In this dissertation, we investigate the possibility to use scanning microscopy such as scanning capacitance microscopy (SCM)
and scanning spreading resistance microscopy (SSRM) for the "atomistic" dopant profiling of semiconductor materials. For this purpose, we
first analyze the discrete effects of random dopant fluctuations (RDF) on SCM and SSRM measurements with nanoscale probes and show that
RDF significantly affects the differential capacitance and spreading resistance of the SCM and SSRM measurements if the dimension of the
probe is below 50 nm. Then, we develop a mathematical algorithm to compute the spatial coordinates of the ionized impurities in the
depletion region using a set of scanning microscopy measurements. The proposed numerical algorithm is then applied to extract the (x, y,
z) coordinates of ionized impurities in the depletion region in the case of a few semiconductor materials with different doping
configuration. The numerical algorithm developed to solve the above inverse problem is based on the evaluation of doping sensitivity
functions of the differential capacitance, which show how sensitive the differential capacitance is to doping variations at different
locations. To develop the numerical algorithm we first express the doping sensitivity functions in terms of the Gâteaux derivative of the
differential capacitance, use Riesz representation theorem, and then apply a gradient optimization approach to compute the locations of
the dopants. The algorithm is verified numerically using 2-D simulations, in which the C-V curves are measured at 3 different locations on
the surface of the semiconductor. Although the cases studied in this dissertation are much idealized and, in reality, the C-V measurements
are subject to noise and other experimental errors, it is shown that if the differential capacitance is measured precisely, SCM
measurements can be potentially used for the "atomistic" profiling of ionized impurities in doped semiconductors. / A Dissertation submitted to the Department of Electrical and Computer Engineering in partial
fulfillment of the Doctor of Philosophy. / Spring Semester 2016. / March 07, 2016. / Doping, Fluctuations, Ion Implantation, Nanoscale Devices, Scanning Probe Microscopy / Includes bibliographical references. / Petru Andrei, Professor Directing Dissertation; Mei Zhang, University Representative; Simon Foo,
Committee Member; Jianping Zheng, Committee Member.
| Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_360308 |
| Contributors | Aghaei Anvigh, Samira (authoraut), Andrei, Petru (professor directing dissertation), Zhang, Mei (university representative), Foo, Simon Y. (committee member), Zheng, Jianping P. (committee member), Florida State University (degree granting institution), FAMU-FSU College of Engineering (degree granting college), Department of Electrical and Computer Engineering (degree granting department) |
| Publisher | Florida State University |
| Source Sets | Florida State University |
| Language | English, English |
| Detected Language | English |
| Type | Text, text |
| Format | 1 online resource (102 pages), computer, application/pdf |
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