There are two branches in the semiconductor industry: integrated circuits and discrete devices. Integrated circuit is a kind of micro electronic device or component. Using a certain process, the transistors, diodes, resistors, capacitors, inductors and other components and wiring required in a circuit are interconnected, made on a small piece or several small pieces of semiconductor chips or dielectric substrates, and then packaged in a shell to become a micro structure with the required circuit functions; According to their different functions and structures, integrated circuit boards can be divided into analog integrated circuit boards and digital integrated circuit boards According to the manufacturing process, it can be divided into semiconductor and thin film. According to the level of integration, it can be divided into small-scale, medium scale, large-scale and very large-scale integrated circuits.