Journal of Electronics Manufacturing最新文献

{"title":"MOISTURE ABSORPTION BY ENCAPSULATED MICROCHIP PACKAGES","authors":"F. Giacobbe","doi":"10.1142/S0960313100000149","DOIUrl":"https://doi.org/10.1142/S0960313100000149","url":null,"abstract":"This paper describes an experimental study that was designed to measure specific mass increases (due to the absorption of moisture) that occurred in selected pre-dried plastic encapsulated microchip packages (PEMs) exposed to moist air. Three different types of PEM packages were tested during the course of this work. Two of these PEM types were \"dummy\" ball grid arrays (BGAs) and plastic leaded chip carriers (PLCCs). The other PEMs tested were \"real\" metric plastic quad flatpack packages (MQFPs). Moisture absorption isotherms for all of the PEM types were measured at ambient temperatures and at relative humidity (RH) levels very near 50% and 100%. A theoretical method, based upon our experimental results, that could be used to predict moisture absorption behavior between 0 and 100% RH levels (at ambient temperatures) was also described. One result of this study was that nearly 50% of the moisture absorbed by selected pre-dried PEM specimens, during a 50 hr time period, occurred within the first 5 hr of the total exposure time. This fact indicates that even relatively short PEM exposure times, in very high RH environments, can be very serious with regard to the \"popcorning\" effect that may occur when moisture laden PEMs are reflow soldered onto printed wiring boards. The need to protect pre-dried, moisture sensitive, PEMs in dry air or in dry inert gas environments, prior to any high temperature assembly process, is clearly justified.","PeriodicalId":309904,"journal":{"name":"Journal of Electronics Manufacturing","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127004422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"LIFE CYCLE ASSESSMENT OF A TELECOMMUNICATIONS EXCHANGE","authors":"A. Andrae, U. Östermark, Johan Liu","doi":"10.1142/S0960313100000186","DOIUrl":"https://doi.org/10.1142/S0960313100000186","url":null,"abstract":"This paper describes a comparative life cycle assessment (LCA) of a new Business Communication 10 (BC10) and an old Business Communication 8 (BC8) model of the private branch exchange Modular Digital 110 (MD 110), designed and sold by Ericsson Enterprise AB (EE) and produced by Flextronics, in this case for the European Union (EU) market. LCA is a technique for assessing the environmental aspects and potential impact associated with a product’s whole life cycle from the “cradle to the grave”. The study meets the requirements of the standards International Organisation for Standardisation (ISO) 14040:1997 English (E), ISO 14041:1998 E and the draft standards ISO/Draft International Standard (DIS) 14042 and ISO/DIS 14043 and was critically reviewed by Henrik Wenzel, Instituttet for ProduktUdvikling (The Institute for Product Development, IPU) in Denmark. The modelling of the system includes manufacturing (hardware and EE’s organisation), use stage (electricity consumption), end-of-life (recycling processes) and transports. Electronic devices are modelled in depth (16 groups of components) and data from over 40 suppliers have been collected. EE’s organisation (development, marketing & sales, supply, installation, service and maintenance) is modelled for use of offices and business travelling. The following main conclusions of the project are based on results for potential contributions to the environmental impact categories acidification, global warming and eutrophication, which were chosen to be the most relevant. The environmental impact improvements of the new model compared to the old are approximately 10%, and the uncertainty of the results is judged to be smaller than the difference between the systems. \u0000The use stage and the manufacturing stage give the largest impacts, both for the new and the old model. In the manufacturing stage, the hardware production clearly dominates. EE’s organisation is secondly most important and hardware transport is least important. This is due to more environmental load from service and business travelling in the organisation than environmental load arising from the distribution of the product. The results predominantly reflect energy use, whereas toxicological aspects could not be reliably assessed due to lack of data and reliable methods and needs separate attention. The technology improvements shown for BC10 compared to BC8 only describe design improvements made by EE, and do not take into account potential technology production improvements made by component suppliers.","PeriodicalId":309904,"journal":{"name":"Journal of Electronics Manufacturing","volume":"111 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115789653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A review of microwave curing of polymer materials","authors":"Tiebing Wang, Johan Liu","doi":"10.1142/S0960313100000162","DOIUrl":"https://doi.org/10.1142/S0960313100000162","url":null,"abstract":"Polymer and polymer-based composites are widely used in the electronic packaging industry. There is a need to shorten the processing time for cost-effective reasons. Microwave radiation is recognized as an alternative to the conventional thermal treatment. This paper presents the fundamental concept of MW used as heating source for curing polymers. Upon literature survey, comparison between thermal and MW approaches was given. Various variables affecting MW applications were analyzed. Metal effect under microwave radiation was also discussed corresponding to the metal-filled electrically conductive adhesives. At last, a conclusion was made that microwave as the source of energy can offer higher processing rate than thermal treatment while no adverse effect is exerted on the properties of the processed materials; an even higher heating rate will require considerations of the influence of various variables; metal-filled