Contents
1 Introduction
2 History of Transistor
2.1 Overview of Semiconductor and Transistor History
2.1.1 The invention of the first Junction Transistor
2.1.2 The invention of the First FET transistor
2.1.3 The Invention of the First Integrated Circuit
3 Types of Transistor
3.1 Abundancy
3.2 Transistor Count
4 Conclusion
References
Introduction
The changes in a computer technology rapidly increased through few decades which is heavily influenced by the introduction of CPU transistor. Nowadays beside computers everything has a CPU such as mobile phone, smart TVs, plenty of standalone electronic devices with a cheapest price. After the replacement of an older vacuum tubes technology by a transistor, the microprocessor or CPU technology grows rapidly. Since the vacuum tubes were unreliable, bulky and generated a lot of heat, too. Especially for computer technology Vacuum tubes were unpractical.
Scientist were brainstorming the idea of semiconductor technology for a long time until the invention of the transistor announced by the Bell Telephone Laboratories in 1948.
Since then many types have been designed. Transistors are very cheap, durable, and small and have a high resistance to physical shock. The vast majority of transistors now are built as parts of IC. Transistors are used in virtually all electronic devices, including radio and television receivers, computers, and space vehicles and guided missiles.
Today's computer technology is the modest achievement in human History. The reason for the radical grows in computer technology is the invention of semiconductor transistor from germanium and later from silicon. Imagine the most abundant element from the earth's soil, silicon dioxide, the silicon transistor have made today's modernization real.
In this report the history of semiconductor, the invention and improvement of semiconductor transistor throughout the last seven decades are presented. Additionally the main type of transistor and application areas will be discussed. Beside these theoretical background the main goal of this report is to present the CPU technology with respect to transistor technology.
History of Transistor
Overview of Semiconductor and Transistor History
During World War II most scientists are occupied by war related technology such as radar. When a war ended most military related laboratories disbanded and scientist returned to researches other than military efforts. Right after the war, In January 1946, Marvin Kelly put together a group of engineers and physicist at Bell Labs to create a solid state electronics. The team included Walter Brattain, John Bardeen, John Pearson, Bert Moore, and Robert Gibney headed by Bill Shockley and Stanley Morgan [1].
Right at the beginning the team made important decision and effort directing to the two simplest semiconductor silicon and germanium. Additionally Shockley independently revived the idea of a field-effect device. They started investigating the nature of surface states and how to eliminate the effects. If the context of the knowledge of technology and science at the time of discovery considered, transistor is the greatest discovery in the history of human modernization. [2]
There are few invention that contributes to the discovery of transistor at Bell Labs
- Invention of solid state rectifier in 1874 by Ferdinand Braun
- Theoretical development of quantum mechanics in 1920's played important role toward solid-state electronics. The clear understanding the difference between a metal, insulator and semiconductors are developed due to quantum mechanics
- The invention of the concept of a field effect transistor (FET) in 1926 by Lilienfeld. Lilienfeld believed applying a voltage to a poorly conducting material would change its conductivity and thereby achieve amplification.
While those team of scientist tried to invent a better solid effect rectifier and amplifier electronics to replace vacuum tube transistor is discovered for the first time. Finally by late 1947, Bardeen and Brattain managed to make the first working point-contact transistor. Figure 1 shows the first transistor: [3]
Figure. 1 shows the first transistor (reprinted from [1].)
Figure 1 shows the first complicated transistor with germanium crystal base and two leads formed on the tip of the germanium crystal. The tip a metal coat, wax and another metal coat layer on it. The inside metal was the collector and outside metal was the emitter. The wax in the middle is a layer of insulation [1].
Figure 2. Schematic diagram of the first Subheading (reprinted from [1].)
The invention of the first Junction Transistor
Shockley, great creative burst, proceeded to write down the theory of the bipolar junction transistor, by injecting minority carrier into a semiconductor. John Shive improved the first design by putting the emitter and collector on the opposite sides of the crystal to eliminate surface paths between collector and emitter. John Shive experiment verified shockley's junction transistor theory. [4]
By April 1950, a couple of years later, Brattain, Shockley, Teal, and Sparks actually succeeded in growing the first junction npn device. In fact, the device behaved essentially as predicted by Shockley's theory. Figure. 4 is a picture of this device. The big problem, of course, in making a true bipolar semiconductor device was the need for a very thin base region. As we all know, today the base has to be on the scale of micrometers.
