2017 21st European Microelectronics and Packaging Conference (EMPC) & Exhibition最新文献

{"title":"The transmittance properties of optical adhesives in humid environmental aging","authors":"S. Lahokallio, J. Kiilunen, L. Frisk","doi":"10.23919/EMPC.2017.8346865","DOIUrl":"https://doi.org/10.23919/EMPC.2017.8346865","url":null,"abstract":"In this paper optical properties of optical adhesives exposed to high humidity aging are investigated. The properties were studied using transmittance measurements. Both silicone-based and epoxy-based adhesives were studied. The transmittance properties of the silicone-based adhesives did not impair even after 1,200h of high humidity aging at 85°C and 85% relative humidity. Epoxy-based adhesives were seen to impair due to high humidity aging, but there were differences between the adhesives. Additionally, the curing temperature was found to play a role in the performance of the epoxy-based optical adhesives.","PeriodicalId":329807,"journal":{"name":"2017 21st European Microelectronics and Packaging Conference (EMPC) & Exhibition","volume":"590 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131290832","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":"Mathematical model of the process of creating film resistors with a Ni-P resistive layer","authors":"P. Kowalik, Z. Pruszowski","doi":"10.23919/EMPC.2017.8346911","DOIUrl":"https://doi.org/10.23919/EMPC.2017.8346911","url":null,"abstract":"The authors created a convenient and easy to use tool for calculating basic Ni-P resistive layer parameters, namely surface resistance and TCR of test resistor, based on chemical metallization parameters. The program allows calculating basic values characterizing the technological process of Ni-P resistive layer formation by means of chemical metallization. The values are temperature and acidity of the metallization bath. The values are calculated for a given level of surface resistance of Ni-P resistive layer and defined required range of changes of TCR of test resistor with the Ni-P layer. The calculations are possible for surface resistance values in the range of 0.5 Ω/□ □ 2.5 Ω/□. As the program was developed on the basis of experimental data, parameters of resistors produced using the mathematical model are in practice coherent with expected results. The best coherence is achieved for simultaneous simulation of surface resistance and TCR. Very good results are also obtained if one wants to use a metallization bath of a temperature from the (333÷353) K range in order to obtain the required resistor parameters.","PeriodicalId":329807,"journal":{"name":"2017 21st European Microelectronics and Packaging Conference (EMPC) & Exhibition","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124264122","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":"Liquid Solid Diffusion (LSD) bonding: A novel joining technology","authors":"A. Larsson, T. A. Tollefsen, K. Aasmundtveit, O. M. L⊘vvik","doi":"10.23919/EMPC.2017.8346886","DOIUrl":"https://doi.org/10.23919/EMPC.2017.8346886","url":null,"abstract":"Liquid Solid Diffusion (LSD) bonding is a novel joining technology forming solid and liquid two-phase field joints from simple binary systems. LSD creates joints that are applicable at temperatures above the melting temperature of the material composition of the initial bond. Liquid and solid inter-diffusion transform the joint composition and microstructure. The final joint is characterized by incongruent re-melting forming a coherent continuous porous solid solution phase with liquefied pores. This article briefly describes the methodology and presents experimental results based on the Au-Ge system. High quality joints were created. The effective melting point was increased by more than 200 °C above the initial eutectic melting point of the system.","PeriodicalId":329807,"journal":{"name":"2017 21st European Microelectronics and Packaging Conference (EMPC) & Exhibition","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123818512","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":"Embedded mini heat pipes as thermal solution for PCBs","authors":"J. S. de Sousa, M. Unger, P. Fulmek, P. Haumer, J. Nicolics","doi":"10.23919/EMPC.2017.8346829","DOIUrl":"https://doi.org/10.23919/EMPC.2017.8346829","url":null,"abstract":"Rapidly ongoing miniaturization in combination with increasing electronic functionality — particularly in high end applications — leads to the need of progresses in the PCB cooling technology. Improved thermal performance of PCBs should allow, at lowest possible cost, to remove the power loss from components without exceeding the specified maximum temperature. Heat decentralization, i.e., heat spreading and heat guiding