Microelectronic Engineering最新文献

{"title":"Design of memristor hyperchaotic circuit with burst oscillation and infinite attractor coexistence and its application","authors":"Jie Zhang,&nbsp;Yan Guo,&nbsp;Jinhao Guo","doi":"10.1016/j.mee.2023.112099","DOIUrl":"https://doi.org/10.1016/j.mee.2023.112099","url":null,"abstract":"<div><p><span><span><span>A 4D hyperchaotic system with symmetry based on memristors is proposed and the chaotic properties of the circuit are verified by </span>phase diagrams, Poincaré cross sections, bifurcation, </span>Lyapunov exponents<span>, and 0–1 tests. In addition, the system is found to have rich dynamical behaviors<span> such as transient chaos, intermittent chaos, offset enhancement, burst oscillation, and infinite attractor coexistence. The complexity comparison analysis reveals that this hyperchaotic system has good symmetry as well as the initial values of the system that are more suitable for image encryption. Circuit simulation of the system using simulation software proved the usability of the system. A </span></span></span>field programmable gate array<span> (FPGA) is used to implement the actual digital circuit<span> of the system. The final FPGA results agree with the numerical simulation and prove the practical value of the constructed memristor hyperchaotic system. Finally, chaotic circuits are applied to DNA image encryption. It is discovered to have a very large key space, strong key sensitivity, outstanding anti-cropping, noise immunity and high security performance. Thus, the proposed hyperchaotic system has good advantages for application in the field of image encryption.</span></span></p></div>","PeriodicalId":18557,"journal":{"name":"Microelectronic Engineering","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49724121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High consistency VO2 memristor for artificial auditory neuron","authors":"Yan Wang ,&nbsp;Chaohui Su ,&nbsp;Yiming Zheng ,&nbsp;Kexin Zhou ,&nbsp;Zhenli Wen ,&nbsp;Yujun Fu ,&nbsp;Qi Wang ,&nbsp;Deyan He","doi":"10.1016/j.mee.2023.112101","DOIUrl":"https://doi.org/10.1016/j.mee.2023.112101","url":null,"abstract":"<div><p><span><span>With scalability and diverse device behavior, memristors present potential for executing neuromorphic computation with lower hardware cost and </span>power consumption. However, Low consistency currently limited the application of memristors. Herein, we report a VO</span>₂<span>-based memristor fabricated through magnetron<span> sputtering and multiple annealing processes<span>, exhibiting extremely low in both cycle-to-cycle (C2C) and device-to-device (D2D) variations. Further, a Hodgkin-Huxley model neuron circuit based on the extremely high consistency of the devices is established, which achieves auditory neuron perception simulation through spatiotemporal processing of spike signals, allowing for clear differentiation of sound source direction and displaying patterns akin to biological behavior. This easily implemented and highly consistent artificial neuron offers a promising approach for the development of next-generation artificial auditory systems.</span></span></span></p></div>","PeriodicalId":18557,"journal":{"name":"Microelectronic Engineering","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49737590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SAR assessment of miniaturized wideband MIMO antenna structure for millimeter wave 5G smartphones","authors":"Rania Hamdy Elabd ,&nbsp;Ahmed Jamal Abdullah Al-Gburi","doi":"10.1016/j.mee.2023.112098","DOIUrl":"https://doi.org/10.1016/j.mee.2023.112098","url":null,"abstract":"<div><p><span><span>This work introduces a wideband two-element Multiple-Input Multiple-Output (MIMO) antenna array that covers the desired frequencies of 28/38 GHz for millimeter-wave (mmW) </span>5G<span> smartphones. The antenna array demonstrates significant isolation and gain increase based on dual-mode planar dipole antennas. The proposed structure was designed using CST Microwave Studio 2019. The design is implemented on a Rogers RT 4003 substrate measuring 14.76 × 8.38 mm</span></span>²<span><span><span> with a dielectric constant of 3.55. It features two planar dipole antennas positioned at the corners in a perpendicular arrangement to each other. To achieve the desired wideband performance, each element consists of a dipole antenna and a partial ground plane. The spacing between elements, including the parasitic element<span> (PE), is set to 0.5λ₀ to increase isolation between the MIMO antenna elements while keeping complexity and cost to a minimum. Simulation results demonstrate an improvement in mutual coupling between array members, with measured values ranging from −55 dB to −75 dB. The envelope </span></span>correlation coefficient (ECC) is also improved. Furthermore, enhancements are