Patent for License:

Cluster tool    

A cluster tool for testing substrates and locating defects on the substrates utilizing a plurality of tools coupled via an automation platform.

Overview

The cluster tool includes an interface receiving storage device(s) having, each, more than one substrate contained therein. An inspection tool capable of inspecting the substrates and delivering defect map indicative of suspected locations on each of the substrates. The automation platform is coupled to the interface to the inspection tool, and to a review tool, and is capable of transferring substrates between the tools.

SUMMARY OF THE TECHNOLOGY
For simplicity, the description below predominantly focuses on a cluster tool that includes an inspection tool and a review tool. Those versed in the art will readily appreciate that the technology is by no means bound to this specific configuration. Thus, by way of non-limiting example, the technology is likewise applicable to a cluster tool that embodies two or more inspection tools or inspection tool and metrology tools.
The present technology aims at benefiting from the advantages of both the "integrated" tool approach and the stand alone mode. Thus, on the one hand, in accordance with the integrated approach, the interface between the inspection and review stages is simplified so as to reduce the overall duration of the inspection review cycle, and on the other hand, benefiting from the pipeline operation of the stand alone mode and conferring a high level of architectural flexibility. Flexibility, in this context, enables the treatment of each component separately, e.g. replacing either or both of the inspection and review components, in order to improve compatibility or essentially match the respective throughputs of the inspection and review tools by adding one or more review tools or inspection tools, all as required and appropriate.
Accordingly, the overall duration of the inspection-review cycle will be reduced whilst offering a high level of compatibility between the inspection and review stages, as stipulated by the specific application.
Generally speaking, according to the technology, an inspection metrology tool such as the specified WF-7xx series, is utilized for delivering a defect map. An automation platform is coupled to the inspection tool as well as to selected review tools. The automation platform is capable if automatically loading wafers from a cassette or pod into the inspection tool and, upon completion of the inspection phase, unloading it from the inspection tool and conveying it to the review tool for the review phase. The automatic procedure, in the manner specified, drastically reduces the "time to results" and saves an undesired overhead that is associated with the lengthy and error prone equivalent manual procedure as described above.
In contrast to the hitherto known cassette inspection-review cycle, the system of the technology provides for a "per wafer" or "single wafer inspection-review cycle" which drastically reduces time to results. More specifically, one is compelled to wait until all the wafers in the cassette (or, alternatively, an entire sample thereof) are inspected and loaded into the review tool in order to obtain the report of defects and malfunction. In contrast, according to the technology, after an individual wafer has been inspected, it is conveyed and loaded into the review tool (along with the relevant defect maps--which may, if desired, be unified into a single map representation), and a succeeding wafer from the same cassette is simultaneously loaded to the inspection tool. Thus, the report of possible defects and malfunctions in an individual wafer is already available once its review stage has been completed, and the need to wait for the report until the remaining wafers undergo inspection, is obviated.
The single wafer inspection-review cycle and the flexibility of the architectural design to suit the specific requirements of the application reduces the time required to obtain information as to defects and malftinctions in an individual wafer. Advancing the time that this information is available in the manner specified, correspondingly advances the application of preemptive actions (such as halting the production line re-configuring the manufacturing tools, changing reticles and so on), which eventually accomplish improved yield. Considering the requirements of a very high yield that the present IC technology poses in order to render production line profitable, it is readily appreciated that from a cost perspective, utilizing the system of the technology constitutes a significant advantage, especially in the "ramp-up" stage
Accordingly, by one aspect, the technology provides for a cluster tool for testing substrates and locating defects on the substrates utilizing a plurality of tools coupled via an automation platform, comprising:
an interface receiving storage media, each having a plurality of substrates contained therein;
an inspection tool inspecting the substrates and delivering defect maps indicative of suspected locations on each of said substrates;
at least one of a second tool selected from the group of inspection tool metrology tool and a review tool;
the automation platform coupled to said interface, said inspection tool, and to the at least one of the second tool, and transferring substrates between the tools;
wherein each of said inspection tool and second tool includes a stage for supporting said substrate.
By another aspect the technology provides for a cluster tool for testing substrates and locating defects on the substrates utilizing a plurality of tools coupled via an automation platform, comprising:
an interface receiving storage media, each having a plurality of substrates contained therein;
an inspection tool inspecting the substrates and delivering defect maps indicative of suspected locations on each of said substrates;
at least two of a second tool selected from the group of inspection tool, metrology tool, and a review tool; and
the automation platform coupled to said interface, said inspection tool, and to the at least two of the second tool, and transferring substrates between the tools according to at least one escalation criterion.
The architectural flexibility of the technology facilities utilization of an "escalated" mode of operation. In a typical, yet not exclusive, example of the latter, a single inspection tool and two review tools are utilized. The first review tool e.g. an optical microscope, having a low review resolution, serves for a first coarse review and classification of the mapped defects that were delivered from the inspection tool. A succeeding, and more accurate review tool, e.g. a SEM, is configured for the review and classification of only those defects that were not classified by the optical review tool and which require a higher review resolution.

Patent Summary

U.S. Patent Classes & Classifications Covered in this Patent:

Class 382: Image Analysis

This is the generic class for apparatus and corresponding methods for the automated analysis of an image or recognition of a pattern. Included herein are systems that transform an image for the purpose of (a) enhancing its visual quality prior to recognition, (b) locating and registering the image relative to a sensor or stored prototype, or reducing the amount of image data by discarding irrelevant data, and (c) measuring significant characteristics of the image.

Subclass 149: Fault or defect detection
Subclass 152: Tool, workpiece, or mechanical component inspection