The stencil reticle is one of masks for EPL (Electron beam Projection Lithography). The ability to repair pattern defects in such masks is an essential requirement for their use. For clear defects, repair issues include deposition on the stencil pattern, electron scattering properties of the deposition material, stability of the repair against 100 kV electron beam (EB) bombardment and etching and pattern profile accuracy. For opaque defects, ion milling of the stencil material to high accuracy is required. In this paper, we discuss the repair deposition of clear defects up to 0.15 micrometer using a carbon-compound precursor and the critical dimension (CD) controllability of the exposed resist pattern with various thickness of repair depositions using Nikon's EB experimental projection column (100 kV). In addition, using a Monte Carlo simulation of the electron scattering in the silicon membrane and the repair deposition, the beam contrast is estimated for EPL at contrast aperture (CAP) size. The resist CD can be controlled using more than 2 micrometer-thick Diamond like Carbon (DLC) deposited on the stencil reticle and shaped by focused ion beam (FIB). Profiles, pattern sizes and the electron scattering properties of DLC repairs are stable against 100 kV EB irradiation (about 2 C/cm2 dosage; corresponding to half-year dosage). These results show the possibility of DLC as the repair material for clear defects. The possibility of repairing opaque defect, which involves FIB milling of sizes from 0.2 to 0.4 micrometer, is also demonstrated.