NOVELTY - The photovoltaic device comprises a single junction solar cell provided by an absorption layer (10) made of a type IV semiconductor material having a first conductivity, and an emitter layer (20) made of a type III-V semiconductor material having a second conductivity. The type III-V semiconductor material has a thickness of less than 10 nm. The absorption layer has a thickness of 100 nm to 1 mm. First and second dopants provide the n-type of the first conductivity and p-type of the second conductivity in the type IV semiconductor material respectively.    USE - Used as a single junction photovoltaic device.    ADVANTAGE - The single junction photovoltaic device exhibits high power generation efficiency, increased radiation stability and reduced dark currents.    DETAILED DESCRIPTION - The photovoltaic device comprises a single junction solar cell provided by an absorption layer (10) made of a type IV semiconductor material having a first conductivity, and an emitter layer (20) made of a type III-V semiconductor material having a second conductivity. The type III-V semiconductor material has a thickness of less than 10 nm. The absorption layer has a thickness of 100 nm to 1 mm. First and second dopants provide the n-type of the first conductivity and p-type of the second conductivity in the type IV semiconductor material respectively. A concentration of the first dopant is 109 to 1020 atoms/cm3. A concentration of the second dopant is 1015 to 1021 atoms/cm3. The first and second conductivities are n-type or p-type conductivities. The emitter layer is present in direct contact with the absorption layer or a buffer layer of the type III-V semiconductor material between the emitter layer and the absorption layer. The buffer layer is an intrinsic semiconductor. The photovoltaic device further comprises a first passivation layer (25) present on a first surface of the emitter layer that is opposite to a second surface of the emitter layer that forms a junction with the absorption layer, a transparent conductive oxide or a metal layer present on an exposed surface of the first passivation layer, and a second passivation layer (5) present on a surface of the absorption layer that is opposite to a surface of the emitter layer that forms the junction with the emitter layer. An INDEPENDENT CLAIM is included for a method of forming a photovoltaic device.    DESCRIPTION OF DRAWING(S) - The diagram shows a schematic side cross-sectional view of a single junction solar cell.    Second passivation layer (5)    Absorption layer (10)    Emitter layer (20)    First passivation layer (25)    Transparent conductive material layer. (30)