electrically conductive adhesives could be heated with variable frequency microwave with no arcing being incurred.","PeriodicalId":309904,"journal":{"name":"Journal of Electronics Manufacturing","volume":"134 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116353620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"EXPERIMENTAL STUDY OF ACID COPPER ELECTROPLATING OF NON-UNIFORMLY PATTERNED SUBSTRATE","authors":"G. Poon, K. S. Chin, David J. Williams","doi":"10.1142/S0960313100000125","DOIUrl":"https://doi.org/10.1142/S0960313100000125","url":null,"abstract":"Factorial experiments were carried out to study the effects of the average cathodaic current density, electrode separation, and the active area density on the workpiece-level plating thickness variability for an acid copper pattern electroplating process. All the three parameters and the current density × electrode separation interaction were found to be significant, and an eight-term first-order prediction model was constructed and verified experimentally. The minimum variability achievable was found to increase with the active area density contrast over the board surface, and was explained by the scattering effect of the density contrast on the average plating thickness. Furthermore, these experiments showed that the pattern-level variation was different even though the two patterns have identical local average active area density and density contrast if their individual feature sizes are different. This suggested an interaction effect between the overall active area density and the density contrast of the substrate, and the possibility of further reducing the workpiece level variability by careful manipulation of such interaction.","PeriodicalId":309904,"journal":{"name":"Journal of Electronics Manufacturing","volume":"126 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115957921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"FLIP CHIP ON FR-4, CERAMICS AND FLEX","authors":"Z. Zhong, K. Goh","doi":"10.1142/S0960313100000095","DOIUrl":"https://doi.org/10.1142/S0960313100000095","url":null,"abstract":"This paper discusses flip chip on FR-4, ceramics and flex investigated in our research institution and the industry. The reliability performance of the processes of flip chip on FR-4 and ceramics using gold bumps with anisotropic conductive film or anisotropic conductive paste, and eutectic solder bumps with underfill epoxy was studied. Flip chip on ceramic substrate gives much better reliability than flip chip on FR-4 boards. Most of the samples assembled on ceramic boards using eutectic solder with underfill epoxy survived after 9,500 cycles of the thermal cycling test (-40°C to 125°C). Also, flip chip on FR-4 substrate using eutectic solder with underfill epoxy showed reasonable reliability performance. Flip chip on flex (FCOF) was also studied as FCOF can be the next generation of flex circuit packaging for cheaper and faster speed performance. The FCOF utilized eutectic solder bumps for the chip interconnection. Prototypes of the FCOF were assembled and their reliability was tested with satisfactory results.","PeriodicalId":309904,"journal":{"name":"Journal of Electronics Manufacturing","volume":"125 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116211648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ELECTRICAL CHARACTERIZATIONS OF ISOTROPIC CONDUCTIVE ADHESIVES (ICAs)","authors":"Y. Shimada, D. Lu, C. Wong","doi":"10.1142/S0960313100000083","DOIUrl":"https://doi.org/10.1142/S0960313100000083","url":null,"abstract":"Isotropic conductive adhesives (ICAs) have been developed as an alternative for traditional tin/lead (Sn/Pb) solders for electronics interconnect applications. Low processing temperature, elimination of lead, no-flux, no-clean process and the simple processing are some of the advantages of using ICAs. However, compared to the mature soldering technology, conductive adhesive technology is till in its infancy, and as such, there are some limitations for current commercial ICAs. Besides the conductivity fatigue and poor impact strength, electrically conductive adhesives tend to have lower current carrying capability and higher contact resistance in comparison to the conventional Sn/Pb solder. This is mainly due to the difference in the electrical conductive mechanisms between ICAs and Sn/Pb solders. This study focuses on current capacity measurements and other electrical properties, such as inductance, capacitance and resistance with a LCR meter and a four-point probe both in the direct current (DC) and alternating current (AC) ranges of the ICAs.","PeriodicalId":309904,"journal":{"name":"Journal of Electronics Manufacturing","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127562612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"METHODOLOGY FOR PREDICTING MANUFACTURING YIELD FOR PRINTED CIRCUIT BOARD ASSEMBLY LINES","authors":"Felipe Helo, K. Ellis, J. Kobza","doi":"10.1142/S0960313100000071","DOIUrl":"https://doi.org/10.1142/S0960313100000071","url":null,"abstract":"Engineers have few tools to reliably estimate their production capabilities as they introduce new board designs onto their current production lines. This paper presents a methodology to predict the manufacturing yield of a printed circuit board manufactured on a given assembly line. Current techniques for yield estimation are based on process modeling techniques and board design techniques, and the methodology presented in this paper integrates these two approaches. The combined yield methodology consists of a Poisson-based yield model that uses fault probabilities to estimate the yield and an optimization problem that generates the fault probabilities. The optimization problem determines the fault probabilities that minimize the difference between actual yield values and predicted yield values (using the past yield history and design information from various board designs). The resulting fault probabilities represent