In the early 1970's integrated circuit superseded the construction of electronic circuits assembled by the soldered inter-connected of discrete components such as transistors, diodes, resistors, etc. From this time on most electronic circuits and systems contained some circuitry in the form of monolithic integrated circuit. These so-called 'silicon chips' now form the main operating parts of all electronic systems used in computers, communications, control and instrumentation systems, etc.
The fabrication of integrated circuits were the individual components such as transistors, diodes, resistors, etc. are formed and inter-connected on a single slice of silicon employs several techniques based on photolithography, the controlled diffusion of dopants and a metallic deposition onto the oxidised silicon surface, thereafter, the completed circuit is appropriately packaged to give it environmental immunity.
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