  We discuss how the emission of electrons and ions during
electron-beam-induced physical vapor deposition can cause problems in micro-
and nanofabrication processes. After giving a short overview of different types
of radiation emitted from an electron-beam (e-beam) evaporator and how the
amount of radiation depends on different deposition parameters and conditions,
we highlight two phenomena in more detail: First, we discuss an unintentional
shadow evaporation beneath the undercut of a resist layer caused by the one
part of the metal vapor which got ionized by electron-impact ionization. These
ions first lead to an unintentional build-up of charges on the sample, which in
turn results in an electrostatic deflection of subsequently incoming ionized
metal atoms towards the undercut of the resist. Second, we show how low-energy
secondary electrons during the metallization process can cause cross-linking,
blisters, and bubbles in the respective resist layer used for defining micro-
and nanostructures in an e-beam lithography process. After the metal
deposition, the cross-linked resist may lead to significant problems in the
lift-off process and causes leftover residues on the device. We provide a
troubleshooting guide on how to minimize these effects, which e.g. includes the
correct alignment of the e-beam, the avoidance of contaminations in the
crucible and, most importantly, the installation of deflector electrodes within
the evaporation chamber.
