UTEM TappingMode align Adhesion StrontiumTitanate Zagreb LFM ring shape MechanicalProperty Aluminium_Oxide block_copolymer Pore Vinylpyridine molecule chemical_compound BlockCopolymer Organic Worcester_Polytechnic_Institute Sapphire AdhesionForce Litho Vac SurfaceChange Titanate Transparent Blend Praseodymium Polarization Chrome mono_layer hetero_structure SThM LeakageCurrent Photovoltaics SingleLayer