Figure 3. The first Junction transistor (reprinted from [1].)
By 1952, a Bell Labs team had developed a means of making high purity silicon and germanium crystals. This was done by a process called zone refining that was invented by Bill Pfann.
The invention of the First FET transistor
By 1952, Ian Ross and George Dacey succeeded in making a unipolar device. This first unipolar device was a precursor to today's FET. This configuration was made using junctions as gates rather than having the metal oxide gate structure that we have today. This junction FET worked in a pinch-off mode rather than enhancement or depletion mode as in a planar insulated gate device. [5]
Discovering that the natural oxide of silicon that occurs when you put it in a high oxygen environment has a tremendously good interface between it and pure silicon. The silicon dioxide-silicon interface is sufficiently free of surface states that you can actually make an FET. In 1955, Duane Kahng joined Bell Labs at about that time, and he fabricated the first field-effect transistor using Atalla's oxidation process. But, this turned out to be a pretty poor device.
It took until the early 1970's, 15 years before planar FET's came into common use. The delay was due to the difficulties encountered controlling impurities. This was a materials problem, and for a long time people did not realize that sodium was the killer. Specifically, any sodium at the interface between silicon and silicon dioxide had devastating effects. It was not understood how to isolate the devices from the sodium. It was a major problem to understand the purification of this interface. As you know, we now have the very highest quality silicon-silicon dioxide interface. Today we have impurities that are less than one part in one billion, which is a tremendous accomplishment. [6]
The Invention of the First Integrated Circuit
In 1957, Texas Instruments developed the mesa transistor. Then came some very important events in the late 1950's. Jack Kilby of Texas Instruments developed the first IC using these mesa techniques. Kilby used discrete wire interconnection. See Fig. 4 for a picture of that device. You can see it really was a simple device by our standards today. It has one transistor, a capacitor, and resistor all together on a piece of silicon. This is the first integrated circuit, not really large scale integration. The next thing that happened was at Fairchild, where Jean Hoerni developed the planar process for transistors. In particular, the planar process offered the capability for doing thin-film metal interconnection. Bob Noyce, using this process, made an IC using vapor deposited metal connections, which became public in 1959. [7]
Figure 4. Jack Kilby's first integrated circuit (reprinted from [1].)
Types of Transistor
Transistor can be categorized based on semiconductor material used, structure, and power rating operation frequency, amplification factor, electrical polarity or application. Although one of the above basis categorizes transistor, the major types falls to junction transistor and field effect transistor (FET) categorized mainly based on the structure.
The transistor is an arrangement of semiconductor materials that share common physical boundaries. Materials most commonly used are silicon, gallium-arsenide, and germanium, into which impurities have been introduced by a process called "doping." In n -type semiconductors the impurities or dopants result in an excess of electrons, or negative charges; in p -type semiconductors the dopants lead to a deficiency of electrons and therefore an excess of positive charge carriers or "holes" [8].
- Junction Transistor
The transferred resistance or transistor is a multi-junction device that is capable of Current gain, Voltage gain, and Signal power gain Invented in 1948 by Bardeen, Brattain and Shockley. Contains three adjoining, alternately doped semiconductor regions: Emitter (E), Base (B), and Collector (C) The middle region, base, is very thin compared to the diffusion length of minority carriers Two kinds: npn and pnp.
The Bipolar junction transistor is an active device that works as a voltage controlled current source and whose basic action is control of current at one terminal by controlling voltage applied at other two terminals. Emitter is heavily doped compared to collector. So, emitter and collector are not interchangeable. The base width is small compared to the minority carrier diffusion length. If the base is much larger, then this will behave like back-to-back diodes.[9]
Figure 4. NPN and PNP Junction transistor
- FET transistor
FET transistor commonly called as unipolar transistor since it contains one type of carrier electrons or holes (unipolar). The conventional bipolar transistor has two type of current carriers of both polarities (majority and minority) and FET has only one type of current carriers, p or n (holes or electrons). The BJT is current controlled and FET is voltage controlled current between two other terminals.
Field effect transistor is a unipolar transistor, which acts as a voltage controlled current device and is a device in which current at two electrodes is controlled by the action of an electric field at another electrode. Field effect transistor is a device in which the current is controlled and transported by carriers of one polarity (majority) only and an electric field near the one terminal controls the current between other two.
