TWI656903B - Filtering device and method of filtering fluid used in semiconductor manufacturing - Google Patents

Abstract

The present disclosure provides a filtering device including a housing, a filter element, and an electric field generating unit. The housing has an inlet and an outlet, wherein the inlet allows a fluid to flow into the housing and the outlet allows fluid to flow out of the housing. A filter element is disposed between the inlet and the outlet for filtering impurities in the fluid flowing through the filter element by an adsorption method. The electric field generating unit is configured to generate an electric field such that the aforementioned impurities move in the direction of the electric field to the filter element.

Description

Filter device and method for filtering fluid used in semiconductor manufacturing

Embodiments of the present invention relate to a semiconductor technology, and more particularly to a filtering apparatus and a filtering method for filtering various fluids used in semiconductor manufacturing.

Semiconductor devices are used in a variety of electronic applications, such as personal computers, mobile phones, digital cameras, and other electronic devices. The fabrication of semiconductor devices typically involves multiple processing procedures, such as fabrication processes including photolithography, etching, ion implantation, doping, annealing, and packaging (hereinafter referred to as processes). In these processes, various types of fluids or chemicals may be used, including, for example, water, photoresist, developer, etchant, slurry, process or cleaning gas, and the like. These fluids are typically filtered before being delivered to a semiconductor fabrication facility for use.

Although existing filtration systems and filtration methods are sufficient to meet their needs, they are still not fully met. Therefore, it is desirable to provide a solution that can improve the effectiveness of impurities in the filtered fluid.

Some embodiments provide a filtering device including a shell a body, a filter element, and an electric field generating unit. The housing has an inlet and an outlet, wherein the inlet allows a fluid to flow into the housing and the outlet allows fluid to flow out of the housing. A filter element is disposed between the inlet and the outlet for filtering impurities in the fluid flowing through the filter element by an adsorption method. The electric field generating unit is configured to generate an electric field such that the aforementioned impurities move in the direction of the electric field to the filter element.

The present disclosure provides a filter device including a housing, a filter element, an electric field generating unit, and an electrode mounting mechanism. The housing is configured to allow a fluid to flow in and out. The filter element is disposed on the flow path of the fluid in the casing to filter impurities in the fluid by an adsorption method. The electric field generating unit is configured to generate an electric field such that the impurity moves along the direction of the electric field to the filter element, wherein the electric field generating unit includes a first electrode, a second electrode, and the first electrode and the second electrode A power source that generates an electric field between them. The electrode mounting mechanism is configured to mount the first electrode and the second electrode to the housing.

The present disclosure provides a method of filtering a fluid used in semiconductor fabrication, including flowing a fluid through a filter element. The filtering method further includes generating an electric field such that impurities in the fluid move in the direction of the electric field to the filter element. Further, the filtering method includes adsorbing the aforementioned impurities by the filter element to filter the fluid.

10‧‧‧Filter system

11‧‧‧ Storage tank

12‧‧‧Semiconductor manufacturing machine

13‧‧‧Pipe system

14‧‧‧Filter device

15‧‧‧Filter device

140‧‧‧shell

141‧‧‧

141A‧‧‧ side wall

141B‧‧‧ bottom wall

142‧‧‧ cover

142A‧‧‧ entrance

142B‧‧‧Export

142C‧‧‧Exhaust port

143‧‧‧Filter elements

143A‧‧‧Opening

143B‧‧‧ surface

143C‧‧‧ surface

150‧‧‧shell

151‧‧‧

152‧‧‧ cover

152A‧‧‧ entrance

152B‧‧‧Export

153‧‧‧Filter elements

153A‧‧‧Opening

153B‧‧‧ surface

153C‧‧‧ surface

154‧‧‧Electrical field generating unit

1541‧‧‧First electrode

1542‧‧‧second electrode

1543‧‧‧Power supply

155‧‧‧ bracket

156‧‧ ‧ partition

200‧‧‧Filter method

201-203‧‧‧ operation

C‧‧‧ fluid

E‧‧‧ electric field

P1‧‧‧ Part/Part 1 / Outer part

P2‧‧‧ Part/Part 2/Inside part

P1’, P2’‧‧ ‧ compartment

X1, X2, X3‧‧‧ impurities

‧‧‧‧ angle

Figure 1 shows a schematic diagram of a filtration system in accordance with some embodiments.

Figure 2A shows a schematic cross-sectional view of the filtration device (14) of Figure 1 in accordance with some embodiments.

Figure 2B shows a partial perspective view of the filter element of Figure 2A.

Figure 2C shows a schematic view of the filter element being non-parallel to the lid of the filter device and the bottom wall of the tank, in accordance with some embodiments.

Figures 3A, 3B show schematic cross-sectional views of the filtration device (14) of Figure 1 in accordance with some embodiments.

Figure 4 shows a schematic cross-sectional view of the filtration device (15) of Figure 1 in accordance with some embodiments.

