CMOS-compatible Hf0.5Zr0.5O2-based ferroelectric memory crosspoints fabricated with damascene process

Abstract

Abstract We report the fabrication of Hf0.5Zr0.5O2 (HZO) based ferroelectric memory crosspoints using a complementary metal-oxide-semiconductor-compatible damascene process. In this work, we compared 12 and 56 µm2 crosspoint devices with the 0.02 mm2 round devices commonly used as a benchmark. For all devices, a 9 nm thick ferroelectric thin film was deposited by plasma-enhanced atomic layer deposition on planarized bottom electrodes. The wake-up appeared to be longer for the crosspoint memories compared to 0.02 mm2 benchmark, while all the devices reached a 2Pr value of ∼50 µC cm−2 after 105 cycles with 3 V/10 µs squared pulses. The crosspoints stand out for their superior endurance, which was increased by an order of magnitude. Nucleation limited switching experiments were performed, revealing a switching time <170 ns for our 12 and 56 µm2 devices, while it remained in the µs range for the larger round devices. The downscaled devices demonstrate notable advantages with a rise in endurance and switching speed.