Dry Film Process Development for Electroplating and Lift-off of Metal Layers
Abstract
A dry film photoresist (MX 5020 from DuPont Electronic Technologies) was selected to fabricate microstructures with high sidewall verticality. Sidewall verticality of dry film is very important for better pattern transfer and sharp features. A fractional factorial design (FFD) method was used to identify the significant process variables for sidewall optimization. The most significant factor was determined to be exposure energy, as other factors were not significant in improving sidewall verticality. It was found that the sidewall slope increased with a decrease in exposure energy. The fabricated dry film molds with nearly vertical sidewalls (86°) were used for copper electroplating and sputter deposited Ti lift-off applications. The electroplating process was also optimized using a fractional factorial design. A lower plating current density resulted in a smoother, fine grained deposit compared to the higher current density, and the dry film resist was able to withstand a very acidic (pH ~1) copper sulfate plating solution. Sputtered titanium films with a thickness of 200 nm were also successfully lifted-off using dry film patterning.
Recommended Citation
P. R. Kanikella et al., "Dry Film Process Development for Electroplating and Lift-off of Metal Layers," Proceedings of SPIE, SPIE, Feb 2008.
The definitive version is available at https://doi.org/10.1117/12.768611
Department(s)
Materials Science and Engineering
Second Department
Electrical and Computer Engineering
Third Department
Biological Sciences
Keywords and Phrases
Dry Film; Fractional Factorial Design; Sidewall Verticality
Document Type
Article - Conference proceedings
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2008 SPIE, All rights reserved.
Publication Date
01 Feb 2008