ISSN:1042-7147    

DOI:10.1002/pat.1994.220050101

出版商:John Wiley&Sons, Ltd.    

年代:1994

数据来源: WILEY

摘要:

AbstractPositive photoresist systems comprising phenolic resin and quinonediazide are studied in detail. The structure of several novolak resins, which were synthesized from multi‐substituted phenols, are analyzed with13C‐NMR. It is proved that these phenols are useful for the structural control of novolak resins. Phenols with two methyl substituents at meta‐positions especially show a remarkable structural effect to control methylene bond types of novolak resins.The alkaline dissolution rate is also investigated on novolak resins synthesized from multi‐substituted phenols to understand both the dissolution inhibition effect and the dissolution promotion effect. Key‐structure of novolak resins for realizing high resolution is elucidated.In addition, the molecular design concept of novolak resin is clarified from several standpoints. Unsubstituted aromatic carbon of resin, hydrophobic effect of methyl substitutent and suitable structure of low Mwparts of novolak resin are also explored.Furthermore, it is proposed that a resist using a resin, which is based on the molecular design concept, has enough potential to produce critical dimensions of 0.2 μm or less taking advantage of phase‐shiftin

ISSN:1042-7147    

DOI:10.1002/pat.1994.220050102

出版商:John Wiley&Sons, Ltd.    

年代:1994

数据来源: WILEY

摘要:

AbstractA review of recent efforts to develop photoresist materials and processes for 193 nm (ArF excimer laser) photolithography is reported. Three categories of resist processes are discussed: (1) conventional single layer, (2) bilayer and (3) surface‐imaged resist processes. To date, materials have been developed for each process which exhibit resolution to less than 0.25 μm with sensitivities of less than 50 mJ/c

ISSN:1042-7147    

DOI:10.1002/pat.1994.220050103

出版商:John Wiley&Sons, Ltd.    

年代:1994

数据来源: WILEY

摘要:

AbstractHeat transfer in a resist‐coated silicon wafer using a bake process is theoretically evaluated by modeling the three‐dimensional diffusion process, focusing on the controllability of the lithographic performance of chemically amplified resists. Six models of various ambient conditions are used. The proximity gap between the hotplate and the wafer is found to have a dominant influence on the heat transfer process for the whole system. Because the atmosphere near the wafer acts as a thermal diffusion buffer layer, no temperature gradient occurs in the resist, even when it is subjected to convective heat transfer from the resist surface. Experimental results obtained by X‐ray lithography confirm the calculation re

ISSN:1042-7147    

DOI:10.1002/pat.1994.220050104

出版商:John Wiley&Sons, Ltd.    

年代:1994

数据来源: WILEY

摘要:

AbstractThe synthesis and lithographic characterization of the three positional isomers of polyhydroxystyrene is described. Large differences in dissolution rates are found as a function of the position of the hydroxy group, which are explained in terms of intra‐ vs. intermolecular hydrogen bonding and steric shielding of the hydroxy group by the polymer backbone. In plots of log (dissolution rate) vs. developer strength, linear plots are observed for the 2‐ and 4‐isomers, while for poly(3‐hydroxystyrene), a break occurs in the plot, leading to two linear regions. While the 2‐hydroxy isomer is too slow and the 4‐hydroxy isomer too fast for use in conventional dissolution inhibition systems, the copolymerization of both allows any dissolution rate between these extremes to be chosen ( “dial a dissolution rate” copolymers). Determination of the copolymerization parameters of the corresponding 4‐ and 2‐acetoxystyrene precursors by the method of Kelen and Tüdös shows the polymerization to be nearly ideal and azeotropic (r1= 0.76, r2= 0.94). Analysis of the dissolution rates as a function of developer strength according to the Huang–Reiser–Kwei equation shows that the critical concentrations c*are a linear function of copolymer composition, whereas the penetration exponents in show a minimum near unity in the region of the 1 : 1 copolymer, down from the values of 3.2–3.3 observed for all three homopolymers. The 1 : 1 copolymer shows a dissolution rate comparable to novolak resins, and when formulated into a photoresist together with a diazonaphthoquinone sensitizer resolved 0.4μm features at a dose of 340 mJ/cm2. The thermal flow resistance of the resist was found to be improved over that of novolak resists although not to the degree expected from the incr

ISSN:1042-7147    

DOI:10.1002/pat.1994.220050105

出版商:John Wiley&Sons, Ltd.    

