DEVICE AND METHOD FOR CLEANING SEMICONDUCTOR WAFTS

Abstract

The present disclosure describes a cleaning system that uses a cleaning fluid generated by a cooling system. The cleaning system comprises a cooling system configured to generate a cleaning fluid, a control system configured to control the temperature of the cleaning fluid, a wafer holder configured to hold and rotate a wafer, a first nozzle above the wafer configured to spray the cleaning fluid onto an upper surface of the wafer, and a second nozzle below the wafer configured to spray the cleaning fluid onto a lower surface of the wafer.

Description

CROSS-REFERENCE TO RELATED REGISTRATION

[0001] This application claims priority over the preliminary US patent application No. 63 / 715,401 entitled “Apparatus and Method for Cleaning Semiconductor Wafer”, filed on November 1, 2024, which is incorporated by reference into the present application. BACKGROUND

[0002] With advances in semiconductor technology, the demand for higher storage capacity, faster processing systems, increased performance, and lower costs has grown. To meet these demands, the semiconductor industry is continuously miniaturizing the dimensions of semiconductor devices, such as metal-oxide-semiconductor field-effect transistors (MOSFETs), including planar MOSFETs, fin field-effect transistors (FinFETs), gate-all-around field-effect transistors (GAAFETs), and nanostructured transistors. This miniaturization has increased the complexity of the semiconductor manufacturing process, and defects during manufacturing have also increased. A cleaning process is a critical step in the manufacturing process for purifying semiconductor wafers (e.g., silicon wafers). The yield of a silicon wafer is inversely proportional to the defect density (e.g., cleanliness and particle count) during wafer processing.One task of the wafer cleaning process is to remove chemical and particle contaminants without altering or damaging the wafer. BRIEF DESCRIPTION OF THE DRAWINGS

[0003] Aspects of this revelation are best understood by reference to the following detailed description in conjunction with the accompanying drawings. Fig. Figure 1 illustrates a cross-sectional view of a cleaning system according to some embodiments, which uses a cleaning fluid generated by a cooling system. The Fig. 2, Fig. 3 and Fig. Figure 4 illustrates partial cross-sectional views of a cooling system according to some embodiments. Fig. Figure 5 is a flowchart of a method for cleaning a wafer using a cleaning system according to some embodiments, which uses a cleaning fluid generated by a cooling system. Fig. Figure 6 is a flowchart of a cleaning process for cleaning a wafer with a cleaning fluid generated by a cooling system according to some embodiments. Fig. Figure 7 illustrates an example of a computer system in which various embodiments of the present disclosure may be implemented.

[0004] Illustrative embodiments are now described with reference to the accompanying drawings. In the drawings, identical reference numbers generally indicate identical, functionally similar, and / or structurally similar elements. DETAILED DESCRIPTION

[0005] The following disclosure provides many different embodiments or examples for implementing various features of the provided subject matter. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting. For example, forming a first element over a second element in the following description may include embodiments in which the first and second elements are formed in direct contact, and also embodiments in which additional features may be formed between the first and second elements, such that the first and second elements may not be in direct contact. As used herein, forming a first feature over a second feature means that the first feature is formed in direct contact with the second feature.Furthermore, the present disclosure may repeat reference numbers and / or symbols in the various examples. This repetition does not in itself dictate a relationship between the various described embodiments and / or configurations.

[0006] Furthermore, spatially relative terms such as "below," "under," "lower," "above," "upper," and the like may be used herein to facilitate discussion and describe the relationship of one element or feature to one or more other elements or features as illustrated in the figures. These spatially relative terms are intended to encompass, in addition to the orientation shown in the figures, various orientations of the device during its use or operation. The device may be oriented differently (rotated by 90 degrees or in other orientations), and the spatially relative descriptors used herein may likewise be interpreted accordingly.

[0007] It should be noted that references in the description to "an embodiment," "an exemplary embodiment," or "exemplary" indicate that the described embodiment may include a particular feature, structure, or property, but that not every embodiment necessarily includes that particular feature, structure, or property. Furthermore, such expressions do not necessarily refer to the same embodiment. If a particular feature, structure, or property is described in connection with one embodiment, it would be part of a person skilled in the art to have such a feature, structure, or property in connection with other embodiments, regardless of whether this is described in detail or not.

