臺灣博碩士論文加值系統

由於近年來光纖通訊頻寬需求逐漸增加，因此如何研製出具有超寬頻特性的增益介質成為了重要課題，目前掺鉻玻璃材料組成為CaO-GeO2-Li2O-B2O3(Al2O3)，因為具有良好的光學特性而備受矚目，其輻射波段1.2-1.5μm 涵蓋整個通訊波段，具有發展成超寬頻光源、光纖放大器、可調式波長雷射等潛力，本實驗室已成功自行研製出具有紅外光輻射特性的掺鉻玻璃(Cr-doped glasses)，為了改進其光學特性(螢光強度增加以及傳輸損耗減少)，分析在不同組成、摻雜不同成核劑以及不同熱處理下，其傳輸特性和內部結構的變化，我們將掺鉻玻璃樣品製作成具有高解析力的穿透式電子顯微鏡試片，掃描螢光強度以及拉曼位移(Raman shift)的二維圖形，解析出掺鉻玻璃經過熱處理後產生的奈米結晶顆粒(nanocrystal)螢光頻譜特性，以及探討不同製程下掺鉻玻璃內部的結晶分佈狀況，期望能達到均勻且儘可能小的奈米結晶顆粒，減少元件在傳輸上的損耗。在奈米光學研究方面，近場掃描式光學顯微鏡(near-field scanning optical microscopy)和高解析式穿透式電子顯微鏡(high-resolution electron microscopy)等技術在奈米光譜學與奈米結構研究上扮演了很重要的角色，本論文將掺鉻玻璃樣本製作成厚度在100μm 的高解析式穿透電子顯微鏡之試片，分析鉻離子三價與四價在不同相位下的頻譜變化，驗證鉻離子三價與四價離子是否存在於同一結晶之中，並利用調整極化片Polarizer 來得到100nm 的解析力，另外還探討掺鉻玻璃不同組成下結晶分佈狀況和顆粒大小，對螢光分佈進行圖像分析得知結晶的分佈面積，並測量鉻離子在玻璃中結晶Ramen shift 變化來得知結晶結構變化，進一步分析Cr 離子所存在的晶體相位為何，是否同時存在鉻三價離子與四價離子。

In recent years, the demand of the optical fiber communication bandwidth is increasing. Therefore, how to develop gain materials has become an important issue. The composition of a chromium-doped glass CaO-GeO2-Li2O-B2O3-Al2O3 is known to have good optical properties, the Cr-doped glass’s radiation wavelength 1.2-1.5μm covering entire communication band. The characteristics of a chromium-doped glass have potential to develop width band light source, optical amplifier and tunable wavelength laser. Our laboratory has successfully developed chromium-doped glass with infrared radiation characteristics. In order to improve it’s optical properties. For example, increasing fluorescence intensity and less transmission loss. We shape the chromium-doped glass samples produced to high resolution transmission electron microscope sample, scanning its fluorescence intensity and Raman shift, two-dimensional graphics, comparing the difference between quench and heat treatment glass sample. The nanocrystal with infrared radiation characteristics appear when the heat treatment Raise up to appropriate temperature. To prove the nanocrystal distribution more uniform, higher fluorescence intensity, and smaller size of the nanocrystal to decreasing the transmission loss . We use different composition, or different nucleating agents and different heat treatment ways to analyze its transmission characteristics and internal structural changes. Near-field scanning optical microscope (SNOM) and high-resolution electron microscopy play a very important role in nano research. We also adjust the polarization film Polarizer use to reach the high resolution about 100nm. With this thesis we can analysis whether Cr3+ ion and Cr4+ ion exist in the same phase of nanocrystal and mapping high resolution fluorescence distribution picture to know how the nanocrystal appear by heat treatment, distinguish different nanocrystal by Ramen shift.

