Dynamic High Pressure

XPS and AES suffer from a limitation of the operating pressure, that must be in the high vacuum or ultra high vacuum range. The state-of-the-art approach to increase the base pressure up to ambient condition for spectroscopy relies on unique and expensive set-ups based on sophisticated differentially pumped electron lenses. The first attempts to adapt them to photoemission microscopes are promising but require for their development rather complicated technology. Here we describe the Dynamic High Pressure (DHP) system developed and implemented in the SPEM instrument at Elettra. This setup is a solution adaptable to existing XPS spectroscopes and microscopes, which controls the amount of gas injected into the chamber by fine tuning both spatial and time profile of a gas jet directed toward  the sample without exceeding the pressure limits required for XPS measurements. Burst of pressure in the millibar range and few millisecond long are achievable. We believe it can represent a valid option for extending the maximum in operando allowable pressure for defined classes of experiments.