Bardzo wysoka próżnia w aspekcie techniki epitaksji z wiązek molekularnych

The technology of thin films growth by molecular beam epitaxy can be realized by two methods: Solid Source MBE and Gas Source MBE. The main differences of these two methods consist in the quality and quantity of gases (vapors) flowing through the vacuum system of MBE equipments during crystal growth. The conditions of the preservation of MBE advantages: non-disturbing transport of mass from source in the direction of substrate and low concentration of the impurities in gaseous phase are discussed. The ability of various UHV pumps to longtime pumping of high fluxes of gases and vapors are also discussed. Some examples of in situ control of the gas phase during NH3-MBE processes by quadrupole mass spectrometer are shown including leak detection, degassing, growth of GaN films and oxygen impurity control.