in the semiconductor process processes wafers in batches. Multiple wafers in the same process are identical to each other, making it impossible to distinguish them. In practice, wafers can be distinguished by their placement positions, but when the placement positions of the wafers change for some reason, it will lead to confusion in identifying different wafers. In order to distinguish each wafer, a common practice in the prior art is to bombard the wafer with a laser to form a wafer mark on the surface of the wafer. To distinguish between individual wafers, different wafers are...

AI Technical Summary

Problems solved by technology

The monitoring method of the wafer mark mainly scans the waveform signal of the wafer mark, and measures the peak value and valley value of the corresponding waveform signal of the wafer mark, so as to monitor the laser energy, but it is impossible to determine whether the shape of the wafer mark and the orientation of the optical path are abnormal

When using laser bombardment to form wafer marks on the wafer surface, as the laser marking machine ages, the machine hardware (mainly refers to the laser diode) is replaced more and more frequently. The existing testing machine projects in the industry have already Unable to detect the abnormality of the wafer mark, which adds a lot of difficulty to the operator's daily maintenance work

In addition, the abnormality of the shape of the wafer mark and the orientation of the optical path will also lead to the deterioration of the stability of the laser marking machine

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