Hordiienko Y.
Professor, doc. of phys. and math. sci., Chief Researcher of the Department of
Microelectronics, Electronic Devices and Appliances, KNURE, Kharkiv, Ukraine
Levchenko A.
Postgraduate student of the Department of Microelectronics, Electronic Devices
and Appliances, KNURE, Kharkiv, Ukraine
THEORETICAL ASPECTS OF PHYSICAL IMAGES FORMATION IN
SCANNING MICROWAVE MICROSCOPY
Introduction. SMM is a product of the development of radio wave methods of
an electrodeless non-destructive method for controlling the electrophysical parameters
of various materials and a new area of probe nanotechnology, which can be called
"microwave nanodiagnostics of materials and objects."
It covers the high-resolution multi-parameter control of the spatial distribution
(tomography) of the electrophysical properties of objects and on its basis the
assessment of the functional capabilities of various nanotechnologies and
nanoconducts, etc.
To justify the foregoing, it suffices to point out that, unlike the AFM, which
basically shows the nanoprofile of the object's surface, the SMM image contains
information not only about the surface profile, but also nanoscale information on the
distribution profile of the permittivity and electrical conductivity (or tgδ on the
microwave) [1, 2]; photosensitivity [3], moisture content [4]; magnetic properties [5],
etc. Naturally, the necessary multi-parametrization of diagnostics is realized by
organizing an appropriate number of the extracted signals of the measurement
information and highlighting the contribution of each of them in the process of image
processing. In general, the study of the issues of restoring the physical nature of the
images of the parameters of the object under investigation using SMM is very relevant
[6].
In [1, 2], the first attempts were made to establish a two-parameter diagnostics
with SMM and to create the principles of the necessary theory. Theoretically, the task
of solving the inverse measurement problem exists only in the situation when the direct
problem is solved by purely approximate numerical methods [7]. For SMM, this is just
the characteristic.
Scanning Microwave Microscopy (SMM), by being a separate type of scanning
probe microscopy (SPM), allows us to measure the surface microrelief, spatial
distribution of specific resistivity, dielectric permittivity, to build the profilogram of
carrier distribution by depth, to estimate the lifetime and mobility of carriers in
contactless way by means of its principles. The diagnostics of semiconductors has its
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