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Kim, Yujin, Liu, Zhan, Jiang, Hao, Ma, T.P., Zheng, Jun-Fei, Chen, Phil, Condo, Eric, Hendrix, Bryan, O'Neill, James A..  2022.  A Study on the Hf0.5Zr0.5O2 Ferroelectric Capacitors fabricated with Hf and Zr Chlorides. 2022 China Semiconductor Technology International Conference (CSTIC). :1–3.
Ferroelectric capacitor memory devices with carbon-free Hf0.5Zr0.5O2 (HZO) ferroelectric films are fabricated and characterized. The HZO ferroelectric films are deposited by ALD at temperatures from 225 to 300°C, with HfCl4 and ZrCl4 as the precursors. Residual chlorine from the precursors is measured and studied systematically with various process temperatures. 10nm HZO films with optimal ALD growth temperature at 275°C exhibit remanent polarization of 25µC/cm2 and cycle endurance of 5×1011. Results will be compared with those from HZO films deposited with carbon containing metal-organic precursors.
Ali, T., Olivo, R., Kerdilès, S., Lehninger, D., Lederer, M., Sourav, D., Royet, A-S., Sünbül, A., Prabhu, A., Kühnel, K. et al..  2022.  Study of Nanosecond Laser Annealing on Silicon Doped Hafnium Oxide Film Crystallization and Capacitor Reliability. 2022 IEEE International Memory Workshop (IMW). :1–4.
Study on the effect of nanosecond laser anneal (NLA) induced crystallization of ferroelectric (FE) Si-doped hafnium oxide (HSO) material is reported. The laser energy density (0.3 J/cm2 to 1.3 J/cm2) and pulse count (1.0 to 30) variations are explored as pathways for the HSO based metal-ferroelectric-metal (MFM) capacitors. The increase in energy density shows transition toward ferroelectric film crystallization monitored by the remanent polarization (2Pr) and coercive field (2Ec). The NLA conditions show maximum 2Pr (\$\textbackslashsim 24\textbackslash \textbackslashmu\textbackslashmathrmC/\textbackslashtextcmˆ2\$) comparable to the values obtained from reference rapid thermal processing (RTP). Reliability dependence in terms of fatigue (107 cycles) of MFMs on NLA versus RTP crystallization anneal is highlighted. The NLA based MFMs shows improved fatigue cycling at high fields for the low energy densities compared to an RTP anneal. The maximum fatigue cycles to breakdown shows a characteristic dependence on the laser energy density and pulse count. Leakage current and dielectric breakdown of NLA based MFMs at the transition of amorphous to crystalline film state is reported. The role of NLA based anneal on ferroelectric film crystallization and MFM stack reliability is reported in reference with conventional RTP based anneal.
ISSN: 2573-7503
Ergün, Salih, Maden, Fatih.  2021.  An ADC Based Random Number Generator from a Discrete Time Chaotic Map. 2021 26th IEEE Asia-Pacific Conference on Communications (APCC). :79—82.
This paper introduces a robust random number generator that based on Bernoulli discrete chaotic map. An eight bit SAR ADC is used with discrete time chaotic map to generate random bit sequences. Compared to RNGs that use the continuous time chaotic map, sensitivity to process, voltage and temperature (PVT) variations are reduced. Thanks to utilizing switch capacitor circuits to implement Bernoulli chaotic map equations, power consumption decreased significantly. Proposed design that has a throughput of 500 Kbit/second is implemented in TSMC 180 nm process technology. Generated bit sequences has successfully passed all four primary tests of FIPS-140-2 test suite and all tests of NIST 820–22 test suite without post processing. Furthermore, data rate can be increased by sacrificing power consumption. Hence, proposed architecture could be utilized in high speed cryptography applications.
Szolga, L.A., Groza, R.G..  2020.  Phosphor Based White LED Driver by Taking Advantage on the Remanence Effect. 2020 IEEE 26th International Symposium for Design and Technology in Electronic Packaging (SIITME). :265–269.
This paper presents the development of a control circuit to enhance the performances of LED lamps. In this direction, a comparison between the luminous intensity of normal LED based lamps and mid-power ones, for both continuous and switching conditions has been made. The already well know control technologies were analyzed and a study was conducted to increase the lighting performances by rising the operating frequency and magnifying the contribution of remanence effect and thus increasing the efficiency of the light source. To achieve this, in the first stage of the project the power and control circuits have been modeled, related to desired parameters and tested in simulation software. In the second stage, the proposed circuit was implemented by functional blocks and in the last stage, tests were made on the circuit and on light sources in order to process the results. The power consumption has been decreased nearly to a half of it and the luminous flux raised with 15% due to overcurrent and remanence effect that we used.
Ragchaa, Byambajav, Wu, Liji, Zhang, Xiangmin, Chu, Honghao.  2020.  A Multi-Channel 12 bit, 100Ksps 0.35um CMOS ADC IP core for Security SoC. 2020 IEEE 15th International Conference on Solid-State Integrated Circuit Technology (ICSICT). :1—3.
This paper presents a multi-channel, 12 bit, ADC IP core with programmable gain amplifier which is implemented as part of novel Security SoC. The measurement results show that effective number of bits (ENOB) of the ADC IP core reaches 8 bits, SNDR of 47.14dB and SFDR of 56.55dB at 100Ksps sampling rate. The input voltage range is 0V to 3.3V, active die area of 700um*620um in 0.35um CMOS process, and the ADC consumes 22mW in all channel auto-scan mode at 3.3V power supply.
Yang, S., Liu, S., Huang, J., Su, H., Wang, H..  2020.  Control Conflict Suppressing and Stability Improving for an MMC Distributed Control System. IEEE Transactions on Power Electronics. 35:13735–13747.
Compared with traditional centralized control strategies, the distributed control systems significantly improve the flexibility and expandability of an modular multilevel converter (MMC). However, the stability issue in the MMC distributed control system with the presence of control loop coupling interactions is rarely discussed in existing research works. This article is to improve the stability of an MMC distributed control system by inhibiting the control conflict due to the coupling interactions among control loops with incomplete control information. By modeling the MMC distributed control system, the control loop coupling interactions are analyzed and the essential cause of control conflict is revealed. Accordingly, a control parameter design principle is proposed to effectively suppress the disturbances from the targeted control conflict and improve the MMC system stability. The rationality of the theoretical analysis and the effectiveness of the control parameter design principle are confirmed by simulation and experimental results.
Sehatbakhsh, N., Yilmaz, B. B., Zajic, A., Prvulovic, M..  2020.  A New Side-Channel Vulnerability on Modern Computers by Exploiting Electromagnetic Emanations from the Power Management Unit. 2020 IEEE International Symposium on High Performance Computer Architecture (HPCA). :123—138.

