Abstract: The invention provides generally a method and an apparatus for in situ cleaning of a surface in a semiconductor substrate processing chamber which operates quickly and reduces the downtime for chamber cleaning. The apparatus comprises an ultraviolet (UV) radiation plate moveable between a cleaning position and a storage position and at least one UV radiation source disposed on the UV radiation plate. Preferably, the apparatus includes a reflector disposed adjacent the UV radiation source to focus emitted UV radiation and a rotary actuator pivotally attached to a transport arm to move the UV radiation plate between the cleaning position and the storage position. The method comprises: providing a UV radiation plate having at least one UV radiation source disposed thereon, moving the UV radiation plate into a cleaning position, introducing a cleaning gas into the processing chamber and exposing the surface to UV radiation.