1. TERM PAPER
on
Integrated circuits
Submitted
to
Amity School Of Engineering
Submitted
By
Chundru Raga Sumanth
B.Tech-EEE,EEE2
Enroll:A12424611007
Under the supervision
Of
MsRashmiswarnakar
(Asst. Professor)
ASET
Amity University, Uttar Pradesh
2. ACKNOWLEDGMENT
Any work visible is not the effort of the presenter only,but there are many
others behind the camera and my report is not an exception to this.So,in process
of recognizing the effort of those behind the scene,we would like to sincerely-
thank the teachers of AMITY UNIVERSITY for sharing thier valuable views
and time in completion of this project.
Above all Iam highly grateful to Ms RashmiSwarnkar,whose continuous
motivation,guidance and suggestions backed us in completing the project most
productively.Finally,not to forget the cooperation made by our classmate in
providing any relevant data they came across.
FROM:-
Chundru Raga Sumanth
B.tech-EEE
A12424611007
3. Declaration
I, Chundru Raga Sumanthof Amity School of Engineering declare that the work
embedded in this term paper entitled Integrated Circuits . It is an authentic
record of the work carried out by the author under the supervision of Assistant
Professor Ms RashmiSwarnkar of Amity School Of Engineering, Noida. The
matter presented in this term paper is original and has not been submitted in
parts or in full for diploma or degree for this or any other institution.
Chundru Raga Sumanth
A12424611007
4. Certificate
This is to certify that Mr.Chundru Raga Sumanth student of B.Tech. in
Electrical and Electronics Engineering (2011-2015) has carried out the work
presented in the project of the Term paper entitle "INTEGRATED
CIRCUITS” as a part of First year programme of Bachelor of Technology in
2012 from Amity School of Engineering , Amity University, Noida, Uttar
Pradesh under my supervision.
MsRashmiSwarnakar
(Asst.Professor)
ASET
Amity University
Noida, U.P.
5. INDEX
Sr.no Topic
1 INTEGRATE CIRCUITS
2 HISTORY
3 EVOLUTION OF
MICROELECTRONICS
4 VACUUM-TUBE EQUIPMENT
5 SOLID-STATE DEVICES
6 PRINTED CIRCUIT BOARD
7 DIFFERENCE BETWEEN
DISCRETE AND INTEGRATED
CIRCUITS
8 RELIABILITY
9 CLASSIFICATION OF
INTEGRATED CIRCUITS
10 GENERATIONS OF INTEGRATED
CIRCUITS
11 MANFACTURING OF
INTEGRATED CIRCUITS
12 ThE 555 TIMER
13 3-D INTEGRATED CIRCUITS
6. TERM PAPER ONINTEGRATED CIRCUITS
INTEGRATED CIRCUITS:
An integrated circuit (IC) can be the equivalent of dozens, hundreds, or thousands of
separate electronic parts.
Digital ICs, such as microprocessors, can equal millions of parts. Now, digital and
mixedsignal ICs are finding more applications in analog systems
A mixed-signal printed circuit board containing both analog and digital components.
HISTORY:
The integrated circuit was introduced in 1958.
It has been called the most significant technological development of the twentieth century.
Integrated circuits have allowed electronics to expand at an amazing rate. Much of the
growth has been in the area of digital electronics.
Lately, analog ICs have received more attention, and the designation “mixed-signal” is
now applied to ICs that combine digital and analog functions.
7. JACK KILBY’S ORIGINAL INTEGRATED CIRCUITS
Kilby won the 2000 Nobel Prize in Physics for his part of the invention of the integrated
circuit.Evaluation of integrated circuit/history of integrated circuit
EVOLUTION OF MICROELECTRONICS:
The earliest electronic circuits were fairly simple. They were composed of a few tubes,
transformers, resistors,
capacitors, and wiring. As more was learned by designers, they began to increase both the
size
and complexity of circuits. Component limitations were soon identified as this technology
developed.
