Advanced Implant System For Vlsi Fabrication

42 SCIENCE & TECHNOLOGY Advanced implant system for VLSI fabrication In the last two decades, integrated circuit technology has invaded most areas of business, consumer products and manufac- turing. Its growth has indeed been phe- nomenal and almost exponential with the element density: nearly quadrupling every two years. This has been the result of sev- eral revolutions in the development of semiconductor devices. These have moved on from transistor-transistor logic (TrL), to emitter-coupled logic (EcL), to negative metal-oxide semiconductors (NMos), and in the last few years to complementary metal-oxide semiconductors (cMos), in which very large scale integrated (vLs0 chips of one-quarter or one-half million elements are not uncommon. by Bill Pressdee, BSc, CEng, MIEE one in which a product lot of wafers - loaded into a slotted quartz wafer carrier and introduced into an open-end high tem- perature furnace tube - is subjected to a flow of dopant transported along the tube by a...