Substrate grinding device and substrate grinding method

A substrate grinding method comprising:

• sucking a substrate on a rotatable work table;
• moving the work table holding the substrate so that a rotation center of the substrate is located below a cup wheel type first grinding wheel and a cup wheel type second grinding wheel and at a first grinding position within a grinding range of the first grinding wheel;
• grinding the substrate while rotating the work table, rotating the substrate held on the work table, and rotating the first grinding wheel, in a state where the rotation center of the substrate is located at the first grinding position;
• moving the work table holding the substrate so that the rotation center of the substrate is located below the first grinding wheel and the second grinding wheel and at a second grinding position within a grinding range of the second grinding wheel, after performing grinding by the first grinding wheel;
• and
• grinding the substrate while rotating the work table, rotating the substrate held on the work table, and rotating the second grinding wheel, in a state where the rotation center of the substrate is located at the second grinding position.