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Comparative study between silicon-rich oxide films obtained by LPCVD and PECVD

MARIANO ACEVES MIJARES (2007)

A comparative study of compositional and optical properties of silicon-rich oxide (SRO) films deposited by low-pressure chemical

vapor deposition (LPCVD) and plasma-enhanced chemical vapor deposition (PECVD) is presented. Infrared spectra revealed the

presence of hydrogen bonded to silicon atoms in the SRO–PECVD films, whereas in SRO–LPCVD films the IR spectra looked like the

stoichiometric thermal silicon oxide. Moreover, X-ray photoelectron spectroscopy (XPS) studies showed that the SRO–PECVD films

contain a higher content of nitrogen than SRO–LPCVD films. In spite of differences, the SRO films obtained by both methods show a

strong room-temperature photoluminescence (PL). However, the highest PL intensity was emitted by SRO films obtained by LPCVD.

Article

Silicon rich oxide Infrared spectroscopy XPS Photoluminescence CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ELECTRÓNICA

OPTICAL CHARACTERIZATION OF SILICON RICH OXIDE FILMS

ALFREDO MORALES SANCHEZ MARIANO ACEVES MIJARES (2006)

SRO films obtained by LPCVD have shown a strong visible photoluminescence (PL) after annealed

at 1100°C. Since these materials are robust and efficient, they have shown having potential applications in

optoelectronics. Structural and optical studies on these materials were carried out. The results suggest that the

emission can be related to defects surrounding the Silicon c1usters and nanocrystals.

Conference proceedings

Silicon Rich Oxide BIOLOGÍA Y QUÍMICA QUÍMICA QUÍMICA FÍSICA OTRAS

Fabrication and characterization of coplanar waveguides on silicon using a combination of SiO2 and SRO20

REBECA LEAL ROMERO IGNACIO ENRIQUE ZALDIVAR HUERTA MARIA DEL CARMEN MAYA SANCHEZ MARIANO ACEVES MIJARES J. APOLINAR REYNOSO HERNANDEZ (2008)

In this work, the use of silicon rich oxide (SRO) and chemical vapor deposition SiO2 double layers as passivation films of coplanar waveguides (CPW) on high resistivity silicon (HR-Si) with an N+ backside is studied. The microwave performance of the fabricated CPWs is evaluated by computing the attenuation loss of the devices in the 0.045–50 GHz frequency range. Experimental results show that the N+ layer can be used without affecting CPW performance. Also, using a combined dielectric layer (SRO20/SiO2), the attenuation losses are reduced compared to single dielectric layers.

Article

Attenuation constant Coplanar waveguide (CPW) Dielectric constant Silicon rich oxide (SRO) Traveling wave CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ELECTRÓNICA

On the photoluminescence of multilayer arrays of silicon rich oxide with high silicon content prepared by low pressure chemical vapor deposition

ENRIQUE QUIROGA GONZALEZ MARIANO ACEVES MIJARES ZHENRUI YU ROSA ELVIA LOPEZ ESTOPIER KARIM MONFIL LEYVA (2011)

The photoluminescence emission of multilayer structures composed of layers of silicon rich oxide with high silicon content and layers of silicon rich oxide with low silicon content obtained by low pressure chemical vapor deposition is here presented. Different parameters for the preparation of the multilayers have been varied such as the Si concentration and the thicknesses of the layers. Additionally, the samples were oxidized at different temperatures. For all samples the photoluminescence seems to have the same origin: defects in the oxide matrix and defects at the interfaces between the Si nanocrystals. The structural and compositional properties of the multilayer structures are discussed.

Article

Multilayers Silicon rich oxide Nanoparticles Photoluminescence Low-pressure chemical vapor deposition Transmission electron microscopy CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ELECTRÓNICA ELECTRÓNICA

The deposition and control of self assembled silicon nano islands on crystalline silicon

ZHENRUI YU MARIANO ACEVES MIJARES (2008)

The formation of nano sized Si structures during the annealing of silicon rich oxide (SRO) films was investigated. These films were synthesized by low pressure chemical vapor deposition (LPCVD) and used as precursors, a post-deposition thermal annealing leads to the formation of Si nano crystals in the SiO2 matrix and Si nano islands (Si nI) at c-Si/SRO interface. The influences of the excess Si concentration, the incorporation of N in the SRO precursors, and the presence of a Si concentration gradient on the Si nI formation were studied. Additionally the influence of pre-deposition substrate surface treatments on the island formation was investigated. Therefore, the substrate surface was mechanical scratched, producing high density of net-like scratches on the surface. Scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM) were used to characterize the synthesized nano islands. Results show that above mentioned parameters have significant influences on the Si nIs. High density nanosized Si islands can epitaxially grow from the c-Si substrate. The reported method is very simple and completely compatible with Si integrated circuit technology.

