Photoionization mass spectroscopy flux monitor

摘要

The present invention provides a photoionization mass spectroscopy flux monitor for gaseous species above a sample surface. It provides an in situ, real time, species specific, nonintrusive probe with a geometry compatible with conventional MBE growth chambers. Gaseous species are photoionized above a sample surface and the ionized gaseous species are extracted parallel to the sample surface and coupled into a mass spectrometer inlet adjacent to the sample surface. The geometry of the flux monitor allows for simultaneous coupling of a charged particle beam with the sample surface, for example for monitoring film growth with RHEED.