Operate grinding machines to abrade semiconductor crystal ingots.
What does a Crystal Grinder do?
Operates grinding machine to abrade semiconductor crystal ingot to improve cylindrical shape of ingot and attain specified diameter: Reads work order to determine target diameter of ingot. Measures ingot diameter, using calipers or micrometer, and calculates thickness of material to be removed from ingot and length of grinding time. Positions and secures ingot in trunnions or brackets on grinding machine. Adjusts machine controls for position of grinding tool and speed of grinding. Pushes buttons to activate coolant flow, rotation of ingot, grinding tool, and timer. Measures ingot diameter after grinding and continues grinding to attain specifications for diameter. May change worn grinding tools and other parts and adjust machine, using handtools. May attach graphite pieces to ends of ingot before grinding, using epoxy, and remove graphite and epoxy from ingot after grinding, using radiant oven and solvent. May operate saw to cut sample wafer from ingot for inspection. May perform routine maintenance on grinding machine, such as adding oil and cleaning machine. May operate flat grinding machine to grind flat along length of ingot and be designated Crystal Flat Grinder.