CN115771960A

CN115771960A - Integrated circuit semiconductor ultrapure water device

Info

Publication number: CN115771960A
Application number: CN202211517354.4A
Authority: CN
Inventors: 卢志尧; 邓腊梅
Original assignee: Dongguan Qclean Environmental Protection Equipment Co ltd
Current assignee: Dongguan Qclean Environmental Protection Equipment Co ltd
Priority date: 2022-11-29
Filing date: 2022-11-29
Publication date: 2023-03-10

Abstract

The invention relates to an integrated circuit semiconductor ultrapure water device. The technical scheme comprises the following steps: the system comprises a raw water tank, two raw water pumps connected in parallel, a self-cleaning sand filter, a self-cleaning carbon filter, a first MF filter, a first-stage high-pressure pump, a first-stage reverse osmosis device, a first-stage RO water tank, a second-stage high-pressure pump and a second-stage reverse osmosis device, wherein the output of the second-stage reverse osmosis device is connected with two ways, one way is connected with the raw water tank through an unqualified discharge valve, the other way is connected with the second-stage RO water tank, an EDI pump, a UV (ultraviolet) sterilizer, the second MF filter, the EDI device and a nitrogen-sealed pure water tank in sequence, the output of the nitrogen-sealed pure water tank is subjected to frequency conversion pressurization to a degassing membrane through a frequency conversion water supply pump according to the water use condition, then pure water passes through the two-stage ultraviolet sterilizer and then passes through a two-stage polishing mixed bed, the water quality of the produced water can reach 18.25M omega. This improvement filtration efficiency.

Description

Integrated circuit semiconductor ultrapure water device

Technical Field

The invention relates to the technical field of ultrapure water preparation required by cleaning of semiconductor chips, wafers and silicon carbide wafers, in particular to an integrated circuit semiconductor ultrapure water device.

Background

The existing two-stage reverse osmosis + EDI process is suitable for industries with general requirements on water quality, but the semiconductor industry needs higher water quality, and metal ions, bacteria and various gases remaining in pure water all affect the process yield, the device performance and the device reliability of devices and need to strictly control the content of the metal ions, the bacteria and the gases. Because the water contains corrosive gases such as oxygen, carbon dioxide and the like, the corrosive gases can stay on the surface of a product when a wafer product is cleaned, the wafer product is not cleaned completely, and meanwhile, a pipeline and an equipment system can be corroded, so that the production efficiency and the yield of the wafer product are reduced. Common metal ions mainly include sodium, potassium, iron, copper, nickel, aluminum, etc., and these metal ions have strong mobility to move in the semiconductor, thereby causing the electrical performance of the device to be invalid. The conventional ultrapure water equipment has the following problems: 1. the existing general water use condition is that water supply is started when water is needed, so that dead water can be formed in a pipeline, and once bacteria in a water system are formed on a device due to organic matters generated on the surface of the device due to stagnant circular cleaning, the bacteria can become granular pollutants or introduce unwanted metal ions to the surface of the device, so that the bacteria are easy to breed; 2. the water quality of the traditional ultrapure water equipment can not meet the water consumption requirement of the semiconductor wafer; 3. the traditional equipment has no unqualified water quality discharge function, and when the water quality is unqualified, the EDI device can be damaged irreversibly when the equipment is used as usual. The existing water quality discharge function is arranged, the water quality is unqualified, and the product water quality is ensured to be excellent.

Disclosure of Invention

The invention aims to provide an integrated circuit semiconductor ultrapure water device aiming at the problems of easy bacterial breeding and unqualified water quality in the background technology.

