TWI249023B - Reference leak - Google Patents

Abstract

This invention relates to a reference leak. The reference leak includes a thin film which a tested gas could not penetrate through, and predetermined amounts of through holes formed there through. The through holes have predetermined sizes which are in nano magnitude. Because the shapes of the through holes are standard, the sizes and the amounts of the through holes are predetermined, so a leak rate of the reference leak of present invention could be calculated directly by a vacuum science classical theory, and it could attain a wider leak rate range than the prior art; even it could achieve an ultra-small leak rate.

Description

1249023 IX. Description of the Invention: [Technical Field] The present invention relates to a standard leak, and in particular to a through-type standard leak. [Prior Art] The standard leak is under a predetermined condition (inlet pressure is l〇〇kPa±5%, temperature is 23±7t), and the leak rate is a known leak for calibration. Standard leaky vacuum science and its application field A commonly used measuring instrument, especially the standard leaking hole, is the necessary relative measurement standard in the mass spectrometer leak detector which has been widely used at present. Hole periodic 氦 mass spectrometry

The most important parameter of the leak detector, the leak detection sensitivity, is calibrated to accurately give the magnitude of the leak rate of the system under test. Standard leaks have a constant leak rate. They are also called constant flow generators. They can usually be divided into two categories. The first type is a standard lead-type leak, such as platinum wire-glass non-matching standard leaks, metal flattening standards. Leakage; the second type is an infiltration type standard leak, such as a standard leak of quartz film. The National Technical Supervision Bureau has specially formulated the national measurement and determination procedures for JJG793-92 standard leaks. See Liu Xiulin in the literature "Aviation Measurement Technology" Vol. 21, No. 5, 43-45 (2001) ''Standard Leakage and Its Freshness' - Wen, the use of the Lin - Lai non-match fresh fox, leak The rate range is generally 1〇·6~1〇_8 托·liter/second, which is a type of twisted wire with a diameter of 〇·1~〇·15mm and 11# hard glass for non-matching. The leakage coefficient obtained by different expansion coefficients of the material is difficult to artificially control the size and number of the fresh leak holes in the manufacturing process towel, and the leak rate is poorly controlled/the drunk must be calibrated by other equipment to determine , can not self-calibration; ^ degree will cause the material to expand and contract, so it is susceptible to temperature changes, the stability of the leak rate and the narrow range of leakage rate, it is difficult to achieve a smaller leakage rate measurement. Flat type standard leak, the leakage rate is generally 1〇n, the straight copper wire or the kovar (four) turn clock money is difficult to produce, so the size of the standard leak hole in the manufacturing process is difficult to control, the leak rate must be It can be determined by other equipments, and it can not be self-calibrated. Difficult to achieve a finer detection of the leak rate of the multi-range -. MG- ^ implanted as liters / sec., Prepared using the calibrated leak 'normalized face of the quartz tube blow molding of various diameters and thickness of the film ball 7

1249023 Bubble 'use of quartz can only make the system pass, and its money leaks" because the film bulb is blown, so the standard of the film bulb is difficult to control the 'through hole size is difficult to obtain, so Manufacture solution = pass: It leaks, it can be calibrated by other equipment: The leak rate range is narrow, it is difficult to achieve a smaller leak rate inspection, and it is suitable for helium, which limits its application range. . 1 'Ya' 'Shiyang Lai standard leaks only as mentioned above' The standard leaks currently used such as the surface wire _ glass flat standard secret, Shi Helin Lai, because the words must be borrowed from the 仃 calibration (see Wan Zhaozhi , Ye Sheng and others in the literature "真 ^

