▎ 摘　　要

NOVELTY - An electron beam system comprises a detector (100) comprising a detector surface (110) configured to detect back-scattered electrons (152) reflected off of a sample (120); an annular cap (130)disposed on the detector surface; and a protective pellicle covering the detector surface and transparent to back scattered electrons and provides a physical barrier to particles directed at the detector surface. The protective peellicle is monoatomic or graphene or its analog. The detector surface is annular, such that an electron beam passes through the center of the detector towards the sample. The pellicles include an aperture. USE - Electron beam system for fabricating a semiconductor device e.g. logic and memory devices. ADVANTAGE - The protective pellicle is transparent to back-scattered electrons and provides a physical barrier to particles directed at the detector face, thus preventing the particles from reaching the surface of the sample. The system provides a thermal conductor to dissipate heat from the particles, so that the particles are prevented from reaching a detector face of the detector, thus reducing the amount of heat generated by the particles and improving the efficiency of the electron beam system. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a method for utilizing an electron beam system. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the electron beam system. Detector surface (110) Detector (100) Sample (120) Annular cap (130) Back-scattered electrons (152)