Application to biology and technology of the scanning tunneling microscope operated in air at ambient pressure
by A. M. Baro, R. Miranda, J. L. Carrascosa
We have investigated the operation of the scanning tunneling microscope (STM) in air at atmospheric pressure, thus permitting the imaging of samples without the need for subjecting them to a vacuum environment. Clearly, this may be of practical importance for many types of samples having biological and technological interest. Imaging of biological samples has been found to be possible after deposition onto a flat structureless conducting substrate (highly oriented pyrolytic graphite). Three-dimensional profiles of structures derived from the virus designated as bacteriophage ɸ29 could thus be obtained. Other profiles have been obtained which indicate applicability to surfaces of technological interest: for example, in the measurement of the surface roughness of industrial components with increased precision, suggesting use of the STM as a new standard instrument for that purpose.