This course describes how to design the structure of bipolar transistor, which has good current drivability, by explanation of each layer for electron devices properties at first. Then, figures of merit for high speed application are described with modeling for circuits. In last part, compound semiconductor which has superior property as electron devices are discussed. After explanation of physical property, transistors which are used in cell-phones, such as HEMT and HBT are described. Finally compound semiconductor power devices and III-V MOSFETs are described as prospective devices.
Target of this lecture is learning of numerical evaluation of physical phenomena in electron devices by using bipolar devices which has longest history as transistors with matured techniques. As lectures at graduate school, exhaustive learning of device's knowledge (as level of authority of the field) is aimed. In compound semiconductor, similar method is applied.
Comprehension of methods for high speed in bipolar transistors is aimed at first, and knowledge of electric properties and application of compound semiconductor are followed.
Treated subjects are:
Density of states, diffusion, drift, transport equation, recombination, band diagram, hole current in emitter layer, drift transistor, bandgap shrinkage by doping, SiGe HBT, Early effect, breakdown voltage, saturation velocity, Kirk effect, analysis of delay time, cutoff frequency, maximum oscillation frequency, large signal model. compound semiconductor, heterojunction, hot electron, inter-valley scattering, heterojunction bipolar transistors, compound semiconductor field effect transistors, power devices with wide bandgap semiconductors, III-V MOSFET, etc.,
Bipolar transistors, compound semiconductor, device physics, equivalent circuit of electron devices
|✔ Specialist skills||Intercultural skills||Communication skills||Critical thinking skills||✔ Practical and/or problem-solving skills|
Because the amount of knowledge is huge, each lecture ask simple calculation as homework. Moreover, three numerical practices are given.
Any textbook or notebook can be used as reference in final examination (description of comprehension).
|Course schedule||Required learning|
|Class 1||Basic properties of bipolar transistors||Calculate collector current and base current at provided structures|
|Class 2||Gummel plot with various effects||Draw Gummel plot with various effect|
|Class 3||Modulation of doping and composition in base||Calculate collector current with modulation of composition of base|
|Class 4||Early effect and breakdown voltage||Calculate maximum current and breakdown voltage at provided structures|
|Class 5||Practice||Numerical practice of classes 1-4|
|Class 6||Small equivalent circuits||Calculation of fT and fmax at provided structures|
|Class 7||Impact of collector design on dynamic characteristics and measurement method||Microwave properties at provided structures|
|Class 8||Modeling of large signal equivalent circuits||Draw I-V characteristics by Gummel-poon model|
|Class 9||Large signal circuit||Calculate speed in ECL circuit|
|Class 10||Practice||Numerical practice of classes 6-9|
|Class 11||Compound semiconductor and MESFET||Calculate characteristics of MESFET at provided structures|
|Class 12||Heterojunction and III-V HBT||Calculate characteristics of HBT at provided structures|
|Class 13||HEMT||Calculate characteristics of HEMT at provided structures|
|Class 14||Power devices with wide bandgap semiconductors and III-V MOSFET||Calculate characteristics of III-V MOSFET at provided structures|
To enhance effective learning, students are encouraged to spend approximately 100 minutes preparing for class and another 100 minutes reviewing class content afterwards (including assignments) for each class.
They should do so by referring to textbooks and other course material.
Distributed OCW-i . Reference of classes 1-10 is "Fundamentals of Modern VLSI Devices. 2nd Edition" by Taur and Ning.
Evaluate by comprehension of methods for high speed in bipolar transistors and knowledge of electric properties and application of compound semiconductor.
Each homework (12 times 40%), Two practice (20%) and final examination (40%)
Knowledge of electron devices I (D351), semiconductor physics(D211) and analog electronic circuits (C211) are required.