AN OPTICAL-DETECTION LOW-TEMPERATURE ATOMIC-FORCE MICROSCOPE AT AMBIENT PRESSURE FOR BIOLOGICAL-RESEARCH

A low temperature atomic force microscope, based on the optical lever detection method and operated in liquid nitrogen vapor at ambient pres sure, has been constructed. The experimental results show that atomic resolution images can be obtained on both mica and highly oriented pyr olytic graphite at temperatures down to 79 K with sufficient thermal s tability. In liquid nitrogen vapor, no surface contamination was obser ved after many hours of continuous operation, which demonstrates that such an approach is ideal for biological applications for its lower co st and easy maintenance.