Method of detecting abnormal defects of bonding layer of contact hole in polysilicon

Abstract

The invention provides a method of detecting abnormal defects of a bonding layer of a contact hole in polysilicon. The method of detecting abnormal defects of a bonding layer of a contact hole in polysilicon includes the steps: taping out a wafer to an active region substrate structural pattern, and performing trap ion implantation on the test structure; taping out the wafer to a polysilicon structural pattern, and performing source drain electrode ion implantation on the test structure; taping out the wafer to a contact hole structural pattern, and enabling the active region substrate to communicate with the polysilicon by sharing the contact hole; and after the tungsten contact hole flattening technology, using an electron beam to scan and detect the defects of the test region. The method of detecting abnormal defects of a bonding layer of a contact hole in polysilicon can make a contribution to improvement of yield rate and product research by establishing the defect detection structure and the corresponding technology process, debugging the corresponding scanning condition, and establishing the on-line monitoring data indexes for the above problems.

Description

technical field [0001] The invention relates to the field of semiconductor integrated circuit manufacturing, and in particular to a method for detecting abnormal defects of an adhesive layer of a contact hole on a polysilicon. Background technique [0002] With the development of integrated circuit technology, the size of semiconductor process devices continues to shrink, and the bonding layer process of contact holes is more and more important, and it has become one of the key process steps that restricts product yield. like figure 1 As shown in the figure, during the research and development process of 28nm products, the thick adhesive layer at the bottom of the contact holes on the polysilicon will lead to abnormally high resistance values ​​of the contact holes, resulting in serious yield loss, which has become one of the technical bottlenecks restricting the improvement of 28nm product yield. . [0003] Under normal conditions, this defect cannot be detected by optica...

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Problems solved by technology

like figure 1 As shown, in the process of 28nm product development, the thicker bonding layer at the bottom of the contact hole on the polysilicon will lead to an abnormally high resistance value of the contact hole, resulting in serious yield loss, which has become one of the technical bottlenecks restricting the improvement of 28nm product yield.

[0003] Under normal conditions, this defect cannot be detected by optical scanning because the defect is located at the bottom of the contact hole on the polysilicon; at the same time, because the polysilicon itself cannot be directly conducted with the substrate, that is, it cannot provide electrons for the conduction of the substrate under normal conditions. Therefore, the problem of whether there is a high resistance value at the bottom of the contact hole cannot be detected under the condition of electron beam scanning

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