Forming-Free, Fast, Uniform, and High Endurance Resistive Switching From Cryogenic to High Temperatures in W/AlOx/Al2O3/Pt Bilayer Memristor

Through oxygen profile engineering, we fabricated W/AlO
_x
/Al
₂
O
₃
/Pt bilayer memristors with a 250-nm feature size. The AlOX fabricated by sputtering serves as an oxygen vacancy source, whereas the Al
₂
O
₃
deposited by atomic layer deposition acts as a dominant resistive switching (RS) layer. Our devices show forming-free RS behaviors with high speed (28 ns), uniform resistance distribution, large on/off ratio (~10
³
@100K, ~10
³
@298K, and ~80@400K), and good retention. Besides, temperature stability with record high endurance from cryogenic to high-temperature (10
⁸
@100K, 10
¹⁰
@298K, and 10
⁷
@400K) is demonstrated, to the best of our knowledge.