圖4-22 ~ 4-27 為氧化鋅薄膜分別為 5、10、15 層的變激發強度度 PL 光譜圖及 激發強度度對 IX-X / IDX與X-X 散射發光在 EHP 出現之前的發光強度度比例例圖。從光 譜圖中可以觀察到：在激發強度度 712 W/cm2時一樣有DoX、eAo與 DAP 的複合 發光以及eAo與DAP 個放出一個聲子的複合發光。而當激發強度度繼續增加到 1.18 kW/cm2時，可以看到有激子-激子散射發光的出現以及肩型的自由激子發光。而 在激發強度度為13.5 kW/cm2時，一樣有EHP 的產生。我們利利用冪定律律去做擬合，
可以得到α 值。
隨著鍍膜層數數的增加，激子-激子散射與激發強度度會有：1. X-X 散射發光出 現的激發強度度門檻並沒有改變、2. α 值與在 EHP 出現之前 IX-X
/ I
DX的比例例都都是上 升的，而接下來來我們將對這三個樣品進行行大範圍缺陷發光的分析，進而觀察缺陷 是否會對激子-激子散射發光有影響。我們將實驗結果放置於 4-28 圖，橫軸為層數數多寡，縱軸由上到下分別為 α 值(a)、在 EHP 出現前 IX-X
/ I
DX 的比例例(b)、激發門檻強度度(c)、ID/ I
DX的比例例 (d)，可以觀察到隨著層數數的增加，α 值、在 EHP 出現前 IX-X
/ I
DX的比例例逐漸上升，但 是激發門檻強度度並沒有改變。圖 4-29 為薄膜層數數不不同的樣品進行行大範圍發光光 譜分析，隨著薄膜層數數的增加，樣品缺陷也相對減少，所以可以看到缺陷發光隨 著層數數增加而減弱(圖 4-28(d))。實驗結果將於結論論與第一系列列比較做討論論。36 圖4-22 層數數為 5 層之變激發 PL 光譜
圖4-23 層數數為 5 層 (上)激發強度度對激子-激子散 射強度度比例例圖 (下)激發強度度對(激子-激子散射強 度度/束縛激子發光強度度)之比例例圖
圖4-24 層數數為 10 層之變激發 PL 光譜
圖 4-25 層數數為 10 層 (上)激發強度度對激子-激子 散射強度度比例例圖 (下)激發強度度對(激子-激子散射 強度度/束縛激子發光強度度)之比例例圖
37 圖4-26 層數數為 15 層之變激發 PL 光譜
圖4-27 層數數為 15 層 (上)激發強度度對激子-激子 散射強度度比例例圖 (下)激發強度度對(激子-激子散射 強度度/束縛激子發光強度度)之比例例圖
圖4-28 橫軸為層數數多寡，縱軸(a)α 值
(b)在 EHP 出現之前
I
x-x/ I
DX的比例例(c) 激發門檻強度度(d)I
D/ I
DX的比例例圖4-29 不不同層數數的大範圍發光 PL 光譜
38
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