KR20030008215A - Ultraviolet and Vacuum Ultraviolet Transparent Polymer Compositions and their Uses - Google Patents

Abstract

Partially fluorinated and fully fluorinated polymers are provided that are substantially transparent to ultraviolet light at a wavelength of 140-186 nm.

Description

Ultraviolet and Vacuum Ultraviolet Transparent Polymer Compositions and their Uses}

The semiconductor industry is the foundation of the $ 1 trillion electronics industry. Since most of the optical lithography ability to print smaller features on silicon continues to improve, the semiconductor industry requires Moore's Law to double the integrated circuit density every 18 months. Meets constantly. The circuit pattern is included in the photomask and the mask pattern is projected onto the photoresist layer on the silicon wafer using an optical stepper. Current lithography is done using 248 nm light; Lithography using 193 nm light is just entering early production. Alternative lithography methods that do not use visible or ultraviolet waves, that is, next-generation lithography using X-rays, e-beams or EUV radiation, are not complete enough to be ready for production. Through the international consortium SEMATECH, the industry has concluded that lithography based on 157 nm light will be the next technological step. 157 nm is in a region of the spectrum called vacuum ultraviolet (VUV), spanning 186-50 nm. The use of this VUV lithography requires transparent materials in this range. Specifically, the new 157 nm optical lithography standard requires new polymer materials based on the transparency requirements at 157 nm. As the use of this new technology evolves, there remains a need for improved materials useful at shorter wavelengths.

Certain fluoropolymers have already been identified in the art as being useful for optical applications such as light guides, antireflective coatings and layers, pellicles and glues. Much of this work has been done at wavelengths above 200 nm where perfluoropolymer absorption is of little importance.

WO 9836324 (August 20, 1998; Mitsui Chemicals Inc.) discloses a resin consisting solely of C and F, with a silicone polymer, optionally with a siloxane backbone, with an absorbance of 0.1 to 1.0 at a UV wavelength of 140 to 200 nm. Use as a pellicle membrane having is described. The data for the fluoropolymers listed in the literature along with the Applicant's measurements (see Table 1 below) show that the C and F fluoropolymers at or above 157 nm absorb much greater than A / μ = 0.1 to 1 as claimed in WO 9836324. Prove that you have

WO 9822851 (May 28, 1998; Mitsui Chemicals Inc.) claims to use a photodegradable tacky polymer that immobilizes dust particles when coated on the inner surface of a pellicle frame. This tacky material has a composition consisting predominantly of low molecular weight-(CF ₂ -CXR) copolymers, where X is halogen and R is -Cl or CF ₃ . Poly (perfluorobutenyl vinyl ether), poly [(tetrafluoroethylene / perfluoro- (2,2-dimethyl-1,3-diosol)], poly (tetrafluoroethylene / hexafluoropropylene High molecular weight polymers, such as polyvinylidene fluoride), poly (hexafluoropropylene / vinylidene fluoride), or poly (chlorotolyl fluoroethylene / vinylidene fluoride), to reduce creep resistance All examples of this technique relate to the use of poly (chlorotrifluoroethylene), a low molecular weight adhesive that strongly absorbs light at 157 nm and is illustrated only by extended UV degradation (248 nm). It should be borne in mind that retaining tack, rather than transparency, is the only proven benefit of the claimed formulation.

Japanese Patent No. 07,295,207 (November 10, 1995, Shinetsu Chem. Ind Co.) are more top ^TM CTXS (Cytop CTXS) (poly _{(CF 2 = CFOCF 2 CF 2} CF = CF 2)) between the high strength for Is claimed for a bilayer pellicle in combination with Teflon (R) AF 1600. Teflon® AF 1600 and Cytop ™ both absorb strongly at 157 nm (see Table 2).

U.S. Patent No. 5286567 (Shin-Etsu Chemical Co., Ltd., Feb. 15, 1994) discloses tetrafluoroethylene and 5-membered cyclic perfluoroethers which are made hydrophilic by plasma treatment and thus have antistatic properties. It is claimed to use a copolymer of monomer as a pellicle. It is illustrated in Table 2 that only one fifth of the polymers have been shown to achieve this goal that the five-membered ring monomer and tetrafluoroethylene are not sufficient to provide A / μ <0.1.

EP 416528 (DuPont, March 13, 1991) claims an amorphous fluoropolymer having a refractive index of 1.24-1.41 as a pellicle at a wavelength of 190-820 nm.

Japanese Patent No. 01241557 (September 26, 1989; Bando Chemical Industries, Ltd.) discloses vinylidene fluoride (VF ₂ ), tetrafluoroethylene / hexafluoropropylene (TFE / HFP), ethylene / tetrafluoro (Co) of ethylene (E / TFE), TFE / CF ₂ = CFORf, TFE / HFP / CF ₂ = CFORf, chlorotrifluoroethylene (CTFE), E / CTFE, CTFE / VF ₂ and vinyl fluoride (VF) Claim a pellicle that can be used at 280-360 nm using a polymer.

Japanese Patent No. 59048766 (March 21, 1984; Mitsui Toatsu Chemicals, Inc.) claims to use an elongated film of poly (vinylidene fluoride) having good transparency at 200 to 400 nm.

Many of the fluoropolymers mentioned in these documents are expected to be markedly blurred on the surface due to the crystallinity, which is expected to scatter light to an extent that is unsuitable for high light transmittance and accurate circuit pattern reproduction. Poly (vinylidene fluoride), poly (chlorotrifluoroethylene), poly (tetrafluoroethylene / ethylene), commercial poly (tetrafluoroethylene / hexafluoropropylene) compositions and poly (ethylene / chlorotrifluoro Ethylene) are all such crystalline and optically blurred materials. Thus, more recent literature is focused on Cytop ™ and Teflon® AF because they combine perfluorination with properties of excellent optical clarity, solubility, and complete lack of crystallinity. to be. However, as indicated in the discussion below, most grades of Cytop ™ and Teflon® AF do not have the transparency required at 157 nm.

It is an object of the present invention to overcome the difficulties associated with the prior art by providing partially fluorinated polymers and fully fluorinated polymers which are substantially transparent to ultraviolet light at wavelengths between 140 and 186 nm, in particular 157 nm.

Summary of the Invention

The present invention provides from 0 to 25 mole percent of at least one monomer CR ^a R ^b = CR ^c R ^d (where CR ^a R ^b = CR ^c R ^d enters the homopolymer or copolymer in a nearly random manner) and optionally from 40 to 60 mol% of at least one monomer CR ^a R ^b = CR ^c R ^d (where CR ^a R ^b = CR ^c R ^d enters the copolymer in an almost alternating manner), where R ^a , R ^b and R ^c are Each independently selected from H or F, and R ^d is F, CF ₃ , OR _f (where R _f is C _n F _{2n + 1} , n is 1 to 3) and OH when R ^c = H Perfluoro-2,2-dimethyl-1,3-dioxol or CX ₂ = CY ₂ , wherein X is F or CF ₃ , and Y is H Absorbance / micron at 140-186 nm wavelength including amorphous vinyl homopolymer, or perfluoro-2,2-dimethyl-1,3-dioxol and amorphous vinyl copolymer of CX ₂ = CY ₂ Vacuum ultraviolet (VUV) to indicate (A / μm) ≤ 1 Provide people substance.

In addition, the present invention provides a monomer ratio of about 1: 2 to about 2: 1 CH ₂ = CHCF ₃ and CF ₂ = CF ₂ , CH ₂ = CFH and CF ₂ = CFCl, CH ₂ = CHF and CClH = CF ₂ ; Perfluoro (2-methylene-4-methyl-1,3-dioxolane) and perfluoro (2,2-dimethyl-1,3-diosol); Amorphous vinyl copolymers of perfluoro (2-methylene-4-methyl-1,3-dioxolane) and vinylidene fluoride in proportions providing an amorphous composition; And a vacuum ultraviolet (VUV) transparent showing absorbance / micron (A / μm) ≦ 1 at 140-186 nm wavelength comprising a homopolymer of perfluoro (2-methylene-4-methyl-1,3-dioxolane) Provide the substance.

The present invention also provides pellicles, antireflective coatings, optically clear glue, light guides and resists comprising the UV transparent materials provided above.

The present invention also provides a copolymer composition comprising poly (hexafluoroisobutylene: trifluoroethylene) having 40-60 mol% hexafluoroisobutylene and 60-40 mol% trifluoroethylene. And poly (hexafluoroisobutylene: vinyl fluoride) having 40-60 mol% hexafluoroisobutylene and 60-40 mol% vinyl fluoride.

The present invention relates to partially fluorinated and fully fluorinated polymers that are substantially transparent to ultraviolet light at wavelengths of about 187 nm to 260 nm.

1 is a graph showing the 157 nm transmittance (unit:%) T of a pellicle as a function of the 157 nm absorbance (unit: inverse of microns) of the polymer in the absorbance range of 0.4 to 0.0 In this calculation, the effect of thin film interference on the pellicle membrane is ignored.

FIG. 2 shows the relationship between absorbance (in reciprocal of microns) versus wavelength lambda (λ) in units of Teflon® AF 1601 (Sample 7a) and Cytop ™ (Sample 13). graph.

FIG. 3 shows refractive index n and extinction coefficient k versus wavelength lambda (unit: nm) of a Teflon® AF 1601 film (Sample 7b) having a thickness of 2146 Hz on a silicon substrate determined by VUV spectroscopic ellipsometry. Graph showing the relationship.

4 is a graph showing the relationship between the spectral transmittance (absolute unit) versus the wavelength lambda (unit: nm) of a pellicle of Teflon® AF 1601 designed as an unsupported tuned etalon with a film thickness of 6059 Hz; . It is clear that the interference fringes of the tuning etalons are a function of the wavelength.

FIG. 5 is a graph showing the relationship between spectral reflectance (absolute units) versus wavelength lambda (units of nm) of a pellicle of Teflon® AF 1601 designed as an unsupported tuning etalon with a film thickness of 6059 Hz. It is clear that the interference fringes of the tuning etalons are a function of the wavelength. The minimum value of pellicle reflectance is observed at 157 nm, which contributes to the maximum pellicle transmission at this lithography wavelength.

FIG. 6 is a graph showing the transmittance of a tuned etalon pellicle film of Teflon® AF 1601 at lithography wavelength 157 nm as a function of pellicle film thickness. Vibration of pellicle transmission with thickness is caused by thin film interference fringes in the film, resulting in pellicle transmission maximum and minimum values. Optimal tuning etalon pellicle designs correspond to films with sufficient mechanical integrity and thickness to maximize transmission. As can be seen, pellicles designed from this material have a substantially lower transmission than the target transmission for the 157 nm pellicle.

7 shows the absorbance (inverse of microns) versus wavelength of Teflon® AF 1200 (sample 8), Teflon® AF 1601 (sample 7a), and Teflon® AF 2400 (sample 5). Graph showing the relationship between lambda (λ) in nm. Note that the absorbance / micron decreases dramatically as all (CF ₂ ) _n chain lengths in the polymer decrease as the PDD content of the polymer increases and the TFE content of the polymer decreases from 52% to 32% again.

FIG. 8 is a graph showing the relationship between absorbance (unit: inverse of microns) versus wavelength lambda (λ) of TFE: HFP (sample 14) and TrFE: HFP (sample 12). The presence of HF carbon in the CF ₂ = CFH monomer interrupts the extended CF ₂ chain. It can also be understood that this effect is due to the fact that the maximum absorbance of the TFE: HFP polymer shifts to shorter wavelengths in the TrFE: HFP polymer.

FIG. 9 shows the absorbance (inverse of microns) versus wavelength lambda (λ) of VF ₂ : PDD (sample 2), VF ₂ : HFP (sample 1), HFIB: TrFE (sample 3) and HFIB: VF (sample 4). ) Is a graph showing the relationship of (nm).

FIG. 10 is a graph showing the relationship between refractive index n and extinction coefficient k versus wavelength lambda (λ) (unit: nm) of a HFIB: VF film (sample 4a) having a thickness of 14,386 Hz on a silicon substrate determined by VUV spectroscopic ellipsomitri.

FIG. 11 is a graph showing the relationship of spectral transmittance (absolute units) to wavelength lambda (λ) in units of HFIB: VF pellicle designed as unsupported tuned etalon with a film thickness of 3660 Hz. It can be seen that the interference fringes of the tuning etalons are clearly a function of the wavelength.

12 is a graph showing the relationship of spectral reflectance (absolute units) to wavelength lambda (λ) in units of HFIB: VF pellicle designed as unsupported tuning etalon with a film thickness of 3660 Hz. It can be seen that the interference fringes of the tuning etalons are clearly a function of the wavelength. The minimum value of pellicle reflectance is observed at 157 nm, which contributes to the maximum pellicle transmission at this lithography wavelength.

FIG. 13 is a graph showing the transmittance of a tuned etalon pellicle film of HFIB: VF having an absorbance / micron of 0.022 and a refractive index of 1.5 at 157 nm lithography wavelength as a function of pellicle film thickness. When the pellicle film thickness is 3660 GPa or less, the maximum pellicle transmittance is higher than the target transmittance 98%.

FIG. 14 is a graph showing the transmittance of a tuned etalon pellicle film of polymer with absorbance / micron 0.01 and refractive index 1.5 at 157 nm lithography wavelength as a function of pellicle film thickness. When the pellicle film thickness was 8371 mm 3, the maximum pellicle transmittance was higher than the target transmittance 98%.

15 shows 5: 6 TFP: TFE (sample 17), HFIB: VF (sample 18), 5: 2 VF2: PFMVE (sample 19), 7: 5 VF2: PFPVE (sample 21) and 79:21 VF2: HFP A graph showing the relationship between absorbance (inverse of microns) versus wavelength lambda (λ) in (Sample 22).

FIG. 16 shows 1: 1 PDD: TrFE (Sample 9), 13:10 VF2: PFMVE (Sample 20), 2: 5: 2 HFP: PFMVE: VF2 (Sample 23), 10: 7 HFIB: VF (Sample 24) And a graph showing the relationship of absorbance (unit: inverse of microns) to wavelength lambda (λ) in units of 6: 5 PDD: PFMVE (sample 25).

FIG. 17 shows 20:11 VF: ClDFE (Sample 26), 1: 2 PDD: VF2 (Sample 27), 1: 1 HFIB: VA (Sample 32), PMD (Sample 33) and PMD: PDD (Sample 34). Graph showing the relationship between absorbance (inverse of microns) versus wavelength lambda (λ).

18: 1: 1 CTFE: VF (sample 6b), 5: 2 VF2: TrFE (sample 10), 10:23 PDD: CTFE (sample 11), 5: 4 VF2: CTFE (sample 15) and 1: 1 Graph showing the relationship between absorbance (unit: inverse of microns) of PMD: TFE (sample 18) versus wavelength lambda (λ) (nm).

19 shows the relationship between absorbance (unit: inverse of microns) versus wavelength lambda (λ) in units of 5: 8 PDD: VF2 (sample 29) and 41:37:22 HFIB: VF: VF2 (sample 19). Graph representing.

