Semiconductor device and manufacturing method thereof

A method of manufacturing a semiconductor device, comprising:

• forming two first semiconductor regions of which one is for a source region and another is for a drain region on a surface of a semiconductor substrate, stacking a gate insulating film and a gate electrode on the semiconductor substrate between the two first semiconductor regions, and forming a device isolation region to electrically isolate device formation regions in the two first semiconductor regions from the semiconductor substrate;
• forming a contact hole penetrating an interlayer insulating film and reaching at least one of the two first semiconductor regions in the interlayer insulating film;
• epitaxially growing a single-crystal first semiconductor layer in the contact hole;
• performing heat treatment after adhering a metal to the first semiconductor layer in the contact hole and forming a compound layer including a semiconductor in the first semiconductor layer and the metal on the first semiconductor layer;
• and
• forming a metal layer on the compound layer in the contact hole.