Substrate processing device and rotating shaft descending distance information detection mechanism thereof

Provided are a substrate processing apparatus and a rotating shaft descending distance information detection mechanism therefor. The rotating shaft descending distance information detection mechanism directly detects a current flowing in a drill bit when the drill bit is in contact with an inner conductor layer to be reached through a converter through which the drill bit penetrates, without eliminating a circuit. In addition to a part of high-frequency current from a high-frequency oscillator, the current also comprises a part of harmonic current from an inverter and flowing to a rotating shaft body through a parasitic capacitor, so that the current flowing in the drill bit can be increased, the current detection precision of the converter can be improved, and the current detection precision of the converter can be improved. According to the present invention, the device can be made small and inexpensive, and even when a sub-substrate having a small area is processed, the current flowing through the drill ca