In this report we study the morphology and chemical composition of a nanocomposite memory device where the active device layer is sandwiched between two aluminum electrodes and consists of a nanocomposite of polystyrene (PS) and [6,6]-phenyl-C61 butyric acid methyl ester (PCBM). The morphology of the active layer is imaged both in plan-view and cross-sectional view by using transmission electron microscopy (TEM). We introduce two techniques to prepare the cross-sections from the active layer, namely, a conventional technique based on microtoming and secondly nanostructural processing with focused ion beam (FIB). Based on the morphology studies we deduce that within the used concentrations the PCBM forms spherical nanoscale clusters within the continuous PS matrix. The chemical composition of the device is determined by using X-ray photoelectron spectroscopy (XPS) and it shows that the thermal evaporation of the aluminum electrodes does not lead to observable inclusion of the aluminum into the active material layer.