A cleaning device and a cleaning method

Abstract

This invention relates to the field of semiconductor cleaning equipment technology, and discloses a cleaning apparatus and a cleaning method. The cleaning apparatus includes: a cleaning chamber; a fixing device for supporting and fixing the object to be cleaned; a first nozzle, the first nozzle having multiple liquid pipes and multiple gas pipes inside, the liquid pipes including at least a first liquid pipe for spraying a first cleaning liquid onto the object to be cleaned and a second liquid pipe for spraying a second cleaning liquid onto the object to be cleaned; the gas pipes including at least a first gas pipe and a second gas pipe, both of which are used to spray inert gas onto the object to be cleaned, the spraying direction of the first gas pipe is the same as the spraying direction of the first liquid pipe and the second liquid pipe, and the spraying direction of the second gas pipe forms a preset angle with the spraying direction of the first gas pipe. The cleaning apparatus and cleaning method provided by this invention can effectively avoid watermark defects and improve cleaning quality.

Description

Technical Field

[0001] This invention relates to the field of semiconductor cleaning equipment technology, and in particular to a cleaning apparatus and cleaning method. Background Technology

[0002] With the rapid development of semiconductor integrated circuit manufacturing technology, the feature size of integrated circuit chips has entered the deep submicron stage. Consequently, the feature size of critical contaminants (such as particles) that cause failure or damage to ultra-fine circuits on the chip has also been greatly reduced. In the integrated circuit manufacturing process, semiconductor wafers typically undergo multiple process steps such as thin film deposition, etching, and polishing. These process steps become important sites for contaminant generation. To maintain the cleanliness of the wafer surface and eliminate contaminants deposited during each process step, the wafer surface must be cleaned after each step. Therefore, cleaning has become the most common process step in integrated circuit manufacturing, aiming to effectively control the contamination level at each step to achieve the objectives of each process step.

[0003] The quality of existing wafer cleaning devices needs to be improved. Summary of the Invention

[0004] The purpose of this invention is to provide a cleaning device and a cleaning method that can effectively avoid watermark defects and improve cleaning quality.

[0005] To address the aforementioned technical problems, embodiments of the present invention provide a cleaning device, comprising: a cleaning chamber; a fixing device disposed within the cleaning chamber for supporting and fixing an object to be cleaned; a first nozzle disposed within the cleaning chamber, the first nozzle having multiple liquid conduits and multiple gas conduits inside, the liquid conduits including at least a first liquid conduit for spraying a first cleaning liquid onto the object to be cleaned and a second liquid conduit for spraying a second cleaning liquid onto the object to be cleaned; the gas conduits including at least a first gas conduit and a second gas conduit, both the first gas conduit and the second gas conduit being used to spray inert gas onto the object to be cleaned, the spraying direction of the first gas conduit being the same as the spraying directions of the first liquid conduit and the second liquid conduit being at a preset angle to the spraying direction of the second gas conduit, the preset angle being greater than 0 degrees and less than or equal to 90 degrees.

[0006] In addition, the liquid pipeline also includes a third liquid pipeline for spraying drying liquid onto the object to be cleaned, the spraying direction of the third liquid pipeline being the same as that of the first liquid pipeline. By spraying drying liquid onto the surface of the object to be cleaned, the effect of quickly drying the object is achieved.

[0007] In addition, the cleaning device also includes a jetting aid structure with multiple through holes, which is disposed below the first nozzle. The inert gas ejected from the first gas pipeline is sprayed toward the object to be cleaned through the multiple through holes.

[0008] In addition, the plurality of through holes include a first hole and a second hole, wherein the inert gas ejected from the first gas pipeline is sprayed onto the object to be cleaned through the first hole; the first liquid pipeline, the second liquid pipeline and the third liquid pipeline pass through the second hole.

[0009] Additionally, the second gas line includes an annular opening surrounding the first nozzle, through which the inert gas is ejected.

[0010] Additionally, the second gas conduit includes an injection hole with at least four openings surrounding the first nozzle, through which the inert gas is ejected.

[0011] In addition, the cleaning chamber includes an air inlet device and an air outlet device. The air inlet device is used to spray air into the cleaning chamber, and the air outlet device is used to exhaust the airflow from the cleaning chamber. By providing the air inlet and air outlet devices, the cleaning chamber can be cleaned before the object to be cleaned enters the cleaning chamber, thereby maintaining the cleanliness of the cleaning chamber.

[0012] In addition, the air intake device includes an air intake duct and an air jet structure connected to the air intake duct, the air jet structure being used to spray gas from the air intake duct toward the cleaning chamber.

[0013] Additionally, it includes a first control valve and a second control valve for controlling gas flow. The air inlet pipe includes a first air inlet pipe and a second air inlet pipe. The first control valve is disposed between the first air inlet pipe and the jet structure. The second control valve is disposed between the second air inlet pipe and the jet structure.

[0014] In addition, the jet structure includes multiple through holes communicating with the cleaning chamber. This structure ensures that the gas ejected by the jet structure can cover all areas of the cleaning chamber, thereby improving the cleaning effect of the cleaning device.

[0015] Additionally, it includes a first robotic arm connected to the first nozzle, used to move the first nozzle above the fixing device. This structural arrangement makes the cleaning device more automated, thereby reducing process time.

