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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
221

Country Views

Massie, Rebecca 01 January 2005 (has links)
Over the years I have created many different images and explored a variety of media along my artistic journey. Similar images continue to occur in my work - images from my life as a child and as an adult in rural settings. I lived on a poultry farm and was involved in working with my parents there. When I married, my husband was a cattle farmer so I continued to live on a farm and use rural images in my work. Living in the country makes me constantly aware of the relationship between God, nature and man. I believe that we can find beauty in the most ordinary objects or places. My artwork is intended to help others find this beauty.
222

EXPERIMENTAL PROBING OF CHARGE AND VALLEY COUPLED SPIN DEGREES OF FREEDOM IN TWO-DIMENSIONAL TRANSITION METAL DICHALCOGENIDES

Yi-Tse Hung (7046831) 13 August 2019 (has links)
<div>Charge degree of freedom has been successfully manipulated in the semiconductor industry over the past few decades. The trend of doubling the number of transistors every two years in each chip was observed by Gordon Moore at 1965 and this observation was named after him, Moores law. People have kept up with the prediction fairly well till very recently when the fundamental physics limitations has reached in the conventional Si-based devices. All variety of materials and different degrees of freedom are being explored intensively to make novel device designs to overcome this challenge. In this dissertation, we will focus on two-dimensional transition metal dichalcogenides (TMDs) materials and explore not only charge but also valley and spin degrees of freedom. 2D TMDs have attracted a lot of attention for many reasons and one of them is their superior electrostatic control due to the lowering of dimensionality from 3D to 2D. Such reduction of the dimensionality besides the easiness of doping, on the other hand, makes good metal contact harder to achieve due to its inert surface comparing to the existing Si technology. To evaluate the possibility of being one of the promising candidates of post-CMOS (complementary metal oxide semiconductor) devices, the access to both electrons (conduction band) and holes (valence band) is required in order to make CMOS devices. Fermi-level pinning in these materials, however, severely limits the tunability of the Fermi level alignment between metal and semiconductor by choosing different metal work functions. In Chapter 2, we will discuss our results on making good contact by lowering the Schottky barrier height and having atomically precise doping layer control and its associated doping level where we also achieved the record high hole branch current at the bias volt- age of -1V. Besides the manipulation of charge degree of freedom, we also explored and demonstrated the unique valley degree of freedom that can be electrically generated and detected for the first time in Chapter 3. Many fascinating properties of valley physics can be analogized to spin physics, such as, zero dissipation pure spin/valley current and binary nature (spin +1/2 and -1/2, valley K and K’). Due to the unique lattice structure in TMDs, monolayer particularly, the inversion symmetry is intrinsically broken which lifts the Kramers degeneracy and leads to non-zero Berry curvature. As a result, it possesses valley Hall effect. Even more interestingly, when the transport carriers are in the valence band of monolayer TMDs, spin and valley are locked and it is called spin-locked valley Hall effect. Owing to the nature of being 2D materials, these spins’ polarization is out-of-plane unlike the conventional spin Hall effect materials, such as Pt, Ta, and W, where spins are polarized in the surface plane. This out-of-plane polarization is particularly favorable in the SOT-magnetic random access memory (SOT-MRAM) applications due to the lowering of critical switching current and consequently the reducing of power consumption. We directly observed this spin-locked valley Hall effect for the first time and we will discuss it in Chapter 4.</div>
223

Goya's grotesque : abjection in los Caprichos, Desastres de la Guerra, and los Disparates

