A Model of High-Frequency Self-Mixing in Double-Barrier Rectifier

In this paper, a new model of the frequency dependence of the double-barrier THz rectifier is presented. The new structure is of interest because it can be realized by CMOS image sensor technology. Its application in a complex field such as that of THz receivers requires the availability of an analytical model, which is reliable and able to highlight the dependence on the parameters of the physical structure. The model is based on the hydrodynamic semiconductor equations, solved in the small signal approximation. The model depicts the mechanisms of the THz modulation of the charge in the depleted regions of the double-barrier device and explains the self-mixing process, the frequency dependence, and the detection capability of the structure. The model thus substantially improves the analytical models of the THz rectification available in literature, mainly based on lamped equivalent circuits

New insight on terahertz rectification in a metal–oxide–semiconductor field-effect transistor structure

The use of a metal–oxide–semiconductor field-effect transistor (MOS-FET) permits the rectification of electromagnetic radiation by employing integrated circuit technology. However, obtaining a high-efficiency rectification device requires the assessment of a physical model capable of providing a qualitative and quantitative explanation of the processes involved. For a long time, high-frequency detection based on MOS technology was explained using plasma wave detection theory. In this paper, we review the rectification mechanism in light of high-frequency numerical simulations, showing features never examined until now. The results achieved substantially change our understanding of terahertz (THz) rectification in semiconductors, and can be interpreted by the model based on the self-mixing process in the device substrate, providing a new and essential tool for designing this type of detector

On a flexible construction of a negative binomial model

This work presents a construction of stationary Markov models with negative-binomial marginal distributions. A simple closed form expression for the corresponding transition probabilities is given, linking the proposal to well-known classes of birth and death processes and thus revealing interesting characterizations. The advantage of having such closed form expressions is tested on simulated and real data.Comment: Forthcoming in "Statistics & Probability Letters

CMOS-Compatible Room-Temperature Rectifier Toward Terahertz Radiation Detection

In this paper, we present a new rectifying device, compatible with the technology of CMOS image sensors, suitable for implementing a direct-conversion detector operating at room temperature for operation at up to terahertz frequencies. The rectifying device can be obtained by introducing some simple modifications of the charge-storage well in conventional CMOS integrated circuits, making the proposed solution easy to integrate with the existing imaging systems. The rectifying device is combined with the different elements of the detector, composed of a 3D high-performance antenna and a charge-storage well. In particular, its position just below the edge of the 3D antenna takes maximum advantage of the high electric field concentrated by the antenna itself. In addition, the proposed structure ensures the integrity of the charge-storage well of the detector. In the structure, it is not necessary to use very scaled and costly technological nodes, since the CMOS transistor only provides the necessary integrated readout electronics. On-wafer measurements of RF characteristics of the designed junction are reported and discussed. The overall performances of the entire detector in terms of noise equivalent power (NEP) are evaluated by combining low-frequency measurements of the rectifier with numerical simulations of the 3D antenna and the semiconductor structure at 1 THz, allowing prediction of the achievable NEP

Terahertz rectifyier for integrated image detector

We present a new CMOS compatible direct conversion terahertz detector operating at room temperature. The rectenna consists in a truncated conical helix extruded from a planar spiral and connected to a nanometric metallic whisker at one of its edges. The whisker reaches the semiconductor substrate that constitutes the antenna ground plane. The rectifying device can be obtained introducing some simple modifications of the charge storage well in conventional CMOS APS devices, making the proposed solution easy to integrate with existing imaging systems. No need of scaling toward very scaled and costly technological node is required, since the CMOS only provides the necessary integrated readout electronics. On-wafer measurements of RF characteristics of the designed rectifying junction are reported and discussed

