Journal of Vacuum Science & Technology. B. Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phenomena最新文献_第4页

Pyroelectric lithium niobate electron emission-based ion-pump 热释电铌酸锂电子发射离子泵

Journal of Vacuum Science & Technology. B. Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phenomena Pub Date : 2021-03-17 DOI: 10.1116/6.0000882

K. Vinayakumar, V. Gund, A. Lal

{"title":"Pyroelectric lithium niobate electron emission-based ion-pump","authors":"K. Vinayakumar, V. Gund, A. Lal","doi":"10.1116/6.0000882","DOIUrl":"https://doi.org/10.1116/6.0000882","url":null,"abstract":"This work presents a compact ion-pump that utilizes pyroelectricity for ionization of ambient molecules. The pyroelectric ionization is realized by heating a lithium niobate (LiNbO3) crystal with low voltage resistive heating (10 V drive voltage, 0.5 W Joule heating) to generate a high voltage across the poled surface of the crystal. Pyroelectrically generated electrons from the polarized surface of the crystal are accelerated using an electric field generated by both the crystal and external titanium (Ti) electrodes biased at ±300 V, which results in the ionization of molecules in the chamber. The low collector current in the pA range ensures that the power consumed due to ionization current is lower than the LiNbO3 heating power. The ionized gas molecules are accelerated toward the Ti collector electrodes where they are implanted owing to large acceleration produced by the collector electrodes. The system is configured as a sputter pump for gettering ions to reduce chamber pressure from the baseline value of 1.4 μTorr with just the external pump to 1.1 μTorr by incorporating the LiNbO3 pump. The proof-of-concept of the pyroelectric pumping mechanism is demonstrated using a 140 cm3 stainless steel vacuum chamber, with supplementary turbomolecular and diaphragm pumps and demonstrates that a 50 s thermal cycling of the crystal is optimal for the ion-pump. Pumping action was measured with a Pirani gauge and a hot cathode ion gauge. Analytical modeling and experimental results for pumping speed calculations showed a good match during high-pressure pumping.","PeriodicalId":17652,"journal":{"name":"Journal of Vacuum Science & Technology. B. Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phenomena","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79327636","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

High sensitivity x-ray detectors based on 4H-SiC p-i-n structure with 80 μm thick intrinsic layer 基于80 μm厚本征层4H-SiC p-i-n结构的高灵敏度x射线探测器

Journal of Vacuum Science & Technology. B. Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phenomena Pub Date : 2021-03-11 DOI: 10.1116/6.0000829

Qing Liu, Dong Zhou, Weizong Xu, Dunjun Chen, F. Ren, Rong Zhang, Youdou Zheng, Hai Lu

引用次数: 2

Theoretical model for fast calculations of the electrical resistivity of thin metallic films with rough surfaces 具有粗糙表面的金属薄膜电阻率快速计算的理论模型

Journal of Vacuum Science & Technology. B. Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phenomena Pub Date : 2021-02-24 DOI: 10.1116/6.0000781

A. A. Pribylov

引用次数: 1

Intrinsic excitation-dependent room-temperature internal quantum efficiency of AlGaN nanowires with varying Al contents 不同Al含量的AlGaN纳米线的本征激发相关室温内量子效率

Journal of Vacuum Science & Technology. B. Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phenomena Pub Date : 2021-02-23 DOI: 10.1116/6.0000763

