The fabrication and performance characteristics of a new kind of thin-film transistor is presented. The novelty consists of the use of a thin polymer film as an insulator between gate and semiconductor film. The insulator used is polytetrafluoroethylene film, evaporated by an electron gun. The semiconductor used is a tellurium film, evaporated by resistive heating. The transistor shows useful current/voltage characteristics, but the isulator and the insulator – semiconductor interface show slow-drift phenomena, analogous to the drift seen in most conventional thin-film transistors with an inorganic insulator film.