Abstract
Surface roughness of GaSb-cells was investigated under various conditions of manufacturing procedure to achieve nano-gap thermophotovoltaic generation of electricity through evanescent wave appeared in the vicinity of emitter surfaces. The morphology is changed from 3D-structure to 2D when the beam equivalence pressure ratio (BEP) Sb_4/Ga is more than about 4. The root mean square (RMS) of surface roughness is about 10 nanometer and it becomes smaller with decreasing substrate-temperature.
