Wafer copper film thickness on-line measurement module control system

Abstract

The invention discloses a wafer copper film thickness on-line measuring module control system. A two-stage control mode of an upper layer control system and a bottom layer control system is used, and the two layers of control system are in physical connection through an industrial Ethernet. A PLC and an on-line measuring module which is directly in charge of controlling a chemical mechanical polishing unit are used in the bottom layer control system, and a specially-used storage area for temporarily storing data collected by the measuring module in the technological process. An IPC is used in the upper layer control system, the bottom layer control system is used for monitoring the operation of the on-line measuring module, an OPC technology is used for actively reading the data in the bottom layer storage area, data processing is completed, and operating software is provided for technologists. Based on technological demands, a calibrating mode and a measuring mode are set in the wafer copper film thickness on-line measuring module control system, and a plurality of calibrating tables can be stored in a grouping mode to remove the influence of different technical formulas on measuring results. The wafer copper film thickness on-line measuring module control system has the advantages of being lossless in testing, simple in operation, convenient to maintain, good in expandability, safe and reliable.

Description

technical field [0001] The invention relates to the technical field of chemical mechanical polishing, in particular to an on-line measurement module control system for wafer copper film thickness. Background technique [0002] Chemical mechanical polishing (Chemical Mechanical Planarization, CMP) technology is one of the key technologies for preparing multi-layer copper interconnection structures in integrated circuit manufacturing. In the manufacturing process of integrated circuits, as the feature size continues to shrink, the requirement for global planarization has become higher and higher. As the most effective global planarization method at present, CMP technology can effectively take into account local and global flatness, and use the synergistic effect of chemical etching and mechanical grinding to achieve the best wafer polishing effect. [0003] The copper CMP process can be summarized into three steps: the first step removes a large amount of copper on the wafer ...

AI Technical Summary

Problems solved by technology

For the copper CMP process, the optical method generally judges when the end point is reached according to the change of the reflected light intensity, but the diffraction and scattering that occur due to the existence of the copper interconnection often affect the accuracy of the optical measurement, so it will affect the accuracy of the measurement

It is generally believed that the reliability of the end point detection technology based on friction is high, and the end point detection technology based on the change of the drive motor current has been really applied in industrial production practice, but it can only reflect the remaining copper on the wafer surface at the macro level, and cannot real-time Detect changes in copper film thickness

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