[0016] Additionally, it includes a second nozzle disposed within the cleaning chamber. The second nozzle has a fourth liquid conduit and a fifth liquid conduit inside. The fourth liquid conduit is used to spray a third cleaning liquid onto the object to be cleaned, and the fifth liquid conduit is used to spray a fourth cleaning liquid onto the object to be cleaned.

[0017] Additionally, a second robotic arm is included, which is connected to the second nozzle and is used to move the second nozzle above the fixing device.

[0018] Accordingly, embodiments of the present invention also provide a cleaning method, comprising: providing an object to be cleaned; providing a cleaning chamber; controlling the object to be cleaned to enter the cleaning chamber, and spraying a first cleaning liquid and an inert gas onto the object to be cleaned, wherein the spraying direction of the inert gas includes a first direction that is the same as the spraying direction of the first cleaning liquid and a second direction that forms a preset angle with the spraying direction of the first cleaning liquid, the preset angle being greater than 0 degrees and less than or equal to 90 degrees; spraying a second cleaning liquid and the inert gas onto the object to be cleaned, wherein the spraying direction of the second cleaning liquid is the same as the spraying direction of the first cleaning liquid.

[0019] Compared with the prior art, the technical solution provided by the embodiments of the present invention has the following advantages:

[0020] By setting up a fixing device, the object to be cleaned can be fixed to the fixing device during cleaning in the cleaning chamber. A first nozzle is provided, with multiple liquid lines inside. These liquid lines include at least a first liquid line for spraying a first cleaning liquid onto the object and a second liquid line for spraying a second cleaning liquid. Since the cleaning process requires multiple types of cleaning liquids, this structure allows for the spraying of different cleaning liquids through a single nozzle, eliminating the need to change nozzles during cleaning and simplifying the cleaning process. The first nozzle also contains a first gas line and a second gas line for spraying inert gas onto the object. The spray directions of the first gas line, the first liquid line, and the second liquid line are the same. During the cleaning process, when the cleaning liquid does not completely cover the object, the surface of the object exposed to the cleaning liquid... Surfaces readily react with oxygen to form precipitates. When the water on the surface of the object to be cleaned evaporates, these precipitates form watermarks, affecting the cleaning quality. By setting up a first gas pipeline, whose spray direction is the same as that of the first and second liquid pipelines, the inert gas sprayed by the first gas pipeline reduces the oxygen content above the object to be cleaned when the cleaning liquid is sprayed by the first or second liquid pipeline, thus avoiding watermark defects and improving cleaning quality. In addition, the spray direction of the second gas pipeline forms a preset angle with the spray direction of the first gas pipeline, which is greater than 0 degrees and less than or equal to 90 degrees. That is to say, the second gas pipeline sprays a lateral inert gas flow onto the surface of the object to be cleaned, thereby preventing suspended particles in the cleaning chamber from falling onto the surface of the object to be cleaned, and quickly removing fluoride ions and water molecules evaporated by the cleaning liquid, further improving cleaning quality. Attached Figure Description

[0021] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0022] Figure 1 This is a schematic diagram of the cleaning apparatus provided according to the first embodiment of the present invention;

[0023] Figure 2 This is another structural schematic diagram of the cleaning apparatus provided according to the first embodiment of the present invention;

[0024] Figure 3 This is a flowchart of a cleaning method provided according to a second embodiment of the present invention;

[0025] Figure 4This is another flowchart of the cleaning method provided according to the second embodiment of the present invention.

[0026] Figure 5 This is a flowchart of a silicon wafer cleaning method provided according to a third embodiment of the present invention.

[0027] Figure 6 This is a flowchart of a non-pure silicon wafer cleaning method provided according to the fourth embodiment of the present invention. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the various embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been presented in the various embodiments of the present invention to enable the reader to better understand the present invention. However, the technical solutions claimed in the present invention can be implemented even without these technical details and various changes and modifications based on the following embodiments.

[0029] The first embodiment of the present invention relates to a cleaning device 100, the specific structure of which is as follows: Figure 1 As shown, it includes:

[0030] The cleaning chamber 1; a fixing device 2, which is disposed in the cleaning chamber 1 and is used to support and fix the object to be cleaned; a first nozzle 3, which is disposed in the cleaning chamber and has multiple liquid pipes 31 and multiple gas pipes 32 inside. The liquid pipes 31 include at least a first liquid pipe 311 for spraying a first cleaning liquid onto the object to be cleaned and a second liquid pipe 312 for spraying a second cleaning liquid onto the object to be cleaned; the gas pipes 32 include at least a first gas pipe 322 and a second gas pipe 321. Both the first gas pipe 322 and the second gas pipe 321 are used to spray inert gas onto the object to be cleaned. The spraying directions of the first gas pipe 322, the first liquid pipe 311 and the second liquid pipe 312 are the same. The spraying direction of the second gas pipe 321 is at a preset angle to the spraying direction of the first gas pipe 322. The preset angle is greater than 0 degrees and less than or equal to 90 degrees.

