SPINDLE DROP DISTANCE INFORMATION DETECTION MECHANISM AND SUBSTRATE PROCESSING APPARATUS INCORPORATING SPINDLE DROP DISTANCE INFORMATION DETECTION MECHANISM

To provide a substrate processing apparatus incorporating a spindle drop distance information detection mechanism which makes a canceling circuit unnecessary, reduces adjustment man-power of the canceling circuit, simplifies component composition of a spindle drop distance information detection mechanism, thereby, makes the substrate processing apparatus small-sized and inexpensive and detects electric current flowing through a drill simply and accurately to facilitate processing of a small-sized substrate.SOLUTION: A spindle drop distance information detection mechanism B in a substrate processing apparatus 1 makes a canceling circuit unnecessary, thereupon, directly detects only electric current flowing through a drill 5 when the drill 5 is brought into contact with a desired inner layer conductive body layer 23 by means of an annular current transformer 12 through which the drill 5 penetrates, moreover, increases the electric current flowing through the drill 5 because not only a part of high-frequency current from a high-frequency transmitter 15 but also a part of harmonic current flowing into a spindle main body 3 via floating capacity CM from an inverter I are contained in the electric current, therefore, improves detection accuracy of electric current by means of the current transformer, makes an apparatus small-sized and inexpensive and, further, even in processing for sub-board having a small area, reliably detects electric current flowing through the drill and can perform processing of the substrate accurately.SELECTED DRAWING: Figure 1 【課題】キャンセル回路を不要として、キャンセル回路の調整工数低減と、スピンドル下降距離情報検出機構の部品構成を単純化することで基板加工装置を小型、安価とし、且つドリルに流れる電流を簡易且つ正確に検出して、小型の基板の加工を容易にする。【解決手段】基板加工装置１におけるスピンドル下降距離情報検出機構Ｂは、キャンセル回路を不要とした上で、ドリル５が貫通する環状の変流器１２によって、該ドリル５が所望の内層導体層２３に接触した際にドリル５に流れる電流だけを直接検知するものであり、しかも該電流には、高周波発信器１５からの高周波電流の一部だけでなく、インバータＩから浮遊容量ＣＭを介してスピンドル本体３に流れてしまう高調波電流の一部も含まれることから、ドリル５に流れる電流を増大させるので、変流器による電流の検出精度は向上するとともに、装置を小型で安価なものとした上で、面積の小さい子基板に対する加工でも、ドリルを流れる電流を確実に検出して、正確に基板の加工をすることができる。【選択図】図１