both component and process faults and are used in the Poisson-based yield model to estimate the yield. The methodology compared favorably with previous models published in the literature. In addition, the methodology is applied to two actual PCB assembly lines and predicts actual yield within 3% for the boards considered.","PeriodicalId":309904,"journal":{"name":"Journal of Electronics Manufacturing","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127075987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"MEASUREMENT OF INTERFACIAL FRACTURE TOUGHNESS FOR MICROELECTRONIC PACKAGES","authors":"Dickson T. S. Yeung, M. Yuen, D. Lam, P. Chan","doi":"10.1142/S0960313100000137","DOIUrl":"https://doi.org/10.1142/S0960313100000137","url":null,"abstract":"Interfacial adhesion plays an important role in the reliability of plastic encapsulated microelectronic (PEM) devices. Moisture that penetrates through the PEM devices and stays in the weak adhesion location vaporizes when the IC devices are subjected to thermal loading such as solder reflow in the assembly process. Device failures result due to pop-corning and cracking. Reliable PEM devices can be manufactured if there is good adhesion strength between packaging materials. In this paper, measurement and determination of interfacial fracture toughness between electronic materials are addressed. Interfacial fracture toughness between commercially available glob-top material and copper substrate is characterized. Laminated specimens with center pre-crack configuration are prepared and tested using four-point bending (FPB) configuration. The aim is to quantify the critical fracture load during crack initiation. Critical strain energy release rate and its corresponding mode mixity are determined from the measured critical load. Copper/glob-top material (Cu/GT) interface is selected as a case study and it is found that its interfacial fracture energy increases from 4 to 18J/m2 for loading phase angle ranging from 0° (pure mode I) to a mode mixity of 40°. The results will be presented in this paper.","PeriodicalId":309904,"journal":{"name":"Journal of Electronics Manufacturing","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132526591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Process design of microchip encapsulation : a case based reasoning with fuzzy retrieval approach","authors":"K. Tong, C. Kwong","doi":"10.1142/S0960313100000113","DOIUrl":"https://doi.org/10.1142/S0960313100000113","url":null,"abstract":"The microelectronic industry continues to grow rapidly in size and importance. The industry has already reached the size of other major industries with sales of product and equipment totalling billions of dollars a year. Among all the options available for semiconductor assembly, plastic packaging by using epoxy based encapsulation process is less expensive and accounts for approximately 80% of the worldwide packaging share and this percentage is increasing. Microchip encapsulation based on transfer molding is one of the important processes of semiconductor manufacturing. Quality is heavily dependent on the encapsulation mold design, selection of molding compound and process parameter setting of encapsulation molding. In current practice, encapsulation mold design and parameter setting of the transfer molding are done manually in a trial-and-error manner which would result in long lead time for obtaining acceptable molding quality. In this paper, an artificial intelligence technique, Case Based Reasoning with Fuzzy Retrieval, is described to perform process design of microchip encapsulation from which a case based system for microchip encapsulation, named CBS-ME, was developed. The system aims to automate the design of the key elements of encapsulation molds, suggest process parameters for transfer molding and improve its own design know-how through a learning process. A validation test was performed and the system solutions were benchmarked with the solutions obtained from the actual molding. Deviation of the two sets of solutions for mold design parameter setting and process parameter setting are 3.5% and 6% respectively.","PeriodicalId":309904,"journal":{"name":"Journal of Electronics Manufacturing","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122279620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"COMPONENT BASED PARADIGM FOR THE DESIGN AND IMPLEMENTATION OF CONTROL SYSTEMS IN ELECTRONICS MANUFACTURING MACHINERY","authors":"R. Harrison, A. West","doi":"10.1142/S0960313100000022","DOIUrl":"https://doi.org/10.1142/S0960313100000022","url":null,"abstract":"This paper describes a component based approach to the design, modelling and implementation of electronics manufacturing machines and their associated control systems that offers significant advantages over traditional methods. The new approach, which supports the implementation of machines utilising sequence and interlock based control is suitable for discrete parts handling and assembly applications. The external drivers of change effecting the electronic manufacturing sector are reviewed and the need for a better approach to the design and implementation of machines is explained within this context. Existing best practise for the implementation of electronics manufacturing machinery is described together with the role of current industry standards. A component based approach to control system design and implementation is described which is better aligned to today's business needs. This approach makes it possible for an accurate visualisation of machine behaviour to be made available to all interested parties throughout the machine lifecycle in a form that process engineers and users can easily relate to.","PeriodicalId":309904,"journal":{"name":"Journal of Electronics Manufacturing","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2000-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123728615","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}