目錄
致謝
中文摘要
英文摘要
目錄.......................................................................................... I
圖目錄........................................................................................II
表目錄........................................................................................V
第一章 緒論..................................................................................1
第二章 掺鉻玻璃之特性.............................................................3
2.1 掺鉻玻璃之結構特性.......................................................................3
2.2 掺鉻玻璃Cr3+能階、吸收及放射光譜特性.................................................4
2.3 掺鉻玻璃Cr4+吸收能階轉換及光譜特性.....................................................7
2.4 掺鉻玻璃Cr4+離子處於不同結晶的放射光譜.............................................9
第三章 儀器光學原理介紹....................................................................12
3.1 近場掃描式光學顯微鏡原理.......................................................................13
3.2 NSOM 之高度維持機制..............................................................................15
3.3 NT-MDT 儀器操作流程簡介......................................................................20
3.4 拉曼位移(Raman shift)測量原理.................................................................33
第四章 掺鉻玻璃的製備以及近場光學樣品的研製............................36
4.1 掺鉻玻璃的製成方法....................................................................................36
4.2 掺鉻玻璃樣品製備........................................................................................38
第五章 掺鉻玻璃之近場光學測量以及結構分析................................41
5.1 探討熱處理前後的結晶變化.......................................................................41
5.2 掺鉻玻璃Raman shift 結構分析..................................................................53
第六章 結論.............................................................................................56
參考文獻...................................................................................................57
圖目錄
圖 2 - 1 掺鉻離子在固體的激態4A2，激發態2E、4T2 的能階圖[2] ....4
圖 2 - 2Cr 離子所在的d3 軌域晶體強度(單位Racah 參數B)能階圖[4]
...................................................................................5
圖 2 - 3 (a)fluoride (G8197): (b)phosphate(G8222); (c) tellurite
(G8298) 不同種類的掺鉻玻璃的吸收頻譜.....................................7
圖 2 - 4 掺鉻玻璃的吸收頻譜(實線)，掺Cr3+鎂橄欖石吸收頻譜......8
圖 2 - 5 為Cr 三價離子與Cr 四價離子能階轉換示意圖[7] ................8
圖 2 - 6 [8]掺鉻玻璃螢光頻譜(a),(b),(c)為熱處理490℃時間逐漸拉長
的螢光頻譜，虛線為Cr4+:Li2CaGeO4，點線為Cr4+:Ca2GeO4......9
圖 2 - 7 [9] Cr4+離子存在於三種不同主要相位放射頻譜...................10
圖 2 - 8 host glass, glass-ceramics 以及Cr4+:Ca2GeO4 不同相位的
Raman shift 頻譜圖形比較.............................................................11
圖 3 - 1 NSOM head 示意圖..................................................................16
圖 3 - 2 NSOM 回授流程示意圖............................................................17
圖 3 - 3 下針時探針擺動示意圖...........................................................17
圖 3 - 4 系統回授流程...........................................................................19
III
圖 3 - 5 SNOM 探針示意圖....................................................................19
圖 3 - 6 Confocal 原理示意圖 [10]........................................................20
圖 3 - 7 Confocal 架構示意圖,以及標準片掃描結果...........................21
圖 3 - 8 掺鉻玻璃樣品用U4V00 所測量的吸收光譜.........................22
圖 3 - 9 SNOM 實驗架構示意圖............................................................23
圖 3 - 10 SNOM 操作PMT 流程圖.......................................................25
圖 3 - 11 SNOM 操作CCD 流程圖........................................................25
圖 3 - 12 SNOM 前置作業步驟..............................................................26
圖 3 - 13 SNOM 測量作業步驟..............................................................30
圖 3 - 14 校準針尖示意圖.....................................................................32
圖 3 - 15 分子吸收光子後可能產生的結果, 請注意拉曼散射..........33
圖 3 - 16 拉曼光譜法實驗裝置簡圖：MC, 分光儀; PMT, 光電倍增管;
DC, 直流電流放大器; D/A, 數位類比轉換器; PC, 光子計數器;
RED, 記錄器, 此處以電腦記錄並處理所得之拉曼光譜. ...........35
圖 4 - 1 改變組成後的陶瓷玻璃圖片外觀...........................................37
圖 4 - 2 AFM 測量掺鉻玻璃光纖...........................................................40
圖 5 - 1 使用100 倍物鏡擷取掺鉻玻璃不同熱處理結晶狀況...........42
圖 5 - 2 使用100 倍物鏡觀察結晶分佈狀況，由掺鉻玻璃樣品背面打
光(左圖)， 由掺鉻玻璃樣品正面打光..........................................42
IV
圖 5 - 3 不同熱處理溫度(無熱處理quench、425℃、525℃)的Cr3+離
子螢光頻譜..................................................43
圖 5 - 4 不同熱處理溫度(無熱處理quench、425℃、525℃)的Cr4+離
子螢光頻譜.......................................................................................44
圖 5 - 5 熱處理前的掺鉻玻璃樣品結晶分佈.......................................45
圖 5 - 6 右圖為經過熱處理溫度525 ℃後的結晶分佈.......................45
圖 5 - 7 532nm 波長反射與Cr4+離子的螢光分佈................................46
圖 5 - 8 圖像分析意示圖.......................................................................47
圖 5 - 9 比較掺鉻玻璃摻雜不同成核劑的輻射頻譜...........................51
圖 5 - 10 用633nm 波長的氦氖雷射激發的螢光頻譜........................52
圖 5 - 11 比較顆粒內外的R-line 變化狀況.........................................53
圖 5 - 12 掺鉻玻璃在熱處理以前Cr 離子存在的玻璃相位...............54
圖 5 - 13 掺鉻玻璃在熱處理以後Cr 離子存在的結晶相位...............54
圖 5 - 14 結晶與螢光缺陷Raman shift 比照........................................55

