COOLING a scanning tunneling microscope UHV

摘要

Coolant ultrahigh vacuum scanning tunneling microscope can be used during cryovacuum studies. The system is mounted on the flange ultrahigh vacuum chamber and comprises a helium reservoir located above them the upper and lower heat exchangers. Each of the heat exchangers is in the form of two flat discs with internal slit passage therebetween. Helium tank with heat exchangers and Gulf systems and evaporation of helium enclosed in placed in each other screens in the form of coaxially arranged hollow cylinders. The side walls of the helium tank are made double and have a gap provided with a tube for evacuating. evaporation of helium and system for ensuring the rigidity of the construction system are combined and executed as tubes, connecting pairs flange and the upper heat exchanger, the upper and lower heat exchangers, the heat exchanger and the lower helium vessel. Entrance to each of the heat exchangers is provided from below at three points on its circumference by 120 °. Exiting the top of each heat exchanger is provided at three points on its circumference with a shift in azimuth by 60 ° relative to the lower entry points. The invention improves the efficiency of the cooling system by increasing the service life of the helium tank, and improve the reliability of the cooling system, to simplify the structure and increase its rigidity.