CATHODE HOLDING ASSEMBLY AND ARC CHAMBER SUPPORT ASSEMBLY WITH THE CATHODE HOLDING ASSEMBLY
A cathode holding assembly to be mounted on an arc chamber support of an ion implanter includes a cathode holding plate (3), an insulator block (4), and a shield cap (5). The cathode holding plate (3) has a protruding outer rib (3d) towards the shield cap (5) and an opening (3a) with a protruding inner rib (3c). A protrusion (4a) of the insulator block (4) passes through the opening (3a) of the cathode holding plate (3). The insulator block (4) abuts the protruding inner rib (3c) of the opening of the cathode holding plate at an edge of the insulator block (4) to precisely fit the insulator block into the opening (3a) of the cathode holding plate (3). The shield cap (5) is arranged to a side of the insulator block opposing the protrusion (4a). A gap extends between the cathode holding plate (3) and the shield cap (5), then between the cathode holding plate (3) and the insulator block (4) where it ends.