Herbst, Michael January 1999 (has links)
Thesis (Ph.D.)--University of the Witwatersrand, Arts Faculty (Fine Arts), 1999 / My basic premise in this study is, if abjection is a psychosocial phenomenon, even a kind of waste category and mechanism, it should be discernible and analysable as an underlying structure in the form, iconography and purpose of works of art. Certain modes of art will manifest or express it more lucidly and abundantly than others. Satire and the Grotesque, which Goya adopts in his graphic Work, are especially fruitful in this regard. In both, one can find processes and states of degradation and vitiation that accord with the two facets of abjection Hal Foster (1996) so pragmatically terms the operation to abject and the condition to be abject. Satire, with its inclination to criticise political, social and ecclesiastical figures, can chiefly be interpreted in terms of the operation to abject (to lower, cast down, depose, sideline), while the Grotesque, displaying the distorted, monstrous, 'freakish', hybrid, impossible, relates more to tire condition to be abject. This conjunction between satire/the Grotesque and abjection guides my interpretation of Los Caprichos and Los Disparates. Los Caprichos, in which Goya took it upon himself to "censure" and "ridicule" "human errors and vices", are marked by a quite strict use of satire to criticise, mock and marginalise certain social groups (prostitutes, nobles and corrupt clerics, in particular). Since society, or the Symbolic that undergirds it, cannot do without the abject, either in its role as midden or as oppositional determinant or defining other, the satirical project cannot banish or destroy the abject; it can, however, bid and lobby for some degree of social reclamation and rejuvenation. The satirist depicts the grotesque, sordid, obscene, deviant, abandoned and licentious to indicate to the viewer/reader what s/h e must laugh off to live a decent, obedient, constructive and law-fearing life. Goya takes this aapproach in Los Caprichos. After all, in at least one letter to his friend Martin Zapater he hinted that he feared the "witches, goblins, phantoms, arrogant giants, knaves" and "scoundrels" of his society, and evidently felt a need to part from them. How deep this need ran one cannot say; many of his images suggest a degree of equivocation (he vacillates between being on the side of the law and on the side of Ms own more incorruptible conscience, from which he upbraids the law) and ambivalence (on the one hand, he scolds his objects of attack and appears to be repelled by them; on the other, he seems to relish depicting them in grotesque and blighted shapes, as if the satirical purpose is secondary to the opportunity his art provides to invent forms and get close to the forbidden, the anti-social, the rotten, the abject). In Los Disparates equivocation and ambivalence come more to the fore. Goya often appears most aggressively satirical in the Disparates when he questions corruption in social institutions such as tire Church and the law. Some images, notably Folhj of the Mass, juxtapose a wrathful figure with a mass of social ills, foibles and depravities, and seem characteristically satirical, but the majority of the etchings are striking in their lack of closure, as if a "state of unresolved tension", to quote Michael Steig, adequately rewarded Goya for the labour of production. Man xoandering among Phantoms, for example, is ambiguous and seems to sum up Goya's relationsMp to the abject toward the end of his life: through the surrogate of an old man, Goya appears to have struck a deal with the abject; submerged in it, corrupted by it, impure, but nevertheless sufficiently single-minded to find an identity separate from it. Complicit, but differentiated: all subjects stand in this way to the abject. In Los Desastres, especially given that I do not deal with the Caprichos Enfdticos section of the series, my interpretation is determined less by satire than by the question of how an antagonistic nation uses war as a mechanism of conclusive abjection to extend military, political and, ultimately. Symbolic influence - by means of sanctioned murder, execution, even rape - over another nation, w ith the aim of making that nation succumb to the abjection of surrender and the imposition of a foreign Symbolic. War also produces heaps of corpses and, in the occupied cities, ill and starving destitutes: those reduced to conditions of permanent or near-permanent abjection by war's ballistic exacerbation of the operation to abject. Contact with abjection through art strengthens, weakens and expands the self. It carries the threat of immersion in the repressed and the promise of risque pleasure - both from the diminution of unpleasure through the making or viewing of art, and the more positive pleasure of jouissance. Contact with abjection allows, further, for the complicated experience of being liminal, grotesque and abject oneself while caught between the poles of the Symbolic and tire abject. Whether we, as makers an d /o r viewers, criticise or joy in it, abjection holds out the alluring prospect of catharsis and temporary relief both from its own hazards and the rigours and inhibitions of social life. Goya, it would appear, found this intervenient condition compelling enough to return to it - if he ever truly left it - over a period of almost three decades through the medium of the three graphic series I explore in this dissertation.
224

Resistência à corrosão de amálgamas e de liga à base de gálio, sem e com adesivos, através do método de perda de peso e análise da rugosidade de superfície.

