A method for detecting metal defects

Abstract

The invention provides a method for detecting the defects of a metal, and the method comprises the steps: 1), providing a to-be-detected metal line which is buried in a dielectric layer and isolated by the dielectric layer; 2), removing the dielectric layer at one end of the metal line, exposing the end, and contacting with the end through a probe; 3), injecting an electron beam to the other end of the metal line and enabling the electron beam to be transferred to the probe end, or injecting the electron beam to one end of the other metal line, enabling the electron beam to move along the metal line, and absorbing a current value from the probe end in a moving process of the electron beam. If the current value is detected to change, it indicates that the metal has defects. According to the invention, the method employs the electron beam as a current source, and detects and locates the position of the defects through the current change caused by the moving of the electron beam. According to the invention, the method does not need to completely expose the metal line, does not introduce a new metal defect, is simple in operation, and is suitable for industrial production.

Description

technical field [0001] The invention relates to the field of semiconductor failure analysis, in particular to a method for detecting metal defects. Background technique [0002] At present, in the process of manufacturing wafers in the semiconductor integrated circuit process, holes or impurity particle defects in metal connections in the wafer are the main failure modes, which have a great impact on the wafer yield. Holes can cause open circuits in metal lines, and impurity particles may cause short circuits between metal lines, such as figure 1 An open circuit condition is shown, figure 2 For the short circuit of two metal lines. As the inter-metal spacing becomes narrower and the feature size (CD) of metal lines becomes smaller and smaller, metal defects generated in advanced semiconductor processes (28nm / 32nm) have also become an important reason for low chip yields. [0003] When the size of the defects is in the nanometer scale, a scanning electron microscope (Scan...

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Problems solved by technology

[0005] In view of the shortcomings of the prior art described above, the purpose of the present invention is to provide a method for detecting metal defects, which is used to solve the problems in the prior art that it is easy to artificially introduce additional defects and take a long time when detecting defects.

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