ORGANIC THIN-FILM TRANSISTORS FOR ORGANIC LIGHT-EMITTING FLAT-PANEL DISPLAY BACKPLANES

The performance of organic thin-film transistors (OTFT's) has improved significantly in the last several years and it now appears likely tha t they will find application in low-cost large-area electronic applica tions, Active-matrix displays are of special interest and integration of OTFT's with organic light-emitting devices (OLED's) in all-organic displays is particularly attractive, The device requirements for activ e-matrix OLED displays are very similar to those of active-matrix liqu id-crystal displays (AMLCD's) and can be satisfied with OTFT's fabrica ted using stacked pentacene active layers. Such devices have demonstra ted held-effect mobility near 1.5 cm(2)/V.s, on/off current ratio near 10(8), near-zero threshold voltage, and subthreshold slope less than 1.6 V/decade, These characteristics are similar to those obtained with hydrogenated amorphous silicon (a-Si:H) devices and such devices woul d allow the use of polymeric substrates with advantages in weight, rug gedness, and cost compared to glass substrates currently used with a-S i:H devices in AMLCD's.