Solid state imaging device for achieving enhanced zooming characteristics and method of making the same

A charge-coupled-device (CCD) solid state imaging device, comprising:

• a semiconductor substrate having a surface defined by an active area and a field insulating area;
• a plurality of light receiving parts arranged in a matrix of rows and columns within the active area of the surface of the semiconductor substrate;
• a plurality of vertical charge transfer stages which extend parallel to each other in a column direction and which are connected to adjacent respective columns of the plurality of light receiving parts;
• a horizontal charge transfer stage commonly connected to ends of the plurality of vertical transfer stages and formed in a horizontal transfer area, wherein the horizontal transfer area includes an insulating layer and a conductor formed sequentially over the surface of the semiconductor substrate, and a first impurity layer of a first conductivity type and a second impurity layer of a second conductively type formed sequentially under the surface of the semiconductor substrate;
• a barrier area located adjacent the horizontal transfer area and spaced from the field insulating area, wherein the barrier area includes the insulating layer and the conductor extending from the horizontal transfer area over the surface of the semiconductor substrate, a barrier area of the second conductivity type formed under the surface of the semiconductor substrate and adjacent the first impurity layer of the horizontal transfer area, and the second impurity layer extending from the horizontal transfer area and formed under the barrier area;
• and
• a discharge area located between the barrier area and the field insulating area, wherein the discharge area includes a field insulating layer interposed between the insulating layer and the conductor extending from the barrier area over the surface of the semiconductor substrate, and a discharge layer of the first conductivity type formed under the surface of the semiconductor substrate and adjacent the barrier area of the barrier area over the surface layer, and wherein an impurity concentration of the discharge layer is greater than that of the first impurity layer.