In electronics, a wafer (also called a slice or substrate) is a thin slice of semiconductor, such as a crystalline silicon (c-Si), used for the fabrication of integrated circuits and, in photovoltaics, to manufacture solar cells. The wafer serves as the substrate for microelectronic devices built in and upon the wafer. It undergoes many microfabrication processes, such as doping, ion implantation, etching, thin-film deposition of various materials, and photolithographic patterning. Finally, the individual microcircuits are separated by wafer dicing and packaged as an integrated circuit.
Silicon wafers are available in a variety of diameters from 25.4 mm (1 inch) to 300 mm (11.8 inches). Demand is growing for both 200mm (8 inch) silicon wafer capacity and equipment, setting the stage for possible shortages in coming months. But there are also some uncertainties, if not warning signs, in the 200mm market and the entire IC industry. Trade disputes, as well as the current coronavirus outbreak in China, likely will impact the chip and equipment markets. The size of the impact and the duration remains unclear for now.
Nonetheless, for years the 200mm (8 inch) silicon wafer has been a sizeable business for chipmakers and equipment vendors alike. 200mm (8 inch) silicon wafer are older facilities that process chips at mature nodes, which range from 350nm to 90nm. In total, there are more than 200 fabs worldwide that produce chips using 200mm (8 inch) silicon wafers. Today, China has several new 200mm silicon wafers projects on the drawing board.
Today, demand for 200mm (8 inch) silicon wafers capacity is a mixed picture. One way to quantify demand is by looking at fab utilization rates. On average, 200mm (8 inch) silicon wafer utilization rates at the foundries range from 80% to 100% today, depending on the company, according to estimates from SurplusGlobal, a supplier of secondary equipment.