CERES printing solutions preparation
A CERES printing session require two solutions:
- supporting electrolyte
- CERES electrolyte
A step by step guide on how to prepare the supporting and CERES electrolyte for copper printing is given.
Note
Specifically developed CERES printing solutions are available.
Copper printing standard solutions
Equipment
- 100 ml volumetric flask or graduate cylinder
- micropipette
- laboratory analytical scale
Note
The use of graduate beakers and Erlenmeyer flask for volumetric measurements should be avoided.
Chemicals
The following chemical products are required:
-
H2SO4 96% sulfuric acid
-
HCl 0.5 mM hydrochloric acid
-
CuSO4 · 5 H2O copper sulphate pentahydrate
-
H2O deionized water
Note
The purity of deionized water is usually sufficient, but ultrapure water of type 1 ASTM (D1193-91) with a resistivity of 18.2 MΩ·cm at 25 °C is suggested.
In case a 0.5 mM HCl solution is not on hand, it can be prepared by dilution of a 25% concentrated solution:
- Add 65 µl (73 mg) 25% HCl to 1 lt of deionized water
Danger
When handling concentrated acid solution make sure to use suitable personal protective equipment. All chemicals must be used following the handling and storing procedures indicated in the MSDS provided by the supplier.
Waste solutions must be disposed according to local regulations.
Supporting electrolyte preparation
- Add ~ 80 ml of 0.5 mM HCl solution in a 100 ml volumetric flask
- Slowly add 300 µl (0.55 g) of 96% H2SO4 to the flask
- Fill the flask up to the 100 ml mark with 0.5 mM HCl solution
- Stir the solution for 5 minutes
The supporting electrolyte is a 54 mM solution of sulfuric acid and hydrochloric acid (0.5 mM). For one printing session make sure to have at least 50 ml of supporting electrolyte prepared.
CERES electrolyte preparation
- Add ~ 80 ml of supporting electrolyte in a 100 ml volumetric flask
- Add 12.5 g of CuSO4 · 5 H2O to the flask
- Stir the solution until most of the copper is dissolved
- Fill the flask up to the 100 ml mark with supporting electrolyte
- Stir the solution until the copper is completely dissolved
The CERES electrolyte is a 0.5 M copper sulphate solution in sulfuric acid (51 mM) and hydrochloric acid (0.48 mM).
Note
Preparation steps are not interchangable and the order of operations must be respected