跳到主要內容

臺灣博碩士論文加值系統

(44.192.48.196) 您好!臺灣時間:2024/06/14 16:09
字體大小: 字級放大   字級縮小   預設字形  
回查詢結果 :::

詳目顯示

我願授權國圖
: 
twitterline
研究生:林宗平
研究生(外文):Lin, Zong-Ping
論文名稱:化學氣相沉積溫度對硫化鋅紅外線穿透材料性質之影響
論文名稱(外文):The Effect of Chemical Vapor Deposition Temperature on the
指導教授:何主亮, 張晴生
指導教授(外文):Ju-Liang He, Chen-Sen Chang
學位類別:碩士
校院名稱:逢甲大學
系所名稱:材料科學研究所
學門:工程學門
學類:材料工程學類
論文種類:學術論文
論文出版年:1997
畢業學年度:85
語文別:中文
論文頁數:102
中文關鍵詞:化學氣相沉積硫化鋅破裂韌性抗沖蝕紅外線穿透
外文關鍵詞:Chemical vapor depositionZinc sulphideFracture toughnessSolid particle erosionInfrared transmittance
相關次數:
  • 被引用被引用:0
  • 點閱點閱:432
  • 評分評分:
  • 下載下載:0
  • 收藏至我的研究室書目清單書目收藏:1
摘 要利用化學氣相沉積法製備高密度、大面積之紅外線穿透材料,是近
二十年發展出來的技術。諸多紅外線穿透材料中,ZnS主要應用於遠紅外
線8∼12μm的波長範圍,如光罩與視窗之材料。利用低壓化學氣相沉積法
製備ZnS紅外線穿透材料,具有一般傳統的熱壓、燒結法所沒有的優點:
可獲得高純化與緻密性的沉積物,亦可生長大面積、幾何形狀複雜的塊材
。利用化學氣相沉積製備材料時,可藉由製程參數的調整來控制材料的性
質,製程參數包括沉積溫度、反應氣體濃度、氣體流量與生長速率等,而
其中沉積溫度為一重要的決定性因素。為了使ZnS能夠滿足8-12μm光窗或
多光譜(可見光與紅外線波段)光窗上應用的需求,故有必要瞭解化學氣相
沉積系統中的沉積溫度對ZnS之生長、光學性質與機械性質之影響。本研
究利用水平式化學氣相沉積反應器來生長多晶ZnS紅外線穿透學材料。實
驗中於各製程參數固定下只改變沉積溫度,並針對ZnS生長之影響作探討
。將所得之ZnS沉積層分別做XRD晶體結構分析、EDS成分分析與密度測量
,並利用掃瞄式電子顯微鏡(SEM)與光學顯微鏡觀察ZnS的微觀組織。另外
也分別進行機械性質與光學性質測定。機械性質包括硬度、破裂韌性與抗
沖蝕性。光學性質則利用光譜儀測量ZnS於0.35∼16μm(可見光與紅外線
波段)的穿透率。綜合實驗結果,進而分析與探討沉積溫度對ZnS的微觀結
構、機械性質與光學性質之影響。實驗結果顯示,在不同沉積溫度下會產
生不同顏色的ZnS,且各具有不同的微觀結構、機械性質與光學性質。經
XRD證實,不同沉積溫度所得ZnS的結構皆為具等向性的立方結構,而在高
沉積溫度時,ZnS會於(111)結晶面上產生一優先方位生長。隨沉積溫度的
提高,ZnS的晶粒亦隨之增大。晶粒大小直接影響ZnS的硬度及破裂韌性,
故隨著沉積溫度的提高,將會降低硬度值及破裂韌性值,兩者皆符合
Hall-Petch關係式。沖蝕試驗結果顯示,高沉積溫度下所得的白色ZnS,
其表面沖蝕後所造成的損傷情形較低沉積溫度所得之棕色ZnS的表面損傷
情形嚴重,此證實了低沉積溫度所得較大破裂韌性值的ZnS,具較佳的抗
沖蝕性。由光譜分析得知在波長大於14μm以後的光譜,是受限於ZnS之材
料本質因素,故改變沉積溫度並不會影響14μm以後的穿透率與長波長終
止邊。低沉積溫度所得之ZnS的紅外線光譜中,皆發現於6.3μm處有吸收
峰,此乃Zn-H鍵結所致。由於Zn-H鍵結所造成的吸收會降低長波長(4∼16
μm)的穿透率,而當沉積溫度超過700 ℃後,即可消除6.3μm處的吸收峰
,故可提高長波長的穿透率。短波長的光譜受ZnS的晶粒大小與空孔之影
響,使得高沉積溫度所得之ZnS的短波長終止邊小於低沉積溫度者。因此
,高沉積溫度所得之ZnS具有較大的短波長穿透率。種種實驗結果證實:
沉積溫度提高會降低ZnS的機械性質,但可以提高其光學性質。最佳沉積
溫度範圍大約620∼650 ℃,此時ZnS不但具有良好8∼12μm透光性,且具
適當之機械性質,正滿足了應用上之基本需求。

