Comparison of scanning tunneling microscope-light emission and photoluminescence from porphyrin films using ultra-high vacuum scanning tunneling microscopy

AbstractThe electrical properties of single dangling bonds on the Si(100)2×1:H surface are investigated by ultra high vacuum scanning tunneling microscopy. On the N-type Si(100)2×1:H surface, single dangling bonds created by feedback controlled lithography and natural dangling bonds have a fixed negative charge. On the other hand, they are observed as neutral on the P-type Si(100)2×1:H surface. Current image tunneling spectroscopy is used to characterize both types of dangling bonds. The dangling bonds with fixed negative charge display a dramatic voltage dependence with Friedel oscillations observed in the empty state images. The neutral dangling bonds appear as protrusions in both the empty and filled state images.

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A Scanning Tunneling Microscopy Study: Si/SiO2 Interface Roughness Induced by Chemical Etching

MRS Proceedings ◽

10.1557/proc-838-o4.9 ◽

2004 ◽

Vol 838 ◽

Author(s):

Jixin Yu ◽

Lequn Liu ◽

Joseph W. Lyding

Keyword(s):

Scanning Tunneling Microscopy ◽

Chemical Etching ◽

High Vacuum ◽

Microscopy Study ◽

Interface Roughness ◽

Ultra High Vacuum ◽

Scanning Tunneling ◽

Tunneling Microscopy ◽

Channel Mobility ◽

Scanning Tunneling Microscopy Study

ABSTRACTThe Si/SiO2 interface roughness has received tremendous interest due to its relation to channel mobility degradation and dielectric reliability. We have used ultra-high vacuum scanning tunneling microscopy to directly examine the Si/SiO2 interface and study the roughening effect caused by chemical etching. The rms-roughness extracted quantitatively from the STM topography was found to be doubled from 0.111nm to 0.232nm by the normal NH4OH/H2O2 treatment, and further increased to 0.285nm for additional etching steps. It was also found that there were no regular single steps on the SiO2/Si(100) interface.

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Ultra High Vacuum Scanning Tunneling Microscopy Observation of Multilayer Step Structure on GaAs and AlAs Vicinal Surface Grown by Metalorganic Vapor Phase Epitaxy

MRS Proceedings ◽

10.1557/proc-448-95 ◽

1996 ◽

Vol 448 ◽

Cited By ~ 3

Author(s):

Jun-Ya Ishizaki ◽

Yasuhiko Ishizaki ◽

Takashi Fukui

Keyword(s):

Scanning Tunneling Microscopy ◽

High Vacuum ◽

Gaas Layer ◽

Layer Growth ◽

Ultra High Vacuum ◽

Scanning Tunneling ◽

Vicinal Surface ◽

Microscopy Observation ◽

Tunneling Microscopy ◽

Atomic Structures

AbstractWe observe the atomic structures at the multilayer step region on MOVPE-grown GaAs (001) vicinal surface using ultra high vacuum scanning tunneling microscopy (UHV-STM), and clarify that (4×2) or (4×3) like reconstruction units are dominant. Oxide free AlAs surfaces grown on GaAs vicinal surface are also successfully observed by UHV-STM. The reconstruction units at the multilayer step region on AlAs surface have the same units on GaAs vicinal surface. GaAs surface has the lack of dimmer rows on the terrace region just below the multilayer step region, while AlAs surface has dimmer rows even on the terrace just below the multilayer step region. GaAs layer growth leads tothe step bunching phenomenon and AlAs surface leads to the step debunching phenomenon.

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