Study of EUV mask e-beam inspection conditions for HVM

Extreme ultraviolet (EUV) e-beam patterned mask inspection (EBPMI) has been proposed by Applied Materials as a cost-effective solution for high volume manufacturing (HVM) in mask shops and fabs. Electron beam inspection technology is currently available for wafers. A recent publication described a successful sensitivity study of EUVs mask using a technology demonstration platform. Here we present a new study using extreme e-beam conditions to show the feasibility of using EBPMI in HVM. We examine potential changes in the reflectivity at the EUV wavelength after exposure to high e-beam currents, demonstrating that reflectivity does not change due to e-beam scanning. We therefore conclude that under the conditions tested, which include typical as well as extreme conditions, there is no evidence of mask damage.