Research on AOCTPN-based modeling and simulation technology of semiconductor fabrication line

There was a lack of modeling technology for the line fabrication of semiconductors under multi-agent-based scheduling and control status in quo. To resolve this problem, an AOCTPN modeling technology for a semiconductor fabrication line was proposed. The interior behavior of the machine agent was encapsulated and the hierarchical multi-agent-based semiconductor fabrication line model was separated into the system layer, the machine group layer, and the machine agent layer, which reduced the complexity and improved the reuse of the model. In addition, a distributed discrete event simulation platform was built to evaluate the performance of the multi-agent-based semiconductor fabrication line. An illustrative example of a 6-inch semiconductor fabrication line in Shanghai demonstrates the effectiveness of this approach .     

Medium-term multi-plant capacity planning problems considering auxiliary tools for the semiconductor foundry

The foundry is an industry whose demand varies rapidly and whose manufacturing process is quite complicated. This paper explores issues on mid-term capacity planning in the foundry. First, issues on capacity planning of the foundry are categorized. Second, focusing on multi-site planning, an increment strategy for the number of auxiliary tools—“photo mask”—is proposed to increase the flexibility of production. The related decisions include how to allocate appropriately the forecast demands of products among multiple sites and how to decide on the production quantities of products in each site after receiving customer-confirmed orders. By constructing the mathematical programming model of capacity planning, the rates of capacity utilization and customer order fulfillment are found to be effectively enhanced by adding new masks to increase production flexibility. Furthermore, from the sensitivity analysis, the importance of customers is shown to influence significantly the amount of reserved capacity of customers. Increasing the number of certified factories is also an indirect way to increase capacity. For long life cycle products, the verification of products in multiple factories in order to increase capacity utilization rate effectively is suggested.     

半导体生产线动态在制品水平控制方法

针对半导体晶圆制造中设备众多,生产周期长和多次重入等特点,提出一种在制品水平分解控制方法.首先,通过仿真实验,依据系统关键指标受设备性能变化影响的灵敏度大小,确定设备的约束权重;然后,依据设备约束权重,结合产品的加工参数,确定每种产品各加工阶段合理的在制品水平分布;最后,设备依据实际在制品水平和目标在制品水平的差别和上下游信息,动态地选择工件加工.通过仿真实验,验证了算法的可行性和有效性.     

性能指标驱动的半导体生产线动态派工方法

为了求解不确定生产环境下的半导体生产线调度问题,提出一种基于极限学习机的性能指标驱动的动态派工方法。首先通过半导体生产线仿真系统仿真,得到所需样本,进而通过极限学习机建立半导体生产线性能指标预测模型;然后通过预测出的性能指标,结合生产线的实时状态信息,学习产生调度过程中的动态派工规则算法所需的最佳系数,驱动生产线派工决策,使其性能指标趋向预测值,最终达到提高生产线整体性能的目的。通过仿真平台验证了该方法能够有效提高生产线的性能指标。     

半导体生产线动态调度方法研究

为了满足半导体生产线多目标优化要求,提出了多目标优化动态调度规则。它由正常状态调度规则、瓶颈设备较低在制品水平的调度规则、非瓶颈设备较高在制品水平的调度规则、多批加工设备调度规则以及紧急工件调度规则五种类型的调度规则组成。使用具有半导体生产线本质特征的简化模型,将多目标优化动态调度规则与先入先出法、最早交货期法、临界值法进行了比较,结果表明,多目标优化动态调度规则能够改善半导体生产线的整体性能,更好地优化模型的生产率、加工周期与在制品水平,最终提高准时交货率。     

Data acquisition system of compound semiconductor fabrication

Though compound semiconductor manufacturing technologies are very much similar to those of the silicon series memory devices, the production process control technologies tend to rely on the experiences of operators and managers because the production technology suitable for the characteristics of compound semiconductor fabrication has not yet been sufficiently developed, compared with that of silicon semiconductors. In addition, the semiconductor industry is being converted into mass customization production and an open foundry service for cooperation between businesses. In this study, a process data acquisition system suitable for compound semiconductors which collects data by operator input and equipment information extraction by using GEM was developed. The developed system was implemented in a real production system and compared with the conventional job card method. Through the application of the developed system, a foundation for constructing a real-time based MES (Manufacturing Execution System) was developed, with such expected effects as process information monitoring, meeting delivery schedule, and reducing lead-time.     

