N⁺ beam induced nano-cluster formation in poly(2,6-dimethyl phenylene oxide) thin films

We report the energetic N+ (100 keV) implantation effect on the spin cast film of poly(2,6-dimethyl phenylene oxide) [PPO] and formation of ion beam induced crystalline nano-clusters, for the first time. Evidence for the formation of highly oriented clusters of ∼ 22 nm size is obtained from grazing incidence XRD (GIXRD) analysis of the implanted PPO films with a fluence of 6 × 1016 ions/cm2 whereas the as-deposited film is found amorphous. All the characteristic Raman peaks of PPO film disappears and subsequently a broad peak at 1500 cm-1 in the FT-Raman spectrum appears implying the presence of graphite like carbon (GLC) in the implanted polymer. DC conductivity behaviour in the implanted sample has shown the dominant role of three dimensional (3-D) variable range hopping (VRH) mechanism in the temperature range of 303-500 K. The role of clusters is discussed in analysing the current transport mechanism in the implanted polymer. © 1999 Elsevier Science B.V. All rights reserved.