現今業界多半使用金屬氣相沉積法(Metal-organic Chemical Vapor Deposition，MOCVD)以及分子束磊晶(Molecular beam epitaxy，MBE)兩種方式磊晶氮化鎵(Gallium Nitride，GaN)薄膜，但因為兩種製程方式之工作溫度接近或超過1000˚C，考量到基板與薄膜的熱膨脹係數不同，高溫製程容易使磊晶的薄膜在降溫的過程中產生裂紋、翹曲等情況，並且MOCVD以及MBE在磊晶氮化鎵薄膜時，均具有使用有毒氣體和低鍍率的問題。 本研究利用高能脈衝磁控濺鍍(High Power Impulse Magnetron Sputtering，HiPIMS)的製程方式磊晶氮化鎵薄膜於矽基板上，避免使用毒性物質，並提升濺鍍速率，透過高能量且高密度的電漿生長磊晶氮化鎵薄膜，將達到降低製程溫度、提高鍍率、使用非毒性氣體的方式進行研究。 在研究過程中，固定製程溫度為500˚C，改變放能時間(On time)、佔空比(Duty cycle)、氣體流量、偏壓等參數，透過X光繞射儀(X-ray Diffractometer，XRD)分析結晶強度和晶格峰值半高寬(Full Width at Half Maximum，FWHM)、掃描式電子顯微鏡(Scanning Electron Microscopy，SEM)分析薄膜厚度及表面生長狀況、原子力顯微鏡(Atomic Force Microscopy，AFM)分析粗糙度、光電子能譜儀(X-ray Photoelectron Spectroscopy，XPS)分析薄膜的元素組成成份、穿透式電子顯微鏡(Transmission Electron microscopy，TEM)分析晶格排列及缺陷情況。最後，本研究成功利用低溫高能脈衝磁控濺鍍在矽基板上磊晶出具有高結晶度的氮化鎵薄膜。 ;Metal-organic chemical vapor deposition(MOCVD) and molecular beam epitaxy(MBE) have been applied to deposit epitaxial gallium nitride(GaN) thin films in the industry. The process temperatures on MOCVD and MBE were approached to or than 1000˚C. Considering the thermal expansion coefficient in between the substrate and the GaN film, the higher process temperature the more cause cracks and warpage happened on the epitaxial film. Beside, MOCVD and MBE have the problems of using toxic gas and low depositing rate when fabricating the GaN films. In this study, a high power impulse magnetron sputtering(HiPIMS) has been useds to fabricate epitaxial GaN films on Si substrate without toxic substances during the sputtering and high depositing rate. The high-energy and high-density plasma during the HiPIMS process, decrease the process temperature and increas the depositing rate without the toxic gases. The process temperature was fixed at 500˚C, the on-time, duty cycle, gas flow, and bias voltage were varied. X-ray diffractometer(XRD) has been applied to analyze crystalline strength and lattice peak full-width at half-width(FWHM), scanning electron microscope(SEM) to analyze film thickness and surface growth conditions, atomic-force microscopy(AFM) to analyze the surface roughness, photoelectron spectroscopy(XPS) to analyze the elemental composition of the films, transmission electron microscopy(TEM) to analyze the crystallinity grid arrangement and defects. Finally, the epitaxial GaN thin films have been fabricated on the Si substrate by using HiPIMS with low process temperature successfully.
