Author: Vahid RastegarPublisher:
ISBN:
Category : Materials science
Languages : en
Pages : 250
Book Description
Abrasive Particle Trajectories and Material Removal Non-Uniformity During CMP and Filtration Characteristics of CMP Slurries - A Simulation and Experimental Study
Author: Vahid RastegarPublisher:
ISBN:
Category : Materials science
Languages : en
Pages : 250
Book Description
Slurry Abrasive Particle Agglomeration Experimentation and Modeling for Chemical Mechanical Planarization (CMP)
Author: Joy Marie JohnsonPublisher:
ISBN:
Category :
Languages : en
Pages : 188
Book Description
A theoretical modeling approach is developed to predict silica-specific instability in chemical-mechanical polishing (CMP) slurries. In CMP, the formation of large agglomerates is of great concern, as these large particles are associated with high defectivity and poor polishing performance. The proposed model describes the complex CMP slurry system as a colloid under high non-linear shear conditions. The model diverges from the classic colloidal models by focusing on the following: reaction limited agglomeration (RLA) bounded by silica-specific modes of transitory bonding, and modified DVLO assumptions to include chemical activation and hydrodynamic agglomerate break-up condition evaluation. In order to build physical intuition and predict key model parameters, fundamental studies and novel metrology of agglomerates is performed.
Mechanical Aspects of the Material Removal Mechanism in Chemical Mechanical Polishing (CMP)
Author: Yongsik MoonA Study on Material Detachment Mechanism in CMP Process
Author: Wei ChePublisher:
ISBN:
Category :
Languages : en
Pages : 144
Book Description
Chemical Mechanical Polishing (CMP) is becoming an integral processing step in multilevel metallization designs for integrated circuit (IC) manufacturing. CMP is a process for surface planarization, aided by the combined actions of the chemical etching and mechanical polishing. It provides the needed local die planarization and global wafer surface uniformity. However, the material removal mechanisms (MRM) in the CMP process are not well understood, and the theoretical models for prediction of material removal rate (MRR) are not fully developed. The objective of this research is to study the surface material removal mechanisms in ductile materials during this micro and nano- polishing process, and develop mechanistic MRR models to optimize the process parameters. In the current framework, the abrasion process of pure copper surfaces is studied by a cross-scratch experiment in the micro scale regime. The experimentally measured force profiles are analyzed and compared to the deformation patterns from the SEM micrographs and surface profile. It is found that there is no net surface material removal along the trench formation. However, we observed that material is detached near the intersection between two scratches. It is speculated that for ductile surfaces, the deformation mechanism changes from ploughing mode to shearing mode as the indenter approaches the intersection of two scratches. The characteristic length of the detached segment is found to be proportional to the indentation depth. This finding is further clarified by FEM results and Molecular Dynamics simulations in our group. A mechanism based MRR model is then developed for CMP process. The predicted material removal rates are comparable to the experiment data.
Great Saturday
Author: Particle Scale Modeling of Material Removal and Surface Roughness in Chemical Mechanical Polishing
Author: Suresh Babu YeruvaPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The predictions of the model show a reasonable agreement with the experimental data. The model is validated for oxide and metal CMP systems. The PERC II model not only predicts the overall removal rate, but also the surface roughness of the polished wafer in selected systems. The developed model can be used to optimize the current CMP systems and provide insights into future CMP endeavors.
Face-up Chemical Mechanical Polishing
Author: Marvin Bryan ShiehPublisher:
ISBN:
Category :
Languages : en
Pages : 54
Book Description
A working prototype face-up CMP tool has successfully been completed. Experiments conducted on the face-up CMP machine qualitatively correspond with the theoretical polishing model. Discrepancies in data from the theoretical model could potentially be caused by non-uniform loading of the polishing pad and uneven distribution of slurry over the pad due to the edge effects on fluid flow. Despite the discrepancies, experimental data suggest that the theoretical model used to describe blanket wafer polishing by the face-up CMP tool is at least partially valid.