The present invention provides fluoropolymer compositions and their use in certain electronic applications.

Some abbreviations used throughout the specification are defined as follows:

TFE tetrafluoroethylene

HFP hexafluoropropylene

VF Vinyl Fluoride

CTFEchlorotrifluoroethylene

VF vinylidene fluoride

HFIB Hexafluoroisobutylene

TrFEtrifluoroethylene

PDD4,5-difluoro-2,2-bis (trifluoromethyl) -1,3-dioxol

PMD perfluoro (2-methylene-4-methyl-1,3-dioxolane)

Teflon® AF 240089: 11 PDD: TFE

Teflon (registered trademark) AF 160168: 32 PDD: TFE

Teflon (registered trademark) AF 120048: 52 PDD: TFE

ClDFE1-chloro-2,2-difluoroethylene

PPVE Perfluoro (propyl vinyl ether)

PMVE Perfluoro (Methyl Vinyl Ether)

VOAc vinyl acetate

VOH vinyl alcohol

TrP3,3,3-trifluoropropene

Fluorinert® FC-75 Fluid for electronics (manufactured by 3M), believed to be similar to perfluoro (butyl tetrahydrofuran).

Fluorinut® FC-40 Electronic fluid (manufactured by 3M), believed to be similar to perfluoro (tributylamine).

Vazo® 56 WSP initiator (manufactured by DuPont)

2,2'-bis (2-amidino-propane) dihydrochloride

DSC Differential Scanning Calorimeter

The use of 157 nm light in next-generation lithography poses a new photochemical problem that has not been encountered in long wavelength lithography. The energy of 157 nm photons (182 kcal / mole or 7.9 eV photons) is so large that ordinary chemical bonds such as CF (108-116 kcal / mole), CH (98-105 kcal / mole), CC (88 -97 kcal / mole) and C-Cl (82-86 kcal / mole) bonds can be broken. The maximum absorbances of the selected hydrocarbons and fluorocarbon compounds are shown in Table 1.

Comparison of maximum UV absorbance of hydrocarbons and fluorocarbons Absorbance wavelength C _n H _{2n + 2} ¹ C _n F _{2n + 2} n = 1 143 nm and 128 nm n = 2 158 nm and 132 nm n = 3 159 nm and 140 nm 119 nm ¹ n = 4 160 nm and 141 nm 126 nm ¹ n = 5 161 nm and 142 nm 135 nm ¹ n = 6 162 nm and 143 nm 142 nm ¹ n = 7 163 nm and 143 nm n = 8 163 nm and 142 nm n = 172 161 nm ^{2 1} B.A. Lombos et al. , Chem. Of BA Lombos, P. Sauvageau and C. Sandorfy . Phys. Lett. , 1967,42] ² K. Seki et al., K. Seki, H. Tanaka, T. Ohta, Y. Aoki, A. Imamura, H. Fujimoto, H. Yamamoto, H. Inokuchi, Phys. Scripta, 41,167 (1990)]

As can be seen from the table, the maximum UV absorbance for both hydrocarbons and fluorocarbons shifts towards longer wavelengths as the chain length increases. The fluorocarbon chain (CF ₂ ) _n absorbs at 157 nm between approximately n = 6 (142 nm) and n = 172 (161 nm), while the hydrocarbon chain (CH ₂ ) _n is initially in the order of n = 2 Absorb at 157 nm. Thus, it is clear that fluorocarbon chains have greater resistance to UV absorption than hydrocarbon chains, and it is not surprising that the industry is gradually moving towards perfluorination when exploring high UV transmittance. However, polymers that are completely transparent at 157 nm and slightly longer wavelengths appear to be excluded, as long as the chain length that provides acceptable transparency can never exceed (CH ₂ ) ₁ or (CF ₂ ) ₆ . Consistent with this, eg, V. yen. VN Vasilets et al ., J. Poly. Sci, Part A, Poly. Chem. , 36, 2215 (1998)] show that poly (tetrafluoroethylene / hexafluoropropylene) [poly (TFE / HFP)] (Teflon® AF FEP) exhibits strong absorption and photochemical degradation at 147 nm. report. Likewise, we have found that 1: 1 poly (hexafluoropropylene: tetrafluoroethylene) absorbs much at 157 nm (Table 2, A / micron = 3.6 @ 157 nm).

Polymers play a decisive role in many areas of lithography: one is a polymer pellicle that is placed on a mask pattern so that no particulate contaminants touch the photomask object plane, making the lithographic image surely flawless. The pellicle is a free-standing polymer membrane, typically 0.8 μm thick, placed in a 5 in ² frame. The pellicle film should have high transparency or light transmittance at the lithography wavelength for efficient image formation, and should not darken or burst with prolonged illumination in the optical stepper. The pellicles for current lithography wavelengths use pellicles with> 99% transmission by using polymers with very low optical absorption combined with thin film interference effects. Sematech's goal for pellicles for use in 157 nm photolithography is greater than 98% transparency for an exposure lifetime of 7.5 m laser pulses of 0.1 mJ / cm 2 of 157 nm light or 7.5 kJ radiation dose.

A pellicle transmittance of 98% corresponds to an absorbance A of about 0.01 per film thickness (μm). Absorbance is defined by Equation 1, where absorbance A per film thickness (microns) is calculated by dividing the log value (log ₁₀ ) of the ratio of the substrate's transmittance divided by the transmittance of the sample consisting of a sample of polymer film on the substrate (log ₁₀ ) Is defined.

In this way, the unit of absorbance A is the inverse of micron (or 1 / micron), where micron is the micrometer (or μm) of the polymer film thickness. The absorbance / micron of the polymer film discussed herein was measured for a polymer film spin coated onto a CaF ₂ substrate using standard methods. The VUV transmittance of each CaF ₂ substrate is measured before spin coating the polymer film. The VUV transmittance of the polymer film on the particular CaF ₂ substrate was then measured, and the absorbance / micron value of the polymer was determined as a function of wavelength using the measured film thickness (reported in Table 2) and Equation 1 Absorbance / micron values at 157 nm, 193 nm and 248 nm are shown in Table 2. For some materials two films of different thicknesses are shown in Table 2 and the absorbance / micron values of each film are also presented.

The VUV transmittances of the CaF ₂ substrate and the polymer film on the CaF ₂ substrate were measured with a laser plasma light source, a sample chamber capable of measuring both transmittance and reflectance, a 1 m monochromator, and a 1024 element photo coated with sodium salicylate phosphor. Measurements were made using a VUV spectrophotometer using a diode detector. This is R. H. In more detail in RH French, "Laser-Plasma Sourced, Temperature Dependent VUV Spectrophotometer Using Dispersive Analysis", Physica Scripta , 41,4,404-8 (1990), which is incorporated herein by reference. Are discussed.

The absorbance / micron of the polymer will determine the average transmittance of the unsupported pellicle film made from that polymer. FIG. 1 shows the 157 nm transmittance T of the pellicle in% as a function of the 157 nm absorbance of the polymer (inverse of microns) for the absorbance range 0.4 to 0.0. This calculation ignores the influence of thin film interference on the pellicle membrane. Results are shown for pellicle films ranging from 0.2 micron to 1 micron in thickness, demonstrating that pellicle transmission can be increased by using thinner pellicle film thickness for any particular polymer. Since the pellicle film is an unsupported polymer membrane and must have sufficient mechanical strength and integrity, this approach of increasing pellicle transmission has a limited range of applications. This mechanical requirement suggests the use of a polymer having a relatively high glass transition temperature T _g and a polymer film thickness of at least 0.6 microns. It can be seen from FIG. 1 that the target absorbance / micron of the polymer for pellicle application is <0.02 absorbance / micron at 157 nm.

2 shows the relationship between absorbance (in reciprocal of microns) versus wavelength lambda (λ) in units of Teflon® AF 1601 and Cytop ™. At 157 nm, the absorbance / micron value of the cytope is 1.9 / micron, while the absorbance of Teflon® AF 1601 is 0.42 / micron, about five times smaller than the cytope. Example 1 demonstrates that even the 157 nm absorbance of Teflon® AF 1601 of 0.42 / micron is so high that it cannot be used as a pellicle for use at 157 nm.

In the wavelength range of 186-800 nm corresponding to the energy range of 1.5-6.65 eV, with VUV ellipsomite (VASE) measurements performed at one angle of incidence from 143-275 nm corresponding to an energy range of 4.5-8.67 eV. Optical properties (refractive index "n" and extinction coefficient "k") are determined from variable angle spectroscopic ellipsometry (VASE) (ie from VUV-VASE) at three angles of incidence. The polymer film is spin coated onto a silicon substrate. VASE ellipsometer is J.A. Manufactured by J.A. Woollam Company (645 M Street, Suite 102, Lincoln, NE 68508 USA). Optical constants are fitted to these data simultaneously using an optical model of the film on the substrate. O.S. Heavens, Optical Properties of Thin Solid Films, pp. 55-62, Dover, NY, 1991. This document is incorporated herein by reference.

From understanding the spectral dependence of the optical properties, the transmittance of a pellicle film of any thickness can be calculated by using an optical model of an unsupported pellicle film of a particular polymer film thickness and calculating the pellicle film transmittance and reflectance. In this manner, the pellicle film thickness can be optimized to exhibit a thin film interference maximum at the desired lithography wavelength in the pellicle transmission spectrum. This transmittance maximum is determined from the refractive index of the polymer, the lithographic wavelength of interest and the film thickness and occurs for various film thicknesses. The transmittance maximum of a suitably tuned etalon pellicle film occurs where the reflectivity of the pellicle film exhibits a minimum value and corresponds to minimizing pellicle reflectance and maximizing pellicle transmission at the lithographic wavelength. The relationship between the extinction coefficient k, the extinction coefficient α, and the absorbance / micron A is shown in the following equation (2), where? This relationship is useful for comparing the results of absorbance measurements and ellipsomite measurements. This relationship to A is exactly correct if light scattering in the polymer film (which can occur due to the crystallinity of the polymer), thin film interference effects and surface scattering effects are minimized.

Polymeric materials with very low absorbance / micron or extinction coefficients and low refractive index values also have very important applications as antireflective coatings and optical adhesives. As taught herein, materials with low absorbance can be used to reduce light reflected from the surface of a transparent substrate having a relatively high refractive index. This reduction in reflected light is accompanied by an increase in light transmitted through the transparent substrate material. The antireflective coating effect of these low absorbance / micron materials is the result for VF ₂ : PDD, VF ₂ : HFP, HFIB: TrFE and HFIB: VF (where, for very thin films, the absorbance of the polymer on the CaF ₂ substrate is negative). -) Absorbance / micron). This corresponds to that increased as compared to the light transmittance through the CaF ₂ substrate without 157 nm light transmission through the polymer film on the substrate CaF ₂ on the polymeric film. For VF ₂ : HFP, HFIB: TrFE and HFIB: VF, we measured a much thicker polymer film (which is also shown in Table 2) where no antireflective coating effect was observed, in which case the absorbance / micron of the polymer It can be seen that it is positive and very small.

These polymers can be used as adhesives to bond optical elements together, and because they have low optical absorbance / micron and low refractive index values, they serve to reduce light reflectance at the air / substrate interface among optical elements and transmit The greater amount of light directed serves to direct from one optical element of the system to the next.

The materials of the present invention are useful in the manufacture of transmissive optical devices such as lenses and beam splitters for use in the vacuum UV region.

In addition, these materials can be used as elements of a composite lens intended to reduce chromatic aberration. Currently, only CaF ₂ and possibly hydroxyl-free silica appear to have transparency at 157 nm sufficient to be used in permeable focusing devices. It is also well known that sagittal lenses can be formed by using second materials having different refractive indices and dispersions (eg, R. Kingslake, Academic Press, Inc., 1978, Lens Design Fundamentals, p. 77). The Selmeier fit for the data shown in FIG. 10 for HFIB: VF as described in Example 4 shows that it has a refractive index of 1.4942 and dispersion of 0.00220 nm ⁻¹ at 157 nm. Edward D. Similar fits to the refractive index data of CaF ₂ from Edward D. Palik, Handbook of Optical Constants of Solids II, p.831, Academic Press, Inc., Boston, MA (1991) and French. It shows that it has refractive index 1.5584 and dispersion degree 0.00234 nm ⁻¹ at 157 nm. Therefore, it is expected that by using one of these materials with CaF ₂ , a saximation lens can be made from this material and other similar materials described herein.

A further field in which polymers play a decisive role is in the field of photosensitive photoresists that capture optical latent images. In the case of a photoresist the light must pass through the entire thickness of the resist layer for the optical latent image, and during the optical phase formation a well defined vertical sidewall will be formed, which will produce the desired resist image for the developed polymer. When used as a resist at 157 nm, if the resist thickness is limited to about 2000 GPa, the polymer can have a fairly high extinction coefficient A <about 2-3 per film thickness (μm).

WO9836324 describes carbon / fluoro polymers such as poly (tetrafluoroethylene / hexafluoropropylene) as pellicle membranes having absorbance A / μ of 0.1 to 1 for use at 140-200 nm. Vasilets's report on high absorbance and photolysis of poly (hexafluoropropylene / tetrafluoroethylene) at 148 nm [VNVasilets, et al, J. Poly. Sci., Part A, Poly. Chem. , 36, 2215 (1998), which combines the data of Table 1 above and the data of Applicants' data with additional literature data, question the disclosure of WO 9836324. For example, it can be seen that poly (tetrafluoroethylene: hexafluoropropylene), i.e., polymer 14 in Table 2, has a relatively strong absorbance at 157 nm, A / μ = 3.9, Failure to meet the target (A / μ <0.01) as well as the industry target for looser resists (A / μ <2-3). Japanese Patent No. 072952076 claims a bilayer membrane of Cytop ™ and Teflon® AF 1600 as a pellicle film. At 157 nm, the A / μ of Cytop ™ is 1.9 (Polymer 13 in Table 2) and the A / μ of Teflon® AF 1600 is 0.4 (Polymer 7 in Table 2). This is not surprising given the data in Table 1, which shows that significant VU light absorption occurs at 160 nm whenever there are more than about 6 CF ₂ groups in a chain. In fact, W. H. WHBuck and P. Egg. PR Resnick reports that more than 30% of its CF ₂ units are present as (CH ₂ ) _n chains with n> 6, consistent with Teflon® AF 1600 of A / μ = 0.4. J. Schirs, Modern Fluoropolymers, John Wiley, New York, 1997, Chapter 22, page 40. If the interactions responsible for this absorbance cannot be disrupted, it would seem impossible to find that the carbon-based polymer is completely transparent at wavelengths shorter than about 160 nm.

Table 2 below shows the absorbance / micrometer (A / μ) at 157 nm of partially coated and fully fluorinated polymer films on CaF ₂ crystals. The polymers are described in order of increasing absorbance. In some cases, more than one sample of several polymers was prepared in one example. Thus, the table is identified by both the example number (first column) and the sample number. In addition, references to figures showing the spectra of various polymers are referenced back and forth in the table.

