04/08/2011

A brief history of transistors

To begin, we must remember that there are essentially two types of transistors:

- Bipolar transistors consist of a thin layer of doped semiconductor of a type of two zones of opposite type (NSA, for example). The vast majority of transistors as individual components of this family presented.

- The field-effect transistors as small building, SONY VAIO VGN-FZ240E Battery where the gain is a doped semiconductor. By applying a voltage to the properties next frame exchange local semiconductor can operate on the stream. Almost all transistors complex circuits (eg microprocessors) is of this type.

History:

The invention of the transistor effect in a context that has its roots in the early days of radio and telephony. Since 1936, Bell Labs was on us to replace the electromechanical switches for telephone exchanges by static devices more reliable. On the other hand,SONY VAIO VGN-FZ130E/B Battery caused the Second World War, the rapid development of semiconductors (Ge) diodes for the detection of the radar.

The semiconductor materials

The semiconductor materials are gradually being released to radio streams. First galena and copper, selenium, and finally the germanium. These materials were polycrystalline and were used to manufacture sensors and rectifiers. The strange properties of these materials as versatile, the researchers questioned. The SONY VAIO VGN-FZ140E/B Batteryeffects appear extremely semiconductors with the development of techniques for cleaning. He must get into the act with a purity of 10-12 in order to achieve a transistor. The first modern semiconductor materials (silicon doped n-type and P) were produced by S. Ohl, JH. Scaff and HC. Theurer Bell Laboratory in spring 1940 under the direction of WH. Brattain. PN junctions were then made and the manufacturing process for single crystals has been developed for the 1947th theory of semiconductors was developed by the theoretical work of Brilloulin.SONY VAIO VGN-FZ140E Battery

The field effect transistor

The field effect transistor was invented by JE 1925-1928. Lilienfeld. A patent has been filed, but no performance was possible 60 years ago. All researchers involved in the attempts of the saga of the first transistor, such as SONY VAIO VGN-FZ280E Battery triodes component in the solid state (hence the name of the network to the control electrode) to achieve. All these attempts ended in failure. The difficulty came from the state control over the interface between the gate insulator and the semiconductor channel. This problem was effectively resolved by the end of 1959 by MM. Attala, D. and E. Kahng Labate using the thermal oxide of silicon.

I remember a field-effect transistor-ring, called "Tecnetron" (invented by CNET Tezner) in an exhibition at that time.

The bipolar transistor

The bipolar transistor was invented in two stages: The story notes that J. Bardeen and WH. Brattain invented the transistor Climax Bell Lab. This equipment has worked for the first time the 23rd December 1947. It was a device rather rude, slow and unstable. It follows directly switched germanium diodes, SONY VAIO VGN-FZ250E Battery which have long been used to detect radar signals. The story says that researchers conducting a field measurement of potential in a semiconductor with a period (probably understand the behavior of diodes spikes) when presented a better effect if the distance is measured between two points is very low ( a fraction of a mm). In fact, provides the top of the diode corresponds to a small area surrounding the doped contact region. After various manipulations to emphasize that they have come to realize the first transistor with a single crystal of germanium. His statements Sony VAIO VGN-Z21MN/Bwere separated from Gold 5 / 100 mm. Bell Labs made the discovery public in June 1948. The names of the electrodes of the bipolar transistors (base, emitter and collector) is from this moment.

It is worth mentioning that the German researcher Herbert F. Mataré been noticed in 1943 to reduce "interference" between the two points of a dual detector diode to reduce the noise of a radar wave. Hired in France after the war for Westinghouse, he developed a transistor with spikes, Acer Aspire One Battery called transistron in June 1948. This performance, regardless of the work of Bell Labs, was the work of another German Welker, Heinrich, hired by Westinghouse base. He managed to obtain single crystals of germanium in sufficient quality. This device, much more reliable than those of Bell Labs, is patented in August 1948 and in France by the mass production of Westinghouse are made.

The transistor was at the crossroads (théoriquement!) invented a little later, W. Shockley of Bell Lab also attempts since 1936 to a field effect transistor to achieve. This researcher in 1948, combines a patent for a transistor and a junction point that shows the progression of his ideas. He suggested that the principle of crossing the Sony VGP-BPS5 Batterytransistor in 1949. The first prototype was developed by Bell Laboratory in April 1950 (or July 51!) Done. On September 25, 1951 licenses were offered for sale at a price of $ 25,000. The first transistor junctions in the industry, so-called "allies" were produced by two drops of indium on both sides of a thin wafer of germanium crystal. At 600 ° C, widespread in the germanium by a change of this kind of indium. It was released as the two are very close, without touching them. A transistor of this type, known as OC71 was widely marketed by Philips, SONY VAIO VGN-FW21E Battery Mullard, national, Siemens, Valvo ... From the year 1954. The transistor as a glass tube painted black up to 2 cm (with a rounded top) and 5 mm in diameter. With silicone grease in which the transistor was kept filled by his connections. This system was slow and very sensitive to temperature. The performance of this type of transistor is directly related to the thickness of the base. Supporters of the tubes were for these objects, which were then of no interest as curiosities laugh to see! I have a book in support of electronic Elec Sup, 1953, SONY VAIO VGN-FW31M Battery does not even mention these transistors!

Technical developments that led to modern transistors and integrated circuits formed in the late 50:

- Use of silicon in 1954 by Texas Instruments provided a stability much higher temperature

- Technology-MESA (1957 Texas Instruments) and planar (Fairchild 1958), which opens the door for integrated circuits, use.

The industrial use of transistors began, and quickly expanded from the early 60s, leading to a fast pipe.

Integrated circuits

An integrated circuit consists of the union of all components of an assembly on the same silicon wafer.

The first integrated circuit at Texas Instruments, was 12th September 1958 by Jack Kilby. At the same time, Robert Noyce also directed to an integrated circuit at Fairchild. In the early 70's to the first integration of field effect transistors circuits (MOS) in. First metal-gate (PMOS gate aluminum), SONY VAIO VGN-FZ21M Battery which were slow!. This technology was later improved (change in NMOS and CMOS in the early 80s). The speed of the MOS transistors to move to the point that the bipolar transistors has increased significantly in 80 years.

The essential feature of an integrated circuit is the fineness of the design that determines the size of transistors and their connections. In addition, it is smaller, it's fast! Just because the parasitic capacitances HP Pavilion DM4 are smaller. The current size of the smallest of reasons, 65nm, in steady decline. It should be about 25 nm in 2010.

The number of transistors complex circuits exponentially since the early integrated circuits (Moore's law). The complexity of the circuit current reaches 100,000 transistors. It should continue to grow at this pace at least until about 2010.

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