MIS-type structures composed of silicon-rich oxide (SRO), thin films deposited by hot filament chemical vapor deposition (HFCVD), show interesting I-V and I-t properties under white light illumination and a response as photodetectors. From electrical measurements, it was found that at a reverse bias of −4 V, the illumination current increased by up to three orders of magnitude relative to the dark current, which was about 82 nA, while the photogenerated current reached a value of 25 μA. The reported MIS structure with SRO as the dielectric layer exhibited a hopping conduction mechanism, and an ohmic conduction mechanism was found with low voltage. I-t measurements confirmed the increased photogenerated current. Furthermore, the MIS structure, characterized by current-wavelength (I-λ) measurements, exhibited a maximum responsivity value at 254 mA/W, specific detectivity (D*) at 2.21 × 10¹¹ cm Hz^1/2 W⁻¹, and a noise equivalent power (NEP) of 49 pW at a wavelength of 535 nm. The structure exhibited good switching behavior, with rise and fall times between 120 and 150 ms, respectively. These rise and decay times explain the generation and recombination of charge carriers and the trapping and release of traps, respectively. These results make MIS-type structures useful as photodetectors in the 420 to 590 nm range.

In this work, hybrid structures formed by nanostructured layers, which contain materials, such as porous silicon (PSi), carbon nanotubes (CNTs), graphene oxide (GO), and silicon-rich oxide (SRO), were studied. The PSi layers were obtained by electrochemical etching over which CNTs and GO were deposited by spin coating. In addition, SRO layers, in which silicon nanocrystals are embedded, were obtained by hot filament chemical vapor deposition (HFCVD) technique. Photoluminescence (PL) spectra were obtained from the hybrid structures with which a comparative analysis was completed among different PL ones. The SRO layers were used to confine the CNTs and GO. The main purpose of making these hybrid structures is to modulate their PL response and obtain different emission energy regions in the PL response. It was found that the PL spectra of the CNTs/SRO and GO/SRO structures exhibit a shift towards high energies compared to those obtained from the PSi layers; likewise, the PSi/CNTs/SRO and PSi/GO/SRO structures show a similar behavior. To identify the different emission mechanisms originated by PSi, GO, CNTs, and SRO, the PL spectra were deconvolved. It was found that the Psi/CNTs/SRO and Psi/GO/SRO structures exhibit a PL shift in respect to the PSi layers, for this reason, the modulation of the PL emission of the structures makes these hybrid structures promising candidates to be applied in the field of photonic and electroluminescent devices.

In this work, electroluminescence in Metal-Insulator-Semiconductors (MIS) and Metal-Insulator-Metal (MIM)-type structures was studied. These structures were fabricated with single- and double-layer silicon-rich-oxide (SRO) films by means of Hot Filament Chemical Vapor Deposition (HFCVD), gold and indium tin oxide (ITO) were used on silicon and quartz substrates as a back and front contact, respectively. The thickness, refractive indices, and excess silicon of the SRO films were analyzed. The behavior of the MIS and MIM-type structures and the effects of the pristine current-voltage (I-V) curves with high and low conduction states are presented. The structures exhibit different conduction mechanisms as the Ohmic, Poole–Frenkel, Fowler–Nordheim, and Hopping that contribute to carrier transport in the SRO films. These conduction mechanisms are related to the electroluminescence spectra obtained from the MIS and MIM-like structures with SRO films. The electroluminescence present in these structures has shown bright dots in the low current of 36 uA with a voltage of −20 V to −50 V. However, when applied voltages greater than −67 V with 270 uA, a full area with uniform blue light emission is shown.

In this work, we conducted a comparative study of the optical and structural properties of Silicon Rich Oxide (SRO) films deposited by two chemical vapor deposition techniques: at Low Pressure (LPCVD) and activated by Hot Filament (HFCVD). SRO-LPCVD films were deposited at a silane and nitrous oxide pressures (R_0=P_(N_2 O)/P_(〖SiH〗_4 )) rate of R0=10 y R0=25. SRO-HFCVD films were deposited at a hydrogen pressure of 25 and 100 sccm, at a distance between source and substrate of 8 mm. To improve the optical properties, we have subjected the films obtained by both techniques to thermal treatments at high temperatures. The optical and structural characterizations that we used for comparison of the films were: Null Spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR) and Photoluminescence (FL), Scanning Electron Microscopy (SEM) and High-Resolution Transmission Electron Microscopy (HRTEM). The SEM microscopy corroborates the thicknesses of the SRO films obtained by Null Spectroscopy, likewise, the HRTEM microscopy corroborates the diameter size of the silicon nanocrystals (ncs-Si), which also were calculated theoretically with the band gap energy (Eg) obtained in the FL spectra. These characterizations show that either of the two techniques are excellent alternatives for obtaining SRO films with photoluminescent emission, which can be used for photodetector and electroluminescent devices.

En este trabajo se desarrolla el diseño conceptual de un horno horizontal de tubo de cuarzo que opera a altas temperaturas (mayores a 600 °C) aplicando una metodología híbrida de ingeniería concurrente. Se incorpora la teoría de resolución de problemas inventivos TRIZ, por su acrónimo en ruso, como herramienta para generar ideas y conceptualizar los diseños. En esta etapa se desarrollan tres diseños que incluyen dos tipos de aislamiento, zirconia y un aislante con 42% de alúmina que pueden operar en rangos de temperatura de 1300°C a 1000°C y de 1000°C a 60°C, respectivamente. En la etapa de selección de diseño se aplica la matriz de Pugh, la solución seleccionada se evalúa mediante una simulación térmica a temperaturas de 800°C, 1000°C y 1200°C, los resultados de la simulación muestran temperaturas seguras de operación en las caras de la carcasa (<80 °C), los perfiles térmicos muestran que la temperatura es homogénea a lo largo del diámetro del tubo y de aproximadamente 100mm a lo largo del tubo.

This work presents the manufacturing and characterization process of two types of transparent conductive oxide (TCO) films, as contacts. Aluminum doped zinc oxide (AZO) deposited with the Sputtering technique and tin doped indium oxide (ITO) using the pyrolysis spray technique, these transparent and conductive films were deposited as contacts on a film of siliconrich oxide (SRO) which was deposited by two systems of chemical vapor deposition by low-pressure (LPCVD) and by hotfilament (HFCVD) on quartz substrates with polysilicon film as metal contact, with the object of building two Metal-InsulatingMetal (MIM) structures, one with SRO-LPCVD film and another SRO-HFCVD thus highlighting the electrical characteristics of these structures. The precursors used for the LPCVD system are silane (SiH4) and nitrous oxide (N2O) and for the HFCVD system the gaseous precursors are obtained from a solid quartz source stripped with atomic hydrogen. First, we present results of the optical characterizations of the TCO´s and SRO films, the band gap obtained by Tauc to calculate the size of the nanocrystal in SRO-films, causing light spots. And I-V curves of MIM structures with interesting results.