ELECTROLUMINESCENCE OF A-SIC-H P-I-N THIN-FILM LIGHT-EMITTING-DIODES WITH QUANTUM-WELL-INJECTION STRUCTURES

Abstract In order to improve the electroluminescence (EL) characteristics of hydrogenated amorphous silicon carbide (a-SiC:H) p - i - n thin-film light-emitting diodes (TFLEDs), the quantum-well-injection (QWI) structures have been incorporated into their intrinsic ( i -) layer. Two types of TFLED were fabricated to study the effect of the incorporated QWI structures on their EL characteristics: the device I contains a step-gap QWI structure of barrier (15 A)/well (45 A)/barrier (15 A) inserted at both the p - i and i - n interfaces, and the device II has only one graded-gap QWI structure of barrier (10 A)/well (10 A)/barrier (10 A) inserted at the p - i interface. The obtained brightness of device I was about 10 cd/m 2 at an injection current density of 1 A/cm 2 . The emission light of device I was yellow-like as detected by human eyes. Whereas, for device II, the brightness was about 256 cd/m 2 at 800 mA/cm 2 and an orange light emission was observed.