Epitaxial all-perovskite ferroelectric field effect transistor with a memory retention

All-perovskite ferroelectric field effect transistors (FET) are proposed, and switching behaviors of the prototype devices having a (Pb,La)(Zr,Ti)O₃ as a gate insulator and a La_1.99Sr_0.01CuO₄ as a channel layer were demonstrated. Marked improvements in device performances were obtained as compared with the previous ferroelectric FETs. Namely, the present device was written and erased at an operating voltage of 7 V with a pulse width of less than 1 ms, yielding resistance modulation up to about 10% and retaining its memory for more than 10 days at room temperature. Examinations show that the switching speed was limited by a delay constant and can therefore be improved up to 1 μs, and that the memory retention may not be limited by an intrinsic ferroelectric instability as previously suggested.