AN ULTRAHIGH-VACUUM SCANNING TUNNELING MICROSCOPE WITH A NEW INCHWORM MECHANISM

An ultrahigh vacuum scanning tunneling microscope (STM) with a new piezo-driven inchworm for coarse positioning has been designed and constructed. The inchworm consists of five piezoelectric stacks and moves, being pressed from the side by a spring. This structure makes it durable to bakeout of the vacuum chamber. The tip and the sample set in the tunneling unit are exchangable without breaking vacuum. The STM chamber is attached to a conventional molecular beam epitaxy chamber equipped with surface analysis instruments without external vibration isolation. We have ascertained that the STM has an atomic-order resolution even under poor conditions, where much acoustic noise and mechanical vibration are produced by vacuum pumps and cooling water in the main chamber. © 1990, American Vacuum Society. All rights reserved.