B20-CoSi is a newly discovered Weyl semimetal that crystallizes
into a noncentrosymmetric crystal structure. However, the investigation
of B20-CoSi has so far been focused on bulk materials, whereas the
growth of thin films on technology-relevant substrates is a prerequisite
for most practical applications. In this study, we have used millisecond-range
flash-lamp annealing, a nonequilibrium solid-state reaction, to grow
B20-CoSi thin films. By optimizing the annealing parameters, we were
able to obtain thin films with a pure B20-CoSi phase. The magnetic
and transport measurements indicate the appearance of the charge density
wave and chiral anomaly. Our work presents a promising method for
preparing thin films of most binary B20 transition-metal silicides,
which are candidates for topological Weyl semimetals.