Substrate processing apparatus and substrate processing method using the same

A substrate processing method, comprising:

• forming a seed layer on a first substrate on a first stage in a process chamber;
• moving the first substrate having the seed layer to a second stage in the process chamber;
• and
• forming a bulk layer on the first substrate on the second stage,
• wherein forming the seed layer on the first substrate comprises supplying the first substrate with a first gas in a first pulse,
• wherein the forming the bulk layer on the first substrate comprises supplying the first substrate with a second gas in a second pulse,
• wherein the supplying the first substrate with the first gas in the first pulse comprises:
• filling, with the first gas, a first gas supply unit upwardly spaced apart from the first stage, the first gas reaching a first pressure;
• and
• supplying the first substrate with the first gas introduced into the first gas supply unit,
• wherein the supplying the first substrate with the second gas in the second pulse comprises:
• filling, with the second gas, a second gas supply unit upwardly spaced apart from the second stage, the second gas reaching a second pressure;
• and
• supplying the first substrate with the second gas introduced into the second gas supply unit, and
• wherein the first pressure is less than the second pressure.