The technical scheme of the invention is as follows: an integrated circuit semiconductor ultrapure water device comprises a raw water tank, wherein the output of the raw water tank is connected with two raw water pumps which are connected in parallel, the raw water conveyed by the raw water pumps sequentially passes through a self-cleaning sand filter and a self-cleaning carbon filter and then is conveyed to a self-cleaning softener to form a complete set of pre-treatment system, the pre-treatment system is filtered by a first MF filter and then conveyed to a primary reverse osmosis unit, the primary reverse osmosis unit sequentially comprises a primary high-pressure pump, a primary reverse osmosis device and a primary RO water tank which are connected with each other, the primary reverse osmosis device is pressurized and conveyed to the primary reverse osmosis device by the primary high-pressure pump, primary reverse osmosis produced water after the primary reverse osmosis device is stored in a primary RO water tank for supplying water to a secondary reverse osmosis device, and the output of the primary RO water tank pressurizes the primary RO water to the secondary reverse osmosis device by the secondary high-pressure pump to further filter organic salts in the water; a first online water quality detector is arranged in the secondary reverse osmosis produced water behind the secondary reverse osmosis device, the output of the secondary reverse osmosis device is connected with two paths, one path is connected with the raw water tank through an unqualified discharge valve, the other path is connected with the secondary RO water tank for supplying water to an EDI system, and meanwhile, the secondary concentrated water is recycled to the raw water tank to relieve the shortage of raw water; and the output of the second-stage RO water tank is pressurized to the second-stage RO water through an EDI pump after being sterilized by a UV sterilizer, and then enters an EDI device after being further filtered by a second MF filter to remove impurities in the water, and the water is stored into a nitrogen-sealed pure water tank after being electrodeionized, the output of the nitrogen-sealed pure water tank is pressurized to a degassing membrane through a variable-frequency water supply pump in a variable-frequency mode according to the water consumption condition, then the pure water passes through a double-stage UV sterilizer and then passes through a double-stage polishing mixed bed, the water quality of the produced water can reach 18.25M omega.

Preferably, the nitrogen-sealed pure water tank is provided with an ultrasonic liquid level meter.

Preferably, the first MF filter is used for microfiltration of water to remove impurities larger than 5 μm.

Preferably, a pressure gauge is arranged on a pipeline between the raw water pump and the self-cleaning sand filter.

Preferably, a flow meter or/and a pressure gauge or/and a pressure control switch are/is arranged on a pipeline connected between the devices.

Preferably, the self-cleaning softener is an NA automatic sodium ion exchange device.

Preferably, two raw water pumps are used and one is standby.

Compared with the prior art, the invention has the following beneficial technical effects: 1. the whole structure water making process does not need manual intervention, and full-automatic water making and full-water halt are realized; 2. a self-cleaning function, wherein when the pre-treatment is started, the pre-treatment must be washed to protect the subsequent process; 3. the function of discharging unqualified water quality of the second level is provided, so that the water quality of RO produced water is ensured to be excellent; 4. the secondary concentrated water is recycled to the raw water tank, so that the raw water pressure can be relieved, water sources can be saved, and meanwhile, the quality of the raw water can be reduced, so that the quality of reverse osmosis produced water is better; 5. supplying nitrogen to the nitrogen-sealed pure water tank to keep the water quality fresh; 6. and (4) conveying the pure water to a water consumption point, then refluxing to a nitrogen-sealed pure water tank, circularly sterilizing, degassing and preserving, maintaining the quality of the pure water, and ensuring the sterile environment in the pipeline. 7. The water supply system has the functions of frequency conversion and constant pressure, automatically adjusts the pressure and keeps the stability of the pressure, and the success rate of finished products can be further improved.

Drawings

FIG. 1 is a schematic view showing the entire connection of an integrated circuit semiconductor ultrapure water apparatus in example 1;

FIG. 2 is a schematic view of the connection of the upper half of FIG. 1;

FIG. 3 is a schematic view of the connection of the left portion of FIG. 2;

FIG. 4 is a schematic view of the connection of the right portion of FIG. 2;

FIG. 5 is a schematic view of the connection of the lower part of FIG. 1;

FIG. 6 is a schematic view of the connection of the left portion of FIG. 5;

fig. 7 is a schematic connection diagram of the right part of fig. 5.

