Semiconductor device, semiconductor module, and method of manufacturing semiconductor device

A semiconductor device comprising:

• a semiconductor substrate having a main surface;
• an interlayer insulating film provided on the main surface of the semiconductor substrate;
• a contact hole penetrating through the interlayer insulating film to reach the semiconductor substrate;
• a plug electrode embedded in the contact hole;
• a first barrier metal provided on the interlayer insulating film;
• a second barrier metal provided between a side surface of the plug electrode and the interlayer insulating film;
• a third barrier metal provided between the plug electrode and the semiconductor substrate;
• and
• a front electrode provided on the first barrier metal, wherein
• a top of the plug electrode is free of the first barrier metal, and
• the first barrier metal, the second barrier metal, and the third barrier metal have different compositions.

A method of manufacturing a semiconductor device, the method comprising:

• as a first process, preparing a semiconductor substrate and depositing an interlayer insulating film on a main surface of the semiconductor substrate;
• as a second process, forming a contact hole penetrating through the interlayer insulating film to reach the semiconductor substrate;
• as a third process, depositing a plug electrode on the interlayer insulating film and in the contact hole;
• as a fourth process, removing the plug electrode on the interlayer insulating film while leaving the plug electrode only in the contact hole;
• as a fifth process, depositing a first barrier metal on the plug electrode and the interlayer insulating film;
• as a tenth process, removing the first barrier metal on the plug electrode while leaving the first barrier metal only on the interlayer insulating film;
• and
• as a sixth process, depositing a front electrode on the first barrier metal,
• said first to sixth processes being performed in sequence as mentioned.