observed in the total active </span>reflection coefficient<span> (TARC), mean effective gain (MEG), and diversity gain (DG). The measured gains of the proposed designs range from 6 dBi across the entire band to 10 dBi at 40 GHz, with a radiation efficiency close to 95%. The antenna performs well in the presence of the handset and human head model during simulation. The study identifies a safe and acceptable specific absorption rate (SAR) value, which provides a low SAR10g of about 0.963 W/Kg at 28 GHz and 0.583 W/Kg at 38 GHz. while maintaining superior efficiency and radiation patterns. When the antennas are constructed and tested, the experimental results surpass the modeling results. The simulation and test findings demonstrate a satisfactory fit within the target band, suggesting that the proposed structure could be applied to millimeter-wave 5G smartphones.</span></span></p></div>","PeriodicalId":18557,"journal":{"name":"Microelectronic Engineering","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49737589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High aspect-ratio sub-500 nm UV-PDMS bilayer stamps by means of hybrid thermal-ultraviolet curing for resonant nanopillars fabrication through soft UV-NIL","authors":"Luca Tramarin ,&nbsp;Rafael Casquel ,&nbsp;Iñigo Mañueco ,&nbsp;Miguel Holgado","doi":"10.1016/j.mee.2023.112088","DOIUrl":"10.1016/j.mee.2023.112088","url":null,"abstract":"<div><p><span>A novel protocol for the fabrication of bilayer stamps for soft UV-NIL is presented. The patterned layer is composed of a commercially available UV-curable PDMS, while a quartz backplane acts as support layer. The pattern reproduced in the stamp through direct casting comes from a hard template and is composed of </span>nanopillar<span> arrays with 250–300 nm of diameter and 300–400 nm in height. The master template with nanoholes is treated with a self-assembled monolayer before pattern reproduction for improved separation of UV-PDMS layer. The hybrid cross-linking protocol includes a thermal and a UV process, and parameters of the former are investigated for best results. The pattern was reproduced in a resist on a Si sample by means of soft UV-NIL, and the imprinted nanohole arrays show dimensions coherent with the stamp. Finally, its application in the fabrication of resonant nanopillars for sensing purposes is briefly described. This is, to the best of our knowledge, the first time a hybrid thermal-ultraviolet curing of UV-PDMS has been reported and that protruding nanostructures with aspect-ratio higher than 1 in soft UV-NIL stamps have been demonstrated.</span></p></div>","PeriodicalId":18557,"journal":{"name":"Microelectronic Engineering","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48593289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"8 A, 200 V normally-off cascode GaN-on-Si HEMT: From epitaxy to double pulse testing","authors":"Rijo Baby ,&nbsp;Manish Mandal ,&nbsp;Shamibrota K. Roy ,&nbsp;Abheek Bardhan ,&nbsp;Rangarajan Muralidharan ,&nbsp;Kaushik Basu ,&nbsp;Srinivasan Raghavan ,&nbsp;Digbijoy N. Nath","doi":"10.1016/j.mee.2023.112085","DOIUrl":"10.1016/j.mee.2023.112085","url":null,"abstract":"<div><p><span><span>In this paper, we provide a comprehensive study on all aspects of development of normally-off multi-finger III-nitride HEMT on </span>Silicon<span> in cascode configuration. AlGaN/GaN HEMT epi-stack with in situ SiN cap was grown on 2-in. Silicon (111) using MOCVD<span><span><span>, utilizing a 2-step AlN nucleation, step-graded AlGaN transition layer and C-doped GaN buffer. Depletion-mode HEMTs in winding gate geometry with a gate width of 30 mm were fabricated with thick electroplated metal contacts and an optimized bilayer SiN </span>passivation<span>. Devices were diced and packaged in TO254 with conducting epoxy and Au-coated ceramic substrate. These packaged D-mode HEMTs exhibited a </span></span>threshold voltage (V</span></span></span>_th<span>) of −12 V, maximum ON current of 10 A, and a 3-terminal hard breakdown in excess of 400 V. Bare dies of D-mode HEMTs were then integrated with commercially procured silicon MOSFET in a TO254 package in cascode configuration to achieve V</span>_th &gt; 2 V, ON current of 8 A, and breakdown &gt;200 V. The normally-off cascaded GaN HEMTs were subjected to various gate and drain stress measurements and were found to exhibit a V_th<span><span> shift of 10 mV after 1000 s of positive gate (+5 V) stress. The input and output capacitances of the cascode devices were measured to be 1 nF and 0.8 nF, respectively. The 3rd quadrant operation was checked at 8 A on-state current level to reveal a lower voltage drop of 0.7 V. Finally, cascode HEMTs were subjected to double pulsed testing (DPT) using a half-bridge evaluation board. On and off rise times of 52 ns and 59 ns were obtained along with </span>energy loss of 25 μJ and 20 μJ, respectively, for devices switched at 8 A, 100 V.