Apparatuses and processes for treating dielectric materials such as low k dielectric materials, premetal dielectric materials, barrier layers, and the like, generally comprise a radiation source module, a process chamber module coupled to the radiation source module; and a loadlock chamber module in operative communication with the process chamber and a wafer handler. The atmosphere of each one of the modules can be controlled as may be desired for different types of dielectric materials. The radiation source module includes a reflector, an ultraviolet radiation source, and a plate transmissive to the wavelengths of about 150 nm to about 300 nm, to define a sealed interior region, wherein the sealed interior region is in fluid communication with a fluid source.