Patent ID: 8288737
Filing Date: 2012-10-16
Classification: H01J

Abstract:
1. A plasma system for modifying a surface of a microscopy sample immersed in a plasma, by energetic ions extracted from the plasma in the energy range 50 eV to 1000 eV, comprising: a microscopy sample holder for holding a microscopy sample in place in a desired orientation; a receptacle holder for receiving the sample holder; and an RF antenna; the microscopy sample holder, the receptacle holder, and the RF antenna all being in electrical contact and at the same electrical potential; wherein all surfaces on the microscopy holder and the receptacle holder that are exposed to the incident energetic ions, and which have a direct line of sight to the microscopy sample, comprise a low sputter yield material, in order to minimize the amount of ion sputtered material deposited onto the microscopy sample, the microsopy holder and receptacle holder having a combined geometry that prevents any direct line of sight view from any point on the antenna or portion of the receptacle holder or sample holder that does not comprise a low sputter yield material, in order to prevent any ion sputtered material from high yield sputter surfaces exposed to the incident energetic ions from being deposited on the microscopy sample; wherein said microscopy sample is held in a perpendicular orientation relative to the RF antenna, and the portion of the sample farthest from the antenna and closest to the plasma has a very small radius of curvature, such that any electrical bias on the sample from external or self-biasing of the RF antenna causes an extremely high electrical field at the small radius of curvature.