</span></p></div>","PeriodicalId":18557,"journal":{"name":"Microelectronic Engineering","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49547040","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Flexible pressure sensor with wide pressure range based on 3D microporous PDMS/MWCNTs for human motion detection","authors":"Chun-Sheng Jiang,&nbsp;Ru-Yue Lv,&nbsp;Yan-Li Zou,&nbsp;Hui-Ling Peng","doi":"10.1016/j.mee.2023.112105","DOIUrl":"https://doi.org/10.1016/j.mee.2023.112105","url":null,"abstract":"<div><p><span><span>Introducing microstructure in the flexible pressure sensors is an effective strategy to enhance the performance of the sensor. Herein, we fabricated a flexible pressure sensor with three-dimensional (3D) miroporous based on a hybrid of </span>polydimethylsiloxane<span> (PDMS) and multiwalled carbon nanotubes (MWCNTs). The 3D microporous was produced by a facile and low-cost process using NH</span></span>₄HCO₃ as a sacrificial template, the NH₄HCO₃<span> particles were decomposed to gas<span> and left microporous in the hybrid of PDMS and MWCNTs. The microporous structure inside the sensor allowed for a wide pressure range (∼140 kPa). The sensor could detect large motions of finger, wrist, elbow, knee, and even small motion such as facial expression. In addition, a 3 × 3 tactile sensor<span> array was successfully applied in the pressure distribution of fingers to grasp a cup. The results demonstrate that the sensor is promising application in wearable electronics and human-machine interfaces for pressure sensing.</span></span></span></p></div>","PeriodicalId":18557,"journal":{"name":"Microelectronic Engineering","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49726851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preventing oxide precipitation in selective wet etching of Si3N4 for 3D-NAND structure fabrication: The role of bubbles","authors":"Hao Zhang ,&nbsp;Haiqiang Yang ,&nbsp;Fang Yuan,&nbsp;Bo Liu,&nbsp;Qiang Yang","doi":"10.1016/j.mee.2023.112104","DOIUrl":"https://doi.org/10.1016/j.mee.2023.112104","url":null,"abstract":"<div><p>Selective wet etching of <span><math><msub><mi>Si</mi><mn>3</mn></msub><msub><mi>N</mi><mn>4</mn></msub></math></span> is a critical process in the fabrication of 3D-NAND structures; however, it faces a oxide precipitation problem that significantly deteriorates the remaining structure morphology. A recent study by Kim et al.(Kim et al., 2022 [<span>1</span>]⁾ showed that generating CO₂<span><span> bubbles during the wet etching process efficiently solves the precipitation problem in the fabrication of a 128 multi-layer 3D-NAND structure. In this study, we numerically investigated the multiscale diffusive transport<span> of oxides in the etching process via three different simplified simulations at different scales to reveal the underlying mechanism. We found that mass transport within the multilayer structures alone cannot contribute to the oxide </span></span>precipitation behavior. Macroscopic transport from the wafer-etchant interface to the bulk must be considered since it contributes to a high oxide concentration at the wafer-etchant surface, which further increases the concentration within the trenches, leading to the precipitation problem. Through the conjecture oxide transport simulation, we found that the large bubbles generated from the reaction agitate the surrounding liquid and dramatically reduce the oxide concentration at the wafer-etchant surface by one order of magnitude, thereby solving the precipitation problem. Our findings clearly explain the experimental results reported by Kim et al. and will further benefit the development of process-intensification technologies in wet etching.</span></p></div>","PeriodicalId":18557,"journal":{"name":"Microelectronic Engineering","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49726615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structural and electrical correlation in aluminum nitride thin films grown by plasma enhanced atomic layer deposition as interface insulating layers on silicon carbide (4H-SiC)","authors":"Bruno Galizia ,&nbsp;Patrick Fiorenza ,&nbsp;Corrado Bongiorno ,&nbsp;Béla Pécz ,&nbsp;Zsolt Fogarassy ,&nbsp;Emanuela Schilirò ,&nbsp;Filippo Giannazzo ,&nbsp;Fabrizio Roccaforte ,&nbsp;Raffaella Lo Nigro","doi":"10.1016/j.mee.2023.112103","DOIUrl":"https://doi.org/10.1016/j.mee.2023.112103","url":null,"abstract":"<div><p><span><span>(0001) oriented aluminum </span>nitride<span><span> (AlN) thin films have been grown by plasma enhanced </span>atomic layer deposition<span> (PE-ALD) on silicon carbide (4H-SiC) substrates. During different PE-ALD processes, the ammonia (NH</span></span></span>₃<span>) plasma pulsing time has been varied and its effect on the