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© 2016 IOP Publishing Ltd. The authors would like to acknowledge the C A I de Técnicas Físicas of the Universidad Complutense de Madrid for the ion implantations and metallic evaporations, the Nanotechnology and Surface Analysis Services of the Universidad de Vigo C.A.C.T.I. for ToF-SIMS measurements and Dr J P González García from CIEMAT for reflectance measurements. Research by E García-Hemme was supported by a PICATA predoctoral fellowship of the Moncloa Campus of International Excellence (UCM-UPM). J Olea acknowledges financial support from the MICINN within the program Juan de la Cierva (JCI-2011-10402), under which this research was undertaken. D Pastor acknowledges the financial support to the grant EX-2010-0662 from the Spanish Science Ministry. This work was partially supported by the Spanish MINECO (Economic and Competitiviness Ministery) through grant TEC 2013-41730-R. The authors acknowledge the financial support from la Comunidad de Madrid throughout the funding of the project, MADRID-PV (S2013/MAE-2780)., Silicon samples were implanted with high Ti doses and subsequently processed with the pulsed-laser melting technique. The electronic transport properties in the 15–300 K range and the room temperature spectral photoresponse at energies over the bandgap were measured. Samples with Ti concentration below the insulator-metal (I-M) transition limit showed a progressive reduction of the carrier lifetime in the implanted layer as Ti dose is increased. However, when the Ti concentration exceeded this limit, an extraordinary recovery of the photoresponse was measured. This result supports the theory of intermediate band materials and is of utmost relevance for photovoltaic cells and Si-based detectors., Ministerio de Economía y Competitividad (MINECO), Ministerio de Ciencia e Innovación (MICINN), Comunidad de Madrid, Campus de Excelencia Internacional Moncloa UCM-UPM, PICATA Programa Internacional de Captación de Talento Convocatorias Campus Moncloa, Ayudas para contratos Juan de la Cierva (MICINN), Ministerio de Ciencia y Tecnología (MCYT), España, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© American Institute of Physics. This work has been supported by the Spanish Ministry of Science and Technology under Contract Nos. MAT2004-0664 and MAT2004-02875. The authors wish to thank Dr. M. Marsal for her expert assistance with the EDX measurements., We have studied the effects of rapid thermal annealing at 1300 degrees C on GaN epilayers grown on AlN buffered Si(111) and on sapphire substrates. After annealing, the epilayers grown on Si display visible alterations with craterlike morphology scattered over the surface. The annealed GaN/Si layers were characterized by a range of experimental techniques: scanning electron microscopy, optical confocal imaging, energy dispersive x-ray microanalysis, Raman scattering, and cathodoluminescence. A substantial Si migration to the GaN epilayer was observed in the crater regions, where decomposition of GaN and formation of Si3N4 crystallites as well as metallic Ga droplets and Si nanocrystals have occurred. The average diameter of the Si nanocrystals was estimated from Raman scattering to be around 3 nm. Such annealing effects, which are not observed in GaN grown on sapphire, are a significant issue for applications of GaN grown on Si(111) substrates when subsequent high-temperature processing is required., Spanish Ministry of Science and Technology, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

© 2023 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works., In this article, we study the effect of the inversion charge ( Q inv ) in a solar cell based on the hole-selective characteristic of substoichiometric molybdenum oxide (MoO x ) and vanadium oxide (VO x ) deposited directly on n-type silicon. We measure the capacitance–voltage ( C – V ) curves of the solar cells at different frequencies and explain the results taking into account the variation of the space charge and the existence of Q inv in the c-Si inverted region. The high-frequency capacitance measurements follow the Schottky metal–semiconductor theory, pointing to a low inversion charge influence in these measurements. However, for frequencies lower than 20 kHz, an increase in the capacitance is observed, which we relate to the contribution of the inversion charge. In addition, applying the metal–semiconductor theory to the high-frequency measurements, we have obtained the built-in voltage potential and show new evidence about the nature of the conduction process in this structure. This article provides a better understanding of the transition metal oxide/n-type crystalline silicon heterocontact., The authors would like to acknowledge the CAI de Técnicas Físicas of the Universidad Complutense de Madrid. The authors would also like to thank the Mexican grants program CONACyT for its financial collaboration., Peer Reviewed, Postprint (author's final draft)

