KEYWORDS: Etching, Absorbance, Carbon, Resistance, System on a chip, Reactive ion etching, Polymers, Image processing, Photoresist materials, Optical lithography
The continued miniaturization of integrated circuit features has been made possible through multilayer patterning processes where different etch steps transfer the patterned photoresist image through various hardmasks and ultimately to the underlying substrate. Spin-on carbons (SOCs) are a type of a solution-dispensable carbon hardmask that can offer excellent resistance to various etch gases for good pattern transfer fidelity, while simultaneously conferring desirable gap fill and planarization properties onto the underlying substrate. We recently reported on the development of a new SOC platform with excellent etch resistance, having a relative reactive ion etch (RIE) rate of 1.08 compared to amorphous carbon. However, one drawback we observed for this polymer was its relatively high absorbance between 400-700 nm which can complicate lithographic alignment. Here we report our work on reducing the absorbance of our SOC platform while maintaining its excellent etch resistance. We identify that the origin of high absorbance is from side reactions that occur during curing and discuss the various polymer modifications or additives that prevent these unwanted processes. We additionally look at any trade-offs that are observed between decreasing absorbance and etch resistance and optimize the SOC’s composition to minimize absorbance while having a minimal effect on its etch resistance.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.