Semiconductor industry. Technician holding a set of silicon wafers for use in making microchips. He is wearing clothing to protect the silicon wafers from contamination by skin cells and hairs. He is working in a clean room that will be kept free of dust, also to protect the silicon wafers. Careful, microscopic engineering will dope the silicon with impurities like gallium and arsenic. This creates a semiconductor material that can act like small electronic components, allowing complex circuits to be constructed in a very small area. Many such microchips will be built on each of these circular wafers seen here. These microchips are the central components of computers and other equipment.