[0008] It is understood that the language or terminology used herein is for descriptive purposes and not for limitation, so that the terminology or language used in the existing description is to be interpreted by a person skilled in the field(s) in light of the teachings contained herein.

[0009] In some embodiments, the terms "approximately" and "essentially" may indicate a value of a given quantity that varies within 20% of the value (e.g., ±1%, ±2%, ±3%, ±4%, ±5%, ±10%, ±20% of the value). These values ​​are merely examples and are not intended to be limiting. The terms "approximately" and "essentially" may refer to a percentage of the values ​​as interpreted by a person skilled in the art in the relevant field, taking into account the teachings contained herein.

[0010] With the increasing demand for lower power consumption, higher performance, and smaller semiconductor devices, the dimensions of semiconductor devices on a wafer (e.g., silicon substrate) are being continuously reduced. This ongoing miniaturization of device dimensions and the increasing demand for device performance can necessitate various process improvements, which can present several challenges. For example, more layers of semiconductor devices and structures can be stacked on the wafer to improve device performance and reduce power consumption. The wafer temperature can rise after various semiconductor fabrication processes. This temperature increase can cause wafer deformation. If more layers of semiconductor structures are stacked on the wafer, this wafer deformation after these fabrication processes can be exacerbated.Increased wafer deformation can lead to defects such as an unevenly applied photoresist layer in subsequent processes, which can prevent photolithography tools from processing the deformed wafer.

[0011] A cleaning process can clean the front, back, and edges of a wafer after various semiconductor manufacturing processes. This cleaning process can be inline, using a room-temperature cleaning fluid such as deionized (DI) water. Although the wafer can be cooled by the room-temperature cleaning fluid during the cleaning process, the wafer temperature can still be high, causing warping and curling. This warping can make subsequent photolithography processes more difficult and reduce the yield of the semiconductor devices.

[0012] Various embodiments of the present disclosure provide systems and methods for cleaning a wafer with a cleaning fluid generated by a cooling system. In some embodiments, a cleaning system may include a cleaning device configured for cleaning a wafer with a cleaning fluid, a cooling system configured for generating the cleaning fluid, and a control system configured for controlling the temperature of the cleaning fluid. The cleaning device may include a wafer holder for holding and rotating the wafer, a first nozzle above the wafer, and a second nozzle below the wafer. The first nozzle may be configured to spray the cleaning fluid onto an upper surface of the wafer. The second nozzle may be configured to spray the cleaning fluid onto a lower surface of the wafer.In some embodiments, the cleaning system may also include temperature sensors at the first and second nozzles to monitor the temperature of the cleaning fluid. In some embodiments, the temperature of the cleaning fluid may range from approximately 5°C to approximately 15°C. In some embodiments, the cleaning fluid may cool the wafer and reduce wafer deformation. This may increase the uniformity of the photolithography layer subsequently deposited on the wafer. Increasing the uniformity of the photolithography layer may improve the yield of semiconductor devices on wafer 104. Additionally, the temperature of the cleaning fluid may be maintained above approximately 5°C to prevent wafer cracking due to rapid temperature changes during the cleaning process.

[0013] The Fig. Figures 1 to 4 illustrate partial cross-sectional views of various embodiments of a cleaning system 100 according to some embodiments, which uses a cleaning fluid generated by a cooling system. In some embodiments, as in Fig. As shown in Figure 1, the cleaning system 100 can comprise a cleaning device 110, a control unit 130, and a cooling system 140. In some embodiments, the cleaning device 110 can comprise a wafer holder 102, a wafer 104, nozzles 106, 108, and 120, temperature sensors 112, 114, and 116, lines 118 and 138, and valves 132 and 134. In some embodiments, the cleaning system 100 can be configured to clean the wafer 104 with a cleaning fluid 124 generated by the cooling system 140. The description of elements of the cooling system 100 in the Fig. Items 1 to 4, with the same notes, apply to all elements unless otherwise stated. Identical reference numbers generally indicate identical, functionally similar, and / or structurally similar elements.

