CHARACTERISTICS OF ORGANIC PHOTO-LUMINESCENT AND ELECTRO-LUMINESCENT DEVICES WITH DOUBLE MIRRORS

The luminescent characteristics of organic thin films sandwiched betwe en two mirrors were measured. The optical length between the two mirro rs was set according to the scale of the luminescent wavelength in ord er to compose a microcavity structure. Photoluminescence (PL) and elec troluminescence (EL) from tris(8-hydroxyquinoline)aluminum (ALQ) were enhanced at distinct resonating wavelengths, and suppressed in other r egions. Then, narrow and enhanced luminescent peaks were observed from the devices with the microcavity structure. Based on their injection current dependence, the primary cause of these spectra was speculated to be spontaneous emission. An EL sample with the microcavity structur e for multicolor emissions was fabricated.