Figure 5 shows a schematic representation of a portion of the impurities in the fluid that can be adsorbed by the filter element.

Figure 6 shows a schematic diagram of a filter device further comprising an electric field generating unit, in accordance with some embodiments.

Figure 7 shows a schematic representation of the oscillating behavior of impurities in the fluid under the action of an alternating electric field.

Figure 8 shows a schematic view of the electrodes of the electric field generating unit being arranged non-parallel to the filter element, in accordance with some embodiments.

Figure 9 shows a schematic view of the electrodes of the electric field generating unit disposed in the housing, in accordance with some embodiments.

Figure 10 shows a schematic diagram of other configurations of electrodes of an electric field generating unit, in accordance with some embodiments.

Figure 11 shows a flow chart of a method of filtering a fluid used in semiconductor fabrication in accordance with one of some embodiments.

The following disclosure provides many different embodiments or preferred examples to implement various features of the present disclosure. Of course, this disclosure can also be implemented in many different forms. The embodiments are not limited to the embodiments described below. The disclosure of the various components and their arrangement in detail is set forth in the accompanying drawings, and the description of the disclosure will be more fully understood.

Spatially related terms used in the following, such as "below," "below," "lower," "above," "higher," and the like, are used to facilitate the description. The relationship between one element or feature and another element or feature(s). In addition to the orientation depicted in the drawings, these spatially related terms are also intended to encompass different orientations of the device in use or operation. The device may be turned to a different orientation (rotated 90 degrees or other orientation), and the spatially related terms used herein may also be interpreted the same.

It is to be understood that elements not specifically shown or described may be in various forms well known to those skilled in the art. In addition, if a first feature is formed on or above a second feature in the embodiment, it may indicate that the first feature may be in direct contact with the second feature, and may also include additional features. Formed between the first feature and the second feature described above such that the first feature and the second feature are not in direct contact with each other.

The same component numbers and/or characters may be repeated in the following various embodiments, which are for the purpose of simplicity and clarity, and are not intended to limit the specific relationship between the various embodiments and/or structures discussed. In the drawings, the shape or thickness of the structure may be enlarged to simplify or facilitate the marking.

Figure 1 shows a schematic diagram of a filtration system 10 in accordance with some embodiments of the present invention. The filtration system 10 can be used to filter various fluids C (or chemicals) used in a multi-process of semiconductor fabrication, including, for example, water, photoresist, Developer solution, etching solution, polishing solution, process or cleaning gas, etc.

As shown in Fig. 1, the filtration system 10 includes a storage tank 11 for providing storage and protection functions before the fluid C is delivered to a semiconductor manufacturing machine 12 for manufacturing use. In some embodiments, the semiconductor manufacturing machine 12 can be a chemical vapor deposition machine, a physical vapor deposition machine, an etching machine, a thermal oxidation machine, an ion implanter, and a chemical machine. A polishing machine, a rapid temperature annealing machine, a photolithography machine, a diffusion machine, or a semiconductor manufacturing machine that performs other types of processes.

Depending on the different characteristics of the stored fluid C, the storage tank 11 may be selected from a variety of suitable materials to prevent, for example, the material of the storage tank 11 from reacting with the fluid C to cause deterioration or contamination of the fluid C. For example, when the fluid C is a negative tone developer (NTD), the storage tank 11 may be made of a material that does not contain polyethylene (PE) or high density polyethylene, such as polytetrafluoroethylene. A fluorine-based polymer such as polytetrafluoroethylene (PTFE) or perfluoroalkoxy (PFA), thereby preventing the negative developer from being contaminated by polyethylene. However, when the fluid C is water or deionized water, the storage tank 11 may also be made of a plastic material such as polyethylene to reduce the material cost.

Furthermore, the fluid C stored in the storage tank 11 can be transported to the semiconductor manufacturing machine 12 via a series of piping systems 13 before the semiconductor manufacturing machine 12 begins to execute the process. In some embodiments, the piping system 13 includes a plurality of piping, pumps, valves, and flow meters for delivering fluid C to the semiconductor manufacturing machine 12 at a predetermined flow rate for a given period of time. The operation of the piping system 13 can be controlled by a control system (not shown), and the control system can be a single The computer control system is either coupled to the process control system of the semiconductor manufacturing machine 12.

In some embodiments, as shown in FIG. 1, a plurality of filtration devices 14 and 15 are provided in the piping system 13 for filtering impurities in the fluid C (for example, fluid C may be incorporated during preparation or transportation). Particles, metal ions or other foreign matter) to prevent these impurities from affecting or damaging the process results of subsequent semiconductor fabrication machines 12 (eg, such impurities may scratch the surface of wafers processed in semiconductor fabrication machine 12) ).