Family of FET
- Junction FET (JFET):
JFET is a unipolar transistor, which acts as a voltage controlled current device and is a device in which current at two electrodes is controlled by the action of an electric field at a pn junction. In addition to the channel, a JFET contains two ohmic contacts: the source and the drain. The JFET will conduct current equally well in either direction and the source and drain leads are usually interchangeable.
JFET consists of a piece of high resistivity semiconductor material (usually Si) which constitutes a channel for the majority carrier flow and a gate. Conducting semiconductor channel between two ohmic contacts source & drain. The magnitude of this current is controlled by a voltage applied to a gate, which is a reverse biased. (Ohmic contacts means following Ohm's law current proportional to V under constant physical condition. [9]
- MOSFET:
Field effect transistor is a unipolar transistor, which acts as a voltage controlled current device and is a device in which current at two electrodes drain and source is controlled by the action of an electric field at another electrode gate having in between semiconductor and metal very a thin metal oxide layer.[9]
- CPU Transistor Technology
CPU architecture design, implementation and form have changed through time. However fundamental operation principle remain almost unchanged. CPU has the following most principal components:
- ALU(arithmetic logic unit): performs logic and arithmetic operations
- Registers: provide operands to ALU and stores the result
- Control unit: fetches instruction from memory and execute
- memory: RAM or ROM, internal or external memory
All these principal components are made from different types of transistor in order to perform their objectives.
Nowadays modern CPU are Microprocessor. A microprocessor is a single integrated circuit or IC chip that contains CPU, memory, peripheral interfaces and other components. The most interesting change in CPU and computer technology over the course of history are abundancy and the changes in transistor count.
Abundancy
The term abundancy especially in transistor technology it is impressing in two ways. Firstly transistor is made from the most abundant compound called silica (silicon dioxide) which is 59% of earth's crust and the main constituent of more than 95 percent of the known rocks. Who would imagine that the most abundant component of the earth crust is a tool to create transistor and the most interesting reason for today's modernization? Secondly when the transistor count per inch increased, transistor abundancy per IC chip made it possible to change the CPU and computer technology architecture design and implementation to grow rapidly.
Transistor Count
Transistor count is the most common tool to measure the size of IC chip. It approximately follows the most known Moore's law. According to Moore's Law, the transistor count of the integrated circuits doubles approximately every two years. The table in appendix one shows the change in microprocessor technology, which directly related to CPU technology, with respect to transistor count through history.
Conclusion
While writing this report I have learned the technological changes in transistor history. Beside the change in physical characteristics of transistor, the most important changes are toward the count of transistor. Changes in transistor technology has a direct effect on CPU technology, therefore it can be concluded that the reason for modern computer system improvement is also the change in transistor technology.
References
- William F. Brinkman, Douglas E. Haggan, and William W. Troutman, "A History of the Invention of the Transistor and Where It Will Lead Us" IEEE journal of solid-state circuit, vol. 32, NO. 12, DEC 1997.
- M. Riordan and L. Hoddeson Crystal Fire the Birth of the Information Age. New York: Norton, p. 102.
- "A History of Engineering and Science in the Bell System—Electronics Technology (1925–1975)," p. 2, F. M. Smits, Ed
- W. Shockley, M. Sparks, and G. K. Teal, "P-N junction transistors," Phys., Rev. 83, July 1, 1951, pp. 151–162.
- G. C. Dacey and I. M. Ross, "Unipolar field-effect transistor," Proc. IRE 41, Aug. 1953, pp. 970–979.
- D. Kahng and M. M. Atalla, "Silicon-silicon dioxide field induced surface device," presented at Solid State Device Research Conf., Pittsburgh, PA, June 1960.
- J. A. Hoerni, "Planar silicon diodes and transistors," IRE Trans. Electron Devices, Mar. 8, 1961, p. 178; also presented at Professional Group on Electron Devices Meeting, Washington, D.C., Oct. 1960.
- Types of Transistor
URL: http://www.infoplease.com/encyclopedia/science/transistor-types-transistors.html
Accessed date: 20 April 2015
- Transistor and FET Characteristics
URL: http://www.dauniv.ac.in/downloads/Electronic%20Devices/09EDCJFETLesson09.pdf
Accessed date: 20 April 2015
Table of Transistor Count
Processor
Transistor count
Date of intr.
