Interconnect alloy material and methods

Patent metadata

Field	Value
Publication number	US-10099307-B2
Application number	US-201715676679-A
Country	US
Kind code	B2
Filing date	Aug 14, 2017
Priority date	Mar 13, 2013
Publication date	Oct 16, 2018
Grant date	Oct 16, 2018

Abstract

A solder and methods of forming an electrical interconnection are shown. Examples of solders include gallium based solders. A solder including gallium is shown that includes particles of other solders mixed with a gallium based matrix. Methods of applying a solder are shown that include swiping a solder material over a surface that includes a resist pattern. Methods of applying a solder are also shown that include applying a solder that is immersed in an acid solution that provides a fluxing function to aid in solder adhesion.

First claim

The invention claimed is:

1. A method, comprising:
forming a resist pattern surrounding an exposed electrical contact;
placing a gallium based solder over the resist pattern and the electrical contact;
wherein the gallium based solder comprises a gallium based matrix and a distribution of dispersed phase particles,
reflowing the gallium based solder on the electrical contact;
and removing the resist pattern.

2. The method of claim 1 , wherein placing a gallium based solder over the resist pattern and the electrical contact includes placing a number of gallium based solder particles suspended in a solvent matrix over the resist pattern and the electrical contact.

3. The method of claim 1 , wherein placing a gallium based solder over the resist pattern and the electrical contact includes placing a composite solder over the resist pattern and the electrical contact, wherein the composite solder includes a liquid gallium based matrix with indium tin solder particles in suspension within the liquid gallium based matrix.

4. The method of claim 1 , wherein placing a gallium based solder over the resist pattern and the electrical contact includes placing a composite solder over the resist pattern and the electrical contact, wherein the composite solder includes a liquid gallium based matrix with copper particles in suspension within the liquid gallium based matrix.

5. The method of claim 4 , wherein a copper fraction in the composite solder is between approximately 1 percent and 30 percent by volume.

6. The method of claim 1 , wherein placing a gallium based solder over the resist pattern and the electrical contact includes placing a liquid gallium based solder suspended in an acid solution over the resist pattern and the electrical contact.

7. The method of claim 1 , wherein placing a gallium based solder over the resist pattern and the electrical contact includes spreading a gallium based solder over the resist pattern and across an array of thousands of electrical contacts.

8. The method of claim 7 , wherein spreading the gallium based solder spreading the gallium based solder across an array of first level interconnect structures in a chip package.

Assignees

• Intel Corp

Inventors

• Zhong Ting
• Baskaran Rajashree Raji
• Aleksov Aleksandar

Classifications

• B23K35/3033

  Ni as the principal constituent · CPC title

• B23K3/0623

  for shaped solder piece feeding, e.g. preforms, bumps, balls, pellets, droplets · CPC title

• B23K3/08

  Auxiliary devices therefor · CPC title

• B23K35/24

  Selection of soldering or welding materials proper (B23K35/34 takes precedence) · CPC title

• B23K35/025 Primary

  Pastes, creams or slurries · CPC title