Substrate processing apparatus, inner tube and method of manufacturing semiconductor device

Abstract

According to one aspect of a technique the present disclosure, there is provided a processing apparatus including: an inner tube provided with a substrate accommodating region in which substrates are accommodated along an arrangement direction; an outer tube provided outside the inner tube; gas supply ports provided on a side wall of the inner tube along the arrangement direction; first exhaust ports provided on the side wall of the inner tube along the arrangement direction; a second exhaust port provided at a lower end portion of the outer tube; and a gas guide for controlling a flow of gas in an annular space between the inner tube and the outer tube and including a first fin near a lowermost first exhaust port among the first exhaust ports that is closest to the second exhaust port in a space between the lowermost first exhaust port and the second exhaust port.