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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

Effect of Coated Material on Cu Wire Bonding in IC Package

Jhuang, Yun-Da 04 September 2012 (has links)
Wire bonding has been used in integrated circuit packaging for many decades because of its high reliability and performance. The most common metal used has been gold, but with the surge in commodity prices of gold in recent years, copper wire is now used to altered gold wire for cost saving. Many challenges have to be solved to meet its application requirement; coating is one of the applications. In this study, a 3D coated copper wire and coated Al pad is built by finite element method to simulate ultrasonic bonding and thermosonic bonding. To consider the effect of coated material to stress and strain field on ultrasonic bonding and the effect of coated material to temperature field on thermosonic bonding. Then use the Taguchi experiment method to discuss the effect on Cu-Ball and Al pad under different coated material and thickness combination. The results show that with coated material on Al pad or copper wire could reduce more than 48% of effective plastic strain after the bonding process, it obviously reduce the Al splash phenomenon in copper wire bonding. But the coated material such like palladium and nickel which have lower thermal conductivity would resist the heat transfer. And the Taguchi experiment method shows that the most effective way to reduce the effective stress during impact stage and ultrasonic vibration stage is to increase the thickness of palladium and nickel respectively, and when the thickness of coated material Au reached 0.01£gm could increase the temperature of Cu-Ball and Al pad mostly.
202

An analytical and experimental investigation for an interstitial insulation technology

Kim, Dong Keun 15 May 2009 (has links)
An insulation technique has been developed which contains a single or combination of materials to help minimize heat loss in actual industrial applications. For the petroleum industry, insulation for deep sea piping is one of the greatest challenges which would prevent the industry from meeting the high demand for oil through exploration into deeper ocean environments. At current seafloor depths (5,000~10,000ft), pipeline insulation is essential in preventing pipeline blockage resulting from the solidification of paraffin waxes and / or hydrate formation which exist in crude oil. To maintain crude oil temperatures above the paraffin solidification point (68°C or 155°F), new and better insulation techniques are essential to minimize pipeline heat loss and maintain crude oil temperatures. Therefore, the objective of this investigation was to determine whether or not the thermal resistance of a new insulation concept, which involves IIT (Interstitial Insulation Technology) with screen wire, was greater than existing readily available commercial products through analytical modeling and experimentation. The model takes into account both conforming and nonconforming interfaces at the wire screen contacts within the interstitial space between coaxial pipes. In addition, confirmation was needed to determine whether or not laboratory testing of simulated coupons translate to thermal performance for a prototype pipe segment that fabricated with two layers of low conductivity wire-screen (stainless steel) as the interstitial insulation material. Both the inner and outer surface temperatures of the coaxial pipes were measured in order to evaluate the effective thermal conductivity and thermal diffusivity of the insulation concept. The predicted results from the model compared very favorably with the experimental results, confirming both the trends and magnitudes of the experimental data. In other words, whether the reduction in heat transfer observed for small laboratory samples was realistic for application to a pipeline configuration. This effort involved both analytical modeling for all thermal resistances and experimental test runs for validation of the analytical model. Finally, it was a goal of this investigation to develop a simplified model for a multilayer composite structure which will include radiation heat transfer exchange among the layers that constitute the insulation. With the developed model, feasibility and performance characteristics of the insulation concept were predicted. The thermal predictions have demonstrated the thermal competitiveness of the interstitial insulation technology.
203

none

Chen, Fu-Te 26 July 2006 (has links)
Abstract not only influence on development of basic industries in a country but relate with business cycle. Hi-tech industries grow rapidly and play a key role with ¡§innovation¡¨ in stock market. The trends of hi technology make people forget that traditional industries not only keep existing but play a great role of economic activities. Historically speaking, Electric wire and cable industries still exist and even stably develop.¡C I hope to apply the following theories including innovation management, dependence of resources and product life cycle to explain why traditional industries are not sunset industries. Besides, I also chose Feng-chin Corporation as a case with best skills at magnet wire manufacturing to explain how a company keeps his competitive advantages in the matured market. Through case study and theory applied, the followings are concluded. 1. With less possibilities the products are replaced, the greater possibilities of continuity of the industry. In aspects of attributes of product itself, no alternatives appear to substitute for the copper and therefore the magnet wire industry would not disappear as the raw materials with the copper. Even though we can find the new material to replace the copper, the magnet wire industry will still exist with other alternative to replace the copper. When PLC model are applied, the products with greater continuity represent highly matured products. Hence, the products with greater continuity have the following characteristics including less possibilities to be replaced, highly matured and unclear decline stage, and high dependence of the below companies. 2. In low value added industries, individual company should emphasize on process innovation and diversified customers. The Feng-chin Corporation struggles to innovate technologically and in process by the following ways. (1) They make traditional products into hi-technology industries by raise added values. (2) They concentrate on costing down and their own field (3) They well utilize their resources to enforce the mutual-depend relationship with the below companies. Likewise, in the industries which pursue economic scales to reduce the cost, it is more important to diversify the costumers when they have the following characteristics including high matured products, high pricing products and lower mobility of the equipments. Key words: innovation management product life cycle magnet wire industry continuity
204