Reference numerals are as follows: a raw water tank 1, a raw water pump 2, a self-cleaning sand filter 3, a self-cleaning carbon filter 4, a self-cleaning softener 5, a first MF filter 6, a first high-pressure pump 7, a first reverse osmosis device 8, a first RO water tank 9, a second high-pressure pump 10, a second reverse osmosis device 11, a first online water quality detector 12, an unqualified discharge valve 13, a second RO water tank 14, an EDI pump 15, a UV (ultraviolet) sterilizer 16, a second MF filter 17, an EDI device 18, a nitrogen-sealed pure water tank 19, a variable-frequency water supply pump 20, a degassing membrane 21, a double-stage ultraviolet sterilizer

22. A double-stage polishing mixed bed 23, a return pipe 24, an ultrasonic liquid level meter 25, a pressure gauge 26, a flow meter 27, a pressure gauge 28 and a pressure control switch 29.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships illustrated in the drawings, and are used merely for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be construed as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or to implicitly indicate the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the present invention, unless otherwise explicitly stated or limited, the terms "mounted," "connected," "fixed," and the like are to be construed broadly, e.g., as being permanently connected, detachably connected, or integral; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or may be connected through the use of two elements or the interaction of two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

Example one

As shown in fig. 1-7, the integrated circuit semiconductor ultrapure water device provided by the present invention comprises a raw water tank 1, wherein two raw water pumps 2 connected in parallel are connected to an output of the raw water tank 1, the raw water pump 2 conveys raw water to pass through a self-cleaning sand filter 3 and a self-cleaning carbon filter 4 in sequence, and then conveys the raw water to a self-cleaning softener 5 for treatment to form a complete pre-treatment system, the pre-treatment system is filtered by a first MF filter 6 and then conveys the raw water to a primary reverse osmosis unit, the primary reverse osmosis unit comprises a primary high-pressure pump 7, a primary reverse osmosis device 8 and a primary RO water tank 9 which are connected with each other in sequence, the primary reverse osmosis unit is pressurized and conveyed to the primary reverse osmosis device 8 by the primary high-pressure pump 7, primary reverse osmosis produced water after the primary reverse osmosis device 8 is stored in the primary RO water tank 9 for the secondary reverse osmosis device 11, an output of the primary RO water tank 9 pressurizes the primary RO water to the secondary reverse osmosis device 11 by the secondary high-pressure pump 10, and further filters organic salts in the water; a first online water quality detector 12 is arranged in the secondary reverse osmosis produced water behind the secondary reverse osmosis device 11, the output of the secondary reverse osmosis device 11 is connected with two paths, one path is connected with the raw water tank 1 through an unqualified discharge valve 13, the other path is connected with a secondary RO water tank 14 for the water of an EDI system, and meanwhile, the secondary concentrated water is recycled to the raw water tank 1 to relieve the shortage of raw water; and the output of the second-stage RO water tank 14 is pressurized to the second-stage RO water through an EDI pump 15, sterilized by a UV sterilizer 16, further filtered by a second MF filter 17 to remove impurities in the water, then enters an EDI device 18, stored in a nitrogen-sealed pure water tank 19 after being electrically deionized, pressurized to a degassing membrane 21 through a variable frequency water supply pump 20 according to the water consumption condition in a variable frequency manner, and then passes through a double-stage ultraviolet sterilizer 22 and a double-stage polishing mixed bed 23 to ensure that the water quality of the produced water can reach 18.25 MOmega.cm, so that water is used for water points, and the residual pure water generated at the water supply points is circulated and refluxed to the nitrogen-sealed pure water tank 19 through a reflux pipe 24.

Preferably, the nitrogen-sealed pure water tank 19 is provided with an ultrasonic liquid level meter 25.

Preferably, the first MF filter 6 is used for microfiltration of water to remove impurities larger than 5 μm.

