MXPA97006656A - Apparatus for depositing a barrier film on three-dimensional articles - Google Patents

Abstract

The present invention relates to an apparatus capable of applying a coating of chemical barrier film deposited as plasma-assisted vapor to the external wall surfaces of two or more three-dimensional articles, the apparatus comprising: a vacuum-sealed chamber; to supply a monomer to the articles, a means to supply an oxidant to the articles, a means for inserting electrodes with radiofrequency energy into the internal surface of the articles, at least two electrodes, a means for creating and maintaining a vacuum inside. of the chamber containing the articles, a means for containing the above elements in the vacuum-sealed chamber, and also where the apparatus is mounted on a pumping station, and wherein the chamber is subject to a means for introducing energy into the chamber. the articles, where the medium is a radio frequency voltage generator

Description

DEVICE FOR DEPOSITING A BARRIER FILM ON THREE-DIMENSIONAL ARTICLES FIELD OF THE INVENTION The invention relates to an apparatus for use in a PGO PSO Deposition in the Chemical Vapor Phase I nc reheating to Plánraa ÍPECVD) where an F'svs.t he tried matepal inory _ m was deposited in tri-dimensional articles, "including low-temperature fusion article. The coating has e; cel ets barrier projects against gas and / or water vapor. BACKGROUND OF THE INVENTION With the recent emphasis on the use of medical-plastic products, UIH n cesi a e-o ct l to improve the barrier pro ad es d- > Articles produced for medical products that were used to improve their barrier properties include, but are not limited to, collection tubes, and par- ticularly those used in the recovery of blood, Adi ci At the same time, such improvement of the barrier properties of articles made with polymers can be applied in food, cosmetics, etc.