基于Agent的芯片制造生产线动态调度方法研究

基于智能体技术,提出了芯片制造生产线动态调度新方法,实现了投料调度、工件调度与设备维护调度的集成。首先,给出了基于智能体的动态调度模型,该模型中包括管理智能体、投料智能体、工件智能体、设备智能体、运输智能体与人员智能体。投料智能体用于实现投料控制,工件调度通过工件智能体与设备智能体之间的协商实现,设备维护调度由设备智能体实现。通过智能体间的合作,能够实现投料控制、工件调度与设备维护调度的协同进行。然后给出了工件智能体与设备智能体问协商使用的协商协议（即带有时间约束的单步协商协议）,以及智能体决策中使用的调度算法（包括投料调度算法,工件调度算法与设备维护调度算法）。最后,通过实例,给出了方法的使用过程,并进行了模拟仿真。仿真结果表明,集成的调度方法能更好地优化模型的生产率、加工周期与设备利用率,最终提高准时交货率。     

一种改进的半导体生产线批处理机调度策略研究

研究了半导体生产线上有加工类型限制的并行批处理机组调度问题,其目标是最小化总加权拖期交货损失,从而最大程度地满足客户的按期交货要求.在研究了ATC-BATC和DBDH规则的基础上,提出了一种改进的ATC-BATC调度规则,通过反馈控制局部在制品数量来改善系统性能,并通过仿真证明该规则能更有效地减小总加权拖期交货损失.     

3D环境下飞机装配工艺规划与仿真一体化模型

为实现3D环境下飞机装配工艺规划与仿真过程的集成和统一,提出了一种飞机装配工艺一体化模型。该模型综合了装配工艺设计对产品对象以及工装、工具等资源对象在信息组织管理、零件几何运动描述等方面的要求,确定了装配＂产品—资源—工艺＂间的层进映射关系,将产品对象和资源对象间复杂的1∶N或N∶1关系分解为具体的1∶1关系,并基于文件对象结构原理建立了其数学表示模型。以某飞机中央翼部件装配为例,将该建模方法应用到自主开发的数字化飞机装配工艺规划与仿真系统中,验证了所提方法的有效性。     

再生产业宏观战略规划的系统动力学建模与分析

循环经济理念已经成为减缓我国废旧产品不断增长所带来的巨大环保压力的指导性方针.但足目前尚缺乏基于具体国情的、支持废旧产品再生利用处置宏观战略规划的系统分析方法.本文引入系统动力学方法,首先研究再生利用处置系统通用动力学模型的构建问题,然后以电池产品的再生利用处置为例,研究并构建了该行业专用的动力学模型,仿真分析了不同政策场景下的不同宏观战略,设计对于系统关键变量的影响,以支持更为科学合理的再生产业宏观战略的规划及相关政策的制定.     

Heuristic scheduling policies for a semiconductor wafer fabrication facility: minimizing variation of cycle times

This paper presents heuristic scheduling policies for semiconductor wafer fabrication facilities. The proposed heuristic scheduling policies include the advanced operation due date (OPNDD) for a sequence control policy and the adaptive constant work-in-process (CONWIP) for an input release control policy. The objective of the proposed scheduling policies is to reduce the variation of cycle times in the wafer fab. The advanced OPNDD sets the higher priority to the front opening unified pod (FOUP) with the smallest operation due date that is computed using a generalized stochastic Petri net model, and at the same time regulates the queue lengths of the FOUPs in each stoker by preventing excessive queue lengths in bottleneck workstations. The adaptive CONWIP controls dynamically the input release time of FOUPs using the adaptive WIP level according to the current status of the wafer fab. The simulation experiments show that the proposed scheduling method is efficient in reducing the variation of cycle times.     

An industrial solution to object pose estimation for automatic semiconductor fabrication

To make control entities of flexible manufacturing systems (FMS) provided with characteristics of autonomy, cooperation, robustness, modularization, reconfiguration, maintainability, etc., we present in this paper a design method of autonomous and cooperative FMS control systems based on the latest agent standards of the foundation intelligent physical agent (FIPA). On the basis of discussing the concepts of the FIPA agent, the Java agent development framework (JADE) agent platform and FIPA specifications, the design method of FMS control systems is presented. Then the control software architecture and basic structure of a generic FIPA agent are designed. Finally, to demonstrate and validate the proposed design method, the prototyping FIPA agents have been implemented in MS 2000 Server/Professional Operating System, JADE and Java 6.0 Developer environments.     

