Surface modification of SU-8 for metal/SU-8 adhesion using RF plasma treatment for application in thermopile detectors
2015 (English)In: MATERIALS RESEARCH EXPRESS, ISSN 2053-1591, Vol. 2, no 8, 086501Article in journal (Refereed) PublishedText
This article reports on plasma treatment of SU-8 epoxy in order to enhance adhesive strength for metals. Its samples were fabricated on standard silicon wafers and treated with (O-2 and Ar) RF plasma at a power of 25 W at a low pressure of (3 x 10(-3) Torr) for different time spans (10-70 s). The sample surfaces were characterized in terms of contact angle, surface (roughness and chemistry) and using a tape test. During the contact angle measurement, it was observed that the contact angle was reduced from 73 degrees to 5 degrees (almost wet) and 23 degrees for (O-2 and Ar) treated samples, respectively. The root mean square surface roughness was significantly increased by 21.5% and 37.2% for (O-2 and Ar) treatment, respectively. A pattern of metal squares was formed on the samples using photolithography for a tape test. An adhesive tape was applied to the samples and peeled off at 180 degrees The maximum adhesion results, more than 90%, were achieved for the O-2-treated samples, whereas the Ar-treated samples showed no change. The XPS study shows the formation of new species in the O-2-treated sample compared to the Ar-treated samples. The high adhesive results were due to the formation of hydrophilic groups and new O-2 species in the O-2-treated samples, which were absent in Ar-treated samples.
Place, publisher, year, edition, pages
2015. Vol. 2, no 8, 086501
SU-8, contact angle, plasma treatment, surface modification, adhesion, tape test, theromocouples
Fusion, Plasma and Space Physics
IdentifiersURN: urn:nbn:se:uu:diva-280967DOI: 10.1088/2053-1591/2/8/086501ISI: 000370037800017OAI: oai:DiVA.org:uu-280967DiVA: diva2:912432