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 Lepselter1, 2 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 also serving the purpose of structural support for the devices.
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 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
