Mr. Michael T. Sheehan Profile

Michael T. Sheehan

Technical Consultant

SPIE Involvement:

Author

Publications (4)

Proceedings Article | 29 March 2013 Paper

High chi polymer development for DSA applications using RAFT technology

Michael Sheehan, William Farnham, Hoang Tran, J. David Londono, Yefim Brun

Proceedings Volume 8682, 868225 (2013) https://doi.org/10.1117/12.2018255

KEYWORDS: Polymers, Polymerization, Control systems, Statistical analysis, Molecular self-assembly, Liquids, Materials processing, Chemical analysis, Light scattering, Directed self assembly

Read Abstract +

Proceedings Article | 16 April 2011 Paper

Designing materials for advanced microelectronic patterning applications using controlled polymerization RAFT technology

Michael Sheehan, William Farnham, Charles Chambers, Hoang Tran, Hiroshi Okazaki, Yefim Brun, Matthew Romberger, James Sounik

Proceedings Volume 7972, 79720T (2011) https://doi.org/10.1117/12.882960

KEYWORDS: Polymers, Polymerization, Photoresist materials, Optical lithography, Directed self assembly, Photomasks, Lithography, Photoresist developing, Line width roughness, Microelectronics

Read Abstract +

Proceedings Article | 26 March 2008 Paper

RAFT technology for the production of advanced photoresist polymers

Michael Sheehan, William Farnham, Hiroshi Okazaki, James Sounik, George Clark

Proceedings Volume 6923, 69232E (2008) https://doi.org/10.1117/12.772115

KEYWORDS: Polymers, Photoresist materials, Photomasks, Polymerization, Sodium, Line width roughness, Solids, Semiconducting wafers, Optical lithography, Photoresist developing

Read Abstract +

Proceedings Article | 7 July 1997 Paper

Non-chemically amplified 248-nm resist materials

C. Grant Willson, Wang Yueh, Michael Leeson, Thomas Steinhaeusler, Christopher McAdams, Ralph Dammel, James Sounik, M. Aslam, Richard Vicari, Michael Sheehan

Proceedings Volume 3049, (1997) https://doi.org/10.1117/12.275821

KEYWORDS: Deep ultraviolet, Absorbance, Analog electronics, Chromophores, Lithography, Chemically amplified resists, Ultraviolet radiation, Manufacturing, Lamps, Excimer lasers

Read Abstract +

Remarkable progress has been made in the formulation of chemically amplified resists for deep-UV (DUV or 248 nm) lithography. These materials are now in general use in full scale manufacturing. One of the deterrents to rapid and universal adoption of DUV lithography has been the combination of high cost of ownership and a narrow process latitude when compared to conventional i-line process alternatives. A significant part of the high cost of the DUV process is associated with installing and maintaining special air handling equipment that is required to remove basic contaminants from the ambient. Manufacture process latitude demands this special air handling. The chemically amplified resists were developed originally to support mercury lamp powered exposure systems. The sensitivity realized by chemical amplification is required to enable useful productivity with such systems that generate very little DUV flux at the wafer plane. With the advent of high powered excimer laser based illumination systems for 248 nm steppers and step-and-scan systems, it is appropriate to re-examine the applicability of non-chemically amplified DUV resist systems. These systems are less sensitive but have the potential to offer both lower cost of ownership and improved process latitude. A series of photoactive compounds (PACs) have been synthesized and auditioned for use in the formulation of a non-chemically amplified 248 nm resist. The most promising of these materials are analogs of 3-oxo-3-diazocoumarin. This chromophore displays photochemistry that is analogous to that of the diazonaphthoquinones (DNQ) that are the basis of i-line resist formulations, but it bleaches at 248 nm. Several structural analogs of the chromophore have been synthesized and a variety of ballast groups have been studied with the goal of enhancing the dissolution inhibition properties of the molecule. The diazocoumarin PACs have been formulated with customized phenolic resins that were designed to provide the combination of optical transparency, dry etch resistance and the dissolution characteristics that are required for manufacturing applications. The resins are copolymers of poly(4-hydroxystyrene) and blends of these polymers with novolac.

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Keywords/Phrases

Search In:

Publication Years