We present a detailed investigation on the formation of supersaturated GaAs using Ti+ implantation followed by nanosecond Pulsed Laser Melting (PLM). We have synthesized high-crystal quality supersaturated GaAs layers with concentrations of Ti above the insulator to metal transition (Mott limit). The Ti-implanted concentration depth profiles after PLM obtained by Time-of-Flight Secondary Ion Mass Spectroscopy (ToF-SIMS) show a redistribution of Ti impurities within the first hundred nanometers and superficial concentration up to 1 × 1021 cm−3. Raman spectroscopy of these Ti supersaturated, and regrown GaAs samples shows a sharp crystalline peak and tensile strain due to the Ti lattice incorporation. Scanning Transmission Electron Microscopy (STEM) and high-resolution Transmission Electron Microscopy (TEM) images show a good GaAs crystallinity after the PLM process. Energy-Dispersive X-ray Spectroscopy (EDS) reveals an enhanced Ti signal inside bubble-like structures and an appearance of interface oxide layer with all processed samples.

© 2022 IOP Publishing Ltd. Authors wish to acknowledge assistance from CAI de Técnicas Físicas (Unidad de Implantación Iónica) and CAI de Técnicas Químicas (Espectroscopía Raman y Correlación) from the Universidad Complutense de Madrid with the Ion Implantations and Raman measurements, respectively. We also acknowledge Servicio de Nanotecnología y Análisis de Superficies del CACTI de la Universidad de Vigo for ToF-SIMS measurements and ICTS-CNM from Madrid for the SEM images. This work was partially supported by the Projects MADRID-PV2 (P2018/EMT-4308) funded by the Comunidad Autónoma de Madrid with the support from FEDER Funds and Projects SCCell (PID2020-116508RB-I00), HyperPHIR (PID2020-117498RB-I00) and SCALED (PID2019-109215RB-C42), funded by the Spanish Ministry of Science and Innovation. D Caudevilla would also acknowledge the Grant PRE2018-083798, financed by MICINN and European Social Fund. F Pérez-Zenteno would also like to acknowledge Grant 786327 form Mexican grants program CONACyT., In this work we have successfully hyperdoped germanium with tellurium with a concentration peak of 10(21) cm(-3). The resulting hyperdoped layers show good crystallinity and sub-bandgap absorption at room temperature which makes the material a good candidate for a new era of complementary metal-oxide-semiconductor-compatible short-wavelength-infrared photodetectors. We obtained absorption coefficients ci higher than 4.1 x 10(3) cm(-1) at least up to 3 mu m. In this study we report the temperature-dependency electrical properties of the hyperdoped layer measured in van der Pauw configuration. The electrical behaviour of this hyperdoped material can be explained with an electrical bilayer coupling/decoupling model and the values for the isolated hyperdoped layer are a resistivity of 4.25 x 10(-3) Omega.cm with an electron-mobility around -100 cm(2) V-1 s(-1)., Ministerio de Ciencia e innovación (MICINN)., Ministerio de Ciencia e Innovación (MICINN)/FEDER, Comunidad de Madrid/ FEDER, Mexican grants program CONACyT, Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub

According to intermediate band (IB) theory, it is possible to increase the efficiency of a solar cell by boosting its ability to absorb low-energy photons. In this study, we used a hyperdoped semiconductor approach for this theory to create a proof of concept of different silicon-based IB solar cells. Preliminary results show an increase in the external quantum efficiency (EQE) in the silicon sub-bandgap region. This result points to sub-bandgap absorption in silicon having not only a direct application in solar cells but also in other areas such as infrared photodetectors. To establish the transport mechanisms in the hyperdoped semiconductors within a solar cell, we measured the J–V characteristic at different temperatures. We carried out the measurements in both dark and illuminated conditions. To explain the behavior of the measurements, we proposed a new model with three elements for the IB solar cell. This model is similar to the classic two-diodes solar cell model but it is necessary to include a new limiting current element in series with one of the diodes. The proposed model is also compatible with an impurity band formation within silicon bandgap. At high temperatures, the distance between the IB and the n-type amorphous silicon conduction band is close enough and both bands are contacted. As the temperature decreases, the distance between the bands increases and therefore this process becomes more limiting., The authors would like to thank the Physical Sciences Research Assistance Centre (CAI de Técnicas Físicas) of the Complutense University of Madrid. This study was partially funded by Project MADRID-PV2 (P2018/EMT-4308), with aid from the Regional Government of Madrid and the ERDF, by the Spanish Ministry of Science and Innovation/National Research Agency (MCIN/AEI) under grants TEC2017- 84378-R, PID2019-109215RB-C41, PID2020-116508RB-I00 and PID2020- 117498RB-I00. Daniel Caudevilla would like to express his thanks for grant PRE2018-083798, provided by the MICINN and the European Social Fund. Francisco Pérez Zenteno would also like to express his thanks for grant 984933, provided by CONACyT (Mexico)., Peer Reviewed, Postprint (author's final draft)