Porous silicon solar cells

We developed a new process for the fabrication of crystalline solar cell, based on an ultrathin silicon membrane, taking advantage of porous silicon technology. The suggested architecture allows the costs reduction of silicon based solar cell reusing the same wafer to produce a great number of membranes. The architectures combines the efficiency of crystalline silicon solar cell, with the great absorption of porous silicon, and with a more efficient way to use the material. The new process faces the main challenge to achieve an effective and not expensive passivation of the porous silicon surface, in order to achieve an efficient photovoltaic device. At the same time the process suggests a smart way to selective doping of the macroporous silicon layers despite the through-going pores. © 2015 IEEE. SciVal Topic Prominence  Topic: Porous silicon | Silicon | macroporous silicon Prominence percentile: 66.984  Author keywords nanofabricationporous siliconsilicon nanoelectronicssolar cells Indexed keywords Engineering controlled terms: Crystalline materialsNanoelectronicsNanostructured materialsNanotechnologyPorous siliconSiliconSilicon wafersSolar cells Engineering uncontrolled terms Crystalline silicon solar cellsCrystalline solar cellsMacro porous siliconPhotovoltaic devicesPorous silicon surfacesPorous silicon technologySilicon nanoelectronicsUltrathin silicon membrane Engineering main heading: Silicon solar cells ISBN: 978-146738155-0 Source Type: Conference Proceeding Original language: English DOI: 10.1109/NANO.2015.7388710 Document Type: Conference Paper Sponsors: Nanotechnology Council Publisher: Institute of Electrical and Electronics Engineers Inc. References (9) View in search results format ▻ All Export  Print  E-mail Save to PDF Create bibliography 1 (2012) International Technology Roadmap for Photovoltaics Results 2012. Cited 24 times. ITRPV, Third Edition, Berlin 2012 www.ITRPV.net 2 Lehmann, V., Honlein, W., Stengl, R., Willer, J., Wendt, H. (1992) Verfahren Zur Herstellung Einer Solarzelle Aus Einer Substratscheibe. Cited 6 times. German patent DE4204455C1; Filing date: 29. 01. 3 Brendel, R., Ernst, M. Macroporous Si as an absorber for thin-film solar cells (2010) Physica Status Solidi - Rapid Research Letters, 4 (1-2), pp. 40-42. Cited 22 times. http://www3.interscience.wiley.com/cgi-bin/fulltext/123215552/PDFSTART doi: 10.1002/pssr.200903372 Locate full-text(opens in a new window) View at Publisher 4 Ernst, M., Brendel, R., Ferré, R., Harder, N.-P. Thin macroporous silicon heterojunction solar cells (2012) Physica Status Solidi - Rapid Research Letters, 6 (5), pp. 187-189. Cited 16 times. doi: 10.1002/pssr.201206113 Locate full-text(opens in a new window) View at Publisher 5 Ernst, M., Brendel, R. Macroporous silicon solar cells with an epitaxial emitter (2013) IEEE Journal of Photovoltaics, 3 (2), art. no. 6472253, pp. 723-729. Cited 7 times. doi: 10.1109/JPHOTOV.2013.2247094 Locate full-text(opens in a new window) View at Publisher 6 Ernst, M., Schulte-Huxel, H., Niepelt, R., Kajari-Schröder, S., Brendel, R. Thin crystalline macroporous silicon solar cells with ion implanted emitter (Open Access) (2013) Energy Procedia, 38, pp. 910-918. Cited 2 times. http://www.sciencedirect.com/science/journal/18766102 doi: 10.1016/j.egypro.2013.07.364 Locate full-text(opens in a new window) View at Publisher 7 Nenzi, P., Kholostov, K., Crescenzi, R., Bondarenka, H., Bondarenko, V., Balucani, M. Electrochemically etched TSV for porous silicon interposer technologies (2013) Proceedings - Electronic Components and Technology Conference, art. no. 6575887, pp. 2201-2207. Cited 2 times. ISBN: 978-147990233-0 doi: 10.1109/ECTC.2013.6575887 Locate full-text(opens in a new window) View at Publisher 8 Perticaroli, S., Varlamava, V., Palma, F. Microwave sensing of nanostructured semiconductor surfaces (2014) Applied Physics Letters, 104 (1), art. no. 013110. Cited 3 times. doi: 10.1063/1.4861424 Locate full-text(opens in a new window) View at Publisher 9 De Cesare, G., Caputo, D., Tucci, M. Electrical properties of ITO/crystalline-silicon contact at different deposition temperatures (2012) IEEE Electron Device Letters, 33 (3), art. no. 6142006, pp. 327-329. Cited 28 times. doi: 10.1109/LED.2011.2180356 Locate full-text(opens in a new window) View at Publisher © Copyright 2017 Elsevier B.V., All rights reserved. ◅ Back to results ◅ Previous 3of10 Next ▻  Top of page Metrics Learn more about article metrics in Scopus (opens in a new window)  0 Citations in Scopus 0 Learn more about Field-Weighted Citation Impact Field-Weighted Citation Impact PlumX Metrics Usage, Captures, Mentions, Social Media and Citations beyond Scopus.  Cited by 0 documents Inform me when this document is cited in Scopus: Set citation alert ▻ Set citation feed ▻ Related documents Thin crystalline macroporous silicon solar cells with ion implanted emitter Ernst, M. , Schulte-Huxel, H. , Niepelt, R. (2013) Energy Procedia Multilayer etching for kerf-free solar cells from macroporous silicon Schäfer, S. , Ernst, M. , Kajari-Schröder, S. (2013) Energy Procedia Macroporous silicon solar cells with an epitaxial emitter Ernst, M. , Brendel, R. (2013) IEEE Journal of Photovoltaics View all related documents based on references Find more related documents in Scopus based on: Authors ▻ Keywords ▻ About Scopus What is Scopus Content coverage Scopus blog Scopus API Privacy matters Language 日本語に切り替える 切换到简体中文 切換到繁體中文 Русский язык Customer Service Help Contact us Elsevier Terms and conditions ↗ Privacy policy ↗ Copyright © 2018 Elsevier B.V ↗. All rights reserved. Scopus® is a registered trademark of Elsevier B.V. We use cookies to help provide and enhance our service and tailor content. By continuing, you agree to the use of cookies. RELX Group We developed a new process for the fabrication of crystalline solar cell, based on an ultrathin silicon membrane, taking advantage of porous silicon technology. The suggested architecture allows the costs reduction of silicon based solar cell reusing the same wafer to produce a great number of membranes. The architectures combines the efficiency of crystalline silicon solar cell, with the great absorption of porous silicon, and with a more efficient way to use the material. The new process faces the main challenge to achieve an effective and not expensive passivation of the porous silicon surface, in order to achieve an efficient photovoltaic device. At the same time the process suggests a smart way to selective doping of the macroporous silicon layers despite the through-going pores

