Application of the SEM to the measurement of solar cell parameters

Techniques are described which make use of the SEM to measure the minority carrier diffusion length and the metallurgical junction depth in silicon solar cells. The former technique permits the measurement of the true bulk diffusion length through the application of highly doped field layers to the back surfaces of the cells being investigated. It is shown that the secondary emission contrast observed in the SEM on a reverse-biased diode can depict the location of the metallurgical junction if the diode has been prepared with the proper beveled geometry. The SEM provides the required contrast and the option of high magnification, permitting the measurement of extremely shallow junction depths

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

Spin-Orbit induced phase-shift in Bi2_{2}Se3_{3} Josephson junctions

The transmission of Cooper pairs between two weakly coupled superconductors produces a superfluid current and a phase difference; the celebrated Josephson effect. Because of time-reversal and parity symmetries, there is no Josephson current without a phase difference between two superconductors. Reciprocally, when those two symmetries are broken, an anomalous supercurrent can exist in the absence of phase bias or, equivalently, an anomalous phase shift $\varphi_0$ can exist in the absence of a superfluid current. We report on the observation of an anomalous phase shift $\varphi_0$ in hybrid Josephson junctions fabricated with the topological insulator Bi$_2$Se$_3$ submitted to an in-plane magnetic field. This anomalous phase shift $\varphi_0$ is observed directly through measurements of the current-phase relationship in a Josephson interferometer. This result provides a direct measurement of the spin-orbit coupling strength and open new possibilities for phase-controlled Josephson devices made from materials with strong spin-orbit coupling

Fabrication and analogue applications of nanoSQUIDs using Dayem bridge junctions

We report here recent work at the U.K. National Physical Laboratory on developing nanoscale SQUIDs using Dayem bridge Josephson junctions. The advantages are simplicity of fabrication, exceptional low-noise performance, toward the quantum limit, and a range of novel applications. Focused ion beam patterned Nb SQUID, possessing exceptionally low noise (∼200 nΦ0/Hz1/2 above 1 kHz), and operating above 4.2 K can be applied to measurement of nanoscale magnetic objects or coupled to nanoelectromechanical resonators, as well as single particle detection of photons, protons, and ions. The limited operating temperature range may be extended by exposing the Dayem bridges to carefully controlled ion beam implantation, leading to nonreversible changes in junction transition temperature.The work reported here was supported in part by the EMRP projects ‘MetNEMS’ NEW-08 and ‘BioQUART’SIB-06. The EMRP is jointly funded by the EMRP participating countries within EURAMET and the European Union

Proximity induced superconductivity by Bi in topological Bi2Te2SeBi_2Te_2Se and Bi2Se3Bi_2Se_3 films: Evidence for a robust zero energy bound state possibly due to Majorana Fermions

Point contact conductance measurements on topological $Bi_2Te_2Se$ and $Bi_2Se_3$ films reveal a signature of superconductivity below 2-3 K. In particular, critical current dips and a robust zero bias conductance peak are observed. The latter suggests the presence of zero energy bound states which could be assigned to Majorana Fermions in an unconventional topological superconductor. We attribute these novel observations to proximity induced local superconductivity in the films by small amounts of superconducting Bi inclusions or segregation to the surface, and provide supportive evidence for these effects.Comment: Accepted for publication in Physical Review B (Dec. 20, 2011), 15 figures. Version V1: arXiv:1111.3445v1 [cond-mat.supr-con] 15 Nov 201

Josephson supercurrent in a topological insulator without a bulk shunt

A Josephson supercurrent has been induced into the three-dimensional topological insulator Bi1.5Sb0.5Te1.7Se1.3. We show that the transport in Bi1.5Sb0.5Te1.7Se1.3 exfoliated flakes is dominated by surface states and that the bulk conductivity can be neglected at the temperatures where we study the proximity induced superconductivity. We prepared Josephson junctions with widths in the order of 40 nm and lengths in the order of 50 to 80 nm on several Bi1.5Sb0.5Te1.7Se1.3 flakes and measured down to 30 mK. The Fraunhofer patterns unequivocally reveal that the supercurrent is a Josephson supercurrent. The measured critical currents are reproducibly observed on different devices and upon multiple cooldowns, and the critical current dependence on temperature as well as magnetic field can be well explained by diffusive transport models and geometric effects

Reversible writing of high-mobility and high-carrier-density doping patterns in two-dimensional van der Waals heterostructures

A key feature of two-dimensional materials is that the sign and concentration of their carriers can be externally controlled with techniques such as electrostatic gating. However, conventional electrostatic gating has limitations, including a maximum carrier density set by the dielectric breakdown, and ionic liquid gating and direct chemical doping also suffer from drawbacks. Here, we show that an electron-beam-induced doping technique can be used to reversibly write high-resolution doping patterns in hexagonal boron nitride-encapsulated graphene and molybdenum disulfide (MoS2) van der Waals heterostructures. The doped MoS2 device exhibits an order of magnitude decrease of subthreshold swing compared with the device before doping, whereas the doped graphene devices demonstrate a previously inaccessible regime of high carrier concentration and high mobility, even at room temperature. We also show that the approach can be used to write high-quality p–n junctions and nanoscale doping patterns, illustrating that the technique can create nanoscale circuitry in van der Waals heterostructures

Investigating the intrinsic noise limit of Dayem bridge NanoSQUIDs

NanoSQUIDs made from Nb thin films have been produced with nanometre loop sizes down to 200 nm, using weak-link junctions with dimensions less than 60 nm. These composite (W/Nb) single layer thin film devices, patterned by FIB milling, show extremely good low-noise performance ∼170 nΦ0 at temperatures between 5 and 8.5 K and can operate in rather high magnetic fields (at least up to 1 T). The devices produced so far have a limited operating temperature range, typically only 1–2 K. We have the goal of achieving operation at 4.2 K, to be compatible with the best SQUID series array (SSA) preamplifier available. Using the SSA to readout the nanoSQUIDs provides us with a means of investigating the intrinsic noise of the former. In this paper we report improved white noise levels of these nanoSQUIDs, enabling potential detection of a single electronic spin flip in a 1-Hz bandwidth. At low frequencies the noise performance is already limited by SSA preamplifier noise