Pub Date : 1988-05-11DOI: 10.1109/ITHERM.1988.28701
J. Emerson
Difficulties resulting from plastic encapsulation for large semiconductor chips, electronic modules such as ceramic hybrid circuits, and passive components are classified into three problem areas. These are temperature excursion, moisture, and electrical. The failure related to each item is listed. A review of thermally reduced failures of encapsulated devices, and assembly sequences and testing are discussed for a broad range of applications.<>
{"title":"Thermal phenomena during the encapsulation of electronic devices","authors":"J. Emerson","doi":"10.1109/ITHERM.1988.28701","DOIUrl":"https://doi.org/10.1109/ITHERM.1988.28701","url":null,"abstract":"Difficulties resulting from plastic encapsulation for large semiconductor chips, electronic modules such as ceramic hybrid circuits, and passive components are classified into three problem areas. These are temperature excursion, moisture, and electrical. The failure related to each item is listed. A review of thermally reduced failures of encapsulated devices, and assembly sequences and testing are discussed for a broad range of applications.<<ETX>>","PeriodicalId":226424,"journal":{"name":"InterSociety Conference on Thermal Phenomena in the Fabrication and Operation of Electronic Components. I-THERM '88","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128503074","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}
Pub Date : 1988-05-11DOI: 10.1109/ITHERM.1988.28678
T. Sullivan, J. Rosenberg, S. Matsuoka
A photoelastic analysis is used to determine stress distributions within an epoxy encapsulation material for idealized geometries. Experimental results are compared with analytical and numerical predictions based on actual material data. It is demonstrated that to determine quantitative stress levels using photoelasticity it is necessary to separate orientation effects from an elastically active portion of stress. These 'elastic' stress levels are predicted using linear elastic finite-element models, and agreement with experimental data is obtained when appropriate input parameters are chosen.<>
{"title":"Photoelastic and numerical investigation of thermally-induced restrained shrinkage stresses in plastics","authors":"T. Sullivan, J. Rosenberg, S. Matsuoka","doi":"10.1109/ITHERM.1988.28678","DOIUrl":"https://doi.org/10.1109/ITHERM.1988.28678","url":null,"abstract":"A photoelastic analysis is used to determine stress distributions within an epoxy encapsulation material for idealized geometries. Experimental results are compared with analytical and numerical predictions based on actual material data. It is demonstrated that to determine quantitative stress levels using photoelasticity it is necessary to separate orientation effects from an elastically active portion of stress. These 'elastic' stress levels are predicted using linear elastic finite-element models, and agreement with experimental data is obtained when appropriate input parameters are chosen.<<ETX>>","PeriodicalId":226424,"journal":{"name":"InterSociety Conference on Thermal Phenomena in the Fabrication and Operation of Electronic Components. I-THERM '88","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116911345","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}
Pub Date : 1988-05-11DOI: 10.1109/ITHERM.1988.28703
A. S. Jordan, R. Caruso
Summary form only given. Large temperature gradients and substantial differences in thermal expansion coefficients are among the major factors for thermal stress generation in many materials systems. The field of electronic materials provides striking illustrations with regard to the role of thermal stress in crystal growth. In the LEC (liquid encapsulation Czochralski) growth of GaAs and InP, the current understanding of dislocation generation is based on the quasi-steady state (QSS) heat transfer/thermal stress model. The theory not only yields correctly the observed dislocation patterns of
{"title":"Thermal stresses in the bulk and epitaxial growth of III-V materials","authors":"A. S. Jordan, R. Caruso","doi":"10.1109/ITHERM.1988.28703","DOIUrl":"https://doi.org/10.1109/ITHERM.1988.28703","url":null,"abstract":"Summary form only given. Large temperature gradients and substantial differences in thermal expansion coefficients are among the major factors for thermal stress generation in many materials systems. The field of electronic materials provides striking illustrations with regard to the role of thermal stress in crystal growth. In the LEC (liquid encapsulation Czochralski) growth of GaAs and InP, the current understanding of dislocation generation is based on the quasi-steady state (QSS) heat transfer/thermal stress model. The theory not only yields correctly the observed dislocation patterns of","PeriodicalId":226424,"journal":{"name":"InterSociety Conference on Thermal Phenomena in the Fabrication and Operation of Electronic Components. I-THERM '88","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127708745","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}
