AL-AZHAR UNIVERSITY FACULTY OF ENGNEERING ELECTRICAL ENGINEERING DEPARTMENT '' Performance Enhancement of Power Transistors and Radiation effect" A THESIS Submitted to AL-AZHAR UNIVERSITY For The Degree of Doctor Philosophy in Electrical Engineering By Eng. Thoraya Abd-El-Magid Ali Hassn M.Sc. (Electrical Power Engineering) Under Supervision of Prof. Dr. El-Said Othman Ass. Prof. Dr. karam Amin Sharshar Prof. of Electrical Power Eng. Chairman of Radiation Eng. Department Dean of faculty of Eng. NCRRT Atomic Energy Authority Al-Azhar University Cairo-Egypt Dr. Shaban Marzok Eladl Radiation Eng.Department NCRRT Atomic Energy Authority Cairo-Egypt Cairo, Egypt 2012 1 ACKNOWLEDGEMENT Praise is to Allah, who guided me to do this work. I would like to thank the spirit of my parents. It is a pleasure to express my sincere gratitude to my supervisors, prof. Dr. S. Othman, Assist prof. Dr. Karam Amin Ali Sharshar, and Dr Shaban. Marzok EL adl for their encouragement and support throughout the thesis. They have never hesitated to spend anytime or effort guide my work. I am very thankful to prof. Dr. S. Othman prof of electrical power Eng. Dean of faculty of Eng. AL-Azhar university for keen supervision, encouragemen, stimulating valuable discussions, during all this work. Deep thanks and gratitude to Assist prof.Dr. Karam Amin Ali Sharsher chairman of radiation Engineering Department for his supervision, encouragement, his helpful discussions, his help in interpreting the results for revising the Manu- script. Then I would like to express my thanks and gratitude to Dr.Shaban Marzok ELadl for his help and his continuous interest the course of this work finally, I would like to thank every person who helped me directly or indirectly. 2 Table of contents PAGE List of Figures………………………………………………………………...................... vi List of Tables………………………………..………………….…………......................... ix List of symbols ……………………………………………………………………………. xi List of Abbreviations……………………………………………......…….......................... xiii ABSTRACT………………………………………………………………......................... xv CHAPTER (I) INTRODUCTION…………………………………………………………………………... 1 1.1 Prior Research….………………………………………………….…………............... 3 1.2Contribution of the Thesis…………………………………….……………................... 17 1.3The thesis is written in five chapters described as follows………..……….…….…….. 17 1.4The aims of the thesis…………………………………………………………….……. 18 CHAPTER (II) OPERATION OF POWER TRANSISTORS………………………………………………….…………………………. 19 2.1 Theoretical Background……………………………………………………………….……. 19 2.1.1 Transistor Basic Structure …………………………………………............................ 19 2.1.2 Bipolar Junction Transistor ………………………………………………………….. 20 2.1.3 Bipolar Junction Transistor under Irradiation ……………….…………...…..…….. 21 2.2 Transistor Application ………………………………………………….………………....... 22 2.2.1 A Simple Application of a Transistor Switch ………………………….…………... 22 2.2.2 Voltage-Divider Biased PNP Transistor ……………………..……..……………… 23 2.2.3 Voltage –divider bias………………………….……………………………….…....... 24 2.2.4 Transistor-based DC Motor Controller (Single Supply) ……...………….……….. 26 2.3 Amplifier Configurations………………………………………….…...…………………… 27 2.3.1 Common-collector transistor Amplifier ………………….……...………………….. 27 2.3.2 Common-Emitter Transistor Amplifier ……………………………………….......... 30 2.3.3 A common-emitter amplifier with voltage-divider bias……..………...………........ 33 2.3.3.1 DC Analysis …………………………………………………………………........... 34 2.3.3.2 AC Equivalent Circuit ……………………………...………….………………....... 35 3 2.3.3.3 Signal (AC) voltage at the Base…………………….…………..……...….….......... 36 2.4 100 Watt Inverter Circuit with the 2N3055Description ………………………………… 38 2.5 NPN BJT Operation …………………………………………..…………………………….. 40 2.5.1 Injection…………………………………………...……………………………............ 41 2.5.2 Diffusion………………………...…………………………………………………..... 42 2.5.3 Collection……….……………………………………………………………………. 43 2.6 Features of the planar epitaxial BJT structure ……………………………………………. 44 2.7 Injection of Holes from base to Emitter…………………………….……………....……... 46 2.8 BJT Action in Voltage Amplification……………………………………………………… 50 2.8.1 Terminal Current Relations………………….……………………………………...... 51 2.9 Maximum power Dissipation of a BJT………………………………………..……............ 53 2.9.1 Thermal Aspects………………………..……………………………….................... 54 2.9.2 Temperature Effects in BJTs……..…………………………….…...…………........ 56 2.10 Stability Factors, S(ICO), S(VBE) and S(β) ………………………………….…….…....... 59 2.11 Emitter-Bias Configuration……………………………………………………..…...…...... 59 CHAPTER (III) EXPERIMENTAL INVESTIGATION 3. The experimental Procedure …………………………………….……………………… 61 3.1Experimental work and Technique…………………………………………………… 62 3.1.1 Radiation sources……………………………………..………...…………………......... 63 3.1.2 Gamma Irradiation cell 220 ……………………..