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High-performance power package for power-integrated circuit devices
World Abstracts on Microelectronics and Reliability Quantification of thermal contact conductance in electronic packages. WILLIAMS. CH1LDRES and G. P. PETERSON. IEEE Trans. Compon. Hybrids mfg Technol. 12(4), 717 (1989). Recent investigations involving the thermal contact resistance at the interfaces between different types of materials used in the construction of electronic packages have made it possible to quantify, as a function of the change in chip temperature, the interface resistances occurring within electronic packages. The results are presented of an investigation in which a numerical technique was used to predict the interface pressures. Combining these predicted pressures and the results of previous investigations, the individual thermal contact resistances and overall package resistance were determined for an 18-lead plastic dual-in-line package constructed from typical commercially available materials. The results indicate that the summation of the contact resistances may make up as much as 43 percent of the total package thermal resistance for the packages investigated. High-performance power package for power-integrated circuit devices. YEHYA M. KASEM and LEO G. FEINSTE1N. IEEE Trans. Compon. Hybrids mfg TechnoL 12(4), 521 (1989). A new, high-performance version of a Plastic Dual-InLine Package with improved reliability levels has been developed for high-power integrated circuit industrial and automative applications. Superior thermal capability and reliablity performances have been achieved with no increase in manufacturing cost or change in package outline. The development of this package is based on a package optimization approach. Development methodology and package characterization results will be outlined. Data for production lots of the package show a thermal performance improvement of up to 35 percent compared with currently available packages, without the aid of an external heat sink. Furthermore, qualification test results indicate that this new package has an excellent reliability performance and its long-term survival exceeds the industry standard requirements. An improvement by a factor of 4 in the resistance to device metal deformation and a factor of 7 in wirebond thermal fatigue has been achieved as a result of reducing the shear and normal stresses inside the package by proper selection of a state-of-the-art low-modulus molding compound and optimizing the leadframe design. In addition, new design fundamentals will be briefly discussed. Comparative thermal performances of various substrate materials in a simple packaging application: actual versus predicted. R. H. JENSEN, G. A. ANDREJACK, D. P. BUTTON and B. A. BYDEL. IEEE Trans. Compon. Hybrids mfg TechnoL 12(4), 537 (1989). In a previous publication, a finite element study was presented on the thermal performance of several stubstrate materials in a simple package application. Materials examined were aluminum nitride, alumina, epoxyglass, refractory-glass, and a composite consisting of alumina fibers in a polyimide matrix. Three cooling approaches were addressed: natural convection, forced convection, and a heat sink placed on the substrate face opposite the chip. In this recent work, experiments to confirm these model predictions are described. Actual packages were prepared, closely resembling those addressed in the previous model study. "Thermal test Chips" were used to make the measurements. These chips are designed for this purpose, containing both resistive heating elements and temperaturesensing elements. The test packages of each material were successively placed in natural convection, forced convection, and heat sink environments, and their respective performances were monitored. The results closely support the conclusions of the earlier model study, although numeric differences are noted.
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On locating part bins in a constrained layout area for an automated assembly process. NAZARA. YOUNIS and TOM M. CAVALIER. Comput. ind. Engng 18(2), I 11 (1990). This paper presents a zero-one mixed integer programming formulation for the optimal layout/location of a robotic assembly cell. n different rectangular part bins of fixed sizes are to be optimally located within a constrained area. The objective is to minimize a total weighted round trip travel of the robotic arm between the bins and n fixed assembly locations. The problem is solved using a standard branch and bound code as well as a Lagrangian relaxation formulation which reduces the problem to that of solving two linear programming sub-problems. Mnitichip assembly with flipped integrated circuits. K. GAIL HEINEN, WALTER H. SCHROEN, DARVlN R. EDWARDS, ARTHUR i . WILSON, ROGER J. STIERMAN and MICHAELA. LAMSON.IEEE Trans, Compon. Hybrids mfg Technol. 12(4), 650 (1989). A multichip module process has been developed using flipped-chip interconnections. The process employs plated copper bumps for superior thermal transport characteristics, active silicon as a substrate material for matched expansion properties, on-chip interconnection metallization that allows bumps to be placed over the active circuitry, and use of conventional wafer fabrication facilities for low-cost production. Details of the fabrication process will be described and a case example given. 0~, characterization of chip packages---justification, limitatious, and future. AVRAM BAR-COHEN, TOy ELPERIN and RAMI ELIASI. IEEE Trans. Compon. Hybrids mfg Technol. 