Precision slicing of large work pieces

Disclosed is a process capable of precision slicing substrates with a dimension in the linear direction of at least 1 meter, comprising the following steps: (I) affixing the work piece to a stage; (II) providing multiple essentially parallel, essentially straight wires having a diameter in the range from about 100 m to about 600 m, and allowing the multiple wires to contact the surface of the work piece; (III) allowing the multiple wires to travel in linear directions, optionally with cutting slurry dispensed thereon; and (IV) allowing the multiple wires to move in the slicing directions relative to the work piece; wherein in step (IV), the multiple wires maintain essentially straight and essentially parallel to each other. The process can be used for slicing silica glass substrates having a diameter large than 2 meters in producing slices thereof with a high surface flatness and a low thickness variation.