VACUUM-TUBE EQUIPMENT
Vacuum tubes were found to have several built-in problems. Although the tubes were
lightweight,
associated components and chassis were quite heavy. It was not uncommon for such chassis
to weigh 40 to 50 pounds. In addition, the tubes generated a lot of heat, required a warm-
up time from 1 to 2 minutes, and required hefty power supply voltages of 300 volts dc and
more.
No two tubes of the same type were exactly alike in output characteristics. Therefore,
designers were
8. required to produce circuits that could work with any tube of a particular type. This meant
that additional components were often required to tune the circuit to the output
characteristics required for the tube used. Figure 1-1 shows a typical vacuum-tube chassis.
The actual size of the transformer is approximately 4 × 4 × 3 inches. Capacitors are
approximately 1 × 3 inches. The components in the figure are very large when compare to
modern microelectronics
Typical vacuum tube circuit.
A circuit could be designed either as a
complete system or as a functional
part of a larger system. In
complex systems, such as radar, many
separate circuits were needed to
accomplish the desired tasks.
Multiple-function tubes, such as dual diodes, dual triodes, tetrodes, and others helped
considerably to
reduce the size of circuits. However, weight, heat, and power consumption continued to be
problems that plagued designers.Another major problem with vacuum-tube circuits was the
method of wiring components referred toas POINT-TO-POINT WIRING. Figure 1-2 is an
excellent example of point-to-point wiring. Not only
did this wiring look like a rat's nest, but it often caused unwanted interactions between
components. For example, it was not at all unusual to have inductive or capacitive effects
between wires. Also, point-topoint wiring posed a safety hazard when troubleshooting was
performed on energized circuits because of exposed wiring and test points. Point-to-point
wiring was usually repaired with general purpose test equipment and common hand tools.
SOLID-STATE DEVICES
The transition from vacuum tubes to solid-state devices took place rapidly. As new types of
transistors and diodes were created, they were adapted to circuits. The reductions in size,
weight, and power use were impressive. Circuits that earlier weighed as much as 50 pounds
were reduce in weight to just a few ounces by replacing bulky components with the much
lighter solid-state devices. The earliest solid-state circuits still relied on point-to-point wiring
which caused many of the disadvantages mentioned earlier. A metal chassis, similar to the
type used with tubes, was required to provide physical support for the components. The
9. solid-state chassis was still considerably smaller and lighter than the older, tube chassis. Still
greater improvements in component mounting methods were yet to come. One of the most
significant developments in circuit packaging has been the PRINTED CIRCUIT BOARD (pcb),
as shown in figure 1-3. The pcb is usually an epoxy board on which the circuit leads have
been added by the PHOTOETCHING process. This process is similar to photography in that
copper-clad boards are exposed to controlled light in the desired circuit pattern and then
etched to remove the unwanted copper. This process leaves copper strips (LANDS) that are
used to connect the components. In general, printed circuit boards eliminate both the
heavy, metal chassis and the point-to-point wiring.
Printed circuit board (pcb).
Although printed circuit boards represent a major improvement over tube technology, they
are not
without fault. For example, the number of components on each board is limited by the sizes
and shapes of components. Also, while vacuum tubes are easily removed for testing or
replacement, pcb components are soldered into place and are not as easily removed.
Normally, each pcb contains a single circuit or a subassembly of a system. All printed circuit
boards within the system are routinely interconnected through CABLING HARNESSES
(groups of wiring orribbons of wiring). You may be confronted with problems in faulty
harness connections that affect system reliability. Such problems are often caused by wiring
errors, because of the large numbers of wires in aharness, and by damage to those wires
and connectors.
10. Another mounting form that has been used to increase the number of components in a
given space isthe cord word module perpendicular to the end plates. The components are
packed very closely together, appearing to be stacked like cordwood for a fireplace. The end
plates are usually small printed circuit boards, but may beinsulators and solid wire, as shown
in the figure. Cordwood modules may or may not be
ENCAPSULATED (totally imbedded in solid material) but in either case they are difficult to
repair.
