Báo cáo hóa học: Properties of silicon dioxide layers with embedded metal nanocrystals produced by oxidation of Si: Me mixture

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Properties of silicon dioxide layers with embedded metal nanocrystals produced by oxidation of Si:Me mixture
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Báo cáo hóa học: " Properties of silicon dioxide layers with embedded metal nanocrystals produced by oxidation of Si:Me mixture"Novikau et al. Nanoscale Research Letters 2011, 6:148http://www.nanoscalereslett.com/content/6/1/148 NANO EXPRESS Open AccessProperties of silicon dioxide layers withembedded metal nanocrystals produced byoxidation of Si:Me mixtureAndrei Novikau1*, Peter Gaiduk1, Ksenia Maksimova2, Andrei Zenkevich2 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.Introduction Si or Ge NCs was reported in [4,6]. However, the implantation of Ge at the silicon-tunnel oxide interfaceDuring the last decade, much attention has been focused creates trap sites and results in the degradation of theon the investigation of semiconductor and metallic device performance [4]. The growth technique usingnanocrystals (NCs) or nanoclusters embedded in dielec- MBE deposition of 0.7-1 nm thick Ge layer followed bytric matrices. The interest is motivated by possible rapid thermal processing was implemented in [8,9]. Anapplications of such nanocomposite structures. Particu- alternative method for Ge NCs production [10] consistslarly, semiconductor or metal NCs embedded in SiO2 of the following steps: low pressure chemical vapordielectric layer of a metal-oxide-semiconductor field- deposition of thin Si-Ge layer, thermal wet or dry oxida-effect transistor may replace SiNx floating gate in con- tion, and thermal treatment in an inert ambient (reduc-ventional Flash memory devices, allowing for thinner tion). Recently, a method to form an ultrathininjection oxides, and subsequently, smaller operating nanocomposite SiO2:NC-Me layers at room temperaturevoltages, longer retention time, and faster write/erasespeeds [1-3]. The performance of such memory struc- by combining the deposition of Si:Me mixed layer onture strongly depends on the characteristics of the NCs the pre-oxidized Si substrate and its further oxidation inarrays, such as their size, shape, spatial distribution, the glow discharge oxygen plasma was proposed [11].electronic band alignment. In this article, a similar approach was used to produce Several approaches have been recently tested for the thin SiO2 layers with an embedded layer of metal NCs.formation of NCs in dielectric layers. Among those, self- Au and Pt were chosen as metal components in Si:Meassembling of NCs in dielectric layers fabricated by the mixtures since both metals are believed to catalyze Silow-energy ion implantation and different deposition oxidation thus reducing the processing temperature,te ...