脈衝雷射蒸鍍法製備氧化鏑鋅薄膜的探討： 結構、光學與磁性研究

Abstract

利用脈衝雷射沉積法製備摻雜鏑的氧化鋅薄膜，鏑的原子莫耳濃度介於1~10%之間。在氧氣壓力3×10-1mbar的鍍膜條件下，X光繞射顯示樣品維持原有的晶體結構，沒有雜質態產生。因為薄膜的厚度只有150nm左右，拉曼散射光譜只獲得微弱的訊號。純氧化鋅PL光譜只有本質激發，缺陷發光是Dy摻雜造成，多為鋅空缺及鋅間隙。有摻雜Dy的薄膜在室溫皆具有鐵磁性，低溫(5K)則為順磁性。Dysprosium doped ZnO (Zn1-xDyxO) thin films were grown on c-sapphire by pulsed-laser deposition. The nominal Dy concentration is between 1 and 10 at%. The oxygen pressure of crystal growth is 3×10-1mbar and the thickness of thin films is 150nm. X-ray diffraction patterns show that there is no secondary phase. No distinguishable ZnO oscillation mode was observed from Raman-scattering spectroscopy because the thickness of the thin films is only 150nm. Photoluminescence spectroscopy of pure ZnO shows only emissions from band gap. Increasing in defect emissions as Dy concentration increases. The major defects are zinc vacancy and interstitial zinc. Room temperature m-H curves show hysteresis loops for all Dy doped samples. The low temperature (5K) m-H curves show only paramagnetism.