The present invention relates to a method of manufacturing a window transparent for electrons of an electron beam, in particular of an X-ray source. A gas mixture of HCl and H2O is introduced into the RF cleaning chamber and Ar gas plasma is generated in the RF cleaning chamber to excite HCl gas so that the HCl gas and an excited HCl gas are used to remove carbon radicals and metal particles. The system includes a distribution component operable when a caller system calls the called system to provide the multimedia content as ring back to the caller system. The wrapper tool intercepted the request and extracts information included in the intercepted request. The tag tracking system stores state records of position and informational content of the tag generated from the input. The heat exchanger unit generates heated air by transferring heat from the flow of water received from the faucet to air flowing through the heat exchanger unit.