The Effect of Chloride Ion and Copper Oxide Layer on Plastic-encapsulated Package Reliability

Huang, Sheng-Tzung 20 June 2001 (has links)
None
205

Wire and column modeling

Mandal, Esan 30 September 2004 (has links)
The goal of this thesis is to introduce new methods to create intricate perforated shapes in a computing environment. Modeling shapes with a large number of holes and handles, while requiring minimal human interaction, is an unsolved research problem in computer graphics. In this thesis, we have developed two methods for interactively modeling such shapes. Both methods developed create perforated shapes by building a framework of tube like elements, such that each edge of a given mesh is replaced by a pipe. The first method called Wire modeling replaces each edge with a pipe that has a square cross-section. The result looks like a shape that is created by a framework of matchsticks. The second method, called Column modeling allows more rounded cross-sections for the pipes. The cross-sections can be any uniform polygon, and the users are able to control the number of the segments in the cross-section. These methods are implemented as an extension to an existing modeling system guaranteeing that the pipes are connected and the resulting shape can be physically constructed. Our methods require an initial input mesh that can either be imported from a commercially available software package, or created directly in this modeling system. The system also allows the users to export the models in obj file format, so that the models can be animated and rendered in other software packages.
206

Evaluation of the Thermal Performance for a Wire Mesh/Hollow Glass Microsphere Composite Structure as a Conduction Barrier

Mckenna, Sean 15 January 2010 (has links)
An experimental investigation exploring the use of wire mesh/hollow glass microsphere combination for use as thermal insulation was conducted with the aim to conclude whether or not it represents a superior insulation technology to those on the market. Three primary variables, including number of wire mesh layers, filler material, and temperature dependence were studied using an apparatus that was part of L.I.C.H.E.N (LabVIEW Integrated Conduction Heat Experiment Network), a setup whose basic components allow three vertically stacked samples to be thermally and mechanically controlled. Knowing the temperature profile in the upper and lower samples allows for determination of thermal conductivity of the middle material through the use of Fourier?s law. The numbers of layers investigated were two, four, six, and eight, with each separated by a metallic liner. The filler materials included air, s15, s35 and s60HS 3MTM hollow glass microspheres. The experiments were conducted at four temperatures of 300, 330, 366, and 400K with an interface pressure of 20 Psi. The experimental results indicated the ?number of layers? used was the primary factor in determining the effective thermal conductivity value. The addition of hollow glass microspheres as filler material resulted in statistically insignificant changes in effective thermal conductivity. Increasing the number of wire mesh layers resulted in a corresponding increase in effective thermal conductivity of the insulation. Changes in temperature had little to no effect on thermal conductivity. The effective thermal conductivity values for the proposed insulation structure ranged from 0.22 to 0.65 W/m-K, the lowest of which came from the two layer case having air as filler material. The uncertainties associated with the experimental results fell between 10 to 20 percent in all but a few cases. In the best performing cases, when compared with existing insulation technologies, thermal conductivity was approximately 3 to 10 times higher than these methods of insulation. Thus, the proposed insulation scheme with hollow glass-sphere filler material does not represent superior technology, and would be deemed uncompetitive with those readily available in the insulation market.
207

Taiwan enamel-insulated wire enterprise will develop the analysis in the future of Taiwan enameled wire enterprises - - take F Corporation as an example

