A new flip-chip technology for high-density packaging

Author

Smith, Donald L. ; Alimonda, Andrew S.

Author_Institution

Xerox Palo Alto Res. Center, CA, USA

fYear

1996

fDate

28-31 May 1996

Firstpage

1069

Lastpage

1073

Abstract

We have used sputter-deposition and standard lithography to fabricate arrays of cantilevered metal micro-springs on 80 μm pitch, and we have obtained 100% electrical contact to 200-pad chips bonded face-down against them. Four-point resistance is 0.38 Ω for Mo-Cr springs on Al pads. Since the contacts themselves are not bonded and since the springs have high elastic compliance, this technology is very resistant to mechanical shock and stress, can accommodate large nonplanarity in mating surfaces, facilitates replacement of bad chips, and could be used for wafer-scale probing

Keywords

contact resistance; flip-chip devices; integrated circuit packaging; lithography; sputter deposition; 0.38 ohm; 80 micron; Al; Mo-Cr; array fabrication; cantilevered metal micro-spring; elastic compliance; electrical contact; flip-chip technology; four-point resistance; high-density packaging; lithography; mechanical shock; nonplanarity; sputter deposition; stress; wafer-scale probing; Contacts; Dielectric substrates; Electric shock; Fingers; Lithography; Packaging; Springs; Sputtering; Tensile stress; Wafer bonding;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronic Components and Technology Conference, 1996. Proceedings., 46th

Conference_Location

Orlando, FL

ISSN

0569-5503

Print_ISBN

0-7803-3286-5

Type

conf

DOI

10.1109/ECTC.1996.550814

Filename

550814