Building a novel nanofabrication system using MEMS

Micro-electromechanical systems (MEMS) are electrically controlled micro-machines which have been widely used in both industrial applications and scientific research. This technology allows us to use macro-machines to build micro-machines (MEMS) and then use micro-machines to fabricate even smaller structures, namely nano-structures. In this thesis, the concept of Fab on a Chip will be discussed where we construct a palette of MEMS-based micron scale tools including lithography tools, novel atomic deposition sources, atomic mass sensors, thermometers, heaters, shutters and interconnect technologies that allow us to precisely fabricate nanoscale structures and conduct in-situ measurements using these micron scale devices. Such MEMS devices form a novel microscopic nanofabrication system that can be integrated into a single silicon chip. Due to the small dimension of MEMS, fabrication specifications including heat generation, patterning resolution and film deposition precision outperform traditional fabrication in many ways. It will be shown that one gains many advantages by doing nano-lithography and physical vapor deposition at the micron scale. As an application, I will showcase the power of the technique by discussing how we use Fab on a Chip to conduct quench condensation of superconducting Pb thin films where we are able to gently place atoms upon a surface, creating a uniform, disordered amorphous film and precisely tune the superconducting properties. This shows how the new set of techniques for nanofabrication will open up an unexplored regime for the study of the physics of devices and structures with small numbers of atoms

The Boston University Photonics Center annual report 2013-2014

This repository item contains an annual report that summarizes activities of the Boston University Photonics Center in the 2013-2014 academic year. The report provides quantitative and descriptive information regarding photonics programs in education, interdisciplinary research, business innovation, and technology development. The Boston University Photonics Center (BUPC) is an interdisciplinary hub for education, research, scholarship, innovation, and technology development associated with practical uses of light.This annual report summarizes activities of the Boston University Photonics Center in the 2013–2014 academic year.This has been a good year for the Photonics Center. In the following pages, you will see that the center’s faculty received prodigious honors and awards, generated more than 100 notable scholarly publications in the leading journals in our field, and attracted $14.5M in new research grants and contracts this year. Faculty and staff also expanded their efforts in education and training, through National Science Foundation–sponsored sites for Research Experiences for Undergraduates and for Teachers. As a community, we hosted a compelling series of distinguished invited speakers, and emphasized the theme of Innovations at the Intersections of Micro/Nanofabrication Technology, Biology, and Biomedicine at our annual Future of Light Symposium. We took a leadership role in running national workshops on emerging photonic fields, including an OSA Incubator on Controlled Light Propagation through Complex Media, and an NSF Workshop on Noninvasive Imaging of Brain Function. Highlights of our research achievements for the year include a distinctive Presidential Early Career Award for Scientists and Engineers (PECASE) for Assistant Professor Xue Han, an ambitious new DoD-sponsored grant for Multi-Scale Multi-Disciplinary Modeling of Electronic Materials led by Professor Enrico Bellotti, launch of our NIH-sponsored Center for Innovation in Point of Care Technologies for the Future of Cancer Care led by Professor Cathy Klapperich, and successful completion of the ambitious IARPA-funded contract for Next Generation Solid Immersion Microscopy for Fault Isolation in Back-Side Circuit Analysis led by Professor Bennett Goldberg. These three programs, which represent more than$20M in research funding for the University, are indicative of the breadth of Photonics Center research interests: from fundamental modeling of optoelectronic materials to practical development of cancer diagnostics, from exciting new discoveries in optogenetics for understanding brain function to the achievement of world-record resolution in semiconductor circuit microscopy. Our community welcomed an auspicious cohort of new faculty members, including a newly hired assistant professor and a newly hired professor (and Chair of the Mechanical Engineering Department). The Industry/University Cooperative Research Center—the centerpiece of our translational biophotonics program—continues to focus on advancing the health care and medical device industries, and has entered its fourth year of operation with a strong record of achievement and with the support of an enthusiastic industrial membership base

From Cleanroom to Desktop: Emerging Micro-Nanofabrication Technology for Biomedical Applications

This review is motivated by the growing demand for low-cost, easy-to-use, compact-size yet powerful micro-nanofabrication technology to address emerging challenges of fundamental biology and translational medicine in regular laboratory settings. Recent advancements in the field benefit considerably from rapidly expanding material selections, ranging from inorganics to organics and from nanoparticles to self-assembled molecules. Meanwhile a great number of novel methodologies, employing off-the-shelf consumer electronics, intriguing interfacial phenomena, bottom-up self-assembly principles, etc., have been implemented to transit micro-nanofabrication from a cleanroom environment to a desktop setup. Furthermore, the latest application of micro-nanofabrication to emerging biomedical research will be presented in detail, which includes point-of-care diagnostics, on-chip cell culture as well as bio-manipulation. While significant progresses have been made in the rapidly growing field, both apparent and unrevealed roadblocks will need to be addressed in the future. We conclude this review by offering our perspectives on the current technical challenges and future research opportunities

