ontents 3. Generation/Recombination Phenomena., 31. Introduction 3.2. Direct and indirect transitions. 74 3.3. Generation/recombination centers 3.4. Excess carrier lifetime 3.5. SRH recombination 82 3.5.1. Minority carrier lifetime 3.6. Surface recombination Important Equations……………,… Problems 4. The pn Junction Diode ∴95 41. Introduction 4.2. Unbiased PN junction. 4.3. Biased PN junction... 103 44. Current-voltage characteristics 4.4 1. Derivation of the ideal diode model 107 4.4.2. Generation/recombination current 4.3. Junction breakdown....... 4.4.4. Short-base diode 118 4.5. PN junction capacitance. 4.5.1. Transition capacitance 120 4.5.2. Diffusion capacitance…… 4.5.3. Charge storage and switching time 123 4.6. Models for the PN junction 4.6. 1. Quasi-static, large-signal model 4.6.2. Small-signal, low-frequency model 4.6.3. Small-signal, high-frequency model 47. Solar cell 128 4. 8. pin diode .133 5. Metal-semiconductor contacts 5.1. Schottky diode 139 5.1.1. Energy band diagram.. 5.1.2. Extension of the depletion region 5.1.3. Schottky effect 143 5.1.4. Current-voltage characteristics 145 5.1.5. Influence of interface states 146 5.1.6. Comparison with the PN junction. 147 5.2. Ohmic contact Important Equations……… Problems 151vi Contents 3. 3.1. 3.2. 3.3. 3.4. 3.5. 3.5.1. 3.6. 4. 4.1. 4.2. 4.3. 4.4. 4.4.1. 4.4.2. 4.4.3. 4.4.4. 4.5. 4.5.1. 4.5.2. 4.5.3. 4.6. 4.6.1. 4.6.2. 4.6.3. 4.7. 4.8. 5. 5.1. 5.1.1. 5.1.2. 5.1.3. 5.1.4. 5.1.5. 5.1.6. 5.2. Generation/Recombination Phenomena Introduction Direct and indirect transitions Generation/recombination centers Excess carrier lifetime SRH recombination Minority carrier lifetime Surface recombination Important Equations Problems The PN Junction Diode Introduction Unbiased PN junction Biased PN junction Current-voltage characteristics Derivation of the ideal diode model Generation/recombination current Junction breakdown Short-base diode PN junction capacitance Transition capacitance Diffusion capacitance Charge storage and switching time Models for the PN junction Quasi-static, large-signal model Small-signal, low-frequency model Small-signal, high-frequency model Solar cell PiN diode Important Equations Problems Metal-semiconductor contacts Schottky diode Energy band diagram Extension of the depletion region Schottky effect Current-voltage characteristics Influence of interface states Comparison with the PN junction Ohmic contact Important Equations Problems 73 73 74 77 79 82 86 87 89 89 95 95 97 103 105 107 113 116 118 120 120 121 123 125 126 126 128 128 132 133 133 139 139 139 142 143 145 146 147 149 150 151