As for, for example, 3 recirculation tubes, the collection tubes will require certain performance standards to be used in medical applications. Such performance standards include the ability to maintain a volume of extraction greater than approximately 90% of the original volume within a period of one year, this power can be achieved by radiation and not interfere with tests and analyzes. Therefore, e. iste the need to improve 1 s _ • barrier properties of articles made with polymers and especially plastic blood collection tubes where it could meet certain performance standards \ v? l ai tículo would be effective and could be used wi _p n. ac edions. Pe { what if the glass or well of or; Metallized or synthesized by chemical vapor deposition techniques have been used as thin barrier coatings in polypropylene films. However, thin glass-like synthesized films are substantially granular in terms of their mole instead of being substantially glass-like in a continuous manner and therefore do not have the water vapor and oxygen barrier characteristics that They characterize a truly continuous glass material. It has been shown that to overcome the drawbacks of the morphology of the thin glass-like films, layers of glass-like films can be "stacked" with an organic polymer film with interposed between each layer. Such multilayer layered coatings increase the barrier performance to o; However, the formation of layers does not produce a glass-like barrier and the layered formation simply acts as a laminate of polymeric films and polymer revelations. au > 'i3atp. It is therefore desirable to produce a compound which can be used to achieve a satisfactory performance. barrier = t 1 water and a) similar gas r 33 vi rio. In general, the pro-ers; ? stertte = > _t? ? .- mplean for the production ele pol i the 3 s of barriers d > Are PECV'D suitable for my "1 pa 1 in t>? To super i ie bt" - | unen »e 3, -, = 5 that has been unrolled? they are not very useful for their use in the treatment of alpha-density of ca.sub.ga.The process of the intended intention is appropriate for such an incidental use.DECENDIUM OF THE INVENTION The present invention relates to a apiatrate and process for applying a barrier film deposited in plasma chemical-assisted vapor phase on top of the outer walls and two or more articles, for the purpose of example. hollow articles. ", comprising: a) providing an apparatus capable of applying said reams of barrier film on the walls of said articles, said apparatus having: a hermetic chamber, a device for supplying a monomer to said articles; 1, which is a device for supplying such articles; a device for inserting voltage-activated electrodes of the radiofrequency type into the internal surface of said art. 5 at least two elec- trodes; a device for croaking and maintaining a vacuum within said box containing said articles; and also < r < - > wherein said apparatus is mounted in a pumping station, and wherein said unit is subjected to a device for supplying energy within said article where said device is a voltage generator of the same type. iofre uencia; b) pos 1 ion. At least two idimensional articles having an open surface, a closed wall, an outer wall, an inner wall, an outer wall surface and an inner wall surface such that said open open paddle is placed on said at least one item; c > emptying said chamber containing said articles at less than T > Torr; d) supply a mono gas 1 co to what has = > uperf ies ex t rnas of said article from a little to 1 with 5 s > tm and of a roxi admente 80 inT rr a! _, < "InTor'-je) to provide a s = - oxidant to said e x ternal surfaces of approximately 150 sccm and approximately 80 mTorr to 160 mTorr; f) to supply a voltage of the radio type with respect to said electrodes of approximately 1 to 50 HHz and approximately 0.1 to 2 m ts ts cm2, and g) obtain barrier film coatings in said gun at a velocity of 40 to 100 nm / min BRIEF DESCRIPTION OF THE DI BU TOS Figure i is a schematic view 1 c: a of a time of the present invention 1. Figure -3-b is a graphical representation of the permeation of pol ie 1 coated reindeer as a function of pressure f Torr) V &G ZV flux of o: igena < S > ~? TI) during depo i to p 13 sm. Figure 7 is a three-dimensional representation of a modality where 10 electrodes are found and the electrode electrode is present, and this electrode matrix is used in the apparatus of FIG. 1. DETAILED DETAILED THE INVENTION The present invention focuses on a apiarate for its use in a PECVD process where a revelation of inorganic material can be placed in three-dimensional articles in a closely spaced mat. This inorganic material can be a metallic oxide as for example Si where s is approximately 1..3 ap r ately 2.5; or a composition based on or: aluminum. The oxide or silicon-based composition is substantially dense and impervious to vapors and is preferably derived from volatile organics and a solvent such as oxigen or oxygen. well nitrous oxide. Preferably, the thickness of the material based on silicon oxide is appropriate. imadamente 5 4oft nm. Figure 1 shows an outline of an apparatus 40 in relation to a modality of the invention. In use, the polymer tubes are placed on the electrodes 43 and the chamber 44 is evacuated to a base pressure, preferably less than 5 mTorr. An orgasm vapor (blunt for example HfDSO (he: amildildyl: "i? O"> an o?? D "nte f > pmo for example oxygen) are admitted in the apparatus pur 41 and '12, respectively For an air system: just 30 centimeters (12 inches) in diameter with vertical flow, a flow of HMDSO of apiro, immaculately 1 to 5 sccm and an oxygen flow is used. Approximately 50 to 150 sccm The system is pumped with only one speed to maintain a pressure of approximately 80 to 160 mTorr The device is mounted on a pumping station 46 = A radio frequency type voltage generator Rp- <uence and the corresponding system 45 are used to generate a plasma with a frequency of apiro: imadamente 3 to 50 MH and a power for elective area with apiro- imately Ol 2 (? iatts / cm2 according to the number and the proximity of the electrodes.A deposit of S? O; < acts in this manner on the exposed article at a speed of the order of 40 to 10 0 nm / min Barrier ignition properties can be achieved with a thickness of 50 to 400 n. During deposition, the electrode potencies oscillate with an amplitude of approximation t 50 v to 1000 v peak to peak for frequencies d * = >; RF of apro; imad-iment 5 to 15 MH .. For a given PF energy 1 _ s amplitudes decrease with increasing frequency and are reinforced by a frequency inu ión ion. If the corresponding network includes a blocking layer and a part of the electrode circuit is attached to the plasma, a current from the plasma coming from the plasma establishes a negative DC ion on the electrodes of appropriateness. -100 goes ~ -4? v. This polarization can be eliminated or it can be eliminated essentially by means of the microtome in the area of the electrode circuit by the plasma and / or by the short-circuit elimination of the DC component of the electrode potential. through an inductor that blocks the RF current. The optimum barrier is obtained under eleposition conditions that supply an element of energy to the polymer article without reaching c.a.ni, a. r a thermal degradation. This absorbed energy is a product of the voltage, ion current, and electrical potential in the plasma sheath that accelerates these ions. Since the process is carried out in a vacuum, a conduction or convection d_-heat is observed and > -ace? all the energy absorbed is? Hold »To produce > i I? A barrier film high > . At the same time, for example, a SiOx barrier film, a narrow range of cracks and chemical properties must be met. The failure to comply with any of these types of properties results in a highly permeable film. The graphs surfaces of? The response of the oxygen barrier properties against the plasma deposition process parameters (see Figure 2) show that the optimum barrier is only ob ected in a small a in a matrix space for flow rates. geno and HHD5Ü and system pressure. Outside this range, simile films are obtained. - To soft polymers in house of excess of monomers, highly tense and fractured films are obtained in case of excess of oxygen, slow rates of deposition occur in case of ba under pressure, and a gaseous nucleus occurs that causes dust deposits in a "high system" scenario with adequate chemical con junctions, a poor barrier will be obtained without the adequate ion bombardment of the material during deposition. The electric field near the substrate surface is essential to attain speed at the deposition and most importantly to identify the film by sputtering to eliminate the rounds and structure granules. Excessive ionic can thermally destroy film 13. The equilibrium of these factors requires an adequate combination of the total number of electrodes, -paces between electrodes, frequency PF, energy PF, and plasma coupling to a conductor connected to ground. L -: RF energy supplied to an electrode simul- taneously generates the PF stacks discharge surrounding the polymer article and produces an electric field that accelerates the ions to 13 l at surface. The discharge causes l f r ^ > It is reactive, which can not be relied on in the film.The electric field densifies independently of the material deposited in the impermeable film, there is no security for a given geometry of the film. Both processes can be carried out simultaneously, there are examples in which no barrier can be achieved during the process space.The discharge formed around an electrode is at an intense distance of approximately 0. , 25 to 2 cm and decreases in density by 3 greater distances.When additional electrodes are arranged in a matrix cn spacing of a few cm or less, as for example in re 0.5 to 15 cm, these discharge areas are spliced and the The plasma density of a given electrode is increased by the effect of its neighbors.This allows a lower PF energy to be used to achieve a given plasma density that can be needed.; ^ r r the chemistry of the reaction required. As mentioned above, the potential of electrode that with role 3 pod fields epen of RF energy and frequency. The potential of the plasma is influenced by the previous fa and before the flow of charged species has > ~? to any nearby conductive surface, such as an earthed cam wall. Po > - consequently, a system; I toso requires a carefully balanced set of parameters and process as well as a meth. The invention can be applied in various shapes according to the size of the articles to be coated. In the case of small indistinct circuits, the following configuration is a preferred configuration that can be used in the apparatus of Figure 1. 10 electrodes that fit inside PET tubes of 13; 1 OO mm are arranged in a matrix as shown in figure 3. The electrodes have location numbers 1-10. the separation distance from center to center in this case is 4 m but it is not limited to any. way to the distance. A flow of 2. _t_cm of HID1D50 and 70 sccm of oxygen is established and the pyrosion is regulated to l ?? Torr by regulating the pump. A deposit of SiO of 3 minutes is produced with an explosion of PF of 120 matts, 11.9 MHz. The electrodes are subjected to an amplitude of 770 v pr-p RF with a DC polarization of -230 v. Since these tubes have a surface area of approximately 40 cm2, this results in an energy charge of 0.3? N / cm2. This treatment provides an improved barrier to g-js and steam-water approximately 3 times higher than in the case of a 1 mm thick PET tube not t r t. None of the parameters mentioned above are independent of each other. For example, less numerous electrodes or more scattered ct requires a higher energy per area to produce the barrier: for example in the case of only four tubes used in the outer corners of the matrix; It is necessary to go, the electrodes No. 2, 3, 8 and 9 in Figure 3, since 13 energy is increased to produce a suitable plasma density, a thermal degradation is observed before achieving a comparable barrier. In this case, an electrode amplitude of 915 v p-p can not match the deposition produced with the 10-electrode arrangement of 770 v p-p. In addition, it has been shown here that the DC polarization has been extensively discussed in the literature on deposition of PECVD film media or for example in Sibson, Mat. Res. Soc. Sy p.Proc., 223 (199.). ) and Breen, Mat ,.

