The Design of Resist Materials for 157nm Lithography.

Abstract

The synthesis and characterization of several new fluoropolymers designed for use in the formulation of photoresists for exposure at 157 run will be described. The design of these resist platforms is based on learning from previously reported fluorine-containing materialsl. We have continued to explore anionic polymerizations, free radical polymerizations, metal-catalyzed addition polymerizations and metal-catalyzed copolymerizations with carbon monoxide in these studies. A new, three component design for 157nm resists will alos be presented. The monomers were characterized by vacuum-UV (VUV) spectrometry and polymers characterized by variable angle spectroscopic ellipsometry (VASE). Resist formulations based on these polymers were exposed at the 157 nm wavelength to produce high-resolution images. The synthesis and structures of these new materials and the details of their processing will be presented.

Radical copolymerization of 2‐trifluoromethylacrylic monomers. II. Kinetics, monomer reactivities, and penultimate effect in their copolymerization with norbornenes and vinyl ethers

“…Another discovery, that 2‐trifluoromethylacrylic (TFMA) monomers and norbornenes (NBs) can readily undergo radical copolymerization,4–6 whereas they are both extremely sluggish in radical homopolymerization,8 has provided us with a foundation on which to build 157‐nm resist polymers 4–6. Our report on the radical copolymerization of TFMA with NBs has prompted other research groups to explore this chemistry for the preparation of 157‐nm resist polymers 9–12. Furthermore, we have found that vinyl ethers (VEs) can copolymerize with TFMA by radical initiation 13–15.…”

A study on the dissolution inhibition of poly norbornene hexafluoroisopropanol in aqueous base solutions

“…The second group of inhibitors is (L-series): L1-ter-Butylcarbonatebisphenol A (3,4,5) L2-Di(5-tert-butoxycarbonyl-5-trifluoromethyl-norbonyl)carbonate (3) L3-Di(5-tert-butoxycarbonyl-5-trifluoromethyl-norbonyl)methylcarbonate (3) L4-1,3-Di[tert-butoxycarbonyloxy-1-(trifluoromethyl)-(2,2,2-trifluor)ethyl]cyclohexane (3,4,5) L5-Triphenylsulfonium-bis(triflate)imide (2) L6-Triphenylsulfonium-bis(pentaflate)imide (2) L7-Triphenylsulfonium-bis(nonaflate)imide (2) L8-Bis-ter-butylphenyliodonium-bis(triflate)imide (2) L9-Bis-ter-butylphenyliodonium-bis(pentaflate)imide (2) L10-Bis-ter-butylphenyliodonium-bis(nonaflate)imide (2) Diazonaphthoquinone (DNQ) inhibitors were not used in this study due to compatibility problems with PNBHFA, particularly experienced at high concentrations.…”

“…Increased interest in the dissolution behavior of poly norbornene hexafluoroisopropanol (PNBHFA) and other hexafluoroisopropanol (HFA) bearing polymers in aqueous base developers is evident by recent publications (1), (2), (3), (4), (5) . Fluorinated polymers are considered an important platform for 157nm resist development due to their low absorption at 157nm.…”

Development of Novel Photo-Functional Materials Based on Cyclic Oligomers

“…51,52 It was suggested that molecular size is an important consideration to achieve higher resolution, from the viewpoints of both photoreactivity and low line-edge roughness. 43 We designed new CD derivatives containing fluorine and tbutyl ester moieties as candidate high-performance ArF photoresist materials, 53 because we expected that CD derivatives would show good transmittance of vacuum ultraviolet (VUV) laser light. The Michael addition reaction of -cyclodextrin (-CD) and t-butyl--(trifluoromethyl)acrylate (BTMA) was examined using Cs 2 CO 3 as a base and tetrabutylammonium bromide (TBAB) as a phase transfer catalyst in DMSO at 25 C for 6 h, to give -CD derivatives containing fluorine atoms, tbutyloxycarbonyl groups, and hydroxyl groups (Scheme 6).…”

“…The chemical amplification resist system is one new approach. [42][43][44][45][46] In this system, acid derived from a photo-acid generator promotes removal of the protecting groups, such as tbutyl ester, acetal, trimethylsilyl, and tetrahydropyranyl groups to achieve higher resolution. [47][48][49][50] Recently, many new chemical The n D 's of the calixarene derivative films about 0.1 mm thick, spincoated on a silicon wafer, before and after photo-irradiation were determined by ellipsometry at 632.8 nm.…”