Bipolar visible light detector and preparation method thereof

The invention relates to a bipolar visible light detector and a preparation method thereof. The bipolar visible light detector comprises a substrate, an epitaxial layer and a deposited metal electrode, a nucleating layer, a transition layer, a Si-doped n-type GaN lower ohmic contact layer, a Si-doped n-type Al < x > Ga < 1-x > N component gradient layer, an unintentionally doped AlGaN layer, an unintentionally doped AlGaN component gradient layer, an unintentionally doped InGaN light absorption layer with a periodic GaN thin insertion layer, a Si-doped n-type InkGa1-kNcomponent gradient layer and a Si-doped n-type GaN upper ohmic contact layer are sequentially grown on the epitaxial layer from bottom to top, the metal electrode comprises a lower ohmic contact electrode and an upper ohmic contact electrode. The invention has the advantages of high photoelectric gain, high response speed and low working voltage. 本发明涉及一种双极型可见光探测器及其制备方法，双极型可见光探测器包括衬底、外延层、沉积的金属电极，外延层按照自下而上的生长顺序依次为成核层、过渡层、Si掺杂n型GaN下欧