Please refer to FIG. 2A, which shows a cross-sectional view of the filtering device 14 of FIG. 1 in accordance with some embodiments. The filter device 14 includes a housing 140 that includes a tank 141 for receiving fluid C (FIG. 1) to be filtered and a lid 142 for closing the tank 141. The trough body 141 can be designed in any shape suitable for receiving the fluid C and loading a filter element 143 which will be described later. In some embodiments, the trough body 141 includes a cylindrical side wall 141A and a bottom wall 141B coupled to the side wall 141A, wherein a space for containing the fluid C is formed between the side wall 141A and the bottom wall 141B. In other embodiments, the trough 141 may have other suitable shapes, such as hollow squares, hexagons, octagons, or other polygons.

The tank body 141 may be made of a material that does not react with the fluid C to be filtered and is capable of withstanding fluid pressure. In some embodiments, the material of the tank 141 includes stainless steel, nickel, aluminum, alloys of the foregoing metals, or other suitable metals or alloys. In other embodiments, in order to prevent the metal material or ions from contaminating the fluid C to be filtered to affect the subsequent semiconductor process, a protective layer such as a telfon material may be further formed inside the cavity 141. Alternatively, the material of the tank body 141 may be selected from other suitable plastic materials (such as polyethylene) or The insulating material (for example, polytetrafluoroethylene) is determined by the characteristics of the fluid C to be filtered. As for the cover 142, the same or similar material as the groove 141 can be generally selected.

In some embodiments, the cover 142 can be attached to the trough 141 by, for example, an O-ring, a gasket, or other optional seal (not shown), thereby preventing fluid C in the trough 141 from occurring. Leakage, while allowing the cover 142 to be removed from the trough 141 to allow for processing of the interior of the trough 141 (e.g., loading the filter element 143 into the trough 141). Alternatively, the lid body 142 may be integrally formed with the tank body 141 by means of a joint such as welding or adhesion, thereby achieving hermetic sealing and effectively preventing leakage of the fluid C.

In some embodiments, as shown in FIG. 2A, the cover 142 may be formed with an inlet 142A and an outlet 142B for allowing a fluid C to be filtered to flow into the housing 140 and allow a passage (filter element 143). The filtered fluid C flows out of the housing 140 (shown by the directional arrows in the figure). Alternatively, the inlet 142A and the outlet 142B may be formed on the side wall 141A and/or the bottom wall 141B of the tank body 141, respectively. Additionally, to facilitate removal (replacement of the filtration device 14 in the piping system 13), the inlet 142A and the outlet 142B may be provided with various optional valve or pipe joints (not shown).

Next, referring to FIGS. 2A and 2B, the filter 140 of the filter device 1 is provided with a filter element 143, for example, a film having a porous structure (Fig. 2B). Filter element 143 may be disposed between inlet 142A and outlet 142B and divide the interior of housing 140 into two portions P1 and P2 that are substantially symmetrical. In some embodiments, the filter element 143 can be perpendicular to the bottom wall of the lid 142 and the trough 141 (Fig. 2A). The inlet 142A is connected to the first portion P1, and the outlet 142B is connected to the second portion P2, whereby the flow from the inlet 142A into the housing 140 Body C needs to flow through filter element 143 (shown by the directional arrow in the figure) before exiting housing 140 from the outlet so that it can be filtered by filter element 143. In other embodiments, the filter element 143 may also be non-perpendicular to the bottom wall of the cover 142 and the trough 141 (as shown in FIG. 2C).

In addition, the filter element 143 may have other different structural configurations as long as it is disposed on the flow path of the fluid C in the housing 140. For example, FIG. 3A shows that in some embodiments, the filter element 143 (porous film) may also be configured to connect the cover 142 and divide the interior of the housing 140 into an inner portion P2 and an outer portion P1 surrounding the inner portion P2. (The filter element 143 is generally rectangular when viewed in cross section), with the outer portion P1 connecting the inlet 142A and the inner portion P2 connecting the outlet 142B. As such, fluid C entering the housing 140 from the inlet 142A may also be required to flow through the filter element 143 (as indicated by the directional arrows in the figure) before exiting the housing 140 from the outlet so as to be filtered by the filter element 143. In other embodiments, the position of the inlet 142A and the outlet 142B may also be interchanged such that the inner portion P2 is coupled to the inlet 142A and the outer portion P1 is coupled to the outlet 142B. In other embodiments, the filter element 143 can also be generally trapezoidal when viewed in cross-section (as shown in Figure 3B).

In the embodiment of Figures 3A, 3B, the cover 142 of the filter device 14 is also formed with an exhaust port 142C that can be used to controllably (e.g., controlled by the aforementioned control system) to exit the maintenance filter device 14 Gases that may be generated during or other emergency situations to controllably release pressure that may accumulate in the filtering device 14. In addition, in order to facilitate the installation or operation of the exhaust port 142C, the exhaust port 142C may also be provided with various optional valve or pipe joints (not shown).

