Special new pattern identification sign for testing film layer thickness in semiconductor device

Abstract

The present invention proposes one new kind of graphic recognition mark specially for testing the film thickness in semiconductor device, and the graphic recognition mark is one good comparison graph set on chip for graph recognition. The graphic recognition mark has two polygons or circles in the same geometric shape and different areas and superposed in centroid superposing mode. The polygons or circles are divided with diagonals or diameter line into several areas, of which the adjacent two are made of different materials and have different. For example, one of two adjacent areas is made of metal material, such as Al, Cu or Ag, while the other of other material, such as dielectric, oxide, nitride, etc. The two adjacent areas are constituted in different film layers and have different heights counted from the chip bottom layer.

Description

technical field [0001] The invention relates to a new pattern recognition mark, in particular to a new pattern recognition mark specially used for testing the film thickness in semiconductor devices. Background technique [0002] In advanced factories, in order to obtain semiconductor devices with consistent quality, the thickness of the film layer in the semiconductor device under manufacture is usually tested by monitoring the actual process. To do this, it is first necessary to successfully identify the pattern to test the thickness of the film layer in the semiconductor device. This requires dedicated good contrast graphics. [0003] The general method now is to arbitrarily select a device pattern on the wafer as a test mark, and as the process steps continue, the pattern selected as the test mark also changes, and it is not accurate to use such a constantly changing pattern as a pattern identification mark. To test the thickness of film layers in semiconductor devices...

AI Technical Summary

Problems solved by technology

[0003] The general method now is to arbitrarily select a device pattern on the wafer as a test mark, and as the process steps continue, the pattern selected as the test mark also changes, and it is not accurate to use such a constantly changing pattern as a pattern identification mark. to test film thickness in semiconductor devices

[0004] With more and more transistors on a semiconductor chip, the composition of the chip becomes more and more complex, and it becomes more and more difficult to find a good mark pattern for pattern recognition

Mistakes in pattern recognition can lead to the inability to correctly test the film thickness in semiconductor devices, interrupt the process, prolong the process cycle, and even fail to obtain real process data

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