AVS 47th International Symposium
    Processing at the Nanoscale/NANO 6 Wednesday Sessions
       Session NS+NANO6+MC-WeM

Paper NS+NANO6+MC-WeM7
A Liquid Helium Temperature Ultrahigh Vacuum Dual-tip Scanning Tunneling Microscope

Wednesday, October 4, 2000, 10:20 am, Room 302

Session: Nanomechanical and Interface Measurements
Presenter: H. Okamoto, Rowland Institute for Science
Authors: H. Okamoto, Rowland Institute for Science
D. Chen, Rowland Institute for Science
Correspondent: Click to Email
A dual-tip scanning tunneling microscope (D-STM) is a powerful instrument for investigating dissipative, diffusive, or ballistic transport phenomena of electrons in nanoscale structures.@footnote 1@ Here we present an ultrahigh vacuum compatible D-STM system working at liquid helium temperature for these new potential applications. Coarse positioning system consists of five rigid and compact inertial steppers, which has mechanical resonant frequency of ~900 Hz after integration. Each stepper has embedded capacitive position sensors with sub-micron resolution. An efficient new method, which we call tri-plane method, is used to navigate the two tips to proximity. The whole D-STM system is installed in a home-made vapor-cooled helium cryostat with a very low evaporation rate of 1.25 liter/day without liquid nitrogen radiation shield. @FootnoteText@ @footnote 1@Q. Niu et al., Phys. Rev. B 51 5502 (1995).