………………………..………........ 63 3.2 Device under Test (Transistor Type 2N3773 and Type 2N3055)…….…………............. 64 3.3 Semiconductor parameter analyzer (4155B/4156B)……………….….…………......... 65 3.4 Telequipment Curve Tracer Type CT71………………………………………………........ 66 3.5 Experimental Results…………………………………………....…………………...... 67 3.5.1Transistor irradiation by Co60 gamma…………………….…………………….……. 67 3.5.2. Transistor under temperature effect………………..……………...……..…………. 67 3.5.3. Group ( I ) NPN type 2N3055 Under Radtion Effect ………………………….. 68 3.5.4. Group (II) NPN type 2N3773 Under Radiation Effect………………..………... 73 3.6. The effect of Temperature on BJT type 2N3773…………………………………. 79 4 CHAPTER (IV) Modeling of Power Transistor with Radiation Field Effect 4.1 Gamma rays ………………………………………………………….…………………........ 84 4.2 Ionization damage………………………………………………………..…….................... 84 4.3 Power bipolar transistor model with radiation effects………………………………......... 85 4.3.1 Bipolar junction transistor …………………………………..………..…….……........ 85 4.3.2 Degradation of gain……………………………………………………….…….…....... 85 4.3.3 Bulk damage…………………………..…………………………………………. 87 4.3.4 Influence of base width……………..………………………….…….……................... 88 4.4 Radiation Inclusive Ebers-Moll Models ……………………….…..…………..…….......... 89 4.5 Model of NPN-transistor under radiation effect…………………..…..………….............. 91 4.6 Power BJT Emitter Stabilized bias Circuit………………………………………................ 94 4.7 The effect of applied circuit using BJT as a control element under radiation and temperature ……………………………………………………….……...………………….. 95 4.7.1. Series Regulation Darlington Configuration……………..………………….…...... 95 1. The Effect of Radiation ……………………………..………………….……..…...... 96 2. The Effect of Temperature ………………………..…….………...………..….......... 96 4.7.2 The applied simulated amplifier circuit by BJT …………..…………....................... 97 4.7.3The applied control power circuit bipolar junction transistor 2N3055PowerTransistorSources…………………………….…….…..…………........ 99 4.7.3.1 Ignition Coil Driver with 2N3055 Transistor and 555 IC………………….......... 99 4.7.3.2 Simulated control power circuit using BJT NPN type 2N3055 under radiation and temperature effect ………………………….….………............. 101 4.7.3.3 Transient time ……………………………………………………....……….............. 103 4.7.4 H-Bridge Motor Driver Using Bipolar Transistors………………..…….................. 104 4.7.4.1 Controlling the H-Bridge Motor Driver………………………….……………….. 106 4.7.4.2 The effect of heating over H-Bridge motor Driver using Bipolar transistors…. 106 4.7.4.3 H-Bridge Motor Driver Using Bipolar transistors under gamma radiation …... 107 5 CHAPTER (V) RESULTS AND DISCUSSIONS 5.1 Collector current and collector-emitter voltage characteristics…………….………......... 108 5.1.1 Gamma irradiation results…………………………………………………….…........ 108 5.1.1.1 The relation between collector-current IC and gamma dose Krad for type 2N3055…………………………………………..……………………………….. 109 5.1.1.2 The relation between collector-emitter voltage and gamma doses for type 2N3055……………………………………………..………………………….…….. 109 5.1.1.3 The relation between collector-current IC and gamma dose Krad for type 2N3773……………...…………………………………………………..............…….. 110 5.1.1.4 The relation between collector-emitter voltage and gamma doses for type 2N3773……………………………...…………………………………...….....…....... 110 5.1.1.5 The collector current IC and gamma dose Krad for two types 2N3055, 2N3773……………………………...…………………………...…………....…........ 111 5.1.1.6 The Voltage-Emitter and gamma dose krad for two types 2N3055, 2N3733………………………………………………………….………….……....... 111 5.1.1.7 The effect of gamma irradiation on BJT type 2N3773 at 10Mrad ….…...…….. 112 5.1.1.8. The effect of gamma irradiation on BJT type 2N3773 at 10krad ….……........ 112 5.1.1.9 The effect of gamma rays on the current gain …………………..……………. 113 5.2 Analytical parameters for BJT under radiation effect ………………………………. 114 5.3 Temperature Effects in BJT …………………………………………………………... 115 5.3.1 Collector- emitter voltage measurements under temperature effect….................... 115 5.3.2 Collector current measurements under temperature effect…………….…….…….. 116 5.3.3 Current gain B under the effect of temperature …….…………………………........ 117 5.4 Power Effects in BJTs…………………………………………………………………......... 117 5.4.1 Thermal resistance and permissible dissipated power under the effect of temperature for BJT device……………………………………..…………………… 118 5.4.2 The variation in BJT collector-Emitter voltage and current under radiation filed, and Heating effect ……………..………………………..…………….. 119 5.5 Emitter-bias configuration S (ICO)………………………………………………..……….. 120 5.6 Stability factors S (ICO) S (VBE) and S (B)……………………………………...……....... 121 5.6.1 Stability factor S (ICO) ………………………………………………………………. 121 6 5.6.2 Stability factor