A lateral device structure such as used by Li et al. for XPS measurements can be a solution to avoid FIB milling. However, this could be impractical as spin-coating, often employed in PSC device preparation, will not allow for an X-ray transparent substrate that is necessary for STXM measurements. For bulk information specifically a thin film of appropriate thickness (not a full device), spin-coated or evaporated, can be easily investigated . It can be prepared on commercially available Silicon Nitride (Si3N4) windows. Figure (b) schematically shows a thin film sample prepared and mounted on a Si3N4 window for STXM analysis. In addition to this, Jun et al. have shown that a proper shadow mask on a lithographed substrate can be used to prepare planar films for in-situ biasing measurements in STXM. It is important to mention here that the company NORCADA Inc.