以溶凝膠法製備鈦酸鍶鋇薄膜之電學及光激光特性分析

Abstract

本研究以溶凝膠法製備鈦酸鍶鋇薄膜電容，變化不同的製程條件，包括不同的退火溫度及退火時間，並經由電容—電壓、電流—電壓、X-光繞射及掃描式電子顯微鏡等量測結果，研究製程條件對薄膜的漏電流、介電常數、介電損失及結晶性的影響，以求得一最佳化之製程條件，並由所得的電流—電壓圖來判斷其室溫下的漏電流機制。 另方面，將鉺離子摻雜在鈦酸鍶鋇薄膜中，變化不同的鉺離子摻雜濃度及退火溫度，研究其光激光特性，討論不同退火溫度及鉺離子摻雜濃度對光激光強度的影響，求得有最強的光激光強度之最佳化之製程條件，並找出光激光強度衰退的原因及機制。

Sol-gel derived BST thin films were prepared under various process parameters including annealing temperature and time. The effects of processing parameters on leakage current, dielectric constant, dielectric loss and crystallinity were studied through C-V, I-V, XRD and SEM measurements. Then the optimum processing parameters were found for BST thin film capacitors on the basis of experimental results. Two conduction mechanisms of the leakage current, Schottky emission and Poole-Frenkel emission, at room temperature were studied. The Er-doped BST thin films deposited on silicon substrate were fabricated under various processing parameters such as annealing temperature, annealing time and concentration of Er). The photoluminescent spectra of those Er-doped thin films were studied. The optimum processing parameters of Er-doped thin films which have the strongest PL intensity were determined. The degradation mechanisms of PL intensity of the films were also studied