在本論文中，我們分別利用有機金屬化學氣相沉積機台(MOCVD)以及濺鍍法(sputter)成長氮化鋁(AlN) Nucleation layer於圖案化藍寶石基板(pattern Sapphire Substrate )上。在不同的AlN Nucleation layer下，透過高解析度 X-光繞射儀(X-ray)、原子力顯微鏡、以及抗靜電測試，觀察其晶格品質。

AFM量測顯示出以濺鍍法成長的薄膜比MOCVD所成長的薄膜均勻性還要好。在XRD的量測中可以觀察到，以濺鍍法成長的AlN Nucleation layer其(002)與(102) 半高寬可以大幅度的減少，綜合AFM與XRD量測結果可以得知，使用濺鍍法成長的AlN Nucleation layer，可以有效的改善GaN發光二極體的磊晶品質。此外，在抗靜電測試中，在反偏600V的測試電流下，濺鍍法成長的AlN Nucleation laye的結構試片還有60%以上的存活率，也就是說濺鍍法來成長AlN Nucleation Layer可以改善成核品質，進而提升抗靜電放電能力。

In this paper, we grew aluminum nitride (AlN) nucleation layer on the patterned sapphire substrates (PSS) using sputter and metal-organic chemical vapor deposition (MOCVD), respectively. We also analyze the crystal qualities of the LEDs with different growth modes of AlN nucleation layer using high resolution X-ray diffraction (X-ray), atomic force microscopy (AFM), and electrostatic discharge (ESD) test.

The AFM results show the AlN nucleation film grown by sputter was more uniform than that grown by MOCVD. In the XRD measurement, it was clearly found that full-width at half-maximum (FWHM) of the (002) and (102) spectra of the LED with sputtered AlN nucleation layer were reduced substantially. According to the AFM and XRD results, it indicates that the crystal quality of GaN was improved by the sputtered AlN nucleation layer. In addition, with 60% survival rate in the ESD test, it was found that the LED with sputtered AlN nucleation layer can endure ESD surges up to −600 V. The enhancement of the ESD endurance of the LED can be attributed to the improvement of overall GaN crystal quality.

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