Patent ID: 6846722

Claim:
A method for isolating a hybrid device in an image sensor, the method comprising: forming sequentially a pad oxide layer and a pad nitride layer on a substrate and selectively removing a portion of the pad oxide layer and a first portion of the pad nitride layer to expose a surface of the substrate on which a field-insulation layer will be formed; forming a first ion-implantation region by performing a first ion-implantation process on the exposed surface of the substrate using the remaining pad nitride layer that exists after removal of the first portion of the pad nitride layer as a first mask; performing a thermal oxidation process to form the field insulation layer on the exposed surface of the substrate; removing a second portion of the pad nitride layer so that a side of the remaining pad nitride layer that exists after removal of the second portion of the pad nitride layer is spaced apart from an edge of the field insulation layer by a distance; and forming a second ion-implantation region by performing a second ion-implantation process on the field insulation layer using the remaining pad nitride layer that exists after removal of the second portion of the pad nitride layer as a second mask.