Fig. 3: Extreme ultraviolet (EUV) photon energy bandwidth for hydrogen desorption.
From: EUV-induced hydrogen desorption as a step towards large-scale silicon quantum device patterning
a Si 2p photoelectron spectrum taken after 80 min photon irradiation using non-monochromatic (NMC) light without (w/o) and with three different EUV filters from a Si(001):H surface. A zoom-in of the single dangling bond component is shown by the arrow. b Plot of the density of up-buckled silicon atoms, ρSi,up, as a function of photon irradiation time (symbols), along with their best fits (lines). Each filter is labelled along with its comparative desorption rate relative to its unfiltered value. c Plot of the calculated (solid lines) and experimental (symbols) transmission curves for each EUV filter. The green region spans the photon energy range 100–210 eV where the transmission profile is such that Al < Zr < C; this coincides with the observed desorption rates in (a, b) and represents the photon energy regime responsible for the hydrogen desorption. The arrows indicate the threshold energy of the Si 2p and Si 2s core-levels, which lie within the green region. d Si 2p photoelectron spectrum taken after 900 min photon irradiation using monochromatic (MC) light at 109 eV. A zoom-in of the hydrogenic component is shown; the arrow indicates a very small decrease, due to hydrogen desorption. e Log-log plot of the desorption rate, νdes., as a function of incident photon intensity, Iph. The shaded area around the fit represents the 90% confidence interval. The NMC exposures are shown for both 77 K and RT, whereas the filtered NMC and MC exposures are at RT. The solid and dashed lines show the best fit for an exponent that equals 3/4 (sub-linear) and 1 (linear), respectively.
