@article{MTMT:34761133,
	title = {Recent Advances of VO2 in Sensors and Actuators},
	url = {https://m2.mtmt.hu/api/publication/34761133},
	author = {Darwish, Mahmoud Ibrahim Azmi and Zhabura, Yana and Pohl, László},
	doi = {10.3390/nano14070582},
	journal-iso = {NANOMATERIALS-BASEL},
	journal = {NANOMATERIALS},
	volume = {14},
	unique-id = {34761133},
	abstract = {Vanadium dioxide (VO2) stands out for its versatility in numerous applications, thanks to its unique reversible insulator-to-metal phase transition. This transition can be initiated by various stimuli, leading to significant alterations in the material’s characteristics, including its resistivity and optical properties. As the interest in the material is growing year by year, the purpose of this review is to explore the trends and current state of progress on some of the applications proposed for VO2 in the field of sensors and actuators using literature review methods. Some key applications identified are resistive sensors such as strain, temperature, light, gas concentration, and thermal fluid flow sensors for microfluidics and mechanical microactuators. Several critical challenges have been recognized in the field, including the expanded investigation of VO2-based applications across multiple domains, exploring various methods to enhance device performance such as modifying the phase transition temperature, advancing the fabrication techniques for VO2 structures, and developing innovative modelling approaches. Current research in the field shows a variety of different sensors, actuators, and material combinations, leading to different sensor and actuator performance input ranges and output sensitivities.},
	year = {2024},
	eissn = {2079-4991},
	orcid-numbers = {Pohl, László/0000-0003-2390-1381}
}

@article{MTMT:34681240,
	title = {Insulator Metal Transition-Based Selector in Crossbar Memory Arrays},
	url = {https://m2.mtmt.hu/api/publication/34681240},
	author = {Darwish, Mahmoud Ibrahim Azmi and Pohl, László},
	doi = {10.3390/electronicmat5010002},
	journal-iso = {ELECTRON MATER},
	journal = {ELECTRONIC MATERIALS},
	volume = {5},
	unique-id = {34681240},
	abstract = {This article investigates resistive random access memory (ReRAM) crossbar memory arrays, which is a notable development in non-volatile memory technology. We highlight ReRAM’s competitive edge over NAND, NOR Flash, and phase-change memory (PCM), particularly in terms of endurance, speed, and energy efficiency. This paper focuses on the architecture of crossbar arrays, where memristive devices are positioned at intersecting metal wires. We emphasize the unique resistive switching mechanisms of memristors and the challenges of sneak path currents and delve into the roles and configurations of selectors, particularly focusing on the one-selector one-resistor (1S1R) architecture with an insulator–metal transition (IMT) based selector. We use SPICE simulations based on defined models to examine a 3 × 3 1S1R ReRAM array with vanadium dioxide selectors and titanium dioxide film memristors, assessing the impact of ambient temperature and critical IMT temperatures on array performance. We highlight the operational regions of low resistive state (LRS) and high resistive state (HRS), providing insights into the electrical behavior of these components under various conditions. Lastly, we demonstrate the impact of selector presence on sneak path currents. This research contributes to the overall understanding of ReRAM crossbar arrays integrated with IMT material-based selectors.},
	year = {2024},
	eissn = {2673-3978},
	pages = {17-29},
	orcid-numbers = {Pohl, László/0000-0003-2390-1381}
}

@inproceedings{MTMT:34448278,
	title = {HexMG: A Circuit-Model Based Finite Multi-Domain Simulator},
	url = {https://m2.mtmt.hu/api/publication/34448278},
	author = {Pohl, László},
	booktitle = {2023 29th International Workshop on Thermal Investigations of ICs and Systems (THERMINIC)},
	doi = {10.1109/THERMINIC60375.2023.10325907},
	unique-id = {34448278},
	abstract = {This paper presents a new open-source simulator that aims to provide a tool to study a wide range of current and future problems requiring high-resolution distributed simula tion in engineering practice, especially in microelectronics. The problem to be studied is defined as a circuit model, which can be specified by a SPICE-like description. The simulator solves this circuit using the highly efficient Successive Network Reduction Method, optimized specifically for solving circuit models of fields discretized by the Finite Differences or Finite Volumes methods. The circuits can be extended with programmable special components: controllers, to easily implement special tasks such as hysteresis or ray tracing modelling. © 2023 IEEE.},
	keywords = {MICROELECTRONICS; Engineering practices; High resolution; Model-based OPC; spice; circuit simulation; DISTRIBUTED SIMULATION; Circuit modeling; FDM; Frequency division multiplexing; Open-source; Timing circuits; Distributed simulations; 'current; FVM; FVM; Multi-domains; Network reduction method},
	year = {2023},
	orcid-numbers = {Pohl, László/0000-0003-2390-1381}
}

