Structural and chemical analysis of ion beam produced conductive regions on highly resistive organic films

Journal Article · Thu Nov 15 04:00:00 EST 1984 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.333809· OSTI ID:6357998

Venkatesan, T; Forrest, S R; Kaplan, M L; Schmidt, P H; Murray, C A; Brown, W L; Wilkens, B J; Roberts, R F; Jr, Rupp L; Schonhorn, H

Thin films of both polymeric and nonpolymeric organic solids turn optically dense and electrically conductive on irradiation with high energy ion beams (e.g., 2 MeV Ar/sup +/). The structural and chemical properties of these films were investigated by ultraviolet (UV) visible, infrared (IR), Raman spectroscopic techniques, electron spin resonance (ESR), electron spectroscopy for chemical analysis (ESCA), and Rutherford backscattering (RBS) measurements. Specifically, in the case of 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) and nickel phthalocyanine (NiPc), and UV visible, IR, and Raman spectra show the loss of the initial molecular structure at low irradiation doses (10/sup 13/--10/sup 14/ cm/sup -2/) followed by the appearance, at high doses, of a spectrum similar to that observed for amorphous carbon. The Raman spectra indicate the absence of any long range graphitic microcrystalline structure and suggest that the films are nearly amorphous at higher doses. The RBS spectra indicate gradual loss of oxygen in PTCDA with increasing irradiation dose. There is negligible oxygen left in the film at high doses and a maximum loss of approx.35% (approx.15%) of the carbon atoms in PTCDA (NiPc) is observed. The resistivity of the films decreases with increasing dose, reaching a minimum of approx.5 x 10/sup -4/ ..cap omega.. cm at a dose of approx.10/sup 17/ Ar/sup +//cm/sup 2/. Surprisingly, the resistivity of these films at high doses (approx.10/sup 17/ Ar/sup +//cm/sup 2/) is considerably lower than that of any amorphous phase of carbon. In the case of NiPc, such a low resistivity is obtained even though 60% of the N and 100% of the Ni originally contained in the films are retained.

• Research Organization: AT and T Bell Laboratories, Murray Hill, New Jersey 07974
• OSTI ID: 6357998
• Journal Information: J. Appl. Phys.; (United States), Journal Name: J. Appl. Phys.; (United States) Vol. 56:10; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360406* -- Materials-- Polymers & Plastics-- Radiation Effects-- (-1987)
AMORPHOUS STATE
BACKSCATTERING
CHEMICAL PROPERTIES
COLLISIONS
CRYSTAL STRUCTURE
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELECTRON SPECTROSCOPY
ELECTRON SPIN RESONANCE
ENERGY RANGE
FILMS
INFRARED SPECTRA
ION COLLISIONS
LASER SPECTROSCOPY
MAGNETIC RESONANCE
MEV RANGE
MEV RANGE 01-10
MICROSTRUCTURE
OPACITY
OPTICAL PROPERTIES
ORGANIC COMPOUNDS
PHYSICAL PROPERTIES
PHYSICAL RADIATION EFFECTS
POLYMERS
RADIATION EFFECTS
RAMAN SPECTRA
RAMAN SPECTROSCOPY
RESONANCE
SCATTERING
SPECTRA
SPECTROSCOPY
THIN FILMS
ULTRAVIOLET SPECTRA
VISIBLE SPECTRA