No. 2, 39-41 (2002) t W t W "Self-calibration; the leak rate range is narrow, making it difficult to detect smaller leak rates. There are Li Yu ^ ‘It is necessary to provide a standard leak, which can self-calibration, rate detection and so on. _ SUMMARY OF THE INVENTION In order to solve the problem that the standard leak leak rate in the prior art must be calibrated by other equipment, and it is difficult to detect a smaller leak rate, the object of the present invention is to provide a self-sufficient and small leak. The rate of detection of standard leaks. For the purpose of the present invention, the present invention provides a standard leak which includes a film impermeable to a gas to be measured and a predetermined number of through holes formed in the film, the through holes having a pore size. Preferably, the through hole aperture size ranges from nanometer. More preferably, the through hole has a pore size ranging from 10 nm to 500 nm. Preferably, the leak rate of the standard leak hole satisfies the formula ···································· 1 is the pressure of the inflow end of the measured gas of the standard leak hole, P2 is the pressure of the outflow end of the measured gas of the standard leak hole, and the air conductance of the single pass hole of Y and the formula, which satisfies the formula: Y=12·1xV^7x (D3/ L) (l > 20D), in Guangcheng, Μ is the molecular weight of the gas to be measured, D is the diameter of the through hole, and L is the length of the through hole. The standard through-hole leakage rate of the standard leak is 1 (Γι5~1 (Γ8 Torr·sec. sec. 1249023) The material of the film includes metal material, ceramic and glass. The standard leak hole can be used for helium gas. Metering of air, oxygen and nitrogen. The shape of the through hole includes a cylindrical shape and a polygonal shape. Compared with the standard leakage provided by the prior art, the number and size of the through hole can be processed by the nanometer. The technology does (4) obtain, and then, by the formula: Q = nx (p | _ (5) X YJ, Q 4 standard leak leakage rate, coffee) is the number of through holes §, R is the standard leak measured Gas pressure at the end of the muscle, p2 is the measured gas of the standard leak hole · i terminal pressure ^ (Dj / L) (Μ is the molecular weight of the gas in the through hole ' D is the diameter of the through hole, L is the length of the through hole) The leak rate of the standard leak can be calculated. When the two cranes are in the range of 1/3)1) and G2qd (in the formula, the gas gas free path), the calculation accuracy is 5%. To achieve self-calibration, and a wide range of leak rates, the detection of ultra-small leak rate can be achieved. [Embodiment] The present invention will be further described in detail below with reference to the accompanying drawings. See the sixth figure, the fresh leak hole 丨 (8) provided by the present ride includes a film 30 for preventing penetration of the gas to be measured, and a predetermined number of through holes 3G1 formed in the film 3〇; the through hole 3Q1 has a predetermined The size of the pore size is selected to be nanometer (i.e., smaller than 丨_); the pore size of the through hole is more preferably IGnm 〜5_m. The fresh leak hole 100 can be used to measure the quasi-standard of the mass spectrometer leak detector, the measurement of the micro vacuum pumping speed, the scientific research of the gas-time surface, and the provision of small flow. For the film 30, the material may be a metal material, glass, ceramics or the like; the choice of the material determines the type of gas suitable for the standard leak hole 1 最终 which is finally formed. If you choose metal materials, you can use 'air alcohol' because helium cannot penetrate metal materials: if you choose glass or ceramics, it can be used for air, oxygen, argon leak rate measurement, because air, oxygen , argon gas, etc. can not penetrate glass and ceramics. / Referring to the first to fifth figures, the standard leak provided by the present invention can be realized by a pattern transfer technique using a predetermined size and number of nanowires as a template, which comprises the following steps: First, providing a clean The substrate 1 may have a crystal orientation of <U1>, <1〇〇>, <u〇>, or other crystal orientation; in this embodiment, it is preferably <111> crystal orientation, i.e., Si<; iii >; Second, a catalyst film is formed on the ruthenium substrate 1 , and the material of the catalyst film may be gold, iron, cobalt, silver, etc. 'In this embodiment, the gold film 2 is used as a catalyst; the thickness of the gold film 2 is 1249023 The range of 0. 2 nm to 10 nm, preferably 1 nm; wherein the gold film 2 is formed by evaporation, sputtering or electroplating, etc., and then formed on the gold film 2 by photolithography or electron beam etching. a pattern structure 21 of a number and size, and the size of the pattern structure 21 is less than 1 μm so that only one nanowire is grown on the single pattern structure 21; or a predetermined size can be directly formed on the base substrate by a printing technique and Arranged pattern structure 21 The film 2; wherein, the specific shape of the pattern structure 21 may be a minute square and a deformed structure thereof; secondly, the substrate having the gold thin tantalum 2 formed thereon is placed in a CVD reaction chamber (not shown) The CVD reaction chamber provides the gas-containing material in the gas phase. In this embodiment, the gas of SiQ4 is used; the concentration of the gas of the gasification of the gas is controlled, and the temperature in the reaction chamber of the CV] is controlled at 700. C ~ 900 ° C, under the catalysis of the above gold film 2, in the position of the pattern structure will grow -Vanami structure 'such as nanowires, nanorods; in this reality, the tree base magic grows out of Shi Xi The rice line 1 is the structure of Chenxian County; the rice noodle is returned to the direction of ηι>, that is, the size of the hole perpendicular to the stone in the Xixi 氐 中 中 夕 示 示 示 示 优选 优选 优选 优选 优选 优选 优选 优选 优选 优选 优选 优选 优选 , 夕 夕The length of the nanowire 11 is dry Ml_n~1G_; the diameter and length of the specific rice noodle u can be controlled by controlling the size of the pattern in the thin gold sheet, the growth temperature of the venetian structure, the concentration of the growth atmosphere, and the growth day In the case where the size of the pattern structure 21 is not greater than 丨_, it can be controlled by _ Conditions are such that the number of revolutions equal to the number u noodle of 21 m wire diameter Η pattern structure, the thickness of the gold film by a length of 2, the growth temperature, and the concentration of the growth atmosphere with money, time-controlled conditions. Alternatively, the rice noodle n can be oxidized to the dioxide Komi line according to the subsequent n. In order to ensure that the results of the calculation of the city 拙 拙 拙 拙 , , , , , , , , , , , 要求 要求 要求 要求 要求 11 11 11 11 11 11 11 11 Fourth, the second film layer is deposited on the substrate 丨 of the growth god nano line u, and the second film layer is made of metal material, glass, and ton; the choice of material determines the final standard leakage gas. Type, if metal material is selected, it can be applied to the leakage rate measurement of nitrogen, because it is transparent to metal; if it is selected to be thrown or shouted, it can be applied to air, oxygen, and complex:::2, because of empty rolling, oxygen , argon gas, etc. can not penetrate glass and ceramics; this embodiment: t ίΐί layer 3, such as nickel, etc., the thickness of its deposition can be adjusted according to the needs of the 矽 nanometer 2 二 二 ί ί ί ' ' ' ' ' ' ' After the completion of the metal film layer 3, mechanical or electrochemical polishing of the first temple can be used to make the metal _3 on the surface of the table, remove the outcrop material scale u end, 10 1249023 on the Shi Xi Nai line 11 diameter 20 according to the schedule The material of the leaky paste is kept at a small time; ', η and = bottom H anti-linking (Reatlve lQn EtGhlng, _ go_nano line Erxi base 1 material without damaging the metal film layer 3 'Therefore, the size of the metal film layer 3 is formed by the second half of the tN=2 (where the through hole 31 is perpendicular to the base 1) Plane); due to the use of the reaction from the metal film shore 3 large nanowire U and Shi Xi base 1 material, without damaging the stone Xi Nian line 11 around the stone eve stone show that the line is completely off; therefore The aperture size of the through hole 31 and the length of the through hole & and the thickness of the final metal film layer 3, the through hole

