Tunability of Ferroelectric Hafnium Zirconium Oxide for Varactor Applications

Abdulazhanov, Sukhrob; Lederer, Maximilian; Lehninger, David; Mart, Clemens; Ali, Tarek; Wang, Defu; Olivo, Ricardo; Emara, Jennifer; Kämpfe, Thomas; Gerlach, Gerald

doi:10.1109/ted.2021.3104532

Cited by 11 publications

(11 citation statements)

References 40 publications

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“…[12] Copyright 2020, Wiley-VCH. content as shown experimentally [9,164,177] or using ab initio calculations. [6] Consequently, the highest remanent polarization is expected for films with equal amounts of hafnium and zirconium, that is, Hf 0.5 Zr 0.5 O 2 .…”

Section: Effect Of Film Composition On Ferroelectric Characteristics ...supporting

confidence: 52%

“…It was reported from XRD and TKD analysis that, under the same annealing conditions (i.e., isothermal and isochronic), the fraction of the monoclinic phase scales with HfO 2 for x > 0.5 (see Figure ). [ 12,141 ] On the other side, for the ZrO 2 rich film ( x < 0.5), either the amount of the tetragonal phase and/or the amount of antiferroelectric‐like domains within the orthorhombic phase scales with the ZrO 2 content as shown experimentally [ 9,164,177 ] or using ab initio calculations. [ 6 ] Consequently, the highest remanent polarization is expected for films with equal amounts of hafnium and zirconium, that is, Hf 0.5 Zr 0.5 O 2 .…”

Section: Integrationmentioning

confidence: 92%

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Review on the Microstructure of Ferroelectric Hafnium Oxides

Lederer

Lehninger

Ali

et al. 2022

Physica Rapid Research Ltrs

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Ferroelectric hafnium oxide is of major interest for a multitude of applications in microelectronics, ranging from neuromorphic devices to actuators and sensors. While the electrical performance is commonly discussed in depth, the influence of the microstructure is often disregarded. However, in recent years, more research groups shed light into the microstructural background of ferroelectric behavior in hafnium oxide films. To give a more general and complete picture of the different influences on the microstructure and its relevance for the applications, the process and stack influences on the microstructure are reviewed and summarized. While a few mechanisms are not yet understood in depth, a coherent picture on the formation of the microstructure in ferroelectric hafnium oxide layers can be gained.

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Section: Effect Of Film Composition On Ferroelectric Characteristics ...supporting

confidence: 52%

Section: Integrationmentioning

confidence: 92%

Review on the Microstructure of Ferroelectric Hafnium Oxides

Lederer

Lehninger

Ali

et al. 2022

Physica Rapid Research Ltrs

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“…It was reported that, under the same annealing conditions (i.e., isothermal and isochronic), the fraction of the monoclinic phase will scale with the amount of HfO 2 for x > 0.5. On the other side, for x < 0.5, either the amount of the tetragonal phase and/or the amount of AFE‐like domains within the o ‐phase scale with the ZrO 2 content as shown experimentally [ 46,50,101 ] or by using ab initio calculations. [ 38 ] Consequently, the highest remanent polarization is expected for films with equal amounts of hafnium and zirconium, that is, Hf 0.5 Zr 0.5 O 2 .…”

Section: Memory‐based Applications Of Fluorite‐structured Materialsmentioning

confidence: 99%

Fluorite‐Structured Ferroelectric and Antiferroelectric Materials: A Gateway of Miniaturized Electronic Devices

Ali

Lehninger

et al. 2022

Adv Funct Materials

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Ferroelectric (FE) and antiferroelectric (AFE) materials are used for several memory-related and energy-related applications. Perovskite materials (e.g., bulk ceramics) remain the most common materials for many applications. However, due to large deposition thickness, these materials are not appropriate for future miniaturized devices. In 2011, FE and AFE properties were reported in Si-doped HfO 2 thin films. HfO 2 -based FE and AFE materials have several advantages over conventional materials, such as ultrathin deposition thickness (in range of nanometers), compatibility with existing Si semiconductor technology, and suitability for the integration within 3-D nanostructures. Therefore, fluorite-structured materials can be appropriate for miniaturized devices. These fluorite-structured materials are extensively studied for memory and energy-related applications. The first review on this topic was published after four years of discovering the FE and AFE properties in these materials. From the past decade, a lot of research has been reported about the detailed mechanism and application of these materials. This review insightfully discusses the progress in the research of fluorite-structured materials and critically discusses some potential applications. Here some challenges are also discussed, new knowledge is extracted, and promising future research directions of these materials are suggested.

