Frequency Dependence of C-V Characteristics of MOS Capacitors Containing Nanosized High-κ Ta2O5 Dielectrics
Capacitance of metal–insulator–Si structures containing high permittivity dielectric exhibits complicated behaviour when voltage and frequency dependencies are studied. From our study on metal (Al, Au, W)–Ta2O5/SiO2–Si structures, we identify serial C-R measurement mode to be more convenient for use...
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| Format: | Article |
| Language: | English |
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Wiley
2017-01-01
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| Series: | Advances in Materials Science and Engineering |
| Online Access: | http://dx.doi.org/10.1155/2017/9745934 |
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| author | Nenad Novkovski Elena Atanassova |
| author_facet | Nenad Novkovski Elena Atanassova |
| author_sort | Nenad Novkovski |
| collection | DOAJ |
| description | Capacitance of metal–insulator–Si structures containing high permittivity dielectric exhibits complicated behaviour when voltage and frequency dependencies are studied. From our study on metal (Al, Au, W)–Ta2O5/SiO2–Si structures, we identify serial C-R measurement mode to be more convenient for use than the parallel one usually used in characterization of similar structures. Strong frequency dependence that is not due to real variations in the dielectric permittivity of the layers is observed. Very high capacitance at low frequencies is due to the leakage in Ta2O5 layer. We found that the above observation is mainly due to different leakage current mechanisms in the two different layers composing the stack. The effect is highly dependent on the applied voltage, since the leakage currents are strongly nonlinear functions of the electric field in the layers. Additionally, at low frequencies, transition currents influence the measured value of the capacitance. From the capacitance measurements several parameters are extracted, such as capacitance in accumulation, effective dielectric constant, and oxide charges. Extracting parameters of the studied structures by standard methods in the case of high-κ/interfacial layer stacks can lead to substantial errors. Some cases demonstrating these deficiencies of the methods are presented and solutions for obtaining better results are proposed. |
| format | Article |
| id | doaj-art-851646267e6f47b8ad3ef5059879f7e4 |
| institution | Kabale University |
| issn | 1687-8434 1687-8442 |
| language | English |
| publishDate | 2017-01-01 |
| publisher | Wiley |
| record_format | Article |
| series | Advances in Materials Science and Engineering |
| spelling | doaj-art-851646267e6f47b8ad3ef5059879f7e42025-02-03T01:04:55ZengWileyAdvances in Materials Science and Engineering1687-84341687-84422017-01-01201710.1155/2017/97459349745934Frequency Dependence of C-V Characteristics of MOS Capacitors Containing Nanosized High-κ Ta2O5 DielectricsNenad Novkovski0Elena Atanassova1Institute of Physics, Faculty of Natural Sciences and Mathematics, University “Ss. Cyril and Methodius”, Arhimedova 3, 1000 Skopje, MacedoniaInstitute of Solid State Physics, Bulgarian Academy of Sciences, 72 Tzarigradsko Chaussee Blvd., 1784 Sofia, BulgariaCapacitance of metal–insulator–Si structures containing high permittivity dielectric exhibits complicated behaviour when voltage and frequency dependencies are studied. From our study on metal (Al, Au, W)–Ta2O5/SiO2–Si structures, we identify serial C-R measurement mode to be more convenient for use than the parallel one usually used in characterization of similar structures. Strong frequency dependence that is not due to real variations in the dielectric permittivity of the layers is observed. Very high capacitance at low frequencies is due to the leakage in Ta2O5 layer. We found that the above observation is mainly due to different leakage current mechanisms in the two different layers composing the stack. The effect is highly dependent on the applied voltage, since the leakage currents are strongly nonlinear functions of the electric field in the layers. Additionally, at low frequencies, transition currents influence the measured value of the capacitance. From the capacitance measurements several parameters are extracted, such as capacitance in accumulation, effective dielectric constant, and oxide charges. Extracting parameters of the studied structures by standard methods in the case of high-κ/interfacial layer stacks can lead to substantial errors. Some cases demonstrating these deficiencies of the methods are presented and solutions for obtaining better results are proposed.http://dx.doi.org/10.1155/2017/9745934 |
| spellingShingle | Nenad Novkovski Elena Atanassova Frequency Dependence of C-V Characteristics of MOS Capacitors Containing Nanosized High-κ Ta2O5 Dielectrics Advances in Materials Science and Engineering |
| title | Frequency Dependence of C-V Characteristics of MOS Capacitors Containing Nanosized High-κ Ta2O5 Dielectrics |
| title_full | Frequency Dependence of C-V Characteristics of MOS Capacitors Containing Nanosized High-κ Ta2O5 Dielectrics |
| title_fullStr | Frequency Dependence of C-V Characteristics of MOS Capacitors Containing Nanosized High-κ Ta2O5 Dielectrics |
| title_full_unstemmed | Frequency Dependence of C-V Characteristics of MOS Capacitors Containing Nanosized High-κ Ta2O5 Dielectrics |
| title_short | Frequency Dependence of C-V Characteristics of MOS Capacitors Containing Nanosized High-κ Ta2O5 Dielectrics |
| title_sort | frequency dependence of c v characteristics of mos capacitors containing nanosized high κ ta2o5 dielectrics |
| url | http://dx.doi.org/10.1155/2017/9745934 |
| work_keys_str_mv | AT nenadnovkovski frequencydependenceofcvcharacteristicsofmoscapacitorscontainingnanosizedhighkta2o5dielectrics AT elenaatanassova frequencydependenceofcvcharacteristicsofmoscapacitorscontainingnanosizedhighkta2o5dielectrics |