A furnace includes a section defined as a heating section capable of attaining a predetermined temperature, the heating section having an entrance end and an exit end; a section defined as a cooling section capable of having a temperature gradient from entrance end of the cooling section to exit end of the cooling section, the entrance end of the cooling section mounted in a fixed relationship to the exit end of the heating section; a section defined as an edge cooling section between the exit end of the heating section and the entrance end of the cooling section; and an edge cooling device positioned in the edge cooling section relative to a predetermined area, and capable of cooling at least selected peripheral portions of the predetermined area at a faster rate than center portions of the predetermined area.