Designer
Process
Area
Intel 4004
2,300
1971
Intel
10 µm
12 mm²
Intel 8008
3,500
1972
Intel
10 µm
14 mm²
MOS Technology 6502
3,510[5]
1975
MOS Technology
8 μm
21 mm²
Motorola 6800
4,100
1974
Motorola
6 μm
16 mm²
Intel 8080
4,500
1974
Intel
6 μm
20 mm²
RCA 1802
5,000
1974
RCA
5 μm
27 mm²
Intel 8085
6,500
1976
Intel
3 μm
20 mm²
Zilog Z80
8,500
1976
Zilog
4 μm
18 mm²
Motorola 6809
9,000
1978
Motorola
5 μm
21 mm²
Intel 8086
29,000
1978
Intel
3 μm
33 mm²
Intel 8088
29,000
1979
Intel
3 μm
33 mm²
WDC 65C02
11,500[6]
1981
WDC
3 µm
6 mm²
Intel 80186
55,000
1982
Intel
3 μm
60 mm²
Motorola 68000
68,000
1979
Motorola
3.5 μm
44 mm²
Intel 80286
134,000
1982
Intel
1.5 µm
49 mm²
WDC 65C816
22,000[7]
1983
WDC
9 mm²
Motorola 68020
200,000
1984
Motorola
2 μm
Intel 80386
275,000
1985
Intel
1.5 µm
104 mm²
ARM 1
25,000[8]
1985
Acorn
Novix NC4016
16,000[9]
1985[10]
Harris Corporation
3 μm[11]
ARM 2
25,000
1986
Acorn
TI Explorer's 32-bit Lisp machine chip
553,000
1987
Texas Instruments
Intel i960
250,000
1988
Intel
0.6 µm
Intel 80486
1,180,235
1989
Intel
1 µm
173 mm²
ARM 3
300,000[8]
1989
Acorn
R4000
1,350,000
1991
MIPS
1.0 µm
213 mm²
ARM 6
30,000
1991
ARM
Pentium
3,100,000
1993
Intel
0.8 µm
294 mm²
ARM 7
578,977
1994
ARM
68.51 mm²
Pentium Pro
5,500,000
1995
Intel
0.5 µm
307 mm²
AMD K5
4,300,000
1996
AMD
0.5 µm
251 mm²
Pentium II Klamath
7,500,000
1997
Intel
0.35 µm
195 mm²
Pentium II Deschutes
7,500,000
1998
Intel
0.25 µm
113 mm²
AMD K6
8,800,000
1997
AMD
0.35 µm
162 mm²
Pentium III Katmai
9,500,000
1999
Intel
0.25 µm
128 mm²
Pentium III Coppermine
21,000,000
2000
Intel
180 nm
80 mm²
Pentium II Mobile Dixon
27,400,000
1999
Intel
180 nm
180 mm²
Pentium III Tualatin
45,000,000
2001
Intel
130 nm
81 mm²
AMD K6-III
21,300,000
1999
AMD
0.25 µm
118 mm²
AMD K7
22,000,000
1999
AMD
0.25 µm
184 mm²
Pentium 4 Willamette
42,000,000
2000
Intel
180 nm
217 mm²
Pentium 4 Northwood
55,000,000
2002
Intel
130 nm
145 mm²
Pentium 4 Prescott
112,000,000
2004
Intel
90 nm
110 mm²
Pentium 4 Prescott-2M
169,000,000
2005
Intel
90 nm
143 mm²
Pentium 4 Cedar Mill
184,000,000
2006
Intel
65 nm
90 mm²
Atom
47,000,000
2008
Intel
45 nm
24 mm²
Barton
54,300,000
2003
AMD
130 nm
101 mm²
AMD K8
105,900,000
2003
AMD
130 nm
193 mm²
Itanium 2 McKinley
220,000,000
2002
Intel
180 nm
421 mm²
Cell
241,000,000
2006
Sony/IBM/Toshiba
90 nm
221 mm²
Core 2 Duo Conroe
291,000,000
2006
Intel
65 nm
143 mm²
Core 2 Duo Allendale
169,000,000
2007
Intel
65 nm
111 mm²
Itanium 2 Madison 6M
410,000,000
2003
Intel
130 nm
374 mm²
AMD K10 quad-core 2M L3
