Thermal and mechanical analysis of flip-chips on a liquid cooled multichip module

Conference · Wed Jan 01 00:00:00 EST 1992

OSTI ID:6628830

Narayanan, R ^[1]; Hall, P M ^[2]; Chanchani, R ^[3]

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1. North Carolina Univ., Charlotte, NC (United States). Dept. of Mechanical Engineering
2. Johnson C. Smith Univ., Charlotte, NC (United States)
3. Sandia National Labs., Albuquerque, NM (United States)

In this paper, thermal analysis of a three dimensional quarter model of a 156 pad flip-chip on a liquid cooled multichip module with 75 other chips is simulated using COSMOS -- finite element software. Both flip-chip (pad grid array type) and TAB type of interconnections are used for the module. The total power on the board is 67 watts, the flip-chips generating up to 1.5 watts each and the one TAB type generating 12 waits. Each chip can be modeled independently due to the absence of cross-heating by its neighbors. Forced convection liquid cooling using an organic coolant with various flow rates and thus various convection coefficients is used for the study. The temperature rise in the boundary layer of the coolant was 8F[degrees] at the coolant flow rate of 0.08 gallons per minute for the flip-chip with 1.5 watts. The maximum thermal strains calculated were found to be 0.35% (if the temperature of zero strain is assumed to be 0[degrees]F, and Young's modulus of solder is 2 Mpsi). The maximum shears were found in the corner bump, and they differed from the next bump by 20%. Polyimide layers above and below the solder bumps were found to contribute about 80% of the thermal resistance These results are used in a Coffin-Manson analysis to predict adequate life (cycles) for the high lead solder bumps (95%Pb--5%Sn).

• Research Organization: Sandia National Labs., Albuquerque, NM (United States)
• Sponsoring Organization: USDOE; USDOE, Washington, DC (United States)
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 6628830
• Report Number(s): SAND-92-2554C; CONF-9306104-3; ON: DE93007609
• Resource Relation: Conference: 43. electronic component and technology conference, Orlando, FL (United States), 1-3 Jun 1993
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
INTEGRATED CIRCUITS
MECHANICAL PROPERTIES
THERMAL ANALYSIS
CREEP
ELASTICITY
FINITE ELEMENT METHOD
IMIDES
LEAD BASE ALLOYS
METALLURGICAL FLUX
MICROELECTRONICS
POLYMERS
SHEAR
SIZE
STRAINS
STRESS ANALYSIS
TIN ALLOYS
ALLOYS
CALCULATION METHODS
ELECTRONIC CIRCUITS
LEAD ALLOYS
MICROELECTRONIC CIRCUITS
NUMERICAL SOLUTION
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
TENSILE PROPERTIES
426000* - Engineering- Components
Electron Devices & Circuits- (1990-)