[0031] By setting the fixing device 2, the object to be cleaned can be fixed on the fixing device 2 during cleaning in the cleaning chamber 1, avoiding the object from moving during cleaning and resulting in poor cleaning effect. By setting the first nozzle 3, the first nozzle 3 is provided with multiple liquid pipelines 31. The liquid pipelines 31 include at least a first liquid pipeline 311 for spraying a first cleaning liquid onto the object to be cleaned and a second liquid pipeline 312 for spraying a second cleaning liquid onto the object to be cleaned. Since the cleaning process of the object to be cleaned requires the use of multiple types of cleaning liquids, this structure can achieve the spraying of different cleaning liquids through a single nozzle, so that it is not necessary to change different nozzles when cleaning the object to be cleaned, making the cleaning process of the object to be cleaned simpler. The first nozzle 3 is also provided with a first gas pipeline 322 and a second gas pipeline 321 for spraying inert gas onto the object to be cleaned. The spraying direction of the first gas pipeline 322, the first liquid pipeline 311 and the second liquid pipeline 312 is the same. During the cleaning process, if the cleaning solution does not completely cover the object, the exposed surface of the object is prone to reacting with oxygen and water to form precipitates. When the water on the surface of the object evaporates, these precipitates form watermarks. The first gas pipe 322, whose spray direction is the same as that of the first liquid pipe 311 and the second liquid pipe 312, reduces the oxygen content above the object to be cleaned when the cleaning liquid is sprayed by the first liquid pipe 311 or the second liquid pipe 312, thus avoiding watermark defects and improving cleaning quality. In addition, the second gas pipe 321 forms a preset angle with the first gas pipe 322, which is greater than 0 degrees and less than or equal to 90 degrees. That is, the second gas pipe 321 sprays a lateral inert gas flow onto the surface of the object to be cleaned, thereby preventing suspended particles in the cleaning chamber 1 from falling onto the surface of the object to be cleaned and quickly removing fluoride ions and water molecules evaporated by the cleaning liquid, further improving cleaning quality.

[0032] It should be noted that the object to be cleaned in this embodiment is a wafer, and its surface is silicon. A wafer refers to a silicon wafer used in the fabrication of silicon semiconductor integrated circuits. Various circuit element structures can be fabricated on silicon wafers to become integrated circuit products with specific electrical functions. The cleaning solution can be a fluorinated chemical, such as DHF, HF with a concentration of 49%, or a mixture of HF and HNO3.

[0033] The implementation details of the cleaning device 100 in this embodiment will be described in detail below. The following implementation details are provided for ease of understanding and are not necessary for implementing this solution.

[0034] In this embodiment, the liquid conduit 31 further includes a third liquid conduit 313 for spraying a drying liquid onto the object to be cleaned. The spraying direction of the third liquid conduit 313 is the same as that of the first liquid conduit 311. By spraying the drying liquid onto the surface of the object to be cleaned, the object is dried quickly. Preferably, the drying liquid in this embodiment is isopropanol (IPA). By utilizing the low surface tension and high evaporation rate of IPA, the surface of the object to be cleaned can be dried quickly. It is understood that this embodiment does not specifically limit the material of the drying liquid, and other materials can also be used.

[0035] It is worth mentioning that the cleaning device 100 also includes an auxiliary jet structure 9 with multiple through holes 90. The auxiliary jet structure 90 is disposed below the first nozzle 3, and the inert gas ejected from the first gas pipeline 322 is sprayed onto the object to be cleaned through the multiple through holes 90. In this way, the inert gas airflow ejected from the first gas pipeline 322 can be evenly distributed and the flow rate can be more stable.

[0036] Specifically, the through hole 90 includes a first hole 901 and a second hole 902. The inert gas ejected from the first gas pipe 322 is sprayed onto the object to be cleaned through the first hole 901. The first liquid pipe 311, the second liquid pipe 312 and the third liquid pipe 313 pass through the second hole 902. In other words, the first liquid pipe 311, the second liquid pipe 312, and the third liquid pipe 313 spray liquid directly onto the surface of the object to be cleaned through the second hole 902. The first gas pipe 322 is set on the auxiliary spraying structure 9. After the first gas pipe 322 sprays out inert gas, the inert gas is sprayed onto the object to be cleaned through the first hole 901. It can be understood that there can be one or more first holes 901. By setting multiple first holes 901 on the auxiliary spraying structure 9, the gas flow distribution can be uniform and the flow rate can be more stable, thereby making the cleaning liquid surface formed on the surface of the object to be cleaned more uniform and further improving the cleaning effect of the object to be cleaned. It can be understood that the second gas pipe 321 sprays out from the side of the first nozzle 3. That is to say, the gas sprayed out by the second gas pipe 321 does not pass through the through hole 90. It should be noted that this embodiment does not specifically limit the number of through holes or the shape of the auxiliary spraying structure 9. Different shapes of auxiliary spraying structures 9 and different numbers of through holes 90 can be set on the auxiliary spraying structure 9 according to actual needs.

[0037] Furthermore, the second gas conduit 321 includes an annular opening surrounding the first nozzle 3, through which inert gas is ejected. It is understood that the shape of the second gas conduit 321 is not limited to this; it can also include an injection hole with at least four openings surrounding the first nozzle 3, through which inert gas is ejected. Preferably, the openings are evenly spaced around the first nozzle 3. It should be noted that this embodiment does not specifically limit the number of openings; other numbers of openings are also possible.

