臺灣博碩士論文加值系統

具全寫入機制電荷儲存式的鰭式複晶矽奈米線穿隧電晶體非揮發性記憶體是第一次被研究實現，且可以展現大的記憶窗以及優質的可靠度。
鰭式奈米線架構可提供快速的寫入/抹除操作。除此之外，電荷離散儲存式架構也更加優化可靠度特性。不僅如此，由於具有複晶矽形成之通道，使本研究有機會應用於未來高密度三維堆疊的非揮發性記憶體領域。
在FN tunneling寫入的情形下，所有的操作機制包含傳導電流機制和記憶體寫入/抹除機制全部都建立於量子穿隧傳輸，並且擁有不錯的記憶窗(在Vg = 17V, tp = 1ms條件下，記憶窗可達4.75V)，以及優秀的88 %忍耐度和處於85 oC高溫的惡劣環境下維持65 %儲存10年的能力。在CHE寫入的情形下，本研究可展現大的記憶窗(在Vg = 8V, Vd = 6V, tp = 1ms條件下，記憶窗可達4V)，以及不錯的74 %忍耐度。更重要的是處於85 oC高溫的惡劣環境下，可維持極好81 %的儲存10年能力。在BBHE寫入的情形下，本研究利用極低寫入電壓條件即可展現極大的記憶窗(在Vg = 3V, Vd =-6V, tp = 1ms小電壓條件下，記憶窗即可達4V)，以及不錯的74 %忍耐度和處於85 oC高溫的惡劣環境下維持63 %的儲存10年能力。
根據上述所提到的描述，電荷儲存式的鰭式奈米線穿隧電晶體非揮發性記憶體擁有低靜態功率消耗和低寫入電壓特性，所以非常有潛力被應用於未來高密度三維堆疊的手持式產品之中。

The Pi-gate polycrystalline silicon (poly-Si) nanowires tunneling field effect transistor (TFET) charge trapping(CT) nonvolatile memory (NVM) with all programming mechanisms and shows a large memory window and good reliability is demonstrated for the first time.
Pi-gate nanowires structure performs faster program/erase speed. Otherwise, the SONOS-type structure can improve excellent reliability. Furthermore, due to the poly-Si channel technology, it is possible to develop in 3D high-density stacked NVM.
In FN tunneling programming, operation of conducting current and program/erase are based on all quantum tunneling transportation. Pi-gate T-SONOS NVM generates a large memory window (ΔVth=4.75V at Vg = 17V, tp = 1ms) and excellent reliability of 88 % endurance behavior after 10k P/E cycles and 65 % retained ability for ten years at 85 oC. In CHE programming, Pi-gate T-SONOS NVM presents a large memory window (ΔVth=4V at Vg=8V, Vd=6V, tp=1ms), and 74 % endurance behavior after 10k P/E cycles. Moreover, a superior 81 % retention behavior for ten years at 85 oC is presented. In BBHE programming, Pi-gate T-SONOS NVM performs a high programming efficiency, larger memory window (ΔVth=4V at Vg=3V, Vs=-6V, tp=1ms), excellent reliability of 74 % endurance after 10k P/E cycles and 63 % retention for ten years at 85 oC can be achieved.
Based on above-mentioned description, Pi-gate nanowires T-SONOS NVM is suitable to use in future 3D high-density embedded portable applications with low stand-by power consumption and ultra low program voltage.

中 文 摘 要 i
Abstract iii
Acknowledge v
Contents vii
Table Captions x
Figure Captions xi
Chapter 1 Introduction 1
1.1 Tunneling-Field-Effect-transistor (TFET) 1
1.2 Introduction of Nonvolatile Memory 3
1.2.1 Historical Perspective to Nonvolatile Memory 3
1.2.2 The SONOS NVM 5
1.3 The Multi-Gate Structure with nanowires 6
1.4 The 3D development of Poly-Si Channel 7
1.5 Motivation 8
1.6 Thesis Organization 9
Chapter 2 Basic Mechanisms and Reliability of Nonvolatile Memory 17
2.1 Basic Mechanisms of Nonvolatile Memory 17
2.1.1 Introduction 17
2.1.2 Program Mechanism 17
2.1.2.1 Fowler-Nordheim (FN) Tunneling 17
2.1.2.2 Channel Hot-Electron (CHE) Injection 18
2.1.2.3 Band-To-Band Tunneling Induced Hot Electron (BBHE) Injection 19
2.1.3 Erase Mechanism 20
2.1.3.1 Fowler-Nordheim (FN) Tunneling 20
2.1.3.2 Edge Fowler-Nordheim (FN) Tunneling 20
2.1.4 Program/Erase Speed 21
2.2 Basic Reliability of Nonvolatile Memory 21
2.2.1 Endurance 21
2.2.2 Retention 21
Chapter 3 Device Fabrication and Simulation 32
3.1 Device Structure and Fabrication 32
3.2 Simulation of Pi-gate Structure 33
Chapter 4 Characteristics of Pi-gate Nanowires Tunnel-FET SONOS Nonvolatile Memory with All Programming Mechanisms 41
4.1 Introduction 41
4.2 FN-Tunneling Programming 42
4.2.1 Simulation of FN-Tunneling Mechanism Band Diagram 42
4.2.2 Id-Vg Characteristic 42
4.2.3 Program/Erase Characteristics 43
4.2.4 Reliability of Data Endurance 44
4.2.5 Reliability of Data Retention 44
4.3 Channel Hot-Electron (CHE) Injection Programming 48
4.3.1 Id-Vg Characteristic 48
4.3.2 Program/Erase Characteristics 48
4.3.3 Reliability of Data Endurance 49
4.3.4 Reliability of Data Retention 49
4.4 Band-To-Band Tunneling Induced Hot Electron (BBHE) Injection Programming 53
4.4.1 Simulation of BBHE Mechanism Band Diagram 53
4.4.2 Id-Vg characteristic 53
4.4.3 Program/Erase characteristics 54
4.4.4 Reliability of Data Endurance 54
4.4.5 Reliability of Data Retention 55
4.5 Performance Comparison of Pi-gate T-SONOS NVM with FN-tunneling, CHE and BBHE Program Mechanisms 59
Chapter 5 Conclusion 61
Reference 62

Chapter 1

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Chapter 2

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Chapter 3

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Chapter 4

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