Patent ID: 7229878
Filing Date: 2007-06-12
Classification: H01L

Abstract:
1. A method for fabricating a phototransistor of a CMOS image sensor comprising: defining an active area and a device isolation area in a first conductive type semiconductor substrate by forming an STI layer in the first conductive type semiconductor substrate; forming a second conductive type well in the first conductive type semiconductor substrate, wherein the first conductive type is different from the second conductive type; forming a gate oxide layer on art entire surface of the first conductive type semiconductor substrate; forming a contact hole for exposing the predetermined portion of the second conductive type well below the STI layer by selectively removing the gate oxide layer and the STI layer; forming an ohmic contact layer by implanting second conductive type impurity ions into the second conductive type well below the contact hole using the gate oxide layer as a mask; forming a contact by filling the contact hole with a conductive material; and forming a gate line over the first conductive type semiconductor substrate including the contact.