As shown in Fig. 2B, the filter element (film) 143 has a plurality of openings 143A (through the opposing surfaces 143B, 143C of the filter element 143) for allowing fluid C to flow through the filter element 143 (as indicated by the directional arrows in the figure) Show). At the same time, the opening 143A can serve as a filtering mechanism for preventing impurities in the fluid C having a size larger than the opening 143A from passing through the filter element 143. It will be appreciated that the size of the aperture 143A depends, at least in part, on the type of process performed by the semiconductor fabrication machine 12 and the type of fluid C to be filtered by the filtration device 14 (and filter element 143). For example, the size of the opening 143A generally depends on the size of the impurities in the fluid C that is desired to be removed by filtration, while other factors, such as a pressure drop that may pass through the filtering device 14, may also be considered. In some embodiments, the cross-sectional shape of the opening 143A may be a circle, a triangle, a square, an octagon, or other polygons.

The filter element 143 can be made of a material that is chemically inert to the fluid C to be filtered, thereby preventing fluid C from reacting with the filter element 143 during filtration to produce a change in properties. In some embodiments, the material of the filter element 143 may comprise a non-polar polymer, such as ultra-high molecular weight polyethylene (UPE), polytetrafluoroethylene, or the like. Non-polar polymer. Thereby, the ability of the filter element 143 to filter impurities of a particular size can be physically (or structurally) controlled by the size of the opening 143A.

Referring now to Figures 1 and 4 together, Figure 4 shows a cross-sectional view of the filtering device 15 of Figure 1 in accordance with some embodiments. After fluid C is filtered through filter unit 14, it can be sent to filter unit 15 to further filter out smaller impurities from fluid C. It should be understood that the filtering device 15 includes a shell The body 150 includes a tank 151 for receiving the fluid C (Fig. 1) to be filtered and a lid 152 for closing the tank 151. The cover 152 may be formed with an inlet 152A and an outlet 152B for allowing a fluid C to be filtered to flow into the housing 150 and allowing a fluid C filtered by a filter element 153 (which will be described later) to flow out of the housing 150. (as indicated by the directional arrow in Figure 4). The inlet 152A of the lid 152 can be connected to the outlet 142B of the filter unit 14 by a conduit. The foregoing design of the casing 150, the tank body 151, the lid body 152, the inlet 152A, and the outlet 152B of the filtering device 15, and the casing 140, the tank body 141, the lid body 142, the inlet 142A, and the outlet 142B of the filtering device 14 (including structural configuration and materials, etc.) are similar, so the details are not repeated here. However, in other embodiments, the filter device 15 may also be of a different design than the filter device 14 (eg, the two filter devices employ the designs of Figures 2A and 3, respectively).

As shown in Fig. 4, a filter element 153 is mounted in the housing 150 of the filter unit 15, for example, a film having a porous structure. Similar to filter element 143 in filter device 14 described above, filter element 153 also has a plurality of openings 153 (shown in phantom, through opposing surfaces 153B, 153C of filter element 153) that can be used to allow fluid C to flow through filter element 153, The impurities in the fluid C having a size larger than the opening 153A are prevented from passing through the filter element 153 (that is, impurities of different sizes can be filtered by the size adjustment of the opening 153A). A difference between the filter element 153 and the filter element 143 (Figs. 2A, 2B) is that the size of the opening 153A of the filter element 153 is smaller than the size of the opening 143A of the filter element 143, thereby enabling a smaller fluid C. The impurities (these impurities may affect the process results of the subsequent semiconductor manufacturing machine 12) are removed by filtration.

In other embodiments, it is also possible to only set in the filtration system 10. The filter device 15 is placed and the filter device 14 is omitted.

In the above embodiment, although the film is used as an example to illustrate the structural features of the filter elements 143, 153, other structures having an opening (for example, a metal or ceramic sintered mesh structure or a porous columnar structure) may also be used as the filter. Elements 143, 153.

Further, in order to improve the filtering ability, the material of the filter element 153 may also be changed to a polar polymer which does not contaminate the fluid C to be filtered, such as a nylon or other similar structure of a polar polymer. It is used to adsorb polar impurities or non-polar impurities in the fluid C (not wishing to run to the end of the semiconductor manufacturing machine 12). It will be understood that the term "adsorption" as used herein encompasses both "physical adsorption" and "chemosorption" as is well known to those of ordinary skill in the art (both adsorption mechanisms may act simultaneously or simultaneously), wherein "Chemical adsorption" (also referred to as "active adsorption") means that the interaction between a molecule and a molecule is a chemical bond such as an ionic bond, a covalent bond or a metal bond, and "physical adsorption" refers to adsorption. The force between molecules and molecules is a generalized physical bond such as Van der waals force or electrostatic attraction.

