Thermomigration technology for silicon ball grid array package fabrication

Vatery I. Rudakov; Boris V. Mochalov; Nikolai I. Plis

doi:10.1117/12.683487

10 June 2006 Thermomigration technology for silicon ball grid array package fabrication

Vatery I. Rudakov, Boris V. Mochalov, Nikolai I. Plis

Proceedings Volume 6260, Micro- and Nanoelectronics 2005; 62601D (2006) https://doi.org/10.1117/12.683487
Event: Micro- and Nanoelectronics 2005, 2005, Zvenigorod, Russian Federation

Abstract

Single-crystal silicon is an ideal material for packages. Moreover, it has the same temperature coefficient of expansion as a chip. Silicon has high thermal conductivity and low dielectric penetrability. It also has excellent mechanical properties. In addition, recent trends in engineering literature indicate a growing interest in the use of silicon as a mechanical material. We have developed a design and fabrication technology of SBGA packages. The SBGA package consists of silicon substrate with ball leads arranged under the package base in several rows. A main problem with such a package is a formation of feedthroughs in the silicon substrate. The feedthroughs can be fabricated by means of the aluminum thermomigration (temperature gradient zone melting) method. The thermomigration process is due to dissolution of silicon atoms on the hot side of the molten zone, the transport of the atoms across the zone, and their deposition on the cold side of the zone. We fabricated SBGA carrier which has 0.2×0.2 mm sizes of the feedthroughs and 1.27 mm pitch footprint. The SBGA package has peripheral ball array. Package sizes have 25×25 mm and 576 ball leads. A resistance 0.4 mm length of the feedthrough is equal to 0.5 Ω. The parasitic capacitance is also quite small. In the case 1000 Ω-cm silicon, a parasitic capacitance is only 2.0 pF. Taking this values of 0.5 Ω and 2.0 pF, then we see that the RC time constant of a typical feedthrough is on the order of 1.0 ps.

Citation Download Citation

Vatery I. Rudakov, Boris V. Mochalov, and Nikolai I. Plis "Thermomigration technology for silicon ball grid array package fabrication", Proc. SPIE 6260, Micro- and Nanoelectronics 2005, 62601D (10 June 2006); https://doi.org/10.1117/12.683487

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available