Pub Date : 1988-05-11DOI: 10.1109/ITHERM.1988.28691
T. Crowley, R. Tuzla, L. Wenzel, J.C. Chen
Convective nucleate boiling heat transfer from a plane vertical surface to nitrogen in two-phase flow is discussed. A 6.3-mm diameter heat source was used to represent a single semiconductor chip or chip carrier. Experiments were performed to study the parametric effects of vapor quality and flow rate on the heat transfer coefficient.<>
{"title":"Convective boiling of nitrogen on a short vertical surface","authors":"T. Crowley, R. Tuzla, L. Wenzel, J.C. Chen","doi":"10.1109/ITHERM.1988.28691","DOIUrl":"https://doi.org/10.1109/ITHERM.1988.28691","url":null,"abstract":"Convective nucleate boiling heat transfer from a plane vertical surface to nitrogen in two-phase flow is discussed. A 6.3-mm diameter heat source was used to represent a single semiconductor chip or chip carrier. Experiments were performed to study the parametric effects of vapor quality and flow rate on the heat transfer coefficient.<<ETX>>","PeriodicalId":226424,"journal":{"name":"InterSociety Conference on Thermal Phenomena in the Fabrication and Operation of Electronic Components. I-THERM '88","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127736246","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}
Pub Date : 1988-05-11DOI: 10.1109/ITHERM.1988.28669
T. Lestina, D. Kaminski, E. Rodriguez
An approach is developed to determine the nonuniform temperature profile on a semiconductor power diode. The temperature distribution over the large junction area of power semiconductor devices is often nonuniform due to voids or cracks in the mountdown media. Since the device packaging typically prevents direct measurement of the junction temperature, the presented technique requires the measurement of voltages and currents only. No information regarding the size or type of the void is required, and heat transfer equations are not solved. Instead, the temperature distribution is calculated using current-voltage-temperature relationships similar in form to the Shockley equation. Using these relationships, the temperature across the junction are calculated as a best fit to the voltage and current measurements. This inverse method is tested using a power diode 18 mm in diameter and rated at 100 A. Preliminary measurements indicate that the method calculates peak junction temperature as accurately as existing techniques.<>
{"title":"An inverse method to determine the temperature profile on a semiconductor power diode","authors":"T. Lestina, D. Kaminski, E. Rodriguez","doi":"10.1109/ITHERM.1988.28669","DOIUrl":"https://doi.org/10.1109/ITHERM.1988.28669","url":null,"abstract":"An approach is developed to determine the nonuniform temperature profile on a semiconductor power diode. The temperature distribution over the large junction area of power semiconductor devices is often nonuniform due to voids or cracks in the mountdown media. Since the device packaging typically prevents direct measurement of the junction temperature, the presented technique requires the measurement of voltages and currents only. No information regarding the size or type of the void is required, and heat transfer equations are not solved. Instead, the temperature distribution is calculated using current-voltage-temperature relationships similar in form to the Shockley equation. Using these relationships, the temperature across the junction are calculated as a best fit to the voltage and current measurements. This inverse method is tested using a power diode 18 mm in diameter and rated at 100 A. Preliminary measurements indicate that the method calculates peak junction temperature as accurately as existing techniques.<<ETX>>","PeriodicalId":226424,"journal":{"name":"InterSociety Conference on Thermal Phenomena in the Fabrication and Operation of Electronic Components. I-THERM '88","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133440050","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}
Pub Date : 1988-05-11DOI: 10.1109/ITHERM.1988.28692
M. Charmchi
The general aspects of the thermal characteristics of the dot-matrix impact print heads are discussed. To address the problem, a brief analysis for a typical print head is presented. The rate of heat generated in a dot-matrix print head, depending on its speed, print quality, and print mode (i.e. graphic or text mode), can be very large. The sources of the heat dissipation are found to be: the resistance of the coiled wire (resistance heating) and the induced transient magnetic field (induction heating). In many situations, the encountered heat fluxes are large, hence, the use of the extended surfaces are required.<>