This paper presents a new micro-architectural vulnerability on the power management units of modern computers which creates an electromagnetic-based side-channel. The key observations that enable us to discover this sidechannel are: 1) in an effort to manage and minimize power consumption, modern microprocessors have a number of possible operating modes (power states) in which various sub-systems of the processor are powered down, 2) for some of the transitions between power states, the processor also changes the operating mode of the voltage regulator module (VRM) that supplies power to the affected sub-system, and 3) the electromagnetic (EM) emanations from the VRM are heavily dependent on its operating mode. As a result, these state-dependent EM emanations create a side-channel which can potentially reveal sensitive information about the current state of the processor and, more importantly, the programs currently being executed. To demonstrate the feasibility of exploiting this vulnerability, we create a covert channel by utilizing the changes in the processor's power states. We show how such a covert channel can be leveraged to exfiltrate sensitive information from a secured and completely isolated (air-gapped) laptop system by placing a compact, inexpensive receiver in proximity to that system. To further show the severity of this attack, we also demonstrate how such a covert channel can be established when the target and the receiver are several meters away from each other, including scenarios where the receiver and the target are separated by a wall. Compared to the state-of-the-art, the proposed covert channel has \textbackslashtextgreater3x higher bit-rate. Finally, to demonstrate that this new vulnerability is not limited to being used as a covert channel, we demonstrate how it can be used for attacks such as keystroke logging.

