10 research outputs found
Effect of wet chemical substrate smoothing on passivation of ultrathin SiO2 n Si 111 interfaces prepared with atomic oxygen at thermal impact energies
No full textUltrathin SiO2 layers for potential applications in nano scale electronic and photovoltaic de vises were prepared by exposure to thermalized atomic oxygen under UHV conditions. Wet chemical substrate pre treatment, layer deposition and annealing processes were applied to improve the electronic Si SiO2 interface properties. This favourable effect of optimized wet chemical pre treatment can be preserved during the subsequent oxidation. The corresponding atomic scale analysis of the electronic interface states after substrate pre treatment and the subsequent silicon oxide layer formation is performed by field modulated surface photovolt age SPV , atomic force microscopy AFM and spectroscopic ellipsometry in the ultra violet and visible region UV VIS S
Development of ultra-thin tunneling oxides and Si/SiO<sub>2</sub> nanostructures for the application in silicon solar cells
No full textМодернизация российской экономики: что в повестке дня
No full textA year ago, at the first international conference of the HSE, the author and his colleagues presented a report reflecting their view of Russia 's economic strategy. Since then, the development of the Gref program has been completed, and a government program for 1.5 years has been adopted. Then, on behalf of the state Council, V. Ishaev 's program was developed. Long-term and medium-term programs are being developed. Comparison of these and other similar documents shows the similarity of their ideas, proposals, and alternatives. At present, it is interesting to consider what ideas and how they are being implemented, in what direction the Russian economy is turning, and what new (or previously missed), threats and opportunities are emerging. This is what this report is about.Год назад, на I Международной конференции ГУ-ВШЭ автор и его коллеги представили доклад, отражающий их взгляд на экономическую стратегию России. С тех пор была завершена разработка программы Г. Грефа, принята правительственная программа на 1,5 года. Затем по поручению Госсовета разработана программа В. Ишаева. Находятся в разработке долгосрочная и среднесрочная программы. Сравнение этих и других подобных документов показывает схожесть их идей, предложений, альтернатив. В настоящее время интересно рассмотреть, какие идеи и как реализуются, в каком направлении поворачивается российская экономика, какие новые (или упущенные ранее) угрозы и возможности возникают. Этому и посвящен настоящий доклад
Grain boundary light beam induced current A characterization of bonded silicon wafers and polycrystalline silicon thin films for diffusion length extraction
No full textThe charge carrier lifetime and accordingly the diffusion length in polycrystalline semiconductor materials is known to be detrimentally influenced by disordered interfaces like grain boundaries GBs . The GB light beam induced current GB LBIC technique is suitable for the extraction of the minority charge carrier diffusion length in unprocessed polycrystalline materials. This measurement method is based on the GB itself acting as a charge collector. A spatially resolved light beam induced current can thus be measured even without a collecting p n junction or Schottky contact, and without biasing the sample. In this contribution we present a simulation based analysis of measured GB LBIC line scans on bonded silicon wafers and polycrystalline silicon thin films with different laser wavelengths and intensitie
Fabbisogni energetici per edifici caratterizzanti il terziario in Italia: aspetti termici ed illuminotecnici
No full textIl presente lavoro verte sull'individuazione di benchmark di fabbisogno energetico per edifici di riferimento con destinazione d'uso non-residenziale. In particolare, si intende fornire profili tipo di domanda energetica per l'illuminazione artificiale, al fine di valutarne l'effetto sui profili di fabbisogno di energia per la climatizzazione estiva ed invernale, nonché di individuare le variabili che maggiormente incidono sulla loro determinazione. Per giungere a questi risultati, ci si avvale dell'uso di programmi informatici di simulazione dinamica riconosciuti ed impiegati a livello scientifico, in ambito europeo ed extraeuropeo (Energy Plus). La ricerca viene condotta sotto vari aspetti: architettonico, energetico e ambientale. Il primo obiettivo, partendo dalle indicazioni bibliografiche, legislative e normative, è quello di caratterizzare in modo univoco gli edifici di riferimento per le varie destinazioni d'uso oggetto di analisi: edifici per l'istruzione, ed edifici terziari. Gli edifici di riferimento intendono costituire archetipi rappresentativi del patrimonio edilizio italiano. Il secondo obiettivo è di tipo energetico: si intende definire profili tipo di domanda energetica per l'illuminazione artificiale degli ambienti. Si intendono inoltre valutare contestualmente i fabbisogni energetici netti per il riscaldamento e il raffrescamento degli ambienti. L'obiettivo finale è riuscire a determinare le migliori soluzioni progettuali per la minimizzazione del fabbisogno di energia connesso all'illuminazione, in relazione alle destinazioni d'uso dei differenti edifici, nonché le variabili che più incidono per indirizzare al meglio le attenzioni progettuali in caso di nuova realizzazione. Il presente lavoro, dopo un primo inquadramento generale in cui si delinea quello che è lo stato dell'arte della valutazione dei fabbisogni energetici e della ricerca scientifica in materia di illuminazione artificiale di ambienti non residenziali, passa poi ad indagare il significato di archetipo e a definire degli archetipi edilizi per il patrimonio immobiliare costruito a destinazione d'uso scolastica e terziaria. Successivamente vengono descritti i modelli di calcolo impiegati e sono dettagliati i dati di input impiegati per la loro definizione. Sono infine esplicati i risultati ottenuti, con individuazione dei valori di benchmark energetico per gli archetipi edilizi scolastici e terziari, e con l'analisi di quelle che sono le grandezze maggiormente influenti sul fabbisogno energetico per illuminazion