Objective: Build an Integral Health Care Pathway for the care of patients with lower limb amputation due to traumatic, vascular or diabetes mellitus causes, in order to implement the recommendations of the cpg for amputee patients and guarantee comprehensive health care for this population in Colombia. Methodology: This study is a strategy to improve health care. Carried out by a review of the Methodological Manual for the Development and Implementation of Comprehensive Health Care Pathway, then the development group was created. A process of prioritization and description of required individual interventions was developed based on health care. Evaluation of current care practice with focus groups, formulation of milestones and development of the intervention diagram. Results: 25 individual interventions were prioritized and characterized according to the responsible actor, target population and environment. Expected results in health, quality of service delivery, issues related to equity, as well as the perspective of patients and actors involved with care are shown. Indicators were built for monitoring and implementation of the pathway. Conclusion: With the previous results, the first Integral Health Care Pathway for the Lower Limb Amputee Patient was developed. It intends to guide the actors involved, when executing individual interventions for the diagnosis, treatment and rehabilitation, to impact outcomes in health and equity of this group., Objetivo: Construir uma Rota de Atenção Integral à Saúde do Paciente Amputado do Membro Inferior por causas traumáticas, vasculares ou diabetes mellitus, com a finalização de implementar as recomendações do gpc do paciente amputado e garantir a atenção integral na saúde desta población em Colômbia. Metodologia: Este estudo responde a uma estratégia para melhorar os cuidados de saúde. Foi realizada uma revisão do Manual Metodológico para o Desenvolvimento e Implementação de Rotas Integrais de Atenção à Saúde, criação do grupo de desenvolvimento da rota. Um processo de priorização e descrição das intervenções individuais necessárias foi desenvolvido com base na continuidade dos cuidados de saúde. Avaliação da prática assistencial atual com grupos focais, formulação de marcos e desenvolvimento do diagrama de intervenção. Resultados: 25 intervenções individuais foram priorizadas e caracterizadas de acordo com o ator responsável, população-alvo e ambiente. Determinação dos resultados esperados em saúde, qualidade da prestação de serviços, questões relacionadas a equidade, bem como a perspectiva de pacientes e atores envolvidos no atendimento. Foram construídos indicadores para o monitoramento e implementação da rota. Conclusão: Com os resultados anteriores, foi construída a primeira Rota de Atenção Integral à Saúde do paciente com amputação de membros inferiores por causas traumáticas e neurovasculares, com sua implementação, visando orientar os atores envolvidos na execução de intervenções individuais para a diagnóstico, tratamento e reabilitação, impactar os resultados em saúde e eqüidade dessa população., Objetivo: Presentar el estudio mediante el cual se construyó una ruta integral de atención en salud (RIAS) para la atención del paciente amputado de miembro inferior por causas traumática, vascular o diabetes mellitus, cuyo fin es implementar las recomendaciones de la Guía de práctica clínica del paciente amputado y garantizar la atención integral en salud de esta población en Colombia. Con la ruta se pretende orientar a los actores involucrados en la ejecución de intervenciones individuales para el diagnóstico, el tratamiento y la rehabilitación, e impactar en los desenlaces en salud y equidad de esta población. Metodología: Este estudio responde a una estrategia de mejoramiento de la atención en salud. Para esto, se revisó el Manual metodológico para la elaboración e implementación de las rias; se creó el grupo desarrollador de la ruta; se priorizaron y describieron las intervenciones en función del proceso continuo de atención en salud; se evaluó la práctica asistencial actual con grupos focales de pacientes y profesionales; se formularon los resultados esperados en el proceso de gestión y atención en salud (hitos), y se elaboró el diagrama de la ruta. Resultados: A partir de la Guía de práctica clínica se elaboraron 25 intervenciones individuales priorizadas y caracterizadas según el actor responsable, la población objetivo y el entorno. Para cada una de las intervenciones se presentan resultados esperados en salud, calidad de prestación de servicios, aspectos relacionados con la equidad, y la perspectiva de pacientes y actores involucrados con la atención. Se construyeron los indicadores para el seguimiento e implementación de la ruta. Conclusión: Se construyó la primera ruta integral de atención en salud del paciente con amputación de miembro inferior, de acuerdo con los lineamientos del manual del Ministerio de Salud y de la Protección Social.