[0038] Specifically, the cleaning chamber 1 includes an air inlet device 11 and an air outlet device 12. The air inlet device 11 is used to spray air into the cleaning chamber 1, and the air outlet device 12 is used to exhaust the airflow from the cleaning chamber 1. By providing the air inlet device 11 and the air outlet device 12, the cleaning chamber can be cleaned before the object to be cleaned enters the cleaning chamber 1, thereby maintaining the cleanliness of the cleaning chamber.

[0039] Preferably, the air intake device 11 includes an air intake duct 111 and an air jet structure 112 connected to the air intake duct 111, the air jet structure 112 being used to spray the gas in the air intake duct 111 toward the cleaning chamber 1.

[0040] More preferably, the cleaning device 100 further includes a first control valve 4 and a second control valve 5 for controlling gas flow. The air inlet duct 111 includes a first air inlet duct 1111 and a second air inlet duct 1112. The first control valve 4 is disposed between the first air inlet duct 1111 and the jet structure 112; the second control valve 5 is disposed between the second air inlet duct 1112 and the jet structure 112. Specifically, before the object to be cleaned enters the cleaning chamber 1, the first control valve 4 is open and the second control valve 5 is closed. The first air inlet duct 1111 sprays air into the cleaning chamber 1 via the jet structure 112 to maintain the cleanliness of the cleaning chamber. After the object to be cleaned enters the cleaning chamber 1, the first control valve 4 is closed and the second control valve 5 is open. The second air inlet duct 1112 sprays an inert gas (such as nitrogen) into the cleaning chamber 1 via the jet structure 112 to reduce the oxygen content in the cleaning chamber, preventing oxygen from reacting chemically with the liquid on the surface of the object to be cleaned during the cleaning process and producing precipitation, thereby further improving the cleaning effect.

[0041] Furthermore, the jet structure 112 in this embodiment may include multiple through holes 1120 communicating with the cleaning chamber. These through holes 1120 can be evenly distributed at the top of the cleaning chamber 1, ensuring that the gas ejected from the jet structure 112 covers all areas of the cleaning chamber, guaranteeing uniform gas distribution within the cleaning chamber, and thus improving the cleaning effect of the cleaning device 100. Alternatively, the multiple through holes 1120 can be arranged around the cleaning chamber 1. For example, a square cleaning chamber 1 may have jet structures 112 on each side wall except the bottom wall. This structure also achieves the technical effect of ensuring that the gas ejected from the through holes 1120 covers all areas of the cleaning chamber 1. It should be noted that this embodiment does not specifically limit the number of through holes 1120; different numbers of through holes 1120 can be inserted into the jet structure 112 according to actual needs.

[0042] It is worth mentioning that the system also includes a first robotic arm 6, which is connected to the first nozzle 3 and is used to move the first nozzle 3 above the fixing device 2. This structure makes the cleaning device 100 more automated, thereby reducing process time.

[0043] It should be noted that, as Figure 2 As shown, the cleaning device 100 also includes a second nozzle 7, which is disposed within the cleaning chamber 1. The second nozzle 7 contains a fourth liquid conduit 71 and a fifth liquid conduit 72. The fourth liquid conduit 71 is used to spray a third cleaning liquid onto the object to be cleaned, and the fifth liquid conduit 72 is used to spray a fourth cleaning liquid onto the object to be cleaned. It can be understood that with this structure, the cleaning device 100 can use different cleaning liquids to clean the object according to its material, thereby further improving the cleaning quality. It is worth mentioning that this embodiment does not specifically limit the number of nozzles; it may also include a third nozzle, a fourth nozzle, etc.

[0044] Specifically, it also includes a second robotic arm 8, which is connected to the second nozzle 7 and is used to move the second nozzle 7 above the fixing device 2. This structure makes the cleaning device 100 more automated, thereby reducing process time.

[0045] It is understood that the fixing device 2 in this embodiment includes a fixing part 21 fixed to the cleaning chamber 1 and a chuck 22 rotatably connected to the fixing part 21 for carrying the object to be cleaned. The chuck 22 can rotate with the fixing part 21 as the central axis so that the object to be cleaned fixed on the chuck 22 can rotate so that the cleaning liquid can be evenly distributed on the object to be cleaned.

[0046] For ease of understanding, the following example illustrates how to clean a silicon wafer in this embodiment, using a silicon wafer (surface is silicon) as the object to be cleaned, hydrofluoric acid as the first cleaning solution, water as the second cleaning solution, nitrogen as the inert gas, and isopropanol as the drying solution:

[0047] (1) Before the wafer is transferred to the cleaning chamber 1, the first control valve 4 is opened and the second control valve 5 is closed. The first air inlet pipe 1111 sprays air into the cleaning chamber 1 through the jet structure 112 to maintain the cleanliness of the cleaning chamber. The robotic arms in the cleaning chamber remain in their original positions.

[0048] (2) When the wafer is transferred to the cleaning chamber 1, the first control valve 4 is closed and the second control valve 5 is opened. The second air inlet pipe 1112 sprays nitrogen into the cleaning chamber 1 through the jet structure 112 to reduce the oxygen and water molecule content in the cleaning chamber, so that the silicon on the wafer surface is difficult to react with oxygen and water to generate water mark defects during the cleaning process. The robotic arms in the cleaning chamber remain in their original positions.

