This preview shows pages 1–4. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full DocumentThis preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: 1 Semiconductor Models and Carriers • Objective : 1. Understand the electronic properties of semiconductor materials properties of semiconductor materials. • Questions to be answered : – Why is the concept of quantization important for semiconductors? – What models do we use to represent semiconductor crystals? EE360 – Lecture 3 crystals? – What do we mean by a semiconductor’s bandgap ? – What is a carrier and what are carrier properties? Quantization • We won’t study quantum mechanics in this course, but we will use the results of quantum mechanics every day mechanics every day! • Example: The hydrogen atom Electron has quantized “orbits” and quantized energy levels EE360 – Lecture 3 Nucleus (one proton) Electron From Pierret, p. 24 2 How did we arrive at a quantum mechanical model of the atom? • Problem 1: an orbiting electron should radiate energy and spiral into the energy and spiral into the nucleus, but matter is stable • Problem 2: the emission spectra of hot gases is not continuous, but contains discrete peaks EE360 – Lecture 3 • Solution: Bohr quantized the angular momentum (and thus orbits and energies) of the electrons From Modern Physics by Thornton and Rex From Pierret The Hydrogen Atom (continued) • Quantization of angular momentum leads to • where – E H is the electron binding energy – m is the electron rest mass, 9.11 × 1031 kg – q is the magnitude of the electron charge, 1.6 × 1019 C – ε is the permittivity of free space, 8.85 × 1014 Farad/m EE360 – Lecture 3 – ħ is Planck’s constant divided by 2 π , ħ = h /2 π = 6.63 × 1023 J ⋅ sec – n is the principle quantum number (an integer), and – eV is an electronvolt, a unit of energy equal to 1.60 × 1019 joules • We will use these physical quantities throughout EE360 3 The Silicon Atom...
View
Full
Document
This note was uploaded on 04/20/2008 for the course EE 360 taught by Professor Hastings during the Spring '08 term at Kentucky.
 Spring '08
 Hastings

Click to edit the document details