Prediction of Thermal Performance of Wire-Bonded Plastic Ball Grid Array Package for Underhood Automotive Applications
Author:
Ramakrishna K.1, Trent J. R.2
Affiliation:
1. CMOS Platform Device Development, Digital DNA™ Laboratories, Semiconductor Products Sector, Motorola, Inc., 3501 Ed Bluestein Boulevard, Austin, TX 78721, USA 2. Transportation Products Systems Group, Semiconductor Products Sector, Motorola, Inc., 6501 William Cannon Drive West, Austin, TX 78735-8598, USA
Abstract
Thermal performance of a three chip, overmolded wire-bonded plastic ball grid array (WB-PBGA) package with four layer substrate attached to a 1.52-mm-thick, four-layer (2s2p), FR4 printed wiring board (PWB) has been evaluated under horizontal natural convection conditions for underhood automotive applications as a function of ambient temperature, package design parameters, and thermophysical properties of the package and PWB materials. A two-tier modeling approach, which accurately accounts for multidimensional heat transfer effects caused by substrate features such as vias and C5 solder joints, has been developed and implemented. In this methodology, the effect of small features is first characterized using a detailed micromodel from which an effective thermal conductivity is computed. The effective thermal conductivity is implemented in the global model thereby excluding the small features in the global model. The actual stackups of the package and PWB have been used in the computations to accurately determine the in-plane heat spreading. Using this methodology for automotive underhood applications, a parametric study of thermal performance of the WB-PBGA package has been carried out. This study shows that: 1. The maximum junction temperature rise above ambient, ΔT, decreases with increase in ambient temperature by 30% as the ambient temperature increases from 23 to 125°C. 2. ΔT decreases by 20% as the emissivity of the molding compound and the PWB surfaces increases from 0 (no radiative loss) to 0.8 under natural convection conditions. 3. The decrease in ΔT is small (∼7%) as the thermal conductivity of the die attach material varies over a wide range. 4. ΔT decreases by 30% as the thermal conductivity of the molding compound is varied over a wide range. 5. ΔT decreases by 45% as the thermal conductivity of the substrate increases (i.e., as the number of vias in the substrate increase) from no vias case to densely populated vias.
Publisher
ASME International
Subject
Electrical and Electronic Engineering,Computer Science Applications,Mechanics of Materials,Electronic, Optical and Magnetic Materials
Reference27 articles.
1. Bar-Cohen, A.
, 1987, “Thermal Management of Air- and Liquid-Cooled Multichip Modules,” IEEE Trans. Compon., Hybrids, Manuf. Technol., CHMT-10, pp. 159–175. 2. Bar-Cohen, A.
, 1988, “An Addendum and Correction to “Thermal Management of Air- and Liquid-Cooled Multichip Modules,” IEEE Trans. Compon., Hybrids, Manuf. Technol., CHMT-11, pp. 333–334. 3. Rosten, H. I., and Viswanath, R., 1994, “Thermal Modelling of the Pentium Processor Package,” Proc. of the 44th Electronic Components and Technology Conf., organized by IEEE CPMT Soc., Washington, D.C., pp. 421–428. 4. Argento, C. W., and Kromann, G. B., 1995, “The Development of Three-Dimensional Computational-Fluid Dynamics Models of PBGA Interconnect Technology for Moderate Air-Cooled Systems,” Proc. of the ITAB-95, The Intl. Symposium on Flip Chip, TAB & Ball Grid Array Technology, San Jose, CA, pp. 218–224. 5. Kromann, G. B., 1996, “Thermal Management of a C4/Ceramic-Ball-Grid-Array: The Motorola Power PC 603™ and PowerPC 604™ RISC Microprocessors,” Proc. of the Twelfth Annual SEMI-THERM–Semiconductor Thermal Measurement and Management Symp., organized by IEEE CHMT Soc., pp. 36–42.
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