@inproceedings{MTMT:34448274,
	title = {SPICE Modeling of Insulator-Metal Transition Devices with Hysteresis},
	url = {https://m2.mtmt.hu/api/publication/34448274},
	author = {Darwish, Mahmoud Ibrahim Azmi and Pohl, László},
	booktitle = {2023 29th International Workshop on Thermal Investigations of ICs and Systems (THERMINIC)},
	doi = {10.1109/THERMINIC60375.2023.10325868},
	unique-id = {34448274},
	abstract = {A New SPICE model for insulator-metal transition (IMT) devices is presented in this paper. The combined influences of the electric field and Joule heating are considered, allowing a transition from the high-resistance monoclinic phase to the low-resistance metallic one. Hysteresis, observed in specific IMT materials such as vanadium dioxide, is effectively addressed. The model's accuracy was validated using experimental results and electro-thermal FVM simulations. It has been implemented in VHDL-AMS, ensuring its compatibility with SPICE simulators like Xpedition AMS and PartQuest Explore, which were employed in this research. The model characterizes three specific device states, heating, cooling, and equilibrium. Transition dynamics between these states are tied to historical temperature data, represented as the device's temperature time derivative. To our knowledge, this model is the first IMT compact model that addresses hysteresis and is the first VHDL-AMS for IMT devices. With this development, circuit designers are provided with tools to fully explore the potential of VO2 and similar IMT devices to design and realize next-generation electrical circuits. © 2023 IEEE.},
	keywords = {hysteresis; Electric fields; Semiconductor insulator boundaries; Metal insulator boundaries; Metal insulator transition; IMT; spice; spice; Compact model; Compact model; VO2; insulator-metal transition; monoclinic phase; vanadium dioxide; 'spice'; Low resistance; Joules heating; High resistance; Insulator metal transition; VHDL-AMS; VHDL-AMS; SPICE modeling},
	year = {2023},
	orcid-numbers = {Pohl, László/0000-0003-2390-1381}
}

@inproceedings{MTMT:32236564,
	title = {Application of Vanadium Dioxide for Thermal Sensing},
	url = {https://m2.mtmt.hu/api/publication/32236564},
	author = {Darwish, Mahmoud Ibrahim Azmi and Al-abassi, Salam and Neumann, Péter Lajos and Mizsei, János and Pohl, László},
	booktitle = {Proceedings of the 27th International Workshop on THERMal INvestigations of ICs and Systems (THERMINIC'21 online)},
	doi = {10.1109/THERMINIC52472.2021.9626518},
	unique-id = {32236564},
	abstract = {Thermal sensors are widely used in different areas such as, automotive, defense, healthcare, and fire protection. Heat management is a hot topic nowadays, especially in electronics and power electronic packages, due to the miniaturization of semiconductor devices dimensions. New materials and concepts are studied to develop thermal sensors with more excellent reliability and sensitivity. Vanadium dioxide is a strongly correlated electron material with interesting thermal and optical properties due to its transition from a low-conducting phase to a high-conducting phase called metal-to-insulator transition. This study investigates two different models to use vanadium dioxide as a sensing element by presenting simulations performed on SUNRED simulator.},
	year = {2021},
	pages = {249-252},
	orcid-numbers = {Neumann, Péter Lajos/0000-0002-2881-5733; Mizsei, János/0000-0003-3411-1502; Pohl, László/0000-0003-2390-1381}
}