in the PCB is one opportunity to achieve high cooling effectiveness from passive systems. In order to provide an effective heat transport from the heat source into the lateral direction of the PCB, embedded miniaturized heat pipes are a promising solution for the heat spreading problem. Heat pipes have an extremely high effective thermal conductivity compared to solids because they are based on a different heat transfer mechanism. Heat pipes are basically a closed vessel (usually a copper pipe) whereas fluid and gas (often water and air) are trapped inside at low pressures. Inner structures called wick are made in such way to provide means for fluid water flow inside the vessel. When heat is applied on the evaporator section of the heat pipe, the fluid inside is vaporized and flows to the other end of the heat pipe (condenser) due to the difference in pressure. At the condenser section the heat flow is absorbed, so that the vapor condenses into a so called wick structure. Capillary forces acting inside the porous wick structure drives the liquid back to the evaporator. However, since this process is governed by vaporization and condensation of the medium inside the heat pipe along a certain distance, the heat transport capacity is limited related to the geometrical dimensions. Within the scope of this work, the heat transfer performance of miniaturized heat pipes (diameters 1.5 mm and 2.0 mm) is quantified by thermal 3D simulations. The heat spreading capability of miniaturized heat pipes embedded in four different test PCBs are investigated. The effective thermal conductivity and the thermal resistances between the location of the temperature maximum and a defined point of the heat pipe at ambient temperature are determined in dependence on different design parameters, respectively. One important parameter is the thermal interconnection between the copper structure of the PCB and the heat pipe: interconnects by copper filled slots or vias — both standard manufacturing steps in the AT&S embedding process — proved to be superior solutions. The simulation results are compared with experimental ones from a previous study and are in satisfying agreement.","PeriodicalId":329807,"journal":{"name":"2017 21st European Microelectronics and Packaging Conference (EMPC) & Exhibition","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116801222","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":"The influence of corner bonding and underfilling techniques on the reliability of 3D TMV PoP structures in SMT assembly","authors":"M. Kościelski, J. Sitek, J. Borecki, T. Serzysko","doi":"10.23919/EMPC.2017.8346915","DOIUrl":"https://doi.org/10.23919/EMPC.2017.8346915","url":null,"abstract":"The paper shows the results of investigation of quality and reliability of soldered joints in 3D TMV PoP structures after assembly using corner bonding and underfilling techniques processes. The 3D solder joints reliability studies were realized using thermal shocks (TS). The results showed that underfilling technique the most positive influences on the 3D TMV PoP structures reliability, but other technological and materials parameters have to be taken into consideration during their assembly process planning. The usage of no optimal technological parameters during the 3D TMV PoP structures assembly decreased reliability of their solder joints up to 30%.","PeriodicalId":329807,"journal":{"name":"2017 21st European Microelectronics and Packaging Conference (EMPC) & Exhibition","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115409162","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":"The mechanical strength of microvias in reflow cycling and environmental aging","authors":"J. Kiilunen, L. Frisk","doi":"10.23919/EMPC.2017.8346871","DOIUrl":"https://doi.org/10.23919/EMPC.2017.8346871","url":null,"abstract":"Microvias are an integral part of electronics miniaturization as they enable high density interconnections in printed circuit boards (PCBs). Consequently, also the importance of their reliability and quality has increased. In this paper, the mechanical strength of microvias was studied using shear testing. The main aim was to examine if shear testing could be used to analyze the quality of the microvias and their failure modes. The test was performed by applying lead-free solder paste on to test pads with microvias. A reflow process was then used to form solder bumps. Test parameters included number of performed reflow cycles, number of microvias in a test pad and used surface finish. In addition, the effect of thermal cycling and constant temperature/humidity aging on the shear test results was examined. All the failures observed in the shear test occurred within