Daily planning and scheduling system for the EDS process in a semiconductor manufacturing facility

Operations management in a complex manufacturing environment is practiced hierarchically: production planning and scheduling in sequence since the integrated approach is not efficient and practical. Production targets and allocation to the equipment are determined in the planning procedure by considering the only the critical factors, and the detailed scheduling is determined with more information needed to accomplish the production targets provided in the planning step. There is always, therefore, a gap between the planning and scheduling procedure, and some control parameters or factors are used to control those gaps. In this paper an approach connecting two procedures is suggested, which can be applied in the EDS (electrical die sorting) or the probe process in the semiconductor manufacturing. The EDS process requires very flexible operation management since the manufacturing processing time is relatively short and the supply of upstream fabrication and the demand of downstream assembly have to be met simultaneously. Daily planning and scheduling procedure are modeled to minimize the tester change-over within the daily target. Because of the relatively long setup change-over time, daily planning and scheduling have to be performed so that the time needed for the device and probe card change is minimized as possible. Mathematical programming is suggested for the problem, and the modified model is developed which can be solved in a practical computational time on a daily base. The scheduling heuristic with the planning data obtained from the suggested model, is designed, and their performance is evaluated through the computational experiment.     

P-EPS动力学模型的建立与仿真分析

建立P-EPS(单齿轮式电动助力转向系统)系统动力学模型,得到单齿轮式电动助力转向系统的传递函数。利用大型软件MATLAB编制相应程序,得到采用PID控制算法不同比例系数、积分时间常数和微分时间常数时的仿真对比曲线,并利用Simulink模块搭建系统模型对所建立的EPS动力学模型进行仿真分析     

恒定产冷量半导体制冷器的实验研究

分析了影响半导体制冷片产冷量与制冷效率的因素,设计出一种与制冷空间相分离的制冷器,并进行了恒定产冷量制冷实验,得到半导体制冷器在不同制冷功率、外界环境和制冷器安装位置等条件下的实验数据。利用Matlab数学软件对实验数据进行整理分析,得到不同条件下的温度曲线,并提出优化设计理念。该实验研究为半导体制冷系统的优化设计提供了实验依据。     

半导体封装测试生产规划辅助平台的研究

针对半导体封装测试生产线生产规划目前主要由手工操作、数据共享不及时以及工作效率低下等问题,分析了半导体封装测试生产线的任务规划流程及其特点,采用Microsoft.NET平台,并用SQL SEVER数据库与其进行无缝连接,以目前最先进的面向对象方法,并通过调研成一家半导体封装测试生产厂的实际生产情况,在该调研基础上开发的一个生产规划的辅助平台,用以指导实际生产,提高生产效率,最终,通过在该厂的应用效果表明,该平台确实有效解决了提出的问题。     

Ultrahigh vacuum-compatible fabrication and electrical characterization systems for environmentally sensitive metal oxide semiconductor capacitors

We describe an integrated, ultrahigh vacuum system for metal oxide semiconductor (MOS) device fabrication and characterization. This system is advantageous for electrical property measurements on electronic devices with environmentally sensitive materials and is especially important as device dimensions approach the nanoscale. Without exposure to atmosphere, MOS capacitors were fabricated by evaporatively depositing gate metal on molecular-beam-epitaxy (MBE) grown dielectrics through a shadow mask in an UHV electrode-patterning chamber. Finished devices were transferred in UHV to an in situ UHV electrical characterization probe station. We obtained excellent agreement between air-ambient ex situ and in situ probe station measurements with less than 0.3% systemic error for frequencies from 20 Hz to 1 MHz. We have successfully measured MOS capacitors with sensitivity to a density of interface states of 1x10(10) states cm(-2) eV(-1). These measurements show 0.5% systematic error for measurement frequencies from 20 Hz to 1 kHz and less than 0.1% from 1 kHz to 1 MHz. The integrated system presented here is one where complex, MBE-grown MOS heterostructures can be synthesized and tested rapidly to explore new field-effect-device physics and functionality.     

面向装配工艺规划与仿真的装配工具信息模型的研究

详细论述了装配工具信息模型建立的方法,研究了建立装配工具信息模型的相应策略,并以Pro/E为平台建立了相应的装配工具库系统并给出了搜索工具的算法流程.     

一体化半导体激光器的ANSYS热仿真及结构设计

传统半导体激光器与驱动控制器多采用分离式设计,故半导体激光器系统的体积很难紧凑化,而一体化半导体激光器存在电路集成度高,发热严重等问题,因此,本文提出了对半导体激光器进行一体化、小型化设计的方法。为了保证所设计的半导体激光器运行时系统温度分布均匀,输出激光不受温度变化影响,在结构设计之前,利用ANSYS软件对元器件集成度较高的电路板等热源进行了热仿真,提高了集成后结构的可靠性。仿真结果显示,优化设计后的半导体激光器一体化结构满足激光器温度要求,系统温度分布均匀,能保证激光器稳定运行。设计的新型半导体激光器的整体结构尺寸仅为85mm×95mm×115mm,不仅实现了半导体激光器与驱动控制器的一体化与小型化集成,并且结构中留有准直光路设计空间,便于后期的应用研究。