Embodiments of a semiconductor processing apparatus are provided. The semiconductor processing apparatus includes a housing and a support base disposed in the housing. The semiconductor processing apparatus also includes a carrying arm movably disposed on the support base and a nozzle device disposed on the carrying arm. The semiconductor processing apparatus further includes a wafer plate disposed on the support base. When a cleaning process is performed, the carrying arm is moved toward the wafer plate, and the nozzle device emits a first gas toward the support base and the wafer plate.