Semiconductor device and manufacturing method of the same

A semiconductor device comprising:

• a first wiring layer disposed on a semiconductor substrate;
• a first insulating layer disposed on the first wiring layer and having a first opening formed therein;
• a first metal layer embedded in the first opening so as to be connected to the first wiring layer;
• a second wiring layer disposed on the first insulating layer so as to be connected to the first metal layer;
• a second insulating layer disposed on the second wiring layer and the first insulating layer and having a second opening formed therein, the second opening covering the first opening;
• a third wiring layer disposed on the second insulating layer so as to be connected to the second wiring layer through the second opening;
• and
• an alloy layer disposed between the second and third wiring layers and made of metals of the second and third wiring layers,
• wherein the third wiring layer comprises a chromium layer and a copper layer disposed on the chromium layer, grains of a first portion of the chromium layer located directly above the first metal layer are more loosely packed than grains of a second portion of the chromium layer located not directly above the first metal layer so that the grains of the first portion have wider spaces between them than the grains of the second portion, and the alloy layer is formed in the wider spaces among the grains of the first portion of the chromium layer.

A semiconductor device comprising:

• a first wiring layer disposed on a semiconductor substrate;
• a first insulating layer disposed on the first wiring layer and having a plurality of first openings formed therein;
• a barrier metal film comprising titanium, covering bottoms and sidewalls of the first openings and covering a top portion of the first insulating layer;
• a plurality of first metal layers comprising tungsten and embedded in corresponding first openings covered by the barrier metal film;
• a second metal layer comprising aluminum and in contact with the first metal layers embedded in the first openings and in contact with the barrier metal layer disposed on the top portion of the first insulating layer;
• a second insulating layer disposed on the second metal layer and the first insulating layer and having a second opening formed therein, the second opening covering the first openings;
• a third metal layer comprising chromium disposed in the second opening so as to be in contact with the second metal layer;
• and
• a fourth metal layer comprising copper and in contact with the third metal layer in the second opening,
• wherein an alloy layer made of the metals of the second and fourth metal layers is formed non-uniformly in the third metal layer so that the alloy layer is formed above the first opening but is not formed horizontally away from the first opening.