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Characterization of Copper Electroplating And
CHARACTERIZATION OF COPPER ELECTROPLATING AND ELECTROPOLISHING PROCESSES FOR SEMICONDUCTOR INTERCONNECT METALLIZATION by JULIE MARIE MENDEZ Submitted in partial fulfillment of the requirements For the degree of Doctor of Philosophy Dissertation Advisor: Dr. Uziel Landau Department of Chemical Engineering CASE WESTERN RESERVE UNIVERSITY August, 2009 CASE WESTERN RESERVE UNIVERSITY SCHOOL OF GRADUATE STUDIES We hereby approve the thesis/dissertation of _____________________________________________________ candidate for the ______________________degree *. (signed)_______________________________________________ (chair of the committee) ________________________________________________ ________________________________________________ ________________________________________________ ________________________________________________ ________________________________________________ (date) _______________________ *We also certify that written approval has been obtained for any proprietary material contained therein. TABLE OF CONTENTS Page Number List of Tables 3 List of Figures 4 Acknowledgements 9 List of Symbols 10 Abstract 13 1. Introduction 15 1.1 Semiconductor Interconnect Metallization – Process Description 15 1.2 Mechanistic Aspects of Bottom-up Fill 20 1.3 Electropolishing 22 1.4 Topics Addressed in the Dissertation 24 2. Experimental Studies of Copper Electropolishing 26 2.1 Experimental Procedure 29 2.2 Polarization Studies 30 2.3 Current Steps 34 2.3.1 Current Stepped to a Level below Limiting Current 34 2.3.2 Current Stepped to the Limiting -
UNIT 5 MODERN MACHINING METHOD Method
Modern Machining UNIT 5 MODERN MACHINING METHOD Method Structure 5.1 Introduction Objectives 5.2 Working Principle of Energy 5.3 Non-conventional Machining Processes 5.4 Electrical Discharge Machining 5.5 Wire Cut Electric Discharge Machining 5.6 Ultrasonic Machining 5.7 Chemical Machining Processes 5.8 Electrochemical Machining 5.9 Laser Beam Machining 5.10 Plasma Arc Machining 5.11 Summary 5.12 Answers to SAQs 5.1 INTRODUCTION Modern machining methods are also named as non-conventional machining methods. These methods form a group of processes which removes excess material by various techniques involving mechanical, thermal, electrical chemical energy or combination of these energies. There is no cutting of metal with the help of metallic tool having sharp cutting edge. The major reasons of development and popularity of modern machining methods are listed below. (a) Need of machine newly developed metals and non-metals having some special properties like high strength, high hardness and high toughness. A material possing the above mentioned properties are difficult to be machined by the conventional machining methods. (b) Sometimes it is required to produce complex part geometries that cannot be produced by following conventional machining techniques. Non-conventional machining methods also provide very good quality of surface finish which may also be an encouragement to these methods. There can be a very long list of non-conventional machining methods. These methods can be classified as the basis of their base principle of working. Objectives After studying this unit, you should be able to understand introduction of modern machining methods and their difference with conventional machining methods, different classification criteria of modern machining methods and their classifications, and working principle, process details, applications and advantages and disadvantages machining. -
OVERVIEW of FOUNDRY PROCESSES Contents 1
Cleaner Production Manual for the Queensland Foundry Industry November 1999 PART 5: OVERVIEW OF FOUNDRY PROCESSES Contents 1. Overview of Casting Processes...................................................................... 3 2. Casting Processes.......................................................................................... 6 2.1 Sand Casting ............................................................................................ 6 2.1.1 Pattern Making ................................................................................... 7 2.1.2 Mould Making ..................................................................................... 7 2.1.3 Melting and Pouring ........................................................................... 8 2.1.4 Cooling and Shakeout ........................................................................ 9 2.1.5 Sand Reclamation .............................................................................. 9 2.1.6 Fettling, Cleaning and Finishing....................................................... 10 2.1.7 Advantages of Sand Casting............................................................ 10 2.1.8 Limitations ........................................................................................ 10 2.1.9 By-products Generated .................................................................... 10 2.2 Shell Moulding ........................................................................................ 13 2.2.1 Advantages...................................................................................... -
Fire Protection of Steel Structures: Examples of Applications
