摘　　　　　要　　　　　　　


本論文擬對電漿加工中所涉及之電漿與工件表面之傳輸現象及薄金屬液層於冷工件上之快速固化熱傳現象進行探討，本文區分為兩個單元，於第一單元中廣泛探討薄融化金屬液層於冷工件上之快速固化熱傳現象和液層底部的熱傳係數，液層的快速固化是由非平衡的動力條件所支配，而工件之融化是由平衡的融化溫度所支配，本文採用傳統的相變化問題來模擬此物理現象，並解一維的非穩態熱傳導方程式，其中液層與工件及相與相間的各種不同熱、物理性質皆被考慮，結果顯示出各種獨立無因次參數，如Stefan number、接觸 Biot number、動力係數、液層的初始溫度、平衡融化溫度、成核溫度、固體的熱傳導係數、工件的平衡融化溫度、固體與液體的熱傳導係數、液層與工件的比熱比、潛熱比、工件與液層的密度比，對於液層與工件之非穩態溫度分佈及液層固化率、工件融化率和液層底部的熱傳係數之改變量的影響，另外結果也顯示出非穩態之液層底部的熱傳係數或Biot number之改變量，可分為五種情況：液體液層與固體工件、液體液層與液體工件、固體液層與固體工件、固體液層與液體工件及液體液層成核固化時，本文也結論出如何適當地選取各無因次參數，以掌控液層的固化及工件的融化之起始時間，並提供液層底部的熱傳係數之了解與預測。
　　第二單元擬探討電漿與工件表面之間的各項轉換變數之關係，本文所討論之無碰撞Presheath區，乃位於Sheath區與電漿之間，而Sheath區，乃位於可反射離子和電子之平面工件表面與Presheath區之間，其中正離子與電子的速度分佈函數及各項轉換變數，經由動力分析模式，獲得解析解。因為接近工件表面之離子與電子的速度分佈函數呈現高度非Maxwell-Boltzmann速度分佈函數，固擬精確預測其離子與電子之密度、流體速度、平均壓力、黏滯應力和熱流量等轉換變數，需要應用動力分析模式。研究結果顯示Presheath區和Sheath區中之離子與電子的各項無因次量轉換變數，可以由獨立無因次參數離子與電子的反射係數、Presheath邊界上電子與離子的溫度比、離子與電子的質量比和電荷數等所組成的超函數所表示。本文並探討各種獨立無因次參數對於工件表面上之各項轉換變數之影響。另本文也對所預測之Presheath區和Sheath區中之離子與電子的各項無因次量轉換變數之結果與Schwager和Birdsall(1990)所預測之結果做一比對。

　　　　　　　英　文　摘　要　　　　　　　


Heat transfer of a molten splat to a thin layer rapidly solidified on a cold substrate and the heat transfer coefficient at the bottom surface of a splat is extensively and self-consistently investigated. Rapid freezing in the splat is governed by a nonequilibrium kinetics at the solidification front in contrast to the melting in the substrate simulated by the traditional phase change problem. Solving one-dimensional unsteady heat conduction equations and accounting for distinct properties between phases and splat and substrate, the results show the effects of dimensionless parameters such as the dimensionless kinetic coefficient, stefan number, latent heat ratio, initial, equilibrium melting, and nucleation temperature, and conductivity, density, and specific heat ratios between solid and liquid and splat and substrate on unsteady temperature fields and freezing and melting rates in the splat and substrate and on unsteady variation of Biot number are presented. The unsteady variation of the heat coefficient or Biot number can be divided by five regimes: liquid splat-solid substrate, liquid splat-liquid substrate, solid splat-solid substrate, solid splat-liquid substrate, and the nucleation of the splat. Appropriate choices of dimensionless parameters to control the time for freezing and melting of the splat and substrate and an understanding and estimation of the heat coefficient at the bottom surface of the splat therefore are presented.
The velocity distribution function and transport variables of the positive ions and electrons in the collisionless presheath and sheath of a plasma near a wall partially reflecting ions and electrons are determined from a kinetic analysis. Since velocities of the ions and electrons near the wall are highly non-Maxwell-Boltzmann distributions, accurate predictions of transport variables such as density, fluid velocity, mean pressure, fluidlike viscous stress and conduction require kinetic analysis. The result find that dimensionless transport variables of ions and electrons in the presheath and sheath can be exactly expressed in terms of transcendental functions determined by dimensionless independent parameters of ions and electrons reflectivities of the wall, ion-to-electron mass ratio, charge number and electron-to-ion temperature ratio at the presheath edge. The effects of the parameters on transport variables at the wall are also obtained. The computed transport variables in the presheath and sheath show agreement with available theoretical data for a completely absorbing wall.