Abreu, Paulo Humaitá de 10 May 2002 (has links)
Avaliou-se a resistência à corrosão pelos testes de perda de peso em imersão alternada (solução-ar) e as conseqüentes alterações produzidas nas superfícies dos três materiais restauradores (os amálgamas Dispersalloy e Tytin Plus, ambos de alto conteúdo de cobre, respectivamente do tipo fase dispersa e do tipo partícula única, assim como a liga à base de gálio Galloy), não ou associados a dois sistemas adesivos (All-Bond 2 e PAAMA-2), observadas através da medição da rugosidade de superfície. Confeccionou-se dez corpos-de-prova, para cada condição específica, a partir de uma matriz metálica de aço inoxidável contendo cinco cavidades cilíndricas, com 10,7 mm de diâmetro por 3,0 mm de altura cada uma. Após o polimento, como é feito no caso de análises metalográficas, os espécimes foram pesados e levados ao rugosímetro para realizar as medições imediatamente. Estes foram submetidos à imersão alternada, na solução de sulfeto de sódio a 5 %, por um período de 24 horas e novamente foi realizada a pesagem e obtidos os valores de perda de peso. Depois da pesagem, os corpos-de-prova foram levados novamente ao rugosímetro para obtenção dos valores médios de rugosidade de superfície. Os resultados foram registrados e submetidos à análise de variância, a dois critérios, e ao teste de contrastes de Tukey-Kramer. Dos resultados obtidos, conclui-se que todos os espécimes perderam peso e tiveram sua rugosidade de superfície aumentada após a imersão em solução corrosiva; a liga Galloy mostrou valores maiores, tanto no método de perda de peso como no de rugosidade de superfície, quando comparada aos dois amálgamas; a liga Tytin Plus alcançou os melhores resultados; houve diferença estatisticamente significante entre os materiais restauradores, mas não entre os sistemas adesivos utilizados, mostrando comportamentos diferentes dependendo da combinação desses fatores. / The resistance to the corrosion was evaluated through weight loss to an alternated immersion (solution-air) and its consequent changes on the surface of three restoring materials (them amalgams Dispersalloy and Tytin Plus, both with high copper content, respectively dispersion phase and unique particle, as well as the alloy gallium base Galloy), associated or not to two adhesive systems (All-Bond 2 and PAAMA-2), observed by measuring the surface roughness. Ten bodies-of-test were made, for each specific condition, in a metallic matrix os stainlesss steel with five cilindrical cavities, measuring 10,7 mm in diameter and 3,0 mm thickness each one. After polishing, as in the metalographic anal ysis, the specimens were weighed and submitted to the roughness measurer to measuring inicial. These were submitted to an alternated immersion in 5 % sodium sulfide solution, for 24 hours and then the second weighting was performed and obtained the average values of weight loss. A second measure of the surface roughness was then performed. The results were registered and submitted to the variance analysis, to two approaches, and to the test of contrasts of Tukey-Kramer. From the obtained results, it was concluded that all specimens lost weight and there was an increasing roughness surface after immersion in corrosive solution; Galloy showed higher values, both weight loss test and the rougness surface, compared to two amalgams; the alloy Tytin Plus obtained better results; there was significant statistical difference among the restoring materials, but not among adhesive systems, showing different behaviors according to arrangement of these factors.
225

Paisagem-retrato retrato-paisagem - fragmentos de memórias da infância / Paisagem-retrato retrato-paisagem - fragmentos de memórias da infância

Alexandrino, Helena 20 October 2011 (has links)
Este trabalho consiste de paisagens e autorretratos, inspirados nas memórias de minha infância. Desenho, gravura e aquarela são os meios utilizados na realização de tais obras, que são acompanhadas por um texto escrito que busca, por sua vez, refletir sobre ou evocar esta memória. / This work consists of inner landscapes and self-portraits, inspired by my childhood memories. Drawing, printmaking and watercolor are the means used in carrying out such works, which are accompanaied by a written text that seeks, in turn, to reflect on or evoke this memory.
226