Fire protection of steel structures: examples of applications Autor(en): Brozzetti, Jacques / Pettersson, Ove / Law, Margaret Objekttyp: Article Zeitschrift: IABSE proceedings = Mémoires AIPC = IVBH Abhandlungen Band (Jahr): 7 (1983) Heft P-61: Fire protection of steel structures: examples of applications PDF erstellt am: 06.10.2021 Persistenter Link: http://doi.org/10.5169/seals-37489 Nutzungsbedingungen Die ETH-Bibliothek ist Anbieterin der digitalisierten Zeitschriften. Sie besitzt keine Urheberrechte an den Inhalten der Zeitschriften. Die Rechte liegen in der Regel bei den Herausgebern. Die auf der Plattform e-periodica veröffentlichten Dokumente stehen für nicht-kommerzielle Zwecke in Lehre und Forschung sowie für die private Nutzung frei zur Verfügung. Einzelne Dateien oder Ausdrucke aus diesem Angebot können zusammen mit diesen Nutzungsbedingungen und den korrekten Herkunftsbezeichnungen weitergegeben werden. Das Veröffentlichen von Bildern in Print- und Online-Publikationen ist nur mit vorheriger Genehmigung der Rechteinhaber erlaubt. Die systematische Speicherung von Teilen des elektronischen Angebots auf anderen Servern bedarf ebenfalls des schriftlichen Einverständnisses der Rechteinhaber. Haftungsausschluss Alle Angaben erfolgen ohne Gewähr für Vollständigkeit oder Richtigkeit. Es wird keine Haftung übernommen für Schäden durch die Verwendung von Informationen aus diesem Online-Angebot oder durch das Fehlen von Informationen. Dies gilt auch für Inhalte Dritter, die über dieses Angebot zugänglich sind. Ein Dienst der ETH-Bibliothek ETH Zürich, Rämistrasse 101, 8092 Zürich, Schweiz, www.library.ethz.ch http://www.e-periodica.ch J% IABSE periodica 2/1983 IABSE PROCEEDINGS P-61/83 69 Fire Protection of Steel Structures — Examples of Applications Protection contre le feu des structures acier — Quelques exemples d'applications Brandschutz der Stahlkonstruktionen — Einige Anwendungsbeispiele Jacques BROZZETTI Margaret LAW Dir., Dep. -
A Comparison of Thixocasting and Rheocasting
A Comparison of Thixocasting and Rheocasting Stephen P. Midson The Midson Group, Inc. Denver, Colorado USA Andrew Jackson Arthur Jackson & Co., Ltd. Brighouse UK Abstract The first semi-solid casting process to be commercialized was thixocasting, where a pre-cast billet is re-heated to the semi-solid solid casting temperature. Advantages of thixocasting include the production of high quality components, while the main disadvantage is the higher cost associated with the production of the pre-cast billets. Commercial pressures have driven casters to examine a different approach to semi-solid casting, where the semi-solid slurry is generated directly from the liquid adjacent to a die casting machine. These processes are collectively referred to as rheocasting, and there are currently at least 15 rheocasting processes either in commercial production or under development around the world. This paper will describe technical aspects of both thixocasting and rheocasting, comparing the procedures used to generate the globular, semi-solid slurry. Two rheocasting processes will be examined in detail, one involved in the production of high integrity properties, while the other is focusing on reducing the porosity content of conventional die castings. Key Words Semi-solid casting, thixocasting, rheocasting, aluminum alloys 22 / 1 Introduction Semi-solid casting is a modified die casting process that reduces or eliminates the porosity present in most die castings [1] . Rather than using liquid metal as the feed material, semi-solid processing uses a higher viscosity feed material that is partially solid and partially liquid. The high viscosity of the semi-solid metal, along with the use of controlled die filling conditions, ensures that the semi-solid metal fills the die in a non-turbulent manner so that harmful gas porosity can be essentially eliminated. -
Implementation of Metal Casting Best Practices
Implementation of Metal Casting Best Practices January 2007 Prepared for ITP Metal Casting Authors: Robert Eppich, Eppich Technologies Robert D. Naranjo, BCS, Incorporated Acknowledgement This project was a collaborative effort by Robert Eppich (Eppich Technologies) and Robert Naranjo (BCS, Incorporated). Mr. Eppich coordinated this project and was the technical lead for this effort. He guided the data collection and analysis. Mr. Naranjo assisted in the data collection and analysis of the results and led the development of the final report. The final report was prepared by Robert Naranjo, Lee Schultz, Rajita Majumdar, Bill Choate, Ellen Glover, and Krista Jones of BCS, Incorporated. The cover was designed by Borys Mararytsya of BCS, Incorporated. We also gratefully acknowledge the support of the U.S. Department of Energy, the Advanced Technology Institute, and the Cast Metals Coalition in conducting this project. Disclaimer This report was prepared as an account of work sponsored by an Agency of the United States Government. Neither the United States Government nor any Agency thereof, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any Agency thereof. The views and opinions expressed by the authors herein do not necessarily state or reflect those of the United States Government or any Agency thereof. -
Photochemical Machining
