Graded-gap a-SiC:H p-i-n thin-film light-emitting diodes

Electrical and luminescent characteristics of a-SiC:H p-i-n thin-film LED'S with graded-gap junctions

“…A schematic cross section of the DG TFLED is shown in Fig. 1 [12], whereas that for the SG TFLED has only a single graded-gap junction at the p-i interface and its i-layer thickness is 470Å [11]. After a standard cleaning process, an indiumtin-oxide (ITO) coated glass substrate was transferred into a plasma-enhanced chemical vapor deposition (PECVD) system (ULVAC CPD-1108D) which was used for depositing various amorphous thin-films.…”

“…This can be ascribed to a) the stabilization effect resulting from the reaction of hydrogen links with silicon dangling bonds on the surface being covered with hydrogen atoms, and b) the cleaning effect coming from the reactive hydrogen interacts with impurities on the surface, such as oxygen and carbon, and then removes them by cleaning volatile species [13]. The reason to replace the CF -O -plasma treatment, which was used in fabrication of the SG TFLED [11], by an H -plasma treatment is that it has less contamination to the following films to be deposited [13], [14].…”

“…Therefore, it is necessary to reduce notch barriers to enhance carrier transport and hence obtain a higher EL intensity at a lower forward-bias of TFLED. Consequently, a single graded-gap (SG) p-i interface can be used for improving the brightness of an -SiC:H p-i-n TFLED [11], since the increased hole current plays an important role in radiative recombination and, hence, EL properties of TFLED's [5], [11]. In addition, a double graded-gap (DG) structure which has graded-gap p-i and i-n interfaces enhances the device brightness significantly and reduces its EL threshold voltage ( ) substantially [12].…”

Characterization of nanocrystalline silicon carbide films

“…Due to its fine tunable electrical and optical properties by plasma parameters, hydrogenated amorphous silicon carbide films have attracted a great interest and have been used in many kinds of optoelectronic devices, such as solar cell windows layer, color sensors, and thin film light emitting and detecting devices [1][2][3][4][5]. Crystalline SiC compared to its amorphous counterpart has been considered to be a promising semiconductor material to operate at high temperature, high power, high frequency, and high radiation environment due to its good electrical and mechanical characteristics such as electron mobility (1000 cm 2 /V s), electron saturation velocity (2.0-2.7 · 10 7 cm/s), break electronic field (2-3 · 10 6 V/cm), high melting point and high thermal conductivity [6].…”

Estudo e caracterização de filmes de a-Si1-xCx:H obtidos por PECVD visando sua aplicação em MEMS e dispositivos ópticos.

“…Paralelamente aos avanços e pesquisas com c-SiC, no ano de 1977, [21]; no emissor em transistores de base metálica para aplicações de alta freqüência [22]; como semicondutor em transistores de filme fino [23]; em diodos emissores de luz de filme fino (TFLEDs) com estrutura P-I-N [24]; em sensores de cores baseados em fototransistores com estrutura P-I-N [25], [26]; em dispositivos eletroluminescentes [27]; entre outros.…”