快速熱處理器系統模擬及溫控器設計

Abstract

快速熱處理器是一個快速的溫度控制程序。隨著半導體製程的改良， 大面積、高密度及單晶圓愈來愈普遍，快速熱處理器的溫度控制也愈顯重 要。 本論文主要是針對電物系楊賜麟老師所提供的RTP機台做 研究。在論文中，我們針對矽晶圓，建立熱模型，模擬出它的熱傳物理現 象。除了做到物理現象的熱模擬，我們並用系統判別(system identification)方式求得晶圓中心溫度可控的數學模型。並根據此模型 來設計控制器。我們應用線性平方調節器(linear quadratic regulator) 和降階狀態估測器(reduced-order state estimator)來控制鹵素燈功率 。除此之外，我們也嘗試利用PID控制器來控制此鹵素燈功率，並利用最 佳化(optimal)理論來調整PID控制器參數，達到溫度控制的目的。 由 模擬實驗得知，我們運用線性平方調節器當控制器，晶圓中心溫度穩態誤 差在0.1度內。而運用PID當控制器，晶圓中心溫度穩態誤差也都在0.5度 內。這和熱電耦的解析度0.5度相比，可以證明我們的控制器已經滿足我 們所需。 It has been known that Rapid Thermal Processing(RTS)is a kind of rapid temperature-control process.In the recent years,the manufacture technology ofsemiconductor products has been improved greatly.The manufacturers tend to use big wafers to design the high density circuit,and RTP is the important process to this kind of products. In this thesis,we use a specified RTP furnace as our study target.We proposea complete procedure to simulate the whole system and to design a temperaturecontroller for it.We build up the thermal model for the furnace,simulate the associated heat transfer mechanism,and use system identification method to identify the approximate transfer function of the center temperature of waferversus the radiation power of ten of halogen tubes.With the usage of the identified model,we design two kinds of the temperature controllers.In the first one,a linear quadratic regulator and a reduced-order state estimator areemployed in controlling the power of halogen tubes.The other one is a PID con-troller,which is designed in base of optimal self-tuned theory. Our simulation results have shown very good temperature control performance.The system using the linear-quadratic regulator can be controlled accurately with a error only in 0.1 .For the PID controlled system,the temperature erroris 0.5 .Both two control errors are smaller than the resolution of the tradi-tion k-type thermal-couple meter.Thus,our controller has shown good enough performance to us.