為了解決傳統氧化銦錫(ITO)電極導熱性差及能障較大的瓶頸，本研究採用寬能隙且的氮化鎵(n-GaN)取代ITO電極。透過能階匹配結構與高電子遷移率分析，n-GaN基板能顯著降低電子注入能障，並具備優異的電洞阻擋功能以有效侷限載子。從XRD、HR-TEM 與 SAED 微觀分析進一步證實，在CsPbBr3未退火狀態下，n-GaN 的極性表面能有效誘導CsPbBr3 (002) 晶面與 GaN (0002) 晶面幾何對齊，促使薄膜定向結晶生長並減少晶界缺陷。ITO 基板則呈現隨機生長。證實n-GaN具備平整且具極性的表面特性可誘導CsPbBr3沿特定晶面排列，改善隨機成核現象並有效減少晶界缺陷。實驗結果顯示，以 n-GaN 基板製備的鈣鈦礦發光二極體(PeLED)，在 3.00 V 的操作電壓下，其輝度與電流效率分別達到141300 cd/m2與20.53 cd/A，電流效率較 ITO 結構大幅提升近10000%。 為進一步提升薄膜結晶品質，本研究延續實驗室先前的熱退火溫度，針對不同退火時間進行調整。結果顯示，於350°C 下退火50 minutes能驅使薄膜由單斜晶相轉變為立方晶相，且晶粒尺寸由 25.44 nm 成長至38.69 nm，顯著增加了 62%。證實退火能夠改善晶界缺陷，並促使晶粒相互吞併生長。此外，為了確定主動層厚度對元件載子傳輸平衡的影響，本研究針對主動層厚度進行調整。當厚度調整至最佳500 nm時，不僅解決了薄膜過薄導致載子復合空間不足的限制，同時避免厚度過厚導致元件內阻上升。藉由退火參數與主動層厚度改善，元件的最大輝度與電流效率分別提升至262700 cd/m2與32 cd/A，相較未退火元件分別提升86%、56%。 最後為了克服CsPbBr3激子束縛能較低之限制，導入類量子阱結構。透過多源順序交替沉積(CsBr+CsPbBr3)，成功生成二維Cs4PbBr6作為能障。當結構為4對並結合最佳退火製程時，載子侷限達到最佳平衡。在3.19V驅動電壓下達到最大輝度438700 cd/m2，電流效率 39.57 cd/A，外部量子效率(EQE)15.51%。相較無類量子阱結構的元件，輝度與電流效率分別提升67%、24%。在大氣環境運作穩定性測試中，n-GaN基板憑藉Sapphire的高導熱性有效緩解了元件的熱淬滅，使其T50運作壽命達到77.92 minutes，相較於 ITO 結構元件的33.67 minutes顯著提升了131%。綜上所述，本研究證實了 n-GaN基板上能夠製作出高品質鈣鈦礦薄膜，同時搭配類量子阱結構設計與退火製程的改善，能夠製備出高品質PeLED。;To overcome the bottlenecks of poor thermal conductivity and large energy barriers associated with conventional indium tin oxide (ITO) electrodes， this study utilizes wide-bandgap n-GaN to replace the ITO electrode. Based on energy-level alignment and high electron mobility analysis， the n-GaN substrate significantly reduces the electron injection barrier while providing an excellent hole-blocking function to effectively confine carriers. Microscopic analyses via XRD， HR-TEM， and SAED further confirm that in the unannealed state of CsPbBr3， the polar surface and flat morphology of n-GaN effectively induce a geometric alignment between the CsPbBr3 (002) plane and the GaN (0002) plane. This behavior facilitates oriented crystalline growth， suppresses randomized nucleation， and substantially mitigates grain boundary defects， which contrasts sharply with the randomized growth and disordered lattices observed on the ITO substrate. Experimental results demonstrate that the perovskite light-emitting diode (PeLED) fabricated on the n-GaN substrate achieves a luminance of 141300 cd/m2 and a current efficiency of 20.53 cd/A under an operating voltage of 3.00 V; notably， the current efficiency represents an approximate 10000% enhancement compared to that of the ITO-based structure. To further improve the film crystallization， this study adopts the thermal annealing temperature previously established in our laboratory and systematically adjusts the annealing duration. The results indicate that annealing at 350 degrees Celsius for 50 minutes drives a phase transition in the film from a monoclinic phase to a cubic phase. Concurrently， the grain size grows from 25.44 nm to 38.69 nm， representing a significant increase of 62%， which confirms that annealing can mitigate grain boundary defects and promote grain growth through coalescence. Furthermore， to determine the impact of active layer thickness on the carrier transport balance of the device， the thickness of the active layer was optimized. When the thickness is adjusted to the optimal value of 500 nm， it not only overcomes the limitation of insufficient carrier recombination space in overly thin films but also avoids the increase in device internal resistance caused by excessive thickness. Through the synergistic optimization of annealing parameters and active layer thickness， the maximum luminance and current efficiency of the device are elevated to 262700 cd/m2 and 32.00 cd/A， yielding improvements of 86% and 56%， respectively， compared to the unannealed counterpart. Finally， to circumvent the limitation of the low exciton binding energy of CsPbBr3， a quasi-quantum well structure was introduced. Through multi-source sequential alternating deposition (CsBr + CsPbBr3)， two-dimensional Cs4PbBr6 was successfully generated as potential barriers. When the structure consists of 4 pairs coupled with the optimized annealing process， the carrier confinement reaches an optimal balance. Under a driving voltage of 3.19 V， the device achieves a maximum luminance of 438700 cd/m2， a current efficiency of 39.57 cd/A， and an external quantum efficiency (EQE) of 15.51%. Compared to the device without the quasi-quantum well structure， the luminance and current efficiency are further enhanced by 67% and 24%， respectively. In ambient operational stability tests， leveraging the high thermal conductivity of the sapphire substrate， the n-GaN based platform effectively alleviates the thermal quenching of the device， extending its T50 operational lifetime to 77.92 minutes， which is a significant 131% increase compared to the 33.67 minutes of the ITO-structured device. In summary， this study confirms the feasibility of fabricating high-quality perovskite thin films on n-GaN substrates. Combined with the quasi-quantum well structural design and the refinement of annealing processes， high-performance PeLED have been successfully realized.
