Electron-beam-resist materials with enhanced dry etch resistance

Affrossman, S.; Angadji, Hassan; Bakhshaee, M.; Coffey, Kathleen; Chow, Fong Lung; Hayward, D.; McLeod, G.; Pethrick, Richard A.; Whittaker, Paul

doi:10.1016/0032-3861(89)90073-6

Cited by 10 publications

(7 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although Kitayama and Hatada reported stereospecific anionic polymerization of trimethylsilyl methacrylate at low temperature, there have been no studies focusing on the stereospecific radical polymerization of a series of various silyl methacrylates with different bulkiness. In addition, trimethylsilyl and its related silyl methacrylates have been synthesized − and homo- or copolymerized radically or anionically, which were particularly directed to photoresist applications as precursors of PMAA moieties. , …”

Section: Introductionmentioning

confidence: 99%

Stereospecific Free Radical and RAFT Polymerization of Bulky Silyl Methacrylates for Tacticity and Molecular Weight Controlled Poly(methacrylic acid)

2011

View full text Add to dashboard Cite

A series of silyl methacrylates [CH2C(CH3)CO2SiR3] with varying silyl group bulkiness [R3Si: Me3Si, Et3Si, Me2 tBuSi, iPr3Si, Ph2 tBuSi, Ph3Si, and (Me3Si)3Si] were synthesized and radically polymerized to efficiently give soluble polymers with the exception of the highly bulky tris(trimethylsilyl)silyl methacrylate (TTMSSMA), which resulted in insoluble polymers. All the polymers can easily be converted into poly(methacrylic acid) (PMAA) via acid- or fluoride-induced deprotection of the silyl groups and further into poly(methyl methacrylate) (PMMA) via methylation with trimethylsilyldiazomethane for the analysis of molecular weight and tacticity. The tacticity was dependent on the bulkiness of the silyl substituents; the isotacticity increased with increasing bulkiness. Thus, a series of PMAAs and PMMAs with various tacticities ranging from syndiotactic-rich (rr = 74%; Me2 tBuSi) to atactic (mr = 50%; iPr3Si) and highly isotactic [mm = 93%; (Me3Si)3Si] enchainment were obtained by conventional radical polymerization of silyl methacrylates followed by simple postreactions. The high isotacticity and insolubility of poly(TTMSSMA) suggested the formation of helical polymers as in the polymerization of similarly bulky triarylmethyl methacrylate. Reversible addition–fragmentation chain-transfer (RAFT) polymerization also worked for these silyl methacrylates, which resulted in well-defined polymers with controlled molecular weights and various tacticities. RAFT polymerization was further applied to the synthesis of novel stereoblock polymers, such as stereo-triblock PMAA and PMMA that consisted of syndiotactic-rich, atactic, and isotactic stereogradient segments.

show abstract

Section: Introductionmentioning

confidence: 99%

Stereospecific Free Radical and RAFT Polymerization of Bulky Silyl Methacrylates for Tacticity and Molecular Weight Controlled Poly(methacrylic acid)

2011

View full text Add to dashboard Cite

show abstract

“…Curometer measurements traced the reaction in terms of change in viscosity during the polymerization process and used the calculations outlined elsewhere. 20 Data points were taken every second for the duration of the study. The data was collected via the computer program Picolog.…”

Section: Viscosity Measurementsmentioning

confidence: 99%

Redox initiated free radical polymerization of 4‐methylstyrene

Mortamet

Pethrick

2011

J of Applied Polymer Sci

Self Cite

View full text Add to dashboard Cite

Studies of the thermally initiated polymerization of 4-methylstyrene using alkylperoxide in conjunction with cobalt and tertiary amine catalysts are reported. Addition of cobalt salts leads to a facile low temperature initiation of the polymerization process. The polymerization process was investigated using differential scanning calorimetry [DSC] and vibrating probe rheological measurements. Color changes which occur when the cobalt complex and peroxide are combined were studied using UV-visible spectroscopy. The kinetics of polymerization was investigated using two different cobalt complexes. The initiation step in the polymerization is the conversion of the cobalt (II) to cobalt (III). The presence of the tertiary amine does not affect the oxidation state of the cobalt complex. The cobalt (III) complex gives a better rate of conversion than the cobalt (II) complex. The polymerization process is discussed in terms of redox reaction between the cobalt complex and the alkyperoxide. At low temperatures, the rate of conversion obeys simple Arrhenius kinetics. At higher temperatures the effects of gelation and catalysts inhibition influence the polymerization process. The polymerization process is sensitive to the level of available oxygen during the initiation step and inhibition by aldehyde is observed

show abstract

“…In this work, RAFT polymerization was selected to synthesize silylated methacrylic polymers with controlled molecular weight distributions, well‐defined chain architectures, and low polydispersity. Some studies of trialkylsilyl methacrylate homopolymerization and copolymerization have been reported16 for applications in photoresists of polymers,17–19 in dry etch resistance of polymers,20 and in antifouling paints 21–23. However, no studies, until now, have been reported on the living radical polymerization of trialkylsilyl methacrylate monomers.…”

Section: Introductionmentioning

confidence: 99%

Controlled radical polymerization of a trialkylsilyl methacrylate by reversible addition–fragmentation chain transfer polymerization

Nguyen

Bressy

Margaillan

2005

J. Polym. Sci. A Polym. Chem.

View full text Add to dashboard Cite

The reversible addition-fragmentation chain transfer (RAFT) polymerization of a hydrolyzable monomer (tert-butyldimethylsilyl methacrylate) with cumyl dithiobenzoate and 2-cyanoprop-2-yl dithiobenzoate as chain-transfer agents was studied in toluene solutions at 70 8C. The resulting homopolymers had low polydispersity (polydispersity index < 1.3) up to 96% monomer conversion with molecular weights at high conversions close to the theoretical prediction. The profiles of the number-average molecular weight versus the conversion revealed controlled polymerization features with chain-transfer constants expected between 1.0 and 10. A series of poly (tert-butyldimethylsilyl methacrylate)s were synthesized over the molecular weight range of 1.0 Â 10 4 to 3.0 Â 10 4 , as determined by size exclusion chromatography. As strong differences of hydrodynamic volumes in tetrahydrofuran between poly(methyl methacrylate), polystyrene standards, and poly(tert-butyldimethylsilyl methacrylate) were observed, true molecular weights were obtained from a light scattering detector equipped in a triple-detector size exclusion chromatograph. The Mark-Houwink-Sakurada parameters for poly(tert-butyldimethylsilyl methacrylate) were assessed to obtain directly true molecular weight values from size exclusion chromatography with universal calibration. In addition, a RAFT agent efficiency above 94% was confirmed at high conversions by both light scattering detection and 1 H NMR spectroscopy. V V C 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5680-5689, 2005

show abstract

Electron-beam-resist materials with enhanced dry etch resistance

Cited by 10 publications

References 8 publications

Stereospecific Free Radical and RAFT Polymerization of Bulky Silyl Methacrylates for Tacticity and Molecular Weight Controlled Poly(methacrylic acid)

Stereospecific Free Radical and RAFT Polymerization of Bulky Silyl Methacrylates for Tacticity and Molecular Weight Controlled Poly(methacrylic acid)

Redox initiated free radical polymerization of 4‐methylstyrene

Controlled radical polymerization of a trialkylsilyl methacrylate by reversible addition–fragmentation chain transfer polymerization

Contact Info

Product

Resources

About