{"title":"Thermal characteristics of dot-matrix print heads","authors":"M. Charmchi","doi":"10.1109/ITHERM.1988.28692","DOIUrl":"https://doi.org/10.1109/ITHERM.1988.28692","url":null,"abstract":"The general aspects of the thermal characteristics of the dot-matrix impact print heads are discussed. To address the problem, a brief analysis for a typical print head is presented. The rate of heat generated in a dot-matrix print head, depending on its speed, print quality, and print mode (i.e. graphic or text mode), can be very large. The sources of the heat dissipation are found to be: the resistance of the coiled wire (resistance heating) and the induced transient magnetic field (induction heating). In many situations, the encountered heat fluxes are large, hence, the use of the extended surfaces are required.<<ETX>>","PeriodicalId":226424,"journal":{"name":"InterSociety Conference on Thermal Phenomena in the Fabrication and Operation of Electronic Components. I-THERM '88","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116782549","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}
Pub Date : 1988-05-11DOI: 10.1109/ITHERM.1988.28671
A. Tseng
A microcomputer finite-element code has been used to analyze the steady-state thermal behavior of a microstrip Gunn diode circuit with the goal of reducing the device temperature by varying microstrip thicknesses. Although the microstrip is designed mainly for electronic purposes, the analysis has shown that it can also provide a favorable thermal environment to alleviate the device temperature. A two-step modeling approach that can reduce the computer memory needed for computation was used to allow the present study to be conducted on a microcomputer. In this approach, the temperature increases in the device and in the heat sink are considered separately. The device temperature is analyzed by the microcomputer finite-element technique. The heat-sink resistance is calculated by simplified analytical schemes.<>
{"title":"A microcomputer thermal analysis of a Gunn diode in microstrip circuits","authors":"A. Tseng","doi":"10.1109/ITHERM.1988.28671","DOIUrl":"https://doi.org/10.1109/ITHERM.1988.28671","url":null,"abstract":"A microcomputer finite-element code has been used to analyze the steady-state thermal behavior of a microstrip Gunn diode circuit with the goal of reducing the device temperature by varying microstrip thicknesses. Although the microstrip is designed mainly for electronic purposes, the analysis has shown that it can also provide a favorable thermal environment to alleviate the device temperature. A two-step modeling approach that can reduce the computer memory needed for computation was used to allow the present study to be conducted on a microcomputer. In this approach, the temperature increases in the device and in the heat sink are considered separately. The device temperature is analyzed by the microcomputer finite-element technique. The heat-sink resistance is calculated by simplified analytical schemes.<<ETX>>","PeriodicalId":226424,"journal":{"name":"InterSociety Conference on Thermal Phenomena in the Fabrication and Operation of Electronic Components. I-THERM '88","volume":"233-234 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125486661","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}
Pub Date : 1988-05-11DOI: 10.1109/ITHERM.1988.28683
M. Chyu, L. Wu, J. Murthy
Summary form only given. The detailed local distribution is obtained of the convective heat transfer coefficient on the fin structure. A mass transfer system using the naphthalene sublimation technique is chosen for the study. The test model is fabricated by coating a layer of naphthalene on the fin surface; this gives the surface an equivalence to the isothermal boundary condition in heat transfer. This also implies that the fin array has 100% of fin efficiency. A state-of-the-art, computer-automated measurement system is used to acquire the naphthalene surface profiles before and after the surface exposure to the air stream in a wind tunnel. The present test uses fixed values of fin height-to-space ratio (approximately 1.5) and the streamwise dimension (approximately 5 fin heights).<>
