利用溶膠凝膠法在具有氧化鎂緩衝層之矽基板上製備高C軸優選方向鋯鈦酸鉛薄膜及其在表面聲波元件之應用

Preparation of Highly C-axis Oriented PZT Films on Si Substrate by Sol-Gel Method with MgO Buffer Layer and Their Surface Acoustic Wave Applications

顏志中(Zhi-Zhung Yen)

指導教授 ： 施文欽

大同大學/電機資訊學院/光電工程研究所/碩士(2007年)

摘要

將PZT 薄膜沉積於Si 基板上是非常困難的，主要由於兩者晶格常數的不匹配以及在高溫沉積時相互間的擴散問題。在本研究中，我們研究MgO 緩衝層與不同退火條件下對於利用溶膠凝膠法製程之PZT 薄膜於Si 基板上的影響。實驗結果顯示，將PZT薄膜成長於MgO/Si 基板上在退火溫度600 0C 持溫 1 小時可以得到高C軸方向薄膜。其PZT 薄膜C軸的優選方向PZT(001)與PZT(002)之半高寬分別為0.18˚ 與 0.22˚，並以AFM 測量其表面平坦度為 3.9 nm，嘗試製備交指狀換能器於PZT薄膜上，準備兩種不同架構之基材，並利用網路頻譜分析儀量測，以利於爾後PZT薄膜之表面聲波元件應用與發展，這個結果在往後的研究有助於將鐵電元件與半導體元件整合於同一塊Si 基板上。

關鍵字

鋯鈦酸鉛 ； 氧化鎂 ； 鎳酸鑭 ； 表面聲波元件

並列摘要

Lead zirconate titanate (Pb(Zr,Ti)O3, PZT) thin films have received much attention due to their excellent dielectric, ferroelectric and piezoelectric properties. Epitaxial growth of PZT films on Si substrate is desirable to integrate ferroelectric devices and semiconductor devices on the same substrate. However, epitaxy of PZT films directly on Si substrates is very difficult because of the lattice mismatch between them and the interdiffusion owing to the high growth temperature during deposition. In this research, we study the effect of MgO buffer layer and the post-annealing conditions on the C-axis orientation of the PZT films fabricated by the sol-gel method on Si substrate. The experimental results show that if we anneal the PZT films grown on MgO (200)/Si substrate at 600 °C for 1 hour, highly C-axis oriented PZT films could be obtained. The full width at half maximum intensity (FWHM) of PZT (001) and PZT (002) peaks obtained from the X-ray diffraction (XRD) were 0.18 ° and 0.22 °, respectively. The surface roughness of the annealed PZT films was about 3.9 nm. Preparing two kinds of the structure, We try to fabricate the interdigital transducer (IDT) on PZT films and measure the frequency response by network analyzer. The results could be useful in the integration of ferroelectric devices and semiconductor devices on the same Si substrate.

並列關鍵字

PZT ； MgO ； SAW ； LNO

參考文獻

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