TransitionMetal mechanical property Trench Sapphire CuSubstrate Hole Hafnium_dioxide HiVacuum Imprint Fluoride atomic_layer LeakageCurrent Layer non_contact MoirePattern Praseodymium PDMS solar_cell self_assembly TappingMode STO small_scan NUS_NNI_Nanocore Steps NUS_Physics ElectroDeposition GaAs epitaxy Lift Pore PolymerBlend Lateral HighAspect Sadowski HumanHair