傳統的浮停閘快閃記憶體是利用連續的多晶矽半導體薄膜作為載子儲存的單元，而在元件尺寸持續微縮下此結構將面臨一些瓶頸，為了克服瓶頸因而衍生出兩種非揮發性記憶體結構：一種是SONOS非揮發性記憶體，另一種是奈米晶體（量子點）非揮發性記憶體。
在本論文中，主要在探討將記憶體元件製作在類似玻璃基板上的特性，透過學長先前製作多重奈米線通道(multiple nanowire channel)之複晶矽薄膜電晶體(poly-Si TFTs)的經驗，SONOS非揮發性記憶體將與複晶矽薄膜電晶體互相整合，而製作具有奈米線之非揮發性記憶薄膜電晶體(Nonvolatile SONOS TFT memory with Nano-wire structure)，由於十條奈米線通道之元件具有較優越與較穩定的電特性，論文內容主要針對一條通道且其寬度為1μm與十條奈米線通道其每條寬度為65nm之元件的記憶體特性作比較，可以明顯發現十條奈米線結構具有較大的記憶窗，且有比較高的寫入/抹除效率，主要是由於十條奈米線之記憶體元件具有分立奈米線，使得閘極環跨於通道時，形成環繞式的三向閘極(tri-gate)，閘極擁有較佳的控制能力，且閘極與通道形成多處稜角，此處有較強的電場分佈，使得電子較易透過FN-tunneling通過穿隧氧化層而儲存於氮化矽層的缺陷能階內，造成起始電壓的改變，而有記憶體的特性，此技術將有機會被利用在系統面板上。
另外，金屬奈米點的記憶體元件在低溫環境下的製作也將被探討，透過低溫快速熱氧化條件來讓金屬奈米點析出，能夠儲存載子而具有記憶體特性，並且爭對元件之寫入/抹除效率、可靠度做分析，由於是在低溫的環境下被製作，未來將能夠進一步的與薄膜電晶體互相整合。

The conventional floating gate NVSM will suffer some limitations for continued scaling of the device structure. Therefore, two approaches, the silicon-oxide-nitride-oxide-silicon (SONOS) and the nanocrystal nonvolatile memory devices, have been investigated to overcome the limit of the conventional floating gate NVSM.
In this thesis, the SONOS-TFT with multiple nanowires structure was proposed and fabricated for memory applications. The memory characteristic of standard SONOS-TFT, channel width of the device is 1μm, was compared with the nanowires SONOS-TFT, each channel width of the device is 65nm. The SONOS-TFT with multiple nanowires structure (NW SONOS-TFT) has good program/erase efficiency, retention and transfer characteristics due to the larger electric field at the corner region and more number of corners. The NW SONOS-TFTs can be treated as high performance devices and also as high program/erase efficiency nonvolatile memory under adequate voltage range operation. The fabrication of SONOS-TFTs with nano-wire channels is quite easy and involves no additional processes. Such a SONOS-TFT is thereby highly promising for application in the future system-on-panel display applications.
In addition, the metal nanocrystals nonvolatile memory fabricated at low temperature is also studied in this thesis. The Ni-silicide nanocrystals memory was successfully fabricated at low temperature. The rapid thermal oxidation at low temperature was executed to make the metal nanocrystals aggregate. The device has superior memory characteristics, such as program/erase efficiency, retention time and endurance. The nonvolatile metal nanocrystals memory fabricated at low temperature processes is very promising for the application on the portable products and panel displays.

Chapter1 Introduction

1.1. General Background

1.2. SONOS Nonvolatile Memory Devices

1.3. Nanocrystal Nonvolatile Memory Devices

Figures

Chapter2 Basic Mechanisms of Nonvolatile Memory

2.1. Introduction

2.2. Basic Program/Erase Mechanisms

2.2.1 Tunneling Injection

2.2.2 Hot-Electron Injection

2.2.3 Band to Band Assisted Hole Injection

2.3. Basic Reliability of Nonvolatile Memory

2.3.1 Retention

2.3.2 Endurance

2.4. Basic Physical Characteristic of Nanocrystals NVM

2.4.1 Quantum Confinement Effect

2.4.2 Coulomb Blockade Effect

Figures

Chapter3 Novel Nonvolatile SONOS-TFT Memory with Nano-wires Structure

3.1. Motivation

3.2. Experimental Procedures

3.2.1 Device Fabrication

3.2.2 Physical and Electrical Characteristic Analysis

3.3. Results and Discussion

3.3.1 The physical characteristics of SONOS-TFT with multiple nano-wire channels

3.3.2 The Electrical Characteristics of SONOS-TFT with Multiple Nanowire Channels

3.4. Summary I

Figures

Chapter4 Nonvolatile Ni-Silicide Nanocrystals Memory

4.1. Motivation

4.2. Experimental Procedures

4.3. Results and Discussion

4.3.1 Electrical Characteristics

4.3.2 Physical Characteristics

4.3.3 Advanced Electrical Characteristics

4.4. Summary II

Figures

Chapter5 Conclusions

5.1. Conclusions

References

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