A single mode optical fiber having a core made from silica and less than or equal to about 6.5 weight % germania and having a maximum relative refractive index Δ1MAX. The optical fiber also has an inner cladding surrounding the core and having a minimum relative refractive index Δ2MIN. A difference between a softening point of the core and a softening point of the inner cladding is less than or equal to about 20° C., and Δ1MAX>Δ2MIN. The single mode optical fiber may also have an outer cladding surrounding the inner cladding made from silica or SiON. The outer cladding has a maximum relative refractive index Δ3MAX, and Δ3MAX>Δ2MIN. A method for manufacturing an optical fiber includes providing a preform to a first furnace, the preform, drawing the optical fiber from the preform, and cooling the drawn optical fiber in a second furnace.