  Amorphous VO$_x$ films without a hysteretic phase transition are stable with
respect to thermal cycling and highly demanded as sensitive elements of the
resistive thermometers and microbolometers. In this paper we present simple and
low-temperature growth of amorphous vanadium oxide films by reactive electron
beam evaporation of vanadium metal in $\sim 10^{-4}$ mBar oxygen atmosphere.
The temperature coefficient of the resistivity (TCR) of the films is weakly
sensitive to substrate material and temperature and could be tuned by oxygen
pressure in the growth chamber up to -2.2\% /K. The resistivity value is stable
for months. It depends on the substrate material and substrate temperature
during the evaporation. Simplicity and controllability of the method should
lead to various laboratory and industrial applications.