Zhan, Zhi-qing 25 June 2008 (has links)
From the origin of enameled wire has been nearly a hundred years, Nowadays copper prices in the international market fluctuation as well as profession competition more and more intense.How to running an enamel-insulated wire enterprise is a topic which is worth discussing.. The enameled wire industry develops over 40 years in Taiwan, and sells mainly in the domestic market and export supplement, over years sells showing the stable growth.. Although Taiwan enamel-insulated wire's enterprise passes in and out innumerably, but the overall industry's development still underwent the long time not to fade. So long as can treat in this industry down the enterprise holds certain profit ability, in which reason makes one ponder. This study will use the world, the mainland and Taiwan enameled wire market analysis, will take F Corporation as the example to make the analysis to enameled wire enterprise's future development. Also will choose the list enameled wire enterprise in Taiwan to do the concrete research quite. This research hope that by ¡§Five Forces Model¡¨ and ¡§the SWOT analysis¡¨ the analysis, attempts to clear off the enamel-insulated wire enterprise's development direction. The research results show that the enameled wire industry is one approaches raw material the industry, in the next 10 years is difficult to be replaced. The enamel-insulated wire enterprise was one still held competitiveness which certain profit but managed to be getting more and more intense at present, business events' flexible also non-former days could compare. and enameled wire enterprises still maintain. Therefore the enamel-insulated wire enterprise's management should in grasps in the flexible foundation to do to the enterprise advantageous operation. Moreover enamel-insulated wire enterprise successful key aspect in cost management and high value added product development.
208

A Study of the Influence of Plasma Cleaning Process on Mechanical and Electrical Characteristics of Gold, Aluminum and Platinum Pads

Huang, Han-Peng 10 September 2008 (has links)
To improve the wire bondability, interfacial adhesion and popcorn cracking resistance in the packaging processing of IC and MEMS chips, this thesis utilized oxygen and helium plasmas to modify and clean the surface of metal pads. The influences of the plasma cleaning time, metal pad materials and wire bonding time/temperature/power on the strength of wire bonding were investigated. Two different wire materials (Al wire with 32 £gm in diameter and Au wire with 25 £gm in diameter) were bonded on the surface of Al, Au and Pt metal pads using a commercial ultrasonic wire bonder (SPB-U688), respectively. The pull strength detection of the implemented micro joints is characterized by an accurate pull strength testing system (Dage SERIES-4000). Based on hundred measurement results, this research has three conclusions described as follows. (I) The pull strength of Au pad is higher than that of Al and Pt pads no matter with the plasma cleaning process or not. The maximum pull strength (12.286 g) can be achieved as the surface of Au pad was modified by the helium plasma for 180 seconds. (II) Helium plasma cleaned wafer can obtain larger improvement of pull strength than that of the oxygen plasma under the same plasma time. However, this result can not be concluded in Al and Pt pads. (III) The optimized wire bonding time/power of the Au, Al and Pt pads are 0.07 s/2.1, 0.05 s/0.6 W and 0.03 s/2.7 W, respectively.
209

Orientation effects on Cu wire bonding by finite element method

Shih, Hsin-Chih 20 July 2009 (has links)
Ball bonding with gold wire has been the preferred choice to connect semiconductor chip and a lead frame. Recently, copper wires have been increasingly used to replace gold wires because of the rising price of gold. However, copper is harder than gold and has the tendency to induce the damage of bond pad or other underlying layers. Herein, Al pad material has to be changed from bulk to single crystal with (100) surface orientation in order to improve bonding reliability. Firstly, finite element method was adopted to simulate 3D wire bonding. Also, from the impact of gold wire bonding, the stress concentration was found on pad and underlying layers due to the higher elastic modulus of bulk Al. During copper ball impact, there is not only the serious stress concentration at pad, but also a pad splash due to the insufficient strength of bulk Al, even though bulk Al has a lower elastic modulus. Secondly, material properties of Al(100) were obtained by uniaxial tensile tests at constant speed. With molecular dynamics method, the incorporated result showed that Al(100) has the lower elastic modulus and higher yield strength than those of bulk material. Finally, single crystal Al(100) was used, instead of bulk material, to carry out copper ball impact process by using multi-scale simulation. Al(100) material is able to transform impact energy into the resilience of strain energy effectively owing to its high yield stress and low elastic modulus. Results show that the application of Al(100) material reduces the effects of stress concentration and pad ¡§splashing¡¨ successfully during copper ball impact process.
210

Phénomènes électro-dynamiques action mutuelle des fils conducteurs de courans électriques /

Guérin, Roch-Théodore. January 1900 (has links)
Thèse : Physique : Paris, Faculté des sciences : 1828. / Titre provenant de l'écran-titre.

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