Chemical mechanical polishing apparatus and chemical mechanical polishing method thereof

Abstract

A chemical mechanical polishing apparatus and a chemical mechanical polishing method thereof are provided. The chemical mechanical polishing method at least includes the following steps. In step a, a positive pressure is formed between a polishing pad and a wafer. In step b, the wafer is driven to revolve around a first central axis. In step c, a polishing slurry is injected between the polishing pad and the wafer. In step d, the positive pressure formed on the wafer by the polishing pad is adjusted for change the contacting modes of the polishing pad and the wafer as well as the wafer removal rate.

Description

[0001]This application claims the benefit of Taiwan application Serial No. 96128302, filed Aug. 1, 2007, and Taiwan application Serial No. 97108401, filed Mar. 10, 2008, the subject matter of which is incorporated herein by reference.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The invention relates in general to a chemical mechanical polishing apparatus and a chemical mechanical polishing method thereof, and more particularly to a chemical mechanical polishing apparatus for polishing the wafer and a chemical mechanical polishing method thereof.[0004]2. Description of the Related Art[0005]For semiconductor elements, the wire density is increasing but the wire pitch is decreasing, the flatness on the surface of the wafer must be maintained at a certain level. When the difference between the protrusion and the indention on the surface of the wafer is too large, the focusing precision during the optical-lithography manufacturing process will be severely affected. Dur...

AI Technical Summary

Benefits of technology

[0013]The invention is directed to a chemical mechanical polishing apparatus and a chemical mechanical polishing method thereof. By way of adjusting the positive pressure, the chemical mechanical polishing apparatus and the chemical mechanical polishing method thereof at least have the advantages of avoiding dishing effect and erosion effect and preventing the low-K material and the copper material from being detached.

Problems solved by technology

When the difference between the protrusion and the indention on the surface of the wafer is too large, the focusing precision during the optical-lithography manufacturing process will be severely affected.

However, as the wire density keeps increasing but the wire pitch keeps decreasing, conventional chemical mechanical polishing apparatus 900 and polishing method thereof encounter many problems that are hard to be resolved.

Firstly, there comes dishing effect problem.

The RC-delay effect reduces signal transmission rate and increases cross talk noise and power consumption.

The copper wire 921a has a lower hardness level and is not easy to form a protective oxidation layer.

Secondly, there comes the erosion effect problem.

During the polishing manufacturing process, the insulating layer 921c are often over polished and resulted in erosion effect E.

Thirdly, the throughout is decreases.

During the polishing manufacturing process, the dishing effect D and the erosion effect E often occur concurrently, largely affecting the defect rate of the product.

Fourthly, manufacturing process is difficult to be integrated.

However, the low-K material has low stiffness, low fracture to ugliness, low hardness and instability.

Therefore, during the polishing manufacturing process, the low-K material is likely to be adhered onto hetero material and results in detachment.

Fifthly, the yield rate decreases and cost increases.

Conventional chemical mechanical polishing apparatus 900 and the polishing method thereof often result in defected products which cannot be repaired and are wasted, not only reducing the yield rate but also increasing manufacturing cost.

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