the test PCB. That is, no bulk solder or intermetallic failures were observed. Increasing the number of reflow cycles from one to five caused a more significant drop in the measured shear energy values of the microvias than in the maximum shear force values. No significant difference could be observed in the shear test results between the test pads with different number of microvias. The aging of the samples did not change the failure mode. The thermal cycling test had a more significant effect on the shear test results than the temperature/humidity test. Based on failure analysis, the samples failed within the epoxy layer between the copper pad and the glass fibers of the microvia layer. The microvias were observed to fail directly beneath the copper pads, which was caused by deliberately using an unoptimized manufacturing process. The performed shear test showed promising results as a test method for the reliability and quality testing of microvias.","PeriodicalId":329807,"journal":{"name":"2017 21st European Microelectronics and Packaging Conference (EMPC) & Exhibition","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122929327","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":"Hot bar joining method for medical applications","authors":"David Wagner, K. Pitschmann, F. Sebastian, B. Schmidt, M. Detert, U. Schumann","doi":"10.23919/EMPC.2017.8346844","DOIUrl":"https://doi.org/10.23919/EMPC.2017.8346844","url":null,"abstract":"The goal is to use the hot bar method to join the conductive lines of a flexible interposer with copper wires, which are located inside of the catheter wall. These copper wires with a diameter of 150 μm were integrated during the extrusion process of a polyethylene catheter with a diameter of 3 mm and a wall thickness of 1 mm. The wires will be used as signal and power lines. Because the copper wires located inside the catheter wall, the polyethylene material above the copper wires must be removed for joining the interposer copper lines. The material ablation was done by a femtosecond laser. Detailed knowledge about the heat sensitive handling with the polyethylene catheter must obtained before start the joining procedures. For the setup of the final joining procedure, there were used different types of test vehicles. With the help of the test vehicles the joining method is evaluated. Therefore, a hot bar stamp is placed at the back of the polyimide layer. The investigated parameters of the hot bar are stamp temperature, stamp force and time. After the setup analysis of the sensor test vehicle, the optimal joining parameters will be discovered and the flexible interposer and the copper wires inside of the catheter wall could be joined in future steps. Finally, non-destructive (ultrasound, x-ray) and destructive methods (tweezer pull test, microsection) will be investigated to evaluate the joining quality and quantity of the test vehicle and the final sensor catheter.","PeriodicalId":329807,"journal":{"name":"2017 21st European Microelectronics and Packaging Conference (EMPC) & Exhibition","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125069808","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":"Optical pressure sensors for harsh environment","authors":"J. Somer, I. Szendiuch, F. Urban","doi":"10.23919/EMPC.2017.8346868","DOIUrl":"https://doi.org/10.23919/EMPC.2017.8346868","url":null,"abstract":"This paper deals with the design, manufacturing, and evaluation of a new optical pressure sensor produced by using Low Temperature Co-fired Ceramic technology. This optical sensor is designed for the applications with harsh operating conditions. The sensor has to withstand temperatures up to 300 °C and work in chemically aggressive environment. Low Temperature Co-fired Ceramic is chosen for the sensor body to meet these operation conditions. This material is easy to process and easy to use for prototype manufacturing. Another important factor is the electromagnetic susceptibility of the sensor, which restricts the use of electronic pressure sensors in the application with high levels of electromagnetic interference. Therefore the optical sensing method was used for the sensor design. The paper gives a brief overview of the benefits and problems related to the optical measurement methods suitable for pressure sensor interrogation. Optical spectrum change based measurement method was chosen for the best sensor performance. Pressure transducer presented in this paper is based on the interrogation of the light spectra reflected from the Fabry-Pérot optical cavity. The Fabry-Pérot optical resonator is formed on the inner surface of ceramic diaphragm in the Low Temperature Co-fired Ceramic structure of the sensor body. The