　　　　　　　目　　　　　錄　　　　　　　


目　　錄-------------------------------------------------------------------------- 1
圖表索引-------------------------------------------------------------------------- 4
摘　　要-------------------------------------------------------------------------- 9
英文摘要-------------------------------------------------------------------------- 11
符號說明-------------------------------------------------------------------------- 13
第一章　緒論-------------------------------------------------------------------- 18
　　　　1-1薄金屬液層於冷工件上之快速固化現象------------------ 18
　　　　　 1-1-1研究背景-------------------------------------------------- 18
　　　　　 1-1-2研究目的-------------------------------------------------- 19
　　　　　 1-1-3文獻回顧-------------------------------------------------- 19
　　　　　 1-1-4研究範圍-------------------------------------------------- 21
　　　　1-2無碰撞Presheath與Sheath區動力模式之
　　　　　 轉換變數探討--------------------------------------------------- 21
　　　　　 1-2-1研究背景-------------------------------------------------- 21
　　　　　 1-2-2研究目的-------------------------------------------------- 22
　　　　　 1-2-3文獻回顧-------------------------------------------------- 23
　　　　　 1-2-4研究範圍-------------------------------------------------- 25
第二章　理論分析-------------------------------------------------------------- 26
　　　　2-1薄金屬液層於冷工件上之快速固化現象------------------ 26
　　　　　 2-1-1前言-------------------------------------------------------- 26
　　　　　 2-1-2基本假設及考慮----------------------------------------- 26
　　　　　 2-1-3統御方程式的建----------------------------------------- 26
　　　　　　　　2-1-3-1液層的熱傳導方程式------------------------- 27
　　　　　　　　2-1-3-2工件的熱傳導方程式------------------------- 27
　　　　　　　　2-1-3-3無因次化的統御方程式---------------------- 28
　　　　　 2-1-4數值分析-------------------------------------------------- 30
　　　　　 2-1-5數值分析解的步驟-------------------------------------- 33
　　　　2-2無碰撞Presheath與Sheath區動力模式之
　　　　　 轉換變數探討--------------------------------------------------- 34
　　　　　 2-2-1前言-------------------------------------------------------- 34
　　　　　 2-2-2基本假設及考慮----------------------------------------- 35
　　　　　 2-2-3離子分佈函數的建立----------------------------------- 36
　　　　　　　　2-2-3-1Sheath區中離子分佈函數的建立----------- 37
　　　　　　　　2-2-3-2Presheath區中離子分佈函數的建立------- 39
　　　　　　　　2-2-3-3Presheath區和Sheath區之離子分佈
　　　　　　　　　　　函數的結合-------------------------------------- 42
　　　　　　　　2-2-3-4離子密度---------------------------------------- 43
　　　　　 2-2-4電子分佈函數的建立----------------------------------- 44
　　　　　　　　2-2-4-1 Sheath中電子分佈函數的建立------------- 44
　　　　　 2-2-5 Presheath區離子之探討------------------------------- 45
　　　　　　　　2-2-5-1 Bohm準則-------------------------------------- 47
　　　　　　　　2-2-5-2離子密度----------------------------------------- 48
　　　　　　　　2-2-5-3離子質量流量----------------------------------- 49
　　　　　　　　2-2-5-4離子動量流量----------------------------------- 50
　　　　　　　　2-2-5-5離子能量流量----------------------------------- 52
　　　　　　　　2-2-5-6在Presheath邊界上的平衡狀態------------ 53
　　　　　 2-2-6 Sheath區離子之探討----------------------------------- 53
　　　　　　　　2-2-6-1離子密度----------------------------------------- 56
　　　　　　　　2-2-6-2離子質量流量----------------------------------- 57
　　　　　　　　2-2-6-3離子動量流量---------------------------------- 57
　　　　　　　　2-2-6-4離子能量流量---------------------------------- 59
　　　　　 2-2-7 Sheath區電子之探討----------------------------------- 59
　　　　　　　　2-2-7-1電子密度---------------------------------------- 59
　　　　　　　　2-2-7-2電子質量流量----------------------------------- 60
　　　　　　　　2-2-7-3電子動量流量----------------------------------- 60
　　　　　　　　2-2-7-4電子能量流量----------------------------------- 61
　　　　　 2-2-8工件表面之條件----------------------------------------- 62
第三章　結果和討論---------------------------------------------------------- 64
第四章　結論------------------------------------------------------------------- 78
參考文獻------------------------------------------------------------------------ 141
附 錄 A------------------------------------------------------------------------- 148
自　　述------------------------------------------------------------------------ 150

　　　　　　　參　考　文　獻　　　　　　　


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