Solace: Intimately Remembered Places

Unknown Date (has links)
The culmination of my graduate research and investigations is my thesis exhibition Solace; Intimately Remembered Places. This body of paintings is a visual representation of land, water and flora that focuses on my abstraction of nature to extract essential elements that expresses my deep connection to a specific time and place, layered with associated memories. By revisiting a landscape over a sustained period of time, I developed a personal visual vocabulary to communicate the essential abstract forms of nature and record the subtle nuances of color, light, shape, texture, positive and negative space to evoke a particular time and place. I expanded my painting techniques through the addition of a laser cutter. Rooted in a background of graphic design, my thesis also incorporated and included a book form using similar strategies. / Includes bibliography. / Thesis (M.F.A.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection
227

Estudo da corrosão de Poli(N-vinilcarbazol), obtido via polimerização radical vivo. / Study of Poly(N-vinylcarbazole) etching, obtendet by \"living\" radical polymerization.

Taís Aparecida de Assis Garcia Moreira 27 May 2008 (has links)
O principal objetivo deste trabalho é a obtenção de trilhas com largura de dezenas de microns de Poli(N-vinilcarbazol) (PVK). Essas trilhas terão uma possível utilização em conjunto com outros materiais poliméricos como camada condutora na obtenção de um dispositivo semicondutor com material totalmente orgânico. O polímero escolhido foi o PVK, obtido a partir da síntese do monômero de N-vinilcarbazol, utilizando a técnica de polimerização radical livre viva, na presença do iniciador bimoleculares TEMPO (2,2,6,6-terametilpiperidinil-1-óxi)/BPO (peróxido de benzoíla) na razão molar 1:1,33. Além disso, a massa molar de 50.000g/mol para o PVK foi escolhida, previamente, devido às suas boas características elétricas condutoras, quando dopadas com perclorato de lítio. Para a remoção e definição de geometria do PVK foi usada a técnica de plasma etching por ser um processo limpo, de fácil manuseio e grande possibilidade de controle de parâmetros, além da possibilidade de usar diversos gases. Por outro lado, os parâmetros de corrosão, através de plasma de oxigênio foram modificados com a finalidade de obter uma condição ideal para o processo de remoção e em seguida o polímero foi caracterizado novamente, verificando as possíveis mudanças nas características físico-químicas resultante do processo. Testes com a corrosão em ambiente úmido com tolueno, também foram realizados para verificar as condições favoráveis e desfavoráveis nas técnicas de corrosão e as suas compatibilidades com os diversos materiais utilizados. Por fim, nas caracterizações elétricas e físico-químicas, geometrias pré-determinadas foram utilizadas para permitir estudos de parâmetros de análise, como a definição dos limites mínimos das geometrias, efeitos de borda, limite mínimo de largura de linha, taxa de remoção, excesso de remoção e a condutividade elétrica. / The main objective of this work is to obtain trails with ten microns width of Poly (N-vinylcarbazole) (PVK). These trails will have a possible use in set with other polymeric materials as conducting layer in the attainment of a device semiconductor with total organic material. The polymer studied was the PVK from the synthesis of vinylcarbazole monomer, using the method called living free radical in the presence of a bimolecular system of initiators BPO (benzoyl peroxide) and TEMPO (2,2,6,6-tetramethylpiperidinyloxy). The 50.000g/mol molar mass was used previously, resulted of its good conducting electric characteristics when doped with lithium percolate. To remove and to define the PVK geometry, the plasma technique was used because it is a clean, easy and rapid process, many possibility of parameters control and possibility to use several gas. Using oxygen plasma, the corrosion parameters had been modified to get the best condition to remove all PVK film without modifies the photoresist film. After the process, the polymer was characterized again to verify the possibility of changes in the physicist-chemistries characteristics of the PVK film. The wet corrosion using toluene had been made to verify the parameters and conditions in the techniques to remove the PVK films and its compatibilities with the other materials used as photoresist, aluminum etc. In the electric, optical and physicist-chemistries characterizations, some predetermined geometries had been used to study and to analyze parameters as the definition and the minimum limits of the geometries, effect of edge, the minimum width, the corrosion rate, excess of corrosion and the electric conductive.
228

Desenvolvimento de software para simulação atomística da corrosão anisotrópica do silício por autômato celular. / Software development for atomistic simulation of anisotropic etching silicion by cellular automata.

