Electrical characterization of amorphous silicon MIS-based structures for HIT solar cell applications

A complete electrical characterization of hydrogenated amorphous silicon layers (a-Si:H) deposited on crystalline silicon (c-Si) substrates by electron cyclotron resonance chemical vapor deposition (ECR-CVD) was carried out. These structures are of interest for photovoltaic applications. Different growth temperatures between 30 and 200 °C were used. A rapid thermal annealing in forming gas atmosphere at 200 °C during 10 min was applied after the metallization process. The evolution of interfacial state density with the deposition temperature indicates a better interface passivation at higher growth temperatures. However, in these cases, an important contribution of slow states is detected as well. Thus, using intermediate growth temperatures (100–150 °C) might be the best choice.

Deposition of Intrinsic a-Si:H by ECR-CVD to Passivate the Crystalline Silicon Heterointerface in HIT Solar Cells

We have deposited intrinsic amorphous silicon (a-Si:H) using the electron cyclotron resonance (ECR) chemical vapor deposition technique in order to analyze the a-Si:H/c-Si heterointerface and assess the possible application in heterojunction with intrinsic thin layer (HIT) solar cells. Physical characterization of the deposited films shows that the hydrogen content is in the 15-30% range, depending on deposition temperature. The optical bandgap value is always comprised within the range 1.9- 2.2 eV. Minority carrier lifetime measurements performed on the heterostructures reach high values up to 1.3 ms, indicating a well-passivated a-Si:H/c-Si heterointerface for deposition temperatures as low as 100°C. In addition, we prove that the metal-oxide- semiconductor conductance method to obtain interface trap distribution can be applied to the a-Si:H/c-Si heterointerface, since the intrinsic a-Si:H layer behaves as an insulator at low or negative bias. Values for the minimum of D_it as low as 8 × 10^10 cm^2 · eV^-1 were obtained for our samples, pointing to good surface passivation properties of ECR-deposited a-Si:H for HIT solar cell applications.

Eficacia de la infiltración de Plasma Rico en Plaquetas (PRP) en pacientes diagnosticados del Síndrome de la Fascia Plantar (SFP) desde el punto de vista clínico y funcional

On the basis of the knowledge that the entheses between the plantar fascia and the calcaneus may exhibit a varied pathology, we considered the need to value the pathological factors by illustrating the anatomical changes in the Plantar Fascia Syndrome (PFS) with easy-to-obtain images which allowed us to substantiate our claims. Accordingly, we analized the anatomical (Orts Llorca, 1977; Llusá, 2007; Sobotta, 2007; Domenech Mateu, 2012; Rodriguez Baeza 2012) and biomechanical (Arandes, 1956; Viladot 1979; Caturla, 2001; Safe, 2001) literature in order to better know the location of the pathology and also to assess the functional reasons that could favor this disease. A study of the affected area by Nuclear Magnetic Resonance (NMR) revealed the presence of bone affections such as bone edema, subchondral lesions and several other bone pathologies together with fascia intrinsic injuries such as myxoid degeneration, intrasubstance fissures and perifascial edematous lesions (Larroca, 2013; Conejero, 2014). Injuries not properly treated during the acute phase can evolve into chronic processes which, month after month, become ever more difficult to resolve. In addition, as seen throughout this study, there are changes in the anatomical normality of the foot usually associated with pathological conditions of the plantar fascia. Once the pathological aspects of PFS are identified and their location is established, clinical manifestations should be registered in order to define this syndrome. Pain is the main symptom in patients with PFS and is associated, in many occasions, with tightness or stiffness of the plantar area, limited mobility of the arch of the ankle and, inevitably, a progressive functional deterioration. Thus, that sharp and stabbing pain felt when one puts the foot on the floor after a period of rest located in the front lower face of the heel and irradiating and/or projecting to the middle of the sole of the foot would be synonymous with Plantar Fascia Syndrome (PFS)...