Electrical and Structural Characterization of 100 keV N+ Ion Implanted Kapton-H polyimide

Kapton-H polyimide implanted with 100 keV N+ ions at the fluence ranging from 1x10(15) to 5x10(16) ions/cm(2) has been characterized through V-I measurement, FTIR and Raman spectroscopic techniques. It has been found that the current increases with the increase of the voltage as well as with increasing ion fluence. The slope of the log (I) - log (V) plots for the highest implanted dose indicates the almost ohmic conduction behaviour in the N+ implanted Kapton-H. In FTIR-ATR spectra, the intensity of all the vibrational bands monotonically decreased which shows the breaking of various bonds as a result of ion implantation. Further, the Lorentzian fitting among the two bands observed in the Raman spectrum of Kapton-H implanted at the fluence of 5x10(16) N+/cm(2), depicts their centers at positions 1383 cm(-1) and 1566 cm(-1) with their intensity ratio (I-D/I-G) similar to 0.45. These peak positions and their intensity ratio mark the presence of D and G bands of carbonaceous materials. Thus, the observed changes in electrical behaviour may be attributed to the formation of a cross-linked conjugated carbonaceous structure in the near surface region of Kapton-H after N+ ions implantation.