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“…The peak on the I – V curve is due to displacement currents at the corresponding coercive voltage ( V c ). The pristine I – V and P – V curves show a pinched behavior, which manifests itself in two distinct displacement current peaks, i.e., antiferroelectric-like behavior . Additionally an imprint is present, evident from the peaks’ displacement toward higher potential.…”

Section: Electrical Characterizationmentioning

confidence: 94%

“… 2 The ferroelectric can change its permittivity upon applied bias and performs as a varactor. 3 In comparison to the BST and PZT varactors, the main advantage of ferroelectric HfO 2 is its low annealing temperature, good manufacturing properties for etching and deposition, and low tuning voltages, which makes it perfectly compatible with advanced CMOS node implementation and hence will make it now possible to design much higher frequency varactor-tuned low-power millimeter wave systems such as needed for 6G communications, imaging radar, or THz imaging. When doped with Zr with a 1:1 doping ratio, resulting Hf 0.5 Zr 0.5 O 2 ferroelectricity can be obtained at 400 °C, 3 , 4 which facilitates the integration of the varactor into the back-end-of line of CMOS processes.…”

Section: Introductionmentioning

confidence: 99%

THz Thin Film Varactor Based on Integrated Ferroelectric HfZrO₂

Abdulazhanov

Huynh

et al. 2022

ACS Appl. Electron. Mater.

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In this paper, we present a broadband microwave characterization of ferroelectric hafnium zirconium oxide (Hf 0.5 Zr 0.5 O 2 ) metal−ferroelectric−metal (MFM) thin film varactor from 1 kHz up to 0.11 THz. The varactor is integrated into the back-end-of-line (BEoL) of 180 nm CMOS technology as a shunting capacitor for the coplanar waveguide (CPW) transmission line. At low frequencies, the varactor shows a slight imprint behavior, with a maximum tunability of 15% after the wake-up. In the radio-and mmWave frequency range, the varactor's maximum tunability decreases slightly from 13% at 30 MHz to 10% at 110 GHz. Ferroelectric varactors were known for their frequency-independent, linear tunability as well as low loss. However, this potential was never fully realized due to limitations in integration. Here, we show that ferroelectric HfO 2 thin films with good back-end-of-line compatibility support very large scale integration. This opens up a broad range of possible applications in the mmWave and THz frequency range such as 6G communications, imaging radar, or THz imaging.

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Tunability of Ferroelectric Hafnium Zirconium Oxide for Varactor Applications

Cited by 11 publications

References 40 publications

Review on the Microstructure of Ferroelectric Hafnium Oxides

Review on the Microstructure of Ferroelectric Hafnium Oxides

Fluorite‐Structured Ferroelectric and Antiferroelectric Materials: A Gateway of Miniaturized Electronic Devices

THz Thin Film Varactor Based on Integrated Ferroelectric HfZrO₂

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Tunability of Ferroelectric Hafnium Zirconium Oxide for Varactor Applications

Cited by 11 publications

References 40 publications

Review on the Microstructure of Ferroelectric Hafnium Oxides

Review on the Microstructure of Ferroelectric Hafnium Oxides

Fluorite‐Structured Ferroelectric and Antiferroelectric Materials: A Gateway of Miniaturized Electronic Devices

THz Thin Film Varactor Based on Integrated Ferroelectric HfZrO2

Contact Info

Product

Resources

About

THz Thin Film Varactor Based on Integrated Ferroelectric HfZrO₂