[0014] In some embodiments, the wafer holder 102 can be an electrostatic wafer clamping device and configured to hold and rotate the wafer 104 during the cleaning process. In some embodiments, the wafer holder 102 can be configured as shown in Fig. Figure 1 shows pins 126 surrounding the wafer 104 to prevent it from slipping during the cleaning process. In some embodiments, the wafer holder 102 can rotate the wafer 104 during the cleaning process. In some embodiments, the arrow 128 indicates the direction of rotation of the wafer holder 102. In some embodiments, the wafer holder 102 can rotate the wafer 104 at a speed of approximately 100 revolutions per minute (rpm) to approximately 1000 rpm to distribute the cleaning fluid 124 over the wafer 104 and remove any residues and particles from its surface. If the speed exceeds approximately 1000 rpm, cracks may occur in the wafer, and semiconductor devices and structures on the wafer 104 may be damaged.If the speed is less than approximately 100 rpm, the cleaning fluid may not be distributed evenly over the wafer 104 and residues and particles may remain on the wafer 104 after the cleaning process.

[0015] In some embodiments, the wafer 104 can be a semiconductor wafer on whose surfaces semiconductor devices and structures, such as logic devices, memory devices, and interconnects, are formed. In some embodiments, the wafer 104 can comprise a semiconductor material, such as silicon. In some embodiments, the wafer 104 comprises a crystalline silicon substrate (e.g., a silicon wafer). In some embodiments, the wafer 104 comprises (i) an elemental semiconductor such as germanium; (ii) a compound semiconductor including silicon carbide, gallium arsenide, gallium phosphide, indium phosphide, indium arsenide, and / or indium antimonide; (iii) an alloy semiconductor including silicon germanium carbide, silicon germanium, gallium arsenic phosphide, and / or aluminum gallium arsenide; or (iv) a combination thereof. Furthermore, the wafer 104 can be doped according to design requirements (e.g.,p-substrate or n-substrate). In some embodiments, the wafer 104 can be doped with p-dopers (e.g., boron, indium, aluminum, or gallium) or n-dopers (e.g., phosphorus or arsenic).

[0016] In some embodiments, the wafer 104 can undergo various manufacturing processes, which may include tempering, deposition, or other high-temperature processes. After these high-temperature manufacturing processes, the wafer 104 may have a temperature greater than approximately 300 °C. In some embodiments, the high temperature of the wafer 104 exceeding approximately 300 °C can cause wafer deformation and warping, which can lead to further problems for subsequent lithography processes. In some embodiments, warping can cause the edge of the wafer 104 to bend upwards or downwards relative to the center of the wafer 104. In some embodiments, warping can result in a height difference d between the center and the edge of the wafer 104 of more than approximately 300 µm. A large height difference d (e.g.,A wafer warp height difference (greater than approximately 300 µm) can cause problems in subsequent lithography processes. In some embodiments, the height difference d of the wafer warp can range between approximately 300 µm and approximately 600 µm. In some embodiments, wafer cracks can occur and the semiconductor devices and structures on wafer 104 can be damaged if the height difference d is greater than approximately 600 µm. In some embodiments, a wafer warp does not cause problems for subsequent lithography processes if the height difference d is less than approximately 300 µm.

[0017] In some embodiments, cleaning fluid 124 can be used as in Fig. Figure 1 shows the cleaning fluid being sprayed through nozzle 120 onto an upper surface of the wafer 104 and through nozzles 106 and 108 onto a lower surface of the wafer 104. In some embodiments, the cleaning fluid 124 may contain cold DI water generated by the cooling system 140. In some embodiments, the cleaning fluid 124 may contain any suitable cleaning fluids, such as, but not limited to, DI water, ultrapure water, isopropyl alcohol (IPA), hydrogen peroxide, ammonium hydroxide, acids, acetone, methanol, or any combination thereof. In some embodiments, the cleaning fluid 124 flowing from nozzle 120 and nozzles 106 and 108 may contain the same cleaning fluid. In some embodiments, the cleaning fluid 124 flowing from nozzle 120 and nozzles 106 and 108 may contain different cleaning fluids.