Preferably, a pressure gauge 26 is provided in a pipe between the raw water pump 2 and the self-cleaning sand filter 3.

Preferably, a flow meter 27 and/or a pressure gauge 28 and/or a pressure control switch 29 are/is arranged on the pipelines connected between the devices.

Preferably, the self-cleaning softener 5 is an NA automatic sodium ion exchange device.

Preferably, two raw water pumps 2 are implemented for one use and one spare.

The specific working principle of the invention is as follows: raw water is discharged from a raw water tank 1, and is conveyed to a self-cleaning sand filter 3 and a self-cleaning carbon filter 4 through a raw water pump 2 (which is used and prepared and can be switched on a touch screen) to filter impurity particles in the raw water and remove organic matters, organic chlorine and the like in the water. Then a self-cleaning softener 5 is used for removing water scale, water alkali and softening water quality so as to reduce the hardness of water and effectively prolong the service life of the ultrafiltration membrane and the reverse osmosis membrane; through preceding pretreatment systems, impurity particulate matter etc. are got rid of basically in the raw water, and some small granule suspended solids, active carbon fine powder then are not got rid of, through first MF filter 6, carry out once more microfiltration, get rid of the impurity more than 5 mu m, carry one-level reverse osmosis unit 8 through the pressurization of one-level high-pressure pump 7, one-level reverse osmosis unit 8 is the heart part that this project was desalted in advance, can effectively hold back the granule and the impurity more than 0.0001 micron, dispel the harmful substance in aquatic: impurities such as bacteria, viruses, heavy metal ions, etc.; the first-stage reverse osmosis produced water is stored in a first-stage RO water tank 9 for a second-stage reverse osmosis device 11 to use, and a second-stage high-pressure pump 10 pressurizes the first-stage RO water to the second-stage reverse osmosis device 11 for further filtering substances such as organic salts and the like in the water; and (3) secondary reverse osmosis water production, wherein when the on-line water quality is detected to be unqualified, a discharge valve with unqualified water quality is opened, and the water cannot flow through the pure water tank to pollute the water quality of a finished product. Reverse osmosis water of suitable quality is delivered to the secondary RO tank 14 for use in the EDI system. The secondary concentrated water is recycled to the raw water tank 1, so that the shortage of raw water is relieved; the EDI pump pressurizes the second-level RO water until the RO water is sterilized by the UV sterilizer 16, then the RO water is filtered by the second MF filter 17 to further remove impurities in the water, and the RO water enters the EDI device 18 and is stored in the nitrogen-sealed pure water tank 19 after being deionized electrically; the pure water in the nitrogen-sealed pure water tank 19 is supplied with nitrogen gas to keep the water fresh. The ultrasonic liquid level meter is adopted to control the water production and standby of the EDI system, the water quality change caused by the contact of other types of liquid level meters and water is avoided, the variable frequency pressure is increased to a degassing membrane by a variable frequency water supply pump according to the water consumption condition, the gases such as oxygen, carbon dioxide and the like in the water are discharged, the pure water passes through a double-stage polishing mixed bed 23 after passing through a double-stage ultraviolet sterilizer 22, the water quality of the produced water can reach 18.25M omega, cm, the produced water is used for water supply points, and the residual pure water flows back to a nitrogen-sealed pure water tank 19 in a circulating mode.

