Artifact Details


Blech patent notebook (#406)

Catalog Number





Reports on failure analysis of gold ball wire bonds to aluminum metal contact pads, including testing after exposure up to 450 degrees C. Photomicrographs at 200x to 1000x magnification show cross section images of failure at the interface. Experimental results of changes in conductivity with time and temperature. Probable source of data for TR238 (below). Proposals for “leadless” assembly techniques including flip-chip structures.

This is 1 of 2 books issued to Blech. The other book is Blech (407).




Blech, Ilan Asriel

Biographical Notes

Illan A. Blech was born in Austria in 1936. He received a Ph.D. from Technicon-Israel Institute of Technology. He joined Fairchild in 1964 where he was a pioneer in understanding the mechanism of electromigration related to aluminum interconnects. With Gordon Moore he travelled to IBM to consult on electromigration issues with SLT modules for the IBM 360 project. A 1966 organization chart shows him as a Member of Technical Staff reporting to Harry Sello, manager of the Materials and Processes Dept. In 1968 he was manager of the Contact Technology Section. In the mid-1970s he was publishing papers from Bell Labs and from the Department of Electrical Engineering at Technicon. Blech was president of Flexus, Inc., Sunnyvale and is named as inventor patents assigned to Flexus, Tencor, Zoran, and Silicon Light Machines. Blech was the only professional colleague who agreed with Dan Shechtman’s discovery of quasicrystals at Technicon. In 1984 he deciphered Shechtman's experimental findings and offered an explanation, known as the Icosahedral Glass Model. Shechtman was awarded to Nobel Prize in Chemistry for this work in 2011.


Fairchild Semiconductor

Identifying Numbers

Document number 406


Approximately 42 dated entries over 44 pages.


12 x 10 inches



Collection Title

Fairchild Semiconductor notebooks and technical papers


The author contributed to the following R&D Technical Reports (TR) and conference papers during his service at Fairchild:

TR215 X-Ray extinction contrast topography of silicon strained by thin surface films (1965-06-14).

TR238 Some new aspects of gold-aluminum bonds (1966-04-25).

TR274 The failure of thin aluminum current carrying strips on oxidized silicon (1967-01-08).

TR277 Enhanced X-Ray diffraction from substrate crystals containing discontinuous surface films (1966-12-09).

TR294 Stacking fault contrast in X-Ray topographs of annealed si web dendrite (1967-03-22).

TR355 Electromigration in thin Al films (1968-08-19).

TR432 Electromigration in integrated circuits (1969-10-03).

Blech, I. A., Campbell, J. F., and Shepherd, W. H. Discontinuities in evaporated aluminum interconnections. 8th Annual Reliability Physics Symposium, (1970): 144-157.

Blech, I. A. and Meieran, E. S., Direct transmission electron microscope observation of electrotransport in aluminum thin films. Sixth Annual Reliability Physics Symposium, (1967): 147.

Blech, I. A. and Meieran, E. S., Erratum: electromigration in thin Al films. Journal of Applied Physics, vol. 43, iss. 2 (1972): 762.


Gift of Texas Instruments Incorporated

Lot Number