Encontrados 12 documentos, a visualizar página 1 de 2
Disentangling the role of the SnO layer on the pyro-phototronic effect in ZnO-b...
Vieira, E. M. F; Silva, José Pedro Basto; Gwozdz, Katarzyna; Kaim, Adrian; Gomes, Nuno M.; Chahboun, Adil; Gomes, M. J. M.; Correia, José H.Self-powered photodetectors (PDs) have been recognized as one of the developing trends of next-generation optoelectronic devices. Herein, it is shown that by introducing a thin layer of SnO film between the Si substrate and the ZnO film, the self-powered photodetector Al/Si/SnO/ZnO/ITO exhibits a stable and uniform violet sensing ability with high photoresponsivity and fast response. The SnO layer introduces a ...
Low-cost silicon neural probe: fabrication, electrochemical characterization an...
Rodrigues, José Artur Oliveira; Pimenta, Sara; Pereira, José P.; Gomes, Nuno M.; Souto, Márcio R.; Fernandes, Helena C.; Caetano, InêsThis paper presents the fabrication of a silicon neural probe using low-cost microfabrication technologies, such as thin-films deposition, blade dicing, and photolithography. The metal stack that forms the 9 microelectrodes of 50 × 50 µm2 area, the tracks and the pads were made of Ti and Pt, while the passivation stack was SiO2 and Si3N4. The fabricated probe was characterized using electrochemical impedance sp...
PDMS microlenses for focusing light in narrow band imaging diagnostics
Costa, Adriana Clotilde; Pimenta, Sara; Ribeiro, J. F.; Silva, Manuel Fernando Ribeiro; Wolffenbuttel, Reinoud F.; Dong, Tao; Yang, ZhaochuMinimally invasive medical devices can greatly benefit from Narrow Band Imaging (NBI) diagnostic capabilities, as different wavelengths allow penetration of distinct layers of the gastrointestinal tract mucosa, improving diagnostic accuracy and targeting different pathologies. An important performance parameter is the light intensity at a given power consumption of the medical device. A method to increase the i...
Stress affects theta activity in limbic networks and impairs novelty-induced ex...
Jacinto, L. R.; Reis, Joana Vanessa Santos dos; Dias, N. S.; Cerqueira, João; Correia, José H.; Sousa, NunoExposure to a novel environment triggers the response of several brain areas that regulate emotional behaviors. Here, we studied theta oscillations within the hippocampus (HPC)-amygdala (AMY)-medial prefrontal cortex (mPFC) network in exploration of a novel environment and subsequent familiarization through repeated exposures to that same environment; in addition, we assessed how concomitant stress exposure cou...
Effects of the ESD protections in the behaviour of a 2.4 GHz RF transceiver: pr...
Carmo, João Paulo; Mendes, P.M.; Ribeiro, Fernando; Correia, José H.This paper identifies the main problems related to the Electrostatic Discharge (ESD) in submicron CMOS processes. The mitigation of this problem is made with the use of protections, in order to avoid the destruction of the internal and nput/output circuits connected to the bondingpads. In the 2.4 GHz ISM band, the parallel capacitance and the serial resistance of the ESD protections have effects in the behavior...
A 2.4 GHz wireless electronic shirt for vital signals monitoring
Carmo, João Paulo; Mendes, P.M.; Couto, Carlos; Correia, José H.The paper presents a wireless sensor network for wireless electronic shirts. This allows the monitoring of individual biomedical data, such as the cardio-respiratory function. The solution chosen to transmit the body’s measured signals for further processing was the use of a wireless link, working at the 2.4 GHz ISM band. A radio-frequency (RF) CMOS transceiver chip was designed in the UMC RF 0.18 μm CMOS proce...
A 2.4-GHz low-power/low-voltage wireless plug-and-play module for EEG applications
Carmo, João Paulo; Dias, Nuno; Silva, Hélder; Mendes, P.M.; Couto, Carlos; Correia, José H.This paper presents a plug-and-play module for wireless electroencephalogram (EEG) applications. The wireless module is composed by an electrode, processing electronics, a radio-frequency (RF) transceiver, and an associated antenna. The RF transceiver was fabricated in the UMC RF 0.18 mum CMOS process, and operates in the 2.4-GHz ISM band. The receiver has a sensitivity of -60 dBm and a power consumption of 6.3...
A 2.4-GHz wireless sensor network for smart electronic shirts integration
Carmo, João Paulo; Mendes, P.M.; Afonso, José A.; Couto, Carlos; Correia, José H.A typical sensing module is composed of sensors, interface electronics, a radio-frequency (RF) CMOS transceiver and an associated antenna. A 2.4-GHz RF transceiver chip was fabricated in a UMC 0.18 μm CMOS process. The receiver has a sensibility of -60 dBm and consumes 6.3 mW from a 1.8 V supply. The transmitter delivers an output power of 0 dBm with a power consumption of 11.2 mW. Innovative topics concerning ...
5.7 GHz on-chip antenna/RF CMOS transceiver for wireless sensor networkS
Carmo, João Paulo; Mendes, P.M.; Couto, Carlos; Correia, José H.This paper describes a chip-size antenna for operation at 5.7 GHz, assembled with a low-power, low-voltage RF CMOS transceiver, fabricated in UMC RF CMOS 0.18 μm process. Measurements shown a patch antenna with the central frequency of 5.705 GHz, a bandwidth of 90 MHz at −10 dB of return loss, a directive gain of 0.3 dB, with an efficiency of 18%, and a transceiver with a measured total power consumption of 23 ...
Low-power 2.4-GHz RF transceiver for wireless EEG module plug-and-play
Carmo, João Paulo; Dias, Nuno; Mendes, P.M.; Couto, Carlos; Correia, José H.The paper presents the design and fabrication of a radio-frequency (RF) transceiver fabricated in a UMC RF 0.18 µm CMOS process. The RF transceiver was built to operate at the 2.4 GHz ISM band. The receiver has a sensibility of -60 dBm and consumes 6.3 mW from a 1.8 V supply. The transmitter delivers an output power of 0 dBm with a power consumption of 11.2 mW. The application is a wireless wearable electroence...