Method for preparing Ge photoelectric detector with transverse p-i-n structure

The invention discloses a method for preparing a Ge photoelectric detector with a transverse p-i-n structure, and relates to the germanium photoelectric detector. The method comprises the steps of (1) carrying out epitaxial growth of a monocrystalline germanium layer on a substrate, growing a SiO2 covering layer on the monocrystalline germanium layer, (2) using a micro-electronics photolithography to etch an active area platform surface of a long and thin strip shape on the epitaxial monocrystalline germanium layer, (3) using the SiO2 covering layer on the monocrystalline germanium layer for masking, forming a doped p area and a doped n area on the two sides of the platform surface respectively through sidewise large-declination ion implantation, (4) carrying out thermal annealing after deposition of a metal Ni layer, forming NiGe contact electrodes and NiSi contact electrodes on the two sides of the platform surface and the bottom of the etched area through a self-alignment technology used in the forming process of NiGe and NiSi, and (5) leading out the device electrodes, and protecting a passivating layer. Therefore, the Ge photoelectric detector with the transverse p-i-n structure is obtained. The technology is simple, operability is high, and high application value is achieved.