Semiconductor Process Method

Abstract

The invention provides a semiconductor process method, comprising the steps of: 1) providing a background plate, and forming a rectangle on the background plate with positioning mark points; Oval wafer picture and positioning mark points; 3) Edit the picture to mark the positions corresponding to wafer edge notches and defects; 4) Find the wafer edge, defects, edge notches, and positioning mark points on the picture ; 5) transform the positioning mark point back to a rectangle with the same size as step 1); 6) transform the defects and edge gaps back to the position on the back of the original wafer, and reconstruct the depth distortion of the picture; 7) carry out mirror flipping on the wafer; 8) The front-side defect locations and the back-side defect locations of the wafer are overlaid to identify chips having at least one of the front-side defects and the back-side defects. The invention helps to accurately reflect the defects on the back side of the wafer to the front side of the wafer so as to accurately detect all defective chips.

Description

technical field [0001] The invention relates to the field of semiconductor chip manufacturing, in particular to a semiconductor process method. Background technique [0002] A final inspection of the wafer is usually performed before the wafer is diced to separate the wafer into individual chips, in which the chips exhibit poor reliability or poor reliability due to surface scratches, particle contamination, etc. For other defects, it is necessary to mark the defective chip, which is usually called an "ink pass die" process. Defects on either of the front and back surfaces of the wafer corresponding to the same chip need to be marked. Therefore, the backside defects of the wafer are reflected to the front side of the wafer, so as to determine all the defects based on the front and backside defects of the wafer The location of the defective chip is very important. In the prior art, the back of the wafer is usually photographed after the ink pass die is completed, and the po...

AI Technical Summary

Problems solved by technology

In the prior art, the backside of the wafer is usually photographed after the ink pass die is completed, and the positions of the defective chips on the picture are fitted to the front side of the wafer, and then cut according to the fitting result. However, due to the optical and image Due to various reasons such as depth scaling, errors are prone to occur in this process, and all defective chips cannot be correctly identified.

Specifically, optical reasons include unexpected offset during the photographing process, shadows caused by foreign objects, optical reflections, etc., or the color of the wafer is similar to the background and it is difficult to identify the wafer from the background, or it is difficult to identify the wafer The direction of the kerf, etc.; and the problem in the process of image depth scaling is usually due to the problem of the shooting angle that the captured wafer image is usually ellipsoidal, and it is difficult to reconstruct the defects on the wafer based on the ellipsoidal wafer image.

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