@inproceedings{MTMT:32236558,
	title = {Comparative multiphysics simulation of VO2 based lateral devices},
	url = {https://m2.mtmt.hu/api/publication/32236558},
	author = {Al-abassi, Salam and Darwish, Mahmoud Ibrahim Azmi and Pohl, László and Mizsei, János and Neumann, Péter Lajos},
	booktitle = {Proceedings of the 27th International Workshop on THERMal INvestigations of ICs and Systems (THERMINIC'21 online)},
	doi = {10.1109/THERMINIC52472.2021.9626517},
	unique-id = {32236558},
	abstract = {Due to reaching the end of Moore’s era and minimising CMOS technology becomes difficult. Finding different materials to keep electronic devices evolving is a matter of scientists. A thermal electronic logic circuit (TELC) is one of the most prominent alternatives that has been proposed recently. Vanadium dioxide (VO2) is an essential material that has been utilised in TELC due to its thermal and electrical properties. VO2 transits its electrical property from the semiconductor phase into the metal phase at around 67oC. In this paper, two numerical methods were used to determine the electrical and thermal characteristics of VO2, and measured data compared the results. The phase-change material behaviour was modelled by two different softwares using different simulation methods, finite volume method FVM and finite element method FEM. The sample preparation and the thermal and electrical measurements were carried out in our cleanroom.},
	year = {2021},
	pages = {178-181},
	orcid-numbers = {Pohl, László/0000-0003-2390-1381; Mizsei, János/0000-0003-3411-1502; Neumann, Péter Lajos/0000-0002-2881-5733}
}

@inproceedings{MTMT:31778148,
	title = {Study of Dynamic Simulation for Thermal-Electronic Logic Circuits},
	url = {https://m2.mtmt.hu/api/publication/31778148},
	author = {Darwish, Mahmoud Ibrahim Azmi and Neumann, Péter Lajos and Mizsei, János and Pohl, László},
	booktitle = {Proceedings of the 26th International Workshop on THERMal INvestigations of ICs and Systems (THERMINIC)},
	doi = {10.1109/THERMINIC49743.2020.9420495},
	unique-id = {31778148},
	abstract = {Emerging devices and materials in computing industry are recently of great interest because classical silicon-based circuit development is saturating due to scaling limits. Thermal-electronic logic circuit (TELC) concept is a promising approach to enhance conventional CMOS circuits or even replace them. Semiconductor-to-metal transition (SMT) of vanadium dioxide (VO2) is the main part of TELC as it allows transmission and control of information flow both electrically and thermally. The first TELC inverter is introduced in this article, dynamic simulations are performed to test its behavior and relation between propagation delay and input voltage is demonstrated. A new phase transition model is used to upgrade our SUNRED simulator. This new version is accurate and proved to be suitable for dynamic simulations. This article presents first dynamic simulation of SMT material.},
	year = {2020},
	pages = {97-102},
	orcid-numbers = {Neumann, Péter Lajos/0000-0002-2881-5733; Mizsei, János/0000-0003-3411-1502; Pohl, László/0000-0003-2390-1381}
}

@article{MTMT:31395925,
	title = {Mixed Detailed and Compact Multi-Domain Modeling to Describe CoB LEDs},
	url = {https://m2.mtmt.hu/api/publication/31395925},
	author = {Pohl, László and Hantos, Gusztáv and Hegedüs, János and Németh, Márton and Kohári, Zsolt and Poppe, András},
	doi = {10.3390/en13164051},
	journal-iso = {ENERGIES},
	journal = {ENERGIES},
	volume = {13},
	unique-id = {31395925},
	issn = {1996-1073},
	abstract = {Large area multi-chip LED devices, such as chip-on-board (CoB) LEDs, require the combined use of chip-level multi-domain compact LED models (Spice-like compact models) and the proper description of distributed nature of the thermal environment (the CoB substrate and phosphor) of the LED chips. In this paper, we describe such a new numerical solver that was specifically developed for this purpose. For chip-level, the multi-domain compact modeling approach of the Delphi4LED project is used. This chip-level model is coupled to a finite difference scheme based numerical solver that is used to simulate the thermal phenomena in the substrate and in the phosphor (heat transfer and heat generation). Besides solving the 3D heat-conduction problem, this new numerical simulator also tracks the propagation and absorption of the blue light emitted by the LED chips, as well as the propagation and absorption of the longer wavelength light that is converted by the phosphor from blue. Heat generation in the phosphor, due to conversion loss (Stokes shift), is also modeled. To validate our proposed multi-domain model of the phosphor, dedicated phosphor and LED package samples with known resin—phosphor powder ratios and known geometry were created. These samples were partly used to identify the nature of the temperature dependence of phosphor-conversion efficiency and were also used as simple test cases to “calibrate” and test the new numerical solver. With the models developed, combined simulation of the LED chip and the CoB substrate + phosphor for a known CoB LED device is shown, and the simulation results are compared to measurement results.},
	year = {2020},
	eissn = {1996-1073},
	orcid-numbers = {Pohl, László/0000-0003-2390-1381; Hantos, Gusztáv/0000-0002-0401-2098; Hegedüs, János/0000-0003-4792-6225; Németh, Márton/0000-0002-3517-5359; Kohári, Zsolt/0000-0002-9908-6291; Poppe, András/0000-0002-9381-6716}
}

