Indium compositions
View Patent ↗Indium compositions including hydrogen suppressor compounds and methods of electrochemically depositing indium metal from the compositions onto substrates are disclosed. Articles made with the indium compositions are also disclosed.
1. A method comprising:
a) providing a substrate;
b) providing an indium metal electroplating composition consisting of one or more sources of indium ions in amounts of 10 g/L to 70 g/L; one or more acids or salts thereof; one or more hydrogen suppressing epihalohydrin copolymers, the one or more hydrogen suppressing epihalohydrin copolymers are composed of an epihalohydrin and one or more nitrogen-containing organic compounds; optionally, one or more additives selected from the group consisting of surfactants, chelating agents, levelers and suppressors; and water;
c) immersing the substrate in the indium metal electroplating composition; and
d) electroplating an indium metal on the substrate.
2. The method of claim 1 , wherein the indium metal has a thickness of 0.1 μm or greater.
3. The method of claim 1 , wherein the substrate is chosen from a processing die, lid and a heat spreader.
4. The method of claim 1 , wherein the substrate is chosen from a metal, metal alloy, ceramic and composites of metals and ceramics.
5. The method of claim 1 , wherein the one or more nitrogen-containing compounds are chosen from imidazole, derivatives of imidazole, imidazoline and derivatives of imidazoline.
6. The method of claim 1 , wherein the one or more sources of indium ions are in amounts of 10 g/L to 60 g/L.
7. The method of claim 1 , wherein the one or more acids or salts thereof are chosen from alkane sulfonic acids, aryl sulfonic acids, sulfamic acid, sulfuric acid, carboxylic acids and amino acids.
8. The method of claim 1 , wherein a pH is 0 to 5.
9. The method of claim 8 , wherein the pH is 0.5 to 3.