Design Guide to Photochemical Machining A World Apart in a World of Parts This “Design Guide to Photochemical Machining” was cre- ated for those involved with the designing or purchasing of Fotofab uses a special process called Photochemical Machining. Also known as chemical etching, acid etching, or milling, this process metal parts. While it provides general guidelines, Fotofab’s offers many advantages over traditional metal fabrication methods: Technical Sales Staff is available to assist Speed you with your specifi c requirements. • Tooling can be produced rapidly. • Parts can be produced and shipped within hours of receiving a print. By designing with an awareness of our process capabilities, you will minimize Flexibility • Many intricate part geometries, like those found in fi ne resolution the cost and delivery time of your metal screens, can be photochemically machined easily and economically. parts. We are ready to work with you, • Revisions to part designs are implemented quickly and inexpensively. • Brittle metals, which often fracture during conventional stamping, are machined without diffi culty. Just tell us what you need! Repeatability • Prototype and production quantities can be made using the same process and tooling. Contents • Extremely thin metal can be machined without distortion; dimensional accuracy actually increases as metal thickness decreases. The Fotofab Process • page 4 • Physical properties of the metal, such as hardness, strength and formability, are not changed by the process. Value-Added Services • page 7 • Magnetically soft materials can be fabricated while retaining their optimum permeability. Applications • page 8 • Parts are inherently free of burrs. Material Selection • page 10 Cost Effectiveness • Tooling and set-up costs are extremely low compared to hard tooling. -
Able Electropolishing
ELECTROPOLISHING THE FINAL STEP IN PROTOTYPING ENHANCING YOUR METAL PARTS FOR ACCELERATED SPEED TO MARKET CONTENTS 01 TECHNICAL SUMMARY 03 DIRECT METAL LASER SINTERING 05 INVESTMENT CASTING 07 PHOTOCHEMICAL MACHINING 09 METAL INJECTION MOLDING 11 ELECTRICAL DISCHARGE MACHINING 14 3D PRINTING 15 LASER CUTTING 17 METAL STAMPING 19 ABOUT ABLE ELECTROPOLISHING WHAT IS ELECTROPOLISHING? // WHAT IT DOES TECHNICAL SUMMARY While the process is best known for the bright polish left on a surface, there are some important, often overlooked, benefits of this metal finishing method. These benefits include deburr- ing, size control, microfinish improvement, ultraclean finishing, corrosion resistance and others. These metal improvement Electropolishing is often referred to as a “reverse plating” process. Electrochemical in nature, benefits are highly desirable to design and production engi- electropolishing uses a combination of rectified current and a blended chemical electrolyte neers for cost savings and product lifespan improvement. bath to remove flaws from the surface of a metal part. When speed to market is critical, electropolishing offers the necessary // HOW IT WORKS part enhancements needed in the final step of production. Figure 1 The typical electropolishing installation is deceptively Since the development of electropolishing in the 1950s, substantial refinements have taken similar to a plating line. A power source converts AC current place. Able has many electrolytes to allow for electropolishing on a broad range of metals. to DC at low voltages. A rubber-lined tank, usually fabricated These newer electrolytes, combined with advanced parts handling techniques, have improved from steel, is used to hold the chemical bath. production yields on a wide range of metal products. -
The MG Chemicals Professional Prototyping Process
The MG Chemicals Professional Prototyping Process Introduction ..................................................................................................................................................................3 Before you begin ..........................................................................................................................................................4 Read the instructions in their entirety.......................................................................................................................4 Get everything you need...........................................................................................................................................4 Plan for safety...........................................................................................................................................................5 Plan for disposal .......................................................................................................................................................5 Design your circuit for the MG process ...................................................................................................................6 Step 1: Cutting and Routing .........................................................................................................................................6 Ingredients required..................................................................................................................................................6 Overview: -
S2P Conference