Comparison of growth methods for Si SiO2 nanostructures as nanodot hetero emitters for photovoltaic applications
No full textTwo different growth mechanisms are compared for the fabrication of Si SiO2 nanostructures on crystalline silicon c Si to be used as hetero emitter in high efficiency solar cells 1 The decomposition of substoichiometric amorphous SiOx a SiOx films with 0bxb1.3 and 2 the dewetting of thin amorphous silicon a Si layers. The grown layers are investigated with regard to their structural properties, their passivation quality for c Si wafer substrates and their electrical properties in order to evaluate their suitability as a nanodot heteroemitter. While by layer decomposition, no passivating nanodots could be formed, the dewetting process allows fabricating nanodot passivation layers at temperatures as low as 600 C. The series resistance through Ag [Si nanodots in SiO2] c Si Al structures for dewetting is similar to nanostructured silicon rich SiOx films. Still, a nanodot hetero emitter which exhibits both a satisfying passivation of the substrate and induces a high band bending by doping at the same time could not be fabricated ye
Photoconductivity and optical properties of silicon coated by thin TiO2 film in situ doped by Au nanoparticles
No full textLight trapping enhancement by plasmonic active metal nanoparticles NPs is believed to be a promising approach to increase silicon based solar cell efficiency. Therefore, we investigated TiO2 films in situ doped by Au NPs TiO2 AuNPs deposited by spin coating on a silicon substrate. Photoconductivity and optical properties of the TiO2 AuNPs Si structures were studied in comparison with those of TiO2 Si reference samples. We found that an introduction of the 4050nm diameter AuNPs into the antireflective TiO2 layer deteriorates the antireflection properties and decreases the external yield of photogeneration of charge carriers. This is due to an increase of the layer reflection in the red IR part of the spectrum, and due to the parasitic absorption of light by AuNPs in the blue green part. Charge carrier recombination effect at the TiO2 AuNPs Si interface is also found to decrease the external yield. We conclude that the TiO2 AuNPs layers could potentially be applied on the rear but not on the front side of Si solar cell
Controlling the thermal impact of ns laser pulses for the preparation of the P2 interconnect by local phase transformation in CIGSe
No full textThe Strong Man Vladimir Putin and the Struggle for Russia (Book Review)
No full textThe former BBC Moscow correspondent Angus Roxburgh who became a Kremlin media consultant wrote this book when he was a chief consultant for a four-part BBC television documentary titled ‘Putin, Russia & the West’. His top-level interviews in Russia, the US, Britain, France, Germany, Ukraine and Georgia are also used to fill out the details of the events covered in his book. The author has used his personal experiences as an advisor for three years to President Putin’s press secretary, Dmitry Peskov. Roxburgh presents Russia’s struggle for their future under Putin after the collapse of communism, her isolation for decades from the Western world, the failure of the West to understand her fears and aspirations during this new transformation with respect and her ambitions as a country that wants to be part of the world. The book is comprised of an introduction and sixteen chapters. Chapter one starts with the announcement of Yeltsin’s resignation and his designation of Putin as his successor, and Putin’ s inheritance from Yeltsin of a Russia that was economically and militarily weak, run by thugs, and patronized by the West. The author gives us very clear picture of a country dealing with mafia-style gangs, killings, and soaring inflation. He describes how impoverished Russians were selling their belongings on the pavements; Moscow had become a huge flea-market, railway stations were filled with beggars and homeless people, industries had collapse, and enterprises conducted business with each other by barter etc. The abrupt transition from communism and the loss of their own country shocked the Russians: the Soviet Union, a land of 250 million people in 15 national republics, had fallen apart. Twenty-five million Russians suddenly found themselves foreigners in their countries. The author states that the Kremlin’s Western advisors did not know how to handle this dislocated society; and Western countries did not notice the chaos since they were obsessed with the idea of building capitalism, regardless of its immediate impact. The West assumed that Russians would simply know how to use their liberty; transformation would be quick and chaos was something totally natural in a transitional period that would soon be replaced by normal life. In Chapter two, the author talks about Putin’s conciliatory gestures to the West, his approval of the closure of two Soviet-era military facilities abroad – a naval base at Cam Ranh Bay in Vietnam and a listening post at Lourdes in Cuba; his cooperation