  We present a new method to obtain topological insulator Bi$_2$Se$_3$ thin
films with a centimeter large lateral length. To produce amorphous Bi$_2$Se$_3$
thin films we have used a sequential flash-evaporation method at room
temperature. Transmission electron microscopy has been used to verify that the
prepared samples are in a pure amorphous state. During annealing the samples
transform into the rhombohedral Bi$_2$Se$_3$ crystalline strcuture which was
confirmed using X-ray diffraction and Raman spectroscopy. Resistance
measurements of the amorphous films show the expected Mott variable range
hopping conduction process with a high specific resistance compared to the one
obtained in the crystalline phase (metallic behavior). We have measured the
magnetoresistance (MR) and the Hall effect (HE) at different temperatures
between 2 K and 275 K. At temperatures $T \lesssim 50$ K and fields $B \lesssim
1$ T we observe weak anti-localization in the MR; the Hall measurements confirm
the n-type character of the samples. All experimental results of our films are
in quantitative agreement with results from samples prepared using more
sophisticated methods.
