Patent 3,025,589 Filed May 1, 1959. As the two metals fuse together indium atoms with 3 valence electrons mix with the pure germanium atoms with 4 valence electrons creating P type material where the Indium atoms will appear to be short of one electron, and so will bond with only three instead of four neighbouring atoms.
The first layer in a planar transistor is a base of semiconductor material. The Web This site. Patent No. Fig 3.
Significant issues in the 1960s included "purple plague" on gold bonding wires, electromigration of aluminum interconnect lines, and MOS transistor stability. Field Effect Transistors 5.
Hoerni, J. Login username password forgot password?
Did You Know? The last US troops left Beirut. This book is provided for general reference. The second, third and fourth layers are all made flush with the top of the transistor. The three essential parts of a transistor are all there: Moore, G.
The mauve region is the base, the inner green ring the emitter, and the surrounding green sea the collector. See also Hoerni's U.
Next he diffused the emitter into the base. Fusing is stopped just before the two P type regions meet. The base was composed of negatively doped silicon, the collector and emitter of positively doped silicon; the first planar device was thus a pnp transistor.
Fairchild introduced the 2N1613 planar transistor commercially in April 1960 and licensed rights to the process across the industry. A Photographic History of the Integrated Circuit. The central cream-colored plug and the teardrop-shaped ring are aluminum connectors shown here without attached wires.
The planar transistor was invented by Jean Hoerni in 1959.
A second layer of semiconductor, with fewer impurities, is then put on top of the base. After the second layer is in place, the center of it is etched out, leaving thick edges of the second material around the sides and a thin layer above the base, in the shape of a square bowl. And they permitted fabrication of all the components of an integrated circuit from one side of a wafer 1960 Milestone.