The Boston University Photonics Center annual report 2013-2014

This repository item contains an annual report that summarizes activities of the Boston University Photonics Center in the 2013-2014 academic year. The report provides quantitative and descriptive information regarding photonics programs in education, interdisciplinary research, business innovation, and technology development. The Boston University Photonics Center (BUPC) is an interdisciplinary hub for education, research, scholarship, innovation, and technology development associated with practical uses of light.This annual report summarizes activities of the Boston University Photonics Center in the 2013–2014 academic year.This has been a good year for the Photonics Center. In the following pages, you will see that the center’s faculty received prodigious honors and awards, generated more than 100 notable scholarly publications in the leading journals in our field, and attracted $14.5M in new research grants and contracts this year. Faculty and staff also expanded their efforts in education and training, through National Science Foundation–sponsored sites for Research Experiences for Undergraduates and for Teachers. As a community, we hosted a compelling series of distinguished invited speakers, and emphasized the theme of Innovations at the Intersections of Micro/Nanofabrication Technology, Biology, and Biomedicine at our annual Future of Light Symposium. We took a leadership role in running national workshops on emerging photonic fields, including an OSA Incubator on Controlled Light Propagation through Complex Media, and an NSF Workshop on Noninvasive Imaging of Brain Function. Highlights of our research achievements for the year include a distinctive Presidential Early Career Award for Scientists and Engineers (PECASE) for Assistant Professor Xue Han, an ambitious new DoD-sponsored grant for Multi-Scale Multi-Disciplinary Modeling of Electronic Materials led by Professor Enrico Bellotti, launch of our NIH-sponsored Center for Innovation in Point of Care Technologies for the Future of Cancer Care led by Professor Cathy Klapperich, and successful completion of the ambitious IARPA-funded contract for Next Generation Solid Immersion Microscopy for Fault Isolation in Back-Side Circuit Analysis led by Professor Bennett Goldberg. These three programs, which represent more than$20M in research funding for the University, are indicative of the breadth of Photonics Center research interests: from fundamental modeling of optoelectronic materials to practical development of cancer diagnostics, from exciting new discoveries in optogenetics for understanding brain function to the achievement of world-record resolution in semiconductor circuit microscopy. Our community welcomed an auspicious cohort of new faculty members, including a newly hired assistant professor and a newly hired professor (and Chair of the Mechanical Engineering Department). The Industry/University Cooperative Research Center—the centerpiece of our translational biophotonics program—continues to focus on advancing the health care and medical device industries, and has entered its fourth year of operation with a strong record of achievement and with the support of an enthusiastic industrial membership base

Friction-induced nanofabrication method to produce protrusive nanostructures on quartz

In this paper, a new friction-induced nanofabrication method is presented to fabricate protrusive nanostructures on quartz surfaces through scratching a diamond tip under given normal loads. The nanostructures, such as nanodots, nanolines, surface mesas and nanowords, can be produced on the target surface by programming the tip traces according to the demanded patterns. The height of these nanostructures increases with the increase of the number of scratching cycles or the normal load. Transmission electron microscope observations indicated that the lattice distortion and dislocations induced by the mechanical interaction may have played a dominating role in the formation of the protrusive nanostructures on quartz surfaces. Further analysis reveals that during scratching, a contact pressure ranged from 0.4Py to Py (Py is the critical yield pressure of quartz) is apt to produce protuberant nanostructures on quartz under the given experimental conditions. Finally, it is of great interest to find that the protrusive nanostructures can be selectively dissolved in 20% KOH solution. Since the nanowords can be easily 'written' by friction-induced fabrication and 'erased' through selective etching on a quartz surface, this friction-induced method opens up new opportunities for future nanofabrication

Caracterização do estresse mecânico de nanoestruturas de silício tensionado por espectroscopia Raman

