In order to improve the performance of hydrogenated amorphous-silicon carbide (a-SiC:H) p-i-n thin-film light-emitting diodes (TFLED's), a p-i-n TFLED with a graded p-i junction has been proposed and fabricated. The electroluminescence (EL) intensity of the proposed TFLED was more than 100 times higher than that of the basic p-i-n TFLED and about 35 times lower than that of the conventional green LED, at the same injection current density. This significant improvement was attributed to the better interface property and enhancement of hole injection efficiency by using the graded-gap p-i junction.