NOVELTY - The solar cell or semiconductor device comprises a base, a doped, nanostructured layer formed on the base, a passivation layer (144), and a transparent conductor layer. The nanostructured layer includes a nanostructured surface opposite to the base. The nanostructured surface comprises a quasiperiodic, anisotropic array of elongated ridge elements having a wave-ordered structure pattern. Each ridge element has a wavelike cross-section, and is oriented in a first direction. The nanostructured layer is an emitter layer, a front surface field layer, or a back surface field layer.    USE - Used as a solar cell or semiconductor device.    ADVANTAGE - The solar cell or semiconductor device exhibits high conversion efficiency, increased performance, and improved reliability.    DETAILED DESCRIPTION - The solar cell or semiconductor device comprises a base, a doped, nanostructured layer formed on the base, a passivation layer (144), and a transparent conductor layer. The nanostructured layer includes a nanostructured surface opposite to the base. The nanostructured surface comprises a quasiperiodic, anisotropic array of elongated ridge elements having a wave-ordered structure pattern. Each ridge element has a wavelike cross-section, and is oriented in a first direction. The nanostructured layer is an emitter layer, a front surface field layer or a back surface field layer, and further includes a flat surface adjacent to the base. The passivation layer is disposed over a portion of the nanostructured surface. A reflection coefficient of the nanostructured surface is less than 2% in a light wavelength of 400-900 nm. The transparent conductor layer is formed over the nanostructured surface. A planar junction is positioned between the nanostructured layer and the base. An average period of the array is 20-200 nm. A ratio of average height of the ridge elements to the average period of the array is 2-3. Each ridge element further has a width, near its peak, of less than 10 nm. The nanostructured layer comprises silicon doped with a first dopant of a first conductivity type such as an n-type. A base is doped with a second dopant of a second conductivity type different from a first conductivity type. The doped layer has a thickness of less than 10 nm. An INDEPENDENT CLAIM is included for a method for making a semiconductor device.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic cross-sectional view of a solar cell.    Nanoridges (24)    Low doped emitter layer (143)    Passivation layer (144)    Contacts (145)    Metallization layer. (157)