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We report on the effect of the Hf0.5Zr0.5O2 (HZO) film thickness on the ferroelectric and dielectric properties using pulse write/read measurements. HZO films of thicknesses ranging from 5 to 20 nm were annealed at 400 °C for 1 min in a nitrogen ambient to be compatible with the back-end of the line thermal budget. As the HZO film thickness decreases, low-voltage operation (1.0 V or less) can be achieved without the dead layer effect, although switching polarization (Psw) tends to decrease due to the smaller grain size. Meanwhile, for 20-nm-thick HZO films prepared under the identical stress (similar TiN top electrode thickness and thermal budget), the Psw and dielectric constant are reduced because of additional monoclinic phase formation. [ABSTRACT FROM AUTHOR]

We report on atomic layer deposited Hf0.5Zr0.5O2 (HZO)-based capacitors which exhibit excellent ferroelectric (FE) characteristics featuring a large switching polarization (45 μC/cm2) and a low FE saturation voltage (~1.5V) as extracted from pulse write/read measurements. The large FE polarization in HZO is achieved by the formation of a non-centrosymmetric orthorhombic phase, which is enabled by the TiN top electrode (TE) having a thickness of at least 90 nm. The TiN films are deposited at room temperature and annealed at 400 ºC in an inert environment for at least 1 min in a rapid thermal annealing system. The room-temperature deposited TiN TE acts as a tensile stressor on the HZO film during the annealing process. The stress-inducing TiN TE is shown to inhibit the formation of the monoclinic phase during HZO crystallization, forming an orthorhombic phase that generates a large FE polarization, even at low process temperatures. [ABSTRACT FROM AUTHOR]

In this paper, the effect of atomic layer deposited ZrO2 gate dielectrics, deposited at low temperature (100 °C), on the characteristics of recessed-gate High Electron Mobility Transistors (HEMTs) on Al0.25Ga0.75N/GaN/Si is investigated and compared with the characteristics of those with ZrO2 films deposited at typical atomic layer deposited (ALD) process temperatures (250°C). Negligible hysteresis (ΔVth <20 mV), low gate leakage current (Ig@2V = 6.6 X 10-66A/cm2), high breakdown voltage(>4 V), and low interfacial state density (Dit = 3.69 X 1011 eV-1cm-2) were observed on recessed gate HEMTs with ~5 nm ALD-ZrO2 films grown at 100°C. The excellent properties of recessed gate HEMTs are due to the absence of an interfacial layer and an amorphous phase of the film. An interfacial layer between 250°CZrO2 and GaN is observed via highresolution transmission electron microscopy and X-ray photoelectron spectroscopy. However, 100°C-ZrO2 and GaN shows no significant interfacial layer formation. Moreover, while 100°C-ZrO2 films maintain an amorphous phase on either substrate (GaN and Si), 250°C-ZrO2 films exhibit a polycrystalline-phase when deposited on GaN and an amorphous phase when deposited on Si. Contrary to popular belief, the lowtemperature ALD process for ZrO2 results in excellent HEMT performance. [ABSTRACT FROM AUTHOR]

With the continued miniaturization of devices in the semiconductor industry, atomic layer deposition (ALD) of silicon nitride thin films (SiNx) has attracted great interest due to the inherent benefits of this process compared to other silicon nitride thin film deposition techniques. These benefits include not only high conformality and atomic-scale thickness control, but also low deposition temperatures. Over the past 20 years, recognition of the remarkable features of SiNx ALD, reinforced by experimental and theoretical investigations of the underlying surface reaction mechanism, has contributed to the development and widespread use of ALD SiNx thin films in both laboratory studies and industrial applications. Such recognition has spurred ever-increasing opportunities for the applications of the SiNx ALD technique in various arenas. Nevertheless, this technique still faces a number of challenges, which should be addressed through a collaborative effort between academia and industry. It is expected that the SiNx ALD will be further perceived as an indispensable technique for scaling next-generation ultra-large-scale integration (ULSI) technology. In this review, the authors examine the current research progress, challenges and future prospects of the SiNx ALD technique. [ABSTRACT FROM AUTHOR]

Increasing interest in the development of alternative energy storage technologies has led to efforts being taken to improve the energy density of dielectric capacitors with high power density. However, dielectric polymer materials still have low energy densities because of their low dielectric constant, whereas Pb-based materials are limited by environmental issues and regulations. Here, the energy storage behaviors of atomic layer-deposited Hf 1- X Zr X O 2 ( X = 0-1) thin films (10 nm) and the phase transformation mechanism associated with an enhancement of their energy density are reported using unipolar pulse measurements. Based on electrical and material characterization, the energy density and energy efficiency are dependent on the Zr content, and stress-induced crystallization by the encapsulating Hf 1- X Zr X O 2 films with TiN top electrodes prior to annealing can enhance the energy density (up to 47 J/cm 3 at a small voltage value of 3.5 MV/cm) while minimizing energy loss even at low process temperatures (400 °C). This work will facilitate the realization of Hf 1- X Zr X O 2 -based capacitors for lead-free electrostatic energy storage applications.

With the continued miniaturization of devices in the semiconductor industry, atomic layer deposition (ALD) of silicon nitride thin films (SiN x ) has attracted great interest due to the inherent benefits of this process compared to other silicon nitride thin film deposition techniques. These benefits include not only high conformality and atomic-scale thickness control, but also low deposition temperatures. Over the past 20 years, recognition of the remarkable features of SiN x ALD, reinforced by experimental and theoretical investigations of the underlying surface reaction mechanism, has contributed to the development and widespread use of ALD SiN x thin films in both laboratory studies and industrial applications. Such recognition has spurred ever-increasing opportunities for the applications of the SiN x ALD technique in various arenas. Nevertheless, this technique still faces a number of challenges, which should be addressed through a collaborative effort between academia and industry. It is expected that the SiN x ALD will be further perceived as an indispensable technique for scaling next-generation ultra-large-scale integration (ULSI) technology. In this review, the authors examine the current research progress, challenges and future prospects of the SiN x ALD technique.