Indium Corporation

Hongwen Zhang

Ning-Cheng Lee

Francis M Mutuku

Jie Geng

Fen Chen

Joseph Wu

Jonathan Minter

Huaguang Wang

Samuel Lytwynec

Some implementations of the disclosure are directed to low melting temperature (e.g., liquidus temperature below 210° C.) SnIn solder alloys. A SnIn solder alloy may consist of: 8 to 20 wt % In; greater than 0 wt % to 4 wt % Ag; optionally, one or more of greater than 0 wt % to 5 wt % Sb, greater than 0 wt % to 3 wt % Cu, greater than 0 wt % to 2.5 wt % Zn, greater than 0 wt % to 1.5 wt % Ni, greater than 0 wt % to 1.5 wt % Co, greater than 0 wt % to 1.5 wt % Ge, greater than 0 wt % to 1.5 wt % P, and greater than 0 wt % to 1.5 wt % Mn; and a remainder of Sn.

SnIn solder alloys

Some implementations of the disclosure are directed to low melting temperature (e.g., liquidus temperature below 210° C.) SnBi or Snln solder alloys. A SnBi solder alloy may consist of 2 to 60 wt % Bi; optionally, one or more of: up to 16 wt % In, up to 4.5 wt % Ag, up to 2 wt % Cu, up to 12 wt % Sb, up to 2.5 wt % Zn, up to 1.5 wt % Ni, up to 1.5 wt % Co, up to 1.5 wt % Ge, up to 1.5 wt % P, and up to 1.5 wt % Mn; and a remainder of Sn. A Snln solder alloy may consist of: 8 to 20 wt % In; optionally, one or more of: up to 12 wt % Bi, up to 4 wt % Ag, up to 5 wt % Sb, up to 3 wt % Cu, up to 2.5 wt % Zn, up to 1.5 wt % Ni, up to 1.5 wt % Co, up to 1.5 wt % Ge, up to 1.5 wt % P, and up to 1.5 wt % Mn; and a remainder of Sn.

SnBi and SnIn solder alloys

High reliability leadfree solder alloys for harsh service conditions are disclosed. In some embodiments, a solder alloy comprises 2.5-4.0 wt % Ag; 0.4-0.8 wt % Cu; 5.0-9.0 wt % Sb; 1.5-3.5 wt % Bi; 0.05-0.35 wt % Ni; and a remainder of Sn. In some embodiments, an apparatus comprises: a component comprising: a main ceramic body, and a side surface having disposed thereon an electrode and a thermal pad; a copper substrate; and a solder alloy electrically coupling the component and the copper substrate, wherein the solder alloy comprises: 2.5-4.0 wt % Ag; 0.4-0.8 wt % Cu; 5.0-9.0 wt % Sb; 1.5-3.5 wt % Bi; 0.05-0.35 wt % Ni; and a remainder of Sn. In some embodiments, an apparatus comprises: a light-emitting diode (LED) component; a Metal Core Printed Circuit Board (MCPCB); and a solder alloy electrically coupling the LED component and the MCPCB, wherein the solder alloy comprises: 2.5-4.0 wt % Ag; 0.4-0.8 wt % Cu; 5.0-9.0 wt % Sb; 1.5-3.5 wt % Bi; 0.05-0.35 wt % Ni; and a remainder of Sn.

High reliability leadfree solder alloys for harsh service conditions

Some implementations of the disclosure relate to a lead-free solder paste with mixed solder powders that is particularly suitable for high temperature soldering applications involving multiple board-level reflow operations. In one implementation, the solder paste consists of 10 wt % to 90 wt % of a first solder alloy powder, the first solder alloy powder consisting of an SnSbCuAg solder alloy that has a wt % ratio of Sn:Sb of 0.75 to 1.1; 10 wt % to 90 wt % of a second solder alloy powder, the second solder alloy powder consisting of an Sn solder alloy including at least 80 wt % of Sn; and a remainder of flux.

Lead-free solder paste with mixed solder powders for high temperature applications

Implementations of the disclosure are directed to a lead-free mixed solder powder paste suitable for low temperature to middle temperature soldering applications. The lead-free solder paste may consist of: an amount of a first solder alloy powder between 44 wt % and 83 wt %, the first solder alloy powder comprising Sn; an amount of a second solder alloy powder between 5 wt % to 44 wt %, the second alloy powder comprising Sn, where the first solder alloy powder has a liquidus temperature lower than a solidus temperature of the second solder alloy powder; and a remainder of flux. The solder paste may be used for reflow at a peak temperature below the solidus temperature of the higher solidus temperature solder powder but above the melting temperature of the lower solidus temperature one.

