Method of preventing cmp overpolishing

By setting multiple detection windows and monitoring the changes in the endpoint detection curve during the CMP process, the problem of depression defects caused by over-grinding in CMP was solved, and accurate detection of the grinding endpoint and rate was achieved, thereby improving wafer yield.

CN122373707APending Publication Date: 2026-07-10SHANGHAI HUALI INTEGRATED CIRCUIT CORP
View PDF 0 Cites 0 Cited by

Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
SHANGHAI HUALI INTEGRATED CIRCUIT CORP
Filing Date
2026-03-18
Publication Date
2026-07-10

AI Technical Summary

Technical Problem

Existing CMP endpoint detection technology is prone to over-grinding during the grinding process, resulting in concave defects that cannot be effectively resolved. Existing technology cannot accurately determine the grinding endpoint, leading to wafer fragmentation.

Method used

Multiple detection windows are set during the CMP process, including the first, second and third detection windows. The change of the endpoint detection curve is monitored by the torque endpoint detection method. The relationship between the grinding rate and the endpoint detection curve is used to prevent over-grinding.

Benefits of technology

It enables dual detection of the grinding endpoint and grinding rate, preventing over-grinding, reducing wafer depression defects, and improving wafer yield.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure CN122373707A_ABST
    Figure CN122373707A_ABST
Patent Text Reader

Abstract

This invention discloses a method for preventing over-polishing in CMP, comprising: providing an underlying structure having a first pattern formed from a first material layer, wherein at least two hard mask layers are formed on top of the first pattern; forming a second material layer; performing CMP to expose the top surface of the first pattern, wherein endpoint detection is performed using a torque endpoint detection method, comprising: setting detection windows, including: a first detection window for detecting a first switching point between hard mask layers; a second detection window for detecting a second switching point when the top surface of the first pattern is opened; and a third detection window for detecting a third switching point when the hard mask layers are completely removed. As CMP proceeds, the first to third detection windows are sequentially checked to find the endpoint, including: if the first switching point is not found, CMP is stopped directly to prevent over-polishing; if the first switching point is found, CMP is stopped after sequentially finding the second and third switching points.
Need to check novelty before this filing date? Find Prior Art