[0018] In some embodiments, the temperature of the cleaning fluid 124 can be lower than room temperature. In some embodiments, the temperature of the cleaning fluid 124 can be in the range of approximately 5 °C to approximately 15 °C to reduce wafer warping. If the temperature of the cleaning fluid 124 is greater than approximately 15 °C, the cleaning fluid 124 may not be able to reduce the height difference d of the wafer warping to less than approximately 300 µm. If the temperature of the cleaning fluid 124 is lower than approximately 5 °C, the cleaning process can cause a rapid temperature change of the wafer 104 and lead to wafer cracking. In some embodiments, the temperature of the cleaning fluid 124 can be in the range of approximately 8 °C to approximately 10 °C to further reduce the height difference d of the wafer warping and reduce wafer cracking.In some embodiments, the wafer 104 can exhibit essentially no deformation or cracking after the cleaning process if the temperature of the cleaning fluid 124 is in the range of approximately 8 °C to approximately 10 °C. By lowering the temperature of the cleaning fluid 124 by means of the cooling system 140, the deformation and warping of the wafer 104 can be reduced, the uniformity of the subsequent photolithography layer on the wafer 104 can be improved, and the yield of the semiconductor devices on the wafer 104 can be increased.

[0019] In some embodiments, the nozzle 120 can be arranged above the top surface of the wafer 104, and the nozzles 106 and 108 can be arranged below the bottom surface of the wafer 104. In some embodiments, the top surface of the wafer 104 can be a front surface and may have various semiconductor devices and structures. In some embodiments, the bottom surface of the wafer 104 can be a back surface and may have fewer or substantially no semiconductor devices. In some embodiments, the nozzle 120 can move across the top surface of the wafer 104 while spraying cleaning fluid 124 onto the top surface of the wafer 104 at a preset flow rate. As in Fig. As shown in Figure 1, the nozzle 120 can, for example, move during a cleaning cycle from the edge of the wafer 104, such as position A, to the center of the wafer 104, such as position B, and back to a starting position (also referred to as "home"), such as position C. In some embodiments, the movement of the nozzle 120 during the cleaning cycle can be indicated by the arrow 122. In some embodiments, the nozzles 106 and 108 can be moved as shown in Figure 1. Fig. 1 shown on opposite sides of the wafer holder 102 under the wafer 104.

[0020] In some embodiments, nozzles 106 and 108 can spray the cleaning fluid 124 onto the lower surface of the wafer 104 at a preset flow rate. In some embodiments, nozzles 106 and 108 cannot move while spraying the cleaning fluid 124. In some embodiments, the wafer holder 102 can hold and rotate the wafer 104 while nozzles 120, 106, and 108 spray the cleaning fluid 124 onto the upper and lower surfaces of the wafer 104. Although in Fig. Figure 1 shows three nozzles 120, 106 and 108, the cleaning device 110 can have any number of nozzles to spray the cleaning fluid 124 onto the wafer 104.

[0021] In some embodiments, the cleaning cycle may include additional steps, and each step may last from approximately 5 seconds to approximately 15 seconds. In some embodiments, the cleaning cycle may include 8 to 10 steps. In some embodiments, the steps in the cleaning cycle may include using different nozzles, such as nozzles 120, 106, and 108, to clean different areas of the wafer 104. In some embodiments, the steps in the cleaning cycle may include using a single nozzle, such as nozzle 120, to clean different areas of the wafer 104. In some embodiments, the steps in the cleaning cycle may include dispensing cleaning fluid 124 at different flow rates. In some embodiments, the wafer 104 may be rotated while being cleaned with cleaning fluid 124.In some embodiments, the wafer 104 can be turned upside down for cleaning during the cleaning cycle. In some embodiments, the cleaning fluid 124 can be used in each step of the cleaning cycle.