Referring to FIG. 5, it is shown a schematic diagram in which a portion of the impurity X1 in the fluid C can be adsorbed by the filter element 153. As shown in Fig. 5, the polar or non-polar impurities in the fluid C are to be adsorbed by the filter element 153 for filtration, provided that these impurities X1 must contact the filter element 153 or be very close to the filter element 153 (with opportunity and filtration) A chemical or physical bond is formed between the elements 153, so that the impurity X2 in the fluid C that moves with the fluid C (as indicated by the directional arrow in the figure) and does not come into contact with or spaced apart from the filter element 153 cannot be The filter element 153 is effectively adsorbed and removed. Therefore, in order to increase the movement of impurities in the fluid C to The ratios and opportunities on the filter element 153, in turn, improve the ability of the filtration device 15 to utilize the adsorption mode to filter impurities, and some embodiments of the present invention further provide the following technical means.

Referring to FIG. 6, in some embodiments, (in addition to the components described in FIG. 4), the filtering device 15 further includes an electric field generating unit 154 including a first electrode 1541 and a second electrode 1542. And a power supply 1543. The first electrode 1541 and the second electrode 1542 are, for example, two planar electrode plates made of a conductive material (for example, metal), respectively disposed on opposite sides of the filter element 153. For example, the first electrode 1541 may be disposed on the filter element 153 near the inlet 152A. One side, and the second electrode 1542 may be disposed on the other side of the filter element 153 near the outlet 152B. The power source 1543 is for applying a corresponding (direct current or alternating current) voltage to the first electrode 1541 and the second electrode 1542, and generates a (direct current or alternating current) electric field E therebetween. In the embodiment of Fig. 6, in order to prevent the electric field E from being affected by the metal shielding effect, the housing 150 may be made of a suitable material other than metal.

In some embodiments, the outer side of the housing 150 of the filter device 15 also has a plurality of extended brackets 155 (electrode mounting mechanisms) for mounting and positioning the first and second electrodes 1541 and 1542 to the housing 150, respectively. In the embodiment of FIG. 6, the bracket 155 can set the first electrode 1541 and the second electrode 1542 to be substantially parallel to the filter element 153. The bracket 155 can include any mechanism suitable for clamping, clamping, locking or adhering the first electrode 1541 and the second electrode 1542 (eg, the bracket 155 in the embodiment of FIG. 6 includes a clamping edge that can be clamped to achieve a fixed Clamping mechanism). Additionally, the bracket 155 can use the same or a different material than the housing.

With the above configuration, the impurity to be filtered (under the action of the electric field E) in the fluid C (Fig. 1) passing through the filtering device 15 can be moved in the direction of the electric field E (indicated by the direction arrow in the figure) to Filter element 153. In more detail, when the power source 1543 provides a DC voltage (as shown in FIG. 6), a DC current E can be generated between the first electrode 1541 and the second electrode 1542, and the fluid C is filtered. The impurity X3 (under the action of the electric field E) can be uniformly moved to the surface 153B of the filter element 153 (near the inlet 152A) in the direction of the electric field E to be adsorbed thereto. In some embodiments, the direction of the electric field of the direct current electric field E is substantially perpendicular to the filter element 153. When the power source 1543 provides an alternating voltage, an alternating electric field can be generated between the first electrode 1541 and the second electrode 1542, and the direction of the electric field changes with time (for example, exhibiting a sinusoidal waveform), and the fluid C is desired. The filtered impurity X3 (under the action of the electric field E) can oscillate in the direction of the electric field E (as shown in Fig. 7) and lengthen the time during which the impurity X3 passes through the filter element 153, thereby increasing the contact of the impurity X3 with the filter element 153. And the opportunity to be absorbed by it.

In contrast, in the absence of an electric field, the impurities in fluid C can only be moved to filter element 153 by a random diffusion mode (with a relatively limited diffusion limit). Therefore, the filtering device 15 in the present embodiment can drive the impurity X3 to be filtered in the fluid C to move in a directional manner by the electric field E force, and increase the movement of the impurities X3 onto the filter element 153 or with the filtering. The element 153 is in contact with the opportunity, and the filtering device 15 can be filtered by means of adsorption.

It should be understood that the purpose of using the electric field is to overcome the energy barrier that needs to be crossed when the impurity X3 to be filtered is diffused and adsorbed to the filter element 153, so as to enhance the adsorption efficiency, and the similar relationship words include diffusion limit reaction (diffusion). Limit reaction) or diffusion limit adsorption. This effect is more remarkable when the concentration of the impurity X3 to be filtered is extremely low, so that impurities which are not desired to be present at the end of the semiconductor manufacturing machine 12 can be effectively prevented from causing defects in subsequent processes. In a typical semiconductor process, the ideal defect ratio needs to be controlled below about 1 to 100 counts/12 inch wafer.

