Semiconductor device having element isolating insulating film in contact hole

Abstract

A semiconductor device is obtained which can suppress decrease in contact area between an interconnection layer and a semiconductor substrate. Further, a method of manufacturing a semiconductor device which can increase in contact resistance between first and second interconnection layers can be obtained. In the semiconductor device, upper surface of an element isolating insulating film is removed near a boundary point between the element isolating oxide film and the semiconductor substrate. Consequently, the surface of the semiconductor substrate is exposed where the element isolating insulating film has been removed. Since a conductive layer is formed to be in contact with the exposed semiconductor substrate, contact area between the conductive layer and the semiconductor substrate is increased. In the manufacturing method of the semiconductor device, foreign matters on the first interconnection layer derived from wet etching using hydrofluoric acid solution is removed by anisotropic dry etching, and thereafter a second interconnection layer is formed on the first interconnection layer.

Dependencies are inferred from the claim text.