Provided are a semiconductor substrate manufacturing apparatus and a substrate treating method, and more particularly, an apparatus and method for performing a reflow treating process on a semiconductor wafer. The apparatus treating apparatus includes a load port on which a carrier accommodating a substrate is seated, a substrate treating module including one reflow treating unit or a plurality of reflow treating units for performing a reflow process on the substrate, and a substrate transfer module including a transfer robot transferring the substrate between the load port and the substrate treating module, the substrate transfer module being disposed between the load port and the substrate treating module. The reflow treating unit includes a process chamber having a treating space therein and an exhaust member exhausting a fluid within the process chamber. The exhaust member includes a plurality of individual exhaust lines connecting a plurality of process chambers to each other and a common exhaust line connected to the plurality of individual exhaust lines to exhaust the fluid to the outside of the substrate treating module.