Semiconductor device fabrication

Semiconductor device fabrication is the process used to create the MOSFET (metal-oxide-silicon field-effect transistor) semiconductor devices used in the integrated circuits (ICs) that are present in everyday electrical and electronic devices. It is a multiple-step sequence of photolithographic and chemical processing steps during which electronic circuits are gradually created on a wafer made of pure semiconducting material. Silicon is almost always used, but various compound semiconductors are used for specialized applications. Semiconductor device fabrication is the process used to create the MOSFET (metal-oxide-silicon field-effect transistor) semiconductor devices used in the integrated circuits (ICs) that are present in everyday electrical and electronic devices. It is a multiple-step sequence of photolithographic and chemical processing steps during which electronic circuits are gradually created on a wafer made of pure semiconducting material. Silicon is almost always used, but various compound semiconductors are used for specialized applications. The entire manufacturing process, from start to packaged chips ready for shipment, takes six to eight weeks and is performed in highly specialized facilities referred to as foundries or fabs. In more advanced semiconductor devices, such as modern 14/10/7 nm nodes, fabrication can take up to 15 weeks (about 4 months) with 11–13 weeks (3 to 4 months) being the industry average. Production in advanced fabrication facilities is completely automated, and carried out in a hermetically sealed, nitrogen environment to improve yield (number of working microchips vs the number of microchips made in a wafer) with FOUPs and automated material handling systems taking care of the transport of wafers from machine to machine. By industry standard, each generation of the semiconductor manufacturing process, also known as 'technology node', is designated by the process’s minimum feature size. Technology nodes, also known as 'process technologies' or simply 'nodes', are typically indicated by the size in nanometers (or historically micrometers) of the process's gate length. Since 2009, however, 'node' has became a commercial name for marketing purposes that indicates new generations of process technologies, without any relation to gate length, metal pitch or gate pitch. For example, GlobalFoundries' 7 nm process is similar to Intel's 10 nm process, thus the conventional notion of a process node has become blurred. As of 2019, 14 nanometer and 10 nanometer process chips are commonly in mass production, with 7 nanometer process chips in mass production by TSMC and Samsung, although their 7 nanometer node definition is similar to Intel's 10 nanometer process. The 5 nanometer process began being produced by Samsung in 2018. As of 2019, the node with the highest transistor density is TSMC's 5 nanometer node, with a density of 171.3 million transistors per square millimeter. In 2019, Samsung and TSMC announced plans to produce 3 nanometer nodes. The first MOSFET (metal-oxide-silicon field-effect transistor) semiconductor devices were fabricated by Mohamed Atalla and Dawon Kahng at Bell Labs between 1959 and 1960. There were originally two types of MOSFET technology, PMOS (p-type MOS) and NMOS (n-type MOS). Both types were developed by Atalla and Kahng when they originally invented the MOSFET, fabricating both PMOS and NMOS devices with a 20 µm process. An improved type of MOSFET technology, CMOS, was developed by Chih-Tang Sah and Frank Wanlass at Fairchild Semiconductor in 1963. CMOS was commercialised by RCA in the late 1960s. RCA used CMOS for its 4000-series integrated circuits in 1968, starting with a 20 µm process before gradually scaling to a 10 µm process over the next several years. Semiconductor device manufacturing has since spread from Texas and California in the 1960s to the rest of the world, including Asia, Europe, and the Middle East. It is a global business today. The leading semiconductor manufacturers typically have facilities all over the world. Samsung, the world's largest manufacturer of semiconductors, has facilities in South Korea and the US. Intel, the second largest manufacturer, has facilities in Europe and Asia as well as the US. TSMC, the world's largest pure play foundry, has facilities in Taiwan, China, Singapore, and the US. Qualcomm and Broadcom are among the biggest fabless semiconductor companies, outsourcing their production to companies like TSMC. They also have facilities spread in different countries.