Nanostructured semiconductor surfaces induced by an electric field

Surfaces of single crystal [311] silicon, germanium and GaAs were nanostructured by a DC electric field (0.1-1.5-kV/cm). Spark threshold was found to be 1.33, 0.66 and 0.33-kV/cm for GaAs, silicon and germanium, respectively. Field nanostructuring results in the formation of nanoparticles of grain size in the range of 30-200-nm showed the nanoparticle size increasing with the increase in field value. Electric field treatment of the silicon surface gives rise to a lack of long-range crystalline order for surfaces. The effect of such a nanostructuring process is to make more absorbing and surface-oxidised nanocrystalline photoluminescent surfaces. Electric field treatment gives rise to local and directional nanostructuring.