Nanosecond Laser Anneal (NLA) for Si-Implanted HfO2 Ferroelectric Memories Integrated in Back-End of Line (BEOL)

Ferroelectric Hf0.5Zr0.5O2 Thin Films Crystallized by Pulsed Laser Annealing

“…[1,2] Unlike perovskite materials, doped HfO 2 films are perfectly compatible with the existing complementary metal-oxide-semiconductor technology (e.g., as reported in various studies [3][4][5][6] ) One of the most promising representatives of this class of materials is an alloyed HfO 2 ÀZrO 2 thin film, particularly, at the Hf 0.5 Zr 0.5 O 2 (HZO) stoichiometry, for which the annealing temperature required for the crystallization of the ferroelectric phase is as low as T ¼ 400 C, [7][8][9][10][11] thus potentially enabling to fabricate ferroelectric devices in the back-end-of-line process. [5,6] The experimental studies conducted to date [9][10][11][12][13][14][15] point at the metastable noncentrosymmetric orthorhombic phase (Pbc2 1 or Pca2 1 ) [16] to be responsible for the ferroelectric properties of doped or alloyed HfO 2 films. To stabilize this phase and suppress the formation of an equilibrium monoclinic phase (P2 1 /c), rapid thermal annealing (RTA) process is used.…”

“…[25] Recently, ms PLA was demonstrated to be a powerful tool to "engineer" ferroelectric Si-doped HfO 2 film crystallization. [5] In this work, we explore the effect of both nano-and millisecond annealing of amorphous HZO films in a capacitor structure. We first simulate the temporal temperature evolution across the realistic functional TiN/HZO/W capacitor structure fabricated on different substrates and for different laser pulse durations and then conduct series of experiments, which demonstrate the applicability of PLA for the local crystallization of HZO ferroelectric phase.…”

Advances in Emerging Memory Technologies: From Data Storage to Artificial Intelligence

“…For all of these reasons FeFET are targeting Flash or EEPROM rather than DRAM replacement. In particular, it is now seen as an alternative to Flash for ultra-low power applications [91], due to its 10 fJ/bit consumption and five-nanosecond programming speed. FeFET based eNVM solutions were integrated into leading edge technologies: GlobalFoundries FeFET technology was embedded into the 28 nm gate first HKMG low power CMOS platform, showing 6δ distribution, reasonable endurance, and stable data retention [95].…”

Ferroelectrics Based on HfO2 Film

“…Various annealing process can be used to induce ferroelectricity in HfO 2 including RTA [58,61,62], furnace [49,63], hot plate [64], flash lamp [65], and laser [66,67] techniques. Among them, RTA is the most commonly used method for the crystallization of ferroelectric HfO 2 , and post-deposition annealing (PDA) and post-metallization annealing (PMA) can be used.…”

“…Therefore, to employ ferroelectric HfO 2 on a flexible device, it will be necessary to introduce a fundamentally low-temperature process. If new heat treatment methods, such as DUV irradiation (Figure 4a) [70], flash lamp [65], laser (Figure 4b) [66,67], etc., can be applied for low temperature processing, or the existing RTA technology can be made applicable at low temperature [71][72][73], it would open the door for ferroelectric HfO 2 -based flexible devices.…”