ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTNuclear spin polarization effects in systems with large hyperfine couplings. Limitations of Kaptein's rulesRichard S. Hutton, Heinz D. Roth, and Steven H. BertzCite this: J. Am. Chem. Soc. 1983, 105, 21, 6371–6377Publication Date (Print):October 1, 1983Publication History Published online1 May 2002Published inissue 1 October 1983https://pubs.acs.org/doi/10.1021/ja00359a001https://doi.org/10.1021/ja00359a001research-articleACS PublicationsRequest reuse permissionsArticle Views70Altmetric-Citations16LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
Using terpolymers of Poly(norbornene-alt-malefic anhydride-co-acrylic acid) [P(NB/MA/AA)], the dissolution inhibition mechanism for two types of common additives in 193nm resist formulations, tert-butylcarboxylate (e.g. tert-butyl cholate) dissolution inhibitors (DI) and onium salt photoacid generators (PAC's) were examined. For simple cholate ester derivatives, increasing interactions with maleic anhydride repeating units paralleled the dissolution inhibition (tert-butyllithocholate>tert-butyldeoxycholate>tert-butylcholate). For a wider range of cholate derivatives, increasing hydrophobicity as measured by logPoct or the cloud point formation in water/acetone mixtures, is a good predictor of increased dissolution inhibition. Increases in dissolution promotion appeared to track with the number of carboxylic acid moieties and the hydrophobicity of carboxylic acid moieties released upon acidolytic cleavage of carboxylate esters. Finally, for onium salt PAC's, increasing the size of fluorinated anions decreased dissolution inhibition. This may be because these anions offer more steric hindrance, which disfavors interactions with the terpolymer matrix. The nature of this interaction may be that of a PAG with carboxylic acid as judged from modeling studies with acetic acid in which increasing strength of the interaction correlated with increased dissolution inhibition (triflate>nonaflate> perflurooctanesulfonate)
The surface composition of chemically amplified photoresists depends upon the photoacid generator used and the processing. We have used x-ray photoelectron spectroscopy to determine the surface composition of resists using four different photoacid generators: trifluoromethanesulfonate, perfluorobutanesulfonate, perfluorooctanesulfonate, and perfluorobenzenesulfonate. The fluorine in each of these PAGs was used as a tag of their presence on the surface. The surface F concentration generally increased after post- exposure bake. The F concentration tended to increase further after a short bake, but usually decreased after longer baking times. These results suggest that the surface concentration of F reflected competition between bulk diffusion of the photoacid leading to surface segregation and its volatilization.
We describe the fabrication of the world's smallest fully functional conventional non-volatile memory device using 193 nm lithography for all levels. The cell area of the smallest devices fabricated was 0.0896 micrometers 2. The critical level of the device, to define the channel length, was exposed with an alternating aperture phase shift mask. Floating gate dimensions ranged from 0.080 to 0.14 micrometers . Subsequent lithography, to define the control gate utilized a binary mask with gate dimensions down to 0.16 micrometers . A multi-layer ARC was used to reduce substrate reflections and maintain linewidth control over topography. All levels were exposed with a new single layer chemically amplified resist developed for 193 nm lithography. We will present results for line width control, etch bias, implementation of resolution enhancement techniques as well as issues with process integration.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTChemically induced dynamic nuclear polarization from the selective recombination of radical pairs in micellesRichard S. Hutton, Heinz D. Roth, Bernhard Kraeutler, William R. Cherry, and Nicholas J. TurroCite this: J. Am. Chem. Soc. 1979, 101, 8, 2227–2228Publication Date (Print):April 1, 1979Publication History Published online1 May 2002Published inissue 1 April 1979https://pubs.acs.org/doi/10.1021/ja00502a062https://doi.org/10.1021/ja00502a062research-articleACS PublicationsRequest reuse permissionsArticle Views47Altmetric-Citations22LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
Plasma polymerized methylsilane (PPMS) films exposed to UV light in the presence of air undergo photo-oxidation to produce a glass-like material, PPMSO, which can be selectively removed using aqueous HF based chemistries. We find that PPMS, used in such positive tone imaging processes, suffers from several drawbacks which make it an unattractive candidate for use as an imaging layer in positive tone resist schemes. We have used infrared and X- ray photoelectron spectroscopy to characterize the PPMS films. We have found evidence for the presence of bridging methylene groups in the Si-Si backbone of the PPMS polymer at the PPMS/Substrate interface. This thin underlayer of a polycarbosilane material is initially deposited in the PPMS CVD process and is insoluble in aqueous or vapor HF contributing to residue after the development. The limitation as to how rapidly PPMS films can be photo- oxidized in the presence of air using high-fluence laser steppers is determined by the rate of oxygen diffusion into the PPMS films during exposure. This reciprocity failure exhibited by PPMS films may limit positive tone PPMS processing from consideration in high-throughput UV based lithography.