463,000,000
2007
AMD
65 nm
283 mm²
ARM Cortex-A9
26,000,000
2007
ARM
Core 2 Duo Wolfdale3M
230,000,000
2008
Intel
45 nm
83 mm²
Itanium 2 with 9 MB cache
592,000,000
2004
Intel
130 nm
432 mm²
Core 2 Duo Wolfdale
411,000,000
2007
Intel
45 nm
107 mm²
Core i7 (Quad)
731,000,000
2008
Intel
45 nm
263 mm²
AMD K10 quad-core 6M L3
758,000,000
2008
AMD
45 nm
258 mm²
POWER6
789,000,000
2007
IBM
65 nm
341 mm²
Six-core Opteron 2400
904,000,000
2009
AMD
45 nm
346 mm²
16-core SPARC T3
1,000,000,000
2010
Sun/Oracle
40 nm
377 mm²
Apple A7 (dual-core ARM64 "mobile SoC")
1,000,000,000
2013
Apple
28 nm
102 mm²
Quad-core + GPU Core i7
1,160,000,000
2011
Intel
32 nm
216 mm²
Six-core Core i7 (Gulftown)
1,170,000,000
2010
Intel
32 nm
240 mm²
8-core POWER7 32M L3
1,200,000,000
2010
IBM
45 nm
567 mm²
8-core AMD Bulldozer
1,200,000,000
2012
AMD
32 nm
315 mm²
Quad-core + GPU AMD Trinity
1,303,000,000
2012
AMD
32 nm
246 mm²
Quad-core z196[20]
1,400,000,000
2010
IBM
45 nm
512 mm²
Quad-core + GPU Core i7 Ivy Bridge
1,400,000,000
2012
Intel
22 nm
160 mm²
Quad-core + GPU Core i7 Haswell
1,400,000,000
2014
Intel
22 nm
177 mm²
Dual-core Itanium 2
1,700,000,000
2006
Intel
90 nm
596 mm²
Six-Core Core i7 Ivy Bridge E
1,860,000,000
2013
Intel
22 nm
256 mm²
Duo-core + GPU Core i7 Broadwell-U
1,900,000,000
2015
Intel
14 nm
133 mm²
Six-core Xeon 7400
1,900,000,000
2008
Intel
45 nm
503 mm²
Quad-core Itanium Tukwila
2,000,000,000
2010
Intel
65 nm
699 mm²
Apple A8 (dual-core ARM64 "mobile SoC")
2,000,000,000
2014
Apple
20 nm
89 mm²
8-core POWER7+ 80 MB L3 cache
2,100,000,000
2012
IBM
32 nm
567 mm²
Six-core Core i7/8-core Xeon E5(Sandy Bridge-E/EP)
2,270,000,000
2011
Intel
32 nm
434 mm²
8-core Xeon Nehalem-EX
2,300,000,000
2010
Intel
45 nm
684 mm²
8-core Core i7 Haswell-E
2,600,000,000
2014
Intel
22 nm
355 mm²
10-core Xeon Westmere-EX
2,600,000,000
2011
Intel
32 nm
512 mm²
Six-core zEC12
2,750,000,000
2012
IBM
32 nm
597 mm²
Apple A8X (tri-core ARM64 "mobile SoC")
3,000,000,000
2014
Apple
20 nm
8-core Itanium Poulson
3,100,000,000
2012
Intel
32 nm
544 mm²
IBM z13
3,990,000,000
2015
IBM
22 nm
678 mm²
12-core POWER8
4,200,000,000
2013
IBM
22 nm
650 mm²
15-core Xeon Ivy Bridge-EX
4,310,000,000
2014
Intel
22 nm
541 mm²
62-core Xeon Phi
5,000,000,000
2012
Intel
22 nm
Xbox One main SoC
5,000,000,000
2013
Microsoft/AMD
28 nm
363 mm²
18-core Xeon Haswell-E5
5,560,000,000
2014
Intel
22 nm
661 mm²
SPARC M7
>10,000,000,000
2014
Oracle
20 nm
IBM z13 Storage Controller
7,100,000,000
2015
IBM
22 nm
678 mm²