An integrated circuit is defined as:
A circuit in which all or some of the circuit elements are inseparably associated and electrically interconnected so that it is considered to be indivisible for the purposes of construction

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An early attempt at combining several components in one device (like modern ICs) was the Loewe 3NF vacuum tube from the 1920s. Unlike ICs, it was designed with the purpose of

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The cost of designingand developing a complex integrated circuit is quite high, normally in the multiple tens of millions of dollars. Therefore, it only makes economic sense to produce

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Fabrication
The semiconductors of the periodic table of the chemical elements were identified as the most likely materials for a solid-state vacuum tube.

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The possibility of copying by photographing each layer of an integrated circuit and preparing photomasksfor its production on the basis of the photographs obtained is a

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In the early days of simple integrated circuits, the technology's large scale limited each chip to only a few transistors, and the low degree of integration meant the design process was

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Integrated circuits can be classified into analog, digital and mixed signal, consisting of analog and digital signaling on the same IC.

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