[0049] (3) The first robotic arm 6 moves the first nozzle 3 above the fixing device 2 (i.e., the position of the wafer center) and sprays hydrofluoric acid onto the wafer surface through the first liquid pipeline 311 (flow rate of 300 to 2500 ml / min). At the same time, the chuck 22 rotates (speed of 300 to 1500 rpm) to perform wet cleaning to remove particles or oxide layers (such as silicon oxide) on the wafer surface. At the same time, the second gas pipeline 321 sprays a lateral nitrogen gas flow (flow rate of 2 to 30 liters / min) to prevent suspended particles in the air of the cleaning chamber 1 from falling onto the wafer surface and to quickly remove evaporated fluoride ions or water molecules. At the same time, the first gas pipeline 322 sprays a downward nitrogen gas flow (flow rate of 1 to 10 liters / min) to reduce the oxygen content above the wafer and avoid watermark defects caused by uneven liquid coverage. Understandably, if the nitrogen injection speed is too low, the oxygen content above the wafer cannot be effectively reduced, thus failing to effectively suppress the formation of watermark defects; if the nitrogen injection speed is too high, it may cause uneven coverage of the cleaning fluid above the wafer, thereby affecting the cleaning effect. By using nitrogen in this flow rate range, the above phenomena can be avoided, thus ensuring the cleaning effect of the wafer.

[0050] (4) The first liquid line 311 stops spraying hydrofluoric acid onto the wafer surface, and the second liquid line 312 sprays water onto the wafer surface (flow rate of 700 to 2500 ml / min). At the same time, the chuck 22 rotates (speed of 300 to 1500 rpm) to remove the chemicals from the wafer surface. The second gas line 321 sprays a lateral nitrogen gas flow (flow rate of 2 to 30 liters / min), and the first gas line 322 sprays a downward nitrogen gas flow (flow rate of 1 to 10 liters / min) to further avoid the generation of watermark defects.

[0051] (5) The second liquid line 312 stops spraying water onto the wafer surface, and the third liquid line 313 sprays isopropanol onto the wafer surface (flow rate of 500 to 500 ml / min). At the same time, the chuck 22 rotates (speed of 50 to 1000 rpm). By utilizing the low surface tension and high evaporation of isopropanol, the wafer is dried quickly. The second gas line 321 sprays a lateral nitrogen flow (flow rate of 2 to 30 L / min), and the first gas line 322 sprays a downward nitrogen flow (flow rate of 1 to 10 L / min) to accelerate the evaporation of isopropanol and remove the water on the wafer, thus achieving a rapid drying effect.

[0052] (6) The third liquid line 313 stops spraying isopropanol onto the wafer surface. At this time, the chuck 22 rotates at high speed (1500 to 3000 rpm); the second gas line 321 sprays a lateral nitrogen gas flow (flow rate of 30 to 150 liters / minute), and the first gas line 322 sprays a downward nitrogen gas flow (flow rate of 10 to 100 liters / minute), further accelerating the wafer drying and achieving the drying effect.

[0053] (7) Stop supplying nitrogen into the air inlet channel and remove the silicon wafer from the cleaning chamber 1.

[0054] For ease of understanding, the following example illustrates how to clean a non-pure silicon wafer (with a surface of silicon nitride, silicon oxide, titanium nitride, or metallic titanium, tungsten, etc.), using APM as the third cleaning solution, water as the fourth cleaning solution, and isopropanol as the drying solution.

[0055] (1) Before the wafer is transferred to the cleaning chamber 1, the first control valve 4 is opened and the second control valve 5 is closed. The first air inlet pipe 1111 sprays air into the cleaning chamber 1 through the jet structure 112 to maintain the cleanliness of the cleaning chamber. The robotic arms in the cleaning chamber remain in their original positions.

[0056] (2) The wafer is transferred to the cleaning chamber 1 and air is maintained (according to the process characteristics, non-pure silicon wafers will not produce watermark defects, so nitrogen is not required, which can reduce costs). The robotic arms in the cleaning chamber remain in their original positions.

[0057] (3) The second robotic arm 8 moves the second nozzle 7 above the fixing device 2 (i.e., the position of the wafer center) and sprays APM (flow rate of 300 to 2500 ml / min) onto the wafer surface through the fourth liquid line 71. At the same time, the chuck 22 rotates (speed of 300 to 1500 rpm) to perform wet cleaning to remove particles or oxide layers (such as titanium oxide) on the wafer surface and maintain air supply.

[0058] (4) The fourth liquid line 71 stops spraying APM onto the wafer surface, and the fifth liquid line 72 sprays water onto the wafer surface (flow rate of 700 to 2500 ml / min). At the same time, the chuck 22 rotates (speed of 300 to 1500 rpm) and maintains air supply.

