Semiconductor device and manufacturing method thereof

A method for manufacturing a semiconductor device, comprising:

• forming a dielectric layer over a substrate;
• forming a first pattern and a second pattern in the first interlayer dielectric layer, the first pattern having a width greater than a width of the second pattern;
• forming a first metallic layer in the first pattern and the second pattern;
• forming a second metallic layer in the first pattern and the second pattern;
• forming a third metallic layer in the first pattern;
• and
• performing a planarization operation on the first and second metallic layers so that a first metal wiring by the first pattern and a second metal wiring by the second pattern are formed, wherein:
• the first metal wiring includes the first and second metallic layers and the second metal wiring includes the first metallic layer but does not include the second metallic layer,
• the planarization operation includes:
• a first planarization operation, which stops at the first metallic layer;
• and
• a second planarization operation performed after the first planarization operation, by which parts of the dielectric layer and the first to third metallic layers are removed.