6.
012 Microelectronic Devices and Circuits Fall 2005 Lecture 11
Lecture 1 6.012 Overview
September 8, 2005
Contents:
1. The microelectronics revolution
2. Keys to the microelectronics revolution
3. Contents of 6.012
Reading assignment:
Howe and Sodini, Ch. 1
Announcement:
In Homework 1, need to use the MIT Microelectronics
WebLab. Go to <http://ilab.mit.edu> to get account.
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 12
1. The microelectronics revolution
Microelectronics in the news:
Image removed due to copyright restrictions.
"Intel's Andrew Grove," TIME, December 29, 1997.
Image removed due to copyright restrictions.
"The astonishing microchip," The Economist, March 23, 1996.
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 13
6.012: introductory subject to microelectronic devices
and circuits
Microelectronics is cornerstone of:
Computing revolution
Communications revolution
Consumer electronics revolution
Microelectronics: cornerstone of computing revolution
In last 30 years, computer performance per dollar has
improved more than a million fold!
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 14
Microelectronics: cornerstone of communications rev
olution
In last 20 years, communication bandwidth through a
single optical ber has increased by tenthousand fold.
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 15
Si digital microelectronics today
Take the cover o a microprocessor. What do you see?
Image removed due to copyright restrictions.
[Intel Pentium IV]
A thick web of interconnects, many levels deep
High density of very small transistors
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 16
Interconnects
Image removed due to copyright restrictions.
Image of IBM copper interconnect process can be found at:
http://www.azom.com/details.asp?ArticleID=750
______________________________________
Image removed due to copyright restrictions.
Image of SEM cross-section of CMOS 7S copper process can be found at:
http://www.azom.com/details.asp?ArticleID=750
______________________________________
Today, as many as 8 levels of interconnect using Cu.
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 17
Transistor size scaling
Image removed due to copyright restrictions.
2orders of magnitude reduction in transistor size in 30
years.
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 18
Evolution of transistor density
Moores Law:
doubling of transistor density every 1.5 years
4orders of magnitude improvement in 30 years.
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 19
Benets of continuous integration
Exponential improvements in:
system performance
costperfunction
powerperfunction
system reliability
Experimental SOI IBM microprocessor. Image removed due to copyright restrictions.
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 110
Clock speed
4order of magnitude improvement in 30 years
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 111
Transistor Cost
3order of magnitude reduction in 30 years
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 112
Cost per function
4order of magnitude reduction in 30 years
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 113
2. Keys to the microelectronics revolution
1. Silicon
Cheap and abundant
Amazing mechanical, chemical and electronic proper
ties
Probably, the material best known to humankind
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 114
2. MOSFET
MOSFET =
MetalOxideSemiconductor FieldEect Transistor
Good gain, isolation, and speed
MOSFET = switch
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 115
3. MOSFET scaling
MOSFET performance improves as size is decreased:
shorter switching time
lower power consumption
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 116
90 nm NMOS
Courtesy of Intel Corporation. Used with permission.
[Picture from: http://www.intel.com/technology/silicon/micron.htm]
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 117
4. CMOS
CMOS = Complementary MetalOxideSemiconductor
Complementary switch activates with V < 0
Logic without DC power consumption
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 118
NMOS and PMOS can be fabricated sidebyside in a
very compact way
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 119
5. Microfabrication technology
1 Gbit DRAM from IBM. Image removed due to copyright restrictions.
Tight integration of dissimilar devices with good iso
lation
Fabrication of extremely small structures, precisely
and reproducibly
Highvolume manufacturing of complex systems with
high yield
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 120
6. Circuit engineering
Simple device models that:
are based on physics
allow analog and digital circuit design
permit assessment of impact of device variations on
circuit performance
Circuit design techniques that:
are tolerant to logic level uctuations, noise and crosstalk
are insensitive to manufacturing variations
require little power consumption
+2.5 V
+1.0 V M2
IREF Q4
RS
M1
0V
vs + +
RL= 1 k vOUT
VBIAS +
1.0 V
M3
2.5 V
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 121
3. Contents of 6.012
Deals with microelectronic devices...
semiconductor physics
metaloxidesemiconductor eldeect transistor (MOS
FET)
bipolar junction transistor (BJT)
... and microelectronic circuits
digital circuits (mainly CMOS)
analog circuits (BJT and MOS)
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 122
One shouldnt work on semiconductors, that is a lthy
mess; who knows if they really exist!
Wolfgang Pauli, 1931
(Nobel Prize, Physics, 1945)
6.012 Microelectronic Devices and Circuits Fall 2005 Lecture 123
To the electron may it never be of any use to anybody.
favorite toast at annual dinners
at Cavendish Laboratory,
early 1900s