In some embodiments, the magnitude and/or frequency of the voltage provided by the power source 1543 can be controlled and adjusted based on different characteristics of the impurity (whether polar or non-polar) of the fluid C to be filtered, thereby enabling corresponding and sufficient The electric field E forces to drive these impurities. For example, when the impurity to be filtered is a polar impurity, the power source 1543 can be controlled (for example, by artificial or computer control) to provide a lower voltage DC or AC voltage, and the generated electric field E and the polar impurities are The electrostatic attraction between them drives impurities. On the other hand, when the impurity to be filtered is a non-polar impurity, the power source 1543 can be controlled to supply a higher voltage DC or AC voltage, and driven by the generated electric field E and the induced dipole force between these non-polar impurities. Impurities. In some embodiments, the power supply 1543 provides a voltage range from 0.5 V (volts) to 1000 V, while the power supply 1543 provides a voltage frequency between 0 Hz (hertz) and 100 KHz.

In addition, the magnitude of the voltage supplied by the power source 1543 can also be adjusted accordingly depending on the size of the impurity to be filtered. For example, when the impurities to be filtered have a larger size, the power source 1543 can provide a higher voltage to generate sufficient electric field E force to drive the impurities. Conversely, when the impurities to be filtered have a smaller size, the power source 1543 can provide only a lower voltage to reduce energy consumption.

In addition, the impurities to be filtered are driven by the electric field E force. The difficulty of the power supply 1543 can also provide a voltage in a continuous or discontinuous manner to produce a continuous electric field or a discontinuous electric field. For example, when the impurities to be filtered are non-polar impurities and/or have a larger size, the power source 1543 can continuously provide a higher voltage DC or AC voltage during the passage of the fluid C through the filter device 15 to produce a continuous And sufficient electric field E force to drive these impurities to move smoothly onto the filter element 153. Conversely, when the impurity to be filtered is a polar impurity and/or has a smaller size, the power source 1543 can provide a lower pressure discontinuously (i.e., intermittently) while the fluid C passes through the filtering device 15. The DC or AC voltage can also generate an electric field E force sufficient to drive these impurities.

It should also be understood that the disclosed embodiments use an electric field to enhance the filtration efficiency of the filter element 153. The difference from the conventional capillary electrophoresis separation technique includes that the capillary electrophoresis separation technique does not utilize the filter element 153 (filter membrane). Rather, the direct use of electric field forces causes charged particles of different sizes in the fluid to produce different rates of movement to achieve separation effects, thus requiring the application of a relatively large electric field (eg, applying a voltage of at least 20 KV). In contrast, the use of the electric field in the embodiment of the present invention is mainly to increase the chance of diffusion of the impurity X3 to be filtered to the filter element 153, and thus can be relatively lower than the high voltage used in capillary electrophoresis. Additionally, capillary electrophoresis is only suitable for micro-separation (e.g., [mu]L), while the filtration device 15 of the presently disclosed embodiments can be used to filter larger amounts of fluid (e.g., greater than 1 L) in semiconductor fabrication.

There are many other variations and modifications of the disclosed embodiments. For example, Figure 8 shows that the bracket 155 on the outside of the housing 150 can be adjusted and the first electrode 1541 and the second electrode of the electric field generating unit 154, according to some embodiments. 1542 is disposed not parallel to the filter element 153 such that the direction of the (eg, direct current) electric field E generated by the electric field generating unit 154 can form an angle between 0 and 180 degrees with the surface 153B of the filter element 153 (but not An angle α including 0 degrees, 90 degrees, and 180 degrees, for example, an angle α of 45 degrees. As such, the direction relative to the electric field E is substantially perpendicular to the filter element 153 (ie, the first electrode 1541 is substantially parallel to the second electrode 1542 and the filter element 153), except for the impurity X3 to be filtered in the fluid C. It is still possible to move along the direction of the electric field E to the filter element 153, and it is also possible to reduce the chance that these impurities X3 can easily pass through the opening 153A of the filter element 153 (inclination of the incident can increase the impurity X3 to the side wall of the opening 153A. The opportunity to improve the ability of the filtration device 15 to utilize the adsorption mode to filter impurities.

FIG. 9 shows that the first electrode 1541 and the second electrode 1542 of the electric field generating unit 154 may also be disposed in the housing 150 according to some embodiments. As shown in FIG. 9, the first electrode 1541 and the second electrode 1542 may be respectively disposed in the compartments P1' and P2' of the housing 150 which are further separated by the partition 156. When the cover 152 is connected to the slot 151, At this time, the compartments P1' and P2' are not in communication with other spaces in the housing 150, thereby preventing the first electrode 1541 from contacting the second electrode 1542 and the fluid C to be filtered, possibly contaminating the fluid C or causing the fluid C. Deterioration. The power source 1543 of the electric field generating unit 154 may pass through a wire opening (not shown) on the cover 152 to provide a voltage to the first electrode 1541 and the second electrode 1542.

