MANUFACTURING METHOD OF PHOTO DIODE FOR PHOTO-FIBER COMMUNICATIONS

摘要

The method for removing leakage current to decrease dark current comprises the steps of growing an i-GaInAs layer (2) and a p-GaInAs layer (3) on an n-InP substrate (1) to form a pn junction, carrying out a lithographic process to perform a mesa etching, coating a polyimide layer (4) thereon to complete a passivation of the exposed pn junction part, depositing a SiO2 film (5) onto the layer (4), patterning the SiO2 film (5) and polyimide layer (4) by using the lithography, etching and plasma ashing processes, removing the film (5) by using buffered oxide etchant, and forming an electrode pad (6) on the polyimide (4) by using a lift-off method, thereby protecting the pn junction region to remove the leakage current.