NDLI: Electroless Nickel/Copper Plating as a New Bump Metallization

Content Provider	IEEE Xplore Digital Library
Author	Aschenbrenner, R. Ostmann, A. Beutler, U. Simon, J. Reichl, H.
Copyright Year	1994
Description	Author affiliation: Technische Universitat, Berlin (Aschenbrenner, R.)
Abstract	An electroless bumping method was developed both for Rip-Chip and TAB applications. Electroless Ni/Cu plating is a maskless low cost approach to bumping directly on aluminum bondpads. An immersion tin layer for coating and soldering is plated on the copper. Due to the high alkalinity (pH>12) of electroless Cu baths, a thick Ni layer of about 7 P/spl mu/m is required on the aluminum for sealing. A shear strength of 180 cN and a contact resistance of less than 2 m/spl omega/ for the bumps were obtained. Because of the high hardness of nickel, conventional gang bonding techniques are not applicable. The hardness of electroless copper is about 200 mHV25 and after annealing in the range of 130-150 mHV25. Thermocompression gang bonding of Au plated tape to the Ni/Cu/Sn metallization was carded out. The average pull strength was 50 cN. Further investigations of the deposited copper are the influence of the size and electroless solder plating.
Starting Page	390
Ending Page	395
File Size	495050
Page Count	6
File Format	PDF
ISBN	0930815394
DOI	10.1109/ICMCM.1994.753580
Language	English
Publisher	Institute of Electrical and Electronics Engineers, Inc. (IEEE)
Publisher Date	1994-04-13
Access Restriction	Subscribed
Rights Holder	Institute of Electrical and Electronics Engineers, Inc. (IEEE)
Subject Keyword	Nickel Copper Metallization Bonding Aluminum Integrated circuit packaging Costs Tin Gold Kinetic theory
Content Type	Text
Resource Type	Article

Sl.	Authority	Responsibilities	Communication Details
1	Ministry of Education (GoI), Department of Higher Education	Sanctioning Authority	https://www.education.gov.in/ict-initiatives
2	Indian Institute of Technology Kharagpur	Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project	https://www.iitkgp.ac.in
3	National Digital Library of India Office, Indian Institute of Technology Kharagpur	The administrative and infrastructural headquarters of the project	Dr. B. Sutradhar bsutra@ndl.gov.in
4	Project PI / Joint PI	Principal Investigator and Joint Principal Investigators of the project	Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon
5	Website/Portal (Helpdesk)	Queries regarding NDLI and its services	support@ndl.gov.in
6	Contents and Copyright Issues	Queries related to content curation and copyright issues	content@ndl.gov.in
7	National Digital Library of India Club (NDLI Club)	Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach	clubsupport@ndl.gov.in
8	Digital Preservation Centre (DPC)	Assistance with digitizing and archiving copyright-free printed books	dpc@ndl.gov.in
9	IDR Setup or Support	Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops	idr@ndl.gov.in