PURPOSE: To prevent the acceleration and collision of an ion toward and with a processing chamber, and eliminate the occurrence of sputter by keeping the same potential as a discharge chamber at the processing chamber for housing a substrate to be irradiated with a charged particle generated in the discharge chamber, and a processing chamber internal surface around a through-hole for allowing the passage of a charted particle from the discharge chamber.
CONSTITUTION: A division plate 15 between a discharge camber 1 for allowing the passage of plasma 8 and a processing chamber 2, is made of conductive material, and the division plate 15 is kept at the same potential as the discharge chamber 1. According to the aforesaid construction, the division plate 15 and the plasma 8 in the processing chamber 2 have approximately the same potential, and an ion contained in the plasma 8 is not accelerated toward the division plate 15 and becomes free from collision therewith. Consequently, no sputtering takes place and no impurities other than a doping element is mixed into a substrate 3.
TSUDA YOSHIYUKI
KODERA KOICHI
YASUI HIDEAKI
