Provided are a structure for particle acceleration and a charged particle beam apparatus, which enable the suppression of electric field concentration occurring near a negative electrode part. The structure for particle acceleration includes: a ceramic body 1 having a through hole 10 formed by an inner wall surface; and a negative electrode 2 and a positive electrode 3 which are arranged, respectively, on one end and the other end of the through hole 10 in the ceramic body. The inner wall surface of the ceramic body 1 is configured such that a first region 22, which is electrically connected with the negative electrode 2, and a second region 23, which is electrically connected with the positive electrode 3, are electrically connected to each other. The surface resistivity of the first region 22 is lower than the surface resistivity of the second region 23.

A processing system may include a plasma chamber operable to generate a plasma, and an extraction assembly, arranged along a side of the plasma chamber. The extraction assembly may include a screen plate, disposed immediately adjacent to the side of the plasma chamber, the screen plate having an angled portion that comprises a screen aperture, to extract an angled ion beam towards a first end of the extraction assembly.

The extraction assembly may also include an acceleration plate, disposed outside of the screen plate, the acceleration plate having a middle portion that is shaped according to an outer surface of the screen plate. As such, the acceleration plate may include an acceleration aperture, aligned with the screen aperture, and the acceleration plate may include a distal portion adjacent to the middle portion, the distal portion having a distal end that extends beyond an end of the screen plate.