Res. Soc. Sy p. Prac. l5 (1990) as an essential factor for ion bombardment, it is irrelevant: by connecting the electrode circuit to an SOOO μH inductor with short circuit to ground, this polari ain can be totally reduced to zero without loss the barrier. By inserting resistors in series with the inductor, this polarization can be reduced stepwise. As this occurs, the potential of the plasma becomes positive, and the surface charge on the substrate is maintained to maintain the potential of the sheath. EXAMPLES FIEMEl OR T Using the arrangement of the preferred modality, pr H IJ? a year with flows of ga_, pressure and frequency of PF and if t niza i n identical, but with an energy of 1 R watts during 2 minutes. This treatment provided a narrator to the water approximately 2.5 times greater than that of the t > > bo in trat r. EXAMPLE II Another example is a treatment identical to the previous one except pf; a system was set to 16"t wa s during t minute, and a mt-jorta to l - './ re n c? > anJ i ta to sweep to 1 u.

Claims (5)

1. REI INDICATIONS 1. An apparatus capable of applying a chemical barrier film coating deposited in vapor phase assisted by p > On the surfaces and wall panels of two or more three-dimensional articles, said apparatus comprises: a vacuum-sealed chamber; a par-3 device to supply a monomer to cells; a device for supplying an item to said articles; a device for inserting electrodes with radio frequency energy within the internal surface of said a r t J c u 1 > > - •,; al? n? nu_ dos l t o s; a device to create- maintain- a vacuum within said chamber containing said articles; a device for containing the above elements in said vacuum sealed chamber; and further where said apparatus is mounted on a pumping station; and wherein said chamber is attached to a device for introducing energy into said articles where said device is a < -? r ad »> r type of voltage tension.
2. 2. The apparatus of claim 1 wherein said vacuum chamber is close to a plasma discharge generated around the "electrodes" and "im ¬ straints" or "bi" where said vacuum chamber is located. a surface connected to ground
3. 3. The apparatus of claim 1 wherein said apparatus has at least 10 electrodes and a device for carrying said electrode
4. 4. The apparatus of claim 1 wherein said apparatus it has at least 20 electrodes and a device for supporting the telescopes
5. 5. The apparatus of claim 3 wherein said electrodes are spaced at a distance of approximately 15 m. claim 4 wherein said electrodes are spaced apart apm, immaculately 0.5 to 15 Lili.