A generator for processing gases to be delivered to a process chamber used to process a substrate includes a housing that encloses an internal volume. An ultraviolet (UV) bulb is disposed within the internal volume of the housing. The UV bulb has a bulb diameter that fits within the internal major dimension of the housing. A first region, which surrounds the UV bulb, channels a first gas around the UV bulb to cool the UV bulb. A second region, which surrounds the first region, channels a second gas between an input to and an output from the housing. The second region is oriented relative to the UV bulb such that UV energy therefrom interacts with the second gas as this gas flows through the second region. The interaction of the UV energy with the second gas results in the generation of a gas mix that is supplied from the output of the housing into the process chamber, where at least one component of the gas mix is to be used in processing of the semiconductor substrate.