(A / µm) is determined from absorbance measurements based on VUV transmittance. One result marked with # was determined by VUV ellipsomite.

^1, J. Scheirs, editor, Modern Fluoroplastics, John Wiley U Sons, West Sussex, England, 1997, Chapter 28]

² PDD = 4,5-difluoro-2,2-bis (trifluoromethyl) -1,3-diosol

³ PMD = perfluoro (2-methylene-4-methyl) -1,3-dioxolane

⁴ Teflon® AF 2400

⁵ Teflon® AF 1601

⁶ Teflon® AF 1200

⁷ monomers included in molar ratio 3: 4. Polymer product not analyzed.

Three of the bicyclic polymer structures listed in Table 2 show no UV absorption that can be detected at 157 nm (polymers VF ₂ : HFP, HFIB: TrFE and HFIB: VF). These are copolymers containing vinylidene fluoride (VF ₂ ) or hexafluoroisobutylene (HFIB). VF ₂ and HFIB have unique structural features in common. In view of that, for example, hexafluoroisobutylene monomers cannot form CH ₂ chains longer than CH ₂ CH ₂ before the chains are broken by —C (CF ₃ ) ₂ — segments. Likewise, vinylidene fluorides cannot form CH ₂ chains longer than CH ₂ CH ₂ before they are broken by CF ₂ or form longer CF ₂ chains than CF ₂ CF ₂ before they are broken by CH ₂ Can not. That is, CX ₂ = CY ₂ monomers, such as VF ₂ and HFIB, have a “self-interrupting” property when determining the potential for extended interactions between CF bonds or extended interactions between CH bonds. The rigid five-membered ring of PDD will probably have an associated effect by forcing a form that is detrimental to interaction. Comparing the PDD / TFE copolymers 5, 7 and 8, the absorbance decreases from 0.6 to 0.4 back to 0.0 as the TFE content is reduced from 52 mol% to 32 mol% again. That is, transparency is improved because the increasing PDD content interrupts the (CF ₂ ) _n chain. It is anticipated that other perfluorinated ring structures or partially fluorinated ring structures may also be found that function identically to PDD.

A solution of TFE: HFP and a solution of TrFE: HFP were spincoated on a CaF ₂ substrate at a spin rate of 6000 rpm to produce polymer films 1850 kPa and 1389 kPa, respectively. The absorbance / micron is then determined using the VUV absorbance measurement.

The introduction of TrFE instead of TFE represents another example of reducing 157 nm absorbance / micron. The relationship between absorbance (in reciprocal microns) versus wavelength lambda (λ) in TFE: HFP and TrFE: HFP is shown in FIG. 8. The presence of CHF carbon in the CF ₂ = CFH monomer interrupts the extended CF ₂ chain.

This reduces the 157 nm absorbance of 3.9 / micron TFE: HFP to 1.37 / micron TrFE: HFP absorbance / micron. This effect can also be understood as the maximum absorbance of the TFE: HFP polymer shifts to shorter wavelengths in the TrFE: HFP polymer.

Accordingly, we have found that PDD and CX ₂ = CY ₂ monomers (X = F or CF ₃ and Y = H) and optionally other monomers necessary to introduce solubility or destroy crystallinity CR ^a R ^b = CR ^c R ^d Wherein any one or both of R ^a , R ^b or R ^c is H or F, and R ^d is F, CF ₃ , ORf, where Rf is C _n F _{2n + 1} and n is 1 to 3 ) And a high transparency (A / μ <1, more preferably A / μ <0.1) polymer class for <186 nm light prepared by homopolymerizing or copolymerizing OH (when R ^c = H)) do. When a CR ^a R ^b = CR ^c R ^d monomer randomly polymerizes with a PDD or CX ₂ = CY ₂ monomer, it cannot be present in an amount greater than about 25 mole percent, because at higher concentrations statistics are noted. This is because it starts to accept a chain long enough CR ^a R ^b = CR ^c R ^d for good absorption. As mentioned above, this is a PDD: TFE copolymer (polymers in Table 2, respectively, with A / μ dropping from 0.6 to 0.4 back to 0.0 as the TFE content decreased from about 52 mol% to 32 mol% back to 11 mol%). Teflon (registered trademark) AF 1200, Teflon (registered trademark) AF 1601, and Teflon (registered trademark) AF 2400). ^{CR a R b = CR c R} d may be the PDD monomer or CX ₂ = CY ₂ monomers and the higher concentration of ^{CR a R b = CR c R} d monomers when polymerized in an alternating manner allows. An example of this is a 1: 1 HFIB: TrFE copolymer (Table 2, Polymer 3) with A / μ of −0.05. Of course, random and alternating structures are by no means 100% ideal, and some monomers inherently tend to block or avoid polymerization with themselves, such that 25% CR ^a R ^b = CR ^c R ^d and alternating structures for random structures. The limit of 50% CR ^a R ^b = CR ^c R ^{d for} is approximate. And a second copolymer: other combinations transparency is high is _{CH 2 = CHCF 3: CF 2} = CF 2, CH 2 = CHF: CF 2 = CFCl, CH 2 = CHF: CClH = CF 2 2 : 1 to 1 . Preferred monomers of CX ₂ = CY ₂ include vinylidene fluoride and hexafluoroisobutylene. Preferred CR ^a R ^b = CR ^c R ^d monomers introduce an asymmetric center into the polymer chain such as vinyl fluoride, trifluoroethylene, hexafluoropropylene and chlorotrifluoroethylene to increase solubility and destroy crystallinity. Things. Finally, it should be pointed out that forming a highly transparent structure as defined above does not automatically form a polymer useful for all applications. For example, the crystallinity of poly (vinylidene fluoride) precludes its use as a completely clear and transparent optical material [ie. It is already pointed out that the inability to use poly (vinylidene fluoride) as a pellicle may be due to physical reasons (light scattering), not due to absorbance. As another example, poly (perfluorodimethyldioxoles) are so insoluble that they cannot be easily spincoated into thick films. In the case of poly (perfluorodimethyldioxoles) this can be achieved by coating the liquid monomer and polymerizing in situ. Films thicker than about 250 nm can be prepared by placing monomers (optionally diluted with a solvent and / or initiator) in the position where the film is to be formed. The polymerization can be initiated by any suitable physical and / or chemical means, such that the polymer is attached to the desired position as it is formed. The result obtained after removal of the solvent is then a thicker polymer film than can be produced by conventional solvent coating techniques. As a last example, poly [vinylidene fluoride / perfluoro (methyl vinyl ether)] is a tacky rubber useful for glues but not as a self-supporting pellicle film. As used herein, the term amorphous fluoropolymer means a fluoropolymer that does not exhibit a melting point when analyzed by differential scanning calorimetry. No melting point means no melting point associated with thermal events greater than 1 J / g.

Listing a monomer as a precursor of a transparent polymer does not imply that it homopolymerizes or forms a copolymer with any other monomer listed. For example, hexafluoroisobutylene does not form a useful amount of homopolymer with a certain level of molecular weight or does not copolymerize with tetrafluoroethylene under normal conditions. These materials claim to be used at 140 nm-186 nm, but they also produce excellently clear polymers at longer wavelengths up to 800 nm and may also be suitable for some applications at much shorter wavelengths. Particularly preferred wavelengths are 140-160 nm, more preferably 150-160 nm and most preferred wavelengths are 155-159 nm.

Many of the test polymers were obtained with commercial samples:

Teflon (registered trademark) AF 1200: DuPont (Wilmington, Delaware, USA)

Teflon® AF 1600: DuPont

Teflon® AF 2400: DuPont

Cytop ™: Poly [perfluoro (butenylvinylether)], Asahi Glass

About 1: 1 poly (hexafluoropropylene: tetrafluoroethylene) was prepared by the procedure described in US Pat. No. 5,478,905 (December 26, 1995).

Many of the remaining polymer compositions are known in the art and prepared by standard methods. Typically, a monomer, a solvent, and an initiator were added to an autoclave and heated to initiate polymerization. Most polymerization was initiated using hexafluoropropylene oxide dimer peroxide 1 (DP) at ambient temperature:

CF ₃ CF ₂ CF ₂ OCF (CF ₃ ) (C = O) OO (C = O) CF (CF ₃ ) OCF ₂ CF ₂ CF ₃

1, DP

Prepare DP and solution from 0.05 to 0.2M in solvent such as Vertrel ™ XF (CF ₃ CFHCFHCF ₂ CF ₃ ) or 3M Performance Fluid PF-5080 (close to perfluorooctane) Used as. DP is conveniently used for routine laboratory procedures [Chengue, et al., J. Org. Chem. , 47,2009 (1982) or, if required, by a jet mixer method (US Pat. No. 5,962,746; registered October 5, 1995). The reaction mixture was then recovered and the polymer was isolated by evaporation or filtration. Polymer composition was determined by elemental analysis or NMR. For the new material composition a process was provided for preparation, and for a known composition a representative process was provided.

The polymer film was prepared by spin coating a polymer solution on a CaF ₂ substrate, followed by post apply bake of the polymer film on the substrate sample to leave no residual solvent in the polymer film. The post-coating baking temperature was 120-250 ° C. for 2-5 minutes on a hot plate or overnight in a vacuum oven. The spin rates of the samples are listed in Table 2.

Polymer film thicknesses can be determined using single or multiple wavelength ellipsomitri, discussed below, or by the Filmmetrics Model F20 thin film measurement system (Filmetrics, Inc .; United States 92111-2255 San Diego Suites, California). 140 Dagger Street 7675). Film thicknesses are reported in Table 2. For some materials, two films of different thicknesses are presented in the table, and the absorbance / micron values are presented for each film.

Comparative Example A: Teflon (registered trademark) AF 1601

A solution of Teflon® AF 1601 was spin coated onto a CaF ₂ substrate at a spin speed of 6000 rpm to prepare a polymer film having a thickness of 3323 mm 3. Absorbance / micron was then determined using VUV absorbance measurements.

Teflon® AF 1601 is a 68:32 PDD: TFE polymer, which is currently used as a polymer for pellicles designed for use in lithography wavelengths of 248 nm and 193 nm. The absorbance / micron for 157 nm light was 0.42 / micron as determined by VUV absorbance measurements. 1, this corresponds to a pellicle transmittance of 70% or less of a pellicle film having a thickness of only 0.2 microns, and of course, this result does not take into account the additional effect of the thin film interference effect resulting from a properly designed pellicle film. .

To determine the VUV optical properties of Teflon® AF 1601, VUV ellipsomitri was performed on a Teflon® AF 1601 polymer sample on a silicon wafer and the refractive index and extinction coefficient shown in FIG. 3 were determined. The 157 nm refractive index of Teflon® AF 1601 was 1.4251. The determined 157 nm extinction coefficient corresponds to the absorbance / micron of 0.35 / micron, which is also listed in Table 2.

Optical properties of these Teflon® AF 1601 and the O. S. discussed above. Using the methods of Heavens, O.S. Heavens, it is possible to design tuned etalon pellicle films in which the reflectance of the unsupported pellicle film is minimized and the pellicle transmission is maximized. (Etalons are thin films in which the effects of thin film interference, such as constructive and destructive interferences of light from the front and back of a certain thickness film, produce optical fringes whose wavelength reflects or transmittances of thin films (Principles of Optics, a book by Max Born and Emil Wolf, Pergamon Press, New York, 6th Edition, copyright 1980, pp 329-333) .When the pellicle film thickness is 6059 Hz, the 157 nm pellicle transmittance is 65.7%, while the 157 nm pellicle reflectance is The relationship between the spectral transmittance (absolute unit) versus the wavelength lambda (λ) of the pellicle of Teflon® AF 1601 designed with unsupported tuned etalon with a film thickness of 6059 mm 3 in Fig. 4. It is clear that the interference fringe of the tuning etalon is a function of the wavelength Spectroscopy of the pellicle of Teflon® AF 1601 designed with unsupported tuning etalon with a film thickness of 6059 Hz in Fig. 5. The relationship between the modulus (absolute units) versus the wavelength lambda (λ) is apparent: It can be clearly seen that the interference fringes of the tuning etalons are a function of the wavelength and the minimum value of the pellicle reflectance is observed at 157 nm. Contributes to the maximized pellicle transmission at this lithography wavelength.For a 157 nm pellicle film of Teflon® AF 1601 with a film thickness of 6335 kPa, the tuning etalon will not be optimized for maximum pellicle transmission, 157 nm The pellicle transmission will be 59.4%, while the 157 nm pellicle reflectivity will increase to 8.1%.

The transmittance of the tuned etalon pellicle film of Teflon® AF 1601 at 157 nm lithography wavelength is shown in FIG. 6 as a function of pellicle film thickness. Vibration of pellicle transmittance with thickness occurs because of thin film interference fringes in the film, resulting in pellicle transmittance maximum and minimum values. Optimal tuning etalon pellicle designs correspond to films with sufficient mechanical integrity, and thickness such that transmittance is at its maximum. As can be seen, pellicles designed from this material have a transmittance substantially lower than the target transmittance of 98% of the 157 nm pellicle.

The pellicles designed from Teflon® AF 1601 cannot achieve pellicle transmission above 98%. A pellicle designed from Cytop ™ with a much higher 157 nm absorbance / micron will have a much lower 157 nm pellicle transmission. This demonstrates the need for a method of making a polymer with a dramatically lower 157 nm absorbance / micron to meet the desired 98% 157 nm transmission of the pellicle film. Thus, there is a need for polymers having substantially lower absorbance / microns.

Example 1-PDD / TFE

Solutions of Teflon® AF 1200, 1601 and 2400 were spin-coated on a CaF ₂ substrate at a spin rate of 6000 rpm to produce polymer films of 4066 kV, 3323 kV and 2133 kV, respectively. Absorbance / micron was then determined using VUV absorbance measurements.

FIG. 7 shows the relationship between absorbance (unit: inverse of microns) versus wavelength lambda (λ) in units of Teflon® AF 1200 as Sample 8. The 157 nm absorbance / micron was determined to be 0.64 / micron. The 193 nm absorbance / micron was determined to be 0.004 / micron. The 248 nm absorbance / micron was determined to be -0.001 / micron.

FIG. 7 shows the relationship between absorbance (unit: inverse of micron) versus wavelength lambda (λ) in units of nm of Teflon® AF 1601 as Sample 7a. The 157 nm absorbance / micron was determined to be 0.42 / micron. The 193 nm absorbance / micron was determined to be 0.02 / micron. The 248 nm absorbance / micron was determined to be 0.01 / micron.

FIG. 7 shows the relationship between absorbance (unit: inverse of microns) versus wavelength lambda (λ) in units of Teflon® AF 2400 as Sample 5. The 157 nm absorbance / micron was determined to be 0.007 / micron. The 193 nm absorbance / micron was determined to be -0.06 / micron. The 248 nm absorbance / micron was determined to be -0.06 / micron.