The 9th International Conference on Semi-Solid Processing of Alloys and Composites —S2P Busan, Korea, Conference September 11-13, 2006 Qingyue Pan, Research Associate Professor Metal Processing Institute, WPI Worcester, Massachusetts Busan, a bustling city of approximately 3.7 million resi- Pusan National University, in conjunction with the Korea dents, is located on the Southeastern tip of the Korean Institute of Industrial Technology, and the Korea Society peninsula. It is the second largest city in Korea. Th e natu- for Technology of Plasticity hosted the 9th S2P confer- ral environment of Busan is a perfect example of harmony ence. About 180 scientists and engineers coming from 23 between mountains, rivers and sea. Its geography includes countries attended the conference to present and discuss all a coastline with superb beaches and scenic cliff s, moun- aspects on semi-solid processing of alloys and composites. tains which provide excellent hiking and extraordinary Eight distinct sessions contained 113 oral presentations views, and hot springs scattered throughout the city. and 61 posters. Th e eight sessions included: 1) alloy design, Th e 9th International Conference on Semi-Solid Pro- 2) industrial applications, 3) microstructure & properties, cessing of Alloys and Composites was held Sept. 11-13, 4) novel processes, 5) rheocasting, 6) rheological behavior, 2006 at Paradise Hotel, Busan. Th e fi ve-star hotel off ered a modeling and simulation, 7) semi-solid processing of high spectacular view of Haeundae Beach – Korea’s most popular melting point materials, and 8) semi-solid processing of resort, which was the setting for the 9th S2P conference. -
Un-Conventional Metal Surfacing with Conductive Coating
Journal of Material Science and Mechanical Engineering (JMSME) p-ISSN: 2393-9095; e-ISSN: 2393-9109; Volume 5, Issue 2; April-June, 2018 pp. 77-82 © Krishi Sanskriti Publications http://www.krishisanskriti.org/Publication.html Un-conventional Metal Surfacing with Conductive Coating Sulabh Kumar1 and Vaneet Bhardwaj2 1Department of Mechanical Engineering, Sharda University, Greater Noida (UP) India 2Department of Mechanical Engineering, Sharda University, Greater Noida, U.P, India E-mail: [email protected], [email protected] Abstract—As we know that in day-to-day life electricity has become These types of carbon brush holders are being used in basic need of the people. To produce electricity, stress is directly put generator based upon rating of the generator and type of slip over the natural resources like fossil fuels, water, metals by means of ring used because width of rings in the slip ring and diameter either hydraulic power generation or thermal power generation and (outer diameter) of slip ring is the deciding factor for selection in this era, we also generate by nuclear power. To achieve the need of type of carbon brush holder. For example, if the width of of power generation, the setup to produce electricity consists of rotor, stator, different types of windings such as stator winding, rotor ring of slip ring is 10.05 mm then carbon brush of width 10.05 winding, slip rings, carbon brush holder and different types of mm can only be used neither lesser nor bigger. Thus, pocket connections. Several metals and chemicals are used to electroplate size of carbon holder must be of 10.05 mm which means the carbon brush holder such as copper, brass, CuSO4, H2SO4. -
Chemical Machining and Milling
CHEMICAL MACHINING AND MILLING Introduction Chemical machining (CM) is the controlled dissolution of workpiece material (etching) by means of a strong chemical reagent (etchant). In CM material is removed from selected areas of workpiece by immersing it in a chemical reagents or etchants; such as acids and alkaline solutions. Material is removed by microscopic electrochemical cell action, as occurs in corrosion or chemical dissolution of a metal. This controlled chemical dissolution will simultaneously etch all exposed surfaces even though the penetration rates of the material removal may be only 0.0025–0.1 mm/min. The basic process takes many forms: chemical milling of pockets, contours, overall metal removal, chemical blanking for etching through thin sheets; photochemical machining (pcm) for etching by using of photosensitive resists in microelectronics; chemical or electrochemical polishing where weak chemical reagents are used (sometimes with remote electric assist) for polishing or deburring and chemical jet machining where a single chemically active jet is used. A schematic of chemical machining process is shown in Figure 6. Figure 6: (a) Schematic of chemical machining process (b) Stages in producing a profiled cavity by chemical machining (Kalpakjain & Schmid) Chemical milling In chemical milling, shallow cavities are produced on plates, sheets, forgings and extrusions. The two key materials used in chemical milling process are etchant and maskant. Etchants are acid or alkaline solutions maintained within controlled ranges of chemical composition and temperature. Maskants are specially designed elastomeric products that are hand strippable and chemically resistant to the harsh etchants. Steps in chemical milling Residual stress relieving: If the part to be machined has residual stresses from the previous processing, these stresses first should be relieved in order to prevent warping after chemical milling.