C1s spectra taken at 330 eV for: (a) clean H-terminated diamond and (b)–(f) selected C60F48 coverage between 0.066 ML and 1.0 ML.
Surface band bending (EF – EVBM) as a function of C60F48 coverage. The data points contain correction to the C1s binding energy as described in the text. The error bars on the data points give the uncertainties in the measured Fermi level shift; the large error bar on the dashed line reflects the systematic uncertainty in the EVBM – EC1s separation.
C1s spectra taken at 330 eV for O-terminated diamond with 0.2 ML and 0.5ML C60F48 coverages.
Relative intensities as a function of coverage of the two components: doping () and non-doping (N A ) that make up the C=C and C–F spectral regions of the C1s spectrum of C60F48 on diamond.
Binding energy of the (C=C)− doping line as a function of C60F48 coverage. Closed squares: relative to EF and open circles: relative to the VBM of diamond.
The increase in acceptor energy Δ = ELUMO – EVBM relative to the initial value Δ0 as a function of coverage (open squares). Also plotted is the variation in interface potential ΔΦ as calculated in the capacitor model (open circles).
EF – EVBM as a function of hole sheet density for atmosphere (closed squares) and C60F48 (open circles) surface conductivity taken from the work of Edmonds et al. 17 The solid line is a polynomial fit of the data to obtain the function w(p).
Doping efficiency as a function of hole density for initial activation energies Δ0 ranging from 0 eV to –1 eV.
Experimentally and theoretically determined hole density as a function of C60F48 coverage. Open circles represent the hole sheet density determined using the values of EF – EVBM in Fig. 2 and the band bending function w(p). Open squares represent the number of doping C60F48 molecules at each coverage calculated from the relative intensities of the fluorofullerene core level components. The dashed and solid lines correspond to the hole density calculated using Eq. (4) with initial activation energies of –0.5 eV and –0.7 eV, respectively.
Band diagram for C60F48 on diamond: (a) in the limit of vanishing concentration and (b) 1 ML C60F48 coverage.
Binding energy and relative intensity of the line components for selected C60F48 coverages.
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