Short-range electrostatic interactions in atomic-resolution scanning force microscopy on theSi(111)7×7surface

Scanned Probe Microscopy first received widespread recognition in the form of scanning tunneling microscopy (STM) images clearly showing atomic resolution of the Si 111 surface in the characteristic 7×7 surface reconstruction. For this sample, STM imaging under carefully controlled ultrahigh vacuum conditions reveals the clear image of each atom position within the surface unit cell with excellent contrast and clearly atomic resolution. Over the past few years, versions of scanning force microscopy (commonly referred to as atomic force microscopy or AFM) have become much more widespread than STM. A very common, and very difficult question, is: What is the resolution of AFM? The simple answer is that SPM in general, and STM and AFM in particular, routinely obtain sub-angstrom resolution—in the z axis, or the sample height direction. This high resolution capability is easily demonstrated by scanning a cleaved crystal of known lattice spacing and observing single and multiple atomic steps.

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Dynamic scanning force microscopy at low temperatures on a noble-gas crystal: Atomic resolution on the xenon(111) surface

EPL (Europhysics Letters) ◽

10.1209/epl/i1999-00477-3 ◽

1999 ◽

Vol 48 (3) ◽

pp. 276-279 ◽

Cited By ~ 47

Author(s):

W Allers ◽

A Schwarz ◽

U. D Schwarz ◽

R Wiesendanger

Keyword(s):

Low Temperatures ◽

Noble Gas ◽

Scanning Force Microscopy ◽

Atomic Resolution ◽

Force Microscopy ◽

Scanning Force ◽

Dynamic Scanning

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Scanned tip measurement of deep vertical facets on a flat surface: Measuring roughness on gaas laser waveguide mirrors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100148496 ◽

1993 ◽

Vol 51 ◽

pp. 532-533

Author(s):

Chang Shen ◽

Phil Fraundorf ◽

Robert W. Harrick

Keyword(s):

Integrated Circuits ◽

Flat Surface ◽

Scanning Force Microscopy ◽

Scanning Tunneling ◽

Tunneling Microscopy ◽

Force Microscopy ◽

Optoelectronic Integrated Circuits ◽

Laser Waveguide ◽

Scanning Force ◽

Gaas Laser

Monolithic integration of optoelectronic integrated circuits (OEIC) requires high quantity etched laser facets which prevent the developing of more-highly-integrated OEIC's. The causes of facet roughness are not well understood, and improvement of facet quality is hampered by the difficulty in measuring the surface roughness. There are several approaches to examining facet roughness qualitatively, such as scanning force microscopy (SFM), scanning tunneling microscopy (STM) and scanning electron microscopy (SEM). The challenge here is to allow more straightforward monitoring of deep vertical etched facets, without the need to cleave out test samples. In this presentation, we show air based STM and SFM images of vertical dry-etched laser facets, and discuss the image acquisition and roughness measurement processes. Our technique does not require precision cleaving. We use a traditional tip instead of the T shape tip used elsewhere to preventing “shower curtain” profiling of the sidewall. We tilt the sample about 30 to 50 degrees to avoid the curtain effect.

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