年代:1994

数据来源: WILEY

摘要:

AbstractPolymers obtained by radical polymerization of maleic anhydride with different monomers are used in bilayer photoresists for the CARL (Chemical Amplification of Resist Lines) process. Aqueous‐based silylation of resist patterns with bisaminopropyl‐oligodimethylsiloxane enhances oxygen–plasma etch resistance and creates widened structures. Thus, the resolution capability of optical exposure tools can be used to the full extent and even structures beyond the optical resolution limit become accessible. Copolymerization of maleic anhydride with tBOC‐maleimide or methacrylic acid t‐butylester yields polymers for highly sensitive acid‐catalyzed deep UV resists. With the use of a KrF excimer‐laser stepper 0.25 μm structure

ISSN:1042-7147    

DOI:10.1002/pat.1994.220050106

出版商:John Wiley&Sons, Ltd.    

年代:1994

数据来源: WILEY

摘要:

AbstractThe X‐ray (1.4 nm) and deep UV (248 nm) radiation responses of chemically amplified photoresists incorporating arylmethyl sulfone photoacid generators were evaluated. The arylmethyl sulfones were primarily derivatives of benzyl phenyl sulfone, selected to reveal the importance of desulfonylation and internal abstraction with regard to the photochemical efficiency of acid generation. At 1.4 nm, benzyl phenyl sulfone gave a much more sensitive resist than dibenzyl sulfone, while the methyl derivatives of benzyl phenyl sulfone did not give much improvement over the parent compound. This suggests that desulfonylation is more important than internal abstraction for increased photochemical efficiency. At 248 nm, similar trends were observed, but with some modifications arising from the variation in extinction coefficient among the sulfones. Sensitivities at or below 20 mJ/cm2were obtained for both wavelength range

ISSN:1042-7147    

DOI:10.1002/pat.1994.220050107

出版商:John Wiley&Sons, Ltd.    

年代:1994

数据来源: WILEY

摘要:

AbstractThe design of an efficient photosenzitizer/photoinitiator combination is partly governed by a better understanding of the excited state processes involved. In the present paper, the photochemistry of a thiopyrylium salt (TP) as photosensitizer and of a tetraperester of benzophenone, tetra t‐butyl peroxycarbonylbenzophenone (BTTB) as initiator, used in laser imaging applications has been investigated. The reactivity of the triplet states of both compounds BTTB and TP was studied by time‐resolved laser absorption spectroscopy. The laser excitation of TP leads to a long‐lived triplet state (lifetime 20–25 μsec) and a second species arising from the triplet state which cannot yet be characterized. Under laser excitation, BTTB gives a longlived transient arising from the cleavage of the peroxy bond. The short‐lived triplet state cannot be observed on the nanosecond timescale. The triplet state lifetime has been evaluated from quenching experiments and found to be about 1 ns in acetonitrile. The deactivation of the TP triplet state by BTTP was considered, the deactivation constant was found to be equal to 6.6 × 107m−1/sec in acetonitrile. The initiation mechanism

ISSN:1042-7147    

DOI:10.1002/pat.1994.220050108

出版商:John Wiley&Sons, Ltd.    

年代:1994

数据来源: WILEY

摘要:

AbstractPhotoinduced loss of one or both ligands from bis(arene) metal complexes provides an attractive route to cationic Lewis acids that can function as initiators for polymerization and crosslinking reactions. In this article, we examine the spectroscopy, photochemistry and photoinitiation activity of two such complexes: Fe(mes)22+(mes is mesitylene) and Cr(tol)2+(tol is toluene). Acetonitrile solutions of Fe(mes)22+undergo photochemical loss of both mesitylene rings to yield solvated Fe2+. The quantum efficiency of deligation ranges from 0.6 to 1.0 depending upon excitation wavelength, but is independent of complex concentration, solvent, oxygen concentration and excess counter‐ion. Reaction appears to occur from both ligand field and ligand‐to‐metal charge transfer excited states. Low thermal stability, however, limits the use of Fe(mes)22+as a practical photoinitiator. Deligation of both arene rings also occurs upon 366 nm irradiation of Cr(tol)2+in acetonitrile. The quantum efficiency for this process is 0.04 and is independent of oxygen concentration. Photoinitiated crosslinking and insolubilization occur in a thin film of COP (copolymer of glycidyl methacrylate and ethyl acrylate) containing Cr(t

ISSN:1042-7147    

DOI:10.1002/pat.1994.220050109

出版商:John Wiley&Sons, Ltd.    

年代:1994

数据来源: WILEY

摘要:

AbstractRecent developments in the chemistry of organosilicon polymers for use as oxygen plasma‐resistant imaging materials in microlithography are reviewed. Various classes of resists, grouped according to molecular structure, are described with special emphasis on properties critical in microlithographic applications. In addition, several silylation schemes involving selective silylation of a non‐silicon‐containing resist material following patternwise exposure to actinic radiation are also desc

ISSN:1042-7147    

DOI:10.1002/pat.1994.220050110

出版商:John Wiley&Sons, Ltd.    

年代:1994

数据来源: WILEY