[1] Fei Peng*, Kai-ming Liang, An-min Hu “Nano-crystal glass–ceramics obtained from high alumina coal fly ash” Received 12 September 2006; received in revised form 23 February 2007; accepted 28 February 2007

[2]Y. Kalisky, “Cr4+-doped crystals: their use as lasers and passive Q-switches,” Progress in Quantum Electronics 28, 249 (2004).

[3]S. Sugano and Y. Tanabe, and H. Kamimura, “Multiplets of transition-metal ions in crystals,” Academic, New York (1970).

[4] R. C. Powell, “Physics of solid-state laser materials,” Springer, New York (1997).

[5] J. Phys.:“Disorder and the optical spectroscopy of Cr3+-doped glasses. II. Glasses with high and low
ligand fields” 1991

[6] M. Yu. Sharonov, A. B. Bykov, S. Owen, V. Petricevic, and R. R. Alfano “Spectroscopic study of transparent forsterite Nanocrystalline glass–ceramics doped with chromium”, Received October 2, 2003; revised manuscript received May 25, 2004; accepted May 27, 2004

[7] A Sennaroglu “Analysis and optimization of lifetime thermal loading in continuous-wave Cr 4+-doped solid-state lasers”, J. Opt. Soc. Am. B, 2001

[8] A.B. Bykov a,*, M.Yu. Sharonov a, V. Petricevic a, I. Popov b,
L.L. Isaacs b, J. Steiner c, R.R. Alfano a,”Synthesis and characterization of Cr4+-doped CaO-GeO2-Li2O-B2O3(Al2O3) transparent glass-ceramics”, Received 19 December 2005; received in revised form 8 September 2006

[9]M.Yu. Sharonov *, A.B. Bykov, T. Myint, V. Petricevic, R.R. Alfano
“Spectroscopic study of chromium-doped transparent calcium germanate glass-ceramics
‘Received 12 September 2006; received in revised form 23 February 2007; accepted 28 February 2007

[10] http://en.wikipedia.org/wiki/File:Confocalprinciple.svg, from Wikipedia, the free encyclopedia

[11] www.ch.ntu.edu.tw/faculty/Instrument/raman.htm, 金屬紫質共振拉曼光譜的研究