Preface |
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viii | |
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1 | (17) |
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1.1 Introduction to quantum mechanics |
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1 | (12) |
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1.1.1 The double slit experiment |
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1 | (3) |
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1.1.2 Basic concepts of quantum mechanics |
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4 | (6) |
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1.1.3 Schrodinger's equation |
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10 | (3) |
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1.2 Basic quantum physics problems |
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13 | (5) |
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13 | (1) |
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1.2.2 Particle in a one-dimensional box |
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14 | (3) |
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17 | (1) |
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18 | (21) |
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2.1 Understanding tunnelling |
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18 | (5) |
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2.1.1 Qualitative description |
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18 | (2) |
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2.1.2 Rectangular barrier |
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20 | (3) |
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23 | (3) |
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2.3 Landauer's tunnelling formula |
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26 | (3) |
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2.4 Advanced tunnelling models |
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29 | (10) |
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2.4.1 Non-local tunnelling models |
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30 | (1) |
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2.4.2 Local tunnelling models |
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30 | (8) |
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38 | (1) |
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39 | (39) |
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39 | (3) |
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3.1.1 The need for tunnel FETs |
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39 | (2) |
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3.1.2 Basic TFET structure |
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41 | (1) |
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3.2 Qualitative behaviour |
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42 | (21) |
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42 | (10) |
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3.2.2 Device characteristics |
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52 | (7) |
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3.2.3 Performance dependence on device parameters |
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59 | (4) |
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63 | (11) |
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63 | (7) |
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3.3.2 Three-dimensional TFETs |
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70 | (2) |
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3.3.3 Carbon nanotube and graphene TFETs |
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72 | (1) |
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3.3.4 Point versus line tunnelling in TFETs |
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73 | (1) |
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3.4 Other steep subthreshold transistors |
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74 | (4) |
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74 | (4) |
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4 Drain current modelling of tunnel FET: the task and its challenges |
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78 | (12) |
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78 | (3) |
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4.2 TFET modelling approach |
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81 | (6) |
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4.2.1 Finding the value of ψC |
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82 | (1) |
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4.2.2 Modelling the surface potential in the source--channel junction |
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83 | (2) |
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4.2.3 Finding the tunnelling current |
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85 | (2) |
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4.3 MOSFET modelling approach |
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87 | (3) |
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89 | (1) |
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5 Modelling the surface potential in TFETs |
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90 | (50) |
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91 | (7) |
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5.1.1 Parabolic approximation of potential distribution |
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91 | (3) |
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5.1.2 Solving the 2D Poisson equation using parabolic approximation |
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94 | (1) |
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5.1.3 Solution for the surface potential |
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95 | (3) |
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5.2 The variational approach |
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98 | (9) |
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5.2.1 The variational form of Poisson's equation |
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99 | (2) |
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5.2.2 Solution of the variational form of Poisson's equation in a TFET |
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101 | (6) |
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5.3 The infinite series solution |
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107 | (12) |
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5.3.1 Solving the 2D Poisson equation using separation of variables |
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107 | (2) |
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5.3.2 Solution of the homogeneous boundary value problem |
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109 | (3) |
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5.3.3 The solution to the 2D Poisson equation in a TFET |
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112 | (2) |
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5.3.4 The infinite series solution to Poisson's equation in a TFET |
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114 | (5) |
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5.4 Extension of surface potential models to different TFET structures |
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119 | (12) |
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119 | (3) |
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122 | (3) |
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5.4.3 Dual material gate TFET |
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125 | (6) |
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5.5 The effect of localised charges on the surface potential |
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131 | (1) |
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5.6 Surface potential in the depletion regions |
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132 | (3) |
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5.7 Use of smoothing functions in the surface potential models |
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135 | (5) |
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137 | (3) |
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6 Modelling the drain current |
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140 | (23) |
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142 | (5) |
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6.1.1 Landauer's tunnelling formula in TFETs |
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142 | (1) |
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6.1.2 WKB approximation in TFETs |
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143 | (1) |
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6.1.3 Obtaining the drain current |
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144 | (3) |
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147 | (10) |
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6.2.1 Numerical integration |
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148 | (1) |
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6.2.2 Shortest tunnelling length |
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148 | (2) |
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6.2.3 Constant polynomial term assumption |
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150 | (2) |
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6.2.4 Tangent line approximation |
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152 | (5) |
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6.3 Threshold voltage models |
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157 | (6) |
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6.3.1 Constant current method |
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158 | (1) |
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6.3.2 Constant tunnelling length |
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159 | (1) |
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6.3.3 Transconductance change (TC) method |
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160 | (1) |
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161 | (2) |
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7 Device simulation using ATLAS |
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163 | (18) |
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7.1 Simulations using ATLAS |
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164 | (7) |
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165 | (1) |
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7.1.2 Structure specification |
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166 | (3) |
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7.1.3 Material parameters and model specification |
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169 | (1) |
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7.1.4 Numerical method specification |
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170 | (1) |
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7.1.5 Solution specification |
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170 | (1) |
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7.2 Analysis of simulation results |
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171 | (3) |
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174 | (7) |
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180 | (1) |
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181 | (13) |
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181 | (7) |
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8.2 Other tunnelling models |
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188 | (2) |
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8.2.1 Schenk band-to-band tunnelling model |
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188 | (1) |
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8.2.2 Non-local band-to-band tunnelling |
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188 | (2) |
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8.3 Gate all around nanowire TFET |
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190 | (4) |
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193 | (1) |
Index |
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194 | |