利用氮化鋁-氧化鋅與氧化鎂-氧化鋅共濺鍍薄膜製作雙異質接面結構之特性研究

AlN-ZnO and MgO-ZnO Cosputtered Films Prepared ZnO Double Heterojunction Structure

黃瑞皓(Ruei-Hao Huang)

指導教授 ： 劉代山

國立虎尾科技大學/電機資訊學院/光電與材料科技研究所/碩士(2012年)

摘要

本研究利用射頻磁控共濺鍍系統，分別利用氧化鋅、氮化鋁和氧化鎂靶材，製作未摻雜氧化鋅薄膜、氮化鋁-氧化鋅共濺鍍薄膜和氧化鎂-氧化鋅共濺鍍薄膜，再藉由不同環境熱處理活化薄膜中的摻雜原子，量測熱處理後薄膜之光電特性、光激發螢光發光特性、薄膜成分以及薄膜結晶構造，分析薄膜內部自由載子的形成機制與型態。研究結果顯示，氮化鋁-氧化鋅的部分，可藉由摻雜鋁原子含量來提升光學能隙且平均穿透率均可達80%以上，由XRD量測結果可以發現薄膜結晶性從未摻雜氧化鋅薄膜的c軸ZnO(002)優先成長方向的多晶逐漸變為非晶，氮化鋁-氧化鋅共濺鍍薄膜在不同環境熱處理下具有不同的活化機制，在氧氣環境熱處理之共濺鍍薄膜雖然可以有效補償薄膜中的氧空位缺陷，但其載子濃度不高，真空環境熱處理下之共濺鍍薄膜呈現高濃度之n型導電型態。在氧化鎂-氧化鋅的部分，一樣可以改變摻雜鎂原子的含量來調變光學能隙，隨著摻雜含量從5%到20%，光學能隙由3.34 eV到3.77 eV，在真空熱退火中，鎂原子摻雜理論值5%有較高的載子濃度，隨著鎂含量的增加載子濃度逐漸下降。接著利用氮化鋁-氧化鋅與氧化鎂-氧化鋅共濺鍍薄膜製作雙異質接面結構，利用共濺鍍氧化鋅薄膜當作緩衝層與阻擋層，可以減少未摻雜氧化鋅晶格失配，並讓電子電洞可以有效的在氧化鋅活化層複合，阻擋層為50 nm時，在室溫光激發螢光光譜可以發現其NBE的強度最強，本質缺陷變小，其載子濃度也呈現高濃度之n型導電型態。

關鍵字

射頻磁控共濺鍍 ； 氮化鋁 ； 氧化鎂 ； 氧化鋅 ； 伯斯坦-摩斯效應 ； 雙異質結構

並列摘要

AlN-ZnO and MgO-ZnO cosputtered films were prepared using a radio-frequency magnetron cosputtering system using AlN,MgO and ZnO targets. The samples were annealed to achieve dopant atom activation in different ambient environments. Measurement optical and electrical properties of the films after heat treatment,Optical characteristic ,PL characteristic and crystallize. The results, in AlN-ZnO , optical energy gap and the average penetration can be more than 80%,From the XRD measurement results can be found,thin film crystalline from undoped ZnO c-axis (002) Polycrystalline gradually becomes amorphous,the AlN-ZnO cosputtered thin film to have the different activation mechanism under the different environment annealed treatment.The oxygen environment annealed treatment cosputtered thin film although may compensate in the thin film effectively the oxygen vacancy flaw, However, the carrier concentration is not high, under the vacuum environment annealed treatment cosputtered thin film to present n of electric conduction state the highly concentrated.In MgO-ZnO, They can change the content of doped Mg atoms to modulate the optical energy gap, with the doping content from 5% to 20% , optical energy gap by 3.34 eV to 3.77 eV . In the vacuum thermal annealing, Mg doped theoretical value of 5% have a higher carrier concentration, With the increase in carrier concentration of the magnesium content decreased gradually. Then, the AlN-ZnO and MgO-ZnO cosputtered films prepare double heterostructure,use ZnO cosputtered films as buffer layer and barrier layer, Can reduce the undoped ZnO lattice mismatch,let electron-hole can be effective in the activation of ZnO layer composite,when barrier layer of 50 nm, Room temperature photoluminescence spectra can be found in the intensity of the NBE strongest, the nature of defects smaller, The carrier concentration also showed high concentrations of n-type conductivity type.
Keywords: RF magnetron sputtering, AlN, ZnO, MgO, Burstein - Moss effect, double heterostructure

並列關鍵字

RF magnetron sputtering ； AlN ； ZnO ； MgO ； Burstein - Moss effect ； double heterostructure

參考文獻

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