In the embodiment, a controller for controlling the work of each electrical equipment adopts PLC (programmable logic controller) to control the operation of the whole system according to the liquid level of a water tank, a pressure control switch, an electromagnetic valve and the like, and the PLC adopts a remote Internet of things function and has local control and remote control functions to monitor the operation condition of the equipment in real time; meanwhile, the interior of the device is also provided with a multiple protection design, so that the device has the advantages of water shortage protection, water full shutdown, cleaning alarm, RO low pressure, unqualified water quality alarm discharge and the like, and the normal operation of the device is ensured; the self-cleaning function, the pretreatment system stops the machine for automatic flushing, the service life of the reverse osmosis membrane can be prolonged, and during working, the secondary concentrated water is recycled to the raw water tank, so that the raw water pressure is relieved, and the water source is saved. And the second-stage concentrated water can reduce the conductivity of the raw water quality, so that the water quality of the first-stage reverse osmosis system and the second-stage reverse osmosis system is better, the liquid level of the water tank is monitored by the nitrogen-sealed water tank by adopting the ultrasonic level meter, and the water quality change caused by the contact of other types of level meters with water is avoided. The nitrogen is provided to keep the pure water in the water tank fresh, in addition, a two-stage degassing membrane is additionally arranged to remove oxygen, carbon dioxide and other gases in water, so that the pure water is purer, semiconductor chips and other industries with high requirements on water quality can avoid reduction of production efficiency and yield due to corrosive gas in water use, a water supply part adopts a circulation backflow design, the pure water is conveyed to a water using point and then is circulated back to the nitrogen sealed water tank, the pure water flows, and is sterilized, degassed, purified and fresh-kept, the quality and the sterile environment of the pure water are ensured, and a frequency conversion pump is adopted, so that the frequency conversion function is realized. The water supply pressure can be set and the desired pressure can be stably maintained. The principle is that a frequency converter is adopted to control the output of a variable-frequency water supply pump in a variable-frequency mode, a pressure transmitter is adopted to feed back the water supply pressure of a system at the tail end of the process, the water supply pressure is set through a program, the frequency of the variable-frequency water supply pump is automatically adjusted, and the stability of the water supply pressure is guaranteed. When the water supply pressure is reduced, the frequency of the frequency converter is increased, the water quantity and the pressure are increased, and the pressure is kept at the set pressure value. When the water consumption reduces, the pressure increase in the pipeline, frequency conversion working shaft frequency descends to invariable to the settlement pressure, equipment is provided with the unqualified automatic function of removing of quality of water, when detecting that second grade reverse osmosis produces water quality unqualified, will open unqualified quality of water solenoid valve, removes unqualified water, ensures the pure water quality, the damage that protection EDI caused because of the unqualified condition of quality of water. If the water quality is not qualified within 5 minutes of discharge, the equipment enters a standby state and gives an alarm to prompt inspection. The control system adopts the automatic control of a Programmable Logic Controller (PLC) system, and simultaneously monitors the running state of the system through various online instruments. The water making host and the whole system are automatically controlled according to the liquid level of the water tank. The equipment running process, the microcomputer display system running state and the process running condition are clear at a glance. The accumulated working time can be counted, online display and control of water quality, flow, pressure and the like can be realized, the remote Internet of things function is added, unqualified water quality monitoring alarm can be realized, running time statistics, flow accumulation, a water quality data report and water quality condition traceability can be checked. The system has the functions of local control and remote control, monitors the running condition of the equipment in real time and operates.

In conclusion, the water making process of the whole structure does not need manual intervention, and full-automatic water making and full-water stopping are realized; 2. a self-cleaning function, wherein when the pre-treatment is started, the pre-treatment must be washed to protect the subsequent process; 3. the function of discharging unqualified water quality of the second level is provided, so that the water quality of RO produced water is ensured to be excellent; 4. the secondary concentrated water is recycled to the raw water tank, so that the raw water pressure can be relieved, water sources can be saved, and meanwhile, the quality of the raw water can be reduced, so that the quality of reverse osmosis produced water is better; 5. supplying nitrogen to the nitrogen-sealed pure water tank 19 to keep the water fresh; 6. the pure water is delivered to a water consumption point and then flows back to the nitrogen-sealed pure water tank 19, and the circulating sterilization, degassing and fresh-keeping are carried out, so that the quality of the pure water is kept, and the sterile environment in the pipeline is ensured. 7. The water supply system has the functions of frequency conversion and constant pressure, automatically adjusts the pressure and keeps the stability of the pressure, and the success rate of finished products can be further improved.