One way to dramatically reduce the 157 nm absorbance of PDD: TFE polymers is to increase the PDD fraction in the polymer. In judging the potential of extended interactions between CF bonds by forcing a disadvantaged form, the rigid five-membered ring of PDD will probably have a similar effect of "self-interrupted" like VF ₂ and HFIB. This is shown in FIG. 7 where the absorbances (inverse of microns) versus wavelength lambda (λ) of Teflon® AF 1200, Teflon® AF 1601 and Teflon® AF 2400 ) Demonstrates that the 157 nm absorbance / micron of these polymers is reduced. Comparing the PDD / TFE copolymer Teflon® AF 1200, 1601 and 2400, the 157 nm absorbance / micron was 0.4 at 0.6 / micron as the TFE content dropped from 52 mol% to 32 mol% back to 11 mol%. Fall back to 0.01 microns / micron. That is, transparency is improved because the increasing PDD content interrupts the (CF ₂ ) n chain. It is expected that other perfluorinated ring structures or partially fluorinated ring structures can be found that function the same as the PDD.

Example 2-HFIB / TrFE

Preparation of 1: 1 Poly (hexafluoroisobutylene: trifluoroethylene)

In a 75 ml stainless steel autoclave cooled to <-20 ° C., 25 ml of CCl ₂ FCF ₂ Cl and 5 ml of about 0.17 M DP in Bettrel ™ XF were added. The autoclave was cooled, evacuated, and further 10 g of trifluoroethylene and 20 g of hexafluoroisobutylene were added. The reaction mixture was shaken overnight at ambient temperature (28-33 ° C.), removed from the autoclave, evaporated to a glassy film and further dried in a 75 ° C. vacuum oven for 72 hours. 3.33 g of a white solid were obtained. A solution was prepared by rolling 3.24 g of this polymer with 6.99 g of 1-methoxy-2-propanol acetate (PGMEA). The solution was mixed with 0.2 g of chromatographic silica gel and 0.2 g of decolorized carbon, first passed through a 0.45 μ glass microfiber syringe filter (Whatman, Autovial ™) and then 0.45 μ PTFE Passed through a membrane syringe filter (Whatman, Autovial ™). The fluorine NMR of this solution is about 1: 1 by integrating CHF fluorine of trifluoroethylene at about -180 to -220 ppm relative to CF ₃ fluorine of hexafluoroisobutylene at about -58 to -65 ppm. It was found to be hexafluoroisobutylene: trifluoroethylene. This solution was used to spin coat a thick film on an optical substrate for absorbance measurements.

Sample Preparation and Results:

The HFIB: TrFE solution was spin coated onto a CaF ₂ substrate at spin speeds of 3000 rpm and 6000 rpm to produce polymer films of 12146 mm3 and 1500 mm3, respectively. Absorbance / micron was then determined using VUV absorbance measurement.

The absorbance (inverse of microns) versus wavelength lambda (λ) in units of 3: 2 HFIB: TrFE is shown as sample 3a in FIG. 9. The 157 nm absorbance / micron determined from the thicker polymer film was 0.012 / micron. 193 nm absorbance / micron was determined to be 0.005 / micron. 248 nm absorbance / micron was determined to be -0.001 / micron.

Example 3-HFIB / VF

Preparation of 3: 2 poly (hexafluoroisobutylene: vinyl fluoride)

In a 75 ml stainless steel autoclave cooled to <-20 ° C., 25 ml of CCl ₂ FCF ₂ Cl and 10 ml of about 0.07 M DP in Bettrel ™ XF were charged. The autoclave was cooled, evacuated, and further 16 g of hexafluoroisobutylene and 5 g of vinyl fluoride were added. The reaction mixture was shaken at ambient temperature (18-26 ° C.) overnight, removed as a thick gel from the autoclave, evaporated and further pumped for 96 hours with a vacuum pump, then dried in a 75 ° C. vacuum oven for 22 hours. I was. Tg was 58 ° C. (nitrogen, 10 ° C./min, secondary heating) and Tm yielded 19 g of an undetectable brittle white solid.

Theoretical value of (HFIB) ₃ (VF) ₂ : 32.89% C2.07% H

Found: 32.83% C2.08% H

Solution Preparation and Results:

6 g of this polymer was rolled with 12 g of 2-heptanone to prepare a solution. This solution was passed through a 0.45 μ glass microfiber syringe filter (Watman, Motorcycles ™) and the filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

Sample Preparation and Results:

The HFIB: VF solution was spin coated onto a CaF ₂ substrate at 3000 rpm (rotations per minute) and a spin speed of 6000 rpm to produce polymer films of 14386 mm3 and 2870 mm3, respectively. Absorbance / micron was then determined using VUV absorbance measurement.

The absorbance (inverse of microns) vs. wavelength lambda (λ) in 1: 1 HFIB: VF is shown as sample 4a in FIG. The 157 nm absorbance / micron determined from the thicker polymer film was 0.027 / micron. 193 nm absorbance / micron was determined to be 0.020 / micron. 248 nm absorbance / micron was determined to be 0.008 / micron.

To determine the VUV optical properties of HFIB: VF, VUV ellipsomitri was performed on HFIB: VF polymer samples on silicon wafers to determine refractive index and extinction coefficient as shown in FIG. 10. The 157 nm refractive index of Teflon® AF 1601 was 1.50. The determined 157 nm extinction coefficient corresponds to the absorbance / micron of 0.022 / micron and is also shown in Table 2.

These optical properties of HFIB: VF and the above O.S. Using Heavens' method, a tuned etalon pellicle film can be designed, wherein the reflectance of the unsupported pellicle film is minimal and the pellicle transmission is maximum. For a pellicle film thickness of 3660 mm 3, the 157 nm pellicle transmittance was 98%, while the 157 nm pellicle reflectance was 0.08%. The relationship between the spectral transmittance (absolute unit) versus the wavelength lambda (unit: nm) of a pellicle of HFIB: VF designed as an unsupported tuning etalon with a film thickness of 3660 mm 3 is shown in FIG. 11. It can be clearly seen that the interference fringes of the tuning etalons are a function of the wavelength. The relationship between the spectral reflectance (absolute unit) versus the wavelength lambda (unit: nm) of a pellicle of HFIB: VF designed as an unsupported tuning etalon with a film thickness of 3660 mm 3 is shown in FIG. 12. It can be clearly seen that the interference fringe of the tuning etalon is a function of the wavelength, and a minimum of pellicle reflectance is observed at 157 nm, which contributes to the maximized pellicle transmission at this lithography wavelength. For a 157 nm pellicle film of HFIB: VF with a film thickness of 3660 mm 3, the tuning etalon is a 157 nm pellicle with a 157 nm pellicle transmittance of 98%.

The transmittance of the HFIB: VF tuned etalon pellicle film at the lithography wavelength of 157 nm is shown in FIG. 13 as a function of the pellicle film thickness. Vibration of pellicle transmission with thickness occurs because of the thin film interference fringes of the film, providing pellicle transmission maximums and minimums.

Example 4-VF2 / PDD

Sample Preparation and Results:

25 ml of CF ₂ ClCCl ₂ F was placed in a 75 ml autoclave, precooled to <-20 ° C., and further perkadox 16N [bis (4-t-butylcyclohexyl) peroxydicarbonate] And perfluorodimethyldioxol (PDD) were added and evacuated, and 10.4 g of vinylidene fluoride (VF ₂ ) was added. It heated at 70 degreeC for 18 hours, and obtained thick oil. Evaporated in air, dried for 22 hours under pump vacuum, and dried for 24 hours in a 75 ° C. oven to yield 17 g of a solid white foam.

Elemental Analysis Found: 28.99% C 1.11% H

Theoretical value of (C ₅ F ₈ O ₂ ) ₁ (C ₂ H ₂ F ₂ ) ₁ : 29.05% C 1.08% H

DSC, 10 ° C / min, nitrogen: Tg = 56 ° C (primary heating).

Tg was not detected in secondary heating.

A viscous solution was prepared by rolling 4 g of poly (PDD / VF ₂ ) with 16 g of hexafluorobenzene and filtered through a 0.45 μ glass fiber syringe filter (Watman, Motorcycles ™). The filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

A VF ₂ : PDD solution was spin coated onto a CaF ₂ substrate at a spin speed of 6000 rpm to produce a polymer film with a thickness of 2097 mm 3. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between the absorbance of VF ₂ : PDD (inverse of microns) to wavelength lambda (λ) in nm is shown in Sample 9 in FIG. 9. The 157 nm absorbance / micron determined from the thicker polymer film was -0.04 / micron. In the case of this highly transparent material, this demonstrated an antireflective coating effect, thereby providing a negative value of 157 nm absorbance / micron. 193 nm absorbance / micron was determined to be 0.02 / micron. 248 nm absorbance / micron was determined to be 0.08 / micron.

Example 5-VF2 / HFP

Sample Preparation and Results:

Poly (vinylidene fluoride / hexafluoropropylene) samples were prepared and characterized according to the method of US Pat. No. 4,985,520 (1991.1.15).

Composition by fluorine NMR in deuterium acetone: 21 mol% VF ₂ , 79 mol% HFP

DSC, 10 ° C / min, nitrogen: Tg = -22.5 ° C (secondary heating)

Intrinsic viscosity, acetone, 25 ° C = 0.753 dL / g

The VF ₂ : HFP solution was spin coated onto a CaF ₂ substrate at a spin rate of 3000 rpm and 6000 rpm (rotations per minute) to produce polymer films of 69800 mm 3 and 1641 mm thick. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between absorbance (inverse of microns) versus wavelength lambda (λ) in 79:21 VF ₂ : HFP is shown as sample 1a in FIG. 9. The 157 nm absorbance / micron determined from the thicker polymer film was 0.015 / micron. 193 nm absorbance / micron was determined to be 0.005 / micron. 248 nm absorbance / micron was determined to be 0.003 / micron.

Example 6-VF2 / HFP, VF2 / PDD, HFIB / TrFE pellicle

Using polymers such as VF ₂ : HFP, VF ₂ : PDD, and HFIB: TrFE with 157 nm absorbance / micron on the order of 0.01 / micron, tuning etalon pellicles with high transmittance and substantial film thickness could be designed. In Fig. 14 the transmittance of a tuned etalon pellicle film of polymer with absorbance of 0.01 / micron and refractive index of 1.50 at a lithography wavelength of 157 nm is shown as a function of pellicle film thickness. For a pellicle film thickness of 8371 kPa or less, the maximum pellicle transmittance was greater than the target transmittance 98%.

Example 7-TFE / TrP

A. Polymerization of Tetrafluoroethylene (TFE) and 3,3,3-trifluoropropene (TrP)

20 mL CF ₂ ClCCl ₂ F was placed in a 240 mL autoclave, cooled to <-20 ° C., and 10 mL of about 0.17M DP in CF ₃ CFHCFHCF ₂ CF ₃ was added. The autoclave was further cooled, vented and 10 g TrP and 40 g TFE were added. After shaking overnight at room temperature, the autoclave was evacuated, the fluid reaction mixture was evaporated and finished 48 hours at room temperature under vacuum pump. This gave 9.96 g of a sticky colorless rubbery material.

Elemental analysis found: 29.86% C, 1.74% H

Theoretical value of (C ₃ H ₃ F ₃ ) ₅ (C ₂ H ₄ ) ₆ : 30.02% C, 1.40% H

DSC, 10 ° C / min, nitrogen: Tg = 8.8 ° C (secondary heating)

Solution Preparation and Results:

The solution was prepared by rolling 4 g of poly (TFE / TrP) with 12 g of hexafluorobenzene and filtered through a 0.45 μ glass microfiber syringe filter (Watman, Motorcycles ™). The filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

A 5: 6 TFP: TFE solution was spin coated onto a CaF ₂ substrate to prepare a 41413 mm thick polymer film. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between the absorbance (inverse of microns) and wavelength lambda (λ) in units of 5: 6 TFP: TFE is shown as sample 17 in FIG. 15. 157 nm absorbance / micron was determined to be 0.149 / micron. 193 nm absorbance / micron was determined to be 0.008 / micron. 248 nm absorbance / micron was determined to be -0.00085 / micron.

B. Use as a glue for quartz and aluminum

Aluminum coupons 1 "wide, 3" long, 122 mils thick and quartz slides 1 "wide, 3" long, 65 mils thick were both washed with CF ₂ ClCCl ₂ F and air dried.

4 g of poly (TFE / TrP) prepared above were rolled with 12 g of hexafluorobenzene at room temperature to obtain a clear colorless solution which was passed through a 0.45 μ glass fiber filter. Three drops of this solution were placed on one end of the aluminum coupon, on which the quartz slide was pushed down so that the last inch of the quartz slide overlapped the last inch of the aluminum coupon. This squeezed out excess fluid and wetted the areas where the residual polymer solution overlapped and spread evenly over it. Two C-clamps (stock number 72020, ACCO USA Inc., 60090, Wheeling AC Plaza, Illinois, USA 770-S) were used to hold the aluminum coupon and the quartz slide in place, and hexafluoro for 3 days at room temperature. Benzene solvent was evaporated. One such assembly was heated in a 50 ° C. vacuum oven for 16 hours with the C-clamp still attached. The force required to remove the assembly from the oven, cool, remove the C-clamps, and pull the quartz slide off the aluminum coupon was measured by Instron using a jaw interval of 3 "and a crosshead speed of 1" / min. . 12 pounds of force was needed. The other of these assemblies was heated in a 50 ° C. vacuum oven for 20 hours with a C-clamp attached and then in a 75 ° C. vacuum oven for 24 hours. Instron measured a force of 127 pounds to pull the aluminum coupon and the quartz slide off.

C. Use as a glue for pellicle polymers

10 g of poly (HFIB / VF) (Example 2A below) are dissolved in 40 g of 2-heptanone, 1 g of decolorized carbon + 1 g of chromatography alumina + 1 g of chromatography silica gel are added, filtered through a 0.45 μPTFE syringe filter, A pellicle polymer poly (HFIB / VF) was prepared as a film by casting on a Teflon ™ FEP sheet using a 5 mil casting knife and air drying. The poly (HFIB / VF) film thus prepared can be removed from the Teflon ™ FEP sheet as a clear, colorless film approximately 0.5-1 mil thick.

The glue solution was then prepared. The solution was prepared by dissolving 0.1 g of poly (TFE / TrP) prepared above in 1 g of hexafluorobenzene.

The glue solution was used to make several 1/2 "spots on an aluminum coupon 1" wide by 3 "long and 122 mils thick. The glue spots were air dried for 39 minutes and the coupons were then placed in a 60 ° C. air oven. 8 minutes As soon as the aluminum coupon was removed from the oven in a hot state, the poly (HFIB / VF) film sample was pressed down lightly with a finger over the poly (TFE / TrP) attachment. Was markedly wetted and stuck to the poly (TFE / TrP) spot While the aluminum coupon was hot, it was difficult to stretch and pull off the poly (HFIB / VF) film, but when the aluminum coupon returned to room temperature The poly (HFIB / VF) film was torn rather than peeled from aluminum The adhesive bond between the glue polymer [poly (TFE / TrP)] and the pellicle polymer [poly (HFIB / VF)] was very strong, The strength of the polymer was surpassed.

