Chemical Mechanical Planarization (CMP) is one of the most critical processing steps that enables fabrication of multilevel interconnects. The success of CMP process is limited by the implementation of an optimized process and reduction of process generated defects along with post CMP surface characteristics such as dishing and erosion. This thesis investigates to identify various sources of defects and studies the effect of factors that can be used to optimize the process. The major contributions of this work are: Understanding the effect of temperature rise on surface tribology, electrochemistry and post CMP pattern effects during the CMP process; investigating the effect of pad conditioning temperature and slurry flow rate on tribology and post CMP characteristics; development of novel slurries using polymer hybrid particles and improvement in slurry metrology to reduce surface damage during CMP. From the current research, it was shown that the effect of temperature on CMP tribology is predominantly affected by the polishing parameters and the polishing pad characteristics more than the chemical nature of the slurry. The effect of temperature is minimal on the resulting surface roughness but the with-in die non-uniformity is significantly affected by the temperature at the interface. Secondly, in this research it was shown that the effectiveness and aggressiveness of the pad conditioning process is highly influenced by the conditioning temperature. This aspect can be utilized to optimize the parameters for the pad conditioning process. Further, post CMP characteristics such as dishing, erosion and metal loss on patterned samples were shown to decrease with increase in slurry flow rate. This research then concentrates on the development of novel low defect slurry using polymer hybrid abrasive particles. Several varieties of surface functionalized polymer particles were employed to make oxide CMP slurries. These novel slurries proved to be potential candidates to reduce surface damage during CMP as they resulted in low coefficient of friction and much less surface scratches as compared to conventional abrasives. Thus, this research helps to reduce defects and non-planarity issues during CMP process thereby improving yield and reducing the cost of ownership.

Wear is an important phenomenon that occurs in all the polymer applications in one form or the other. However, important links between materials properties and wear remain illusive. Thus optimization of material properties requires proper understanding of polymer properties. Studies to date have typically lacked systematic approach to all polymers and wear test developed are specific to some polymer classes. In this thesis, different classes of polymers are selected and an attempt is made to use multiple scratch test to define wear and to create a universal test procedure that can be employed to most of the polymers. In each of the materials studied, the scratch penetration depth s reaches a constant value after certain number of scratches depending upon the polymer and its properties. Variations in test parameters like load and speed are also studied in detail to understand the behavior of polymers and under different conditions. Apart from polystyrene, all the other polymers studied under multiple scratch test reached asymptotes at different scratch numbers.

Este trabalho apresenta uma metodologia para inspeção de lentes oftalmológicas orgânicas esféricas durante seu processo de polimento. A metodologia consiste na obtenção de uma imagem em uma câmera de vídeo CCD, usando-se luz ultravioleta, da lente a ser inspecionada, e posterior processamento desta imagem para discriminar a presença de riscos de outros artefatos que poderão aparecer na imagem capturada. Para a detecção da presença de riscos foram utilizados os descritores de Fourier. Atenção especial foi dada à iluminação da lente, que é fator determinante na obtenção de uma boa qualidade de imagem. Os resultados mostram a eficiência do método e permitem sua utilização durante o processo de fabricação de lentes. / This work presents a methodology for inspection of spherical organic ophthalmic lenses during the polishing process. The methodology encompasses the capture of an ultraviolet image of the lens under inspection by a CCD video camera and associated processing of the image to discriminate between scratches on the lens and artifacts that can appear on the image. Fourier descriptors were used to detect the existence of scratches. Special attention was given to illumination which is a determining factor in grabbing an image with good quality. The results show that the method is efficient and that it can be used in the lens manufacturing process.

Ce travail de thèse porte sur l’étude des mécanismes physico-chimiques mis en jeu lors du polissage mécano-chimique du Zerodur® (vitrocéramique) par un abrasif à base d’oxydes de cérium. Les défauts obtenus à l’issu du polissage ont été caractérisés en microscopie optique et par microscopie à force atomique (AFM). Il en ressort deux principales populations, à savoir des rayures de type « fines » (longitudinales et continues) causées par des débris de matière polie. La seconde est la typologie « rayure éclat » (fractures perpendiculaires au sens de la rayure) causées par des agglomérats d’abrasif. Des analyses en spectroscopie RX de l’abrasif montrent une augmentation du ratio Ce3+/Ce4+ après la phase de polissage, confirmant la part chimique du polissage du Zerodur®. Des analyses de potentiel zêta ont été menées sur ces mêmes abrasifs et montrent une évolution de la charge de surface des particules abrasives. Des observations AFM montrent que plus la part Ce4+ est importante et meilleure est la qualité finale de la surface polie. La surface polie a également été sondée en ToF-SIMS. Il en ressort la présence d’une couche enrichie en cérium de plusieurs dizaines de nanomètres, lieu de la réaction mécano-chimique de polissage. Plus précisément, cette réaction semble avoir lieu dans la phase vitreuse du Zerodur®. / This PhD work focuses on the study of the physicochemical mechanisms involved in the chemical-mechanical polishing of Zerodur® (glass-ceramics) with an abrasive based on cerium oxides. The defects observed after polishing were characterized by optical microscopy and atomic force microscopy (AFM). Two main populations were observed, namely "fine" (longitudinal and continuous stripes) caused by debris of polished material. The second is called "scratch" (perpendicular fractures) caused by abrasive agglomerates. RX spectroscopic analyzes of the abrasive showed an increase in the Ce3+/ Ce4+ ratio after the polishing phase. This point confirms the chemical part of Zerodur® polishing. Zeta potential analyzes were carried out on these same abrasives and show an evolution of the abrasive surface charge. AFM observations show that the higher the Ce4+ concentration, the better the final polished surface quality. The polished surface was also probed with ToF-SIMS analyzes. This shows the presence of a cerium-enriched layer of several tens of nanometers, which may be a site for the chemical-mechanical polishing reaction. More precisely, this reaction seems to take place in the glassy phase of Zerodur®.

Este trabalho apresenta uma metodologia para inspeção de lentes oftalmológicas orgânicas esféricas durante seu processo de polimento. A metodologia consiste na obtenção de uma imagem em uma câmera de vídeo CCD, usando-se luz ultravioleta, da lente a ser inspecionada, e posterior processamento desta imagem para discriminar a presença de riscos de outros artefatos que poderão aparecer na imagem capturada. Para a detecção da presença de riscos foram utilizados os descritores de Fourier. Atenção especial foi dada à iluminação da lente, que é fator determinante na obtenção de uma boa qualidade de imagem. Os resultados mostram a eficiência do método e permitem sua utilização durante o processo de fabricação de lentes. / This work presents a methodology for inspection of spherical organic ophthalmic lenses during the polishing process. The methodology encompasses the capture of an ultraviolet image of the lens under inspection by a CCD video camera and associated processing of the image to discriminate between scratches on the lens and artifacts that can appear on the image. Fourier descriptors were used to detect the existence of scratches. Special attention was given to illumination which is a determining factor in grabbing an image with good quality. The results show that the method is efficient and that it can be used in the lens manufacturing process.

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