A heating chamber which can be used during a reflow process to form a metal wiring having a multi-layered writing structure and a method of heating a wafer using the same, are provided. The heating chamber is movable upward and downward between the upper process position and the lower loading position, and includes a pedestal having a supporting surface for supporting a wafer, a cover installed above the pedestal to form a processing area together with the supporting surface when the pedestal is placed in its raised process position and a heating unit for heating the waver. In the method of heating the wafer, the temperature in the processing area is maintained suitable for heating the wafer before the wafer is loaded onto the supporting surface, the wafer is loaded onto the supporting surface and the loaded wafer is heating in the processing area.