cavity of the resonator is between the flat end of the optical fiber and the reflective mirror layer on the diaphragm. The samples of the fiber optic sensors were calibrated by using the reference pressure gauge and the operating characteristics of the sensors are measured. The sensors were designed for various pressure ranges, samples were manufactured, measured and tested. A selected optical method for enhancing the temperature compensation and measurement accuracy is discussed. Specific interrogation unit was used for the pressure sensor measurement and evaluation.","PeriodicalId":329807,"journal":{"name":"2017 21st European Microelectronics and Packaging Conference (EMPC) & Exhibition","volume":"2016 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123782518","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":"Acceleration measurements during reactive bonding processes","authors":"Irina Spies, A. Schumacher, S. Knappmann, B. Rheingans, J. Janczak-Rusch, L. Jeurgens","doi":"10.23919/EMPC.2017.8346881","DOIUrl":"https://doi.org/10.23919/EMPC.2017.8346881","url":null,"abstract":"In this work, the dynamics of the bonding process using reactive multilayer systems (RMS) is studied by use of acceleration sensors. A piezoelectric accelerometer with a wide dynamic range was selected to measure the vertical acceleration during the reaction process using a Ni/Al RMS foil. This sensor was integrated into a die bonding tool. Then, bonding experiments were performed with dummy plates and substrates by igniting the RMS and measuring the sensor signal simultaneously. It was found that a strong sensor signal occurs at the time when the reaction of the RMS is completed. By additional cross sectional analysis of the bonding area, the correlation between signal height and total volume contraction has been investigated. The obtained results demonstrate that this experimental setup can be used to find materials and process conditions for bonding with significantly reduced shock-wave, lowering the risk of damage to the assembled device.","PeriodicalId":329807,"journal":{"name":"2017 21st European Microelectronics and Packaging Conference (EMPC) & Exhibition","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126461201","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":"Low-temperature sintering behavior of ternary solder and copper powder for high-power device packaging","authors":"Y. Eom, Keon‐Soo Jang, Jihye Son, Hyun-Cheol Bae, Kwang-Seong Choi","doi":"10.23919/EMPC.2017.8346833","DOIUrl":"https://doi.org/10.23919/EMPC.2017.8346833","url":null,"abstract":"For a high-power device of hybrid electrical vehicles requiring high thermal reliability, the concept of low temperature sintering material composed of Ag coated Cu, Sn/Ag/Cu ternary solder and chemical components removing oxide on the surface of metal fillers was studied under a processing temperature of 240oC. Due to the limited thermal reliability of conventional Tin based solder systems, the high-power device applications with a good thermal performance have been hindered because these solder materials were possibly re-melted under extreme operating conditions. Isotropic conductive paste based on thermosetting resin was previously investigated. With increase of temperature during processing, the Sn/Ag/Cu ternary solder in low temperature sintering material was melted at the melting temperature (220oC) of solder, and then, Sn was reacted with the adjacent Cu particles, producing intermetallic compound such as Cu6Sn5 or Cu3Sn. The metallic reaction between Tin and copper increased the melting temperature of the yielded metal filler from 220oC to 360oC. Therefore, we expect the enhanced reliability and thermal stability of low temperature sintering material, compared to the solder-based conventional conductive interconnection materials, because the created metal filler product (intermetallic compound) in low temperature sintering material after processing will not be re-melted at the similar operating temperature to the processing temperature, 240oC. After sintering processing of low temperature sintering material in present research, 3.7 wt.% of the residue chemicals was detected by TGA because most of chemical components was evaporated during sintering process. In conclusion, low temperature sintering material is believed to be a good candidate material for the high-power device packaging due to the phenomena of the increased melting temperature of metal filler.","PeriodicalId":329807,"journal":{"name":"2017 21st European Microelectronics and Packaging Conference (EMPC) & Exhibition","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127156356","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}