Query: GBLMA

title: Enzymatic acrylation of 2 hydroxy g butyrolactone to synthesize the gamma butyrolactone methacrylate (GBLMA) for photoresist
abstract: Lipase mediated acrylation has gained much attention instead of traditional chemical process, since it enables specific catalysis under benign conditions. The effect of acyl donors on the acrylation of 2 hydroxy g butyrolactone by Novozym 435 (immobilized lipase B from Candida antarctica) was investigated. Among acyl donors, vinyl methacrylate was selected to synthesize g butyrolactone methacrylate (GBLMA) The effects of solvent and reaction temperature on the acrylation using vinyl methacrylate were presented. The highest rate of conversion was obtained using methyl tert butyl ether >80% as a solvent, of which a log P value is greater than other solvents tested. The conversion rate increased as the reaction temperature rose from 30 to 60degC and the conversion rate approached 95% at 60oC. The gamma butyrolactone methacrylate (GBLMA) synthesized with vinyl methacrylate at optimized conditions, in which MTBE is used as a solvent and the reaction is carried out at 60degC can be applicable as a monomer for synthesis of photoresist resin.

title: Positive ArF resist with 2EAdMA/GBLMA resin system
abstract: We compared 2MAdMA(2 Metyl 2 Adamantylmethacrylate)/GBLMA((gamma) butyrolactone methacrylate) resin system and 2EAdMA(2 Etyl 2 Adamantylmethacrylate)/GBLMA resin system. 2EAdMA/GBLMA resin system showed higher sensitivity, dissolution contrast and better adhesion to silicon substrate than 2MAdMA/GBLMA resin system. These results shows that 2EAdMA/GBLMA resin system is suitable for practical ArF positive resist.

title: Nitroxide mediated polymerization of adamantyl functional methacrylates for 193 nm photoresists
abstract: Three different methacrylic monomers (g butyrolactone methacrylate (GBLMA) 3 hydroxyl 1 adamantyl methacrylate (HAMA) and 2 methyl 2 adamantyl methacrylate (MAMA) that are most often terpolymerized for 193 nm photoresists, were studied individually by nitroxide mediated polymerization (NMP) with succinimidyl ester terminated BlocBuilder (NHS BlocBuilder) using a small fraction 0.05 mol/mol 5 mol in the initial mixture of 2,3,4,5,6 pentafluorostyrene (PFS) controlling co monomer. The copolymerizations were done in 0.35 g/g (35 wt% dioxane solution and were studied as functions of temperature (75 versus 90 degC) and added free SG1 nitroxide (none versus SG1:NHS BlocBuilder molar ratio 0.15) with the objective of minimizing the dispersity (M w/M n) MAMA/PFS copolymerizations were not strongly influenced by temperature or addition of free nitroxide, with relatively linear number average molecular weight M n versus conversion plots and M w/M n=1.28 1.55. Further, MAMA/PFS polymerization kinetics was notably slower compared to GBLMA or HAMA copolymerizations with PFS. For GBLMA/PFS and HAMA/PFS copolymerizations, M w/M n was reduced the lower temperature of 75 degC but added SG1 did not play a strong role. For GBLMA/PFS, M w/M n was reduced from 1.70 1.71 at 90 degC to 1.42 1.50 at 75 degC and for HAMA/PFS, M w/M n was reduced from 1.36 1.47 at 90 degC to 1.22 1.31 at 75 degC. This article is protected by copyright. All rights reserved

title: A photoacid generator integrated terpolymer for electron beam lithography applications: sensitive resist with pattern transfer potential
abstract: While developing a new resist for different lithography applications, starting from high to low nodes, the potential of the resist in successful pattern transfer has been the key for practical applications particularly in semiconductor industries. Although semiconductor industries are looking for materials for sub 7 nm node technology for sophisticated electronic appliances, the materials with potential for high resolution larger node pattern transfer are equally important for specialized applications in CMOS technology. In this regard, a new ionic photoacid generator included terpolymer photoresist viz GBLMA MAMA MAPDST has been synthesized for next generation lithography (NGL) applications. Electron beam lithography (EBL) studies of this resist coated thin films have shown that the resist can pattern 100 nm line/space features under e beam exposure. The sensitivity (E0) and contrast (g) were calculated to be 36.5 mC cm 2 and 0.08 respectively. Finally, transfer of 100 nm (line/space) patterns into a silicon substrate has been achieved using a dry plasma etching technique.

title: Synthesis of well defined photoresist materials by SET LRP
abstract: Single electron transfer living radical polymerization (SET LRP) provides an excellent tool for the straightforward synthesis of well defined macromolecules. Heterogeneous Cu(0) catalysis is employed to synthesize a novel photoresist material with high control over the molecular architecture. Poly(g butyrolactone methacrylate) co (methyladamantly methacrylate) was synthesized. Kinetic experiments were conducted demonstrating that both monomers, g butyrolactone methacrylate (GBLMA) and methyl adamantly methacrylate (MAMA) are successfully homopolymerized. In both cases polymerization kinetic is of first order and the molecular weights increase linearly with conversion. The choice of a proper solvent was decisive for the SET LRP process and organic solvent mixtures were found to be most suitable. Also, the kinetic of the copolymerization of GBLMA and MAMA was investigated. Following first order kinetics in overall monomer consumption and exhibiting a linear relationship between molecular weights and conversion a "living" process was established. This allowed for the straightforward synthesis of well defined photoresist polymers.