José Pinto de Oliveira Júnior 27 November 2008 (has links)
Nesse trabalho foi desenvolvido um software para simular a corrosão anisotrópica do silício, tendo como base o comportamento desta corrosão em soluções alcalinas (KOH). Esse software foi escrito na linguagem C++ para diversas plataformas e possui dois módulos básicos que são a Biblioteca de classes (denominada autosim) e uma Interface Gráfica (denominada AutoMEMS). A API desenvolvida possui classes que implementam 3 modelos de simulação da corrosão que se baseiam no modelo matemático do autômato celular, que são o Autômato Convencional, Estocástico e Contínuo. Por usar o autômato celular, permite realizar a simulação da corrosão do silício usando filme de mascaramento na frente e nas costas do substrato, os quais também podem conter geometrias arbitrárias. Além disso, a API implementa ferramentas de visualização que tem como objetivo, simplificar e representar as informações contidas nas matrizes de estados. Um exemplo de ferramenta de visualização é a ferramenta de detecção de contornos que analisa cada camada da matrizes e no final, cria todos os contornos encontrados. E por último, a biblioteca autosim fornece classes para a construção de outros autômatos celulares. A Interface Gráfica fornece ferramentas de desenhos para a construção de máscaras para as simulações e também, fornece ferramentas para configurar todos os parâmetros envolvidos na simulação. E por último, a Interface Gráfica visualiza todo o resultado da simulação numa janela gráfica 3D. O programa simula desde geometrias simples como quadrados, cruzes, L, cantilevers até geometrias mais complexas como uma estrutura de Wagon Wheel em formato de uma rosa dividida em ângulos de 1°. Também, permite definir matrizes de células de diversos tamanhos, desde matrizes pequenas (com 200x200x100 células) até matrizes gigantescas (com 4000x4000x100 células). Para matrizes pequenas, a simulação e detecção de contornos ocorre em tempo real, mas para matrizes maiores, esse tempo pode se estender a várias horas de processamento computacional, apesar de que, maiores quantidades de células melhoram a resolução da simulação. Todas as simulações realizadas possuem boa concordância com os resultados experimentais. Por exemplo, o aparecimento de cantos vivos convexos que ocorre na corrosão de uma ilha quadrada é prevista no simulador, o aparecimento de paredes inclinadas com orientação cristalográfica também é prevista pelo simulador de corrosão. / This work was developed a software for simulate the anisotropic etching silicon, based on the behavior this etch in alkaline solutions (KOH). The software was written in language C++ for various platforms and has two basic modules that are the library of classes (called autosim) and an Graphical Interface (called AutoMEMS). The API developed has classes that implement three models of etch simulation that based on mathematical model of cellular automata, that are the Conventional Automata, Stochastic and Continuous. To use the cellular automata, allows perform the anisotropic etching silicon simulation using masking film in front and back of substrate, which too may contain arbitrary geometrics. Also, the API implement tools of visualization that as objective, simplify and represent the informations contained in state matrix. A example of visualization tools is a tool of detection of contours that analyzes each layer of matrixs and in end, create all the contours found. And finally, the library autosim provides for construction of other cellular automatas. The Graphical Interface provides tools of drawing for construction of masks for simulations and too, provides tools for configure all parameters involved in simulation. And finally, a Graphical Interface view all the results of simulation in graphical window 3D. The software was simulation since simply geometries as square, cross, L, cantilevers until geometries more complex as a struture of Wagon Whell in format of a rose and divide in angle of 1° degree. Too, allows define matrixs of cells of various sizes, since small matrixs (with 200x200x200 cells) until big matrixs (with 4000x4000x100 cells). For small matrixs, the time of simulation and detection of contours is real-time, but, for big matrixs, this time can a several hours of computational processing, despite the fact that more quantities of cells improve the simulation resolution. All simulations fulfilled has good concordance with experimetals results, for example, the appearance of life corner convex that occurs in etching of island square and provided in simulator, the apperance of sloping walls with cristalographic orientation too and provided by simulator of etching.
229