Jiaying Lu, Y. Zhong, Songrui Zhao

{"title":"Intrinsic excitation-dependent room-temperature internal quantum efficiency of AlGaN nanowires with varying Al contents","authors":"Jiaying Lu, Y. Zhong, Songrui Zhao","doi":"10.1116/6.0000763","DOIUrl":"https://doi.org/10.1116/6.0000763","url":null,"abstract":"Aluminum gallium nitride (AlGaN) nanowires have become an emerging approach for semiconductor deep ultraviolet light-emitting devices. To further improve the device performance, it is critical to understand the optical quality of AlGaN nanowires. However, today, the room-temperature internal quantum efficiency (IQE) of AlGaN nanowires is predominantly analyzed by the temperature-dependent photoluminescence (PL) approach under one excitation power or taking the PL intensity ratio at the room temperature and low temperature with different excitation powers. In both cases, one needs to assume the low temperature IQE to be 100%, which is not always valid, in particular when the excitation power changes at the low temperature. In this work, we study the room-temperature IQE of AlGaN nanowires through the detailed excitation power-dependent PL experiments and theoretical analysis. This allows us to derive the intrinsic room-temperature IQE of AlGaN nanowires as a function of the excitation power. It is found that for an Al content in the range of 22%–54%, the IQE of all samples increases as the excitation increases, followed by an efficiency droop. Moreover, comparing different samples, the IQE at low excitations increases as the Al content increases, whereas the peak IQE reduces from 73% to 56% as the Al content increases. The underlying mechanisms are also discussed in this paper.","PeriodicalId":17652,"journal":{"name":"Journal of Vacuum Science & Technology. B. Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phenomena","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-02-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91201460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

About the robustness of Schottky conjecture when quasi-one-dimensional stages are present 关于准一维阶段存在时肖特基猜想的鲁棒性

Journal of Vacuum Science & Technology. B. Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phenomena Pub Date : 2021-02-17 DOI: 10.1116/6.0000727

Edgar Marcelino de Carvalho Neto

引用次数: 1

Formation of ideally ordered porous anodic zirconia by anodization of vacuum deposited Zr on molds 通过在模具上真空沉积锆的阳极氧化形成理想有序多孔阳极氧化锆

Journal of Vacuum Science & Technology. B. Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phenomena Pub Date : 2021-02-12 DOI: 10.1116/6.0000864

T. Kondo, Touko Tamura, T. Yanagishita, H. Masuda

引用次数: 1

Information extraction from Murphy–Good plots of tungsten field electron emitters 钨场电子发射体墨菲-古德曲线的信息提取

Journal of Vacuum Science & Technology. B. Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phenomena Pub Date : 2021-02-04 DOI: 10.1116/6.0000803

Mazen A. Madanat, Mohammad Al Share, Mohammad M. Allaham, M. Mousa

{"title":"Information extraction from Murphy–Good plots of tungsten field electron emitters","authors":"Mazen A. Madanat, Mohammad Al Share, Mohammad M. Allaham, M. Mousa","doi":"10.1116/6.0000803","DOIUrl":"https://doi.org/10.1116/6.0000803","url":null,"abstract":"This study introduces an easy methodology to test and analyze experimental field electron emission current-voltage data from metallic single-tip emitters; this novel and easy methodology is called the Murphy–Good plots. Tungsten electron emitters were used as an example and were prepared by the electrochemical etching process. The current-voltage characteristics are obtained in high vacuum levels and using a traditional field emission microscope. Murphy–Good plots are used to apply the well-known field electron emission orthodoxy test to the experimental data and then to extract the emitters’ characterization parameters if the test is passed. The novelty in using this type of plots lies in its independency on any correction factors, unlike the traditional Fowler–Nordheim and Millikan–Lauritsen plots, in addition to its simple theoretical form. The results are calculated using a simple web tool that applies the field electron emission orthodoxy test to any type of the current-voltage analysis plots and then to extract the characterization parameters of the emitters.","PeriodicalId":17652,"journal":{"name":"Journal of Vacuum Science & Technology. B. Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phenomena","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-02-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77677628","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Systematic growth of carbon nanotubes on aluminum substrate for enhanced field emission performance 在铝衬底上系统生长碳纳米管以增强场发射性能

Journal of Vacuum Science & Technology. B. Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phenomena Pub Date : 2021-02-03 DOI: 10.1116/6.0000560

