Macau University of Science and Technology

Naiqi Wu

Mengchu Zhou

Yan Qiao

Zhiwu Li

Fajun Yang

Qinghua Zhu

Liping Bai

Mohamed Khalgui

Oussama Karoui

Anis Koubaa

Emna Guerfala

Eduardo Tovard

Chunrong Pan

Zhongyuan Jiang

A system and method of controlling a cluster tool apparatus, wherein the cluster tool includes one or more processing modules and a robot that is configured to move a semiconductor product to and from the one or more processing modules, the cluster tool configured for processing semiconductor products. The method of controlling the cluster tool apparatus to perform a processing cycle includes receiving a plurality of system parameters from a user interface, wherein the system parameters relate to one or more processing steps of the processing cycle, determining a schedule for performing the processing cycle utilizing the one or more processing modules, wherein the schedule being determined based on a semiconductor product residency parameter.

Cluster tool apparatus and a method of controlling a cluster tool apparatus

A system and method of controlling a multi cluster tool system configured to process a semiconductor product includes a plurality of cluster tools arranged adjacent each other, a buffer module positioned between a pair of cluster tools, each cluster tool including a plurality of processing modules and a robot, the method of controlling a multi cluster tool system including receiving a plurality of system parameters from a user interface, wherein the system parameters correspond to one or more processing steps in a system cycle, wherein the system cycle is a cycle of processing the semiconductor product, determining a system schedule for defining the system cycle for processing a semiconductor product, the system schedule providing robot waiting times for each robot of each cluster tool, controlling, via a controller, the operation of each robot of each cluster tool based on the determined schedule.

Multi cluster tool system and a method of controlling a multi tool cluster system

Given a sequential resource allocation system (RAS) topology structure, a state space, called an impulse state space, corresponding to the impulse response of a linear time-invariant system (LTS), is computed by small enough configuration of the considered RAS. Given an initial resource configuration of a RAS which corresponds to an input of an LTS, a complete state enumeration can be obtained by defining the convolution of this configuration with the pre-computed impulse state space. One example embodiment reduces central processing unit (CPU) time to process instructions that compute a target state space of a RAS includes constructing an initial RAS and an initial state space, and extending the initial state space iteratively under a target resource configuration.

Systems and methods for reducing CPU time to compute state space of resource allocation system

A system and method for a cluster tool apparatus for processing a semiconductor product including processing modules located adjacent each other and configured to process a semiconductor module, loadlocks configured to retain and dispense unprocessed semiconductor products and each positioned adjacent one of the processing modules, a robot configured to load, transfer and unload a semiconductor product to and from the processing modules, a hardware controller in communication with the robot and executing a method to close down the cluster tool apparatus to an idle state, the method including determining a status of the processing modules, determining if a close down process is required based on the status or based on a close down signal, and, if required, determining a schedule for a close down process based on a semiconductor product residency parameter, and controlling the operation of the robot based on the schedule to perform the close down process.

A method determines an optimized production schedule of a production line including a hybrid multi-cluster tool formed by a plurality of single-arm tools and dual-arm tools interconnected with each other. The method includes determining time for individual operations of a robotic arm and a processing module in the plurality of single-arm tools and dual-arm tools; determining robot waiting time of the single-arm tools and dual-arm tools based on the time for individual operations and different connection relationships of the plurality of single-arm tools and dual-arm tools; determining whether the optimized production schedule exists using the determined waiting time, wherein the optimized production schedule only exists if the hybrid multi-cluster tool is process-dominant where the robot activity time of the plurality of single-arm tools and dual-arm tools is substantially shorter than processing time at the processing module; and determining the optimized production schedule if the optimized production schedule exists.

System and method for determining an optimized schedule of a production line

A power transmission system includes a plurality of electrical substations and a plurality of transmission lines arranged to connect the plurality of electrical substations to form a power transmission network; and a controller system arranged to control a power transmission within the power transmission network. The controller system includes: a detection module arranged to detect an occurrence of a fault in at least one faulty electrical substation of the plurality of electrical substations; and a restoration module arranged to at least temporally maintain an output power of the at least one faulty electrical substation; and wherein at least one of the plurality of electrical substations is operable to facilitate maintaining of the output of the at least one faulty electrical substation upon the detection of the occurrence of the fault.

System for controlling a power transmission system

Since single and dual-arm tools behave differently, it is difficult to coordinate their activities in a hybrid multi-cluster tool that is composed of both single- and dual-arm tools. Aiming at finding an optimal one-wafer cyclic schedule for a treelike hybrid multi-cluster tool whose bottleneck tool is process-bound, the present work extends a resource-oriented Petri net to model such system. By the developed Petri net model, to find a one-wafer cyclic schedule is to determine robot waiting times. By doing so, it is shown that, for any treelike hybrid multi-cluster tool whose bottleneck tool is process-bound, there is always a one-wafer cyclic schedule. Then, computationally efficient algorithms are developed to obtain the minimal cycle time and the optimal one-wafer cyclic schedule. Examples are given to illustrate the developed method.