Wang, Y., Huang, F., Hu, Y., Cao, R., Shi, T., Liu, Q., Bi, L., Liu, M..  2018.  Proton Radiation Effects on Y-Doped HfO2-Based Ferroelectric Memory. IEEE Electron Device Letters. 39:823–826.
In this letter, ferroelectric memory performance of TiN/Y-doped-HfO2 (HYO)/TiN capacitors is investigated under proton radiation with 3-MeV energy and different fluence (5e13, 1e14, 5e14, and 1e15 ions/cm2). X-ray diffraction patterns confirm that the orthorhombic phase Pbc21 of HYOfilm has no obvious change after proton radiation. Electrical characterization results demonstrate slight variations of the permittivity and ferroelectric hysteresis loop after proton radiation. The remanent polarization (2Pr) of the capacitor decreases with increasing proton fluence. But the decreasing trend of 2Pr is suppressed under high electric fields. Furthermore, the 2Pr degradation with cycling is abated by proton radiation. These results show that the HYO-based ferroelectric memory is highly resistive to proton radiation, which is potentially useful for space applications.
Makhoul, Rawad, Maynard, Xavier, Perichon, Pierre, Frey, David, Jeannin, Pierre-Olivier, Lembeye, Yves.  2018.  A Novel Self Oscillating Class Phi2 Inverter Topology. 2018 2nd European Conference on Electrical Engineering and Computer Science (EECS). :7—10.

The class φ2 is a single transistor, fast transient inverter topology often associated with power conversion at very high frequency (VHF: 30MHz-300MHz). At VHF, gate drivers available on the market fail to provide the adequate transistor switching signal. Hence, there is a need for new power topologies that do no make use of gate drivers but are still suitable for power conversion at VHF. In This paper, we introduce a new class φ;2 topology that incorporates an oscillator, which takes the drain signal through a feedback circuit in order to force the transistor switching. A design methodology is provided and a 1MHz 20V input prototype is built in order to validate the topology behaviour.

de Almeida Arantes, Daniel, Borges da Silva, Luiz Eduardo, Teixeira, Carlos Eduardo, Campos, Mateus Mendes, Lambert-Torres, Germano, Bonaldi, Erik Leandro, de Lacerda de Oliveira, Levy Ely, da Costa, Germando Araújo.  2019.  Relative Permittivity Meter Using a Capacitive Sensor and an Oscillating Current Source. IECON 2019 - 45th Annual Conference of the IEEE Industrial Electronics Society. 1:806—811.

The relative permittivity (also known as dielectric constant) is one of the physical properties that characterize a substance. The measurement of its magnitude can be useful in the analysis of several fluids, playing an important role in many industrial processes. This paper presents a method for measuring the relative permittivity of fluids, with the possibility of real-time monitoring. The method comprises the immersion of a capacitive sensor inside a tank or duct, in order to have the inspected substance as its dielectric. An electronic circuit is responsible for exciting this sensor, which will have its capacitance measured through a quick analysis of two analog signals outputted by the circuit. The developed capacitance meter presents a novel topology derived from the well-known Howland current source. One of its main advantages is the capacitance-selective behavior, which allows the system to overcome the effects of parasitic resistive and inductive elements on its readings. In addition to an adjustable current output that suits different impedance magnitudes, it exhibits a steady oscillating behavior, thus allowing continuous operation without any form of external control. This paper presents experimental results obtained from the proposed system and compares them to measurements made with proven and calibrated equipment. Two initial capacitance measurements performed with the system for evaluating the sensor's characteristics exhibited relative errors of approximately 0.07% and 0.53% in comparison to an accurate workbench LCR meter.