Synergy Between Chemical Dissolution and Mechanical Abrasion During Chemical Mechanical Polishing of Copper
Author: Wei ChePublisher:
ISBN:
Category :
Languages : en
Pages : 282
Book Description
Chemical mechanical planarization (CMP) is becoming a promising mainstream semiconductor processing method because of its demonstrated capability to achieve better local and global planarization for various materials. However, the CMP process is influenced by a set of factors, which lead to a poor understanding of the material removal mechanisms (MRMs) and inhibits the migratability of the lab-scale experiments to industrial practice. This work focuses on the synergistic effects between chemical dissolution and mechanical abrasion to understand the MRMs during CMP. Initial in-situ wear test in chemically active slurry showed an increased material removal rate (MRR) relative to dry wear tests. To understand the synergistic effects, two plausible MRMs; (i) chemical dissolution enhanced mechanical abrasion and (ii) mechanical abrasion accelerated chemical dissolution, were investigated. In addition, a phenomenological MRR model based on scratch-intersections was formulated to understand the role of consumables and the process parameters. For mechanism I, a combined experimental and modeling technique was devised to understand the mechanical properties of the soft layer formed on the surface due to chemical exposure in CMP. The developed approaches utilized nano-scratch tests, nano-dynamic mechanical analysis (DMA) tests, the limit analysis solution of surface plowing under a spherical traveling indenter, and finite element simulation to deconvolute the soft layer thickness, hardness and elastic modulus. For mechanism II, it is found that the residual stress caused by the mechanical wear enhances the chemical etching rate, as manifested by an increase in wear depth. It is also found that the roughness with wavelength above a critical value grows while roughness of lower wavelength decays during etching, in which an established fact for stress-enhanced chemical dissolution is used. The developed understanding would enable understanding the root causes of defect generation mechanism and render remedies for yield improvements. The proposed models, through their mechanistic description, will facilitate an exploration of the design space and identification of realistic CMP process domains, including: (i) particle shape, size and concentration; (ii) adapting slurry chemistry for required rates of chemical dissolution and mechanical abrasion; and (iii) selecting pads with the proper surface morphology and stiffness.
Chemical-Mechanical Polishing 2001 - Advances and Future Challenges:
Author: Suryadevara V. BabuPublisher: Cambridge University Press
ISBN: 9781107412187
Category : Technology & Engineering
Languages : en
Pages : 306
Book Description
With copper and barrier-layer integration firmly in place, several other exciting developments are occurring in the practice of chemical-mechanical polishing (CMP), and many advances are described in this book, first published in 2001. Discussions on CMP for shallow-trench isolation, abrasive-free slurries, improvements in pad and tool configurations including fixed abrasive pads, 'engineered' particles, effects of nanotopography, end-point studies, defect characterization and novel post-CMP cleaning methods are highlighted. Considerable progress has also been reported in modeling the complicated interactions that occur between the wafer surface and the pad and the slurry, whether containing abrasives or abrasive-free, and their influence on dishing and erosion and nonuniformity. These studies offer valuable insights for process improvements and yet many challenges remain and will provide a high level of interest for future books. Topics include: recent developments - pads and related issues; CMP abrasives; copper CMP/STI and planarization; STI and planarization - wear-rate models; low-k and integration issues - particle and process effects in CMP and issues in CMP cleaning.
Chemical Mechanical Planarization-Related to Contaminants
Author: Jihoon SeoPublisher:
ISBN:
Category : Electronic books
Languages : en
Pages : 0
Book Description
Chemical mechanical planarization (CMP) process has been widely used to planarize a variety of materials including dielectrics, metal, and semiconductors in Si-based semiconductor devices. It is one of the most critical steps to achieve the nanolevel wafer and die scale planarity. However, various contaminants are observed on the wafer surfaces after the CMP process, and they become the most critical yield detractor over many generations of rapidly diminishing feature sizes because they have the most direct impacts on device performance and reliability. This book chapter provides (1) CMP consumables-induced contaminants such as residual particles, surface residues, organic residues, pad debris and metallic impurities, pad contamination, watermark, etc., (2) brush-induced cross-contamination during post CMP cleaning, (3) post-CMP cleaning for removing these contaminants. Fundamental understanding of the formation of various types of CMP contaminants and their characteristics will significantly benefit the development of next-generation CMP slurries and post-CMP cleaning solutions.