Petri net-based optimal one-wafer cyclic scheduling of treelike hybrid multi-cluster tools

The scheduling problem of a multi-cluster tool with a tree topology whose bottleneck tool is process-bound is investigated. A method for scheduling the multi-cluster tool to thereby generate an optimal one-wafer cyclic schedule for this multi-cluster tool is provided. A Petri net (PN) model is developed for the multi-cluster tool by explicitly modeling robot waiting times such that a schedule is determined by setting the robot waiting times. Based on the PN model, sufficient and necessary conditions under which a one-wafer cyclic schedule exists are derived and it is shown that an optimal one-wafer cyclic schedule can be always found. Then, efficient algorithms are given to find the optimal cycle time and its optimal schedule. Examples are used to demonstrate the scheduling method.

Optimal one-wafer scheduling of single-arm multi-cluster tools with tree-like topology

Recent trends of larger wafer and smaller lot sizes bring cluster tools with frequent lot switches. Practitioners must deal with more transient processes during such switches, including start-up and close-down processes. To obtain higher yield, it is necessary to shorten the duration of transient processes. Much prior effort was poured into the modeling and scheduling for the steady state of cluster tools. In the existing literature, no attention has been turned to optimize the close-down process for single-arm cluster tools with wafer residency constraints. This invention intends to do so by 1) developing a Petri net model to analyze their scheduling properties and 2) proposing Petri net-based methods to solve their close-down optimal scheduling problems under different workloads among their process steps. Industrial examples are used to illustrate the effectiveness and application of the proposed methods.

Optimally scheduling of close-down process for single-arm cluster tools with wafer residency time constraints

For sustainable development, a refinery is required to save energy as much as possible so as to reduce the emission of greenhouse gas. In crude oil operations, oil transportation from storage tanks to charging tanks via a pipeline consumes a large portion of energy. It is vitally important to minimize energy consumption for this process. Since the oil flow resistance is proportional to the square of oil flow rate, the relation between energy efficiency and flow rate is nonlinear, which makes the problem complicated. The present invention addresses this important issue by formulating a linear programming model for the considered problem such that it can be efficiently solved. A real-world industrial case study is used to demonstrate the applications and significance of the proposed method.

Linear programming-based approach to scheduling of crude oil operations in refinery for energy efficiency optimization

A method for operating a follower vehicle in a vehicle platoon includes determining, during operation, whether the follower vehicle is operating in a normal state or an abnormal state based on an operation condition of a component of the follower vehicle, or a communication between the follower vehicle and a preceding vehicle in the vehicle platoon. The method further includes selecting a first control mode if the follower vehicle is in the normal state and a second control mode if the follower vehicle is in the abnormal state so as to control movement of the follower vehicle using the selected control mode. In the first control mode, the follower vehicle uses communication data received from the preceding vehicle in the vehicle platoon to control its movement. In the second control mode, the follower vehicle uses data obtained by one or more of its sensors to control its movement.

System and method for operating a follower vehicle in a vehicle platoon

Due to the trend of using larger wafer diameter and smaller lot size, cluster tools need to switch from processing one lot of wafers to another frequently. It leads to more transient periods in wafer fabrication. Their efficient scheduling and control problems become more and more important. It becomes difficult to solve such problems, especially when wafer residency time constraints must be considered. This work develops a Petri net model to describe the behavior during the start-up transient processes of a single-arm cluster tool. Then, based on the model, for the case that the difference of workloads among the steps is not too large and can be properly balanced, a scheduling algorithm to find an optimal feasible schedule for the start-up process is given. For other cases schedulable at the steady state, a linear programming model is developed to find an optimal feasible schedule for the start-up process.

Scheduling start-up process for time-constrained single-arm cluster tools

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.

Optimization of start-up transient processes for dual-armed cluster tools with wafer revisiting

A method for scheduling single-arm multi-cluster tools is provided. The present invention studies the scheduling problem of a single-arm multi-cluster tool with a linear topology and process-bound bottleneck individual tool. Its objective is to find a one-wafer cyclic schedule such that the lower bound of cycle time is reached by optimally configuring spaces in buffering modules that link individual cluster tools. A Petri net model is developed to describe the dynamic behavior of the system by extending resource-oriented Petri nets such that a schedule can be parameterized by robots' waiting time. Based on this model, conditions are presented under which a one-wafer cyclic schedule with lower bound of cycle time can be found. With the derived conditions, an algorithm is presented to find such a schedule and optimally configure the buffer spaces.

Optimal buffer space configuration and scheduling for single-arm multi-cluster tools

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.

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Macau, Macao

Naiqi Wu