Guo, Xiaolong, Zhu, Huifeng, Jin, Yier, Zhang, Xuan.  2019.  When Capacitors Attack: Formal Method Driven Design and Detection of Charge-Domain Trojans. 2019 Design, Automation Test in Europe Conference Exhibition (DATE). :1727–1732.

The rapid growth and globalization of the integrated circuit (IC) industry put the threat of hardware Trojans (HTs) front and center among all security concerns in the IC supply chain. Current Trojan detection approaches always assume HTs are composed of digital circuits. However, recent demonstrations of analog attacks, such as A2 and Rowhammer, invalidate the digital assumption in previous HT detection or testing methods. At the system level, attackers can utilize the analog properties of the underlying circuits such as charge-sharing and capacitive coupling effects to create information leakage paths. These new capacitor-based vulnerabilities are rarely covered in digital testings. To address these stealthy yet harmful threats, we identify a large class of such capacitor-enabled attacks and define them as charge-domain Trojans. We are able to abstract the detailed charge-domain models for these Trojans and expose the circuit-level properties that critically contribute to their information leakage paths. Aided by the abstract models, an information flow tracking (IFT) based solution is developed to detect charge-domain leakage paths and then identify the charge-domain Trojans/vulnerabilities. Our proposed method is validated on an experimental RISC microcontroller design injected with different variants of charge-domain Trojans. We demonstrate that successful detection can be accomplished with an automatic tool which realizes the IFT-based solution.

Yue, Lu, Yao, Xiu.  2019.  Sub-Modular Circuit Design for Self-Balancing Series-Connected IGBTs in a Modular Multilevel Converter. 2019 IEEE Applied Power Electronics Conference and Exposition (APEC). :3448–3452.

Series-connected IGBTs, when properly controlled, operate similarly to a single device with a much higher voltage capacity. Integrating series IGBTs into a Modular Multilevel Converter (MMC) can reduce its complexity without compromising the voltage capacity. This paper presents the circuit design on the sub-modular level of a MMC in which all the switching devices are series-connected IGBTs. The voltage sharing among the series IGBTs are regulated in a self-balancing manner. Therefore, no central series IGBT controller is needed, which greatly reduces the sensing and communication complexities, increasing the flexibility and expandability. Hardware experiment results demonstrate that the series IGBTs are able to self-regulate the voltage sharing in a fast and accurate manner and the system can operate similarly to a sub-module in a MMC.

Ferres, E., Immler, V., Utz, A., Stanitzki, A., Lerch, R., Kokozinski, R..  2018.  Capacitive Multi-Channel Security Sensor IC for Tamper-Resistant Enclosures. 2018 IEEE SENSORS. :1–4.
Physical attacks are a serious threat for embedded devices. Since these attacks are based on physical interaction, sensing technology is a key aspect in detecting them. For highest security levels devices in need of protection are placed into tamper-resistant enclosures. In this paper we present a capacitive multi-channel security sensor IC in a 350 nm CMOS technology. This IC measures more than 128 capacitive sensor nodes of such an enclosure with an SNR of 94.6 dB across a 16×16 electrode matrix in just 19.7 ms. The theoretical sensitivity is 35 aF which is practically limited by noise to 460 aF. While this is similar to capacitive touch technology, it outperforms available solutions of this domain with respect to precision and speed.
Rajagopalan, S., Rethinam, S., Deepika, A. N., Priyadarshini, A., Jyothirmai, M., Rengarajan, A..  2017.  Design of Boolean Chaotic Oscillator Using CMOS Technology for True Random Number Generation. 2017 International Conference on Microelectronic Devices, Circuits and Systems (ICMDCS). :1–6.

