NOVELTY - A photoelectric conversion device (1) comprises a photoelectric conversion semiconductor layer (30) mainly composed of compound semiconductor containing group Ib element, two group IIIb elements including gallium (Ga), and group VIb element and contains alkaline-earth metal, where concentration distributions of alkaline-earth metal and Ga in photoelectric conversion layer in the thickness direction includes a valley with lowest concentration and an area with a higher concentration between a substrate (10) and valley, and satisfy equations (I) and (II) as given in the specification.    USE - As photoelectric conversion device used in a solar battery (claimed) and in infrared sensors.    ADVANTAGE - The photoelectric conversion device has a concentration distribution of the alkaline-earth metal in the photoelectric conversion layer in the thickness direction that is optimized according to the concentration distribution of gallium in the thickness direction, thus has less defects causing a loss in photoelectric conversion in the photoelectric conversion layer, and thus has high photoelectric conversion efficiency. Moreover, the amount of the alkaline-earth metal to be supplied and the state of diffusion are optimized according to the concentration distribution of gallium in the thickness direction, thus the method produces highly efficient photoelectric conversion devices in a stable manner.    DETAILED DESCRIPTION - A photoelectric conversion device (1) comprises: a layered structure formed on a substrate (10), where the layered structure comprises a first electrode (20), a photoelectric conversion semiconductor layer (30) for generating an electric current when it absorbs light, and a second electrode (50), where the photoelectric conversion semiconductor layer comprises, as a main component, at least one compound semiconductor comprising a group Ib element, at least two group IIIb elements including gallium (Ga), and a group VIb element, and comprises at least one alkaline-earth metal, where a concentration distribution of the alkaline-earth metal in the photoelectric conversion semiconductor layer in a thickness direction comprises a valley position with a lowest concentration of the alkaline-earth metal and an area with a concentration of the alkaline-earth metal higher than the concentration at the valley position, the area is nearer to the substrate from the valley position, a concentration distribution of Ga in the photoelectric conversion semiconductor layer in the thickness direction comprises a valley position with a lowest concentration of Ga and an area with a concentration of Ga higher than the concentration at the valley position, the area is nearer to the substrate from the valley position, and satisfies the equations 1.0x 10-6 less than or equal to An (mol/cc) less than or equal to 2.0x 10-5 (I) and 1.0 less than or equal to Cn/Cg (II), where with respect to the concentration distribution of the alkaline-earth metal in the thickness direction in the photoelectric conversion semiconductor layer, An (mol/cc) represents the concentration of the alkaline-earth metal at the valley position and Bn (mol/cc) represents a highest concentration of the alkaline-earth metal at a position nearer to the substrate from the valley position; with respect to the concentration distribution of Ga in the thickness direction in the photoelectric conversion semiconductor layer, Ag(mol/cc) represents the concentration of Ga at the valley position and Bg (mol/cc) represents a highest concentration of Ga at a position nearer to the substrate from the valley position; Cn represents a ratio (Bn/An) between An and Bn, and Cg represents a ratio (Bg/Ag) between Ag and Bg. An INDEPENDENT CLAIM is included for producing the photoelectric conversion device involving: forming the photoelectric conversion semiconductor layer through vapor deposition by depositing several metal elements in several steps at a substrate temperature of 350 to 550 degrees C.    DESCRIPTION OF DRAWING(S) - The figure shows a sectional view illustrating the structure of a photoelectric conversion device.    Photoelectric conversion device (1)    Substrate (10)    First electrode (20)    Photoelectric conversion semiconductor layer (30)    Second electrode (50)