THE EFFECTS OF BORON CONTENT IN THE TARGET OF PULSED LASER DEPOSITION ON THE PROPERTIES OF BORON DOPED AMORPHOUS CARBON THIN FILMS

Abstract

The effects of boron content in camphoric carbon (CC) and graphite target of pulsed laser deposition (PLD) prepared in vacuum at room temperature on the properties of boron doped amorphous carbon (a-C:B) thin films has been studied. Deposited a-C:B films have been investigated using standard measurement techniques and the effects of B weight percentages (Bwt%) in the target are discussed. The variation of surface morphology, bonding and structural properties, as well as the optical gap (Eg) and electrical resistivity (ρ) of a-C:B films deposited using a CC target are related to the successful doping of B for low B content in the amorphous carbon (a-C) films as the structure and Eg remain almost unchanged, and the ρ decreased for the film deposited using graphite target with B powder up to 10 Bwt%. Since both Eg and ρ decreased sharply with higher Bwt%, this phenomenon may be due to graphitization. For a-C:B films deposited using graphite target with low B content at 1 and 3 Bwt%, as the Eg is observed to increase only slightly when compared with undoped a-C films and with the decrease of ρ, we speculated that the B incorporation induced successful of doping is responsible for the decrease in ρ.