[0059] (5) The fifth liquid line 72 stops spraying water onto the wafer surface, the second robotic arm 8 moves the second nozzle 7 away, the first robotic arm 6 moves the first nozzle 3 above the fixing device 2, and the third liquid line 313 sprays isopropanol onto the wafer surface (flow rate of 500 to 500 ml / min). At the same time, the chuck 22 rotates (speed of 50 to 1000 rpm). By utilizing the low surface tension and high evaporation of isopropanol, the wafer is dried quickly. The second gas line 321 sprays a lateral nitrogen flow (flow rate of 2 to 30 liters / min), and the first gas line 322 sprays a downward nitrogen flow (flow rate of 1 to 10 liters / min) to accelerate the evaporation of isopropanol and remove the water on the wafer, thus achieving a rapid drying effect.

[0060] (6) The third liquid line 313 stops spraying isopropanol onto the wafer surface. At this time, the chuck 22 rotates at high speed (1500 to 3000 rpm); the second gas line 321 sprays a lateral nitrogen gas flow (flow rate of 30 to 150 liters / minute), and the first gas line 322 sprays a downward nitrogen gas flow (flow rate of 10 to 100 liters / minute), further accelerating the wafer drying and achieving the drying effect.

[0061] (7) Remove the non-pure silicon wafer from the cleaning chamber 1.

[0062] The second embodiment of the present invention relates to a cleaning method, the specific process of which is as follows: Figure 3 As shown, it includes:

[0063] S201: Provide the items to be cleaned.

[0064] Regarding step S201, specifically, the object to be cleaned in this embodiment is a wafer. It can be understood that the wafer can be a silicon wafer (the wafer surface is silicon) or a non-pure silicon wafer (the wafer surface is silicon nitride, silicon oxide, titanium nitride, or metallic titanium, tungsten, etc.).

[0065] S202: Provides a cleaning chamber.

[0066] Regarding step S202, specifically, the cleaning chamber provided in this embodiment is the same as the cleaning chamber in the above embodiment.

[0067] S203: Control the object to be cleaned to enter the cleaning chamber and spray the first cleaning liquid and inert gas onto the object to be cleaned.

[0068] Regarding step S203, specifically, the injection direction of the inert gas includes a first direction that is the same as the injection direction of the first cleaning liquid, and a second direction that forms a preset angle with the injection direction of the first cleaning liquid, wherein the preset angle is greater than 0 degrees and less than or equal to 90 degrees. Preferably, the preset angle is 90 degrees; preferably, the inert gas is nitrogen.

[0069] It is worth mentioning that the first cleaning solution used in this embodiment can be different for wafers of different materials. For example, when cleaning silicon wafers, the first cleaning solution can be DHF, HF with a concentration of 49%, or a mixture of HF and HNO3. When cleaning non-pure silicon wafers, the first cleaning solution can be SPM (sulfuric acid + hydrogen peroxide + pure water), SOM (sulfuric acid + odor + pure water), APM (ammonium hydroxide + hydrogen peroxide + pure water / diluted ammonium hydroxide), HPM (hydrochloric acid + hydrogen peroxide + pure water), etc. This embodiment does not specifically limit the chemical composition of the first cleaning solution.

[0070] S204: Spray a second cleaning fluid and an inert gas onto the object to be cleaned.

[0071] Regarding step S204, specifically, in this embodiment, the second cleaning solution is water.

[0072] In another feasible embodiment, before controlling the object to be cleaned to enter the cleaning chamber, the method further includes: introducing air into the cleaning chamber; after controlling the object to be cleaned to enter the cleaning chamber and before spraying the first cleaning liquid and inert gas onto the object to be cleaned, the method further includes: introducing nitrogen into the cleaning chamber; after spraying the second cleaning liquid and the inert gas onto the object to be cleaned, the method further includes: spraying a drying liquid and the inert gas onto the object to be cleaned, wherein the spraying direction of the drying liquid is the same as the spraying direction of the first cleaning liquid. This method can further improve the cleaning quality.

[0073] The specific process of this implementation method is as follows: Figure 4 As shown, it includes:

[0074] S301: Provide the item to be cleaned.

[0075] S302: Provides a cleaning chamber.

[0076] S303: Introduce air into the cleaning chamber.

[0077] Regarding step S303, specifically, the cleaning chamber includes an air inlet device and an air outlet device. The air inlet device is used to spray air into the cleaning chamber 1, and the air outlet device is used to exhaust the airflow from the cleaning chamber. By setting up the air inlet and air outlet devices, the cleaning chamber can be cleaned before the object to be cleaned enters the cleaning chamber, thereby maintaining the cleanliness of the cleaning chamber. Specifically, the air inlet device blows up the powdery particles in the cleaning chamber, and the air in the cleaning chamber will carry the blown-up powdery particles. The air outlet device can quickly exhaust the airflow containing powdery particles from the cleaning chamber, thereby preventing the powdery particles from falling back into the cleaning chamber and improving the cleaning effect of the cleaning device.

[0078] S304: Control the entry of the object to be cleaned into the cleaning chamber.

[0079] S305: Introduce nitrogen gas into the cleaning chamber.

[0080] Specifically, step S305 involves spraying nitrogen into the cleaning chamber, which reduces the oxygen content within the chamber and prevents oxygen from reacting chemically with the liquid on the surface of the object during the cleaning process, thus preventing precipitation and further improving the cleaning effect.

[0081] S306: Spray the first cleaning fluid and inert gas onto the object to be cleaned.

[0082] S307: Spray a second cleaning fluid and inert gas onto the object to be cleaned.