DIFFERENCE BETWEEN DISCRETE CIRCUITS AND
INTEGRATED CIRCUITS :
Discrete circuits use individual resistors, capacitors, diodes, transistors, and other devices to
achieve the circuit function. These individual or discrete parts must be interconnected. The
usual approach is to use a circuit board. This method, however, increases the cost of the
circuit. The board, assembly, soldering, and testing all make up a part of the cost.
Integrated circuits do not eliminate the needfor circuit boards, assembly, soldering, and
testing.However, with ICs the number of discreteparts can be reduced. This means that the
circuitboards can be smaller, often use less power, andIntegrated Circuits that they will cost
less to produce. It may also be possible to reduce the overall size of the equipment using
integrated circuits, which can reduce costs in the chassis and cabinet.
RELIABILITY :
Integrated circuits may lead to circuits that require fewer alignment steps at the
factory. This is especially true with digital devices.
Reliability is related indirectly to the number of parts in the equipment. As the number of
parts goes up, the reliability comes down. Integrated circuits make it possible to reduce the
number of discrete parts in a piece of equipment. Thus, electronic equipment can be made
more reliable by the use of more ICs and fewer discrete components.
11. CLASSIFICATION OF INTEGRATED CIRCUITS:
INTEGRATED CIRCUITS CAN BE CLASSIFIED INTO THREE CATEGORIES
1) ANALOG IC
2) DIGITAL IC
3) MIXED SIGNAL(both analog and on digital on one chip)
ANALOG IC’S:
Analog ICs, such as sensors, power management circuits, and operational amplifiers, work
by processing continuous signals. They perform functions like amplification, active filtering,
demodulation, and mixing. Analog ICs ease the burden on circuit designers byhaving
expertly designed analog circuits available instead of designing a difficult analog circuit from
scratch.
12. Kit to make aanalog integrated circuit.
DIGITAL IC’S:
Digital integrated circuits can contain anything from one to millions of logic gates,
flip-flops, multiplexers, and other circuits in a few square millimeters. The small size of these
circuits allows high speed, low power dissipation, and reduced manufacturing cost
compared with board-level integration. These digital ICs, typically microprocessors, DSPs,
and micro controllers, work using binary mathematics to process "one" and "zero" signals.
MIXED SIGNAL:
ICs can also combine analog and digital circuits on a single chip to create
functions such as A/D converters and D/A converters. Such circuits offer smaller size and
lower cost, but must carefully account for signal interference
13. GENERATIONS OF INTEGRATED CIRCUITS:
SMALL SCALE INTEGRATION :The first integrated circuits contained only a few
transistors. Called "small-scale integration" (SSI), digital circuits containing transistors
numbering in the tens provided a few logic gates
MEDIUM SCALE INTEGRATION :
The next step in the development of integrated circuits, taken in the late 1960s, introduced
devices which contained hundreds of transistors on each chip, called "medium-scale
integration" (MSI).
VERY LARGE SCALE INTEGRATION :
The final step in the development process, starting in the 1980s and continuing through the
present, was "very large-scale integration" (VLSI). The development started with hundreds
of thousands of transistors in the early 1980s, and continues beyond several billion
transistors as of 2009.
Manfacturing of integrated circuit
Fabrication:
Placing over 1 million transistors on a piece ofsilicon the size of a fingertip is intricate work.