Orientadores: José Alexandre Diniz, Marcos Vinicius Puydinger dos SantosDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de ComputaçãoResumo: A engenharia de silício tensionado provou ser uma tecnologia de sucesso para manter a lei de Moore e apresenta um grande potencial para o seu uso em nós tecnológicos altamente estressados e ainda menores na microeletrônica do futuro. Essa tarefa demanda o uso de técnicas de caracterização do estresse mecânico para o desenvolvimento e pesquisa em semicondutores. Uma potencial ferramenta de caracterização que permite a medição do estresse no silício de forma quantitativa é a espectroscopia Raman. Esse método de caracterização consiste em uma técnica não destrutiva e bem estabelecida que permite a caracterização do estresse com uma resolução espacial abaixo de 1 ?m e não requer procedimentos complexos de preparação da amostra. Contudo, estudos sobre o comportamento do deslocamento Raman em estruturas altamente tensionadas (tensão maior que 2 GPa) com dimensão crítica menor que 100 nm são escassos na literatura, sendo um gargalo para o uso de medidas Raman de forma sistemática em dispositivos tecnológicos futuros. Aqui, foi investigado o comportamento do estresse em função do deslocamento Raman da superfície de silício (001) de nanofios suspensos ultra finos (15 nm de espessura) e altamente tensionados com estresses na faixa de 0 ¿ 6.3 Gpa ao longo da direção cristalográfica [110]. O uso de nanofios ultrafinos como plataforma de estudo , ao longo da direção cristalográfica [110], permitiu a investigação sistemática de um bloco essencial que pode estar presente nos canais de transistores nMOS futuros. Alêm disso, essa plataforma suspensa atingiu valores de tensão ultra altos (até 6.3GPa) sem atuadores externos, permitindo pela primeira vez o estudo sistemático do comportamento da espectrocopia Raman em nanofios altamente tensionados. Os estresses foram medidos por simulações de elementos finitos (FEM) como forma de atingir uma grande precisão na caracterização da tensão. Então, medidas Raman experimentais foram realizadas seguidas de um protocolo de correção térmica para extrair o pico Raman corrigido livre de efeitos térmicos. O coeficiente de deslocamento do estresse (SSC) extraído, para baixa tensão (abaixo de 4.5 GPa), estava em boa concordância com alguns valores de SSC da literatura. Para maiores valores de tensão (maior que 4.5 GPa), demonstrou-se, pela primeira vez, que a relação linear deslocamento Raman - estresse não ocorre, requerendo uma correção empírica do modelo que está sendo proposta neste trabalho. Esses resultados demonstram a viabilidade da técnica Raman para caracterização do estresse de nanofios de silício ultrafinos, no qual deve ser útil para caracterizar nanodispositivos de silício tensionado para nós tecnológicos abaixo dos 100 nm sujeitos a uma faixa ampla de tensão, contribuindo para um tópico importante na indústria de semicondutoresAbstract: Strained silicon engineering has proven to be a successful technology to keep Moore¿s law and presents a great potential for its use in even smaller and highly stressed technological nodes in microelectronics in the future. Such a task demands the use of stress characterization techniques for semiconductor research and development. One potential characterization tool which makes possible quantitative stress measurement of silicon is the Raman spectroscopy. This characterization method is a wellestablished non-destructive technique that permits stress characterization with a spatial resolution of below 1 ?m and does not require complex sample preparation procedure. However, studies on Raman shift behavior of highly stressed structures (stress greater than 2 GPa) with the critical dimension smaller than 100 nm are scarce in the literature, being a bottleneck for the systematic use of Raman measurements in future technological devices. Here, it was investigated the Raman shift-stress behavior from the (001) silicon surface of highly strained ultra-thin (15 nm-thick) suspended nanowires with stresses in the range of 0 ¿ 6.3 GPa along the [110] direction. The use of ultrathin nanowires as a platform of study, along the [110] crystallographic direction, allowed the systematic investigation of one essential block that might be present in future nMOS transistors channels. Furthermore, this suspended platform reached ultra-high stress values (up to 6.3 GPa) without external actuators, allowing for the first time the systematic study of the Raman stress behavior of highly stressed nanowires. The stresses were evaluated by finite element method (FEM) simulations to achieve great accuracy in the stress characterization. Then, experimental Raman measurements were performed, followed by a thermal correction protocol to extract the corrected Raman peak free of thermal effects. The extracted stress shift coefficient (SSC), for lower stresses (below 4.5 GPa), was in good agreement with some of the SSC values in literature. For higher stresses (greater than 4.5 GPa), it was demonstrated, for the first time, that the linear shift Raman - stress relation does not hold, thus requiring an empirical model correction proposed in this work. The results demonstrate the feasibility of the Raman technique for the stress characterization of ultra-thin silicon nanowires, which should be useful to characterize strained silicon nanodevices for technological nodes below 100 nm under a wide range of stresses, contributing to such an important topic in the semiconductor industryMestradoEletrônica, Microeletrônica e OptoeletrônicaMestre em Engenharia Elétrica2018/02598-4FAPES