Example 8-HFIB / VF

A. Polymerization of Hexafluoroisobutylene (HFIB) and Vinyl Fluoride (VF)

200 ml of water and 0.05 g of Bajo ™ 56 WSP initiator were placed in a 400 ml autoclave. After cooling and venting the autoclave, 80 g of hexafluoroisobutylene and 25 g of vinyl fluoride were added. After shaking for 48 hours at 50 ° C., the autoclave was evacuated and an milky blue emulsion was recovered. The emulsion was stirred vigorously in a Waring blender, filtered off, and washed four times with 100 ml of methyl alcohol in the Waring blender. Drying under pump vacuum for 6 days gave 30 g of white powder and lumps.

Elemental analysis found: 34.80% C, 2.57% H

(C ₄ F ₆ H ₂ ) ₄₇ Theoretical value of (C ₂ H ₃ F) ₅₃ : 34.79% C, 2.51% H

DSC, 10 ° C / min, nitrogen: Tg = 70 ° C (secondary heating)

Tm not detected

Intrinsic viscosity, THF, 25 ℃: 0.379 dL / g

GPC (out of THF) Mw = 192,000

Mn = 92,000

Another poly (HFIB / VF) sample was prepared by the same emulsion polymerization method and its thermal transfer properties were observed in detail with a tuned DSC. Upon secondary heating, glass transitions were detected at 69.5 ° C and 195 ° C. Melt transition was not observed in both primary heating and secondary heating.

Solution Preparation and Results:

A solution was prepared by rolling 10 g of polymer with 40 g of 2-heptanone and filtered through a 0.45 μ glass microfiber syringe filter (Watman, Motorcycles ™). The filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

A HFIB: VF solution was spin coated onto a CaF ₂ substrate to produce a polymer film 9239 mm thick. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between absorbance of HFIB: VF (inverse of microns) versus wavelength lambda (λ) in nm is shown as sample 18 in FIG. 15. 157 nm absorbance / micron was determined to be 0.005 / micron. 193 nm absorbance / micron was determined to be -0.00082 / micron. 248 nm absorbance / micron was determined to be -0.002 / micron.

B. Use as a glue for quartz and aluminum

Aluminum coupons 1 "wide, 3" long, 122 mils thick and quartz slides 1 "wide, 3" long, 65 mils thick were both washed with CF ₂ ClCCl ₂ F and air dried.

2 g of poly (HFIB / VF) prepared above and 18 g of acetone were rolled at room temperature to obtain a clear colorless solution which was passed through a 0.45 μ glass fiber filter. Three drops of this solution were placed on one end of the aluminum coupon, on which the quartz slide was pushed down so that the last inch of the quartz slide overlapped over the last inch of the aluminum coupon. This squeezed excess fluid and wetted the areas where the residual polymer solution overlapped and spread evenly over it. Two C-clamps (Stock No. 72020, ACCO USA Inc., 60090, Wheeling AC Plaza, Illinois, USA) hold the aluminum coupon and quartz slide in place and allow the acetone solvent to stand for 3 days at room temperature. Evaporated. One such assembly was heated in a 50 ° C. vacuum oven for 16 hours with the C-clamp still attached. The force required to remove the assembly from the oven, cool, remove the C-clamps, and pull the quartz slide off the aluminum coupon was measured by Instron using a jaw interval of 3 "and a crosshead speed of 1" / min. . One pound of force was needed. The other of these assemblies was heated in a 50 ° C. vacuum oven for 16 hours with a C-clamp attached and then in a 75 ° C. vacuum oven for 24 hours. Instron measured a force of 0.6 pounds to pull the aluminum coupons and quartz slides apart.

Example 9-VF2 / PMVE

A. Polymerization of Vinylidene Fluoride (VF2) and Perfluoromethylvinyl Ether (PMVE)

In a 210 mL autoclave 50 mL CF ₂ ClCCl ₂ F and 10 mL of about 0.2 M DP in CF ₃ CFHCFHCF ₂ CF ₃ solvent were added. The autoclave was cooled, evacuated and 26 g of VF2 and 33 g of PMVE were added. After shaking overnight at ambient temperature (18-26 ° C.), the autoclave was evacuated and the viscous solution was recovered. Excess solvent was evaporated under nitrogen and the polymer was dried under vacuum at room temperature for 72 hours and then dried at 75 ° C. in a vacuum oven for 28 hours to give 33 g.

Elemental analysis found: 29.64% C, 1.73% H

Theoretical value of (C ₂ F ₂ H ₂ ) ₅ (C ₃ F ₆ O) ₂ : 29.47% C, 1.55% H

DSC, 10 ° C / min, nitrogen: Tg =-32 ° C (secondary heating)

Intrinsic viscosity, CF ₃ CFHCFHCF ₂ CF ₃ , 25 ° C.: 0.722 dL / g

Solution Preparation and Results:

4 g of this polymer were rolled with 16 g of hexafluorobenzene to prepare a solution. This solution was passed through a 0.45 μ glass microfiber syringe filter (Watman, Motorcycles ™) and the filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

A 5: 2 VF2: PMVE solution was spin coated onto a CaF ₂ substrate to prepare a polymer film having a thickness of 72750 mm 3. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between the absorbance (inverse of microns) of the 5: 2 VF2: PMVE versus the wavelength lambda (λ) in nm is shown as sample 19 in FIG. 15. 157 nm absorbance / micron was determined to be 0.016 / micron. 193 nm absorbance / micron was determined to be 0.006 / micron. 248 nm absorbance / micron was determined to be 0.004 / micron.

B. Use as a glue for quartz and aluminum

Aluminum coupons 1 "wide, 3" long, 122 mils thick and quartz slides 1 "wide, 3" long, 65 mils thick were both washed with CF ₂ ClCCl ₂ F and air dried.

About 0.2 g of poly (VF2 / PMVE) was cut into three to four small pieces and placed on one end of an aluminum coupon. On top of that, the quartz slide was pushed down so that the last inch of the quartz slide overlapped the last inch of the aluminum coupon. Two C-clamps (stock number 72020, ACCO USA Inc., 60090 Illinois Wheeling AC Plaza 770-S) are used to hold the aluminum coupon and the quartz slide in place and the assembly is still It was left attached for 22 hours in a 76-80 ° C. vacuum oven, causing the polymer to spread as a clear colorless layer, with excess polymer being pushed out of the edges. The force required to remove the assembly from the oven, cool, remove the C-clamps, and pull the quartz slide off the aluminum coupon was measured by Instron using a jaw interval of 3 "and a crosshead speed of 1" / min. . A force of 105.3 pounds was needed. Separation took place in the polymer layer and residual polymer remained on aluminum and quartz. Another similarly prepared sample required 101.0 pounds of force to pull out and therefore an average of 103 pounds of force.

Example 10-VF2 / PPVE

50 ml of CF ₂ ClCCl ₂ F was placed in a 210 ml autoclave, cooled to <-20 ° C, and 10 ml of about 0.2 M DP in CF ₃ CFHCFHCF ₂ CF ₃ was added. The autoclave was evacuated and 33 g of perfluoro (methyl vinyl ether) (PMVE) and 13 g of vinylidene fluoride (VF 2) were added. The autoclave was shaken overnight at room temperature to give a solution which was evaporated to give a soft polymer which was then dried under pump vacuum for 29 hours and dried in a 75 ° C. vacuum oven for 20 hours. Thus, 31 g of a soft polymer suitable for use as a glue was obtained.

Theoretical value of (C ₂ H ₂ F ₂ ) ₁₃ (C ₃ F ₆ O) ₁₀ : 26.98% C, 1.05% H

Found: 27.21% C, 0.88% H

DSC, 10 ° C / min, nitrogen: Tg =-29 ° C (secondary heating)

Intrinsic viscosity, 2-heptanone: 0.166 dL / g

Solution Preparation and Results:

4 g of this polymer were rolled with 16 g of hexafluorobenzene to prepare a solution. This solution was passed through a 0.45 μ glass microfiber syringe filter (Watman, Motorcycles ™) and the filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

A polymer film having a thickness of 25970 mm 3 was prepared by spin coating a 13:10 VF ₂ : PMVE solution onto a CaF ₂ substrate. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between the absorbance (inverse of microns) and wavelength lambda (λ) in units of 13:10 VF2: PMVE is shown as sample 20 in FIG. 16. 157 nm absorbance / micron was determined to be 0.034 / micron. 193 nm absorbance / micron was determined to be 0.015 / micron. 248 nm absorbance / micron was determined to be 0.018 / micron.

Example 11-VF2 / PPVE

A. Polymerization of Vinylidene Fluoride (VF2) and Perfluoro (propyl Vinyl Ether) (PPVE)

50 ml of CF ₂ ClCCl ₂ F was placed in a 210 ml autoclave, cooled to <-20 ° C, and 10 ml of about 0.2 M DP in CF ₃ CFHCFHCF ₂ CF ₃ was added. The autoclave was cooled, evacuated and 13 g of VF2 and 53 g of PPVE were added. After shaking overnight at ambient temperature (22-26 ° C.), the autoclave was evacuated and the solution recovered. Excess solvent was evaporated under nitrogen and the polymer was dried under vacuum at room temperature for 72 hours and at 75 ° C. for 28 hours to give 45 g.

Elemental Analysis Found: 26.17% C, 0.88% H

Theoretical value of (C ₂ F ₂ H ₂ ) ₇ (C ₅ F ₁₀ O) ₅ : 26.34% C, 0.79% H

DSC, 10 ° C / min, nitrogen: Tg =-32 ° C (secondary heating)

Intrinsic viscosity, hexafluorobenzene, 25 ° C: 0.169 dL / g

Solution Preparation and Results:

4 g of this polymer were rolled with 16 g of hexafluorobenzene to prepare a solution. This solution was passed through a 0.45 μ glass microfiber syringe filter (Watman, Motorcycles ™) and the filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

A polymer film having a thickness of 29874 mm 3 was prepared by spin coating a 7: 5 VF ₂ : PPVE solution onto a CaF ₂ substrate. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between the absorbance of 7: 5 VF2: PPVE (inverse of microns) to the wavelength lambda (λ) in nm is shown as sample 21 in FIG. 15. 157 nm absorbance / micron was determined to be 0.028 / micron. 193 nm absorbance / micron was determined to be -0.003 / micron. 248 nm absorbance / micron was determined to be -0.00074 / micron.

B. Use as a glue for pellicle polymers

10 g of poly (HFIB / VF) (Example 8A above) are dissolved in 40 g of 2-heptanone, 1 g of decolorized carbon + 1 g of chromatography alumina + 1 g of silica gel are added, filtered through a 0.45 μPTFE syringe filter, and Teflon Poly (HFIB / VF) was prepared as a polymer film by casting on a ™ FEP sheet using a 5 mil casting knife and air drying. The poly (HFIB / VF) film thus prepared can be removed from the Teflon ™ FEP sheet as a clear, colorless film approximately 0.5 to 1 mil thick.

The glue solution was then prepared. The solution was prepared by dissolving 0.1 g of poly (VF 2 / PPVE) prepared above in 1 g of hexafluorobenzene.

This glue solution was used to make about 1/2 "spots on an aluminum coupon 1" wide by 3 "long and 122 mils thick. The glue spots were air dried for 39 minutes and the coupons were placed under nitrogen in a 62 ° C. oven. 13 minutes As soon as the aluminum coupon was removed from the oven in a hot state, the poly (HFIB / VF) film sample was pressed down lightly with a finger on the poly (VF2 / PPVE) attachment and pressed down. The poly (HFIB / VF) film was torn when pulled or peeled off as in lap shear.The adhesive bond between the glue polymer [poly (VF2 / PPVE)] and the pellicle polymer [poly (HFIB / VF)] Very strong, exceeding the strength of the pellicle polymer.

Example 12-VF2 / HFP

A. Poly (vinylidene fluoride / hexafluoropropylene) (VF2 / HFP) sample

Vinylidene fluoride / hexafluoropropylene samples were prepared and characterized by the method described in US Pat. No. 4,985,520 (1991.1.15).

Composition by fluorine NMR in deuterium acetone: 21 mol% VF 2, 79 mol% HFP

DSC, 10 ° C / min, nitrogen: Tg = -22.5 ° C (secondary heating)

Intrinsic viscosity, acetone, 25 ° C .: 0.753 dL / g

Solution Preparation and Results:

A solution was prepared by rolling 3 g of poly (VF2 / HFP) with 17 g of 2-heptanone and filtered through a 0.45 μ glass microfiber syringe filter (Watman, Motorcycles ™). The filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

A 79:21 VF2: HFP solution was spin coated onto a CaF ₂ substrate to produce a polymer film 13000 mm thick. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between absorbance (inverse of microns) versus wavelength lambda (λ) in 79:21 VF2: HFP is shown as sample 22 in FIG. 15. 157 nm absorbance / micron was determined to be 0.014 / micron. 193 nm absorbance / micron was determined to be -0.002 / micron. 248 nm absorbance / micron was determined to be -0.00056 / micron.

B. Use as a glue for quartz and aluminum

Aluminum coupons 1 "wide, 3" long, 122 mils thick and quartz slides 1 "wide, 3" long, 65 mils thick were both washed with CF ₂ ClCCl ₂ F and air dried.

About 0.2 g of poly (VF 2 / HFP) was cut into three to four small pieces and placed on one end of an aluminum coupon. On top of that, the quartz slide was pushed down so that the last inch of the quartz slide overlapped the last inch of the aluminum coupon. Two C-clamps (stock no. 72020, ACCO USA Inc., 60090 Illinois Wheeling AC Plaza 770-S) hold the aluminum coupon and quartz slide in place and the C-clamp still attached It was left for 22 hours in a 76-80 ° C. vacuum oven, which caused the polymer to spread as a clear colorless layer. The force required to remove the assembly from the oven, cool, remove the C-clamps, and pull the quartz slide off the aluminum coupon was measured by Instron using a jaw interval of 3 "and a crosshead speed of 1" / min. . 133.3 pounds of force was needed. Another similarly prepared sample required 121.6 pounds of force to pull apart and therefore an average of 127 pounds of force. In the second of the two experiments, separation took place in the polymer layer and residual polymer remained in both aluminum and quartz. In the first of the two experiments, separation occurred between the polymer and the glass. In either case, the residual polymer could be pulled cleanly from glass and aluminum into a single piece.

C. Use as a glue for pellicle polymers

10 g of poly (HFIB / VF) (Example 2A above) were dissolved in 40 g of 2-heptanone, 1 g of decolorized carbon + 1 g of chromatography alumina + 1 g of silica gel were added, filtered through a 0.45 μPTFE syringe filter, and teflon ™ was cast on a FEP sheet using a 5 mil casting knife and air dried. The poly (HFIB / VF) film thus prepared could be removed from the Teflon ™ FEP sheet as a clear, colorless film approximately 0.5-1 mil thick.

The glue solution was then prepared. The solution was prepared by dissolving 0.1 g of poly (VF 2 / HFP) prepared above in 1 g of hexafluorobenzene.

