Reticles are transparent masks used in photolithography, a process in semiconductor manufacturing, to define patterns on a wafer. The patterns on the reticles are transferred to the wafer through a projection process. The patterns on reticles can range from simple to complex, and they are usually made of materials such as quartz, fused silica, or glass. Reticles play a crucial role in the production of integrated circuits, as they are used to create the intricate features that make up the electronic components on a chip. The quality of the reticle is critical in determining the yield and performance of the final product.