Semiconductor device and manufacturing method of semiconductor device

A semiconductor device comprising:

• a semiconductor substrate;
• a first layer formed of an oxide film provided on an upper surface of the semiconductor substrate;
• a second layer which is on an upper surface of the first layer and has a projection and a recess in an upper surface of the second layer, the projection and the recess comprising the recess being deeper than fine bumps in a first surface surrounding the projection and the recess;
• a barrier metal formed on the upper surface of the second layer according to a shape of the projection and the recess;
• and
• a pad in close contact with the second layer via the barrier metal.

A manufacturing method of a semiconductor device, comprising:

• forming a first layer being an oxide film, on an upper surface of a semiconductor substrate;
• forming a second layer on an upper surface of the first layer;
• forming a mask based on a pattern of a first projection and recess on an upper surface of the second layer;
• forming the first projection and recess on the second layer by an etching treatment based on the mask;
• removing the mask;
• film-forming a barrier metal on the upper surface of the second layer;
• and
• film-forming a metal which forms a pad on an upper surface of the barrier metal.