TWI253961B - Cleaning device applicable in cleaning solution circulation system and capable of prolonging lifespan of filter - Google Patents

Abstract

The present invention provides a cleaning device applicable in a cleaning solution circulation system and capable of prolonging the lifespan of a filter. The invented cleaning device is installed in a cleaning solution circulation system and includes a second storage tank, which contains a mixture solution of hydrofluoric acid, hydrogen peroxide, and hydrochloric acid, and is connected to two control valves on the cleaning solution circulation system through a pipeline. A second pump is used to circulate the mixture solution stored in the second storage tank through the pipeline and a filter in the cleaning solution circulation system in order to effectively clean the filter. The structural design according to the invention can effectively prolong the lifespan of the filter in a cleaning circulation system, while increasing the cleaning effect of the system.

Description

1253961 V. INSTRUCTION DESCRIPTION OF THE INVENTION (1) Technical Field The present invention relates to a technique for improving the life of a filter for a semiconductor integrated circuit cleaning process, and more particularly to an extended filter for use in a cleaning liquid circulation system Life cleaning device. [Prior Art] In the sub-micron wafer process, whether it is thin film deposition, high-temperature furnace tube diffusion, oxidation or wafer surface treatment after etching, it is necessary to go through many high-purity chemical cleaning processes, and then ultra-pure The water is washed to the final step of drying with isopropyl alcohol in addition to water. Semiconductor cleaning is mainly based on multi-tank cleaning. The American Radio Company (RCA) cleaning formula, which has been developed since the early 1960s, has been in use ever since, although various applications have been continuously developed in various modules. Only minor adjustments have been made to the ratio of chemicals and the order of cleaning. The RC A cleaning process mainly consists of three steps: 1. H 2S 0 4+ H 20 2 (SPM), which is a caroic acid formed by using sulfuric acid and hydrogen peroxide. Its strong oxidizing and dehydrating properties can destroy organic matter. Hydrocarbon bonding, the main purpose is to remove the photoresist. 2, ΝΗ40Η + Η 20 2+Η20 (ΑΡΜ, also known as SC-1 or ΗΑ), which uses the weakly alkaline action of ammonium hydroxide to activate the surface of the wafer and the microparticles, so that the surface of the wafer and the microparticles are mutually exclusive. For the purpose of cleaning, hydrogen peroxide can also oxidize the surface of the crucible wafer, and the effect of removing microparticles by micro-etching of ceria by hydrogen peroxide; the purpose of this cleaning step is to remove organic pollution and particles 3 HC1 + H 20 2+H20 (HPM, also known as SC-2 or HB), which utilizes peroxidation

1253961 V. INSTRUCTIONS (2) The metal contaminated with hydrogen hydroxide is dissolved by the formation of soluble gasification by hydrochloric acid and metal ions. Therefore, the purpose of this washing step is to remove metal contamination. The cleaning process of the cleaning process is carried out in a circulating manner and filtered by a filter to remove impurities or contamination in the cleaning solution. However, as component integration increases, the requirements of the Semiconductor Industry Association (SIA) for wafer quality, such as residual metals, negative (cationic) ions, oxygen, organic matter, and fine particles, are gradually increasing. The frequency of replacement of the filters used in the circulation system is thus also increased. The cleaning method and device for the transition device have been found in the previous case of China Patent Publication No. 4 2 9 1 7 3, which uses a pressure control device and uses a ring cap, a backstop, a backstop, a filter, etc. A filter system is formed for cleaning work. However, the structure of the previous case is complicated, and the solution composition in the tank or the pipeline is not described, and the cleaning effect is very limited. In view of the above, the present invention proposes a cleaning device which can be used in the cleaning liquid circulation system to extend the life of the device to extend the life of the filter and to improve the cleaning effect. SUMMARY OF THE INVENTION The main object of the present invention is to provide a cleaning device for extending the life of a filter in a cleaning liquid circulation system, which is further provided with a cleaning device on the cleaning liquid circulation system, with hydrofluoric acid and peroxidation. A mixture of hydrogen and hydrochloric acid to clean the filter to effectively remove particles of cerium oxide, cerium and its compounds, metals and their compounds, organic types, etc., and thereby obtain a better cleaning effect, thereby prolonging the service life of the filter . Another object of the present invention is to achieve a prolonged filter life and improved cleaning efficiency in an SC-1 cleaning cycle system using a simple structural design.

