Fabricating a circuit together
Discrete circuits require individual components to be assembled and connected, increasing complexity as circuits grow. Integration fabricates multiple components and interconnections together. A chip still requires packaging, power and external connections before it can function within a larger system.
Kilby’s early demonstration
In 1958 Jack Kilby at Texas Instruments demonstrated a microcircuit with active and passive components made from semiconductor material. It showed that the integration concept could work, while interconnections and fabrication still required improvements for practical large-scale production.
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Planar processing and monolithic design
Jean Hoerni’s planar process improved surface protection and fabrication. Robert Noyce built on it in proposing a manufacturable monolithic circuit structure. Experimental demonstration, process invention and an engineering architecture addressed related but different obstacles to practical integration.
Manufacturing and scaling
Later advances in patterning, materials processing, interconnects and circuit design increased achievable scale. Integrated circuits can implement logic, memory, analogue and other functions; the term is not synonymous with processor, and the task a chip performs depends on its design.