with America in dealing with the Taliban issue etc. Chapter three is about his battle for economic reform. The author states that although Yeltsin carried out major projects such as mass privatization and the liberalization of prices that transformed the economy, the country did not have sustainable economic growth, inflation was high and the new private sector worked inefficiently. He emphasizes that Putin impressed the West with his economic reforms that stimulated the economy, and established the free market with the help of a new team of Western-oriented reformers to draw up a program. The author provides detailed information on briefings and sessions, projects and plans. He states that the Gref plan that was approved in 2000 during Putin’s first term introduced tax and progressive pension reforms, adopted a new land code that made it possible to buy and sell commercial and residential land, eliminated barriers to opening and running a business, introduced civil service reforms, reduced personal income tax, and sped up negotiations on Russia’s joining the WTO. This led to a sharp acceleration of economic growth, an influx of foreign investment and the strengthening of the ruble. In Chapter four, Roxburgh talks about the crackdown on the free media. He states that Western traditions of balance and independence had not taken root under Putin, and one of Putin’s earliest decisions was to start creating what he called the ‘vertical of power’, the gathering-in of all political power to the center, and effectively into his own hands. In Chapter five, the author talks about Putin’s concerns on whether Russia would be excluded from the top table, his belief that Russia was not being treated as a superpower any more, his craving for respect from the West and his Western-style approach to alliances by creating a new NATO–Russia Council to include the Russians in the Western alliance. This chapter also provides information on tensions over the Iraq issue and the growing confrontation with America on the cancellation of America’s missile defense plans etc. Chapter six concerns the start of what became known as the Rose Revolution that ousted Eduard Shevardnadze, ended the Soviet era of leadership in the country (which Putin saw it as a threat to Russia itself), brought Mikheil Saakashvili to power, democracy to countries on Russia’s borders, and orientated Georgia towards the West. Chapter seven, gives information on the Orange Revolution, a series of protests and political events that took place in Ukraine (seen by Putin as the most important for Russia of all the former Soviet republics since it was the last buffer between Russia and the ever-expanding NATO) in November 2004, his efforts to sort things out, how Ukraine became a battleground for influence, with the United States, Russia’s open support for both opposing candidates, and Putin’s reactions and his sanctions (the gas wars). In Chapter eight, the author talks about the aftermath of the Orange Revolution in 2005, and how the West became powerless when Putin began to curtail democracy, create Nashi (Youth Democratic Anti-Fascist Movement), crack down on Non-Governmental Organizations and turn off gas supplies to Ukraine, murder of the dissident journalist Anna Politkovskaya, URPO’s violence (Division of Operations against Criminal Organizations) within the Federal Security Service, growing tension between Russia and America over recent event in Georgia, America’s threat to step in in case Russia does anything in Georgia. Chapter nine is based on Roxburgh’s own experiences as the chief Russia consultant and working for three years as an adviser to President Putin’s press secretary, Dmitry Peskov. It talks about Putin’s negative image created by his increasing authoritarianism, his stifling the opposition and increasing control over NGOs, and the murders of Politkovskaya and other journalists that resulted in calls from conservative quarters of the G8 to expel Russia from the organization. The main task of Russia’s leadership was to burnish that image with the help of a Western public-relations company, so an American PR organization Ketchum and its Brussels-based partner, GPlus were employed by the Kremlin as a propaganda tool. The author mentions his work experience with Ketchum and Gplus, the state-controlled Russia Today (RT) and the Kremlin. He also discusses the invasion of Georgia and how it destroyed the positive efforts made by Putin. In Chapter ten, the author talks about why Putin opposed the recognition of Kosovo’s independence, which he believed would encourage a separatist movement in the Caucasus, and would send a message to the Chechens, the Abkhazians and South Ossetians that their demand to secede would not be ignored. He also discusses the Russo-Georgian war, the approach of the West to it, and its consequences. Chapter eleven is about the backlash to the Caucasian war, the gas conflict with Ukraine, Russia’s relationship with the new US president Obama, Medvedev’s changing the agenda at home, and his foreign policy objectives to reconcile with the West over Iran. Chapter twelve examines the global crisis and its effects on Putin’s Russia in 2008 that exposed the weakness of semi-reformed economy, the government’s effort to prevent the collapse of the banking system, and corruption which was the biggest obstacle to foreign investment, as well as the destroyer of the economy and a politically explosive issue. In Chapter thirteen, the author discusses the question of whether there are signs of a division in the ruling tandem of Prime Minister Vladimir Putin and President Dmitry Medvedev and examines the