Lecture 7.0 Device Physics

Electronic Devices Passive Components Resistance (real #) Conductor Resistor Battery Active Components Reactance (Imaginary #) Capacitor Inductor Diode Transistor Surge Protector

Conductors Resistance, R=  L/A Capacitance Materials C=oA/d Materials Metal Interconnects Wire Lines W, Al, Cu Vias W Gates

Metal Junctions Metal Interconnects Gates Wire Lines Vias W, Al, Cu Vias W Gates Equilibration of Ef Difference in Work Functions

Resistors On Chip Circuit Board Resistors Low resistance Silicon with dopants at a particular concentration High resistance Insulator with a specific size Gate oxide-tunneling junction Oxide Insulator between two conductors Circuit Board Resistors

Capacitance C=oA/d =C/Co =1+e e = electric susceptibility

Capacitor Allows AC signal to pass Stops DC part of signal Slow build-up of charge Timing Circuits Signal Integration Reactance Imaginary # for Resistance

Capacitors in Silicon Chips SiO2 Si3N4 On Circuit Board BaTiO3 (Pb,La)TiO3 Materials SiO2 Si3N4 BaTiO3 (Pb,La)TiO3

Dielectric Constant  opt= (V/C)2 opt= n2 n=Refractive index

Circuit Board Capacitor Ni Electrodes BaTiO3 Dielectric = 2000-3000

On Chip Capacitor (Memory Chip) An electric circuit element used to temporarily STORE a charge, consisting of TWO CONDUCTIVE plates separated and insulated from each other by a DIELECTRIC.

Void

Inductor What is it? Not used on Chip On Circuit Board Reactance Coil of wire Not used on Chip On Circuit Board Used often Reactance (imaginary # for resistance)

P-n junction One way flow of current Photo Diode Laser Diode bridge Converts AC to DC Photo Diode Laser

P-N Junction - Diode N-type P-type Ef Ef

Diodes P-n junction One way flow of current Photo Diode Laser Diode bridge Converts AC to DC Photo Diode Laser

Poisson’s Equation 2U = -/( o ) N side P side n= - e Nd P side p=+ e Na U=Φ = Potential (volt)

Poisson Eq. d2U/dx2 = -/(o)

P-N Junction (Diode) – no bias V Thickness of depletion layers Nd ln = Np lp Current to equilibrate electrons from p zone to n zone due to competition of diffusion vs drift due to contact Ф.

Diode with Applied Voltage

P-N Junction (Diode) – with forward bias V Current to equilibrated electrons from p zone to n zone.

P-N Junction (Diode) – with reverse bias V Current to equilibrated electrons from p zone to n zone.

Diode Avalanche Breakdown

Diode – equivalent circuit