The Physics of Integrated Devices
Scientific Disciplinary Sector (SSD)
FIS/01 - EXPERIMENTAL PHYSICS
1st quadrimester (for 2nd and 3rd years of degrees in IT, for the 2nd year of degrees in applied mathematics and for the 4th and 5th years of specialised degrees) dal Oct 2, 2006 al Dec 1, 2006.
Aim of the course is to give knowledge of the physics of semiconductor devices (p-n junction, MOSFET, CMOS; BJT) and related logic gates. The student will be able to compare various logic families in terms of their physical characteristics and performances.
Useful physical concepts to recall: electric field, potential and potential energy, elementary charge, mass of atoms, electronvolt, electrical behavioiur of materials, temperature dependence of resistivity.
Brief introduction to quantum mechanics: quantization of light: black-body radiation, photoelectronic effect; quantization of matter: atomic emission and absorption spectra, Bohr atom, Stern-Gerlach experiment; wavelike behaviour of matter: De Broglie relation, uncertainty principle.
Crystal structure and electric conduction in metals and semiconductors: atomic structure and periodic table, electron gas model of metals, conduction current in metals; covalent bond in semiconductors and the concept of hole, conduction current in semiconductors; doped semiconductors; diffusion, Einstein relation, total current in semiconductors.
Band theory fundamentals: valence and conduction band, energy gap, materials classification and doped semiconductors according to band theory.
p-n junction: polarized and non polarized junction, I-V characteristics in direct and reverse polarization for Si and Ge, breakdown.
Junction diode: rectifier diodes, Zener diodes, OR/AND gates with diodes, commutation time.
Integrated circuits fabrication: diffusion, epythaxial growth, ionic implantation; steps of planar technology, photolithography.
FET transistors: enrichment and depletion MOSFET, NMOS and PMOS. MOSFET inverters; CMOS.
BJT transistors: common emitter configuration, RTL inverter; diodes, resistors and capacitors in integrated circuits.
Other semiconductor devices: CCD basic principles.
Elementary digital circuits: basic gates in MOS and bipolar technologies: NOR and NAND MOS, NOR and NAND CMOS, NAND DTL, NAND HTL, NAND TTL; OR/NOR ECL; comparison of logic families: propagation delay, power dissipation, noise margins, fan-out.