Electrospun fibers have been applied to micro- and nano-devices, in which the controllability of the electrospinning area is critical. The current work is focused on depositing tin oxide nanofibers on a microhotplate. It demonstrates the feasibility of dampening the instability and decreasing the deposition area through the use of an auxiliary cylindrical electrode and a "near-field" technique. The micro gas sensor based on SnO(2) nanofibers is successfully fabricated by electrospinning poly (vinyl alcohol) (PVA)/SnCl(4)center dot 5H(2)O composite and proper annealing. The results of acetone vapor detection show that the sensor has a high sensitivity, a low detection limit (<10 ppb), and a fast response/recovery.