In the embodiment of Fig. 9, the spacer 156 may be made of a suitable material other than metal to prevent the electric field E from being affected by the metal shielding effect. In some embodiments, if the fluid C to be filtered has no doubt that it may be contaminated by metal materials or ions, the first electrode 1541 and the second electrode 1542 may be directly They are disposed in the casing 150 (provided in the first portion P1 and the second portion P2, respectively), and the partition 156 is omitted. In addition, although not explicitly shown in FIG. 9, the compartments P1' and P2' may be designed to have a sufficiently large space and/or have a positioning structure to allow the first electrode 1541 and the second electrode 1542 to be configured to be non-parallel to the filtration. Element 153 or forms an appropriate angle with filter element 153.

Figure 10 shows that the filter device 15 can have a similar structural design as the filter device 14 of Figure 3, in accordance with some embodiments. In addition, one of the electrodes of the electric field generating unit 154 (for example, the first electrode 1541, which is a strip or a rod electrode) may be disposed in the inner portion P2 of the housing 150 (that is, the filter element 153 is surrounded by the first electrode 1541). Outside). Although not shown, the first electrode 1541 may be disposed in a compartment formed inside the cover 152 or coupled to the inside of the cover 152 by other optional mechanisms. The other electrode of the electric field generating unit 154 (for example, the second electrode 1542, which is an annular electrode) may be disposed opposite to an annular compartment P1' (separated by the partition 156) adjacent to the side wall of the casing 150. . The power source 1543 of the electric field generating unit 154 may pass through a wire opening (not shown) on the cover 152 to provide a voltage to the first electrode 1541 and the second electrode 1542. In other alternative embodiments, the second electrode 1542 can also be positioned outside of the housing 150 by a bracket 155 (Figs. 6 and 8) extending from the outside of the housing 150.

Some embodiments of the present invention also provide a filtering method 200, as shown in the flow chart of FIG. For the sake of explanation, the flowchart will be described together with reference to FIGS. 1 and 4 to 10. First, the filtration method 200 includes an operation 201 of flowing a fluid through a filter element. In some embodiments, a fluid C (eg, including water, photoresist, developer, etchant, slurry, process or cleaning gas, etc.) is delivered to a semiconductor fabrication machine 12 via a piping system 13 For semiconductors Before being used for manufacture, at least one filter device 15 (in which a filter element 153 such as a porous film is installed) is first flowed to filter impurities (such as particles, which may affect or damage the process results of the semiconductor manufacturing machine 12). Metal ions or other foreign matter).

Next, the filtering method 200 further includes an operation 202 of generating an electric field such that impurities in the fluid to be filtered move in the direction of the electric field to the filter element. In some embodiments, an electric field generating unit 154 is provided and an electric field E is generated by the electric field generating unit 154 through one of the filter elements 153. The electric field E may be a direct current electric field, and its electric field direction may be non-parallel to the surface 153B of the filter element 153. For example, the direction of the electric field E and the surface 153B may form an angle, for example, between 0 and 180 degrees (but not Contains an angle α of 0 degrees and 180 degrees). Alternatively, the electric field E may also be an alternating electric field whose electric field direction changes with time. In addition, the electric field E may be a continuous electric field or a discontinuous electric field, depending on the characteristics of the impurity X3 to be filtered in the fluid C (for example, whether or not it has polarity or size). These impurities X3 can be moved to the filter element 153 in the direction of the electric field E under the action of the electric field E.

In addition, the filtration method 200 further includes an operation 203 of adsorbing the aforementioned impurities by the filter element to filter the fluid. In some embodiments, the material of the filter element 153 can be modified to use a polar polymer that does not contaminate the fluid C to be filtered, such as a polar polymer of nylon or other similar structure, to adsorb (including) chemistry. The adsorption "and" physical adsorption" is guided by the electric field E to the (polar or non-polar) impurity X3 on the filter element 153. In addition, the filter element 153 also has a plurality of openings 153A for allowing fluid C to flow through the filter element 153 and for filtering impurities in the fluid C that are larger in size than the openings 153A.

In summary, the disclosed embodiments have the following advantages: by applying an electric field, the impurities to be filtered in the fluid can be actively driven to move along the direction of the electric field to the filter element, so as to prevent the impurities from being in contact with the filter element. Just as the fluid passes through the opening in the filter element. In this way, the ability of the filtration device to filter impurities by the adsorption method can be improved. In addition, the strength, frequency and manner of application of the electric field can be adjusted according to the different characteristics of the impurities to be filtered, so that corresponding and sufficient electric field forces can be generated to drive the impurities.

According to some embodiments, a filter device is provided that includes a housing, a filter element, and an electric field generating unit. The housing has an inlet and an outlet, wherein the inlet allows a fluid to flow into the housing and the outlet allows fluid to flow out of the housing. A filter element is disposed between the inlet and the outlet for filtering impurities in the fluid flowing through the filter element by an adsorption method. The electric field generating unit is configured to generate an electric field such that the aforementioned impurities move in the direction of the electric field to the filter element.