The glue solution was used to make about 1/2 "spots on an aluminum coupon 1" wide by 3 "long and 122 mils thick. The glue spots were air dried for 39 minutes and the coupons were then placed in a 62 ° C. nitrogen blanket oven. 13 minutes As soon as the aluminum coupon was removed from the oven in a hot state, the poly (HFIB / VF) film sample was pressed down lightly with a finger on the poly (VF2 / HFP) attachment and pressed down. When the poly (HFIB / VF) film was pulled off as it was in the wrap sheer, when the poly (HFIB / VF) film was peeled off by itself, an adhesion failure occurred between the poly (VF2 / HFP) glue and aluminum, The VF2 / HFP) adhesive layer peels off cleanly from aluminum and shows no debonding from poly (HFIB / VF), which indicates that adhesion between pellicle polymer [poly (HFIB / VF)] and glue polymer [poly (VF2 / HFP)] Excellent It informs.

Example 13-HFP / PMVE / VF2

The 210 ml Hastelloy C autoclave was cooled to <-20 ° C. and 20 ml of about 0.17 M DP in CF ₃ CFHCFHCF ₂ CF ₃ were added. The autoclave was evacuated and 33 g of perfluoro (methyl vinyl ether) (PMVE), 26 g of vinylidene fluoride (VF 2), 26 g of hexafluoropropylene (HFP) and 1 g of anhydrous hydrogen chloride (chain transfer agent) were added. The autoclave was shaken overnight at room temperature to give a colorless oil, which was clear tack suitable for use as glue by removing volatile components for 24 hours in air, 19 hours under pump vacuum and then 5 days in a 75 ° C. vacuum oven. 47 g of a resin was obtained.

Composition by fluorine NMR: 63.1 mol% VF2

27 mol% PMVE

10 mol% HFP

Intrinsic viscosity, acetone, 25 ° C: 0.120 dL / g

Solution Preparation and Results:

4 g of this polymer were rolled with 12 g of 2-heptanone to produce a cloudy solution. This solution was passed through 0.45 μ glass microfibers and a Teflon ™ Syringe Filter (Watman, Motorcyclel ™), and the filtrate was used to spin coat a thick film on an optical substrate for absorbance measurements.

A 10:27:63 HFP: PMVE: VF2 solution was spin coated onto a CaF ₂ substrate to produce a polymer film having a thickness of 316500 mm 3. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between absorbance (unit: inverse of microns) versus wavelength lambda (λ) in 10:27:63 HFP: PMVE: VF2 is shown as Sample 23 in FIG. 157 nm absorbance / micron was determined to be 0.008 / micron. 193 nm absorbance / micron was determined to be -0.00048 / micron. 248 nm absorbance / micron was determined to be -0.00045 / micron.

Example 14-HFIB / VF

Two 3/8 "diameter stainless steel balls were placed in an 85 ml autoclave, sealed, evacuated, cooled to <-20 ° C and sucked about 10 ml of about 0.17 M DP in CF ₂ CFHCFHCF ₂ CF ₃ . The clave was further cooled, 70 g of hexafluoroisobutylene (HFIB) was added at about −50 ° C., and 10 psig liquid vinyl fluoride (VF) was added at about −35 ° C. The autoclave filled with liquid was shaken. The clave pressure was fully used at 7780 psi at 25 ° C. and tested at 103 psig for about 10 hours at 29 ° C. The solid polymer product was dried under pump vacuum for 72 hours to obtain a glass transition temperature. 57 g of a white solid at 115 ° C were obtained.

(HFIB) ₅₉ (VF) Theoretical value of ₄₁ : 33.04% C, 2.11% H

Found: 33.02% C, 2.31% H

DSC, 10 ° C / min, nitrogen: Tg = 115 ° C (secondary heating)

Tm not detected (primary heating and secondary heating)

Intrinsic viscosity, THF, 25 ° C: 0.183 dL / g

Solution Preparation and Results:

A solution was prepared by rolling 12 g of this polymer with 48 g of 2-heptanone. This solution was passed through 0.45 μ glass microfibers and Teflon ™ Syringe Filter (Watman, Motorcycles ™), and the filtrate was used to spin coat a thick film on an optical substrate for absorbance measurements.

A 10: 7 HFIB: VF solution was spin coated onto a CaF ₂ substrate to produce a polymer film 7500 mm thick. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between absorbance of 10: 7 HFIB: VF (inverse of microns) versus wavelength lambda (λ) in nm is shown in Sample 16 in FIG. 157 nm absorbance / micron was determined to be -0.013 / micron. 193 nm absorbance / micron was determined to be -0.016 / micron. 248 nm absorbance / micron was determined to be -0.011 / micron.

Example 15-PDD / PMVE

25 mL CF ₂ ClCCl ₂ F was placed in a 75 mL autoclave, cooled to <-20 ° C., 10 mL of about 0.2 M DP in CF ₃ CFHCFHCF ₂ CF ₃ and 11.6 mL of perfluorodimethyldioxol (PDD) were added. It was. The autoclave was evacuated and 4.5 g of perfluoro (methylvinylether) (PMVE) was added. The autoclave was shaken overnight at room temperature to obtain a gelatinous product which was evaporated and then further dried under pump vacuum for 29 hours and in a 75 ° C. vacuum oven for 20 hours. This gave 18 g of product.

Theoretical value of (PDD) ₆ (PMVE) ₅ : 23.56% C

Found: 23.87% C

DSC, 10 ° C./min, nitrogen: Tg = 133 ° C.

Intrinsic viscosity, fluorine nut ™ FC-40: 0.161 dL / g

Solution Preparation and Results:

4 g of this polymer were rolled with 16 g of Fluorinant ™ FC-40 to prepare a cloudy solution. This solution was passed through a 0.45 μ glass microfiber syringe filter (Watman, Motorcycles ™), followed by the addition of 0.6 g chromatography alumina and 0.6 g chromatography silica gel, followed by 0.45 μ Teflon ™ syringe filter (Watman, Passed through Motorcycle ™. The filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

A 6: 5 PDD: PFMVE solution was spin coated onto a CaF ₂ substrate to produce a polymer film having a thickness of 12450 mm 3. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between the absorbance (in reciprocal of microns) and wavelength lambda (λ) in 6: 5 PDD: PFMVE is shown as sample 25 in FIG. 16. 157 nm absorbance / micron was determined to be 0.209 / micron. 193 nm absorbance / micron was determined to be 0.006 / micron. 248 nm absorbance / micron was determined to be 0.013 / micron.

Example 16-VF / ClDFE

25 mL CF ₂ ClCCl ₂ F was placed in a 75 mL autoclave, cooled to <-20 ° C., and 10 mL of about 0.17M DP in CF ₃ CFHCFHCF ₂ CF ₃ was added. The autoclave was evacuated and 6.4 g of vinyl fluoride (VF) and 9.8 g of 1-chloro-2,2-difluoroethylene (ClDFE) were added. The autoclave was shaken overnight at room temperature to obtain a moist paste, which was dried under pump vacuum for 4 days and dried in a 75 ° C. vacuum oven for 28 hours. This gave 8 g of product.

Theoretical value of (C ₂ H ₃ F) ₂₀ (C ₂ HF ₂ Cl) ₁₁ : 37.16% C, 3.57% H

Found: 37.39% C, 3.30% H

DSC, 10 ° C / min, nitrogen: Tg = 97 ° C (primary heating)

Tg not detected in secondary heating

Intrinsic viscosity, acetone: 0.220 dL / g

Solution Preparation and Results:

4 g of this polymer was rolled with 16 g of heptanone to prepare a solution. This solution was passed through a 0.45 μ glass microfiber syringe filter (Watman, Motorcycles ™) and the filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

A 20:11 VF: ClDFE solution was spin coated onto a CaF ₂ substrate to produce a 9461 mm thick polymer film. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between 20:11 VF: ClDFE absorbance (inverse of microns) versus wavelength lambda (λ) is shown as sample 26 in FIG. 17. 157 nm absorbance / micron was determined to be 0.226 / micron. 193 nm absorbance / micron was determined to be 0.036 / micron. 248 nm absorbance / micron was determined to be 0.003 / micron.

Example 17-PDD / VF2

75 ㎖ and the autoclave was cooled to _{<-20 ℃, CF 3 CFHCFHCF 2} CF 3 10 ㎖, CF 3 CFHCFHCF 2 CF to about 0.17M DP 5㎖ and perfluoroalkyl of ₃ was placed dimethyl-dioxole (PDD) 20 g. The autoclave was evacuated and 13 g of vinylidene fluoride (VF 2) was added. The autoclave was shaken overnight at room temperature to give a viscous oil, which was removed in air, under a pump vacuum for 32 hours and then in a 75 ° C. vacuum oven for 23 hours to give 16 g of a white resin.

Theoretical value of (PDD) ₁ (VF2) ₂ : 29.05% C, 1.08% H

Found: 29.35% C, 1.08% H

DSC, 10 ° C / min, Nitrogen: 52 ° C (weak)

Intrinsic viscosity, hexafluorobenzene, 25 ° C: 0.278

Solution Preparation and Results:

A solution was prepared by rolling 2 g of polymer (PDD / VF 2) with 8 g of 2-hexafluorobenzene. This solution was passed through a 0.45 μ glass microfiber syringe filter (Watman, Motorcycles ™) and the filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

A polymer film having a thickness of 82000 mm 3 was prepared by spin coating a 1: 2 PDD: VF ₂ solution onto a CaF ₂ substrate. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between the absorbance (unit: inverse of microns) of 1: 2 PDD: VF2 versus wavelength lambda (λ) in nm is shown as sample 27 in FIG. 157 nm absorbance / micron was determined to be 0.009 / micron. 193 nm absorbance / micron was determined to be 0.003 / micron. 248 nm absorbance / micron was determined to be -0.00030 / micron.

Example 18A-PDD / VF2

75 ㎖ and the autoclave was cooled to _{<-20 ℃, CF 3 CFHCFHCF 2} CF 3 20 ㎖, CF 3 CFHCFHCF 2 CF to about 0.17M DP 5㎖ and perfluoroalkyl of ₃ was placed dimethyl-dioxole (PDD) 20 g. The autoclave was evacuated and 6 g of vinylidene fluoride (VF 2) was added. The autoclave was shaken overnight at room temperature to give a viscous oil, which was removed in air, under a pump vacuum for 32 hours and then in a 75 ° C. vacuum oven for 23 hours to give 16 g of a white resin.

Theoretical value of (C ₅ F ₈ O ₂ ) ₂ (C ₂ H ₂ F ₂ ) ₁ : 26.11% C, 0.37% H

Found: 26.03% C, 0.53% H

DSC, 10 ° C / min, Nitrogen: 96 ° C (weak)

Intrinsic viscosity, hexafluorobenzene, 25 ℃: 0.671

Solution Preparation and Results:

A cloudy solution was prepared by rolling 2 g of poly (PDD / VF2) with 18 g of 1H-perfluorohexane. Pass this solution through a 0.45 μ glass microfiber syringe filter (Watman, Motorcycles ™) (help filtration using chromatographic silica gel pads) and add an additional 2 in amounts that almost compensate for the amount lost due to evaporation. After addition of -H-perfluorohexane, it was filtered again through a 0.45μ Teflon ™ syringe filter (Watman, Motorcycles ™). The clear filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

Example 18B-PDD / VF2

In <which, Teflon ™ coating 400㎖ stainless steel autoclave cooled to -20 ℃ CF ₃ CFHCFHCF ₂ CF ₃ to _{90 ㎖, CF 3 CFHCFHCF 2 CF} 3 about 0.1M DP 30㎖ and perfluoro dimethyl dioxol were placed in 120g . The autoclave was pressurized with nitrogen to 100 psi and vented 10 times. Finally, 58 g of vinylidene fluoride (VF 2) was added and the autoclave was shaken at room temperature overnight. The thick gel thus obtained was dried under nitrogen, then under pump vacuum and finally dried in a 75 ° C. vacuum oven for 4 days to give 122 g of a white resin.

Theoretical value of (C ₅ F ₈ O ₂ ) ₅ (C ₂ H ₂ F ₂ ) ₈ : 28.42% C, 0.93% H

Found: 28.22% C, 1.16% H

DSC, 10 ° C / min, nitrogen: 59 ° C

Intrinsic viscosity, hexafluorobenzene, 25 ℃: 0.576

Solution Preparation and Results:

A solution was prepared by rolling 1.70 g of poly (PDD / VF 2) with 15.3 g of hexafluorobenzene. This solution was filtered through a 0.45 μ glass microfiber syringe filter (Watman, Motorcycles ™) to give a clear colorless solution. The filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

A polymer film having a thickness of 38298 mm 3 was prepared by spin coating a 5: 8 PDD: VF ₂ solution onto a CaF ₂ substrate. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between the absorbance (unit: inverse of microns) of the 5: 8 PDD: VF2 versus the wavelength lambda (λ) in nm is shown as sample 29 in FIG. 157 nm absorbance / micron was determined to be 0.018 / micron. 193 nm absorbance / micron was determined to be 0.010 / micron. 248 nm absorbance / micron was determined to be 0.000057 / micron.

Example 19A-HFIB / VF2 / VF

50 ml of CF ₂ ClCCl ₂ F was placed in a 210 ml Hastelloy C autoclave, cooled to <-20 ° C, and 15 ml of about 0.2 M DP in CF ₃ CFHCFHCF ₂ CF ₃ was added. The autoclave was evacuated and 32 g of hexafluoroisobutylene (HFIB), 3 g of vinylidene fluoride (VF 2) and 7 g of vinyl fluoride (VF) were added. The autoclave was shaken overnight at room temperature to give a thick paste of white solid, which was dried under nitrogen, under pump vacuum for 70 hours, then in 75 ° C. vacuum oven for 23 hours. This gave 33 g of product, which analysis was consistent with the possible stoichiometric range.

Theoretical value of (C ₄ H ₂ F ₆ ) ₃ (C ₂ H ₃ F) ₁ (C ₂ H ₂ F ₂ ) ₁ : 31.91% C, 1.84% H

(C ₄ H ₂ F ₆ ) ₅ (C ₂ H ₃ F) ₁ (C ₂ H ₂ F ₂ ) ₃ Theoretical value: 31.78% C, 1.81% H

Found: 31.78% C, 1.88% H

DSC, 10 ° C / min, nitrogen: Tg = 48 ° C

Intrinsic viscosity, acetone, 25 ℃: 0.030 dL / g

Solution Preparation and Results:

8 g of this polymer was rolled with 20 g of heptanone to produce a cloudy solution. This solution is passed through a 0.45 μ glass fiber syringe filter (Watman, Motorcycles ™), and a 0.45 μ Teflon ™ syringe filter (Watman, Motorcycles ™) and 0.45 μ Teflon ™ syringe filter (Wattmans, Motorcycles ™ (Through filtration using 1 g of chromatographic alumina pads). The clear filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

Example 19B-HFIB / VF / VF2

200 ml of deionized water and 0.05 g of Bajo ™ 56 WSP initiator were placed in a 400 ml autoclave, pressurized to 100 psi with nitrogen, and evacuated 10 times. The autoclave was cooled to <-20 ° C., evacuated and additionally added 82 g hexafluoroisobutylene (HFIB), 13 g vinylidene fluoride (VF 2) and 14 g vinyl fluoride (VF). The contents of the autoclave were shaken at 50 ° C. for about 64 hours. The mixture of solids and emulsions thus obtained was frozen and thawed. Vacuum filtration and washing twice with 200 mL of water in a filter yielded a downy white solid and a slightly dark yellow lump which was removed. The remaining downy white solid was washed twice more with a filter with 150 ml of methyl alcohol. The downy white solid was suction dried on the filter and then dried under pump vacuum for an additional 5 days to give 16 g of polymer.

