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A set of TiOxNy films was deposited by reactive RF magnetron sputtering varying the nitrogen partial pressure in a Ar/N2 gaseous mixture. Utilizing these films as gate dielectric layer MOS capacitors were fabricated and characterized. The TiOxNy films were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Rutherford Backscattering (RBS), optical absorption, and High Resolution Transmission Electron Microscopy (HRTEM). Capacitance-voltage (1MHz) and current-voltage measurements were used to obtain the effective dielectric constant, the effective oxide thickness (EOT), the leakage current density, and the interface quality. MOS capacitors results show that the TiOxNy films present a dielectric constant varying from 28 to 80, good interface quality with silicon, and a leakage current density of approximately 0.25 mA/cm2 for VG = -1V, which is acceptable for high performance logic circuits and low power circuits fabrication. The leakage current density is reduced in 3 orders of magnitude with an increase in nitrogen concentration.

A set of MOS capacitors with TiOxNy films as gate dielectric layer was fabricated and characterized. The TiOxNy films were deposited by reactive r.f. magnetron sputtering varying the nitrogen and oxygen partial pressure in a Ar/N2/O2 gaseous mixture. The TiOxNy films were characterized by, Rutherford Backscattering (RBS), X-ray absorption near edge spectroscopy (XANES) in oxygen K-edge (O-K), optical absorption and High Resolution Transmission Electron Microscopy (HRTEM). Capacitance-voltage (1MHz) and current-voltage measurements were performed to obtain the effective dielectric constant, the effective oxide thickness (EOT), the leakage current density, and the interface quality. MOS capacitors results show that the TiOxNyfilms dielectric constant varies from 28 to 80, present a good interface quality with silicon, and the leakage current density values are in the order of 0.25 mA/cm2 for VG = –2V, which is acceptable for high performance logic circuits and low power circuits fabrication. The leakage current density is reduced in 2 orders of magnitude for increasing nitrogen concentration (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Metal oxide semiconductor (MOS) capacitors with titanium oxide (TiOx) dielectric layer, deposited with different oxygen partial pressure (30, 35 and 40%) and annealed at 550, 750 and 1000 °C, were fabricated and characterized. Capacitance–voltage and current–voltage measurements were utilized to obtain, the effective dielectric constant, effective oxide thickness, leakage current density and interface quality. The obtained TiOx films present a dielectric constant varying from 40 to 170 and a leakage current density, for a gate voltage of − 1 V, as low as 1 nA/cm2 for some of the structures, acceptable for MOS fabrication, indicating that this material is a viable high dielectric constant substitute for current ultra thin dielectric layers.

MOS capacitors with TiO2 and TiO2/SiO2 dielectric layer were fabricated and characterized. TiO2 films where physical characterized by Rutherford Backscattering, Fourier Transform Infrared Spectroscopy and Elipsometry measurements. Capacitance-voltage (1MHz) and current-voltage measurements were utilized to obtain, the effective dielectric constant, effective oxide thickness (EOT), leakage current density and interface quality. The results show that the obtained TiO2 films present a dielectric constant of approximately 40, a good interface quality with silicon and a leakage current density, of 70 mA/cm2 for VG = 1V, acceptable for high performance logic circuits and low power circuits fabrication, indicating that this material is a viable substitute for current dielectric layers in order to prevent tunneling currents. The results for SiO2 (6nm) /TiO2(58nm) layer show a reduction of 3 orders of magnitude in leakage current density and an effec tive dielectric constant of 20, also viable to substitute the usual dielectric material in CMOS fabrication.

MOS capacitors with TiO2 deposited with different O2 partial pressure (30,35 and 40%) and annealed at 550, 750 and 1000oC were fabricated and characterized. Rutherford Backscattering, Fourier Transform Infrared Spectroscopy and Elipsometry measurements were performed to characterize the TiO2 films. Capacitance-voltage (1MHz) and current-voltage measurements were utilized to obtain: the effective dielectric constant, the effective oxide thickness (EOT), the leakage current density (J) and the interface quality. The results show that the obtained TiO2 films present a dielectric constant varying from 40 to 170 and a leakage current density, for gate voltage (VG) of -1V, attaining values as low as 1 nA/cm2, appropriated for CMOS circuits fabrication, indicating that this material is a feasible substitute for current dielectric layers in order to prevent tunneling currents.

