In this study, we report a novel encapsulation method for longevity of an organic thin-film transistor (OTFT) using pentacene by means of an adhesive multiplayer included At film. For encapsulation of OTFTs, the Al film adhered onto the OTFT in a dry nitrogen atmosphere using a proper adhesive. A lifetime, which was defined as the time necessary to reduce mobility to 2%, of initial mobility value, was observed from the typical I-D-V-D characteristics of the field-effect transistor (FET). The initial field effect mobility, mu, was measured to be 2.0 x 10(-1) cm(2)/V s. The characterization was maintained for long times in air. No substantial degeneration occurred. The performance and the stability are probably due to the encapsulation effect. (c) 2004 Elsevier B.V. All rights reserved.