ITR: Feedback Control of Thin Film Microstructure Using Multiscale Distributed Models

研究：本研究计划的目标是开发一个全面的理论，计算和实验程序，用于使用多尺度分布式模型的薄膜化学气相沉积中膜微结构的非线性基于模型的反馈控制。将开发用于多尺度分布式模型的分布式控制理论，并用于产生新颖的分析反馈控制器和估计器设计，其在多尺度闭环系统中实施期望的稳定性、性能和鲁棒性规范，并实现具有期望特性（例如，降低粗糙度）。本论文的研究动机是：（1）薄膜微结构控制的需求日益增长，（B）薄膜微结构对操作条件的任意变化具有高度的敏感性，（3）缺乏系统的、全面的反馈控制框架，可以在线形成薄膜微结构。多尺度分布式模型降阶的计算效率和精确算法的发展.多尺度降阶估计器和非线性反馈控制器的设计，使材料的微结构以理想的方式成形.在线诊断技术与多尺度分布式模型的集成以及控制理论基础问题的研究.将控制算法应用于模拟薄膜生长问题.开发和实验应用的实时集成测量/控制系统的实验室规模的等离子体增强化学气相沉积过程中，加州大学洛杉矶分校控制薄膜的微观结构和空间variations.Impact：该研究将提供一个基本的理解的性质的模型减少，优化和控制问题的多尺度分布式系统，开发具体的控制算法，可以很容易地在实践中实施，说明应用的控制方法，并获得调整准则的控制器的实施。软件包的开发和与公司的合作将是将研究成果转移到工业部门的手段。将研究融入教育将有利于教育工作者在过程控制和半导体制造方面教授高级课程。 新的控制算法，预计将导致显着的进步，我们的能力，形状，在线，材料的微结构在化学气相沉积薄膜。 信息技术（IT）是拟议研究的主要推动者和受益者。一方面，信息技术的发展，如高置信度计算、传感、数据处理和软件系统的进步，为实现项目目标提供了不可或缺的机制。反过来，这项研究有可能通过改进半导体制造技术进一步推动IT发展，这些技术是现代IT基础设施的一个组成部分。

Research:The objective of this research program is to develop a comprehensive theoretical, computational and experimental program for nonlinear model-based feedback control of film microstructure in chemical vapor deposition of thin films using multi-scale distributed models. Distributed control theory for multi-scale distributed models will be developed and employed to produce novel analytical feedback controller and estimator designs that enforce the desired stability, performance and robustness specifications in the multi-scale closed-loop system and achieve thin film microstructure with desired characteristics (e.g., reduced roughness). The motivation for this work is provided by: a) the increasing need for control of thin film microstructure, b) the high-sensitivity of thin film microstructure with respect to arbitrary variations in operating conditions, and c) the lack of systematic and comprehensive framework for feedback control that can shape thin film microstructureon-line.To realize the desired objective, the proposed research will focus on the following projects:1. The development of computationally efficient and accurate algorithms for order reduction of multi-scale distributed models.2. The design of multi-scale reduced-order estimators and nonlinear feedback controllers that can shape material microstructure in a desirable way.3. The integration of on-line diagnostic techniques with multi-scale distributed models and the study of fundamental control theoretic issues.4. The application of the control algorithms to simulated thin film growth problems.5. The development and experimental application of a real-time integrated measurement/control system to a lab-scale plasma-enhanced CVD process at UCLA to control thin film microstructure and spatial variations.Impact:The research will provide a fundamental understanding of the nature of the model reduction, optimization and control problems for multi-scale distributed systems, develop concrete control algorithms that can be readily implemented in practice, illustrate the application of the control methods and derive tuning guidelines for the implementation of the controllers. The development of a software package and the collaboration with companies will be the means for transferring the results of the research to the industrial sector. The integration of the research into education would benefit educators teaching advanced-level classes in process control and semiconductor manufacturing. The new control algorithms are expected to lead to significant advances in our ability to shape, on-line, material microstructure in the chemical vapor deposition of thin films. Information Technology (IT) serves both as a major enabler and beneficiary of the proposed research. On the one hand, IT developments, such as advances in high-confidence computing, sensing, data processing, and software systems, provide an indispensable mechanism for realizing the project goals. In turn, the research has the potential to further advance IT developments through improved semiconductor manufacturing technologies that represent an integral part of modern-day IT infrastructure.