the first step in the fabrication of silicon based electronic devices, silicon substrates are subjected to a complex processing that include chemical etching to remove its native silicon dioxide and its surface passivation. one of the processing steps uses diluted hydrofluoric acid (hf) and deionized water (h 2 o). usually, xps is used to determine the presence of any remaining fluorine contaminations, their bonding configurations and optimize the chemical etching process. 1. xps is used to characterize si 2p photoelectrons. which one of the following bonds has higher binding energy and why: si-h or si-f. justify your answer. 2. the binding energies of the "f 1s " and "f 2s " photoelectrons for fluorine are 686 ev and 31 ev respectively. explain why the binding energy for 1s electrons is stronger than the "2s" electrons.