title: Synthesis of ArF photoresist polymer composed of three methacrylate monomers via reversible addition fragmentation chain transfer (RAFT) polymerization
abstract: AbstractArF photoresist polymers were prepared via reversible addition fragmentation chain transfer (RAFT) polymerization and free radical polymerization (FRP) Three methacrylates with lithographic functionalities including 2 ethyl 2 adamantyl methacrylate (EAdMA) a gamma butyrolactone methacrylate (GBLMA) and 3 hydroxy 1 adamantyl methacrylate (HAdMA) were used as monomer components and 2 cyanoprop 2 yl 1 dithionaphthalate (CPDN) was used as the chain transfer agent (CTA) In both polymerizations, the order of monomer reactivity was GBLMA>HAdMA>>EAdMA. This caused a composition gradient in RAFT polymerization as well as composition inhomogeneity in FRP. The polymers prepared by RAFT polymerization had lower molecular weight distributions and more uniform compositions. The improvement in molecular weight distribution and composition uniformity of the polymers prepared by RAFT polymerization should be beneficial for the ArF lithography process.

title: Tailored star shaped statistical teroligomers via ATRP for lithographic applications
abstract: A series of five star shaped teroligomers consisting of a saccharose core, and arms, composed of a gamma butyrolactone methacrylate (GBLMA) methyl adamantyl methacrylate (MAMA) and hydroxyl adamantyl methacrylate (HAMA) with defined arm length and number of arms were prepared via the core first atom transfer radical polymerization (ATRP) route. The saccharose core was modified with ATRP initiating sites and non reactive sites, enabling the synthesis of star polymers with a smaller arm number but identical core. Star teroligomers were synthesized with narrow molecular weight distributions with low polydispersity indices (PDIs 50% The absence of side reaction and the precise achievement of the target molecular weight indicated excellent control over the reaction. A selected star shaped teroligomer was investigated for the first time as a photoresist material. The delicate conditions of the lithographic process were optimized by a combinatorial approach. The obtained low line edge and line width roughness of the observed pattern demonstrate the potential of the star architecture for this application.

title: Comparison of star and linear ArF resists
abstract: Linear and star shaped ArF photoresists were prepared and preliminary lithographic comparison was performed using electron beam exposure. An oligo initiator based on saccharose forms the core of the star shaped photoresist from which three standard ArF photoresist monomers, a gamma butyrolactone methacrylate (GBLMA) methyl adamantyl methacrylate (MAMA) and hydroxyl adamantyl methacrylate (HAMA) were polymerized. Conditions were adjusted to obtain a low polydispersity, 6 kg/mol star polymer with a degree of polymerization of approximately five mers per arm. For comparison, a linear photoresist control was prepared using the same scheme. The star resist architecture was found to improve roughness without reducing sensitivity or resolution.

title: Photosensitivity and line edge roughness of novel polymer bound PAG photoresists
abstract: Substantially improved photoresist material designs, which can provide higher photosensitivity and precise critical dimension and edge roughness control, will be required to enable the application of next generation lithography technology to the production of future sub 65 nm node IC device generations. The development and characterization of novel material platforms that solve the aforementioned basic problems with chemically amplified resists (CARs) is essential and is already one of the major subjects of modern lithography research. In that regard, we have pursued development of a variety of 193 nm and EUV CARs that contain photoacid generator (PAG) units covalently bonded directly to the resin polymer backbone. However, the detailed structure property relationships that result from this direct attachment of the PAG functional group to the polymer have previously not yet been rigorously characterized. In this work, the lithographic properties of a polymer bound PAG CAR (GBLMA co EAMA co F4 MBS.TPS) and its blended PAG analog resist (GBLMA co EAMA blend F4 IBBS.TPS) were studied and compared. The direct incorporation of PAG functionality into the resist polymer, where the resulting photoacid remains bound to the polymer, showed improved photosensitivity, resolution, and lower LER as compared with the analogous blended PAG resist. The improved resolution and LER were expected due to the restricted photoacid diffusion and uniform PAG distribution provided by direct incorporation of the PAG into the polymer backbone to make a single component resist material. The ability to load higher levels of PAG into the resist provided by this PAG incorporation into the polymer, as compared to the low PAG concentrations attainable by traditional blending approaches, overcomes the sensitivity loss that should result from reduction in photoacid diffusivity and concomitant smaller acid catalytic chain lengths. In fact, the polymer bound PAG resist achieves a faster photospeed than the blended PAG analog material under DUV radiation in the case of the materials reported here while still providing all of the aforementioned improvements such as the improved line edge roughness.

title: Chemical composition distribution analysis of photoresist copolymers and influence on ArF lithographic performance
abstract: For getting information about the distribution of chemical composition, several model polymers were prepared under different polymerization conditions and were measured by critical adsorption point liquid chromatography (CAP LC) In the copolymer system of 8 and 9 (4 oxatricyclo[5.2.1.02,6]decane 3 one) acrylate (OTDA) and 2 ethyl 2 adamantyl methacrylate (EAdMA) the peak shapes of the CAP LC chromatogram varied according to the polymerization condition although they indicated same molecular weight and averaged chemical composition. The difference of the CAP LC elution curves was related to the chemical composition distribution of copolymers for CAP LC measurement combined with proton nuclear magnetic resonance (1H NMR) The terpolymers consisted of a hydroxy g butyrolactone methacrylate (GBLMA) 2 methyl 2 adamantyl methacrylate (MAdMA) and 1 hydroxy 3 adamantyl methacrylate (HAdMA) were prepared under various polymerization conditions. In the terpolymer system that had same molecular weight and average chemical composition, the solubility parameter &dgr; and the dissolution rate were measured. The &dgr; value and the dissolution rate curve were different among these terpolymers. It was suggested that the &dgr; value and the chemical composition distribution of these terpolymers have a significant influence on the lithographic performance.