Gas injection apparatus and substrate processing apparatus

Abstract

A gas injection device according to one aspect of the present invention includes: a top plate having a gas inlet formed at its center; and an injection plate, coupled to the top plate, forming a plurality of injection holes for injecting gas supplied to the gas inlet, wherein the injection plate includes a first region within a first circle of a first radius centered thereon, and second to nth regions sequentially defined from the outside of the first circle by second to nth circles having the same center as the first circle and having radii gradually increasing from the first radius to the nth radius, wherein a plurality of injection holes arranged circumferentially within each of the second to nth regions form a plurality of rings.