Case Study – Acetone Replacement in Photoresist Strip Process
Case Study Summary:
Sta-Sol ME 1100C is a water-soluble, microemulsion concentrate used as a flexible ingredient in industrial cleaning formulations and solvent replacement applications.
Our customer recently tested this product as a safer alternative to acetone in a positive photo resist strip for their microelectronics fabricating operation.
Sta-Sol® ME 1100C exceeded their performance expectations, while offering a safer, water-soluble stripping alternative to acetone.
Our customer, specializing in advanced microelectronics fabrication, was using acetone bath immersions for its positive photo resist strip process. Acetone is an aggressive and effective solvent for this application, and using it was a standard practice for their industry.
However, acetone is flammable and presents serious safety concerns when used in a closed cleaning environment.
We began working with our customer to supply safer solvent alternatives to acetone.
Our initial solvent samples were effective in replacing acetone in the company’s positive photo resist strip applications.
However, our solvents were only slightly water soluble.
As the company used a water rinse immediately after solvent exposure, our solvent would require an additional step to emulsify the solvent, in a separate bath immersion, prior to rinsing.
The customer needed a more efficient, water soluble acetone alternative that would also satisfy performance and safety requirements.
Testing Sta-Sol® Microemulsions
After learning more about the water solubility requirements of the company’s unique application environment, we provided more information about certain products within our line of Sta-Sol® microemulsions.
Microemulsion concentrates deliver solvency in a concentrated, water-soluble solution.
A microemulsion concentrate such as 1100C can retain solvent cleaning performance when diluted with water, often at high water to actives ratios, and provides a cost-effective alternative when compared to using 100% active solvent in a cleaning operation.
In addition to performance and water solubility, Sta-Sol® ME products have preferable environmental, health and safety profiles when compared to certain volatile and/or flammable cleaning solvents, such as acetone.
For example, Sta-Sol® ME 1100C is non-flammable and has a very low vapor pressure. It can be used as is or diluted with water, up to 100%.
It is also a flexible ingredient for more advanced formulations and is compatible with a wide range of additives, extenders and co-solvents.
Ultimately, the customer decided to test Sta-Sol® ME 1100C in their positive photo resist strip applications and began evaluating the product over the course of several months.
Sta-Sol ME 1100C Replaces Acetone
During testing and solvent evaluation, our customer found that ME 1100C enabled them to maintain stripping performance, improve upon the safety of using cleaning solvents, and remain efficient in their cleaning and rinsing procedure.
Ultimately, the company chose to replace acetone and use Sta-Sol® ME 1100C as the primary cleaning solvent solution in their microelectronics processes.
If you are interested in learning more about Sta-Sol® ME microemulsions for photo resist stripping, or other alternative solvent solutions for a different industrial cleaning application, please feel free to contact us.
Samples are available as well.