The Integrated Circuit

In 1958, Jack Kilby at Texas Instruments and, in 1959, Robert Noyce at Fairchild Semiconductor independently invented the integrated circuit as a solution to the problem of building electronic circuits with large numbers of components. Instead of making transistors one by one, several transistors could be made with this technique at the same time, on the same piece of semiconductor. In addition to transistors, other electric components such as resistors, capacitors, and diodes could be made by the same process with the same set of materials.  

The rudimentary IC that Kilby made contained one bipolar transistor, three resistors, and one capacitor, all made in germanium and coimected by wire bonding. For his invention of the IC, Jack Kilby was awarded the Nobel Prize in physics in 2000. The monolithic (monolith means single stone ) IC that Noyce proposed in 1959 was a flip-flop circuit containing six devices, in which the aluminum interconnection lines were obtained by etching an evaporated aluminum layer over the entire oxide surface using a lithographic technique.  

Since the invention of the IC, the pace of innovation has been scorching. The IC is now the foundation of microprocessors, memory chips, and myriad other kinds of semiconductor devices. 

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Etching. After a resist is patterned on a wafer, the exposed or unwanted substrate is removed by etching processes. Subsequentiy the resist is removed, leaving a desired pattern in a functional layer of the integrated circuit. Etching is performed to pattern a number of materials in the IC fabrication process, including blanket polysiHcon, metal layers, and oxide and nitride layers. The etch process for each material is different, and adapted to the material requirements of the substrate. 

What are the technologies of the integrated circuits that are being used within the design of the system One cannot protect something, if one doesn t know how it breaks. 

A detailed account of the steps that led to the first transistor, and the steps soon afterwards to improve and miniaturise the device, and to shift from germanium to silicon, would take too much space in this chapter, and the reader must be referred to Riordan and Hoddeson s systematic and rivetting account, though space will be found for a brief account of the subsequent birth of the integrated circuit, the vector of the information age. But before this, some remarks are in order about the crucial interplay of physics and metallurgy in the run-up to the transistor. 

The advent of the integrated circuit and its foundry has now firmly integrated materials scientists into modern electronics, their function both to optimise production processes and to resolve problems. To cite Just one example, many materials scientists have worked on the problem of clectronugraiion in the thin metallic conductors built into integrated circuits, a process which eventually leads to short circuits and circuit breakdown. At high current densities, migrating electrons in... 

One widely used temperature sensor is the integrated circuit /VD590 introduced by Analog Devices. It generates a current whose value in (J.A (microamperes) is equal to the temperature in degrees Kelvin (K). 

The study of electrons trapped in matter (commonly termed solid state ) led eventually to the invention of the transistor in 1947 by Walter Brattain, John Bardeen, and William Shockley at Bell Laboratories, and then to the integrated circuit hy Robert Noyce and Jack Kilby a decade later. Use of these devices dominated the second half of the twentieth century, most notably through computers, with a significant stininlus to development being given by military expenditures. 

Jack Kilby and Robert Noyce invent the integrated circuit. 1335... 

Copper is used in building the integrated circuits, chips, and printed circuit boards for computers. When 228 J of heat are absorbed by 125 g of copper at 22.38°C, the temperature increases to 27.12°C. What is the specific heat of copper ... 

Since the end of the 1970s, the polyimides have been introduced for the production of electronic components mainly for the passivation. But more and more they are interesting for the integrated circuits and multichip modulus fabrications. Processability and dielectric and thermomechanical properties are the most attractive features of these materials for the electronic31 and electro-optical applications.32... 

This procedure, with minor variations, is repeated dozens of times in the manufacture of a semiconductor chip. The chemical treatment can be carried out using reagents in a liquid phase, but gas-phase treatment by a process known as chemical vapor deposition (CVD) has become more important as individual features in the integrated circuit become smaller. 

According to the international technology roadmap for semiconductors, chips with a wafer diameter of450 mm and a feature size of 0.05 /xm by 2011 will serve to decrease manufacturing costs [29]. In the integrated circuit (IC) manufacture process as shown in Fig. 21 [30], dielectric stacks have been formed by the ion etching on the coating of dielectric material formed on the silicon surface (Fig. 21 (a)). 

The process of lithographic patterning determines the geometric features specified by the layout and patterning as the integrated circuit is fabricated layer by layer. A photomask, containing pattern information in... 

SACHEM Inc., located in Cleburne, Texas, is a producer of high-purity bulk chemicals for companies that have high-purity requirements in their chemical processing. As stated in Workplace Scene 1.2, one of their products is tetramethylammonium hydroxide (TMAH), which is sold to semiconductor industries. The analysis of TMAH for trace anions such as chloride, nitrate, nitrite, and carbonate is critical for SACHEM s quality control laboratory. If these ions are present on the integrated circuit boards manufactured by one of their semiconductor customers, they may cause corrosion severe enough to affect the functionality and performance of the electronic devices in which the circuit boards are used. In SACHEM s quality control laboratory, ion chromatography procedures have been developed to measure the anion concentrations in TMAH. Because the concentration levels are trace levels, a clean room environment, like that described in Workplace Scene 1.2, is used. A special procedure for carbonate analysis is required so that the absorption of carbon dioxide from the atmosphere can be minimized. 

Semiconductor based devices are the integrated circuit temperature transducers which, in a limited temperature range, may produce an easy-to-read output proportional to temperature and may also be used for thermocouple compensation. 

Silicon dioxide is also used to insulate regions of the integrated circuit. Here silicon dioxide is grown on the silicon surface by heating it to about 1000°C in the presence of oxygen. 

As the integrated circuit (IC) industry has chosen chemical mechanical planarization (CMP) as one of the indispensable processes in the generations of transistor gate lengths equal to or smaller than 0.35/im, it is imperative that the CMP-related process problems be investigated and... 

While the metal (primarily Fe, iron) contamination of W CMP does not directly lead to any functionality or yield loss in the manufacturing of products of the current 0.35- m or larger technologies, it is questionable that the Fe contamination can be acceptable for the products with device geometries 0.25 fim and smaller. As the speed of the transistor increases to a certain crossover point, the speed of the integrated circuit as a whole becomes predominately dictated by the back-end processes [21]. 

The ability to manipulate fluids in channels with dimensions of tens of micrometers and less has revolutionized biology and chemistry in the same way the invention of the integrated circuit by Kilby and Noyce in the 1950s spawned the progress... 

The pressure switch is connected to an integrator circuit. The integrator circuit is characterized by an output voltage which changes slowly. This voltage increases when the pressure switch contacts are open indicating that the flow rate is below the set point. When the flow rate is above the set point, the switch contacts are closed and integrator output decreases. 

Limitations. The number of transistors present on a chip lias doubled approximately every 18 months since the integrated circuit was first developed. The main reason for this continuing decrease in the minimum feature sizes of transistors (and consequent increase in density of transistors on the chip) has been the development of photolithography. The most important limitation for further size reduction remains the development of new photo- and utlier lilliugraphic techniques. 

Electronic modules are the industry standard for controllers employing a wide range of control strategies. Although, more recently, there has been rapid development of microprocessor-based controllers (see Sections 7.20 and 7.21) where control actions are simulated using software, hard wired systems based upon the integrated circuit (IQ and operational amplifier (op-amp) are still much in evidence. 

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