  The possibility of modification of the local properties of hexagonal boron
nitride (h-BN) by laser irradiation is investigated. Investigations conducted
using both Raman spectroscopy and electrostatic force microscopy were
performed. Laser light induced modifications are found to cause no structural
changes. However, they have impact on Raman spectra and local charge state of
the material. They are also shown to be stable in time and during electrical
grounding of the sample. The mechanism of photoionization of deep defects
present in h-BN is proposed to explain the observed phenomenon. The discussed
effect opens up new method of nanostructurization of h-BN based planar
heterostructures.