[0022] In some embodiments, the temperature sensors 112, 114 and 116 can be used as shown in Fig. The temperature sensors 112, 114, and 116 are arranged accordingly at the nozzles 120, 106, and 108, as shown in Figure 1. In some embodiments, the temperature sensors 112, 114, and 116 can measure the temperature of the cleaning fluid 124 flowing out of the nozzles 120, 106, and 108, respectively. In some embodiments, the controller 130 can control the cooling system 140 to decrease or increase the temperature of the cleaning fluid 124 within a specific range if the temperature of the cleaning fluid 124 is outside a specific range, such as approximately 5 °C to approximately 15 °C. Although in Fig. Figure 1 shows three temperature sensors 112, 114 and 116. The cleaning device 110 can have any number of temperature sensors to measure the temperature of the cleaning fluid 124 sprayed onto the wafer 104.

[0023] In some embodiments, the temperature of the cleaning fluid 124 flowing out of nozzle 120 can differ from the temperature of the cleaning fluid 124 flowing out of nozzles 106 and 108. In some embodiments, the cleaning fluid 124 discharged from nozzle 120 onto the upper surface of the wafer 104 can have a first temperature. The cleaning fluid 124 discharged from nozzles 106 and 108 onto the lower surface of the wafer 104 can have a second temperature. In some embodiments, the first temperature can be greater than or substantially equal to the second temperature. In some embodiments, the first temperature can be less than the second temperature. In some embodiments, the temperature difference between the first temperature and the second temperature can be in the range of approximately 0 °C to approximately 5 °C.If the temperature difference is greater than approximately 5 °C, the wafer 104 may crack and the semiconductor devices and structures on the wafer 104 may be damaged. In some embodiments, the temperature difference of the cleaning fluid 124 may be caused by different lines 118 and 138 used to supply the cleaning fluid 124. In some embodiments, the cooling system 140 may separately control the temperature of the first cleaning fluid 124 supplied to nozzle 120 and the temperature of the second cleaning fluid 124 supplied to nozzles 106 and 108.

[0024] In some embodiments, the cleaning fluid 124 can be used as in Fig. The cleaning fluid 124 is supplied via line 118 to nozzles 120 and via line 138 to nozzles 106 and 108. In some embodiments, line 118 may include a valve 132 between the cooling system 140 and nozzle 120. Line 138 may include a valve 134 between the cooling system 140 and nozzles 106 and 108. In some embodiments, valves 132 and 134 may limit or adjust the flow rate of the cleaning fluid 124 in lines 118 and 138, respectively. In some embodiments, valves 132 and 134 may be controlled by the controller 130 to adjust the flow rate of the cleaning fluid 124. In some embodiments, the flow rate of the cleaning fluid 124 may be in the range of approximately 1 liter per minute (l / min) to approximately 8 l / min.In some embodiments, particles can accumulate in the cleaning fluid 124, and particles and residues can remain on the wafer 104 after the cleaning process if the flow rate is less than approximately 1 l / min. Furthermore, the temperature of the cleaning fluid 124 can rise. If the flow rate is greater than approximately 8 l / min, the cleaning fluid 124 sprayed onto the wafer 104 can damage the semiconductor devices and structures on the wafer 104. In some embodiments, the flow rate of the cleaning fluid 124 in line 118 can differ from, or be substantially the same as, the flow rate of the cleaning fluid 124 in line 138.

[0025] In some embodiments, the control 130 can be configured as in Fig. Figure 1 shows the cleaning device 110 and the cooling system 140 connected to it. In some embodiments, the controller 130 can monitor the temperature of the cleaning fluid 124 flowing out of the nozzles 120, 106, and 108 using the temperature sensors 112, 114, and 116. In some embodiments, the controller 130 can control the flow rate of the cleaning fluid 124 in the lines 118 and 138 using the valves 132 and 134. In some embodiments, the controller 130 can adjust the temperature of the cleaning fluid 124 using a cooling system 140. In some embodiments, the controller 130 can control the wafer holder 102 such that it holds and rotates the wafer 104 while the cleaning fluid 124 is dispensed onto the wafer 104. In some embodiments, the control unit 130 can control the nozzle 120 such that it moves between position A, position B and position C.In some embodiments, the controller 130 can communicate with the cleaning device 110 and the cooling system 140 via wired communication channels. In some embodiments, the controller 130 can communicate with the cleaning device 110 and the cooling system 140 via wireless communication channels. One embodiment of the controller 130 is shown in . Fig. 7 described in detail.