ABSTRACTThe use of chemical vapor deposition (CVD) process as a
method of producing large scale and compact components for the
infrared transmitting materials has been developed in the last
two decades. Among those materials, Zinc Sulphide is applied in
domes and windows which requires the transmittance in the
wavelength of 8 to 12μm. The low pressure chemical vapor
deposition(LPCVD) process's offering advantages over
conventional hot-press methods are the high purity, high density
the ability of producing large cponents with complex shapes.
Properties of CVD materials can be controlled by adjusting
process parameters such as working temperature, pressure, degree
of supersaturation, flow rate, growth rate, etc. Among which the
deposition temperature may be very critical to the subsequent
properties including optical properties and mechanical
properties. In this study, polycrystalline ZnS infrared
transmitting material was prepared by using a horizontal LPCVD
reactor. All the process parameters are fixed and deposition
temperature is changed from 560 ℃ to 850 ℃ to reveal the
effect on microstructure and the subsequent optical and
mechanical properties. X-ray diffractometry(XRD), energy-
dispersive spectrometry(EDS), optical microscopy(OM) and
scanning Electron Microscopy(SEM) were used to reveal the
microstructure of the deposits. Hardness value and fracture
toughness were determined using Vicker's indentation technique.
Erosion rate was measured by solid particle erosion method. The
optical properties were measured by using the spectrophotometer
with wavelength from 0.35μm to 16μm. Experimental results show
that the color of deposited ZnS changes as the deposition
temperature changes. The color of the deposit is brown at low
temperature while it becomes white and clear with increasing
deposition temperature from 560℃ to 850℃. A type of zinc
blende structure(β- phase) was found of the deposits all over
deposition temperatures with (111) texture at high deposition
temperatures. The grain size of ZnS increases with increasing
deposition temperature. Both hardness and fracture toughness are
a function of grain size and follow Hall-Petch equation. Solid
particle erosion test show that the deposits obtained at high
deposition temperature have more serious damage feature on the
surface.The spectrum shows that the deposition temperature does
not affect the transmittance in the range over 14μm as well as
the long wavelength cut-off, it is caused by the extrinsic
absorption in the ZnS. The IR spectrum shows that the deposit
obtained at lower deposition temperature exhibit a significant
6.3μm absorption band which is caused by the Zn-H stretching in
the ZnS. The Zn-H stretching could decrease the transmittance in
the range of 4 to 16μm. As the deposition temperature is
increased over 700℃, the 6.3μm absorption band disappears and
the transmittance in the range of 4 to 16μm increases. The
spectrum in short wavelength region of 0.35 to 2.5μm is
affected by the grain size and pores of the ZnS. This results in
that the deposits obtained at high deposition temperature has
shorter cut-on wavelength and larger transmittance in the range
of 0.35 to 2.5 μm.

QRCODE
 
 
 
 
 
                                                                                                                                                                                                                                                                                                                                                                                                               
第一頁 上一頁 下一頁 最後一頁 top