SEMICONDUCTOR DEVICE PHYSICS AND DESIGN

2.10. TAILORING ELECTRONIC PROPERTIES 77 The density of states in a quantum well is Conduction band N(E)= ∑ i m∗ π^2 θ(E−Ei) ...

78 CHAPTER 2. ELECTRONIC LEVELS IN SEMICONDUCTORS E 2 Ec (bulk) –W/ 2 0 +W/ 2 z E 1 E 2 E 1 k 11 E = h^2 k// + E 2 2 m* Energy P ...

2.10. TAILORING ELECTRONIC PROPERTIES 79 The occupation of the light hole subband can be ignored. In many electronic devices use ...

80 CHAPTER 2. ELECTRONIC LEVELS IN SEMICONDUCTORS x Semiconductor Insulator Device channe l with free carriers E 2 E 1 – – V ...

2.11. STRAINED HETEROSTRUCTURES 81 The built in strain causes several different effects on electronic properties: i) It can lift ...

82 CHAPTER 2. ELECTRONIC LEVELS IN SEMICONDUCTORS system the separation between the HH and LH state is given byδ=− 5. 966 eV. T ...

2.11. STRAINED HETEROSTRUCTURES 83 1.5 1.0 0.5 0.0 –0.5 0.0 0.2 0.4 0.6 0.8 Ge MOLE FRACTION (x) BAND EDGE (eV) [001] 6-fold deg ...

84 CHAPTER 2. ELECTRONIC LEVELS IN SEMICONDUCTORS 2.12DEFECTSTATESINSOLIDS........................... The band theory discussed ...

2.12. LOCALIZED STATES IN SOLIDS 85 Ev Ec Valence band Perfect structure ELECTRON ENERGY D ENSITY OF STATES (a) Ev Ec Structure ...

86 CHAPTER 2. ELECTRONIC LEVELS IN SEMICONDUCTORS The key difference between electronic states in the perfect crystal and a non- ...

2.14. PROBLEMS 87 data: Si :m∗ 1 = m∗=0. 98 m 0 m∗ 2 = m∗ 3 =m∗t=0. 19 m 0 m∗hh =0. 49 m 0 m∗h =0. 16 m 0 GaAs :m∗e = m∗dos=0. ...

88 CHAPTER 2. ELECTRONIC LEVELS IN SEMICONDUCTORS EC EV ED EC ED EV EA Figure 2.40: Figure for problem 2.8. Solve the previous ...

2.14. PROBLEMS 89 Problem 2.12For long-haul optical communication, the optical transmission losses in a fiber dictate that the o ...

90 CHAPTER 2. ELECTRONIC LEVELS IN SEMICONDUCTORS Problem 2.20In ann-type Si crystal the doping changes abruptly fromND=10^15 to ...

2.15. FURTHER READING 91 Intrinsic and extrinsic carriers J.S. Blakemore,Electron.Commun., 29, 131 (1952). J.S. Blakemore,Semic ...

Chapter 3 CHARGE TRANSPORT IN MATERIALS 3.1 INTRODUCTION Electronic devices rely on transport of electrons (holes) in materials. ...

3.2. CHARGE TRANSPORT: AN OVERVIEW 93 FIXED CHARGES Ions and tightly bound electrons Important in dielectric response, polariz ...

94 CHAPTER 3. CHARGE TRANSPORT IN MATERIALS Ev Ec Valence band Perfect structure ELECTRON ENERGY DENSITY OF STATES (a) Ev Ec Str ...

3.3. TRANSPORT AND SCATTERING 95 Crystalline Solid E-field Electron TIME F ree el ectron path DISTANCE d = vt v = μE Mobil ...

96 CHAPTER 3. CHARGE TRANSPORT IN MATERIALS –k 0 +k f^0 (k) = Σ k = 0 f(k) = f(–k) Σ f(k) = 0 –k 0 +k f(k) (a) (b) -field = 0 As ...