[0026] In some embodiments, the cooling system 140 can be used as in Fig. Figure 1 shows the cleaning device 110 connected to the control unit 130. In some embodiments, the cooling system 140 can generate the cleaning fluid 124 and supply it to the cleaning device 110. In some embodiments, the cooling system 140 can be controlled by the control unit 130 to adjust the temperature of the cleaning fluid 124. In some embodiments, the cooling system 140 can be operated as shown in Figure 1. Fig. Figure 2 shows a cooling tank 242, a cleaning fluid line 246, and a coolant line 244. In some embodiments, the cooling tank 242 can be filled with a coolant such as glycol. In some embodiments, the coolant in the cooling tank 242 can absorb heat from the cleaning fluid line 246 and transfer heat to the coolant line 244.

[0027] In some embodiments, the cleaning fluid line 246 can generate cleaning fluid 124 from the room temperature cleaning fluid 224. In some embodiments, the room temperature cleaning fluid 224 can be produced as in Fig. The cleaning fluid 243 is shown flowing into the cleaning fluid line 246. The coolant in the cooling tank 242 can absorb the heat of the room-temperature cleaning fluid 224 and lower its temperature. In some embodiments, the cleaning fluid line 246 may have a Teflon tube, and the room-temperature fluid 224 may be ultrapure water. In some embodiments, the coolant 243 can flow through the coolant line 244 and dissipate the heat from the coolant in the cooling tank 242.

[0028] In some embodiments, a temperature sensor 248 can be used as in Fig. The temperature sensor 248 is arranged at an outlet of the cleaning fluid line 246 to measure the temperature of the generated cleaning fluid 124. In some embodiments, the controller 130 can monitor the temperature of the generated cleaning fluid 124 using the temperature sensor 248. In some embodiments, the controller 130 can control the temperature of the cleaning fluid 124 flowing out of the cleaning fluid line 246 by adjusting a flow rate of the coolant 243 in the coolant line 244. In some embodiments, the cooling system 140 can include a temperature controller (not shown) to control the flow rates of the room-temperature cleaning fluid 224 and the cleaning fluid 124 in order to control the temperature of the cleaning fluid 124 flowing out of the cleaning fluid line 246.

[0029] In some embodiments, the temperature of the cleaning fluid 124 for the cleaning device 110 can be in the range of approximately 5 °C to approximately 15 °C to reduce wafer warping. If the temperature of the cleaning fluid 124 is greater than approximately 15 °C, it may not be able to reduce the height difference d of the wafer warping below approximately 300 µm. If the temperature of the cleaning fluid 124 is less than approximately 5 °C, the cleaning process may cause a rapid temperature change of the wafer 104 and lead to wafer cracking. In some embodiments, the temperature of the cleaning fluid 124 can be in the range of approximately 8 °C to approximately 10 °C to further reduce the height difference d of the wafer warping and thus minimize wafer cracking.In some embodiments, the wafer 104 can exhibit essentially no deformation or cracking after the cleaning process if the temperature of the cleaning fluid 124 is in the range of approximately 8 °C to approximately 10 °C. The cleaning fluid 124 provided by the cooling system 140 can reduce the deformation and warping of the wafer 104, improve the uniformity of the subsequent photolithography layer on the wafer 104, and increase the yield of the semiconductor devices on the wafer 104.

[0030] In some embodiments, sections of the cleaning fluid line 246 and the coolant line 244 can be configured as shown in Fig. 2 shown in the cooling tank 242. In some embodiments, the sections of the cleaning fluid line 246 and the coolant line 244 can be bent as shown in Fig. Figure 3 shows that the cooling tank 242 is spiral-shaped. In some embodiments, the spiral shape can increase the contact area between the coolant and the cleaning fluid line 246, as well as between the coolant and the coolant line 244. Increasing the contact area can improve the heat exchange efficiency of the cooling system 140 and the temperature control of the cleaning fluid 124. In some embodiments, the sections of the cleaning fluid line 246 and the coolant line 244 in the cooling tank 242 can have other suitable configurations to increase the contact area.