Article

Si nano islands Self assembly Epitaxial growth Silicon-rich oxide Photoluminescence CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ELECTRÓNICA

Fabricación de heterouniones con un Óxido Conductor Transparente (TCO) y Óxido de Silicio fuera de estequiometría (SRO)

MARCO POLO GONZÁLEZ ARROYO (2015)

En este trabajo se presenta el proceso de fabricación y caracterización de una heterounión obtenida al depositar una película de un óxido conductor transparente (TCO) sobre una película de óxido de silicio rico en silicio (SRO). Como TCO se propuso usar una película de óxido de indio impurificado con zinc (IZO) u óxido de zinc impurificado con aluminio (AZO). Como primera etapa, se presentan los resultados de la caracterización de películas IZO y AZO depositadas sobre sustratos de vidrio Corning mediante la técnica de depósito RF Magnetrón Sputtering. El depósito de películas IZO se realizó usando un blanco cerámico de IZO (In2O3:ZnO, 90:10 wt% de Kurt J. Lesker) en ambiente de argón a temperatura ambiente. La caracterización eléctrica, óptica, estructural y morfológica de estas películas se realizó mediante mediciones de 4 Puntas, Efecto Hall, Transmitancia, Fotoluminiscencia, Difracción de Rayos X (XRD) y Microscopio de Fuerza Atómica (AFM). El estudio de las películas se realizó en función de los parámetros de depósito como potencia, presión, tiempo, flujo de oxígeno durante el depósito y tratamientos térmicos post-depósito.

Master thesis

Transparent conducting oxides Silicon rich oxide Heterojunctions CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ELECTRÓNICA

Compositional and structural characterization of silicon nanoparticles embedded in silicon rich oxide

JOSE ALBERTO LUNA LOPEZ MARIANO ACEVES MIJARES OLEKSANDR MALIK JORGE EDUARDO RICKARDS CAMPBELL (2007)

Silicon Rich Oxide (SRO) is a dielectric material that contains Si nanoparticles, thus showing novel physical characteristics which permits

its use in optoelectronic devices. In this work, the composition and structure at the surface, volume and Si/SRO interface of the SRO films deposited on c-Si substrates were studied. Different techniques, such as Atomic Force Microscopy (AFM), High Resolution Transmission Electronic Microscopy (HRTEM), Rutherford Backscattering Spectrometry (RBS) and X-ray Photoelectron Spectroscopy (XPS) were used in the study. XPS and RBS reveal that the composition of the films varied with respect to the gas flow ratio. These results allow us to correlate the compositional and structural [as size of the grains (roughness), nc-Si size and different oxidation states of Si] changes of the surface, volume and interface from the SRO films with the flow ratio (Ro) used during the deposition process and with the high temperature annealing time.

Article

Silicon rich oxide AFM HRTEM Nanocrystals Surface roughness RBS XPS CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ELECTRÓNICA

Surface and Interface Structure of silicon Rich Oxide Films

JORGE ALBERTO LUNA LOPEZ MARIANO ACEVES MIJARES (2006)

Si nanocrystals are promising materials which can be used for optical sensor, memory devices and future optoelectronics devices. In this work we study the morphology surface and interface of silicon rich oxide (SRO) films with different nanocrystals (nc-Si) embedded in a thin Sio2 matrix (Silicon excess).

Conference proceedings

Silicon Rich Oxide Nanocrystals RBS BIOLOGÍA Y QUÍMICA QUÍMICA QUÍMICA FÍSICA OTRAS

MOS-like electroluminisescent devices using silicon-rich oxide obtained by LPCVD

MARIANO ACEVES MIJARES (2009)

silicon Rich Oxide (SRO) is a multiphase material composed by SiO2, Si and SiOx(0<X<2) SRO characteristics include the photo and cathode emission of visible light. Lastly, big efforts have been devoted to obtain a controllable emission using electroluminescence, but keeping its compatibility with silicon Ic's fabrication technology.

Conference proceedings

Silicon rich oxide BIOLOGÍA Y QUÍMICA QUÍMICA QUÍMICA FÍSICA OTRAS

FTIR and photoluminescence of annealed silicon rich oxide films

MARIANO ACEVES MIJARES ALFREDO MORALES SANCHEZ (2009)

In order to have optoelectronic function integrated in a single chip, it is very important to obtain a silicon compatible material with an optimal Photoluminescence (PL) response. The Silicon Rich Oxide (SRO) has shown intense PL and is also compatible with silicon technology. In this work, the composition and optical properties of the SRO films are studied using null Ellipsometry, Fourier Transformed Infrared spectroscopy (FTIR), and Photoluminescence (PL). The SRO films were annealed at high temperature during different times. The IR absorption spectra show the presence of three characteristics Si-O-Si vibrations modes in SiO2. However, changes in their intensity and position were observed when annealing time and silicon excess were varied. These changes are directly related with structural variation in the SRO films. PL spectra show a considerable emission in the range 650 to 850 nm that varies with different thermal treatment times.

Article

Silicon Rich Oxide (SRO) Silicon nanoparticles Refractive index Photoluminescence FTIR CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ELECTRÓNICA