Biography|Robert Noyce — The Charleston Bench Where He Drew a Circuit on Silicon

People treat the microchip as Jack Kilby's first, or as Intel's later microprocessor.

The version that could be printed and sold was drawn in this building.

On 23 January 1959, a little more than a week after Jean Hoerni showed him a working planar transistor, Noyce wrote out a way to connect many devices on one silicon wafer without hand-soldered wires.

Hoerni's planar process sealed the junctions under silicon dioxide.

Noyce's step was to evaporate aluminum lines on that oxide so the circuit itself could be lithographed.

Kilby at Texas Instruments had built a germanium circuit with flying gold wires in September 1958.

Noyce filed U.S. patent 2,981,877 on 30 July 1959 for a semiconductor device-and-lead structure.

Fairchild's Micrologic team under Jay Last put the first planar integrated circuits into silicon in 1960.

A court later treated Noyce's interconnect method as the practical manufacturing claim.

The California plaque outside 844 East Charleston Road dates the invention to 1959 and names Noyce.

The same shed that opened as a transistor shop in 1957 is the pin for this later hour.

The building is still a working commercial address.

Read the plaque before you look for a clean room.

Photo: Robert Noyce with a circuit board, 1959. Intel Free Press, CC BY-SA 2.0, via Wikimedia Commons.