Low temperature melting and mid temperature melting lead-free solder paste with mixed solder alloy powders

A lead-free solder preform includes a core layer and adhesion layer coated over surfaces of the core layer, where the preform delivers the combined merits from constituent solder alloys of the core and adhesion layers to provide both high temperature performance and improved wetting in high-temperature solder applications such as die attach. The core layer may be formed of a Bi Alloy having a solidus temperature above 260&#xb0; C., and the adhesion layer may be formed of Sn, a Sn alloy, a Bi alloy, In, or an In alloy having a solidus temperature below 245&#xb0; C. The solder preform may be formed using techniques such as: (1) electroplating a core ribbon with an adhesion material, (2) cladding an adhesion material foil onto a core ribbon, and/or (3) dipping a core ribbon in a molten adhesion alloy bath to allow thin layers of adhesion material to adhere to a core ribbon.

Hybrid high temperature lead-free solder preform

A braided solder wire rope includes a first alloy including Bi&#x2014;Ag, Bi&#x2014;Cu, Bi&#x2014;Ag&#x2014;Cu, or Bi&#x2014;Sb; and the second alloy including Sn, In Sn&#x2014;Ag, Sn&#x2014;Cu, Sn&#x2014;Ag&#x2014;Cu, Sn&#x2014;Zn, Bi&#x2014;Sn, Sn&#x2014;In, Sn&#x2014;Sb or Bi&#x2014;In, such that the second alloy controls an interface reaction chemistry with various metallization surface finish materials without interfering with a high temperature performance of the first alloy. The first alloy may have a solidus temperature around 258&#xb0; C. and at least the first alloy of the first wire and the second alloy of the second wire may be braided together.

Hybrid lead-free solder wire

A solder paste consists of an amount of a first solder alloy powder between 60 wt % to 92 wt %; an amount of a second solder alloy powder greater than 0 wt % and less than 12 wt %; and a flux; wherein the first solder alloy powder comprises a first solder alloy that has a solidus temperature above 260&#xb0; C.; and wherein the second solder alloy powder comprises a second solder alloy that has a solidus temperature that is less than 250&#xb0; C.

Mixed alloy solder paste

A lead-free solder wire includes a core wire with a first alloy and a shell coating layer with a second alloy. The first alloy may be composed of Bi&#x2014;Ag, Bi&#x2014;Cu, Bi&#x2014;Ag&#x2014;Cu, or Bi&#x2014;Sb; and the second alloy may be composed of Sn, In Sn&#x2014;Ag, Sn&#x2014;Cu, Sn&#x2014;Ag&#x2014;Cu, Sn&#x2014;Zn, Bi&#x2014;Sn, Sn&#x2014;In, Sn&#x2014;Sb or Bi&#x2014;In, such that the shell coating layer is applied to a surface of the core wire. In another implementation, the lead free solder wire may include a first wire with a first alloy and a second wire with a second alloy. The first alloy may be composed of Bi&#x2014;Ag, Bi&#x2014;Cu, Bi&#x2014;Ag&#x2014;Cu, or Bi&#x2014;Sb; and the second alloy may be composed of Sn, Sn&#x2014;Ag, Sn&#x2014;Cu, Sn&#x2014;Ag&#x2014;Cu, Sn&#x2014;Zn, Bi&#x2014;Sn, Sn&#x2014;In, Sn&#x2014;Sb or Bi&#x2014;In, such that the first alloy of the first wire and the second alloy of the second wire are braided together.

A solder paste consists of an amount of a first solder alloy powder between 44 wt % to less than 60 wt %; an amount of a second solder alloy powder between greater than 0 wt % and 48 wt %; and a flux; wherein the first solder alloy powder comprises a first solder alloy that has a solidus temperature above 260&#xb0; C.; and wherein the second solder alloy powder comprises a second solder alloy that has a solidus temperature that is less than 250&#xb0; C. In another implementation, the solder paste consists of an amount of a first solder alloy powder between 44 wt % and 87 wt %; an amount of a second solder alloy powder between 13 wt % and 48 wt %; and flux.

A solder paste comprises an amount of a first solder alloy powder between about 60 wt % to about 92 wt %; an amount of a second solder alloy powder greater than 0 wt % and less than about 12 wt %; and a flux; wherein the first solder alloy powder comprises a first solder alloy that has a solidus temperature above about 260&#xb0; C.; and wherein the second solder alloy powder comprises a second solder alloy that has a solidus temperature that is less than about 250&#xb0; C.

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New Hartford, NY, United States of America

Hongwen Zhang