12(4), 724 (1989). Recent years have witnessed a proliferation in the use of 0~ for the thermal characterization of chip packages. The longevity of 0~ can be traced to its simplicity, its utility as a figure of merit, and its convenient use in numerical analysis of packaging configurations. To enhance the utility of this parameter, it is proposed to recognize the distinct contribution of various segments of the "case" area to the junction temperature and to embody this dependence in a modified-0jc relation. The analytical basis and methodology to be used in obtaining this relation are presented and illustrated by use of detailed chip package temperatures obtained from numerical analysis of a generic PLCC package. A critical evaluation of RGA testing. R. F. S. DAVID, A. ANDREW SHORES and M. FRIEDLANDER. IEEE Trans. Compon. Hybrids mfg Technol. 12(4), 578 (1989). Silanized glass ampoules containing 12 accurately known gas mixtures were carefully prepared by a laboratory. Ampoules were sent as blind samples to four laboratories for residual gas analysis using mass spectrometry. Results showed gross inaccuracies and inconsistencies, particularly for water vapor. The deletion of this test from MIL-STD-883 is recommended. Does ultrasonic cleaning damage components? B. P. RICHARDS, P. BURTONand P. K. FOOTNER. Electron. Prod. 15 (March 1990). Concerned about the possible detrimental effect of ultrasonic cleaning on components? This report by B. P. Richards, P. Burton and P. K. Footner of GEC's Hirst Research Centre summarises the first unambiguous data to be obtained on this important topic. Volatile species from conductive die attach adhesives. RICHARD C. BENSON, TERRY E. PHILLIPS and NEWMAN DE HAAS. IEEE Trans. Compon. Hybrids mfg Technol. 12(4), 571 (1989). Microelectronic conductive die attach adhesives have been investigated to determine the volatile species that evolve during cure and after post-cure processing, such as pre-seal bakeout and burn-in. Gas chromatography/mass spectrometry was used to measure the volatile species and complementary thermal analysis measurements were also obtained.
1205
On locating part bins in a constrained layout area for an automated assembly process. NAZARA. YOUNIS and TOM M. CAVALIER. Comput. ind. Engng 18(2), I 11 (1990). This paper presents a zero-one mixed integer programming formulation for the optimal layout/location of a robotic assembly cell. n different rectangular part bins of fixed sizes are to be optimally located within a constrained area. The objective is to minimize a total weighted round trip travel of the robotic arm between the bins and n fixed assembly locations. The problem is solved using a standard branch and bound code as well as a Lagrangian relaxation formulation which reduces the problem to that of solving two linear programming sub-problems. Mnitichip assembly with flipped integrated circuits. K. GAIL HEINEN, WALTER H. SCHROEN, DARVlN R. EDWARDS, ARTHUR i . WILSON, ROGER J. STIERMAN and MICHAELA. LAMSON.IEEE Trans, Compon. Hybrids mfg Technol. 12(4), 650 (1989). A multichip module process has been developed using flipped-chip interconnections. The process employs plated copper bumps for superior thermal transport characteristics, active silicon as a substrate material for matched expansion properties, on-chip interconnection metallization that allows bumps to be placed over the active circuitry, and use of conventional wafer fabrication facilities for low-cost production. Details of the fabrication process will be described and a case example given. 0~, characterization of chip packages---justification, limitatious, and future. AVRAM BAR-COHEN, TOy ELPERIN and RAMI ELIASI. IEEE Trans. Compon. Hybrids mfg Technol. 12(4), 724 (1989). Recent years have witnessed a proliferation in the use of 0~ for the thermal characterization of chip packages. The longevity of 0~ can be traced to its simplicity, its utility as a figure of merit, and its convenient use in numerical analysis of packaging configurations. To enhance the utility of this parameter, it is proposed to recognize the distinct contribution of various segments of the "case" area to the junction temperature and to embody this dependence in a modified-0jc relation. The analytical basis and methodology to be used in obtaining this relation are presented and illustrated by use of detailed chip package temperatures obtained from numerical analysis of a generic PLCC package. A critical evaluation of RGA testing. R. F. S. DAVID, A. ANDREW SHORES and M. FRIEDLANDER. IEEE Trans. Compon. Hybrids mfg Technol. 12(4), 578 (1989). Silanized glass ampoules containing 12 accurately known gas mixtures were carefully prepared by a laboratory. Ampoules were sent as blind samples to four laboratories for residual gas analysis using mass spectrometry. Results showed gross inaccuracies and inconsistencies, particularly for water vapor. The deletion of this test from MIL-STD-883 is recommended. Does ultrasonic cleaning damage components? B. P. RICHARDS, P. BURTONand P. K. FOOTNER. Electron. Prod. 15 (March 1990). Concerned about the possible detrimental effect of ultrasonic cleaning on components? This report by B. P. Richards, P. Burton and P. K. Footner of GEC's Hirst Research Centre summarises the first unambiguous data to be obtained on this important topic. Volatile species from conductive die attach adhesives. RICHARD C. BENSON, TERRY E. PHILLIPS and NEWMAN DE HAAS. IEEE Trans. Compon. Hybrids mfg Technol. 12(4), 571 (1989). Microelectronic conductive die attach adhesives have been investigated to determine the volatile species that evolve during cure and after post-cure processing, such as pre-seal bakeout and burn-in. Gas chromatography/mass spectrometry was used to measure the volatile species and complementary thermal analysis measurements were also obtained.