Patent ID: 8153995

Claim:
An ion implanting apparatus for irradiating a substrate held by a holder disposed in a vacuum chamber, with an ion beam to perform ion implantation, said apparatus comprising: a holder driving device which mechanically scans said holder in a Y direction which intersects the ion beam; an illuminating device which irradiates an outer circumferential portion of the substrate held by said holder, with light from a back face side of the substrate, to form a silhouette of the outer circumferential portion; a camera which takes an image of the silhouette from a front face side of the substrate; and an image processing device which processes image data supplied from said camera to detect a position of a notch disposed in the outer circumferential portion of the substrate, wherein said holder driving device includes a support table which supports said holder and which is driven only in the Y direction, and said holder driving device fixes a position of said support table in a state where said holder is positioned in a notch detecting position where the position of the notch of the substrate is detected, and wherein said illuminating device includes: a light source which is disposed outside said vacuum chamber, and which emits light; a first light guide which guides the light emitted from said light source, into said vacuum chamber; a light projecting portion which is fixed in said vacuum chamber, and which emits the light guided by said first light guide; a light receiving portion which is attached to said support table, and which receives the light emitted from said light projecting portion only in a state where said holder is positioned in the notch detecting position; a second light guide attached to the support plate which guides the light received by said light receiving portion; and a light emitting device which is attached to said support table, and which irradiates the outer circumferential portion of the substrate held by said holder, from the back face side of the substrate with the light guided by said second light guide, to form the silhouette of the outer circumferential portion.