True random numbers have a fair role in modern digital transactions. In order to achieve secured authentication, true random numbers are generated as security keys which are highly unpredictable and non-repetitive. True random number generators are used mainly in the field of cryptography to generate random cryptographic keys for secure data transmission. The proposed work aims at the generation of true random numbers based on CMOS Boolean Chaotic Oscillator. As a part of this work, ASIC approach of CMOS Boolean Chaotic Oscillator is modelled and simulated using Cadence Virtuoso tool based on 45nm CMOS technology. Besides, prototype model has been implemented with circuit components and analysed using NI ELVIS platform. The strength of the generated random numbers was ensured by NIST (National Institute of Standards and Technology) Test Suite and ASIC approach was validated through various parameters by performing various analyses such as frequency, delay and power.

Zhang, F., Masna, N. V. R., Bhunia, S., Chen, C., Mandal, S..  2017.  Authentication and Traceability of Food Products through the Supply Chain Using NQR Spectroscopy. 2017 IEEE Biomedical Circuits and Systems Conference (BioCAS). :1–4.

Maintaining the security and integrity of our food supply chain has emerged as a critical need. In this paper, we describe a novel authentication approach that can significantly improve the security of the food supply chain. It relies on applying nuclear quadrupole resonance (NQR) spectroscopy to authenticate the contents of packaged food products. NQR is a non-invasive, non-destructive, and quantitative radio frequency (RF) spectroscopic technique. It is sensitive to subtle features of the solid-state chemical environment such that signal properties are influenced by the manufacturing process, thus generating a manufacturer-specific watermark or intrinsic tag for the product. Such tags enable us to uniquely characterize and authenticate products of identical composition but from different manufacturers based on their NQR signal parameters. These intrinsic tags can be used to verify the integrity of a product and trace it through the supply chain. We apply a support vector machine (SVM)-based classification approach that trains the SVM with measured NQR parameters and then authenticates food products by checking their test responses. Measurement on an example substance using semi-custom hardware shows promising results (95% classification accuracy) which can be further improved with improved instrumentation.

Moukarzel, M., Eisenbarth, T., Sunar, B..  2017.  \#x03BC;Leech: A Side-Channel Evaluation Platform for IoT. 2017 IEEE 60th International Midwest Symposium on Circuits and Systems (MWSCAS). :25–28.

We propose $μ$Leech, a new embedded trusted platform module for next generation power scavenging devices. Such power scavenging devices are already widely deployed. For instance, the Square point-of-sale reader uses the microphone/speaker interface of a smartphone for communications and as power supply. While such devices are used as trusted devices in security critical applications in the wild, they have not been properly evaluated yet. $μ$Leech can securely store keys and provide cryptographic services to any connected smart phone. Our design also facilitates physical security analysis by providing interfaces to facilitate acquisition of power traces and clock manipulation attacks. Thus $μ$Leech empowers security researchers to analyze leakage in next generation embedded and IoT devices and to evaluate countermeasures before deployment.

Mohagheghi, S..  2014.  Integrity Assessment Scheme for Situational Awareness in Utility Automation Systems. Smart Grid, IEEE Transactions on. 5:592-601.

Today's more reliable communication technology, together with the availability of higher computational power, have paved the way for introduction of more advanced automation systems based on distributed intelligence and multi-agent technology. However, abundance of data, while making these systems more powerful, can at the same time act as their biggest vulnerability. In a web of interconnected devices and components functioning within an automation framework, potential impact of malfunction in a single device, either through internal failure or external damage/intrusion, may lead to detrimental side-effects spread across the whole underlying system. The potentially large number of devices, along with their inherent interrelations and interdependencies, may hinder the ability of human operators to interpret events, identify their scope of impact and take remedial actions if necessary. Through utilization of the concepts of graph-theoretic fuzzy cognitive maps (FCM) and expert systems, this paper puts forth a solution that is able to reveal weak links and vulnerabilities of an automation system, should it become exposed to partial internal failure or external damage. A case study has been performed on the IEEE 34-bus test distribution system to show the efficiency of the proposed scheme.