Photochemical Machining is also called metal etching, chemical etching, chemical milling, photo etching, photochemical etching and chemical machining.
Photo etching is a process used in the creation of integrated circuits, which combines photolithography with the etching process. Photolithography is used to form patterns on semiconductor substrates coated with photoresist, resulting in selective developing of the photoresist, when exposed to ultra-violet light through a photomask. The substrate is then etched, during which process the developed photoresist serves as a barrier against the etchant, resulting in only the selected area being etched.
Watch the video for a detailed visual and explanation of the photochemical machining process.