Electronics
Electronic devices have hugely influenced the development of many aspects of modern society, such as telecommunications, entertainment, education, health care, industry, and security.
The semiconductor industry is one of the largest and most profitable sectors in the global economy, with annual revenues exceeding $481 billion in 2018.
Vacuum tubes (thermionic valves) were the first active electronic components which controlled current flow by influencing the flow of individual electrons, and enabled the construction of equipment that used current amplification and rectification to give us radio, television, radar, long-distance telephony and much more.
[4] The next big technological step took several decades to appear, when the first working point-contact transistor was invented by John Bardeen and Walter Houser Brattain at Bell Labs in 1947.
[5] However, vacuum tubes continued to play a leading role in the field of microwave and high power transmission as well as television receivers until the middle of the 1980s.
However, early junction transistors were relatively bulky devices that were difficult to manufacture on a mass-production basis, which limited them to a number of specialised applications.
[25] The invention of the integrated circuit by Jack Kilby and Robert Noyce solved this problem by making all the components and the chip out of the same block (monolith) of semiconductor material.
Analog electronic computers were valuable for solving problems with continuous variables until digital processing advanced.
Similarly, an overdriven transistor amplifier can take on the characteristics of a controlled switch, having essentially two levels of output.
[28] Ternary (with three states) logic has been studied, and some prototype computers made, but have not gained any significant practical acceptance.
Heat generated by electronic circuitry must be dissipated to prevent immediate failure and improve long term reliability.
Electronic noise is defined[32] as unwanted disturbances superposed on a useful signal that tend to obscure its information content.
Most modern day electronics now use printed circuit boards made of materials such as FR4, or the cheaper (and less hard-wearing) Synthetic Resin Bonded Paper (SRBP, also known as Paxoline/Paxolin (trade marks) and FR2) – characterised by its brown colour.
Health and environmental concerns associated with electronics assembly have gained increased attention in recent years, especially for products destined to go to European markets.
[36] In the 1960s, U.S. manufacturers were unable to compete with Japanese companies such as Sony and Hitachi who could produce high-quality goods at lower prices.
[37] However, during the 1990s and subsequently, the industry shifted overwhelmingly to East Asia (a process begun with the initial movement of microchip mass-production there in the 1970s), as plentiful, cheap labor, and increasing technological sophistication, became widely available there.
[38] By that time, Taiwan had become the world's leading source of advanced semiconductors[39][38]—followed by South Korea, the United States, Japan, Singapore, and China.
[39][38] Important semiconductor industry facilities (which often are subsidiaries of a leading producer based elsewhere) also exist in Europe (notably the Netherlands), Southeast Asia, South America, and Israel.
