氮化鋁-氧化鋅/氧化鋅/氮化鋁-氧化鋅雙異質接面及多重量子井結構之製作及特性研究

Investigating Characteristics of AlN-ZnO/ZnO/AlN-ZnO Structure Applied to Multi-Quantum Well

邱黌壬(Hung-Jen Chiu)

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(2015年)

https://doi.org/10.6827/NFU.2015.00180

摘要

本研究利用射頻磁控共濺鍍系統，分別利用ZnO、AlN靶材，製作未摻雜ZnO薄膜、AlN-ZnO共濺鍍薄膜，並以AlN-ZnO共濺鍍薄膜作為阻障層，未摻雜ZnO薄膜作為活化層製作雙異質結構以及量子井結構，再藉由真空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，在AlN-ZnO/ZnO/AlN-ZnO雙異質結構以及量子井結構在真空熱退火後，平均穿透率均可達80%以上，由於AlN-ZnO/ZnO介面處鋁原子擴散取代鋅原子，提供更多的電子載子，因此，與未摻雜ZnO相比，雙異質結構以及量子井結構之電子載子濃度有明顯提升。接著將AlN-ZnO阻障層及未摻雜ZnO井層重複堆疊形成多重量子井結構，可以發現，多層結構能提供更多的位能井，使更多的電子與電洞被侷限於位能井區中，增加電子與電洞的復合數量，進而致輻射複合放射峰強度隨著量子井的對數增加而有明顯的增強現象，當量子井的對數增加至二十五對時，由於過多的薄膜堆疊，導致結構中應力的大量累積，造成結晶特性變差，進而導致多重量子井薄膜之發光強下降，即使在對數大於25對時，發光強度會逐漸呈現一水平之趨勢。

關鍵字

射頻磁控共濺鍍 ； 氮化鋁 ； 氧化鋅 ； 雙異質結構 ； 量子井 ； 多重量子井

並列摘要

In this study, by using RF magnetron co-sputtering system with ZnO and AlN target, respectively, deposited un-doped ZnO thin films and ZnO doped Al thin film, and using AlN-ZnO sputtering thin film to be a barrier layer, un-doped ZnO thin films to be active layers to produce double heterostructures and multi-quantum well structure, second annealing under vacuum ambient activates the dopant atoms in the films. After annealing under vacuum ambient, We measured our samples about the electrical properties, optical properties of thin films with photoluminescence light-emitting properties and the composition with the film crystal structure and analysis the thin film carrier mechanism and conduction type. Result of the study, after annealing under vacuum ambient, observed the average transmittance were over 80% about the double heterostructure (AlN-ZnO/ZnO/AlN-ZnO) and multi quantum well structure, due to the interface of AlN-ZnO / ZnO diffusion of aluminum atoms substituted the zinc atom, to support more electronic carrier, therefore, comparing with the un-doped ZnO, the electron carrier concentration has improved significantly of the double heterostructure and Multi-Quantum Well structure. Next, the barrier layer(AlN-ZnO) and un-doped well layer(ZnO) repeat stacked to form a multi-quantum well structure, observed the multilayer structure can provide more potential energy well, so the more electrons and holes are confined to potential energy wells layer, leading to the peak intensity increases of the radiative recombination radiation with increasing the number of quantum wells and has significantly enhanced the phenomenon, when quantum well layer increased to thirty period, due to quantum well stacked a lots, the number of electron and hole composite reach a saturation, due to the structure with multilayer stack makes a lot of accumulated stress, caused by the crystallization characteristics worse, Which led to a multi-quantum well structure
luminous intensity rise less obvious, even the multiple-quantum well’s period were more than 25-period, the luminous intensity will gradually shows the trend of a level of saturation trend.

並列關鍵字

magnetron co-sputtering ； aluminum nitride ； zinc oxide ； double heterojunction structure ； quantum well ； multiple quantum wells

參考文獻

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