Dry), the number of lines U is equal; and thus a makeup 拠, such as the fifth circle V i, rt, the predetermined size aperture and number. Of course, you can also _ wet legal duties (such as, Qian ^ Temple Corruption) or plasma engraved guardian to go when the nanowire u and Dedi i materials, but do not know 'injury metal film layer 3; or according to different nai The material of the rice noodle material and the second film layer are selected to be appropriately removed. In the production process of the above-mentioned standard leak hole, if other stone-like bases are used, the growth of the non-rice line and the base plane are at an appropriate angle; correspondingly, the standard leak hole is made. The hole is also at an angle to the substrate; the size and number of the apertures of the through hole are still determined by the size and number of the diameter of the rice noodle. The calculation of the standard leak leak rate provided by the present invention will be specifically described below. The standard leak hole 10 formed as above has a standard size (cylindrical shape) of the through hole 31, the size and the number are known, and the pore size is up to the nanometer level; therefore, it can be directly obtained by the classical theoretical calculation of vacuum science. Leakage rate value. For example, the pressure is atmospheric pressure, and the mean free path λ > 5 () ηιη; the pressure is i to the nitrogen gas, and the mean free path λ > 38 ηιπ. Under the condition that A > (1/3) D is satisfied, the gas flow guide of the standard leak provided by the present invention can be calculated by the Knusen formula. For a single through hole of diameter D, length 匕, and L-20D, in 2 (rc condition, according to the Knusen formula, the flow of helium (in steady state, the flow flux of the through hole under unit pressure difference) Satisfaction: Y=12· 1xV29m7x(D3/L)......(1) In formula (1), Y is the conductance of a single through-hole helium gas, the unit is liter/second river “); Μ is the helium in the through hole Molecular weight, Μ 2 4 ; D is the diameter of the through hole, the unit is centimeter (cm); 11 1249023 L is the length of the through hole, the unit is centimeter (cm). For any temperature condition, the correction of formula (1) is: (4) · lxV^xV77^x (D3/L) (2) In equation (2), T is the absolute temperature value in Kelvin (κ). Moreover, the helium flow through the standard leak per unit time, ie the standard leak The leak rate of the hole satisfies: Qi=nx(Prρ2) χγ (3) In equation (3), Qi is the leakage rate of the standard leak, the unit is Torr· η; η is the number of through holes in the standard leak, And the number of tickets (η-ι);