1253961 V. Description of invention (3) The effect of the fruit. In order to achieve the above object, the present invention further comprises a cleaning device in a cleaning liquid circulation system, the cleaning device comprising a second receiving groove, wherein a mixture of hydrofluoric acid, hydrogen peroxide and hydrochloric acid is installed therein. The second accommodating tank is installed on the two control valves of the cleaning liquid circulation system by using a pipeline connection, and the second mixture pump is used to flow and circulate the mixture in the second accommodating tank through the cleaning. A filter in the liquid circulation system to effectively clean the filter. The purpose, technical contents, features, and effects achieved by the present invention will become more apparent from the detailed description of the embodiments and the accompanying drawings. [Embodiment] The present invention further adds a cleaning device to a cleaning liquid circulation system, and uses the mixture of hydrofluoric acid, hydrogen peroxide and hydrochloric acid in the cleaning device to clean the filter to effectively remove the cerium oxide. Particles or impurities of ruthenium and its compounds, metals and their compounds, organic types, and the like. Referring to the first figure, a schematic diagram of a cleaning device is further disposed on the cleaning liquid circulation system for the semiconductor integrated circuit RCA cleaning process. The cleaning liquid circulation system includes a first receiving groove 10, A mixture of ammonium hydroxide (NH4OH), hydrogen peroxide (Η2〇2> and ultrapure water (D·I. water) (SC-1) is placed in the interior for use as a cleaning solution; 1 2 is connected to a heater 1 4, a first control valve 16 , a filter 18 , a second control valve 20 and a first pump 2 2 to form a circulation of the cleaning liquid. a circuit to utilize the first pump 2 2 to make the first receiving groove

1253961 V. INSTRUCTION OF THE INVENTION (4) The cleaning liquid in the 10 is flow-circulated and the impurities of the cleaning liquid, such as the stone, the sulphur dioxide, the metal, the organic matter, the fine dust, etc., are filtered through the filter, and the heater is used. Heating of 14 to maintain the temperature of the cleaning liquid at a temperature of 2 5 to 90 ° C; and the two control valves 16 and 20 are respectively located on the pipe 1 2 on both sides of the filter 18 to Automatic timer or manual operation to control the flow or non-circulation of the cleaning fluid. Wherein, the first control valve 16 and the second control valve 20 are provided with a further bypass cleaning device 24, which is composed of a second receiving groove 26 and a second pump 28. A second mixture of hydrofluoric acid, hydrogen peroxide and hydrochloric acid is installed in the second accommodating tank 26, and the second accommodating tank 26 is connected to the cleaning liquid circulation system by the pipeline 1 2 ' The valve 16 is connected to the second pump 28 in the tube. The flow in the road 1 2 ' flows through the filter 18 between the two control valves 16 , 20 . The hydrofluoric acid, the nitrogen peroxide and the hydrochloric acid in the mixed liquid in the second accommodating tank 26 are all semiconductor grades, wherein the hydrofluoric acid is diluted hydrofluoric acid, and the hydrofluoric acid thereof The dilution ratio of acid to water is between 1:10 and 1··100. In addition, the material of the second pump 28 is a pump capable of resisting the mixture of hydrofluoric acid, barium peroxide and hydrochloric acid; and the pipe used in the cleaning liquid circulation system and the cleaning device 24, 2, 1 2 'The material is polyvinylidene fluoride (PVDF), perfluorooxyethylene ether (PFA) or polyetheretherketone (PEEK). When the cleaning liquid in the above cleaning liquid circulation system needs to be replaced, please refer to the second figure, firstly mix the cleaning liquid in the first accommodating tank 10, ammonium hydroxide, hydrogen peroxide and ultrapure water. The liquid is drained, and then ultrapure water is added.

1253961 V. INSTRUCTION DESCRIPTION (5) The first accommodating tank 10 is inside; then the first pump 2 2 is activated and the control valves 16 6 and 20 are opened to form a passage for the pipeline 12 to clean the circulation system. At this time, the heater 14 is temporarily not heated, and only the pipeline is kept flowing, and the second accommodating tank 26 and the second pump 28 of the other bypass cleaning device 24 are in an idle state at this time. When the filter 18 in the cleaning liquid circulation system is to be cleaned, please refer to the third figure, so that the first pump 22, the heater 14 and the first accommodating tank 10 are in an idle state; and the second pump is activated. And opening the first control valve 16 and the second control valve 20 to form another passage by the pipe 1 2 ′, and mixing the hydrofluoric acid, hydrogen peroxide and hydrochloric acid in the second accommodating groove 26 The filter is used to clean the filter 18 to clean the filter. _ wherein hydrofluoric acid reacts with cerium oxide in the cleaning solution to produce cerium tetrafluoride gas; hydrogen peroxide oxidizes cerium and inactive metal particles in the cleaning solution to decompose light organic particles; hydrochloric acid soluble activity Particles of metals and metal compounds. Therefore, after the cleaning liquid passes through the second accommodating tank, the particles are greatly reduced; when the cleaning liquid passes through the filter, the particle number is small, and the probability of the filter being blocked is lowered, so that the life of the filter is naturally prolonged. Moreover, the impurity portion of the cleaning liquid is decomposed, and when the cleaning liquid flows into the first receiving groove again, the cleaning effect can be effectively improved. The invention improves the service life of the filter by using a mixture of hydrofluoric acid, hydrogen peroxide and hydrochloric acid. The chemical mechanism of the mixture is as follows: 4 1. Hydrofluoric acid dissolves cerium oxide: ^

