Precursor supply unit, substrate processing system, and method of fabricating semiconductor device using the same

A method of fabricating a semiconductor device, comprising:

• providing a precursor and a carrier gas on a substrate in a chamber;
• and
• providing a reaction gas, which is reacted with the precursor, on the substrate to form a thin film on the substrate through reaction with the precursor,
• wherein the providing the precursor and the carrier gas comprises:
• supplying the carrier gas into a precursor passage space between a supporting membrane of an inner container and an inner bottom surface of an outer container, the inner container containing a precursor source;
• providing the carrier gas to the precursor source on the supporting membrane through pores of the supporting membrane;
• and
• obtaining the precursor through the pores using the carrier gas, without a reduction in supply pressures of the carrier gas and the precursor according to consumption of the precursor source in the inner container.