[0083] S308: Spray drying liquid and inert gas onto the object to be cleaned.

[0084] Regarding step S308, specifically, the drying liquid in this embodiment is isopropanol (IPA). IPA is a colorless and transparent liquid with an odor similar to a mixture of ethanol and acetone. By utilizing the properties of IPA's low surface tension and high evaporation rate, it is possible to quickly dry the surface of the object to be cleaned. It is understood that this embodiment does not specifically limit the material of the drying liquid, and other materials can also be used.

[0085] Compared to existing technologies, the embodiments of this invention, by providing a fixing device, allow the object to be cleaned to be fixed to the fixing device during cleaning within the cleaning chamber; by providing a first nozzle, the first nozzle having multiple liquid pipelines inside, including at least a first liquid pipeline for spraying a first cleaning liquid onto the object and a second liquid pipeline for spraying a second cleaning liquid onto the object, this structure allows for the spraying of different cleaning liquids through a single nozzle, eliminating the need to change different nozzles during cleaning and simplifying the cleaning process; the first nozzle also has a first gas pipeline and a second gas pipeline for spraying inert gas onto the object, with the first gas pipeline, the first liquid pipeline, and the second liquid pipeline spraying in the same direction, ensuring that during the cleaning process, before the cleaning liquid completely covers the object... During cleaning, the surface of the item exposed to the cleaning solution easily reacts with oxygen and water to form precipitates. When the water on the surface of the item evaporates, these precipitates form watermarks, affecting the cleaning quality. By setting up a first gas pipeline, whose spray direction is the same as that of the first and second liquid pipelines, the inert gas sprayed by the first gas pipeline reduces the oxygen content above the item, thus avoiding watermarks and improving cleaning quality. In addition, the spray direction of the second gas pipeline forms a preset angle with that of the first gas pipeline, which is greater than 0 degrees and less than or equal to 90 degrees. This means that the second gas pipeline sprays a lateral inert gas flow onto the surface of the item, preventing suspended particles in the cleaning chamber from falling onto the surface and further improving cleaning quality.

[0086] The third embodiment of the present invention relates to a method for cleaning silicon wafers. This embodiment uses the cleaning apparatus described in the above embodiments to clean the silicon wafers. The specific process is as follows: Figure 5 As shown, it includes:

[0087] S401: Before the wafer is transferred to the cleaning chamber, the first control valve is opened and the second control valve is closed, and the first air inlet pipe sprays air into the cleaning chamber through the jet structure.

[0088] S402: When the wafer is transferred to the cleaning chamber, the first control valve is closed, the second control valve is opened, and the second air inlet pipe sprays nitrogen into the cleaning chamber through the jet structure.

[0089] S403: The first robotic arm moves the first nozzle above the fixed device, the first liquid line sprays hydrofluoric acid onto the wafer surface, the chuck rotates at the same time, the second gas line sprays a lateral nitrogen flow, and the first gas line sprays a downward nitrogen flow.

[0090] S404: The first liquid line stops spraying hydrofluoric acid onto the wafer surface, the second liquid line sprays water onto the wafer surface, the chuck rotates simultaneously, the second gas line sprays lateral nitrogen flow, and the first gas line sprays downward nitrogen flow.

[0091] S405: The second liquid line stops spraying water onto the wafer surface, the third liquid line sprays isopropanol onto the wafer surface, the chuck rotates simultaneously, the second gas line sprays lateral nitrogen flow, and the first gas line sprays downward nitrogen flow.

[0092] S406: The third liquid line stops spraying isopropanol onto the wafer surface, the chuck rotates at high speed, the second gas line sprays lateral nitrogen flow, and the first gas line sprays downward nitrogen flow.

[0093] S407: Stop supplying nitrogen to the air intake duct and remove the silicon wafer from the cleaning chamber.

[0094] Those skilled in the art will understand that this embodiment can achieve the same technical effects as the above-described embodiments, and will not be repeated here to avoid repetition.

[0095] The fourth embodiment of the present invention relates to a cleaning method for non-pure silicon wafers. This embodiment uses the cleaning apparatus described in the above embodiments to clean the non-pure silicon wafers. The specific process is as follows: Figure 6 As shown, it includes:

[0096] S501: Before the wafer is transferred to the cleaning chamber, the first control valve is opened and the second control valve is closed, and the first air inlet pipe sprays air into the cleaning chamber through the jet structure.

[0097] S502: The wafer is transferred to the cleaning chamber, and air is maintained.

[0098] S503: The second robotic arm moves the second nozzle above the fixture and sprays APM onto the wafer surface through the fourth liquid line.

[0099] S504: The fourth liquid line stops spraying APM onto the wafer surface, the fifth liquid line sprays water onto the wafer surface, the chuck rotates simultaneously, and air is maintained.

[0100] S505: The fifth liquid line stops spraying water onto the wafer surface, the second robotic arm moves the second nozzle away, the first robotic arm moves the first nozzle above the fixing device, the third liquid line sprays isopropyl alcohol onto the wafer surface, and the chuck rotates simultaneously.

[0101] S506: The third liquid line stops spraying isopropanol onto the wafer surface, the chuck rotates at high speed, the second gas line sprays lateral nitrogen flow, and the first gas line sprays downward nitrogen flow.