P. Maity, S. Gandhi, Manuj Dixit, I. Lahiri

{"title":"Systematic growth of carbon nanotubes on aluminum substrate for enhanced field emission performance","authors":"P. Maity, S. Gandhi, Manuj Dixit, I. Lahiri","doi":"10.1116/6.0000560","DOIUrl":"https://doi.org/10.1116/6.0000560","url":null,"abstract":"For more than two decades, carbon nanotubes (CNTs) have shown great potential for a wide range of applications. Several methods are known to synthesize CNTs, though only a few of them are able to produce good quality and economically available CNTs. Chemical vapor deposition (CVD) is one of those methods that produce economically feasible and good quality CNTs onto specific substrates, even with nanopatterning. However, growing CNTs by CVD at temperatures below 700 °C remained a long-time challenge, as this meant keeping a host of low-melting materials out of bounds for direct CNT growth on them. In this work, CNTs have been synthesized directly onto a low-melting, conducting substrate, aluminum, by thermal CVD, at a temperature as low as 550 °C and up to as high as 650 °C (just below the melting point of aluminum). The diameters of the grown CNTs were observed to be influenced by process parameters, e.g., temperature and pressure. The effect of synthesis parameters on CNT diameters was verified by scanning electron microscopy and transmission electron microscopy. The quality of the CNTs was checked by Raman spectroscopy, selected area electron diffraction pattern of transmission electron microscopy, and XPS. It was observed that an increase in temperature and pressure had a significant effect on the diameters of the CNTs. Randomly entangled CNTs were measured to have an average diameter of 28 nm at 550 °C and one atmospheric (760 Torr) pressure, whereas it was observed to be 78 nm at a temperature of 650 °C and pressure of 0.01 Torr. The field emission response, i.e., the turn-on field (2.5 V/μm) and the maximum emission current density (2.17 mA/cm2) of the CNTs synthesized at the temperature of 550 °C and pressure of 1 atm (760 Torr) was found to be excellent.","PeriodicalId":17652,"journal":{"name":"Journal of Vacuum Science & Technology. B. Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phenomena","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88284815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Development of microfabricated planar slow-wave structures on dielectric substrates for miniaturized millimeter-band traveling-wave tubes 微型化毫米波段行波管介质基板微加工平面慢波结构的研究

Journal of Vacuum Science & Technology. B. Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phenomena Pub Date : 2021-01-22 DOI: 10.1116/6.0000716

N. Ryskin, Roman A. Torgashov, A. Starodubov, A. Rozhnev, A. Serdobintsev, A. Pavlov, V. Galushka, D. Bessonov, G. Ulisse, V. Krozer

{"title":"Development of microfabricated planar slow-wave structures on dielectric substrates for miniaturized millimeter-band traveling-wave tubes","authors":"N. Ryskin, Roman A. Torgashov, A. Starodubov, A. Rozhnev, A. Serdobintsev, A. Pavlov, V. Galushka, D. Bessonov, G. Ulisse, V. Krozer","doi":"10.1116/6.0000716","DOIUrl":"https://doi.org/10.1116/6.0000716","url":null,"abstract":"We report the results of the design, simulation, fabrication, and cold-test measurements of millimeter-band 2D planar microstrip slow-wave structures (SWSs) on dielectric substrates. Such structures have a high slow-wave factor, which allows for low-voltage operation and reduction in the size and weight of the device. A low-cost and flexible fabrication technology based on magnetron sputtering and subsequent laser ablation has been developed and is reported in the paper. Microstrip meander-line SWS circuits at V-, W-, and D-bands have been fabricated and characterized. The fabrication of ring-bar planar SWSs by the photolithographic method is also discussed. Experimental measurement of S-parameters of the fabricated structures reveals good transmission properties. Return loss (S11) does not exceed −10 dB and attenuation is about 2 dB/cm in the V-band, 10 dB/cm in the W-band, and 8.5 dB/cm in the D-band.","PeriodicalId":17652,"journal":{"name":"Journal of Vacuum Science & Technology. B. Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phenomena","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85793769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 13

High signal-to-noise ratio differential conductance spectroscopy 高信噪比差分电导光谱

Journal of Vacuum Science & Technology. B. Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phenomena Pub Date : 2021-01-22 DOI: 10.1116/6.0000823

Hamed Alemansour, S. Moheimani, J. Owen, J. Randall, E. Fuchs

引用次数: 1