@article{MTMT:31369246,
	title = {Electro-Thermal Simulation of Vertical VO2 Thermal-Electronic Circuit Elements},
	url = {https://m2.mtmt.hu/api/publication/31369246},
	author = {Darwish, Mahmoud Ibrahim Azmi and Neumann, Péter Lajos and Mizsei, János and Pohl, László},
	doi = {10.3390/en13133447},
	journal-iso = {ENERGIES},
	journal = {ENERGIES},
	volume = {13},
	unique-id = {31369246},
	issn = {1996-1073},
	abstract = {Advancement of classical silicon-based circuit technology is approaching maturity and saturation. The worldwide research is now focusing wide range of potential technologies for the “More than Moore” era. One of these technologies is thermal-electronic logic circuits based on the semiconductor-to-metal phase transition of vanadium dioxide, a possible future logic circuits to replace the conventional circuits. In thermal-electronic circuits, information flows in a combination of thermal and electronic signals. Design of these circuits will be possible once appropriate device models become available. Characteristics of vanadium dioxide are under research by preparing structures in laboratory and their validation by simulation models. Modeling and simulation of these devices is challenging due to several nonlinearities, discussed in this article. Introduction of custom finite volumes method simulator has however improved handling of special properties of vanadium dioxide. This paper presents modeling and electro-thermal simulation of vertically structured devices of different dimensions, 10 nm to 300 nm layer thicknesses and 200 nm to 30 um radii. Results of this research will facilitate determination of sample sizes in the next phase of device modeling.},
	year = {2020},
	eissn = {1996-1073},
	orcid-numbers = {Neumann, Péter Lajos/0000-0002-2881-5733; Mizsei, János/0000-0003-3411-1502; Pohl, László/0000-0003-2390-1381}
}

@article{MTMT:31028059,
	title = {Integrated Thermal Management in System-on-Package Devices},
	url = {https://m2.mtmt.hu/api/publication/31028059},
	author = {Bognár, György and Takács, Gábor and Szabó, Péter Gábor and Rózsás, Gábor and Pohl, László and Plesz, Balázs},
	doi = {10.3311/PPee.14986},
	journal-iso = {PERIOD POLYTECH ELECTR ENG COMP SCI},
	journal = {PERIODICA POLYTECHNICA-ELECTRICAL ENGINEERING AND COMPUTER SCIENCE},
	volume = {64},
	unique-id = {31028059},
	issn = {2064-5260},
	abstract = {Thanks to the System-on-Package technology (SoP) the integration of different elements into a single package was enabled. However, from the thermal point of view the heat removal path in modern packaging technologies (FCBGA) goes through several layers of thermal interface material (TIM) that together with the package material create a relatively high thermal resistance which may lead to elevated chip temperature which causes functional error or other malfunctions. In our concept, we overcome this problem by creating integrated microfluidic channel based heat sink structures that can be used for cooling the high heat dissipation semiconductor devices (e.g.: processors, high power transistor or concentrated solar cells). These microchannel cooling assemblies can be integrated into the backside of the substrate of the semiconductor devices or into the system assemblies in SoP technology. In addition to the realization of the novel CMOS compatible microscale cooling device we have developed precise and valid measurement methodology, simulation cases studies and a unique compact model that can be added to numerical simulators as an external node. In this paper the achievements of a larger research are summarized as it required the cooperation of several experts in their fields to fulfil the goal of creating a state-of-the-art demonstrator.},
	year = {2020},
	eissn = {2064-5279},
	pages = {200-210},
	orcid-numbers = {Bognár, György/0000-0003-4582-3900; Takács, Gábor/0000-0001-8081-1169; Szabó, Péter Gábor/0000-0001-7601-743X; Pohl, László/0000-0003-2390-1381}
}