In this work metal/oxide/semiconductor (MOS) capacitors with different nitrogen content SiO"xN"y gate dielectric are fabricated and characterized. The dielectric films are deposited by the plasma enhanced chemical vapor deposition technique from N"2, N"2O and SiH"4 gaseous mixtures at low temperatures. The MOS capacitors were characterized by low and high frequency capacitance (C-V) measurements, from where the interface state density (D"i"t), the effective charge density (N"e"f"f) and the dielectric constant (k) were extracted. The results show a dielectric constant varying linearly in function of the films nitrogen concentration, from a value of 3.9, corresponding to SiO"2 to 7.2, corresponding to Si"3N"4. We observed a variation of D"i"t in function of the films nitrogen concentration, the smallest obtained value corresponding to the Si"3N"4 film (~1x10^1^1 cm^-^2eV^-^1), however this film presents higher leakage current density than others. In order to optimize both parameters a double dielectric layer is proposed, a first layer of Si"3N"4 film, which presents the highest dielectric constant and best interface properties, and a second layer of SiO"xN"y with high nitrogen concentration, in order to maintain the equivalent dielectric constant high but minimizing the leakage current problems.

In this work metal/oxide/silicon (MOS) capacitors using SiOxNy and SiO2 films with different nitrogen concentrations as gate dielectrics were deposited by the plasma-enhanced chemical vapor deposition (PECVD) technique, fabricated and characterized. These films were obtained through the variation of the N2O/SiH4 flow ratio (R) at low temperatures (∼320 °C). The refractive index results show that by varying the N2O/SiH4 flow ratio it is possible to obtain a precise control of this parameter in the 1.46–1.57 range. From the low- and high-frequency C–V curves, the interface state density (Dit), the effective charge density (Nss), dielectric constant (k), among others were extracted. Optimized properties were found for the capacitor with a low nitrogen concentration (∼8%) SiOxNy gate dielectric.

The development of high sensitive miniaturized sensors is of special importance for “Lab on a Chip” and biosensors development [1]. In this context and due to its n-type semiconductor character and its high chemical stability, TiO 2 thin films have been proposed for application as pH and H sensors [2]. Even more, taking advantage of their high specific surface, TiO 2 nanotubes have been also considered as a natural candidate for application in pH detection [3].

Metal oxide-semiconductor capacitors with TiOx deposited with different O2 partial pressures (30%, 35%, and 40%) and annealed at 550, 750, and 1000°C were fabricated and characterized. Fourier transform infrared, x-ray near edge spectroscopy, and elipsometry measurements were performed to characterize the TiOx films. TiOxNy films were also obtained by adding nitrogen to the gaseous mixture and physical results were presented. Capacitance-voltage (1MHz) and current-voltage measurements were utilized to obtain the effective dielectric constant, effective oxide thickness, leakage current density, and interface quality. The results show that the obtained TiOx films present a dielectric constant varying from 40 to 170 and a leakage current density (for VG=−1V, for some structures as low as 1nA∕cm2, acceptable for complementary metal oxide semiconductor circuits fabrication), indicating that this material is a viable, in terms of leakage current density, highk substitute for current ultrathin dielectric layers.

In this paper the geometrical theory of pulse distortion and energy launching into multimode optical fibres is generalized when skew rays are taken into account.

MOS capacitors with TiO2 and TiO2/SiO2 dielectric layer were fabricated and characterized. TiO2 films where physical characterized by Rutherford Backscattering, Fourier TransformInfrared Spectroscopy and Elipsometry measurements. Capacitance-voltage (1MHz) and current voltage measurements were utilized to obtain, the effective dielectric constant, effective oxide thickness (EOT), leakage current density and interface quality. The results show that the obtained TiO2 films present a dielectric constant of approximately 40, a good interface quality with silicon and a leakage current density, of 70 mA/cm2 for VG = 1V, acceptable for high performance logic circuits and low power circuits fabrication, indicating that this material is a viable substitute for current dielectric layers in order to prevent tunneling currents.