Deposition

Silicon integrated circuits are playing an increasingly important role in the electronics industry. The content of integrated circuits in electronic products has increased continuously over the past decade until today it can dominate the value, as well as the cost, of a computer. One of the critical factors leading to this rapid increase in the use of integrated circuits in electronics has been the development of high-density, metal-oxide-semiconductor (MOS) integrated circuits, which allow complex logic or large, dense memories to be built on a single silicon chip. Key to the fabrication of these dense MOS chips is the use of poly-crystalline silicon as a gate-electrode material. The use of polysilicon allows realization of a self-aligned structure, greatly improving the device characteristics by reducing parasitic capacitance. It also permits more complex structures to be fabricated because of its compatibility with high-temperature silicon integrated-circuit processing.