This work describes the development of a mathematical model of ahigh-pressure chemical vapor deposition (HPCVD) reactor and nonlinearfeedback methodologies for control of the growth of thin films in thisreactor. Precise control of the film thickness and composition is highlydesirable, making real-time control of the deposition process veryimportant. The source vapor species transport is modeled by the standardgas dynamics partial differential equations, with species decomposition reactions, reduced down to a small number of ordinary differential equationsthrough use of the proper orthogonal decomposition technique. This systemis coupled with a reduced order model of the reactions on the surfaceinvolved in the source vapor decomposition and film deposition on thesubstrate wafer. Also modeled is the real-time observation technique usedto obtain a partial measurement of the deposition process. The utilization of reduced order models greatly simplifies the mathematical formulation of the physical process so it can be solved quickly enough to beused for real-time model-based feedback control. This control problem isfairly complicated, however, because the surface reactions render the modelnonlinear. Several control methodologies for nonlinear systems are studiedin this work to determine which performs best on test examples similar tothe HPCVD problem. One chosen method is extended to a tracking control toforce certain film growth properties to follow desired trajectories. Thenonlinear control method is used also in the development of a stateestimator which uses the nonlinear partial observation of the nonlinearsystem to create an estimate of the actual state, which the feedback controlformula then can use to guide the HPCVD system. The nonlinear trackingcontrol and estimator techniques are implemented on the HPCVD model and theresults analyzed as to the effectiveness of the reduced order model andnonlinear control.

Chemical Vapor Deposition Polymerization - The Growth and Properties of Parylene Thin Films is intended to be valuable to both users and researchers of parylene thin films. It should be particularly useful for those setting up and characterizing their first research deposition system. It provides a good picture of the deposition process and equipment, as well as information on system-to-system variations that is important to consider when designing a deposition system or making modifications to an existing one. Also included are methods to characterizae a deposition system's pumping properties as well as monitor the deposition process via mass spectrometry. There are many references that will lead the reader to further information on the topic being discussed. This text should serve as a useful reference source and handbook for scientists and engineers interested in depositing high quality parylene thin films.

To design and analyze chemical vapor deposition (CVD) reactors, computer models are regularly utilized. The foremost aim of this thesis research is to understand how thin film uniformity can be controlled in a CVD reactor. A complete understanding of chemical reactions that take place both in gas phase and at the deposition surface is required to predict thin film properties such as growth rate and composition precisely, however, deposition rates and surface topography can be determined by the arrival flux of reactants in a mass-transfer limited regime. In order to understand experimental thickness and roughness uniformity, a predictive model has been developed to study the fluid dynamic effect on thin film growth in a horizontal type reactor using velocity, temperature, pressure and viscosity as tunable parameters upon which velocity profiles within a CVD reactor have been evaluated using computational fluid dynamic (CFD) calculations. Through this predictive model, it is shown that fluid velocity is the major variable contributing to transverse roll cell formation compared to temperature and pressure gradients present during thin film deposition in a meso-scale CVD reactor. These results provide a physical insight regarding improved reactor operation conditions that influence uniformity.

Semiconductor equipment modeling has in recent years become a field of great interest, because it offers the potential to support development and optimization of manufacturing equipment and hence reduce the cost and improve the quality of the reactors. This book is the result of two parallel lines of research dealing with the same subject - Modeling of Tungsten CVD processes -, which were per formed independently under very different boundary conditions. On the one side, Chris Kleijn, working in an academic research environment, was able to go deep enough into the subject to laya solid foundation and prove the validity of all the assumptions made in his work. On the other side, Christoph Werner, working in the context of an industrial research lab, was able to closely interact with manufacturing and development engineers in a modern submicron semiconductor processing line. Because of these different approaches, the informal collaboration during the course of the projects proved to be extremely helpful to both sides, even though - or perhaps because - different computer codes, different CVD reactors and also slightly different models were used. In spite of the inconsistencies which might arise from this double approach, we feel that the presentation of both sets of results in one book will be very useful for people working in similar projects.

AASERT supported work on the following: Modeling of multiple layer stacks in thin film growth; Modeling of energy input terms in electromagnetic excitation of materials; PRS monitoring of multiple layer stacks in thin film growth; construction and testing of a prototype high pressure organometallic chemical vapor deposition (HPOMCVD) reactor; Reduced order surface kinetic models for GaP growth; computational methods for feedback control in nonlinear systems.