The current precision is less than one micron,with one-tenth of a micron now being used. A
14. micron is only about one-hundredth the diameter of a human hair.The fabrication process is
applied to thinwafers of silicon. There are eight basic steps.Some of these steps arerepeated
many timesmaking the total number of steps one hundredor more. The entire process
usually takes from10 to 30 days. The eight basic steps are:
• Deposition (forming an insulating layerof SiO2 on the silicon wafer)
• Photolithography (light-sensitive layerexposed through a patterned photomask)
• Etching (removal of patterned areas usingplasma gas or chemicals)
• Doping (placing donor and acceptor impuritiesinto the wafer by diffusion or by using ion
implantation)
• Metallization (formation of interconnectsand connection pads by depositing metal)
• Passivation (application of a protective layer)
• Testing (probes check each circuit for proper electrical function)
• Packaging (wafers are separated into chips, the chips are mounted, bonded/ wired, and
the packages are sealed) Sand is the base material for making the wafers. It is melted,
purified and then melted again in a radio frequency (RF) furnace. Figure
13-4 shows the molten silicon in a quartz crucible. A seed crystal is lowered into the
furnace until it touches the melt. After a little of the molten silicon freezes around the seed
crystal, the seed begins to rotate and is slowly retracted from the furnace. A large, single
crystal of silicon forms as the silicon moves away from the melt and cools. Pulled crystals are
also called ingots. Ingotsn are ground to a cylindrical shape and then sliced
into thin wafers with a diamond saw. The wafers then ground flat and polished to a mirror
finish.n The polished wafers are sent on to the wafer fabrication area, or clean room where
temperature, humidity, and dust are all tightly controlled. After a thorough cleaning, the
wafers are exposed to ultra pure oxygen to form a layer of silicon dioxide (SiO2). Next, the
wafers are coated with photoresist, which is a material that hardens when exposed to light.
The exposure is
15.
16.
17. made through a photomask. Each mask has a pattern that will be transferred to the wafer.
The unhardened areas of the photoresist, caused by the opaque areas of the photomask,
wash away during the developing step. The wafer is then etched to remove the silicon
dioxide and expose the patterned areas of the substrate. The exposed areas act as windows
to allow penetration by impurity atoms. The remains of the photoresist are removed with
chemicals or plasma gas. Figure 13-5 shows the major steps in this mostly photolithographic
process. The wafer is reoxidized and the photolithographic sequence is repeated from 8 to
20 times, depending on the complexity of the IC being manufactured. Thus,
photolithography is considered the core process in IC fabrication. When the basic circuit has
finally been completed, the surface is passivatedusing a silicon nitride coating. This coating
acts as an insulator and also serves to protect the surface from damage and contamination.
The wafer size back in 1971 was about 2 inches in diameter. Now, wafers as large as
12 inches in diameter are being processed. This means that ICs are being manufactured in
everincreasing batch sizes, and that’s one of the reasons costs are decreasing. A large wafer
will yield hundreds or thousands of individual chips (Figure 13-6 on page 390). Some of the
individual chips might be defective. Figure 13-7 on page 390 shows that needle sharp probes
are used to electrically test each chip. The defective ones are marked with a dot of ink for
later disposal. The wafer is cut apart with a diamond saw and the good circuits, now called
chips, are mounted onto metal headers as shown in Figure13-8 on page 390. The chip pads
and header tabs are connected with very fine wire. Ball bonding, or more likely ultrasonic
bonding, is used to make the connections. The package is
18.
19.
20. most common and ceramic or metal packages are used for military or other critical
applications. A general overview of IC fabrication has
been presented so far and more detail about transistor, diode, resistor, and capacitor circuit
functions will now be offered. Figure 13-9 shows one way to fabricate an NPN junction
transistor. A P type substrate is shown. An N_ layer is diffused into the substrate to form the
collector of the transistor. N_ means that more than the average number of impurity atoms
enter the crystal. This is called heavy doping and it serves to lower the resistance of the
collector. An N layer is then formed over the substrateusing an epitaxial process. Epitaxy is
the controlled growth on a crystalline substrate of a crystalline layer, called an epilayer. The
epilayer exactly duplicates the properties and crystal structure of the substrate. The epilayer
is oxidized and exposed through a photomask. After developing, a P type impurity such as
boron is diffused into the windows until the substrate is reached. This electrically isolates
an entire region on the N type epilayer. This is called the isolation diffusion and allows
separate electrical functions to exist in a single layer. Refer again to Fig. 13-9. Again,
photolithography opens up a window and a P-type impurity can be diffused in to form the
base of the transistor. Later, an N-type diffusion will form the emitter. Polarity reversals by
repeated diffusions would eventually saturate the crystal so their number is usually limited
to three. Since emitters are normally heavily doped in any case, the process is designed so
that the emitter diffusion is the last one. The transistor has now been electrically isolated
and its three regions have been formed. To be useful, it must be connected. Once again,
thewafer is oxidized and photolithography is used to open up windows as shown in Figure
13-10 on page 392. These expose the connection points for the emitter, base, and the
collector.Aluminum is evaporated and then deposited onto the surface of the wafer to make
contactthrough the windows. Photolithography is used to pattern the metal layer. Etching
removes the unwanted aluminum and Fig. 13-10(c) and (d) shows what remains. Complex
ICs can have two or even three separate aluminumlayers separated by dielectric
layers.While the transistors are being formed, diodes are also being formed.