Composition by fluorine NMR: 41 mol% HFIB, 37 mol% VF, 22 mol% VF2

DSC, 10 ° C / min, Nitrogen: 71 ° C

Intrinsic viscosity, tetrahydrofuran, 25 ° C .: 0.523

Solution Preparation and Results:

A solution was prepared by rolling 3 g of poly (HFIB / VF / VF2) with 17 g of 2-heptanone. Filter through a 0.45 μ glass microfiber syringe filter (Watman, Motorcycles ™) and then through a 0.45 μ PTFE syringe filter (Wattman, Motorcycles ™) to give a clear but pale yellow solution. The filtrate was used to spin coat the film on the optical substrate for absorbance measurements.

A 41:37:22 HFIB: VF: VF2 solution was spin coated onto a CaF ₂ substrate to produce a 5289 mm thick polymer film. Absorbance / micron was then determined using VUV absorbance measurement.

41:37:22 The relationship between absorbance (in reciprocal microns) versus wavelength lambda (λ) in HFIB: VF: VF2 is shown as Sample 31 in FIG. 157 nm absorbance / micron was determined to be 0.016 / micron. 193 nm absorbance / micron was determined to be -0.010 / micron. 248 nm absorbance / micron was determined to be -0.002 / micron.

Example 20-PDD / TrFE

40 ml of water and 0.1 g of Bajo ™ 56 WSP initiator were placed in a 75 ml autoclave. The autoclave was cooled to <-20 ° C and 10 g of perfluorodimethyldioxol (PDD) was added. The autoclave was evacuated and 5 g of trifluoroethylene (TrFE) was added. Shaking for 10 hours at 70 ° C. gave a polymer mass, which was separated and dried in a 75 ° C. vacuum oven for 72 hours to give 9.9 g of product.

Elemental Analysis Found: 25.51% C, 0.55% H

Theoretical value of (C ₅ F ₈ O ₂ ) ₁ (C ₂ F ₃ H) ₁ : 25.79% C, 0.31% H

DSC, 10 ° C / min, nitrogen: Tg = 150 ° C (weak, secondary heating)

Intrinsic viscosity, hexafluorobenzene, 25 ° C: 1.3 dL / g

Solution Preparation and Results:

1 g of this polymer was rolled with 33 g of Fluorinant ™ Fc-75 to prepare a solution and filtered through a 0.45 μ glass microfiber syringe filter (Watman, Motorcyclel ™). The filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

A polymer film having a thickness of 7688 mm 3 was prepared by spin coating a 1: 1 PDD: TrFE solution onto a CaF ₂ substrate. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between absorbance (unit: inverse of microns) of 1: 1 PDD: TrFE to wavelength lambda (λ) in nm is shown in Sample 16 in FIG. 157 nm absorbance / micron was determined to be 0.03 / micron. 193 nm absorbance / micron was determined to be -0.004 / micron. 248 nm absorbance / micron was determined to be -0.001 / micron.

Example 21-CTFE / VF

25 mL CF ₂ ClCCl ₂ F was placed in a 75 mL autoclave, cooled to −20 ° C., and 5 mL of about 0.1 M DP in CF ₃ CFHCFHCF ₂ CF ₃ was added. The autoclave was evacuated and 17 g of chlorotrifluoroethylene (CTFE) and 7 g of vinyl fluoride (VF) were added. The autoclave was shaken overnight at room temperature to obtain a swollen gel, which was dried in air, under a pump vacuum for 96 hours and then in a 75 ° C. vacuum oven for 25 hours. Thus, 18 g of a polymer was obtained.

Theoretical value of (C ₂ F ₃ Cl) ₁ (C ₂ H ₃ F) ₁ : 29.56% C, 1.86% H, 21.82% Cl

Found: 29.74% C, 1.83% H, 21.80% Cl

DSC, 10 ° C / min, nitrogen: 86 ° C (primary heating)

Intrinsic viscosity, acetone, 25 ℃: 1.08 dL / g

Solution Preparation and Results:

A solution was prepared by rolling 2 g of this polymer with 15 g of heptanone. This solution was passed through a 0.45 μ glass fiber syringe filter (Watman, Motorcycles ™) and the filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

A 1: 1 CTFE: VF solution was spin coated onto a CaF ₂ substrate to produce polymer films of thickness 1850 mm 3 and 17644 mm 3. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between the absorbance of 1: 1 CTFE: VF (inverse of microns) versus wavelength lambda (λ) in nm is shown as sample 6b in FIG. 18. The 157 nm absorbance / micron determined from the thicker film was 0.388 / micron. The 193 nm absorbance / micron determined from the thicker film was 0.016 / micron. The 248 nm absorbance / micron determined from the thicker film was 0.006 / micron.

Sample 10-VF2 / TrFE

25 mL CF ₂ ClCCl ₂ F was placed in a 75 mL autoclave, cooled to −20 ° C., and 5 mL of about 0.1 M DP in CF ₃ CFHCFHCF ₂ CF ₃ was added. The autoclave was evacuated and 9.6 g of vinylidene fluoride (VF 2) and 12 g of trifluoroethylene (TrFE) were added. The autoclave was shaken at room temperature overnight to obtain a moist white solid, which was dried under pump vacuum and then in a 75 ° C. vacuum oven for 24 hours. Thus, 14g of polymer was obtained.

Theoretical value of (C ₂ H ₃ F ₂ ) ₅ (C ₂ F ₃ H) ₂ : 34.73% C, 2.50% H

Found: 34.78% C, 2.48% H

DSC, 10 ° C./min, nitrogen: first heat, Tg = 55 ° C.

Secondary heating, Tg = 98 and 147 ° C

Intrinsic viscosity, acetone, 25 ℃: 1.087 dL / g

Solution Preparation and Results:

A solution was prepared by rolling 3.11 g of this polymer with 34.32 g of 1-methoxy-2-propanol acetate. The cloudy solution containing the microparticles thus prepared was difficult to pass through a 0.45 μ glass fiber syringe filter (Watman, Motorcycleel ™). 2.82 g of this solution was evaporated to afford 0.220 g (7.8 wt% solids; expected to be 8.3% if no solids were removed by filtration). A thick film was spin coated onto the optical substrate for absorbance measurements.

A 5: 2 VF2: TrFE solution was spin coated onto a CaF ₂ substrate to produce a polymer film having a thickness of 4500 mm 3. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between the absorbance of 5: 2 VF2: TrFE (inverse of microns) versus the wavelength lambda (λ) in nm is shown as sample 10 in FIG. 18. 157 nm absorbance / micron was determined to be 0.924 / micron. 193 nm absorbance / micron was determined to be 0.188 / micron. 248 nm absorbance / micron was determined to be 0.083 / micron.

Example 23-HFIB / VOH

A. Hexafluoroisobutylene (HFIB) / vinyl acetate (VOAc) copolymer

In a 400 ml autoclave 50 ml of CF ₂ ClCCl ₂ F, 27 ml of vinyl acetate and 50 ml of about 0.1 M DP in CF ₃ CFHCFHCF ₂ CF ₃ . The autoclave was cooled, evacuated and additionally 49 g of HFIB was added. Shaking overnight at room temperature gave a viscous pale yellow oil. 400 ml of methyl alcohol was added to precipitate the polymer. Filtration, drying under pump vacuum, and drying in a 75 ° C. vacuum oven for 19 hours yielded 52 g of poly (HFIB / VOAc) with an intrinsic viscosity (acetone, 25 ° C.) of 0.13.

B. Hexafluoroisobutylene (HFIB) / Vinyl Alcohol (VOH) Copolymer

50 g of poly (HFIB / VOAc) prepared above, 500 ml of methyl alcohol, and 25 ml of 25% by weight sodium methoxide in methyl alcohol were refluxed for 6 hours. Additional methyl alcohol was added because about 860 ml of methyl alcohol was distilled off over this period. The obtained polymer solution was added to water to obtain a rubbery precipitate. The water was decanted off and the precipitate was again dissolved in 200 ml of methyl alcohol and reprecipitated with 500 ml of water in a Waring blender. Vacuum filtration, drying under a pump vacuum, and then drying in a 75 ° C. vacuum oven for 24 hours yielded 37 g of poly (HFIB / VOH) as off-white granules.

Theoretical value of (C ₄ H ₂ F ₆ ) ₁ (C ₂ H ₄ O) ₁ : 34.63% C, 2.91% H

Found: 34.34% C, 2.73% H

DSC, 10 ° C / min, nitrogen: Tg = 90 ° C (secondary heating)

Solution Preparation and Results:

A solution was prepared by rolling 3.28 g of this polymer with 34.91 g of 1-methoxy-2-propanol acetate. This solution was passed through a 0.45 μ glass fiber syringe filter (Watman, Motorcycles ™) to give a slightly pale yellow solution. The solution was treated with 0.4 g of bleached carbon and filtered again, then with 0.58 g of silica gel and filtered third. The solution was still pale yellow, but now it is not blurry. The filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

A 1: 1 HFIB: VA solution was spin coated onto a CaF ₂ substrate to produce a polymer film having a thickness of 1350 mm 3. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between absorbance of 1: 1 HFIB: VA (inverse of microns) to wavelength lambda (λ) in nm is shown as sample 32 in FIG. 157 nm absorbance / micron was determined to be 0.350 / micron. 193 nm absorbance / micron was determined to be -0.047 / micron. 248 nm absorbance / micron was determined to be -0.107 / micron.

Sample 12-HFP / TrFE

25 mL CF ₂ ClCCl ₂ F was placed in a 75 mL autoclave, cooled to <-20 ° C., and 5 mL of about 0.17 M DP in CF ₃ CFHCFHCF ₂ CF ₃ was added. The autoclave was evacuated and 12 g of hexafluoropropylene (HFP) and 12 g of trifluoroethylene (TrFE) were added. The autoclave was shaken overnight at room temperature to obtain a damp white solid, which was dried under pump vacuum for 22 hours and then in a 75 ° C. vacuum oven for 24 hours. This gave 12 g of product.

Composition by fluorine NMR: 2 mol% HFP, 98 mol% TrFE

DSC, 10 ° C./min, nitrogen: Tm = 179 ° C., Tg not detected

Intrinsic viscosity, acetone, 25 ℃: 0.912 dL / g

Solution Preparation:

2.5 g of poly (HFP / TrFE) was rolled with 50 mL of propylene glycol methyl ether acetate to form a cloudy solution. A clear filtrate was obtained by filtration through a 0.45 μ PTFE syringe filter (Watman, Motorcycles ™). The filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

A polymer film having a thickness of 1389 mm 3 was prepared by spin coating a 2:98 HFP: TrFE solution onto a CaF ₂ substrate. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between absorbance of HFP: TrFE (inverse of microns) versus wavelength lambda (λ) in nm is shown in Sample 8 in FIG. 157 nm absorbance / micron was determined to be 1.37 / micron. 193 nm absorbance / micron was determined to be 0.143 / micron. 248 nm absorbance / micron was determined to be -0.02 / micron.

Sample 14-HFP / TFE

Hexafluoropropylene (HFP) / tetrafluoroethylene (TFE) copolymers were prepared by the method of US Pat. No. 5,478,905 (December 26, 1995). This polymer was 60 wt% HFP and 40 wt% TFE and had an intrinsic viscosity (Fluorinant ™ FC-75 solvent, 25 ° C.) of 0.407 dL / g.

Solution Preparation:

A solution was prepared by rolling 31.6 g of HFP / TFE copolymer with 986 g of PF-5080 (Performance Fluid, manufactured at 3M, believed to be nearly perfluorooctane). Vacuum filtration through a 0.45 μ filter afforded a clear solution. The filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

A 1850 mm thick polymer film was prepared by spin coating a 1: 1 HFP: TFE solution onto a CaF ₂ substrate. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between the absorbance (inverse of microns) and wavelength lambda (λ) in units of 1: 1 HFP: TFE is shown as sample 14 in FIG. 8. 157 nm absorbance / micron was determined to be 3.9 / micron. 193 nm absorbance / micron was determined to be 0.086 / micron. 248 nm absorbance / micron was determined to be 0.073 / micron.

Sample 15-VF2 / CTFE

To a 75 mL autoclave cooled to <-20 ° C. was added 25 mL of CF ₂ ClCCl ₂ F and 5 mL of about 0.1 M DP in CF ₃ CFHCFHCF ₂ CF ₃ . The autoclave was evacuated and 9.6 g of vinylidene fluoride (VF 2) and 17 g of chlorotrifluoroethylene (CTFE) were added. The autoclave was shaken overnight at room temperature to give a viscous white fluid which was evaporated to give an elastic solid which was then dried under pump vacuum for 1 hour and then in a 75 ° C. vacuum oven for 30 hours. This gave 19 g of product.

Theoretical value of (C ₂ F ₂ H ₂ ) ₅ (C ₂ F ₃ Cl) ₄ : 27.50% C, 1.28% H, 18.04% Cl

Found: 27.26% C, 1.41% H, 17.91% Cl

DSC, 10 ° C./min, nitrogen: Tg = 99 ° C.

Intrinsic viscosity, acetone, 25 ℃: 0.546 dL / g

Solution Preparation:

A solution was prepared by rolling 3 g of poly (VF2 / CTFE) with 20 g of 2-heptanone, which was filtered through a 0.45 μ glass fiber syringe filter (Watman, Motorcycles ™). The filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

A polymer film was prepared by spin coating a 5: 4 VF2: CTFE solution onto a CaF ₂ substrate. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between the absorbance (inverse of microns) and wavelength lambda (λ) in 5: 4 VF2: CTFE is shown as Sample 15 in FIG. 157 nm absorbance / micron was determined to be 5.6 / micron. 193 nm absorbance / micron was determined to be 0.27 / micron. 248 nm absorbance / micron was determined to be 0.12 / micron.

Sample 16-PMD / TFE

To <75 ㎖ autoclave was cooled to -20 ℃ CF ₃ CFHCFHCF ₂ CF ₃ of from about _{0.14M DP 5㎖, CF 3 CFHCFHCF 2} CF 3 25㎖ and perfluoro (2-methylene-4-methyl-1,3 11.6 mL of Dioxolane) (PMD) was added. The tube was evacuated and 5 g of tetrafluoroethylene (TFE) was added thereto. The autoclave was shaken overnight at room temperature to give a milky viscous oil. Under nitrogen, 20 g of a resin estimated to be about 2: 1 PMD: TFE copolymer (the monomers were mixed at a ratio of about 2 PMD:1TFE) by pumping under vacuum under a pump vacuum for 76 hours and then in a 75 ° C. vacuum oven for 24 hours. Got it.

