B8390 - DISPOSITIVI E CIRCUITI INTEGRATI DI POTENZA LM

Learning outcomes

At the end of the course, the student will acquire advanced knowledge of semiconductor power devices, including emerging technologies based on gallium nitride (GaN) and silicon carbide (SiC). They will be able to analyze the reliability of power transistors and identify techniques to improve their robustness and performance in practical applications. Finally, they will possess basic skills in the design and simulation of simple yet fundamental integrated power circuits using GaN technology.

Course contents

Introduction to Power Electronics

• Introduction to power electronics
• Application examples
• Types of devices and their functions

Semiconductor Power Devices

• Silicon (Si) power transistors:
  • Vertical MOSFET, Super Junction MOSFET, Laterally-Diffused MOSFET
    
  • Main characteristics (breakdown voltage, on-resistance, intrinsic capacitances) and operation
  • Typical applications: discrete vs integrated
• Silicon Carbide (SiC) power transistors:
  • Advantages and disadvantages compared to Si
  • Characteristics and operation
  • Typical applications: discrete
• Gallium Nitride (GaN) power transistors:
  • Advantages and disadvantages compared to Si and SiC
  • Depletion HEMT, Cascode, Enhancement HEMT (MISHEMT vs pGaN HEMT vs Fe-gate HEMT)
  • Characteristics and operating principles
  • Typical applications: discrete vs integrated
• Gallium Nitride (GaN) Schottky diodes:
  • Operating principle
  • Characteristics and applications

Reliability of Power Devices

• Common reliability issues in semiconductor devices
• Degradation and failure mechanisms in power transistors
• Mitigation techniques and reliability improvement
• Case studies of failures and research analysis
• Laboratory activities: experiments on semiconductor power transistors

Integrated Design in GaN

• Fundamentals of power circuits
• Introduction to integrated design
• Design of power circuits with GaN devices
• Circuits and driving techniques for GaN transistors and related challenges
• Layout techniques

Laboratory: Final Project

• Design of a GaN transistor (or half-bridge) with integrated gate driver
• Simulation of the project using EDA tools for integrated circuits
• Performance analysis and optimization

Readings/Bibliography

[1] B. Jayant Baliga, "Fundamentals of Power Semiconductor Devices", Springer New York, NY, ISBN978-1-4899-7765-6.

[2] Bernhard Wicht, "Design of Power Management Integrated Circuits", Wiley-IEEE Press, ISBN: 9781119123064.

[3] M. P. Kaufmann. B. Wicht, "Monolithic Integration in E-Mode GaN Technology", Springer Cham, ISBN978-3-031-15627-4.

Teaching methods

The course will be mainly structured through classroom lectures, accounting for approximately 65% of the total hours, and practical laboratory exercises, accounting for approximately 35% of the total hours.

The lectures are aimed at introducing and exploring in depth power semiconductor devices, with particular reference to Si, SiC, and GaN technologies, reliability issues, and the principles of integrated power circuit design.

The laboratory exercises are devoted to the analysis, simulation, and design of power devices and circuits, also using EDA tools for integrated circuits. The practical activities include experiments on power semiconductor transistors and the development of a final project related to a GaN-based power device or circuit.

Safety note: In order to attend the laboratory exercises, all students must have completed the e-learning training course on health and safety in study environments, covering modules 1 and 2 [https://www.unibo.it/it/servizi-e-opportunita/salute-e-assistenza/salute-e-sicurezza/sicurezza-e-salute-nei-luoghi-di-studio-e-tirocinio].

Assessment methods

The final assessment consists of a project and an oral examination.

Depending on the assigned topic, the project consists either in the evaluation of the reliability of power devices or in the design of a circuit in integrated GaN technology. The project is aimed at assessing the ability to apply the knowledge acquired to the analysis of power devices and circuits, the evaluation of their performance, and the justification of design choices.

The oral examination consists of a series of questions aimed at verifying knowledge of the topics covered during lectures and laboratory exercises, as well as understanding of the design aspects related to the project carried out.

The assessment is graded on a scale of 30 and takes into account the technical correctness of the project, the ability to analyse and critically discuss the results, knowledge of the theoretical topics, clarity of presentation, and appropriate use of technical terminology. The examination is passed with a minimum grade of 18/30.

Any use of generative AI tools in the preparation of the project must be limited, declared, and non-substantial. The final assessment will take into account the student’s ability to critically and autonomously discuss the work carried out.

Students with specific learning disabilities (SLDs) or temporary or permanent disabilities are advised to contact the relevant University office well in advance (https://site.unibo.it/studenti-con-disabilita-e-dsa/en ). The office will propose any appropriate accommodations for the students concerned. These accommodations must in any case be submitted to the course instructor for approval at least 15 days in advance. The instructor will assess their suitability, also in relation to the learning objectives of the course.

Teaching tools

The slides used to support the lectures delivered on the blackboard will be made available on the Virtuale platform, together with any supplementary materials for laboratory exercises, technical documentation, and support files for the final project.

Office hours

See the website of Andrea Natale Tallarico