Wire spark machining apparatus and method for producing semiconductor wafer

A wire spark machining apparatus comprising:

• one wire electrode wound at one end around a supply side bobbin and wound at an other end around a collecting side bobbin, the wire electrode being wound multiple times around a plurality of guide rollers at intervals in a direction of a rotation axis of the guide rollers to form a parallel wire part in which a plurality of wire cutters are arranged in parallel;
• discharge waveform control circuitry to control, based on a discharge waveform command, an interpolar voltage waveform or an interpolar current waveform between the wire cutters and a workpiece;
• wire running control circuitry to control running of the wire electrode based on a wire electrode running command;
• cutting stage drive control circuitry to control, based on a stage command, a cutting feed stage that changes a relative position between the parallel wire part and the workpiece;
• machining state acquisition circuitry to acquire a cutting part electrical characteristic or electrode state information as machining state information, the cutting part electrical characteristic being a measured electrical characteristic between the wire cutters and the workpiece, the electrode state information being information on a state of the wire cutters;
• and
• machining control circuitry to determine the wire electrode running command, the discharge waveform command, and the stage command based on the machining state information.