The Italian experience of the national registry of renal biopsies

The Italian experience of the national registry of renal biopsies.BackgroundAlthough several registries collecting data of patients with kidney diseases exist, there are only a few registries which specifically collect data relating to renal biopsy; one such registry is the Italian Registry of Renal Biopsies (IRRB). The aim of this study was to report on the relative frequency of nephropathies according to gender, age at time of biopsy, clinical presentation and renal function, based on the histologic diagnosis during the years 1996 to 2000.MethodsWe evaluated data relating to 14607 renal biopsies, provided by 128 renal units in Italy. Data entry was performed by using the Internet-based database directly (URL http://www.irrb.net). Clinical presentation was defined as urinary abnormalities (UA), nephrotic syndrome (NS), acute nephritic syndrome (ANS). Renal diseases were divided in four major categories: (1) primary glomerulonephritides (GN); (2) secondary GN; (3) tubulointerstitial nephropathies (TIN); and (4) vascular nephropathies (VN).ResultsPrimary GN, TIN, and VN were more frequent in males compared to females while secondary GN was more frequent in females. Diseases whose frequency was higher in males were IgA nephropathy (IgAN), benign nephroangiosclerosis (BNA), and acute tubular necrosis (ATN). A significantly higher frequency of immune-mediated secondary GN, as well as primary GN, including minimal change disease (MCD), focal segmental glomerulosclerosis (FSGS), and mesangiocapillary GN (MCGN), was shown in females. Primary and secondary GN, TIN, and VN were more frequent in the range 15 to 65 years of age. At the time of biopsy 77% of primary GN and 61% of secondary GN presented with normal renal function. Acute renal failure (ACR) was more present in TIN (52%), while chronic renal failure (CRF) was more frequent in VN (47%).ConclusionWe believe collection of data relating to renal biopsies in a national registry is a useful tool for nephrologists in that it meets one of the current challenges facing the clinical research enterprise. The availability of these data will allow epidemiologic studies in health care to answer the several open questions in both prevention and treatment of renal diseases

Occurrence of arsenic species in algae and freshwater plants of an extreme arid region in northern Chile, the Loa River Basin

This study reports data on arsenic speciation in two green algae species (Cladophora sp. and Chara sp.) and in five aquatic plants (Azolla sp., Myriophyllum aquaticum, Phylloscirpus cf. desserticola, Potamogeton pectinatus, Ruppia filifolia and Zannichellia palustris) from the Loa River Basin in the Atacama Desert (northern Chile). Arsenic content was measured by Mass Spectrometry coupled with Inductively Coupled Plasma (ICP-MS), after acidic digestion. Liquid Chromatography coupled to ICP-MS was used for arsenic speciation, using both anionic and cationic chromatographic exchange systems. Inorganic arsenic compounds were the main arsenic species measured in all samples. The main arsenic species in the extracts of freshwater algae and plants were arsenite and arsenate, whereas glycerol-arsenosugar (gly-sug), dimethylarsinic acid (DMA) and methylarsonic acid (MA) were present only as minor constituents. Of the samples studied, algae species accumulated more arsenic than aquatic plants. Total arsenic content ranged from 182 to 11,100 and from 20 to 248 mg As kg-1 (d.w.) in algae and freshwater plants, respectively. In comparison with As concentration in water samples, there was hyper-accumulation (>0.1% d.w.) in Cladophora sp