DSC, 10 ° C / min, nitrogen: no Tg detected

Intrinsic viscosity, Fluorinner ™ FC-75, 25 ° C: 0.142 dL / g

Solution Preparation:

2.14 g of poly (PMD / TFE) was rolled with 26.2 g of Fluorinant ™ FC-40 to obtain a cloudy solution which was passed through a 0.45 μ glass fiber filter (Watman, Motorcycles ™) and 0.2 g of chromatography silica. After mixing with 0.2 g of bleached carbon, it was passed through a 0.45 μ glass fiber syringe filter (Watman, Motorcycles ™) and finally through a 0.45 μ PTFE syringe filter (Wattman, Motorcycles ™). The filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

A 1: 1 PMD: TFE solution was spin coated onto a CaF ₂ substrate to prepare a polymer film 2207 mm thick. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between absorbance (unit: inverse of microns) of 1: 1 PMD: TFE versus wavelength lambda (λ) in nm is shown in Sample 16 in FIG. 157 nm absorbance / micron was determined to be 1.17 / micron. 193 nm absorbance / micron was determined to be -0.015 / micron. 248 nm absorbance / micron was determined to be 0.07 / micron.

Example 28-PMD / TFE

A 1 ounce glass sample vial with rubber septum was flushed with nitrogen and cooled on dry ice before 3 ml of perfluoro (2-methylene-4-methyl-1,3-dioxolane) and CF ₃ CFHCFHCF 0.5 ml of about 0.17 M DP in ₂ CF ₃ was injected. The vial was placed in ice water and then slowly warmed to room temperature by magnetic stirring for several hours. After about 62 hours at room temperature, the contents of the vial, i.e. the rigid foam, were dried under pump vacuum, then dried in a 150 ° C. vacuum oven for 17 hours, pulverized with a spatula and 4.1 g of white fine powder was obtained.

DSC, 10 ° C / min, nitrogen: Tg = 135 ° C

Intrinsic viscosity, hexafluorobenzene, 25 ° C: 0.155 dL / g

Solution Preparation:

2 g of poly (PMD) was rolled with 18 g of hexafluorobenzene to obtain a solution, which was filtered through a 0.45 μ glass fiber syringe filter (Watman, Motorcycles ™). The filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

The PMD solution was spin coated onto a CaF ₂ substrate to produce a polymer film having a thickness of 14818 mm 3. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between the absorbance (in reciprocal of microns) of the PMD and the wavelength lambda (λ) in nm is shown as sample 33 in FIG. 17. 157 nm absorbance / micron was determined to be 0.603 / micron. 193 nm absorbance / micron was determined to be -0.0007 / micron. 248 nm absorbance / micron was determined to be -0.0001 / micron.

Example 29-PMD / PDD

A 1 ounce glass sample vial with rubber septum was flushed with nitrogen and cooled on dry ice before 3 ml of perfluoro (2-methylene-4-methyl-1,3-dioxolane) (PMD), perfluoro 3 ml of dimethyldioxol (PDD) and 0.5 ml of about 0.17 M DP in CF ₃ CFHCFHCF ₂ CF ₃ were injected. The vial was placed in ice water and then slowly warmed to room temperature by magnetic stirring for several hours. After about 62 hours at room temperature, the contents of the vial, i.e. the rigid foam, were dried under pump vacuum, then dried in a 150 ° C. vacuum oven for 17 hours, pulverized with a spatula to yield 8.6 g of white fine powder.

DSC, 10 ° C / min, nitrogen: Tg = 147 ° C

Solution Preparation:

2 g of poly (PMD / PDD) were rolled with 18 g of hexafluorobenzene to obtain a slightly gelatinous partial solution, which was chromatographed about 1/8 inch deep in a 0.45 μ glass fiber syringe filter (Watman, Motorcycles ™). Passed through a pad of silica gel. A portion of this solution was sent for ¹⁹ F NMR and it was found that the dissolved polymer composition was 50 mol% PMD and 50 mol% PDD. The remaining filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

A PMD: PDD solution was spin coated onto a CaF ₂ substrate to produce a polymer film 12762 mm thick. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between the absorbance (in reciprocal of microns) of the PMD: PDD versus the wavelength lambda (λ) in nm is shown as sample 34 in FIG. 17. 157 nm absorbance / micron was determined to be 0.404 / micron. 193 nm absorbance / micron was determined to be 0.006 / micron. 248 nm absorbance / micron was determined to be -0.002 / micron.

Example 30-PMD / VF2

To <75 ㎖ autoclave was cooled to -20 ℃ CF ₃ CFHCFHCF ₂ CF ₃ of from about _{0.17M DP 5㎖, CF 3 CFHCFHCF 2} CF 3 15㎖ and perfluoro (2-methylene-4-methyl-1,3 11.6 mL of Dioxolane) (PMD) was added. The autoclave was pressurized to 100 psi of nitrogen, vented 10 times, and additionally 9.6 g of vinylidene fluoride (VF 2) was added. Shaking overnight at room temperature gave a white solid. 23 g of resin was obtained by evaporation under nitrogen under pump vacuum for 16 hours and then in a 77 ° C. vacuum oven for 32 hours.

(C ₅ F ₈ O ₂ ) ₁ (C ₂ H ₂ F ₂ ) ₂ Theoretical value: 29.05% C, 1.08% H

Found: 28.71% C, 1.38% H

Solution Preparation:

1 g of poly (PMD / TFE) was rolled with 19 g of hexafluorobenzene to obtain a partial solution, which was passed through a chromatographic silica pad about 1/4 inch deep in a 0.45 μ glass fiber filter (Watman, Motorcycles ™). I was. A portion of this solution was sent for ¹⁹ F NMR and it was found that the dissolved polymer composition was 54 mol% PMD and 46 mol% vinylidene fluoride. The remaining filtrate was used to spin coat a thick film on the optical substrate for absorbance measurements.

Sample 11-PDD / CTFE

Poly (perfluorodimethyldioxol / chlorotrifluoroethylene) [poly (PDD / CTFE)] has been widely reported in the literature (eg US Pat. No. 4,754,009). The poly (PDD / CTFE) used here was prepared by aqueous emulsion polymerization.

Theoretical value of (C ₅ F ₈ O ₂ ) ₁₀ (C ₂ F ₃ Cl) ₂₃ : 22.52% C, 15.93% Cl

Found: 22.41% C, 15.94% Cl

Solution Preparation:

2.5 g of poly (PDD / CTFE) was rolled with 30 ml of hexafluorobenzene to produce a pale yellow solution, which was passed through a 0.45 μ glass fiber filter (Watman, Motorcycles ™). Since this solution is too viscous to be easily spin coated, 11.2 g of this solution was again diluted with 10.1 g of hexafluorobenzene. This diluted solution was used to spin coat a thick film on the optical substrate for absorbance measurements.

A 10:23 PDD: CTFE solution was spin coated onto a CaF ₂ substrate to prepare a polymer film having a thickness of 1903 mm 3. Absorbance / micron was then determined using VUV absorbance measurement.

The relationship between the absorbance of 10:23 PDD: CTFE (inverse of microns) versus wavelength lambda (λ) in nm is shown as sample 11 in FIG. 18. 157 nm absorbance / micron was determined to be 1.44 / micron. 193 nm absorbance / micron was determined to be 0.018 / micron. 248 nm absorbance / micron was determined to be 0.046 / micron.

Claims (36)

Perfluoro-2,2-dimethyl-1,3-dioxo or amorphous vinyl homopolymer of CX ₂ = CY ₂ , where X is F or CF ₃ and Y is H Vacuum ultraviolet (VUV) transparent showing absorbance / micron (A / μm) ≦ 1 at 140-186 nm wavelength including, 2-dimethyl-1,3-dioxol and CX ₂ = CY ₂ amorphous vinyl copolymer matter. The method of claim 1, wherein 0-25 mole% of at least one monomer CR ^a R ^b = CR ^c R ^d (where CR ^a R ^b = CR ^c R ^d enters the homopolymer or copolymer in a nearly random manner) ( Wherein R ^a , R ^b and R ^c are each independently selected from H or F, and R ^d is F, CF ₃ , OR _f , where R _f is C _n F _{2n + 1} and n is 1 to 3 VOH) and OH (when R ^c = H). The method of claim 1, wherein 40 to 60 mole percent of at least one monomer CR ^a R ^b = CR ^c R ^d (where CR ^a R ^b = CR ^c R ^d enters the homopolymer or copolymer in an almost alternating manner) ( Wherein R ^a , R ^b and R ^c are each independently selected from H or F, and R ^d is F, CF ₃ , OR _f , where R _f is C _n F _{2n + 1} and n is 1 to 3 VOH) and OH (when R ^c = H). CH ₂ = CHCF ₃ and CF ₂ = CF ₂ , CH ₂ = CFH and CF ₂ = CFCl, CH ₂ = CHF and CClH = CF ₂ having a monomer ratio of about 1: 2 to about 2: 1; Perfluoro (2-methylene-4-methyl-1,3-dioxolane) and perfluoro (2,2-dimethyl-1,3-diosol); Amorphous vinyl copolymers of perfluoro (2-methylene-4-methyl-1,3-dioxolane) and vinylidene fluoride in proportions providing an amorphous composition; And vacuum ultraviolet (VUV) transparent showing absorbance / micron (A / μm) ≦ 1 at 140-186 nm wavelength comprising a homopolymer of perfluoro (2-methylene-4-methyl-1,3-dioxolane) matter. The vacuum ultraviolet transparent material according to any one of claims 1 to 4, wherein A / micron <0.8 at a wavelength of 140-186 nm. The vacuum ultraviolet transparent material according to claim 5, wherein A / micron <0.2 at a wavelength of 150-160 nm. 7. A vacuum ultraviolet transparent material according to claim 6, wherein A / micron <0.1 at a wavelength of 155-159 nm. The vacuum ultraviolet transparent material according to claim 1, comprising a homopolymer of perfluoro-2,2-dimethyl-1,3-diosol. The vacuum ultraviolet transparent material of claim 8, wherein the homopolymer of perfluoro-2,2-dimethyl-1,3-diosol is present as a layer or film having a thickness in excess of 250 nm. The nose of claim 1 wherein perfluoro-2,2-dimethyl-1,3-dioxol and at least one monomer CX ₂ = CY ₂ , wherein X is F or CF ₃ and Y is H Vacuum ultraviolet transparent material comprising a polymer. The vacuum ultraviolet transparent material according to claim 10, wherein the copolymer is a copolymer of perfluoro-2,2-dimethyl-1,3-dioxol and vinylidene fluoride. 3. The polymer of claim 2 wherein the polymer is> 75 mole percent perfluoro-2,2-dimethyl-1,3-diosol and at least one monomer CR ^a R ^b = CR ^c R ^d , wherein R ^a , R ^b and R ^c are each independently selected from H or F, R ^d is F, CF ₃ , OR _f , where R _f is C _n F _{2n + 1} and n is 1 to 3, and OH ( Vacuum ultraviolet transparent material, which is an almost random copolymer consisting of a group selected from the group consisting of R ^c = H). 13. The vacuum ultraviolet transparent material according to claim 12, wherein the copolymer is> 75 mol% perfluoro-2,2-dimethyl-1,3-diosol and <25 mol% tetrafluoroethylene. 4. The polymer of claim 3, wherein the polymer is 40-60 mol% CX ₂ = CY ₂ , wherein X is F or CF ₃ and Y is H, and 60-40 mol% of monomers CR ^a R ^b = CR ^c R ^d (wherein R ^a , R ^b and R ^c are each independently selected from H or F, and R ^d is F, CF ₃ , OR _f (where R _f is C _n F _{2n + 1} , and n is 1 to 3) and OH (which is selected from the group consisting of R ^c = H)). The vacuum ultraviolet transparent material of claim 14, wherein the copolymer is a hexafluoroisobutylene / trifluoroethylene copolymer having a monomer molar ratio of about 60:40 to about 40:60. The vacuum ultraviolet transparent material of claim 14, wherein the copolymer is a hexafluoroisobutylene / vinyl fluoride copolymer having a monomer molar ratio of about 60:40 to about 40:60. The copolymer of claim 2 wherein the copolymer is> 75 mol% CX ₂ = CY ₂ , wherein X is F or CF ₃ and Y is H and <25 mol% monomer CR ^a R ^b = CR ^c R ^d (wherein R ^a , R ^b and R ^c are each independently selected from H or F, and R ^d is F, CF ₃ , OR _f (where R _f is C _n F _{2n + 1} , n is 1 To 3) and OH (when R ^c = H)), which is a nearly random copolymer of vacuum ultraviolet transparent material. 18. The vacuum ultraviolet transparent material of claim 17, wherein the copolymer is> 75 mol% vinylidene fluoride and <25 mol% hexafluoropropylene. The vacuum ultraviolet transparent material according to claim 14, wherein the copolymer is 60-40 mol% vinyl fluoride and 40-60 mol% chlorotrifluoroethylene. 5. A pellicle comprising the vacuum ultraviolet transparent material of claim 1. An anti-reflective coating comprising the vacuum ultraviolet transparent material of claim 1. An optically clear glue comprising the vacuum ultraviolet transparent material of claim 1. A light guide comprising the vacuum ultraviolet transparent material of claim 1. A resist comprising the vacuum ultraviolet transparent material of claim 1. The resist of claim 24 further comprising a dissolved reactive monomer. A transmissive optical element comprising the vacuum ultraviolet transparent material of claim 1. A copolymer composition comprising 40-60 mol% hexafluoroisobutylene and poly (hexafluoroisobutylene: trifluoroethylene) having 60-40 mol% trifluoroethylene. Amorphous copolymer composition comprising poly (hexafluoroisobutylene: vinyl fluoride) having 40-60 mole percent hexafluoroisobutylene and 60-40 mole percent vinyl fluoride. 29. The copolymer composition of claim 27 or 28 having A / micron <1 at 140-186 nm wavelength. The copolymer composition of claim 29 having A / micron <0.8 at a wavelength of 140-186 nm. 31. The copolymer composition of claim 30, having A / micron <0.2 at a wavelength of 150-186 nm. 32. The copolymer composition of claim 31, having A / micron <0.1 at a wavelength of 155-186 nm. a) placing the monomer (optionally diluted with solvent and / or initiator) in a position where film formation is desired, and b) initiating the polymerization by physical and / or chemical means Method of producing a PDD film having a thickness exceeding 250 nm comprising a. Use of the polymer of claim 18 as an adhesive. Use as an adhesive for attaching a pellicle to the photomask of the polymer of claim 18. Use as an adhesive for attaching a pellicle to the frame of the polymer of claim 18.