Fig. 280 - schematics showing a wide-band video amplifier manufactured circa 1962 using the passive thin-film techniques composed of 3 transistors, 2 zener diodes, and 6 resistors. With this technique all active elements can build on a single semiconductor substrate and interconnected with passive elements on a passive substrate
Fig. 279 -Close up showing the four separate circuit layers capable of housing four isolated circuits with the equivalent of up to one hundred separate components
Fig. 281a - Modern integrated circuit plastic case drilled to show the die inside and its pin connections.
Fig. 281d - Pure Silicon. Silicon is common used for the manufacturing of FET transitors, integrated circuits and so forth. However, nowadays others alternatives have been found in compound semiconductor materials such as: Gallium Arsenide, Indium Phosphide, and Mercury Cadmium Telluride, Cadmium Sulphide and Cadmium Telluride.
Fig. 281b - the structure of a modern integrated circuit observed through a microscope using the Nomarsky interference constrat technique.
Fig. 281 - Several types of modern semiconductor devices: a) Transistor b) Transistor c) Integrated circuit
In 1952, during a conference in the USA, the Bristish scientist Geoffre y William Arnold Dummer, considering the advent of the transistor and the present status of the semicondutor technology stated it would be possible to envisage electronic equipment made in a solid block with no connecting wires. In this way, the block may consist of layers of insulating, conducting, rectifying and amplifying materials, whose electrical functions would be connected directly by cutting out areas of the various layers. Such increadible prophetic soon became a reality as two engineers, Jack Kilby and Robert Noyce, working independently credited in 1959 with the invention of the first integrated circuits. In 1958, Jack Kilby working in the microminiaturization laboratory at Texas Instruments Company had applied for his patent of the first reliable integrated circuit. His researche was based in the feasibility to fabricate resistors, capacitors and transistor from semiconductor material. While resistors could make use of the ohmic properties of bulk material, reverse-biased pn junctions formed the capacitors. In the design of this first flip flop circuit it was built simultaneously in a block of monolithic Germanium the bulk resistors, pn junction capacitors, and the Mesa transistors, using the photoetching techniques. Therefore, this type of integrate circuit had some shortcomings such as: - The performance of the individual components in the circuit could not be optimized. - The interconnection of devices made it diffficult to manufature the circuit, and finally, - Its designs were expensive and difficult to be modified. However in 1959, the aforementioned disadvantages were soon overcamed through a new process developed by Robert Noyce, manager of the research and development laboratories of the semiconductor division at Fairchild, based in the transistor planar technology. In this way just after the concept proposed by Noyce, by evaporating metal onto the surface made the interconnecting, a patent was applied for starting soon the manufacturing stage, where the resitors and transitors were made by difusion in a slab of of Silicon. Fig 279
Fig. 282 - a modern integrated circuit.

In fact in the early days of integrated circuit development, the same were first built in convetional way, using discrete components to make sure they would function properly, before rendered in integrate circuit form. In this way, every junction and a connection has its counterpart in the integrated circuit. Therefore, the integrate circuit performed in terms of building blocks, whose integrated circuitry functions were controlled by gates or a bistable latch as know as a flip-flop, or digital memomories controled by a clock pulse and in this way giving birth to an operational logic. The first integrated circuits made by Fairchild used the RTL logic or - resistor-transistor logic and were marked as a component family under the trade name "Micrologic" The mass production of integrated circuits started in 1960. At the beginning besides high price tag they still had some operational drawbacks due to the different types of coupling techniques used between the transistors stages. Fig 280 In early sixties, Pacific Semiconductor Company launched in the market the TTL logic or Transitor-Transistor Logic, as well as through the researches of the IC designer James L. Buie had devised a better coupling technique known as transistor-coupled transitor logic - TCTL. Fig. 281 Even though the great evolution in the integrated circuits manufacturing, the same still used bipolar transitors as the backbone of their circuit layout. Fig. 282 Therefore, the bipolar transistor still had a high production cost as well as it was technically too limited for the complexity of the new integrated circuit topology. Soon the MOS technology developed from the researches started with the field effect transitor - MOSFET - was used in the production of semiconductor devices with high integration capacity in such way in a small area it was possible to incorporate a higher number of gates. Fig 283

Fig. 281 c - The silicon wafer prepared from the pure Silicon. Wafer or a precise semicondutor material substrate should be carefully prepared in several stages such as: slicing from the crystal and then precisely lapped and polished to obtein a scratch free surface with tight flatness and thickness tolerances. Wafer thinning, often known as backlapping, is generally carried out at the end of the manufacture process in order to reduce wafer's thermal conductivity and to speed up signal transmission across the device. Generally this involves reducing the wafer thickness from initial 400-500 mm to between 100 to 150 mm. Nowadays due to increasingly sophisticated semiconductor devices are demanding thinner wafers around 50 mm or less.

Introduced in 1971, the miniature electronic devices, which could handle several logical processing functions as know as LSI microprocessors – large scale integration –, which led to the fantastic computer
The Intel™ microprocessor 486DX 2™ provided with the cooler.

revolution. The first microprocessors were built in Silicon chips and originally were used in calculators’ machines. In 1974 the American company “Intel™” developed the 8080™ microprocessor, which was used to manufacturer the first personal computer. Since then the company launched a family of microprocessors, among them the most important landmarks are:
Type 80286™: as known as 286™, which as manufactured and distributed in large quantities all over the world.
Type 386™: the revolutionary microprocessor was built in 32 Bits chip that could run multiple programs at the same time.
The Intel™ microprocessor 486 DX2™ provided with 168-pin grid.

Type 486™: it was the first miniature electronic device to offer a built-in mathematical coprocessor which speeded up computing as well as allowing easier installation of hardware with plug and play Bios and greater speed. In the photograph it is shown the microprocessor 486 DX2™ provided with 168 pin grid array supported by 5V CC and the cooler; it was replaced soon by the faster type 486 DX4™.
Type Pentium™: originally it was the microprocessor type 586™, launched in the market in 1993. This was big leap when compared with the predecessor type 486™ as it was designed to include speech, sound and photographic images. Initially Pentium chip arose several difficulties such as high price as well as technical handicaps; among them the overheating which was quickly solved by placing a fan over the chip. This new family of microprocessors comprises the types Pentium Pro™, II, III and the latest IV.

Fig. 283 - Table showing the evolution of semiconductor devices: from the transistor to microprocessors.