Encontrados 11 documentos, a visualizar página 1 de 2

Sonda ultra-fina e flexível para aquisição de atividade neuronal

O cérebro humano, com cerca de 86 mil milhões de neurónios, transmite informações de forma complexa. Doenças como epilepsia e Alzheimer afetam a qualidade de vida, tornando essencial o estudo do cérebro para desenvolver tratamentos inovadores. As sondas neuronais implantáveis, que registam ou modulam a atividade neuronal, evoluíram nas últimas décadas e são amplamente utilizadas no tratamento de doenças como Pa...

Sonda ultra-fina e flexível para aquisição de atividade neuronal

Silicon nitride thin-films deposited by radiofrequency reactive sputtering: ref...

Silicon nitride (SiN) is widely used as a core material in optical waveguides due to its optical properties. The deposition of SiN thin-films by radiofrequency (RF) reactive sputtering is commonly used in low-temperature processes, where the thin-films optical properties can be optimized by controlling the deposition parameters (sputtering power, gases ratio, etc.). This work presents the deposition of several ...

Flexible neural probes: a review of the current advantages, drawbacks, and futu...

Brain diseases affect millions of people and have a huge social and economic impact. The use of neural probes for studies in animals has been the main approach to increasing knowledge about neural network functioning. Ultimately, neuroscientists are trying to develop new and more effective therapeutic approaches to treating neurological disorders. The implementation of neural probes with multifunctionalities (e...

PDMS microlenses coating with a SiO2 ultra-thin film deposited by atomic layer ...

The optical characteristics of microlenses are significantly influenced by their surface roughness, which is determined by the fabrication process. High-surface roughness increases light scattering, reducing the optical efficiency of the microlenses. The atomic layer deposition (ALD) technique, known for its high conformity, can minimize the roughness of the substrate, filling the surface voids and smoothing it...

Silicon dioxide atomic layer deposition at low temperature for PDMS microlenses...

The optical performance of a microlens is strongly affected by its surface roughness, which depends on its fabrication process. High-surface roughness leads to scattering issues, decreasing the optical efficiency of a microlens. In this work, a polydimethylsiloxane microlens was coated with a very thin-film of silicon dioxide (30 nm), deposited by plasma-enhanced atomic layer deposition at a low temperature (50...

Flexible neural probe fabrication enhanced with a low-temperature cured polyimi...

Polyimide is an emerging and very interesting material for substrate and passivation of neural probes. However, the standard curing temperature of polyimide (350 °C) is critical for the microelectrodes and contact pads of the neural probe, due to the thermal oxidation of the metals during the passivation process of the neural probe. Here, the fabrication process of a flexible neural probe, enhanced with a photo...

Flexible and reduced-size neural probe using a photosensitive polyimide

The understanding of the human brain function is one of the main challenges of modern science, as it comprises the study of an extremely complex organ. The majority of neural interfaces to study the brain rely on non-flexible and relatively thick structures, which do not adapt to the plastic nature of the brain, damaging the tissue and compromising data acquisition [1, 2]. This research presents the fabrication...

Simulation, fabrication and morphological characterization of a PDMS microlens ...

Optrodes are neural probes for delivering light at neurons, at least with an irradiance of 1 mW/mm2. MicroLED (microlight-emitting diode) optrodes with a microlens to collimate the light can improve the irradiance without increasing the microLED power consumption, minimizing the brain overheating. This paper presents FEM (finite element method) simulations of a PDMS (polydimethylsiloxane) microlens capable of c...

Magnesium fluoride as low-refractive index material for near-ultraviolet filter...

This article describes the fabrication of MgF2 and MgO thin-film-based optical filters and compares the optical transmission of the filters over UV. The MgF2 thin-films were deposited by use of an e-beam technique and their optical properties were characterised by ellipsometry. The effect of substrate temperature on the optical properties was studied. The MgF2 optimum refractive indices were obtained with a sub...