晶圆制造双闭环Interbay物料运输系统性能分析模型

A Performance Analysis Model for Semiconductor Wafer Fabrication Interbay Material Handling System with Double Closed-Loop

双闭环Interbay物料运输系统是300 mm晶圆制造系统至关重要的组成部分。为在设计阶段快速有效分析其运行性能,本文提出了一种扩展马尔可夫模型。该模型充分考虑了运输小车在外环、内环和捷径导轨关键节点的运行、堵塞、装卸晶圆卡等系统状态,抑制了多运输小车运行环境下的模型状态空间规模爆炸,提高了性能分析模型的准确性与运算效率。采用某晶圆制造企业实际生产数据,将扩展马尔可夫模型与仿真模型进行比较。结果表明:两者在空载运输小车到达时间间隔、系统搬运能力和运输小车利用率等关键指标方面相对误差值较小;扩展马尔可夫模型明显具有更高的分析效率。由此验证了提出的扩展马尔可夫模型用于双闭环Interbay系统性能分析是有效的。

Interbay material handling systems with double closed-loop have been critical subsystems of the 300 mm semiconductor wafer fabrication systems.To rapidly and effectively analyze the performances of the Interbay systems in their design stage,an extended Markov model was proposed.The vehicle's operation states in outer and inner closed-loops and shortcuts,such as moving.blocking,and loading/unloading wafer lots,were fully considered in the model.In addition,the state space explosion phenomenon of the model was suppressed.Thus,the accuracy and operational efficiency of the model were improved.With production data of a semiconductor wafer fabrication line,the proposed Markov model was validated and compared with a simulation model.The result shows that two models have a small relative error in the aspects of empty OHT's mean arrival time interval,system throughput capacity,and vehicle's mean utilization ratio.However,the proposed model is more efficient than the simulation model.It means that the proposed extended Markov model is effective.