VISIBLE ELECTROLUMINESCENCE FROM CRYSTALLIZED A-SI-H A-SINX-H MULTIQUANTUM-WELL STRUCTURES/

Visible photoluminescence (PL) in crystallized a-Si:H/a-SiNX:H multiqu antum well (MQW) structures is reported for the first time. In this pa per new results are presented on visible electroluminescence (EL) from these novel luminescent structures. The MQW heterostructures consisti ng of 40 layers were formed by PECVD method and then crystallized by A r ion laser annealing technique. The crystallized samples with well la yer thickness, L(S) = 4 nm, showed an intense visible PL peaked simila r to 2.0 eV. The experimental EL cells are of the form of semitranspar ent metal/crystallized a-Si:H/a-SiNX:H MQWs/p(+)-a-Si:H/quartz substra te. When the forward current density reaches a certain value, stable v isible (orange) light is observed by the naked eye. A possible explana tion of this light emission is the radiative recombination due to the carriers injection into quantized states in nano-size Si crystallites within the Si potential wells.