JPS63123049U - - Google Patents

Description

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of this invention, and FIGS. 2 to 8 are waveform diagrams showing the waveforms of various parts when the scan center position and scan width of the ion beam are optimal and inappropriate, respectively. FIG. 9 is a schematic diagram of the portion from the scanning electrode to the target in the ion implantation device, FIG. 10 is a block diagram showing an example of a conventional ion beam scanning voltage generator, and FIGS. 11 and 12 are respectively shown in FIG. FIG. 11...Scan frequency generator, 12...Scan oscillator, 13...Scan tracking circuit, 14...Scan amplifier, 18...Mask current detector, 19...
Timing comparator, 20... Synchronization determiner, 21...
...correction circuit.

Claims (1)

[Claims for Utility Model Registration] A scanning frequency generator that generates a vertical square wave signal and a horizontal square wave signal corresponding to a vertical scanning frequency and a horizontal scanning frequency, respectively; a scanning oscillator that generates a vertical triangular wave signal and a horizontal triangular wave signal, each having the same frequency and synchronization with the shape wave signal; and a triangular wave for vertical scanning from the vertical triangular wave signal, the horizontal triangular wave signal, and the accelerating voltage of the ion beam. a scan tracking circuit that generates a voltage and a DC voltage for vertical offset, a triangular wave voltage for horizontal scan, and a DC voltage for horizontal offset; a scan amplifier that amplifies the voltage and a DC voltage for horizontal offset and applies them to a pair of vertical scan electrodes and a pair of horizontal scan electrodes; a mask current detector that detects a mask current flowing through the mask; and a mask current detector that detects a mask current flowing through the mask; The rising and falling timings of each of the wave signal and the horizontal square wave signal are compared with the mask current conduction timing to determine whether the vertical square wave signal and the horizontal square wave appear outside the mask current conduction timing. a timing comparator that generates a pulse at each rising and falling timing of the signal; and synchronization of the output pulse of the timing comparator with each rising and falling timing of the vertical square wave signal and the horizontal square wave signal. a synchronization determiner that determines the presence or absence of the synchronization determination device; An ion beam scanning voltage generator comprising: a correction circuit that selectively corrects a DC voltage so as to eliminate the output pulse of the timing comparator.