OVERVIEW

This course, delivered in the first semester of the first year of the Master’s Degree program, provides students with foundational knowledge of the physical properties of crystalline materials, including metals, insulators, and semiconductors. The syllabus covers an introduction to crystal structures, the electronic and vibrational states of solids, and their thermal properties. Special emphasis is placed on the physical properties of semiconductors, whose understanding is essential for the advanced, discipline-specific courses offered in the second semester.

AIMS AND CONTENT

LEARNING OUTCOMES

By exploiting arguments derived from statistical and quantum physics a description of the properties of solids at the microscopic level will be derived. Students will master the concepts of crystal lattice, lattice dynamics, and electronic band structure. The correlations of crystal lattice and bandstructure will be highlighted in order to describe metallic, semiconductor and insulator behavio. Particular emphasis will be placed in describing the electronic bandstructure of semiconductors. Concepts dealing with the dynamical trasport properties in semiconductor including the formation of p-n junctions will be addressed. The students will address the physical basis and working principle of crucial technological devices such as Light emitting Diodes, Lasers and Solar cells.

AIMS AND LEARNING OUTCOMES

Students will develop the ability to study the properties of solids at the microscopic level by applying concepts from classical, statistical, and quantum physics. The course will provide knowledge of key topics such as crystal lattices, lattice dynamics, and electronic band structures. Students will learn to understand the correlation between crystal lattice structure and electronic band structure in order to describe the behavior of metals, semiconductors, and insulators. Particular emphasis will be placed on the description of the electronic band structure of semiconductors. The course will address concepts related to the dynamic transport properties of semiconductors, generation-recombination processes, doping, and the formation of p-n junctions. Students will deepen their understanding of the physical principles underlying the operation of crucial technological devices such as transistors, diodes, light-emitting diodes (LEDs), and solar cells.

PREREQUISITES

Basic knowledge of calculus, general physics, and modern physics is required for successful course attendance.

TEACHING METHODS

The course consists of approximately 64 hours of lectures, during which theoretical concepts, examples, and applications will be presented. Lectures will be delivered in the classroom, or remotely if in-person teaching is not permitted. The teaching materials (slides) presented during the lectures will be made available to students via the Aulaweb platform.

SYLLABUS/CONTENT

1 CRYSTAL STRUCTURE

Elementary Crystallography, Typical Crystal Structures,  X-ray Crystallography, The Bragg law , Interatomic Forces, Classification and consequences on crystal structure

2 LATTICE DYNAMICS

Sound Waves, Lattice Vibrations of One-dimensional Crystals and generalization to Three-dimensional Crystals, Phonons , Heat Capacity from Lattice Vibrations , Energy and heat capacity of a harmonic oscillator, The density of states, Einstein and Debye heat capacity interpolation scheme

3 FREE ELECTRONS IN METALS

Metal as classical gas- Drude model, Metal as quantum gas-Drude-Sommerfeld model, The Free Electron Model, Fermi Dirac statistics and the specific heat of an electron gas, The Fermi energy, Fermi wavevector , Fermi Temperature of metallic solids, Electron density of states , electronic contribution to specific heat.

4 THE EFFECT OF THE PERIODIC LATTICE POTENTIAL—ENERGY BANDS

Nearly Free Electron Theory,  The Tight Binding Approach, Bloch Theorem, Electronic Band Structure,  Classification of Crystalline Solids into Metals, Insulators and Semiconductors,

5 DYNAMIC AND TRANSPORT PROPERTIES

Electrons and holes, Semiclassical motion, group velocity, and effective mass, Dynamics in the presence of external fields, Scattering processes and electrical conductivity in metals.

6 SEMICONDUCTORS
Classification of semiconductors and Energy band diagram.

Intrinsic semiconductors. Density-of carriers and semiconductor statistics. Fermi Level, Electron and hole concentration at equilibrium, Temperature dependence of carrier concentration.

