本研究利用射頻磁控共濺鍍系統，成功地製作出本質特性之氧化鎂鋅(i-MgZnO)以及氧化鎂鈹鋅(i-MgBeZnO)薄膜；濺鍍靶材為氧化鋅(ZnO, 99.9 %)、氧化鎂(MgO, 99.9 %)、鈹(Be, 99.9 %)。討論與分析氧化鎂鋅以及氧化鎂鈹鋅薄膜晶向性、光特性與電特性，並將氧化鎂鋅及氧化鎂鈹鋅薄膜應用於深紫外光發光二極體元件之主動區。藉由調變不同濺鍍功率，得到薄膜中不同含量之鎂原子、鈹原子與鋅原子、不同能隙值之氧化鎂鋅與氧化鎂鈹鋅薄膜。在薄膜穿透光譜量測部分，所有薄膜穿透率皆在85 %以上；固定氧化鋅靶材功率為175 W，調變氧化鎂靶材功率由50 W提升至150 W，氧化鎂鋅薄膜的能隙值可從3.22 eV調變至3.97 eV；此外，固定氧化鎂與氧化鋅靶材功率分別為75 W及175 W，並調變鈹靶材功率由5 W提升至18 W，氧化鎂鈹鋅薄膜的能隙值可從3.42 eV調變至3.98 eV。將不同能隙大小之薄膜(氧化鎂鋅與氧化鎂鈹鋅)應用在紫外光發光二極體元件，比較三種不同結構之主動層。而三種結構分別為傳統的p-i-n結構及兩種不同阻障層之量子井結構。在發光二極體元件之發光強度比較，量子井結構發光二極體具有較佳之發光強度，因為量子井結構之主動層具有將載子侷限在主動層區域之能力，故能提升載子輻射復合發光之機率，提高發光二極體元件之發光效率。其中，p-i-n結構之主動層與量子井結構之井層，是以能隙值為3.44 eV之氧化鎂鋅所構成。兩種不同量子井之阻障層分別為氧化鎂鋅薄膜和氧化鎂鈹鋅薄膜，此兩者之薄膜能隙值為相似的，分別為3.97 eV與3.98 eV。而氧化鎂鈹鋅薄膜作為量子井阻障層之發光二極體元件，相較於以氧化鎂鋅作為量子井阻障層，擁有更佳之發光強度。歸因於氧化鎂鈹鋅阻障層具有較佳之薄膜品質。而在p-ZnO/i-MgZnO/i- MgBeZnO/n-MgZnO:Al量子井結構之深紫外光發光二極體，起始電壓及崩潰電壓分別為4.32 V及-11.3 V；而元件electroluminescence (EL)之發光波段，注入電流由5 mA提升至80 mA，所對應之發光波長由360.2 nm位移至368.1 nm；此一發光波長產生紅位移，歸因於主動區之熱效應的產生。

Intrinsic MgZnO (i-MgZnO) and MgBeZnO (i-MgBeZnO) thin films of various component ratios were deposited using a radio frequency (RF) magnetron co-sputter system. Thus deposited films exhibited different energy bandgaps and were stacked alternately to form the active layers of multi-quantum well deep ultraviolet light-emitting diodes (UVLEDs). To compare the properties of the films of different composition, three UVLEDs with different active layer structures and layer composition were fabricated. Two of them were constructed with quantum well structures that had the same well layers (emission layers) but different barrier layers, i-MgZnO and i-MgBeZnO, respectively. These barrier layers were properly deposited to achieve nearly the same energy bandgap. The other one was the traditional p-i-n structure with the emission layer made from the same material as that in well layer of quantum well structure. All the three UVLEDs showed similar electroluminescence (EL) spectra located from 360.2 nm, when operated at injection currents 10 mA. However, the EL intensity of quantum wells structure UVLEDs was higher than the traditional p-i-n structure, which was attributed to the quantum wells structure that confines carriers in the well layers, and improves the probability of radiative recombination. Moreover, it was found that the quantum wells structure UVLEDs with i-MgBeZnO barrier layers had higher emission intensity, compared to the one with i-MgZnO barrier layers. It was also demonstrated that the electric performance of the quantum well UVLED with i-MgBeZnO barrier layers was better than the one with i-MgZnO barrier layers. In particular, for the deep UVLEDs with a quantum wells structure p-ZnO/i-MgZnO/i-MgBeZnO/n-MgZnO:Al, where the bandgap of the well layer i-MgZnO thin films was 3.44 eV, and for the barrier layer i-MgBeZnO the energy bandgap was 3.98 eV, the turn-on voltage and the breakdown voltage were 4.32 V, and -11.3 V, respectively. The better performance for the UVLED with i-MgBeZnO barrier layers could be attributed to the better crystalline quality was measured by X-ray diffraction (XRD). It indicates that the quaternary i-MgBeZnO is a suitable material to be applied in deep UVLEDs.

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