Y. Hiruta et al., AN 820 PIN PGA FOR ULTRALARGE-SCALE BICMOS DEVICES, IEEE transactions on components, hybrids, and manufacturing technology, 16(8), 1993, pp. 893-901
A high pin count and high performance PGA has been developed for next-
generation ASIC devices which apply half-micron BiCMOS technology and
have a maximum usable gate count of 300k. This new package has been de
signed with due consideration of all package functions, electrical, th
ermal, and mechanical. A surface mount type pin joint was adopted to r
ealize a high wiring density of the printed wiring board. This package
has 820 pins with a 50 mil pitch, and 5 rows. A highly accurate tape
automated bonding (TAB) technology was applied to the die assembly to
achieve the narrow pitch and high pad count of the bonding between the
die and the package. The thermal resistance from the die to the ambie
nt is lower than. 1.5-degrees-C/W at 1 m/s air flow velocity. The elec
trical parameters of the package were quantified. The measured cutoff
frequency (-3 dB) was kept at 1.25 Ghz including the TAB lead. The ele
ctrical characteristics of the package have realized a complete transm
itted signal form above 50 MHz. The high reliability of the package an
d surface mount type soldering has been confirmed from temperature-cyc
ling tests and fatigue life estimation.