DocumentCode :
1067973
Title :
Design tradeoffs between organic polymer-on-metal PWBs and ceramic thick-film PWBs for high-density operation using leadless ceramic chip carriers
Author :
Gray, Foster L. ; Petrovich, Thomas D. ; Pylant, John K. ; Prokop, Jon S.
Author_Institution :
Texas Instrum., Austin, TX, USA
Volume :
11
Issue :
3
fYear :
1988
Firstpage :
298
Lastpage :
313
Abstract :
The physical characteristics of a standard 1750A computer card are described. The card has the following parameters: 50- Omega to 100- Omega impedance, card size of 6.58*5.88 in., cards on 0.5-in. centers, and target module weight of 1 lb. The construction chosen for each design is described. Linewidths and spaces that describe a standard design are selected. The impedance is calculated for each design and compared to the desired values. A thermomechanical analysis of the composite structure is shown to achieve a composite module coefficient of thermal expansion to 8.0 to 8.5 p.p.m./ degrees C. A thermal analysis to achieve maximum device junction temperatures of 105 degrees C is described. The resulting polymer-on-metal and ceramic-on-metal interconnect structures are compared, based on resulting card thickness, achievable card-to-card centers, substrate weight and volume, and total card weight.<>
Keywords :
packaging; printed circuit design; thermal analysis; 105 degC; 50 to 100 ohm; card size; ceramic thick-film PWBs; composite module coefficient; high-density operation; leadless ceramic chip carriers; module weight; organic polymer-on-metal PWBs; standard design; substrate weight; thermal analysis; thermomechanical analysis; Ceramics; Impedance; Instruments; Packaging; Polymers; Substrates; Surface-mount technology; Thermal expansion; Thick film circuits; Thick films;
fLanguage :
English
Journal_Title :
Components, Hybrids, and Manufacturing Technology, IEEE Transactions on
Publisher :
ieee
ISSN :
0148-6411
Type :
jour
DOI :
10.1109/33.16657
Filename :
16657
Link To Document :
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