21.
22. Figure 13-12 shows how a capacitor might be formed. The N type region acts as one plate,
analuminum layer as the other, and silicon dioxide serves as the insulator. Another
approach is to use a reverse-biased P-N junction as a capacitor. Both methods are used.
Figure 13-13 illustrates resistor formation. Different values of resistance are realized by
controlling the size of the N channel and the level of doping. Once again, heavy doping
produces less resistance. An MOS transistor is shown in Figure 13-14. Notice the insulating
(SiO2) layer between the gate and the channel. MOS transistors take up less space than BJTs
and are often preferred for that reason. IC components have certain limitationswhen
compared with discrete components:
• Resistor accuracy is limited. However, resistors in hybrid ICs can be laser trimmed to
overcome this.
• Very low and very high resistor values are not practical.
• Inductors are usually not practical.
• Only small values of capacitance arepractical.
• PNP transistors tend to not perform as well as discrete types.
The 555 Timer :
The NE555 IC timer offers low cost and versatility.
23. It is available in the 8-pin mini-DIP and in the miniature molded small outline package
(MSOP).
The 555 provides stable time delays or free running oscillation. The time-delay mode is RC-
controlled by two external components.
Timing from microseconds to hours is possible. The oscillator mode requires three or more
external components, depending on the desired output waveform. Frequencies from less
than 1
Hz to
500 kHz
with
duty
cycles
from 1
to 99
percent
can be
attained
.
Advances in integrated circuits
Among the most advanced integrated circuits are the microprocessors or "cores", which
control everything fromcomputers and cellular phones to digital microwave ovens. Digital
memory chips and ASICs are examples ofother families of integrated circuits that are
important to the modern information society. While the cost ofdesigning and developing a
complex integrated circuit is quite high, when spread across typically millions ofproduction
24. units the individual IC cost is minimized. The performance of ICs is high because the small
size allows short traces which in turn allows low power logic (such as CMOS) to be used at
fast switching speeds.ICs have consistently migrated to smaller feature sizes over the years,
allowing more circuitry to be packed oneach chip. This increased capacity per unit area can
be used to decrease cost and/or increase functionality—see Moore's law which, in its
modern interpretation, states that the number of transistors in an integrated circuitdoubles
every two years. In general, as the feature size shrinks, almost everything improves—the
cost per unitand the switching power consumption go down, and the speed goes up.
However, ICs with nanometer-scaledevices are not without their problems, principal among
which is leakage current (see subthreshold leakage for adiscussion of this), although these
problems are not insurmountable and will likely be solved or at leastameliorated by the
introduction of high-k dielectrics. Since these speed and power consumption gains
areapparent to the end user, there is fierce competition among the manufacturers to use
finer geometries. This process, and the expected progress over the next few years, is well
described by the International Technology Roadmap for Semiconductors (ITRS).In current
research projects, integrated circuits are also developed for sensoric applications in medical
implants or other bioelectronicdevices.Particular sealing strategies have to be taken in such
biogenic environments to avoid corrosion or biodegradation of the exposed
semiconductormaterials.[17] As one of the few materials well established in CMOS
technology, titaniumnitride (TiN) turned out as exceptionally stable and well suited for
electrode applications in medical implants.
