非揮發性記憶體寫入資料，即不需外界電力來維持其記憶，且其低功耗的特點，更適合作為使用電池的攜帶型電子產品。目前所使用之非揮發性記憶體，其製程需長時間的高溫熱處理，這對產能和製造費用都是一項負擔，因此降低製程溫度是絕對必要的趨勢。而近來有利用超臨界二氧化碳流體之氧化處理法，可有效降低熱處理製程溫度。本論文利用傳統熱退火以及超臨界二氧化碳製成非揮發性記憶元件並分析其特性。
本論文使用Zn與Sn和SiO2之混合層，來降低製程溫度，並利用氧化鋅與氧化錫本身缺陷作電荷儲存之浮閘層，來製作奈米薄膜非揮發性記憶體。鋅和錫係理論上作為低熔點金屬模型材料，為確定Zn和Sn的共鍍之產物是否能成功製作奈米材料元件，首先利用一般傳統的快速熱退火技術製作。在矽晶圓穿隧氧化層上沈積共鍍Zn+Sn+SiO2的薄膜，在後續不同溫度的熱處理狀況下使奈米氧化鋅與氧化錫析出，再藉由電容-電壓(C-V)量測來分析其電性及材料性質的變化。當電子注入奈米薄膜氧化層之後，元件之起始電壓會發生偏移，此偏移的量即定義為記憶體元件的記憶窗，即確認有奈米結構非揮發性記憶體元件的特性。本論文利用超臨界二氧化碳流體技術，研究儲存層中不同的鋅、錫摻雜含量之記憶效應和CV電性分析以及DLTS分析此儲存層缺陷特性、電荷儲存能力。實驗證實無論電荷是從閘極注入亦或穿隧氧化層注入，其深淺缺陷之峰值的位置皆相同，且超臨界二氧化碳流體製程鋅與錫合金具有明顯記憶特性，發現鋅有助於氧化錫深能階缺陷之儲存能力。DLTS發現有一新的species存在0.93 eV處，具有較低之活化能，加強電荷儲存能力。由XPS與DLTS分析得知不同Zn、ZnO、Zn-O-Si與Sn、SnO深能階缺陷形成電荷儲存機制。證明本論文所提出的鋅與錫合金之超臨界二氧化碳流體製程是有前瞻性的，以低溫製程特性佳之奈米點記憶體元件。

Non-volatile memory can keep the data without supplying power, and it is suitable for portable electronic products due to the advantage of low power consumption. In current industrial production, high-temperature and long-time process are necessary for the fabrication of non-volatile memory, which are heavy loadings on production capacity and lots cost. Therefore, decreasing the temperature of the process is a trend. Recently using the oxidation treatment of supercritical carbon dioxide fluid can efficiently decrease the temperature of the process.
In this thesis, the mixture layer of Zn, Sn, and SiO2 is applied to reduce the temperature of process, and to employ the defects of ZnO and SnO2 as floating gate for electron storage to fabricate the nonvolatile memory device. Zn and Sn are applied due to the low temperature melting points. To ensure the layer of cosputtering with Zn and Sn to be able to successfully fabricate as nano material device, the process of traditional rapid temperature annealing treatment was applied for first step.
The co-sputtered Zn-Sn-SiO2 thin film was deposited on the tunneling oxide layer, and then the thin film was treated with varied annealing temperature to precipitate ZnO and SnO2 nanocrystals. After that, the C-V measurement is applied to analyze the change of the electrical and material properties. Using a positive bias, the electrons are injected into the oxide layer, by the threshold voltage the offset is occurred, which is defined as the memory window of the memory effect, and the property of nonvolatile memory will be applied. In addition, no matter the charge is injected from the gate oxide or tunnel oxide, the defects position of DLTS’s peak is with the same property.
The supercritical carbon dioxide fluid technology has been performed to study the memory effect. The capability of electron injection, storages and the defect, in the storage layer were studied by the C-V measurement and DLTS. The experiment confirmed that the Zn-Sn alloy has the memory property after it been treated by the supercritical carbon dioxide fluid technology. It has shown that Zn can promote to the storage capability ability due to the formation of deep level defects of SnO2 from the DLTS spectra. A new species is found at 0.93 eV with low activation energy and high capability of electron storage. The defect formation mechanism of Zn, ZnO, Zn-O-Si, Sn, and SnO are analyzed by found by the XPS and DLTS. The device fabrication using Zn-Si alloy and supercritical carbon dioxide fluid technology has the potential to reduce the process temperature and to improve the memory property of nonvolatile memory device.

致謝 i
中文摘要 ii
Abstract iii
目錄 v
表目錄 vii
圖目錄 viii
第一章 緒論 1
1.1 前言 1
1.2 非揮發性記憶體介紹 3
1.3 超臨界二氧化碳介紹 6
第二章 能帶理論與深能階暫態能譜原理 10
2.1 非揮發性記憶體工作原理 10
2.1.1. 快閃記憶體之寫入與抹除原理 10
2.1.2. 穿隧機制 10
2.2 深能階暫態能譜量測原理 12
2.2.1. Shockley-Read-Hall 復合理論[34] 13
2.2.2. 脈衝電壓與介面缺陷行為 15
2.2.3. 缺陷參數決定 15
第三章 實驗:鋅錫之非揮發性記憶體元件之製作及分析 22
3.1 鋅錫之記憶體元件之製作 22
3.2 深能階暫態頻譜量測 24
第四章 結果與討論 30
4.1 二氧化矽缺陷研究 30
4.1.1 退火溫度對二氧化矽缺陷影響 31
4.1.2 超臨界二氧化碳處理對二氧化矽缺陷影響 31
4.2 奈米薄膜儲存特性研究 32
4.2.1 退火溫度對記憶效應影響 32
4.2.2 鋅錫比例對記憶效應影響 33
4.2.3 超臨界二氧化碳處理製作奈米點 34
4.3 以深能階暫態頻譜研究缺陷儲存機制 35
第五章 結論 71
第六章 參考資料 72

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