{"title":"Forced convection heat transfer of a vertical shrouded fin array","authors":"M. Chyu, L. Wu, J. Murthy","doi":"10.1109/ITHERM.1988.28683","DOIUrl":"https://doi.org/10.1109/ITHERM.1988.28683","url":null,"abstract":"Summary form only given. The detailed local distribution is obtained of the convective heat transfer coefficient on the fin structure. A mass transfer system using the naphthalene sublimation technique is chosen for the study. The test model is fabricated by coating a layer of naphthalene on the fin surface; this gives the surface an equivalence to the isothermal boundary condition in heat transfer. This also implies that the fin array has 100% of fin efficiency. A state-of-the-art, computer-automated measurement system is used to acquire the naphthalene surface profiles before and after the surface exposure to the air stream in a wind tunnel. The present test uses fixed values of fin height-to-space ratio (approximately 1.5) and the streamwise dimension (approximately 5 fin heights).<<ETX>>","PeriodicalId":226424,"journal":{"name":"InterSociety Conference on Thermal Phenomena in the Fabrication and Operation of Electronic Components. I-THERM '88","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124024468","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}
Pub Date : 1988-05-11DOI: 10.1109/ITHERM.1988.28690
R. Krane, J. Parsons, A. Bar-Cohen
The thermal aspects are discussed of an immersion-cooled computer designed to operate at cryogenic temperatures. Several of the major thermal design issues are discussed in detail. These include: (1) the selection of a working fluid; (2) the determination of the mode, or modes, of heat transfer to be used: (3) the selection, or development, of any required heat transfer correlations; and (4) the selection of a refrigeration system. The results of a preliminary analysis of a candidate thermal control system are also presented.<>
{"title":"Design of a candidate thermal control system for a cryogenically-cooled computer","authors":"R. Krane, J. Parsons, A. Bar-Cohen","doi":"10.1109/ITHERM.1988.28690","DOIUrl":"https://doi.org/10.1109/ITHERM.1988.28690","url":null,"abstract":"The thermal aspects are discussed of an immersion-cooled computer designed to operate at cryogenic temperatures. Several of the major thermal design issues are discussed in detail. These include: (1) the selection of a working fluid; (2) the determination of the mode, or modes, of heat transfer to be used: (3) the selection, or development, of any required heat transfer correlations; and (4) the selection of a refrigeration system. The results of a preliminary analysis of a candidate thermal control system are also presented.<<ETX>>","PeriodicalId":226424,"journal":{"name":"InterSociety Conference on Thermal Phenomena in the Fabrication and Operation of Electronic Components. I-THERM '88","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117085536","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}
Pub Date : 1988-05-11DOI: 10.1109/ITHERM.1988.28684
S. Kuo, C. Tien
A heat treatment augmentation technique utilizing a foam-material system for potential application to electronics cooling is presented. The geometry under consideration is a foam-material filled duct with discrete heat sources on its walls. The volume-averaged momentum and energy equations are used to analyze the flow and heat transfer. The present analysis includes the boundary, inertial, and dispersion effects. Thermal dispersion caused by the presence of the solid matrix plays a key role in heat transfer augmentation. Numerical simulations are carried out to obtain the Nusselt number and wall temperature distributions. The results show that an increase of two to four times in heat transfer is achievable as compared to that of laminar slug-flow in a clear duct.<>
{"title":"Heat transfer augmentation in a foam-material filled duct with discrete heat sources","authors":"S. Kuo, C. Tien","doi":"10.1109/ITHERM.1988.28684","DOIUrl":"https://doi.org/10.1109/ITHERM.1988.28684","url":null,"abstract":"A heat treatment augmentation technique utilizing a foam-material system for potential application to electronics cooling is presented. The geometry under consideration is a foam-material filled duct with discrete heat sources on its walls. The volume-averaged momentum and energy equations are used to analyze the flow and heat transfer. The present analysis includes the boundary, inertial, and dispersion effects. Thermal dispersion caused by the presence of the solid matrix plays a key role in heat transfer augmentation. Numerical simulations are carried out to obtain the Nusselt number and wall temperature distributions. The results show that an increase of two to four times in heat transfer is achievable as compared to that of laminar slug-flow in a clear duct.<<ETX>>","PeriodicalId":226424,"journal":{"name":"InterSociety Conference on Thermal Phenomena in the Fabrication and Operation of Electronic Components. I-THERM '88","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1988-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116996198","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}
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