Three-dimensional integrated circuit
From Wikipedia, the free encyclopediaIn electronics, a three-dimensional integrated circuit
(3D IC, 3D-IC, or 3-D IC) is a chip in which two or morelayers of active electronic components
are integrated both vertically and horizontally into a single circuit. The semiconductor
industry is pursuing this promising technology in many different forms, but it is not yet
widely used;consequently, the definition is still somewhat fluid.
3D ICs vs. 3D packaging:
3D packaging saves space by stacking separate chips in a single package. This packaging,
known as System inPackage (SiP) or Chip Stack MCM, does not integrate the chips into a
single circuit. The chips in the packagecommunicate using off-chip signaling, much as if they
were mounted in separate packages on a normal circuit board. In contrast, a 3D IC is a
single chip. All components on the layers communicate using on-chip signaling, whether
vertically or horizontally. A 3D IC bears the same relation to a 3D package that a SoC bears
to a circuit board.
25. Notable 3D chips
The Teraflops Research Chip introduced in 2007 by Intel is an experimental 80-core design
with stacked memory. Due to the high demand for memory bandwidth, a traditional IO
approach would consume 10 to 25W.[1] To improveupon that, Intel designers implemented
a TSV-based memory bus. Each core is connected to one memory tile in theSRAM die with a
link that provides 12 GB/s bandwidth, resulting in a total bandwidth of 1 TB/s while
consumingonly 2.2W.In 2004, Intel presented a 3D version of the Pentium 4 CPU.[2] The
chip was manufactured with two dies using faceto-face stacking, which allowed a dense via
structure. Backside TSVs are used for IO and power supply. For the 3D floorplan, designers
manually arranged functional blocks in each die aiming for power reduction and
performanceimprovement. Splitting large and high-power blocks and careful rearrangement
allowed to limit thermal hotspots.The 3D design provides 15% performance improvement
(due to eliminated pipeline stages) and 15% power saving(due to eliminated repeaters and
reduced wiring) compared to the 2D PentiumAn academic implementation of a 3D
processor was presented in 2008 at the University of Rochester by Professor Eby Friedman
and his students. The chip runs at a 1.4 GHz and it was designed for optimized vertical
processingbetween the stacked chips which gives the 3D processor abilities that the
traditional one layered chip could notreach.[3] One challenge in manufacturing of the three-
dimensional chip was to make all of the layers work in
harmony without any obstacles that would interfere with a piece ofinformation traveling
from one layer to another. [4]In ISSCC 2012, two 3D-IC-based multi-core designs using
GlobalFoundries' 130 nm process and Tezzazon'sFaStack technology were presented and
demonstrated. 3D-MAPS,[5] a 64 custom core implementation with twologic-die stack was
demonstrated by researchers from the School of Electrical and Computer Engineering at
Georgia Institute of Technology. The second prototype was from the Department of
Electrical Engineering andComputer Science at University of Michigan called Centip3De, a
near-threshold design based on ARM Cortex-M3
Types of integrated circuit packages
27. PQFP - Plastic Quad FlatPack;PSOP - Power SmallOutlinePackage;QFN - Quad Flat
NoLeadsPackage;QSOP - Quarter SizeOutlinePackage;SBDIP - SidebrazeDualin-Line
Package;SC-70 - Small OutlineTransistor;SIP - Single-In-LinePackage;SOIC - Small Outline
ICPackage;SOJ - Small Outline JLead Package;SOT-23 - Small OutlineTransistor;SPDIP - Shrink
PlasticDual-in-Line Package;SSOP - Shrink SmallOutlinePackage;TDFN - Thin Dual Flat
NoLeads Package;
Moores law
28.
29.
30. Constructing Gates
� transistor has three terminals
A
� source (feed with 5 volts)
A
+5 volts
� base
A
� emitter, typically connected to
An
a ground wire
� the base signal is high (close to+5 volts), the source signal is grounded and the output
If
signal is low (0). If the base signal is low(close to 0 volts), the source signalstays high and
the output signal is high (1) It turns out that, because the way a transistor works, the
easiest gates to
create are the NOT, NAND, and NOR gate
