hide
Free keywords:
Biological specimen preparation; Carbon; Electron beam deposition; Ion beam effects; Scanning tunnelling microscopy; Substrates; Surface treatment; Biophysical instrumentation and techniques [A8780]; Scanning probe microscopy determinations of structures [A6116P]
Abstract:
A method is described for reducing the surface corrugation of amorphous carbon films prepared on glass or mica by electron beam evaporation. Normally, a film with a thickness of 10 nm exhibits a peak-to-valley corrugation of about 1.5 nm within an area of 200 nm/sup 2/ in STM measurements. After rotary ion-milling of the film surface in vacuum by an argon beam at low angle of incidence, the corrugation measured by STM is reduced to a value of 0.8 to 1 nm on an area of the same size. Such films were tested as substrates for metal-coated type-I collagen, a filamentous biomolecule only 1.4 nm in diameter. In STM images this molecule was much easier to identify on ion-milled substrates than it was on standard carbon or platinum-carbon film substrates. (11 References).
