Data processing: generic control systems or specific application – Specific application – apparatus or process – Product assembly or manufacturing
Reexamination Certificate
1998-11-24
2001-07-17
Grant, William (Department: 2121)
Data processing: generic control systems or specific application
Specific application, apparatus or process
Product assembly or manufacturing
C700S100000
Reexamination Certificate
active
06263253
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a method for enhancing the allocation efficiencies of the bottleneck resources, and more particularly, to a method for dynamically allocating the bottleneck resources by increasing the total moves and reducing the lost time for all tools next to the bottleneck resources.
2. Description of the Prior Art
Nowadays, single manufacturing line never satisfies the desires of the modern factory, which implies that a modern factory should manufacture various products to achieve the purpose of decreasing risks and increasing profits. It is a common sense that each tool of the factory can be employed to manufacture at least one product. Therefore, it is important for the factory to control the stream flow when dispatching lots to the consecutive tools.
To establish an ideal dispatching model becomes a widespread discussed issue in the present days. However, it is difficult to construct such a model that achieves the requirements of the modern factory. One critical issue for achieving the aforementioned requirements is how to properly allocate the bottleneck resources. Therefore, there is still no theoretical dispatching model that provides information representative of whether the bottleneck resource has been properly allocated based on on-line current data. Conventional approaches for allocating the bottleneck resources is just to assume those tools next to the bottleneck resource have balance loading. In the semiconductor fabs, the manufacturing lines are rarely balanced especially in there ramp-up period. It is evident that the bottleneck resource may stock many lots waiting for processing, which indicates the capacities of the fabs can be significantly degraded.
Please refer to
FIG. 4
, which shows a block diagram representative of another bottleneck is arisen when an improper resource allocation is employed at the bottleneck resource in a semiconductor fab. For example, the bottleneck tools
401
of the semiconductor foundry fab are usually PEOX machines. Tools
1
~
4
indicate those tools next to the bottleneck tool
401
, such as the RTA, SACVD, and COATER machines etc. Sometimes, some of the tools
1
~
4
may be starving when they have no lots (e.g., Wafer-In-Process, WIP) for processing if the bottleneck tools
401
are not allocated properly. Another bottleneck next to the tools
1
~
4
will thus be arisen because there is no lots for performing the consecutive processes, too. A need has been arisen to disclose a method that suggests a theoretical model for allocating the bottleneck resources in accordance with the on-line data, in which the above-mentioned disadvantages such as the lost time of the tools can be minimized.
SUMMARY OF THE INVENTION
It is an object of the invention to provide an allocation method for a factory to optimally allocate the bottleneck resources.
The other object of the invention is the provision of the allocation method that improves the cycle time of the products and thus increases the factory capacities.
It is a further object of the invention to provide the allocation method to improve the utilization of all machines.
Accordingly to the above purposes, the method disclosed in the present invention establishes a theoretical model for dynamically allocating the bottleneck resource according to the on-line current data. At first, the current data are downloaded from the bottleneck resource and the tools next to the bottleneck resource (next tools). The on-line current data basically encompasses a total number of the next tools; a total number of the bottleneck tools; a total number of the WIP ready for processed by the one of the next tools; the number of the WIP that are going to dispatch to the next tools and currently processed in the bottleneck tools; the batch sizes, the average processing time, and the average throughputs of the next tools. Decision parameters such as the remaining processing time and buffer WIP of the tools next to bottleneck resource are sequentially derived by using the current data. Each tool next to the bottleneck resource is then determined to receive additional lots from the bottleneck resource or not. Finally, the bottleneck resource is reallocated to those tools that requires the lots from the bottleneck resource.
REFERENCES:
patent: 5408663 (1995-04-01), Miller et al.
patent: 5841677 (1998-11-01), Yang et al.
patent: 5946212 (1999-08-01), Bermon et al.
patent: 6092000 (2000-07-01), Kuo et al.
Chen Wen-Yao
Huang Yu-Feng
Yang Tai-Yi
Grant William
Nath & Associates PLLC
Novick Harold L.
Rapp Chad
Taiwan Semiconductor Manufacturing Co. Ltd.
LandOfFree
Method for allocating bottleneck resources does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for allocating bottleneck resources, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for allocating bottleneck resources will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2466352