Electronic semiconductorsalso known as computer chips, microchips, or integrated circuitsare the miniature but powerful brains of high-technology equipment. Semiconductors are composed of a myriad of tiny aluminum or copper lines and electric switches, which manipulate the flow of electrical current. Semiconductor processors are responsible for many of the steps necessary in the manufacture of each semiconductor that goes into personal computers, missile guidance systems, and a host of other electronic equipment.
Semiconductor processors are the production workers who manufacture semiconductors in disks of varying sizes, generally eight to twelve inches wide. These disks, called wafers, are thin slices of silicon on which the circuitry of the microchips is layered. Each wafer is eventually cut into dozens or scores of individual chips.
Semiconductor processors make wafers by means of photolithography, a printing process for creating patterns from photographic images. Operating automated equipment, workers imprint precise microscopic patterns of the circuitry on the wafers, etch out the patterns with acids, and replace the patterns with metals that conduct electricity. Then, the wafers receive a chemical bath to make them smooth, and the imprint process begins again on a new layer with the next pattern. Wafers usually have from 8 to 20 such layers of microscopic, three-dimensional circuitry.
Semiconductors are produced in semiconductor-fabricating plants, or “fabs.” Within fabs, the manufacturing and cutting of wafers to create semiconductors takes place in “cleanrooms”production areas that must be kept free of any airborne matter, because even extremely small particles can damage a semiconductor. All semiconductor processors working in cleanroomsboth operators and techniciansmust wear special lightweight outer garments known as “bunny suits.” These garments fit over clothing to prevent lint and other particles from contaminating semiconductor-processing worksites.
Operators, who make up the majority of the workers in cleanrooms, start and monitor the sophisticated equipment that performs the various tasks during the many steps of the semiconductor production sequence. They spend a great deal of time at computer terminals, monitoring the operation of the equipment to ensure that each of the tasks in the production of the wafer is performed correctly. Operators also may transfer wafer carriers from one development station to the next; in newer fabs, the lifting of heavy wafer carriers and the constant monitoring for quality control are increasingly being automated.
Once begun, the production of semiconductor wafers is continuous. Operators work to the pace of the machinery that has largely automated the production process. Operators are responsible for keeping the automated machinery within proper operating parameters.
Technicians account for a smaller percentage of the workers in cleanrooms, but they troubleshoot production problems and make equipment adjustments and repairs. They also take the lead in assuring quality control and in maintaining equipment. To keep equipment repairs to a minimum, technicians perform diagnostic analyses and run computations. For example, technicians may determine if a flaw in a chip is due to contamination, and peculiar to that wafer, or if the flaw is inherent in the manufacturing process.