  Recently, ZrTe$_5$ has received a lot of attention as it exhibits various
topological phases, such as weak and strong topological insulators, a Dirac
semimetal, and a quantum spin Hall insulator in the monolayer limit. While most
of studies have been focused on the three-dimensional bulk material, it is
highly desired to obtain nanostructured materials due to their advantages in
device applications. We report the synthesis and characterizations of ZrTe$_5$
nanoribbons. Via a silicon-assisted chemical vapor transport method, long
nanoribbons with thickness as thin as 20 nm can be grown. The growth rate is
over an order of magnitude faster than the previous method for growth of bulk
crystals. Moreover, transport studies show that nanoribbons are of low
unintentional doping and high carrier mobility, over 30,000 cm$^2$/Vs, which
enable reliable determination of the Berry phase of $\pi$ in the $ac$ plane
from quantum oscillations. Our method holds great potential in growth of high
quality ultra-thin nanostructures of ZrTe$_5$.