According to some embodiments, the electric field generating unit includes a first electrode, a second electrode, and a power source for generating an electric field between the first electrode and the second electrode. The first electrode is disposed on one side of the filter element adjacent to the inlet, and the second electrode is disposed on the other side of the filter element adjacent to the outlet.

According to some embodiments, the first electrode and the second electrode are disposed outside of the housing.

According to some embodiments, at least one of the first electrode and the second electrode is disposed in the housing.

According to some embodiments, the filter element further has a plurality of openings for allowing fluid to flow through the filter element and filtering impurities in the fluid that are larger in size than the openings.

According to some embodiments, a filter device is provided that includes a housing, a filter element, an electric field generating unit, and an electrode mounting mechanism. The housing is configured to allow a fluid to flow in and out. The filter element is disposed on the flow path of the fluid in the casing to filter impurities in the fluid by an adsorption method. The electric field generating unit is configured to generate an electric field such that the impurity moves along the direction of the electric field to the filter element, wherein the electric field generating unit includes a first electrode, a second electrode, and the first electrode and the second electrode A power source that generates an electric field between them. The electrode mounting mechanism is configured to mount the first electrode and the second electrode to the housing.

In accordance with some embodiments, a method of filtering a fluid for use in semiconductor fabrication is provided, including flowing a fluid through a filter element. The filtering method further includes generating an electric field such that impurities in the fluid move in the direction of the electric field to the filter element. Further, the filtering method includes adsorbing the aforementioned impurities by the filter element to filter the fluid.

According to some embodiments, the aforementioned electric field is a direct current electric field.

According to some embodiments, the direction of the direct current electric field is not parallel to the surface of the filter element.

According to some embodiments, the aforementioned electric field is an alternating electric field.

The embodiments and their advantages are described in detail above, and it is understood that various changes, substitutions and modifications may be made in the present disclosure without departing from the spirit and scope of the disclosure. Further, the scope of the present application is not intended to be limited to the specific embodiments of the process, the machine, the manufacture, the material composition, the tool, the method and the steps described in the specification. As will be readily understood by one of ordinary skill in the art, in accordance with the present disclosure, Processes, machines, fabrications, compositions, tools, methods or steps that are either conventional or will be developed in the future that perform substantially the same functions or achieve substantially the same results as the corresponding embodiments described herein. Therefore, the scope of the appended claims is intended to cover such processes, machines, manufacture, compositions of matter, tools, methods or steps. In addition, each patent application scope constitutes a separate embodiment, and combinations of different application patent scopes and embodiments are within the scope of the disclosure.

Claims (10)

A filter device comprising: a housing having an inlet and an outlet, the inlet allowing a fluid to flow into the housing, and the outlet allowing the fluid to flow out of the housing; a filter element disposed at the inlet and the outlet An impurity for filtering the fluid flowing through the filter element by an adsorption method; and an electric field generating unit configured to generate an electric field such that the impurities move in the direction of the electric field to the filter element Above, wherein the fluid does not pass through the electric field generating unit. The filter device of claim 1, wherein the electric field generating unit comprises a first electrode, a second electrode, and a power source for generating the electric field between the first electrode and the second electrode. The first electrode is disposed on a side of the filter element adjacent to the inlet, and the second electrode is disposed on a side of the filter element adjacent to the outlet. The filter device of claim 2, wherein the first electrode and the second electrode are disposed outside the housing. The filter device of claim 2, wherein at least one of the first electrode and the second electrode is disposed in the housing. The filter device of claim 1, wherein the filter element further has a plurality of openings for allowing the fluid to flow through the filter element and filtering impurities in the fluid that are larger in size than the openings. A filter device comprising: a housing configured to allow a fluid to flow in and out; a filter element disposed in the flow path of the fluid in the housing for Filtering impurities in the fluid by an adsorption method; an electric field generating unit configured to generate an electric field such that the impurities move along the direction of the electric field to the filter element, wherein the electric field generating unit includes a first An electrode, a second electrode, and a power source for generating the electric field between the first electrode and the second electrode; and an electrode mounting mechanism configured to mount the first electrode and the second electrode to The housing and the first electrode and the second electrode are not in contact with the fluid. A method of filtering a fluid used in semiconductor fabrication, comprising: flowing the fluid through a filter element; generating an electric field such that impurities in the fluid move in the direction of the electric field to the filter element, wherein the fluid The unit is not generated by an electric field generating the electric field; and the impurities are adsorbed by the filter element to filter the fluid. A method of filtering a fluid used in semiconductor fabrication as described in claim 7 wherein the electric field is a constant current electric field. A method of filtering a fluid used in semiconductor manufacturing as described in claim 8 wherein the direction of the direct current electric field is not parallel to the surface of the filter element. A method of filtering a fluid used in semiconductor manufacturing as described in claim 7 wherein the electric field is an alternating electric field.