▎ 摘　　要

NOVELTY - The device has a low resistance light gain semiconductor substrate (1) on which an insulating layer (2) is formed. The opening of the insulating layer exposes a portion of the semiconductor substrate. A portion of a graphene layer (3) is located in the opening of low semiconductor substrate and the other portion is located on insulating layer. A portion of first electrode (41) is in contact with the low resistance light gain semiconductor substrate and other portion is in contact with graphene layer. A second electrode (42) is located on insulating layer and graphene layer. USE - Photovoltaic device used in micro-nano device. ADVANTAGE - The photovoltaic device is simple in structure and small in size, and has potential application in the the flexible device. The large amount of photogenerated carriers generated in the low-resistance light-gain semiconductor material are rapidly transferred to the irradiated graphene and the electrode, such that a Fermi level difference is established between the irradiated and non-irradiated electrodes at both ends of the graphene, thus achieving a photovoltaic effect and high photoelectric conversion efficiency. In the short-circuit conditions, the ultra-fast response is provided to radiation and sensitive detection due to excellent electronic transport characteristics of graphene. Thus the photovoltaic device can be used as an ultrafast, sensitive photodetector without power supply. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for method of generating a photovoltaic effect using the photovoltaic device. DESCRIPTION OF DRAWING(S) - The drawing shows a top view of the photovoltaic device. Low resistance light gain semiconductor substrate (1) Insulating layer (2) Graphene layer (3) First electrode (41) Second electrode (42)