Pi is the pressure at the inflow end of the measured gas in the standard leak hole, and the unit is the support (T〇rr); P2 is the dust intensity of the measured gas outflow end of the quasi-leakage hole, and the unit is the support. Therefore, when the through hole diameter D is 100 nm, the length L is 5/zm, PF760TOIT, PH), the number of through holes is n=l, and the temperature is 2 (TC, it is known from the formula (1) and the formula (3) that the single pass The airflow of the hole is guided by Y 12. lxV29/4x((l〇)/(5x10 4))=6. 51xl (TuL/s, the leakage rate of the standard leak hole q=(76〇-〇) x6· 51x10 u= 4.95xl (T8Torr.L / s; fPelTorr, the standard leak provided by the present invention can achieve 1 (T15 Toit. L / s leak rate. When the number of s through holes η is 1000, then from equation (3), The leak rate of the standard leak hole is correspondingly 1 times that of η = 1. In another embodiment, a metal film is deposited on the ruthenium substrate, and a cylindrical shape is carved on the metal film by a focused ion beam direct writing technique. The aperture of the through hole and the through hole is generally above 1 〇 nm; then a standard leak is obtained by removing the ruthenium substrate near the through hole by using the necessary etching technique. The standard leak provided by the present invention is changed by The material of the second film layer is changed to the oxidized slag of the i-type material suitable for helium, and the standard leak hole suitable for air, oxygen and argon can be obtained. When the leak rate is calculated, the formula is changed accordingly. 1) and the formula (the imaginary value is sufficient. In addition, the shape of the through hole of the standard leak hole described above is cylindrical, and it may be other shapes as long as it does not deviate from the effect of the present invention. The shape may be a polygon, but for the flow-through juice formula (〇 and (2), the corresponding shape correction factor needs to be considered. In addition, other variations may be made by those skilled in the art within the spirit of the invention, such as using other materials or other The method is to make a standard leak hole design, etc., as long as the standard leak hole produced has the pre-size and number; the self-calibration can be realized. 12 1249023 In summary, the invention has indeed met the requirements of the invention patent, and the patent application is filed according to law. However, the above is only a comparative example of the present invention. For those who are familiar with the art of the present invention, the equivalent modification or variation of the invention in the case of the aid of the present invention is included in the application of the town [simplified description] The first figure is a schematic diagram of a crucible substrate according to an embodiment of the present invention. The first figure is a schematic diagram of forming a catalyst film on the substrate of the Shixi. The third figure is a structure of a vitamin nanostructure grown on the substrate. FIG.

The fourth figure is a schematic diagram of forming a second film layer on a substrate on which a one-dimensional nanostructure is grown. The fifth figure is a schematic view showing the structure of removing the one-dimensional nanostructure and the base material. .第六 The sixth figure is a schematic cross-sectional view of a standard leak according to the present invention. [Main component symbol description] 矽 base 1 standard leak hole standard leak hole 100 矽 nano line gold film 2 pattern structure metal film layer 3 film through hole 31 through hole 10 11 21 30 301

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Claims (1)

1249023 X. Patent application scope: 1. A standard leak hole comprising: a film impermeable to a gas to be measured; and a predetermined number of through holes formed in the film, the through holes having a predetermined size aperture. 2. The standard leak as described in the scope of claim 2 is improved in that the material of the film comprises a metal material, glass and ceramic. 3. The improvement of the fresh leak as described in the section of the special fiber is that the shape of the through hole includes a cylindrical shape and a polygonal shape. 4. The standard leak as described in the application of the first item U, the improvement is that the diameter of the through hole is nanometer. 5. The method of applying the special fresh hole according to item 4 of the item m is improved in that the diameter of the through hole is in the range of 10 nm to 500 nm. 6. The standard leak according to claim 1, wherein the leak rate of the single through hole of the standard hole is 1 〇 15 to 10 · 8 Torr / sec. 7. The standard leak as described in claim 1 is improved in that the length of the through hole is not less than 20 times the aperture size of the through hole. 8. The standard leak as described in claim 7 is improved in that the leakage rate of the standard leak is such that: Q = nx (PrP2) χΥ, where Q is the leak rate of the standard leak, η (η^1) is the number of through holes in the standard leak hole? 1 is the pressure at the inflow end of the measured gas of the leak hole, ρ2 is the pressure at the outflow end of the gas to be measured of the leak hole, and Υ is the air conductance of the earlier 'one through hole' which satisfies the formula: Υ=12· \χ4Ϊ9ΙΜ x(D3/L) Where Μ is the molecular weight of the gas to be measured, D is the diameter of the through hole, and l is the length of the through hole. 14