EE 330 Lect 13 Fall 2011

EE 330 Lect 13 Fall 2011 - EE 330 Lecture 13 Devices in...

Info iconThis preview shows pages 1–15. Sign up to view the full content.

View Full Document Right Arrow Icon
EE 330 Lecture 13 Devices in Semiconductor Processes Diodes Capacitors MOS Transistors
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Basic Devices • Standard CMOS Process – MOS Transistors • n-channel • p-channel – Capacitors –R e s i s t o r s – Diodes – BJT (in some processes) • npn • pnp – JFET (in some processes) • n-channel • p-channel • Niche Devices – Photodetectors – MESFET – Schottky Diode (not Shockley) – MEM Devices –T r i a c /SCR –… . Primary Consideration in This Course Some Consideration in This Course
Background image of page 2
Temperature Coefficients Used for indicating temperature sensitivity of resistors & capacitors 6 op. temp 1dR TCR 10 ppm C RdT     This diff eqn can easily be solved if TCR is a constant  TCR 10 T T 1 2 6 1 2 T R T R e 6 1 2 1 2 10 TCR T T 1 T R T R For a resistor: Identical Expressions for Capacitors
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Review from Last Time
Background image of page 4
http://www.oftc.usyd.edu.au/edweb/devices/semicdev/doping4.html Review from Last Time
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Review from Last Time
Background image of page 6
Review from Last Time
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
B (Boron) widely used a dopant for creating p-type regions P (Phosphorus) widely used a dopant for creating n-type regions (bulk doping, diffuses fast) As (Arsenic) widely used a dopant for creating n-type regions (Active region doping, diffuses slower) Silicon Dopants in Semiconductor Processes Review from Last Time
Background image of page 8
Diodes (pn junctions) Depletion region created that is ionized but void of carriers Review from Last Time
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
pn Junctions • As forward bias increases, depletion region thins and current starts to flow • Current grows very rapidly as forward bias increases I D V D Anode Cathode Simple Diode Model: DD V =0 I >0 I=0 V<0 V D I D Simple model often referred to as the “Ideal” diode model Review from Last Time
Background image of page 10
Rectifier Application: Simple Diode Model: V D I D Review from Last Time
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
I-V characteristics of pn junction (signal or rectifier diode) 1 e I I t d V V S D Diode Equation Improved Diode Model: I S in the 10fA to 100fA range What is V t at room temp? t kT V= q k= 1.380 6504(24) × 10 23 JK -1 q = 1.602176487(40)×10 19 C k/q=8.62× 10 5 VK -1 V t is about 26mV at room temp Diode equation due to William Schockley, inventor of BJT In 1919, William Henry Eccles coined the term diode
Background image of page 12
I-V characteristics of pn junction (signal or rectifier diode) S D I I Diode Characteristics 0 0.002 0.004 0.006 0.008 0.01 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 Vd (volts) Id (amps) 1 e I I t d V V S D Diode Equation Under reverse bias, Under forward bias, t d V V S D e I I Diode Equation or forward bias simplification is unwieldy to work with analytically Improved Diode Model: Simplification of Diode Equation: Simplification essentially identical model except for V d very close to 0 I S in the 10fA to 100fA range V t is about 26mV at room temp t kT V= q k= 1.380 6504(24) × 10 23 JK -1 q = 1.602176487(40)×10 19 C k/q=8.62× 10 5 VK -1
Background image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
I-V characteristics of pn junction (signal or rectifier diode) S D I I 1
Background image of page 14
Image of page 15
This is the end of the preview. Sign up to access the rest of the document.

This document was uploaded on 01/31/2012.

Page1 / 49

EE 330 Lect 13 Fall 2011 - EE 330 Lecture 13 Devices in...

This preview shows document pages 1 - 15. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online