Dramatic improvement of performance of visible hydrogenated amorphous silicon carbide based p-i-n thin-film light-emitting diodes by two-step hydrogenation

The effects of two-step hydrogenation on the performance of visible p-i-n thin-film light-emitting diode (TFLED) have been investigated. The TFLEDs were fabricated by a photochemical vapor deposition (CVD) method, A hydrogenation process was performed in two steps: One was an in situ hydrogenation process using a photo-CVD system and the other an ex situ hydrogenation process using a plasma apparatus after TFLED fabrication. It was found that the performance of visible a-SiC:H-based p-i-n TFLEDs was drastically improved by a two-step hydrogenation process. The threshold voltage decreased by about 3 V, the electroluminescence peak shifted towards a shorter wavelength, from 680 to 590 nm, add the brightness increased from 1.3 to 128 cd/m(2). (C) 1996 American Institute of Physics.