similarities and differences between the two leaders. Chapter fourteen begins with Putin’s dramatic announcement of the scenario that had been created by the two leader to alternate between the positions of the presidency and prime minister. It talks about the 2012 election, the treatment of the opposition, and the dictatorship of the law by Putin and legal nihilism by Medvedev that became a tool of political repression. The chapter also stresses the contradictory attitudes of Russia towards the West: the West is viewed by Putin Mark III as prosperous and successful but at the same time evil because of their double standards and their support and financing of the opposition. For him ‘Russia’s democracy means the power of the Russian people with their own traditions of self-rule and not the fulfilment of standards imposed on them from the outside’. Chapter fifteen provides information on a confident Putin ready to offer Russian values as an alternative to Western liberal democracy, and Russia itself as a bastion of conservative, traditional values that occupies a superior place with its own sphere of influence and legitimate security interests. The chapter also examines the Putin’s Crimean adventure which put enormous strain on Russia’s budget, his strict control over the media and internet, the GRU (military intelligence agency)’s involvement in illegal activities, and Russia’s war in Syria. In Chapter sixteen, the author talks about Putin’s fear that he was not allowed to run again in 2024, and his genuine worry that the oligarchy he has created is becoming autonomous. He states that their growing concerns and distrust drive them to consider scenarios for Russia’s future under Putin and after he is gone. According to Roxburgh, Putin’s control over the oligarchs and cronies is complicated; his system is “corrupt, larcenous and incestuous and stable only so long as the lynchpin at its center remained in place”. The book is written by Roxburgh, an eyewitness to Russia’s transition from communism to today’s Russia, and it is valuable as a first-hand source for information about the people and events of the Putin era. It is an excellent supplement to use in conjunction with other, more official sources
«Цифра» и «цифровое общество» как симулякры XXI века (о терминологической строгости при описании процессов коммуникации)
No full textIn this article the author traces the history of the term «digit» and its derivatives («digital») from the original to the modern meaning and the process of changing its content. He comes to the conclusion that currently «digital technologies» refers to information technology, as well as industrial technology controlled by computer systems operating on the basis of the binary number system. The author makes a brief excursion into the history of positional number systems and emphasizes that the binary system was not the most popular in the past, but it was known, and a number of major thinkers foresaw its relevance in the future. The author states that digital devices are resistant to interference, and their advantages are in signal processing. At the same time, the meaning (content) has always belonged of the actors of communication. The author notes that, as is often the case, the term «digit»(«digital») has undergone metonymic transformation: being a representative of the class (science-intensive technologies), it started to mean the whole class. In addition, it began to denote qualitative novelty – not only technical, but also social. But in contrast to the «classical» metonymy, in which the rhetorical character and figurative meaning are perceived, in most «digital» cases there is no reflection. As a result, largely for career and/or opportunistic reasons, the term begins to denote something that actually cannot denote, for the technical characteristics of the economy and production do not make them qualitatively different. Thus, we obviously have a typical case: a signifier without a significate, that is, the simulacrum.В статье автор прослеживает историю возникновения термина «цифра» и его производных («цифровой», «цифровая») – от исходного до современного значения – и процесс изменения его содержания. Он приходит к выводу о том, что в настоящее время под «цифровыми технологиями» понимаются информационные технологии, а также промышленные технологии, управляемые системами компьютеров, работающих на основе двоичной системы счисления. Автор делает краткий экскурс в историю позиционных систем счисления и подчеркивает, что двоичная система была не самой популярной в прежние времена, однако она была известна, и ряд крупных мыслителей предвидел ее востребованность в будущем. Автор констатирует, что цифровые устройства отличает устойчивость к помехам, и их преимущества заключаются в обработке сигнала. В то же время смысл (содержание) был и остается принадлежностью субъектов коммуникации. Автор замечает, что, как это часто бывает, с термином «цифра» («цифровой») произошла метонимическая трансформация: он как представитель класса (наукоемкие технологии) стал означать весь класс. Плюс к этому он стал обозначать качественную новизну – не только техническую, но и социальную. Но в отличие от «классической» метонимии, в которой риторичный характер и переносный смысл осознается, здесь рефлексия в большинстве случаев отсутствует. В результате – в значительной мере из соображений карьерного и/или конъюнктурного характера – термин начинает обозначать то, чего на самом деле обозначать не может, так как техническая характеристика экономики и производства не делает их качественно иными. Таким образом, налицо типичный случай обозначающего без обозначаемого, т. е. симулякра
