PHOTOLUMINESCENCE STUDY OF DEEP ETCHED INGAAS GAAS QUANTUM WIRES AND DOTS DEFINED BY LOW-VOLTAGE ELECTRON-BEAM LITHOGRAPHY/

Combining low-voltage electron beam lithography (EEL) and wet chemical etching, arrays of deep etched InGaAs/GaAs quantum wires with widths down to 15 nm and dots with minimum diameters of 27 nm have been fabri cated. The application of low-voltage EEL strongly reduces the proximi ty effect during pattern exposure and allows the formation of very hom ogeneous nanostructure arrays. Low-excitation photoluminescence (PL) s pectroscopy of both wires and dots reveals a structure size dependent blue shift of the emission lines up to 14 meV. This energy shift is ca used by lateral confinement and shows a clear dependence on the struct ure dimensionality. The quantization is calculated with a simple model using only standard InGaAs/GaAs material parameters and the geometric al structure widths measured with a scanning electron microscope (SEM) . (C) 1996 American Institute of Physics.