[0102] S507: Remove the non-pure silicon wafer from the cleaning chamber.

[0103] Those skilled in the art will understand that this embodiment can achieve the same technical effects as the above-described embodiments, and will not be repeated here to avoid repetition.

[0104] Those skilled in the art will understand that the above embodiments are specific examples of implementing the present invention, and in practical applications, various changes in form and detail may be made without departing from the spirit and scope of the present invention.

Claims

1. A cleaning device, characterized in that, include: Clean the chamber; A fixing device is disposed in the cleaning chamber for supporting and fixing the object to be cleaned; A first nozzle is disposed within the cleaning chamber, and the first nozzle contains multiple liquid conduits and multiple gas conduits. The liquid pipeline includes at least a first liquid pipeline for spraying a first cleaning liquid onto the object to be cleaned and a second liquid pipeline for spraying a second cleaning liquid onto the object to be cleaned. The gas pipeline includes at least a first gas pipeline and a second gas pipeline. Both the first gas pipeline and the second gas pipeline are used to spray inert gas onto the object to be cleaned. The spraying directions of the first gas pipeline, the first liquid pipeline, and the second liquid pipeline are the same. The spraying direction of the second gas pipeline is at a preset angle to the spraying direction of the first gas pipeline. The preset angle is greater than 0 degrees and less than or equal to 90 degrees.

2. The cleaning apparatus of claim 1, wherein The liquid pipeline also includes a third liquid pipeline for spraying drying liquid onto the object to be cleaned, the spraying direction of the third liquid pipeline being the same as that of the first liquid pipeline.

3. The cleaning apparatus of claim 2, wherein The cleaning device also includes a jetting aid structure with multiple through holes, which is located below the first nozzle. Inert gas ejected from the first gas pipeline is sprayed onto the object to be cleaned through the multiple through holes.

4. The cleaning apparatus of claim 3, wherein The plurality of through holes includes a first hole and a second hole, wherein the inert gas ejected from the first gas pipeline is sprayed onto the object to be cleaned through the first hole; the first liquid pipeline, the second liquid pipeline and the third liquid pipeline pass through the second hole.

5. The cleaning device according to claim 1, characterized in that, The second gas line includes an annular opening surrounding the first nozzle, through which the inert gas is ejected.

6. The cleaning apparatus according to claim 1, characterized in that, The second gas conduit includes an injection hole with at least four openings surrounding the first nozzle, through which the inert gas is ejected.

7. The cleaning device according to claim 1, characterized in that, The cleaning chamber includes an air inlet device and an air outlet device. The air inlet device is used to spray air into the cleaning chamber, and the air outlet device is used to discharge the airflow from the cleaning chamber.

8. The cleaning apparatus according to claim 7, characterized in that, The air intake device includes an air intake duct and an air jet structure connected to the air intake duct. The air jet structure is used to spray gas from the air intake duct toward the cleaning chamber.

9. The cleaning apparatus according to claim 8, characterized in that, It also includes a first control valve and a second control valve for controlling gas flow. The air inlet pipe includes a first air inlet pipe and a second air inlet pipe. The first control valve is disposed between the first air inlet pipe and the jet structure. The second control valve is disposed between the second air inlet pipe and the jet structure.

10. The cleaning apparatus according to claim 8, characterized in that, The jet structure includes multiple through holes communicating with the cleaning chamber.

11. The cleaning apparatus according to claim 1, characterized in that, It also includes a first robotic arm, which is connected to the first nozzle and is used to move the first nozzle above the fixing device.

12. The cleaning apparatus according to claim 1, characterized in that, It also includes a second nozzle, which is disposed in the cleaning chamber. The second nozzle has a fourth liquid line and a fifth liquid line inside. The fourth liquid line is used to spray a third cleaning liquid onto the object to be cleaned, and the fifth liquid line is used to spray a fourth cleaning liquid onto the object to be cleaned.

13. The cleaning apparatus according to claim 12, characterized in that, It also includes a second robotic arm, which is connected to the second nozzle and is used to move the second nozzle above the fixing device.

14. A cleaning method, characterized in that, include: Provide items to be cleaned; Provide a cleaning chamber; The object to be cleaned is controlled to enter the cleaning chamber, and a first cleaning liquid and an inert gas are sprayed onto the object to be cleaned. The spraying direction of the inert gas includes a first direction that is the same as the spraying direction of the first cleaning liquid and a second direction that forms a preset angle with the spraying direction of the first cleaning liquid. The preset angle is greater than 0 degrees and less than or equal to 90 degrees. The second cleaning liquid and the inert gas are sprayed onto the object to be cleaned, with the spraying direction of the second cleaning liquid being the same as that of the first cleaning liquid.

15. The cleaning method according to claim 14, characterized in that, After the object to be cleaned is controlled to enter the cleaning chamber, and before the first cleaning liquid and inert gas are sprayed onto the object to be cleaned, the method further includes: introducing nitrogen gas into the cleaning chamber.

16. The cleaning method according to claim 14, characterized in that, After spraying the second cleaning liquid and the inert gas onto the object to be cleaned, the process further includes: A drying liquid and an inert gas are sprayed onto the object to be cleaned, wherein the spraying direction of the drying liquid is the same as the spraying direction of the first cleaning liquid.

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