Si02+HF-> H2SiF6+2H20 H2SiF6 (solution)-> SiF4 (gas) + 2HF (liquid) 2. Hydrogen peroxide oxidizes ruthenium and inactive metals in an acidic solution, and decomposes

Page 10 1253961 V. Description of invention (6) Machine particles:

Si-> Si ] r4e

Si "+2H20- Si02+41T, which is an exothermic reaction AG = - 3 4 Ο Κ J / m ο 1 e H 20 2+ 2 HH2e-> 2 Η 20 The combined reaction of the first three reactions is S l + 2 H 20 r> S l 0 2+ 2 Η 20 Cu (solid)-CW solution) + 2e, endothermic reaction Δ G two 65.5 KJ/m〇le The above comprehensive reaction is (: 11 (solid) +} 12 〇 2 +21](Solution)-[:112++2[12〇, total heat of the reaction Δ G=-275 KJ/mole 3, hydrochloric acid dissolved metal compound particles:

Mx0y+2yH^ xM(2y/xH+yH20 M(0H) x+xH" MxH0. 5xH20 In summary, the invention has a design of a cleaning device in the cleaning liquid circulation system, which can effectively remove cerium oxide, strontium and Particles of compounds, metals and their compounds, organic types, etc., and thereby obtain a better cleaning effect to extend the service life of the filter. Therefore, the present invention utilizes a simple structural design to extend the SC-1 cleaning cycle. The effect of the life of the filter in the system and the effect of improving the cleaning effect. The embodiments described above are merely illustrative of the technical idea and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the present invention. The contents are also implemented, and the scope of the invention is not limited thereto, that is, the equivalent changes or modifications made by the spirit of the invention should be covered by the scope of the invention.

Page 11 1253961

Page 12 1253961 Brief Description of the Drawing The first figure is a schematic view showing the structure of the cleaning device of the present invention installed in the cleaning liquid circulation system. The second figure is a schematic view of the structure of the cleaning liquid in the cleaning liquid circulation system of the present invention. The third figure is a schematic view showing the structure of the cleaning filter using the cleaning device of the present invention. Ο

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Claims (1)

1253961 Patent application A washable device for use in a cleaning liquid circulation system, which is installed in a cleaning liquid circulation filter ring system, and the cleaning liquid circulation system includes a cleaning liquid which is connected by a pipeline The first accommodating tank, which is equipped with a filter and a filter to install the filter, the control device is provided with a second and a second salt in the system, such as the Shen system 1) The control of the valve, such as the application of the acid in the valve control, the second pump, please use the nitrogen for the filter, please switch the special valve, please use the tank to filter the miscellaneous valve, set the tank, mix the liquid wash The cleaning process is characterized in that it circulates a range of ammonium oxide cycle quality, and in the cleaning, the ring-based washing liquid causes the flow to be first, and the second process is performed in the second phase of the washing system The oxidizing the cleaning device includes a squirrel containing a accommodating tank, the second control mixed liquid accommodating tank filter, and a hydrogen and a supercritical device, and using the first pump liquid to pass the hydrogen at the two ends of the heater Fluoric acid Using the pipeline valve, the mixing and scrubbing device in the flow or not, the pure water mixer heating and the hydrogen peroxide and the connection device on the pipeline utilize the control; and the liquid in the pipe The cleaning device according to Item 1, wherein the filtering means removes impurities in the cleaning liquid, and includes a stone shovel, a sulphur dioxide, an organic matter, a fine dust, and the like. The control can utilize one of an automatic timer and a manual method to provide the cleaning device of the first aspect, wherein the hydrofluoric acid in the second mixture is diluted hydrofluoric acid. Page 14 1253961 VI. The scope of application for the patent is that the dilution ratio of hydrofluoric acid to water is between 1:10 and 1:100. 0 6 · The cleaning device according to item 1 of the patent application, wherein The hydrofluoric acid, cerium peroxide and hydrochloric acid in the mixed solution are all semiconductor grade. 7. The cleaning device of claim 1, wherein the second pump is a pump that is resistant to the hydrofluoric acid, hydrogen peroxide, and hydrochloric acid. 8. The cleaning device according to claim 1, wherein the material of the pipeline is selected from the group consisting of polyvinylidene fluoride (PVDF), perfluorooxyethylene ether (PFA) and polyetheretherketone (PEEK). One of them. 9. The cleaning device of claim 1, wherein when cleaning the circulation system, the cleaning liquid in the first accommodating tank is discharged first, and the ultra-pure water is installed in the first accommodating In the tank, the ultrapure water is flowed through the pipeline by the first pump to clean the entire circulation system. The cleaning device of claim 1, wherein when cleaning the filter, first closing the first pump and starting the second pump, so that the mixed liquid in the second receiving tank is in the The filter flows by flowing in the line. Page 15