Estudo da corrosão de Poli(N-vinilcarbazol), obtido via polimerização radical vivo. / Study of Poly(N-vinylcarbazole) etching, obtendet by \"living\" radical polymerization.

Moreira, Taís Aparecida de Assis Garcia 27 May 2008 (has links)
O principal objetivo deste trabalho é a obtenção de trilhas com largura de dezenas de microns de Poli(N-vinilcarbazol) (PVK). Essas trilhas terão uma possível utilização em conjunto com outros materiais poliméricos como camada condutora na obtenção de um dispositivo semicondutor com material totalmente orgânico. O polímero escolhido foi o PVK, obtido a partir da síntese do monômero de N-vinilcarbazol, utilizando a técnica de polimerização radical livre viva, na presença do iniciador bimoleculares TEMPO (2,2,6,6-terametilpiperidinil-1-óxi)/BPO (peróxido de benzoíla) na razão molar 1:1,33. Além disso, a massa molar de 50.000g/mol para o PVK foi escolhida, previamente, devido às suas boas características elétricas condutoras, quando dopadas com perclorato de lítio. Para a remoção e definição de geometria do PVK foi usada a técnica de plasma etching por ser um processo limpo, de fácil manuseio e grande possibilidade de controle de parâmetros, além da possibilidade de usar diversos gases. Por outro lado, os parâmetros de corrosão, através de plasma de oxigênio foram modificados com a finalidade de obter uma condição ideal para o processo de remoção e em seguida o polímero foi caracterizado novamente, verificando as possíveis mudanças nas características físico-químicas resultante do processo. Testes com a corrosão em ambiente úmido com tolueno, também foram realizados para verificar as condições favoráveis e desfavoráveis nas técnicas de corrosão e as suas compatibilidades com os diversos materiais utilizados. Por fim, nas caracterizações elétricas e físico-químicas, geometrias pré-determinadas foram utilizadas para permitir estudos de parâmetros de análise, como a definição dos limites mínimos das geometrias, efeitos de borda, limite mínimo de largura de linha, taxa de remoção, excesso de remoção e a condutividade elétrica. / The main objective of this work is to obtain trails with ten microns width of Poly (N-vinylcarbazole) (PVK). These trails will have a possible use in set with other polymeric materials as conducting layer in the attainment of a device semiconductor with total organic material. The polymer studied was the PVK from the synthesis of vinylcarbazole monomer, using the method called living free radical in the presence of a bimolecular system of initiators BPO (benzoyl peroxide) and TEMPO (2,2,6,6-tetramethylpiperidinyloxy). The 50.000g/mol molar mass was used previously, resulted of its good conducting electric characteristics when doped with lithium percolate. To remove and to define the PVK geometry, the plasma technique was used because it is a clean, easy and rapid process, many possibility of parameters control and possibility to use several gas. Using oxygen plasma, the corrosion parameters had been modified to get the best condition to remove all PVK film without modifies the photoresist film. After the process, the polymer was characterized again to verify the possibility of changes in the physicist-chemistries characteristics of the PVK film. The wet corrosion using toluene had been made to verify the parameters and conditions in the techniques to remove the PVK films and its compatibilities with the other materials used as photoresist, aluminum etc. In the electric, optical and physicist-chemistries characterizations, some predetermined geometries had been used to study and to analyze parameters as the definition and the minimum limits of the geometries, effect of edge, the minimum width, the corrosion rate, excess of corrosion and the electric conductive.
230

Desenvolvimento de software para simulação atomística da corrosão anisotrópica do silício por autômato celular. / Software development for atomistic simulation of anisotropic etching silicion by cellular automata.

