NOVELTY - Multi-junction solar cell (200) comprises many p-n junction solar cells connected in series with one another, where one of the solar cells comprises a dilute group III-V nitride solar cell (208) having contact blocking layers (210) formed on opposing sides of the p-n junction that prevent the passage of electrons in one direction from nitride solar cell into an adjacent layer of the multi-junction solar cell and prevent the passage of holes in an opposing direction from the nitride solar cell into an adjacent layer of the multi-junction solar cell.    USE - Used as multi-junction solar cell.    ADVANTAGE - The multi-junction solar cell utilizes group III-V nitride solar cell that exhibits a bandgap of 1 eV (claimed), thus overcoming low open circuit voltage and low current, and providing larger overall voltage output leading to improved performance.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for the dilute group III-V nitride solar cell comprising: the p-n junction formed by respective p-type (212) and n-type layers (214) of the nitride material, where each of the p-type and n-type layers possess an inner surface adjacent to a junction formed between the p-type and n-type layers and an outer surface on an opposite side of the p-type and n-type layers from the junction; a first contact blocking layer formed on the outer surface of the p-type layer; and a second contact blocking layer formed on the outer surface of the n-type layer, where the first and second contact blocking layers are arranged to prevent the passage of electrons in one direction from the nitride solar cell and prevent the passage of holes in an opposing direction from the nitride solar cell.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic block diagram illustration of the multi-junction solar cell.    Multi-junction solar cell (200)    Dilute group III-V nitride solar cell (208)    Contact blocking layers (210)    Layer containing p-gallium indium nitride arsenide or p-gallium nitride antimony arsenide (212)    Layer containing n-gallium indium nitride arsenide or n-gallium nitride antimony arsenide (214)