Detection method for silicon wafer warpage degree

Abstract

The invention discloses a method for detecting wafer warp degree, which relates to a detection process in the field of semiconductor. The detecting method comprises the following steps: two detecting lines which are vertical and intersected with a wafer center are selected from the surface of a wafer; and a plurality of detecting points are selected from each detecting line; before the wafer carries out certain processing procedure, the detecting device is used to measure a reference distance; after the wafer carries out certain processing procedure, the detecting device is used to measure the measuring distance; the measuring distance subtracts the corresponding reference distance to obtain a difference value of each measuring point; if the difference value is within the permissible value range, the difference values obtained respectively by two detecting points on the two detecting lines on the same circumference of the wafer are compared; if two difference values are same, the warp of the wafer is proved not to influence the subsequent processing procedure; and if the two difference values are different, the warp of the wafer is proved to influence the subsequent processing procedure. The detecting method provided by the method can effectively and timely detect whether the wafer warp is even or not, and avoid abnormal aligned mark position in the subsequent processing procedure.

Description

technical field [0001] The invention relates to a detection process in the field of semiconductors, in particular to a method for detecting whether the degree of warpage of a wafer will affect subsequent manufacturing processes. Background technique [0002] During the lightly doped source-drain (LDD) photolithography process of the wafer, the position of the alignment mark in some regions of the wafer is often abnormal. This is because after the wafer undergoes certain processes such as thermal oxidation, the wafer warps and exceeds the allowable value range, but no timely compensation and correction is performed. In order to avoid the above situation, the usual practice in the industry is to check whether the degree of warpage of the wafer is within the allowable range after the wafer undergoes certain processes. [0003] In order to facilitate detection, a notch mark 4’ is set at a certain position of the wafer, please refer to figure 1 . The existing detection method ...

AI Technical Summary

Problems solved by technology

That is to say, the existing inspection method cannot detect whether the warpage of the wafer is uniform

Images