Browse by author
Lookup NU author(s): Nathan Brockie,
Dr Alton Horsfall
Full text for this publication is not currently held within this repository. Alternative links are provided below where available.
SU-8 is an epoxy-based, negative photoresist that is widely used in the manufacturing of micromechanical systems. The polymer cross-linking that occurs during the photolithographic processing of SU-8 can result in high levels of stress in the patterned film. This has significant implications for the yield and reliability of SU-8 structures and needs to be understood if the material is to be integrated with other technologies. This paper describes micromechanical test structures that provide the opportunity to wafer map the stress in SU-8 at different stages of the process. The structures are fabricated in a thick layer of SU-8 and are subsequently released from the underlying substrate using a dry chemical vapor etch process. An automated optical measurement system has been built to allow rapid optical inspection of many thousands of test structures fabricated on 200mm wafers. Initial results indicate significant tensile stress in the SU-8, which demonstrates a radial variation along with a dependence on the process conditions.
Author(s): Smith S, Brockie NL, Murray J, Schiavone G, Wilson CJ, Horsfall AB, Terry JG, Stevenson JTM, Mount AR, Walton AJ
Publication type: Article
Publication status: Published
Journal: IEEE Transactions on Semiconductor Manufacturing
Print publication date: 31/07/2012
ISSN (print): 0894-6507
ISSN (electronic): 1558-2345
Altmetrics provided by Altmetric