Limits...
Properties of silicon dioxide layers with embedded metal nanocrystals produced by oxidation of Si:Me mixture.

Novikau A, Gaiduk P, Maksimova K, Zenkevich A - Nanoscale Res Lett (2011)

Bottom Line: A two-dimensional layers of metal (Me) nanocrystals embedded in SiO2 were produced by pulsed laser deposition of uniformly mixed Si:Me film followed by its furnace oxidation and rapid thermal annealing.It is found that Me segregation induced by Si:Me mixture oxidation results in the formation of a high density of Me and silicide nanocrystals in thin film SiO2 matrix.Strong evidence of oxidation temperature as well as impurity type effect on the charge storage in crystalline Me-nanodot layer is demonstrated by the hysteresis behavior of the high-frequency C-V curves.

View Article: PubMed Central - HTML - PubMed

Affiliation: Belarusian State University, 4 prosp, Nezavisimosti, 220030, Minsk, Belarus. andrei.novikau.by@gmail.com.

ABSTRACT
A two-dimensional layers of metal (Me) nanocrystals embedded in SiO2 were produced by pulsed laser deposition of uniformly mixed Si:Me film followed by its furnace oxidation and rapid thermal annealing. The kinetics of the film oxidation and the structural properties of the prepared samples were investigated by Rutherford backscattering spectrometry, and transmission electron microscopy, respectively. The electrical properties of the selected SiO2:Me nanocomposite films were evaluated by measuring C-V and I-V characteristics on a metal-oxide-semiconductor stack. It is found that Me segregation induced by Si:Me mixture oxidation results in the formation of a high density of Me and silicide nanocrystals in thin film SiO2 matrix. Strong evidence of oxidation temperature as well as impurity type effect on the charge storage in crystalline Me-nanodot layer is demonstrated by the hysteresis behavior of the high-frequency C-V curves.

No MeSH data available.


Related in: MedlinePlus

Transmission electron microscopy analysis from a Si:Pt sample, oxidized at T = 640°C for 5 h in dry O2: bright-field plain-view (a) and high resolution (b) TEM images. Crystalline PtSi NCs exhibit a dark contrast on the gray background of the SiO2 layer.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3211198&req=5

Figure 3: Transmission electron microscopy analysis from a Si:Pt sample, oxidized at T = 640°C for 5 h in dry O2: bright-field plain-view (a) and high resolution (b) TEM images. Crystalline PtSi NCs exhibit a dark contrast on the gray background of the SiO2 layer.

Mentions: The results of the plain-view TEM investigations (published elsewhere [14]) correlate well with the RBS data. Figure 3a clearly shows the well-separated clusters embedded in the SiO2 layer formed after thermal treatment. The average size and the areal density of the observed NCs were estimated to be from 10 to 20 nm and 2 × 1010 cm-2, respectively. To elucidate the structural properties of metal NCs, the HRTEM analysis was performed. The results for SiO2:NC-Pt are shown in Figure 3b. The bright-field TEM micrograph of the Si:Pt-alloyed sample oxidized at T = 640°C for 5 h reveals dark-gray clusters scattered on a light gray SiO2 background. Careful examination of the clusters structure performed using the direct resolution of crystallographic planes and selected area electron diffraction patterns analysis (not shown) evidences the formation of platinum monosilicide (PtSi) crystalline phase in NCs. In addition, unoxidized silicon islands were also identified. Similar results were also obtained for Si:Au samples although no evidence of Au silicide formation was found (not shown). A previous study [11] describing detailed in situ investigation by X-ray photoelectron spectroscopy of the Au chemical state evolution during the oxidation of the similarly produced Si:Au mixture indicated the formation of a metastable Au silicide during the room temperature deposition and its further decomposition to metallic Au upon oxidation.


Properties of silicon dioxide layers with embedded metal nanocrystals produced by oxidation of Si:Me mixture.

Novikau A, Gaiduk P, Maksimova K, Zenkevich A - Nanoscale Res Lett (2011)

Transmission electron microscopy analysis from a Si:Pt sample, oxidized at T = 640°C for 5 h in dry O2: bright-field plain-view (a) and high resolution (b) TEM images. Crystalline PtSi NCs exhibit a dark contrast on the gray background of the SiO2 layer.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3211198&req=5

Figure 3: Transmission electron microscopy analysis from a Si:Pt sample, oxidized at T = 640°C for 5 h in dry O2: bright-field plain-view (a) and high resolution (b) TEM images. Crystalline PtSi NCs exhibit a dark contrast on the gray background of the SiO2 layer.
Mentions: The results of the plain-view TEM investigations (published elsewhere [14]) correlate well with the RBS data. Figure 3a clearly shows the well-separated clusters embedded in the SiO2 layer formed after thermal treatment. The average size and the areal density of the observed NCs were estimated to be from 10 to 20 nm and 2 × 1010 cm-2, respectively. To elucidate the structural properties of metal NCs, the HRTEM analysis was performed. The results for SiO2:NC-Pt are shown in Figure 3b. The bright-field TEM micrograph of the Si:Pt-alloyed sample oxidized at T = 640°C for 5 h reveals dark-gray clusters scattered on a light gray SiO2 background. Careful examination of the clusters structure performed using the direct resolution of crystallographic planes and selected area electron diffraction patterns analysis (not shown) evidences the formation of platinum monosilicide (PtSi) crystalline phase in NCs. In addition, unoxidized silicon islands were also identified. Similar results were also obtained for Si:Au samples although no evidence of Au silicide formation was found (not shown). A previous study [11] describing detailed in situ investigation by X-ray photoelectron spectroscopy of the Au chemical state evolution during the oxidation of the similarly produced Si:Au mixture indicated the formation of a metastable Au silicide during the room temperature deposition and its further decomposition to metallic Au upon oxidation.

Bottom Line: A two-dimensional layers of metal (Me) nanocrystals embedded in SiO2 were produced by pulsed laser deposition of uniformly mixed Si:Me film followed by its furnace oxidation and rapid thermal annealing.It is found that Me segregation induced by Si:Me mixture oxidation results in the formation of a high density of Me and silicide nanocrystals in thin film SiO2 matrix.Strong evidence of oxidation temperature as well as impurity type effect on the charge storage in crystalline Me-nanodot layer is demonstrated by the hysteresis behavior of the high-frequency C-V curves.

View Article: PubMed Central - HTML - PubMed

Affiliation: Belarusian State University, 4 prosp, Nezavisimosti, 220030, Minsk, Belarus. andrei.novikau.by@gmail.com.

ABSTRACT
A two-dimensional layers of metal (Me) nanocrystals embedded in SiO2 were produced by pulsed laser deposition of uniformly mixed Si:Me film followed by its furnace oxidation and rapid thermal annealing. The kinetics of the film oxidation and the structural properties of the prepared samples were investigated by Rutherford backscattering spectrometry, and transmission electron microscopy, respectively. The electrical properties of the selected SiO2:Me nanocomposite films were evaluated by measuring C-V and I-V characteristics on a metal-oxide-semiconductor stack. It is found that Me segregation induced by Si:Me mixture oxidation results in the formation of a high density of Me and silicide nanocrystals in thin film SiO2 matrix. Strong evidence of oxidation temperature as well as impurity type effect on the charge storage in crystalline Me-nanodot layer is demonstrated by the hysteresis behavior of the high-frequency C-V curves.

No MeSH data available.


Related in: MedlinePlus