Principles of VLSI Design IC Technology CMPE 413 IC Technology
What advantages do ICs have over discrete components?
Size: Sub-micron vs. millimeter/centimeter.
Speed and Power: Smaller size of IC components yields higher speed and lower power consumption due to smaller parasitic resistances, capacitances and induc- tances. Switching between ‘0’ and ‘1’ much faster on chip than between chips. Payoff at the system level: Systems are physically smaller, e.g. cell phones. Lower power consumption ripple effect => less heat => cheaper power supplies => reduced system cost.
Integrated circuit manufacturing is versatile. Simply change the mask to change the design. However, designing the layout (changing the masks) is usually the most time consum- ing task in IC design.
1 Principles of VLSI Design IC Technology CMPE 413 IC Technology
A Sample of Integrated Circuit technologies: MOS CMOS PMOS-only NMOS-only
Bipolar Transistor-transistor logic (TTL) Integrated Injection Logic (I2L)
Gallium Arsenide (GaAs)
Silicon Germanium
BiCMOS
Superconducting technologies
2 Principles of VLSI Design IC Technology CMPE 413 Brief History
1958: First Integrated Circuit Flip-flop using two transistors Built by Jack Kilby at Texas Instruments
2004 Intel Pentium 4 microprocessor (~55 million transistors) 512 Mbit DRAM ( > 0.5 billion transistors)
53% compound annual growth rate over 45 years No other technology has grown so fast so long
Driven by miniaturization of transistors Smaller is faster, cheaper, lower in power Revolutionary effects on society
Feature Size: Smallest feature on an IC, currently the length of the transistor Current feature sizes: 130 nm/ 90 nm
3 Principles of VLSI Design IC Technology CMPE 413 Annual Sales
1018 transistors manufacture in 2003 100 million for every human on the planet Global Semiconductor Billings Semiconductor Global 200 (Billions of US$) of (Billions 150
100
50
0 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 Year
4 Principles of VLSI Design IC Technology CMPE 413 Invention of the transistor
Vaccum-tubes ruled in the first half of 20th century. Large, expensive, power-hungry, unreliable
1947: First point contact transistor John Bardeen and Walter Brattain at Bell Labs
5 Principles of VLSI Design IC Technology CMPE 413 MOS Integrated Circuits
1970’s processes usually had only nMOS transistors Inexpensive, but consume power when idle
Intel 1101 256-bit SRAM Intel 4004 4-bit µProcessor
1980’s present: CMOS processes for low idle power
6 Principles of VLSI Design IC Technology CMPE 413 Why CMOS?
Power consumption (heat) of bipolar circuits reduce level of integration.
Multiple ICs offset advantage of faster speed of bipolar since intra-chip signal propagation is much smaller than inter-chip propagation. On-chip wires suffer capacitance and resistance. However, off-chip wires suf- fer from capacitance and inductance (ringing effects).
CMOS advantages:
Low power. Fully restored logic levels. Rise and fall transition times are of the same order. Very high levels of integration. High performance.
7 Principles of VLSI Design IC Technology CMPE 413 Moore’s Law
1965: Gordan Moore plotted transistor on each chip Fits straight line on a semilog plot Transistor count doubles every 18-26 months 1,000,000,000
100,000,000 Pentium 4 Pentium III 10,000,000 Pentium II Transistors Pentium Pro Pentium Intel486 1,000,000 Intel386 80286 100,000 8086 10,000 8080 8008 4004 1,000
1970 1975 1980 1985 1990 1995 2000 Year
8 Principles of VLSI Design IC Technology CMPE 413 Corollaries
Many other factors grow exponentially (clock frequency, processor performance, ...)
10,000
1,000 4004
8008
Clock Speed (MHz) Speed Clock 8080
100 8086
80286
Intel386
10 Intel486
Pentium
Pentium Pro/II/III
1 Pentium 4
1970 1975 1980 1985 1990 1995 2000 2005 Year Cost of building a semiconductor fab is doubling every three to four years.
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