Selective adsorption of benzoic acid species on patterned OH/Si(100) surface

It has recently been observed that benzoic acid strongly reacts with OH group on the silicon surface. Here, by defining the area in which OH group is adsorbed on the Si surface, the selective adsorption of benzoic acid species was attempted. The patterned OH/Si surface was prepared by irradiating the zeroth order beam from the bending magnet of the synchrotron facility through the gold mesh placed in front of the OH/Si sample. For discerning the selectively adsorbed molecule by x-ray photoelectron emission microscopy (X-PEEM) at N k edge, 4-nitrobenzoic acid was utilized instead of benzoic acid. Near edge x-ray absorption fine structure spectra at carbon and oxygen k edges were in good accord with the previous results obtained from the benzoic acid system. The X-PEEM images around N k edge clearly showed that the molecules adsorb only on the area in which OH groups remain.