106 research outputs found

    Polishing of CVD-Diamond Substrates Using Reactive Ion Etching

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    Multichip modules (MCM)have proved to be a viable packaging technology for achieving small size and high performance. By their nature, MCMs typically integrate multiple bare die into a module that can be the plastic or ceramic package. As a result, the MCMrequires an efficient mechanism for removing excess heat. Diamond with its excellent thermal conductivity, is the ideal choice as a substrate material for these applications. Chemical vapor deposited (CVD) diamond substrates makes possible the practical realization of a novel diamond based 3-D MCM. However, the diamond films grown by CVD technique are polycrystalline and have non-uniform filmroughness and randomly faceted crystals. These non-planar surfaces reduce the diamond\u27s thermal management efficiency. Therefore, itbecomes imperative that the asdeposited diamond films be polished for use inMCMs. Chemical assisted mechanical polishing (CAMP) technique has been developed at HiDEC,University of Arkansas. In this technique diamond is lapped against an alumina plate under a load in the presence of certain chemicals. Although CAMP technique reduces the lapping time considerably, stillnewer techniques must be developed to reduce polishing cost further. We are currently using reactive ion etching (RIE) to substantially reduce the polishing time. Preliminary studies using reactive ion etching showed etch rates of 500 - lOOOA/min at low pressures. These etched films showed a considerably higher polishing rate (using CAMP technique) than the nonetched films. Changes in the morphology and structure of the diamond films due to etching and polishing were characterized by scanning electron microscopy (SEM), Dektak profilometer and Raman spectroscopy. This paper presents a systematic study ofRIEand CAMP of CVD-diamond substrates

    Method of planarizing polycrystalline diamonds, planarized polycrystalline diamonds and products made therefrom

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    A method of planarizing a diamond film which generally includes orifices in the surface is described. The method includes first polishing the diamond film surface to reduce the surface roughness. A filler material is applied to the surface of the film to fill the orifices in the film. The film is polished to remove excess filler material and expose the diamond film surface. Also disclosed are planarized diamond films diamond substrate having a polished surface of both diamond and filler material and a variation in thickness of less than 8 percent

    Method of electroplating a substrate, and products made thereby

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    Disclosed is an electroplating method and products made therefrom, which in one embodiment includes using a current density to form a conductive metal layer having a surface roughness no greater than the surface roughness of the underlying member. In another embodiment of electroplating a substrate surface having peaks and valleys, the method includes electroplating a conductive metal onto the peaks to cover the peaks with the conductive metal, and into the valleys to substantially fill the valleys with the conductive metal

    Passivation of material using ultra-fast pulsed laser

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    The surface of a semiconductor material, e.g., gallium arsenide, is passivated by irradiating the surface with ultra-short laser pulses, until a stable passive surface is achieved. The passive surface so prepared is devoid of a superficial oxide layer

    Apparatus for and method of polishing and planarizing polycrystalline diamonds, and polished and planarized polycrystalline diamonds and products made therefrom

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    Disclosed are polished and planarized diamond films and a method and apparatus for polishing and planarizing diamond films. The method generally includes mechanical polishing of the diamond film against a ceramic surface in the presence of a treating agent of potassium nitrate and a polishing agent of potassium hydroxide. The produced films have an average surface roughness on the order of 0.05 microns, a planarization uniformity within eight percent, and are relatively free of process-induced contaminants

    (Re)pensando a perturbação de hiperatividade com défice de atenção: contributos de um estudo de caso

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    A Perturbação de Hiperatividade e Deficit de Atenção (PHDA) constitui uma temática atual no âmbito das problemáticas do desenvolvimento da infância e adolescência, não só pelo número crescente de casos, mas também pelo facto de a etiologia ainda ser desconhecida. A família constitui o núcleo educativo fundamental que acompanha o desenvolvimento da criança. Neste contexto, destacamos as práticas parentais, as interações e os vínculos afetivos, fatores relevantes no quadro do funcionamento familiar e parental. Apresentamos ao longo deste trabalho diversas questões relativas à PHDA, repensando a sua conceptualização, a análise diferencial e a influência que este tipo de perturbação tem no contexto familiar. Trata-se de um estudo de caso, em que a temática é conhecer o funcionamento familiar e parental numa família com uma criança diagnosticada com PHDA. Assim sendo, os objetivos delineados foram: i) conhecer o funcionamento parental e familiar ao nível das interações e dinâmicas da família, níveis de stress e rede de suporte social; ii) perceber os vínculos estabelecidos entre a criança e os pais; iii) conhecer os problemas de comportamento da criança ao longo do desenvolvimento e na atualidade; iv) analisar as perceções dos pais perante os problemas de comportamento. Para a prossecução do estudo, os instrumentos utilizados foram: a análise documental, o APGAR familiar; a observação naturalista; o Índice de Stress Parental e a entrevista. As conclusões emergentes relacionam-se com a evolução positiva dos comportamentos da criança; a aceitação da problemática por parte do pai, em contraponto com a não-aceitação por parte da mãe; a presença de sentimentos de baixa de autoconfiança/ autoestima; os sentimentos de fraca competência parental; os estilos parentais distintos e a fraca articulação educativa entre progenitores, bem como as diferentes estratégias parentais para o controlo do comportamento da criança.The Hyperactivity Disorder and Attention Deficit (ADHD) is a current theme in the context of the problems of childhood and adolescence development, not only by the increasing number of cases, but also by the fact that the etiology remains unknown. The family is the fundamental core educational accompanying the child's development. In this context, we emphasize parenting practices, interactions and emotional bonds, relevant factors within the family and parental functioning. We present throughout this work several issues related to ADHD, rethinking its conceptualization, differential analysis and the influence that this type of disturbance is in the family context. This is a case study, where the theme is to know the family and parental functioning in families with a child diagnosed with ADHD. Therefore, the outlined objectives were: i) to know the parental family functioning and the level of interaction and family dynamics, stress levels and social support; ii) understand the links established between the child and parents; iii) know the child's behavior problems throughout the development and nowadays; iv) examine parental perceptions before behavioral problems. For further study, the instruments used were: document reviews, the family APGAR; naturalistic observation; Parental Stress Index and the interview. Emerging findings relate to the positive development of children's behavior; acceptance of the problem by the parent as opposed to the non-acceptance by the mother; the presence of feelings of low self-confidence / self-esteem; feelings of poor parenting skills; the different parenting styles and poor educational link between parents and the different parenting strategies for child behavior contro

    Improving relationships between sales and marketing: the relative effectiveness of cross-functional coordination mechanisms

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    The importance of effective sales and marketing working relationships is well known and this article examines the effectiveness of various coordination mechanisms used to improve this cross-functional relationship. Six coordination mechanisms are measured to identify their effect on sales and marketing conflict and collaboration, which in turn influence business performance. The results reveal that not all coordination mechanisms are equally effective. Structuring sales and marketing as a single unit and creating cross-functional project teams improve the interface, as do providing opportunities for job rotation and establishing cross-functional meetings. However, employing cross-functional training and co-locating sales and marketing do not influence this working relationship. Finally, reducing conflict and increasing collaboration between sales and marketing is shown to independently, and positively, influence business performance
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