Doping-density dependence of scanning tunneling spectroscopy on lightly doped silicon

Abstract

The doping-density dependence of scanning tunneling spectroscopy on lightly doped hydrogen-terminated Si(100) (resistivities in the range of 0.2–12 Ω cm) was investigated in air with and without illumination. The observed doping-density dependence is consistent with a generation model in which the changes in the three-dimensional depletion region, induced by a scanning tunneling microscopy tip, contributes to changes in the concentration of thermally and/or photogenerated carriers in lightly doped samples. These results suggest that scanning tunneling spectroscopy can be used to image variations in dopant density in lightly doped samples.

A reverse bias, tip-insulator-semiconductor tunnel diode model accounting for the delineation of a p/p+ junction using scanning tunneling microscopy

“…18 Recently, experiments carried out on lightly doped silicon in our laboratories have demonstrated a doping density dependence of STS related to the generation process. 4 As an extension of our earlier work, in this article a tunnelinggeneration-avalanche model, associated with a lateral field effects, is proposed to predict the reverse bias I -V behavior of the Pt-Ir/air/p-Si tunnel junctions. The data herein are in agreement with the model and support the model's prediction that under appropriate conditions, p/p ϩ junctions ͑15 ⍀ cm/0.01 ⍀ cm͒, can be delineated using current imaging tunneling spectroscopy ͑CITS͒.…”

“…1 Once a MIS tunnel diode is formed, it is possible to characterize properties that influence device performance such as interfacial states and/or impurity distributions using reverse bias current-voltage (I -V) characteristics. [2][3][4] As a result, it is critical to develop an understanding of the reverse bias I -V characteristics of MIS tunnel diodes.…”

Fabrication of nanostructures with high electrical conductivity on silicon surfaces using a laser-assisted scanning tunneling microscope

“…The application of LA-STM to surface nanostructuring which will ultimately be utilized in micro-or nanoelectronics industry involves the completely understanding their electronic properties, which can be characterized by scanning tunneling spectroscopy ͑STS͒. [22][23][24][25] In this study, the fabrication of nanostructures with high electrical conductivity, on p-type H-passivated silicon ͑110͒ surfaces using LA-STM, was investigated. Nanostructures ͑dots and lines͒ were fabricated.…”

Bias voltage influence on the shape of cobalt-silicide nanowires

“…STM tip induced gap states are excluded in the present study, since they occur under small sample bias voltages (,1 V) [12], while at higher bias voltages the current between tip and sample is dominated by the tunneling process between the tip and the conduction band and therefore the current depends exponentially on the tipsample distance [13]. The use of Pt-Ir tips which is a high work function material (<5.5 eV) can lead also to pinning of the Fermi level close to the edge of the valence band, and it prohibits any spectral shifts arising from tip induced band bending due to formation of an inversion layer in n-type Si [14].…”

“…This development will be essential for scientific progress in many areas of Physics, Materials Science, Chemistry, Biology, etc. [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. These techniques will form enabling technologies for applications such as nanoelectronics, molecular electronics, microoptical components, nanoelectromechanical systems, catalysis, etc.…”