Extrinsic Semiconductors. N-doping, P-doping, Impurity energy levels. Donor and acceptor impurities, the Carrier concentration in extrinsic semiconductor, and Fermi level of extrinsic semiconductors.  Non-degenerate semiconductor. The law of mass action. Compensation and charge neutrality.

7 Transport Properties in Semiconductors

Electrons and Holes, Drift and diffusion current. Effective Masses, Conductivity and mobility, Effect of temperature, Doping and high electric field.

8 Carrier generation (doping , thermal , optical, injection). Carrier recombination : Direct and Indirect recombination processes, Carrier life-time.  Diffusion of carriers, Carrier injection, Carrier Diffusion length. Einstein relation.  Continuity equation

9 PN Junction at equilibrium (zero applied bias). Band bending and built-in voltage. Drift and diffusion currents of Majority and minority carrier across pn junction in equilibrium. Biased PN junction(overview), diode current-voltage characteristic, LEDs (overview), Solar Cells(overview))

RECOMMENDED READING/BIBLIOGRAPHY

Teaching Materials:
Lecture materials and slides will be made available on Aulaweb/TEAMS.

Recommended Textbooks:

• J.R. Hook and H.E. Hall, Solid State Physics, John Wiley & Sons

• S.H. Simon, Oxford Solid State Basics

• S.O. Kasap, Principles of Electronic Materials and Devices, McGraw-Hill

Additional References:

• H. Ibach and H. Lüth, Solid State Physics, Springer-Verlag

TEACHERS AND EXAM BOARD

LESSONS

Class schedule

The timetable for this course is available here: Portale EasyAcademy

EXAMS

EXAM DESCRIPTION

The exam will consist of an oral interview lasting approximately 45 minutes. During the interview, topics covered in the course will be discussed, focusing on theoretical knowledge and its application to practical examples. The student may begin the exam by choosing one topic from the syllabus (accounting for about one-quarter of the exam), while the remaining time will be dedicated to exploring the other parts of the program in greater depth.

ASSESSMENT METHODS

During the oral exam, the actual achievement of the expected learning outcomes will be assessed. The level of knowledge acquired on specific topics of the syllabus will be evaluated, as well as the understanding of the role of physical mechanisms that determine the properties of solids. Additionally, the student’s critical thinking skills in addressing specific cases posed by the instructor will be examined. The quality of the presentation, correct use of specialized terminology, and the ability to engage in critical reasoning regarding the specific cases proposed by the instructor will also be assessed.

FURTHER INFORMATION

Notice to students with disabilities or specific learning disorders (SLD):
Students who require exam accomodations must first upload their certification on the University’s online portal at servizionline.unige.it under the “Students” section. The documentation will be reviewed by the University’s Inclusion Services Office for students with disabilities and SLD, as detailed on the affiliated website at:
SCIENZA E TECNOLOGIA DEI MATERIALI 11430 | Students with disabilities and/or SLD | UniGe | University of Genoa | Degree Programs UniGe

Subsequently, at least 10 days before the exam date, students must send an email to the course instructor with whom they will take the exam, copying both the School’s Inclusion Coordinator for students with disabilities and SLD (sergio.didomizio@unige.it) and the Inclusion Services Office mentioned above. The email must specify:

• the course title

• the exam date

• the student’s full name and matriculation number

• the compensatory tools and dispensatory measures requested and deemed necessary

The Inclusion Coordinator will confirm to the instructor that the student is entitled to request exam accommodations and that these accommodations must be agreed upon with the instructor. The instructor will reply confirming whether the requested accommodations can be granted.

Requests must be submitted at least 10 days before the exam date to allow the instructor sufficient time to evaluate them. In particular, if students intend to use concept maps during the exam (which must be significantly more concise than those used for study), late submissions will not allow enough time for necessary adjustments.

For further information regarding the request for services and accommodations, please refer to the document: Guidelines for the request of services, compensatory tools, dispensatory measures, and specific aids.