Method and apparatus for jetting, manufacturing and attaching uniform solder balls
Abstract
An apparatus and process for jetting molten solder in the form of balls directly onto all the metallized interconnects lands for a ball grid array package in one step with no solder paste required. Molten solder is jetted out of a grid of holes using a piston attached to a piezoelectric crystal. When voltage is applied to the crystal it expands forcing the piston to extrude a desired volume of solder through holes in the aperture plate. When the voltage is decreased the piston reverses motion creating an instability in the molten solder at the aperture plate surface and thereby forming spherical solder balls that fall onto a metallized substrate. The molten solder balls land on the substrate and form a metallurgical bond with the metallized lands. The size of the solder balls is determined by a combination of the size of the holes in the aperture plate, the duration of the piston pulse, and the displacement of the piston. The layout of the balls is dictated by the location of the hooks in the grid. Changes in ball size and layout can be easily accomplished by changing the grid plate. This invention also allows simple preparation of uniform ballsmore »
- Inventors:
-
- Cedar Crest, NM
- Albuquerque, NM
- Issue Date:
- Research Org.:
- AT&T
- OSTI Identifier:
- 872069
- Patent Number(s):
- 5855323
- Assignee:
- Sandia Corporation (Albuquerque, NM)
- Patent Classifications (CPCs):
-
B - PERFORMING OPERATIONS B05 - SPRAYING OR ATOMISING IN GENERAL B05B - SPRAYING APPARATUS
B - PERFORMING OPERATIONS B23 - MACHINE TOOLS B23K - SOLDERING OR UNSOLDERING
- DOE Contract Number:
- AC04-76DP00789
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- method; apparatus; jetting; manufacturing; attaching; uniform; solder; balls; process; molten; form; directly; metallized; interconnects; lands; ball; grid; array; package; step; paste; required; jetted; holes; piston; attached; piezoelectric; crystal; voltage; applied; expands; forcing; extrude; desired; volume; aperture; plate; decreased; reverses; motion; creating; instability; surface; forming; spherical; fall; substrate; land; metallurgical; bond; size; determined; combination; duration; pulse; displacement; layout; dictated; location; hooks; changes; easily; accomplished; changing; allows; simple; preparation; subsequent; supply; bga; users; aperture plate; molten solder; piezoelectric crystal; piston attached; plate surface; grid array; metallurgical bond; ball grid; /239/219/222/
Citation Formats
Yost, Frederick G, Frear, Darrel R, and Schmale, David T. Method and apparatus for jetting, manufacturing and attaching uniform solder balls. United States: N. p., 1999.
Web.
Yost, Frederick G, Frear, Darrel R, & Schmale, David T. Method and apparatus for jetting, manufacturing and attaching uniform solder balls. United States.
Yost, Frederick G, Frear, Darrel R, and Schmale, David T. Fri .
"Method and apparatus for jetting, manufacturing and attaching uniform solder balls". United States. https://www.osti.gov/servlets/purl/872069.
@article{osti_872069,
title = {Method and apparatus for jetting, manufacturing and attaching uniform solder balls},
author = {Yost, Frederick G and Frear, Darrel R and Schmale, David T},
abstractNote = {An apparatus and process for jetting molten solder in the form of balls directly onto all the metallized interconnects lands for a ball grid array package in one step with no solder paste required. Molten solder is jetted out of a grid of holes using a piston attached to a piezoelectric crystal. When voltage is applied to the crystal it expands forcing the piston to extrude a desired volume of solder through holes in the aperture plate. When the voltage is decreased the piston reverses motion creating an instability in the molten solder at the aperture plate surface and thereby forming spherical solder balls that fall onto a metallized substrate. The molten solder balls land on the substrate and form a metallurgical bond with the metallized lands. The size of the solder balls is determined by a combination of the size of the holes in the aperture plate, the duration of the piston pulse, and the displacement of the piston. The layout of the balls is dictated by the location of the hooks in the grid. Changes in ball size and layout can be easily accomplished by changing the grid plate. This invention also allows simple preparation of uniform balls for subsequent supply to BGA users.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Jan 01 00:00:00 EST 1999},
month = {Fri Jan 01 00:00:00 EST 1999}
}