The above embodiments are only some preferred embodiments of the present invention, and many alternative modifications and combinations of the above embodiments may be made by those skilled in the art based on the technical solution of the present invention and the related teachings of the above embodiments.

Claims

1. An integrated circuit semiconductor ultrapure water device characterized by: the system comprises a raw water tank (1), wherein the output of the raw water tank (1) is connected with two raw water pumps (2) which are connected in parallel, the raw water conveyed by the raw water pumps (2) sequentially passes through a self-cleaning sand filter (3) and a self-cleaning carbon filter (4) and then is conveyed to a self-cleaning softener (5) to be treated to form a set of complete front pretreatment system, the front pretreatment system is filtered by a first MF filter (6) and then conveyed to a first-stage reverse osmosis unit, the first-stage reverse osmosis unit sequentially comprises a first-stage high-pressure pump (7), a first-stage reverse osmosis device (8) and a first-stage RO water tank (9) which are connected with each other, the front pretreatment system is pressurized and conveyed to the first-stage reverse osmosis device (8) by the first-stage high-pressure pump (7), first-stage reverse osmosis produced water after the first-stage reverse osmosis device (8) is stored in the first-stage RO water tank (9) for supplying water to a second-stage reverse osmosis device (11), the output of the first-stage RO water tank (9) pressurizes the first-stage RO water to the second-stage reverse osmosis device (11) by the second-stage high-pressure pump (10), and further filters organic salts in the water; a first online water quality detector (12) is arranged in the secondary reverse osmosis produced water behind the secondary reverse osmosis device (11), the output of the secondary reverse osmosis device (11) is connected with two paths, one path is connected with the raw water tank (1) through an unqualified discharge valve (13), the other path is connected with the secondary RO water tank (14) for supplying water for an EDI system, and meanwhile, the secondary concentrated water is recycled to the raw water tank (1) to relieve the shortage of raw water; and the output of the second-stage RO water tank (14) is pressurized to the second-stage RO water through an EDI pump (15) and sterilized by a UV sterilizer (16), impurities in the water are further filtered by a second MF filter (17), the water enters an EDI device (18), deionized water is stored in a nitrogen-sealed pure water tank (19) after being electroded, the output of the nitrogen-sealed pure water tank (19) is pressurized to a degassing membrane (21) through a variable frequency water supply pump (20) according to the water use condition in a variable frequency mode, and then the pure water passes through a double-stage UV sterilizer (22) and passes through a double-stage polishing mixed bed (23), so that the quality of produced water can reach 18.25M omega cm, water is used for a water supply point, and residual pure water generated by the water supply point circularly flows back to the nitrogen-sealed pure water tank (19) through a return pipe (24).

2. An integrated circuit semiconductor ultrapure water device according to claim 1, wherein: an ultrasonic liquid level meter (25) is arranged on the nitrogen-sealed pure water tank (19).

3. An integrated circuit semiconductor ultrapure water device according to claim 1, characterized in that: the first MF filter (6) is used for performing precise filtration on water to remove impurities larger than 5 mu m.

4. An integrated circuit semiconductor ultrapure water device according to claim 1, characterized in that: a pressure gauge (26) is arranged on a pipeline between the raw water pump (2) and the self-cleaning sand filter (3).

5. An integrated circuit semiconductor ultrapure water device according to claim 1, wherein: and a flow meter (27) or/and a pressure gauge (28) or/and a pressure control switch (29) are/is arranged on a pipeline connected among all the devices.

6. An integrated circuit semiconductor ultrapure water device according to claim 1, wherein: the self-cleaning softener (5) is an NA automatic sodium ion exchange device.

7. An integrated circuit semiconductor ultrapure water device according to claim 1, characterized in that: two raw water pumps (2) are used and standby.