摘要:
A production management system has processing devices A, B, C, D, E, and P. A kind of product α is processed in the order of the processing devices A, P, B, P, and C, and a kind of product β is processed in the order of the processing devices D, P, E, and P. To determine whether the processing device P is to be used to produce the product α or the product β, an input ratio of each kind of product is multiplied by the number of times of passing the processing device P for each kind of product, thereby calculating a core of each kind of product. Based on the calculated score, whether the processing device P is to be used to produce the product α or the product β is determined. Accordingly, the work-in-process balance of key processes between different kinds of products can be equalized.
摘要:
A production management system has processing devices A, B, C, D, E, and P. A kind of product α is processed in the order of the processing devices A, P, B, P, and C, and a kind of product β is processed in the order of the processing devices D, P, E, and P. To determine whether the processing device P is to be used to produce the product α or the product β, an input ratio of each kind of product is multiplied by the number of times of passing the processing device P for each kind of product, thereby calculating a core of each kind of product. Based on the calculated score, whether the processing device P is to be used to produce the product α or the product β is determined. Accordingly, the work-in-process balance of key processes between different kinds of products can be equalized.
摘要:
A method for scheduling dual-armed cluster tools with wafer revisiting is provided. In order to speed up start-up transient processes, the present invention adopts a program evaluation and review technique for the analysis of start-up transient processes and develops optimization algorithms for their scheduling for dual-arm cluster tools. Then, their complexity is analyzed.
摘要:
In semiconductor manufacturing, there are wafer fabrication processes in cluster tools that need a wafer to visit some processing steps for more than once, leading to a revisiting process. Also, wafers may be subject to wafer residency time constraints. By considering atomic layer deposition (ALD) as a typical wafer revisiting process, this invention studies the challenging scheduling problem of single-arm cluster tools for the ALD process with wafer residency time constraints. By recognizing that the key to this problem is to schedule the robot tasks, the present invention presents different robot task sequencing strategies. With these strategies for different cases, the present invention performs the schedulability analysis and derives the schedulability conditions for such tools for the first time. If schedulable, the present invention proposes scheduling algorithms to obtain an optimal schedule efficiently. Illustrative examples are given to show the application of the proposed concepts and approach.