研究生: |
黎孟琦 Li, Mong-Chi |
---|---|
論文名稱: |
介面層經熱與氫氣處理對純鍺金氧半電晶體之特性影響研究 Interfacial Layers with Thermal and Hydrogen Treatments on Characteristics of Germanium MOSFETs |
指導教授: | 張廖貴術 |
口試委員: |
趙天生
張宗生 |
學位類別: |
碩士 Master |
系所名稱: |
原子科學院 - 工程與系統科學系 Department of Engineering and System Science |
論文出版年: | 2014 |
畢業學年度: | 102 |
語文別: | 中文 |
論文頁數: | 96 |
中文關鍵詞: | 鍺金氧半電晶體 、鍺氧化層 、介面工程 、氫氣處理 、熱處理 、微波退火活化 |
相關次數: | 點閱:2 下載:0 |
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摘要
本論文研究以ALD的水氣電漿做為沉積介面層的主要製程,以得到高品質的GeO2及良好電特性為研究主軸。分別探討熱處理的影響及氫氣界面修補。最後則是將氫氣處理及脫附機制的參數製作電晶體,並搭配微波退火優化元件特性。
熱處理方面使用沉積後退火搭配燒結製程能提供熱能使原子重新排列,轉變介電層結晶成 cubic phase有效形成較低EOT,同時維持漏電在100 A/cm2。然而,對於物理厚度 3 nm的薄膜,則以簡單的sinter處理能有效的達到良好的EOT及元件電性。
氫氣處理部分,在低溫下氫氣能有效與不穩定的GeOx反應,形成Ge及H2O水氣,排除GeOx減少Ge1+形成更多的Ge4+,形成最薄的EOT ~0.5 nm,同時漏電流維持在100 A/cm2。特別在frequency dispersion及變頻量測的Dit上可以明顯觀察到,低溫氫氣處理可以修補介面缺陷,使Dit達1011 eV-1cm-2。
最後則是延伸以往最佳參數製備Ge PMOSFET,並進一步將最好參數應用在微波退火。其中,氫氣的介面優化可以改善閘極控制電流能力,使得元件Gm有效提升,並壓低元件的S.S.。另一方面,微波退火處理後,改善PN接面特性,使元件的截止電流有效壓低。因此,氫氣微波退火後的電晶體導通電流比截止電流大約三個數量級,同時元件Gm高達3000 μA/V,並將S.S.下壓到160 mV/dec。另一方面,其載子遷移率可以高達471 cm2/V-s,反轉電容可仍然維持在3.5 μF/cm2,對應EOT則達到0.55 nm。以此氫氣處理搭配微波退火為最佳電晶體製程條件。
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