Beam Lead Technology

Beam Lead Technology

Beam Lead Technology is the name given to the structure and method of micro-fabricating a semiconductor device structure. Its original application was to high-frequency silicon switching transistors and ultra-high-speed integrated circuits.  In the early 1960's M.P.Lepselter developed the  techniques for fabricating a structure consisting of electroforming an array of thick, self-supporting gold patterns on a thin film Ti-Pt Au base, hence the name "beams", deposited on the surface of a silicon wafer . The excess semiconductor from under the beams was removed, thereby separating the individual devices and leaving them with self-supporting beam leads, or internal chiplets, cantilevered beyond the semiconductor. The contacts served as electrical leads in addition to serving the purpose of structural support for the devices.Today this micro-machining technology is also known as MEMS.

Legacy

This technology, also known as air-bridge technology, has established itself for its unsurpassed reliability in high-frequency silicon switching transistors and ultra-high-speed integrated circuits for telecommunications and missile systems. The Beam Lead devices, produced by the hundreds of millions, became the first example of a commercial microelectromechanical structure (MEMS).

Other omnipresent uses of Beam Lead Technology are the silicide process and structure (Schottky Diodes and contacts) used in every silicon integrated circuit today; plasma etching, and precision electro-forming, etc.

[BSTJ_Beam_Lead_Technology.pdf‎]File:BSTJ Beam Lead Technology.pdf[original IEEE paper.pdf]File:Original IEEE paper-1965.PDF

                                         

                                         Air-Isolated IC 1964 IEDM talk