microstructure and on the orientation degree of the AlN layers has been monitored. Structural characterization by Transmission Electron Microscopy (TEM) showed that the crystalline structure of the deposited films was strongly dependent on the NH</span>₃<span>-plasma pulsing, so that different polymorphic structures were observed. In particular, both processes resulted in wurtzite<span> AlN structure for few nanometers at the interface with the 4H-SiC substrate, while upon increasing thickness a poly-crystalline wurtzite phase was obtained by short-pulse NH</span></span>₃<span>-plasma, whereas longer plasma exposure resulted in a mixture of wurtzite and zincblende defective phases. Phase formation mechanism were discussed and electrical nanoscopic characterization by conductive atomic force microscopy<span> showed a clear correlation between the different AlN crystalline phases and the insulating properties.</span></span></p></div>","PeriodicalId":18557,"journal":{"name":"Microelectronic Engineering","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49738206","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Few layer chemical vapor deposited two dimensional WS2 for low voltage resistive switching application","authors":"Awais Khalid ,&nbsp;Pervaiz Ahmad ,&nbsp;Ahmad M. Saeedi ,&nbsp;Iram Liaqat ,&nbsp;N.S. Abd EL-Gawaad ,&nbsp;Sahar Ahmed Idris ,&nbsp;Abdulaziz M. Alanazi ,&nbsp;Amal H. Alsehli ,&nbsp;Marwah M. Alsowayigh ,&nbsp;Suliman A. Alderhami","doi":"10.1016/j.mee.2023.112083","DOIUrl":"10.1016/j.mee.2023.112083","url":null,"abstract":"<div><p><span>Optimizing the fabrication method gives rise to control over the deposition of WS</span>₂<span><span> sheets in a CVD chamber. The deposition was executed on Pt-coated </span>silicon substrate so that electrical behavior of the WS</span>₂<span> domains could be observed. Utilizing two types of electrode material helped in understanding the role of metal diffusion mediated switching failure. The Au/WS</span>₂/Pt/Ti/SiO₂<span>/Si device exhibited resistive switching characteristics at very low operating voltages. A high on/off ratio (&gt;10</span>⁴), high retention time (10⁴ s), and a long endurance (1500 cycles) were respectively recorded to establish the non-volatile memory characteristics in a device with thin layer of WS₂<span><span>. The switching mechanism was established by performing conducting atomic force microscopy. This work also explained the mechanism of resistance switching in CVD grown </span>tungsten disulfide in two steps and pave the way for the development of large-scale devices.</span></p></div>","PeriodicalId":18557,"journal":{"name":"Microelectronic Engineering","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42745966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thick film MEMS process using reverse lift-off","authors":"S. Takase,&nbsp;K. Yamada,&nbsp;Y. Nakagawa,&nbsp;C. Oka,&nbsp;J. Sakurai,&nbsp;S. Hata","doi":"10.1016/j.mee.2023.112081","DOIUrl":"10.1016/j.mee.2023.112081","url":null,"abstract":"<div><p>The lift-off process is a microfabrication technique that has the capability of forming thin film structures. However, several issues, such as structural shape and burr formation, arise when applying this method to the formation of thick film structures. Thick film structures formed through the lift-off process exhibit a mountainous cross-sectional shape and non-uniform film thickness due to variations in the width of the structure. These challenges make it difficult to apply the method to MEMS. While the reverse lift-off process addresses some of the structural shape problems, its initial development using metal molds makes it challenging to directly apply to MEMS without modification. Therefore, this paper proposes an adaptation to the Si process and presents a method to reduce burrs. The microfabrication characteristics are evaluated by comparing the cross-sectional shapes of thick metallic glass structures formed through both the lift-off and reverse lift-off processes. The structures formed through the reverse lift-off process exhibit a rectangular cross-sectional shape, and the film thickness remains consistent regardless of the structure's width. However, burrs persist on the backside edge of the structure, which hinders its application to MEMS. This paper confirms that pre-etching the underlying Si substrate into an inverse tapered shape effectively reduces burrs. As an illustration of the improved reverse lift-off process applied to MEMS, MEMS mirror structures are fabricated, and their resonance frequency closely aligns with the design value.</p></div>","PeriodicalId":18557,"journal":{"name":"Microelectronic Engineering","volume":null,"pages":null},"PeriodicalIF":2.3,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48671861","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}