An A1203 membrane regulates layer growth in the aluminium induced layer exchange (ALILE) process that is used for seed layer growth on flat substrates for photovoltaic (PV) applications. Due to the use of the energy loss near edge structure (ELNES) separation method, we now are able to separate the signal of oxygen influenced and uninfluenced material in electron energy loss spectrometry (EELS). We show that the aluminium of the membrane can be found as aluminium (III) oxide and that the Si of the seed layer remains untouched by the oxygen.