Oliveira Júnior, José Pinto de 27 November 2008 (has links)
Nesse trabalho foi desenvolvido um software para simular a corrosão anisotrópica do silício, tendo como base o comportamento desta corrosão em soluções alcalinas (KOH). Esse software foi escrito na linguagem C++ para diversas plataformas e possui dois módulos básicos que são a Biblioteca de classes (denominada autosim) e uma Interface Gráfica (denominada AutoMEMS). A API desenvolvida possui classes que implementam 3 modelos de simulação da corrosão que se baseiam no modelo matemático do autômato celular, que são o Autômato Convencional, Estocástico e Contínuo. Por usar o autômato celular, permite realizar a simulação da corrosão do silício usando filme de mascaramento na frente e nas costas do substrato, os quais também podem conter geometrias arbitrárias. Além disso, a API implementa ferramentas de visualização que tem como objetivo, simplificar e representar as informações contidas nas matrizes de estados. Um exemplo de ferramenta de visualização é a ferramenta de detecção de contornos que analisa cada camada da matrizes e no final, cria todos os contornos encontrados. E por último, a biblioteca autosim fornece classes para a construção de outros autômatos celulares. A Interface Gráfica fornece ferramentas de desenhos para a construção de máscaras para as simulações e também, fornece ferramentas para configurar todos os parâmetros envolvidos na simulação. E por último, a Interface Gráfica visualiza todo o resultado da simulação numa janela gráfica 3D. O programa simula desde geometrias simples como quadrados, cruzes, L, cantilevers até geometrias mais complexas como uma estrutura de Wagon Wheel em formato de uma rosa dividida em ângulos de 1°. Também, permite definir matrizes de células de diversos tamanhos, desde matrizes pequenas (com 200x200x100 células) até matrizes gigantescas (com 4000x4000x100 células). Para matrizes pequenas, a simulação e detecção de contornos ocorre em tempo real, mas para matrizes maiores, esse tempo pode se estender a várias horas de processamento computacional, apesar de que, maiores quantidades de células melhoram a resolução da simulação. Todas as simulações realizadas possuem boa concordância com os resultados experimentais. Por exemplo, o aparecimento de cantos vivos convexos que ocorre na corrosão de uma ilha quadrada é prevista no simulador, o aparecimento de paredes inclinadas com orientação cristalográfica também é prevista pelo simulador de corrosão. / This work was developed a software for simulate the anisotropic etching silicon, based on the behavior this etch in alkaline solutions (KOH). The software was written in language C++ for various platforms and has two basic modules that are the library of classes (called autosim) and an Graphical Interface (called AutoMEMS). The API developed has classes that implement three models of etch simulation that based on mathematical model of cellular automata, that are the Conventional Automata, Stochastic and Continuous. To use the cellular automata, allows perform the anisotropic etching silicon simulation using masking film in front and back of substrate, which too may contain arbitrary geometrics. Also, the API implement tools of visualization that as objective, simplify and represent the informations contained in state matrix. A example of visualization tools is a tool of detection of contours that analyzes each layer of matrixs and in end, create all the contours found. And finally, the library autosim provides for construction of other cellular automatas. The Graphical Interface provides tools of drawing for construction of masks for simulations and too, provides tools for configure all parameters involved in simulation. And finally, a Graphical Interface view all the results of simulation in graphical window 3D. The software was simulation since simply geometries as square, cross, L, cantilevers until geometries more complex as a struture of Wagon Whell in format of a rose and divide in angle of 1° degree. Too, allows define matrixs of cells of various sizes, since small matrixs (with 200x200x200 cells) until big matrixs (with 4000x4000x100 cells). For small matrixs, the time of simulation and detection of contours is real-time, but, for big matrixs, this time can a several hours of computational processing, despite the fact that more quantities of cells improve the simulation resolution. All simulations fulfilled has good concordance with experimetals results, for example, the appearance of life corner convex that occurs in etching of island square and provided in simulator, the apperance of sloping walls with cristalographic orientation too and provided by simulator of etching.

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