The composition of the wafer is silicon. The silicon is refined from quartz sand. The wafer is purified by silicon element (99.999%). Then the pure silicon is made into silicon ingots, which become the quartz semiconductor for manufacturing integrated circuits. Material, slicing it is the wafer specifically required for chip production. The thinner the wafer, the lower the production cost, but the higher the process requirements.
Wafer coating
Wafer coating film can resist oxidation and temperature resistance, and its material is a kind of photoresist.
Wafer photolithography development, etching
The basic flow of the photolithography process. The first is to coat a layer of photoresist on the surface of the wafer (or substrate) and dry it. The dried wafer is transferred to the lithography machine. The light passes through a mask and projects the pattern on the mask onto the photoresist on the wafer surface to achieve exposure and stimulate photochemical reactions. A second baking is performed on the exposed wafer, which is the so-called post-exposure baking. Post-baking is a more complete photochemical reaction. Finally, the developer is sprayed onto the photoresist on the wafer surface to develop the exposed pattern. After development, the pattern on the mask is left on the photoresist. Glue coating, baking, and development are all done in a homogenizing developer, and exposure is done in a photolithography machine. Glue developer and lithography machine are generally operated online, and wafers are transported between units and machines by robots. The entire exposure and development system is closed, and the wafer is not directly exposed to the surrounding environment to reduce the impact of harmful components in the environment on the photoresist and photochemical reactions