[0031] In some embodiments, the diameter 244d of the coolant line 244 can be in the range of approximately 5 mm to approximately 10 mm for improved temperature control of the cleaning fluid 124. If the diameter 244d is less than approximately 5 mm, the temperature of the cleaning fluid 124 may be approximately 15 °C higher, and the cleaning fluid 124 may not be able to reduce wafer warping. If the diameter 244d is greater than approximately 10 mm, the temperature of the cleaning fluid 124 may be less than approximately 5 °C, and the cleaning fluid 124 may cause cracks in the wafer and damage to the semiconductor devices and structures on the wafer 104.

[0032] In some embodiments, the diameter 246d of the cleaning fluid line 246 can range from approximately 5 mm to approximately 20 mm. In some embodiments, the pressure of the cleaning fluid 124 can range from approximately 2 kg / cm² to approximately 4 kg / cm². In some embodiments, the cooling system 140 may not provide a sufficient quantity of the cleaning fluid 124 for the cleaning process if the diameter 246d is less than approximately 5 mm or the pressure of the cleaning fluid 124 is less than approximately 2 kg / cm². In some embodiments, the cleaning fluid 124 may cause cracks in the wafer and damage the semiconductor devices and structures on the wafer 104 if the diameter 246d is greater than approximately 20 mm or the pressure of the cleaning fluid 124 is greater than approximately 4 kg / cm².

[0033] In some embodiments, the cleaning fluid line 246 and the coolant line 244 can be arranged as shown in the Fig. 2 and Fig. 3 shown on opposite sides of the cooling tank 242. In some embodiments, the cleaning fluid line 246 and the coolant line 244 can be arranged as shown in Fig. 4 shown on the same side of the cooling tank 242. In some embodiments, the cleaning fluid line 246 and the coolant line 244 can be arranged in other suitable configurations to produce cleaning fluid 124.

[0034] Fig. Figure 5 is a flowchart of a process 500 for a cleaning system for cleaning a wafer with a cleaning fluid generated by a cooling system according to some embodiments. The process 500 is not limited to the cleaning system 100 and may also be applicable to other systems that would benefit from the cleaning fluid. Additional steps may be performed between various steps of the process 500, and they may be omitted solely for the sake of clarity and ease of description. Additional steps may be provided before, during, and / or after the process 500; one or more of these additional steps are briefly described herein. Furthermore, not all operations may be necessary to carry out the disclosure described herein. Additionally, some of the operations may be performed simultaneously or in a different order than shown. Fig. 5. In some embodiments, one or more other operations can be performed in addition to or instead of the operations currently described. For illustrative purposes, the operations shown in Figure 5 are shown in Figure 5. Fig. 5 illustrated work processes with reference to those in the Fig. Figures 1 to 4 illustrate exemplary embodiments.

[0035] With reference to Fig. 5. Procedure 500 begins with work step 510 and the loading of a wafer into a cleaning device. For example, wafer 104 can be loaded as in Fig. 1 shown in the cleaning device 110. In some embodiments, the wafer holder 102 can be configured to hold and rotate the wafer 104. In some embodiments, the wafer holder 102 can be configured as shown in Fig. Figure 1 shows pins 126 surrounding the wafer 104 to prevent it from slipping during a cleaning process. In some embodiments, the wafer holder 102 can rotate the wafer 104 at a speed of approximately 100 rpm to approximately 1000 rpm to distribute the cleaning fluid 124 over the wafer 104 and remove any residues and particles from its surface.

[0036] With reference to Fig. In process 520, a cleaning fluid is produced using a cooling system, resulting in a temperature below room temperature. For example, cleaning fluid 124 can be used as described in the Fig. Figures 1 to 4 are shown to be generated by the cooling system 140 and have a temperature below room temperature. In some embodiments, the cooling system 140 can generate the cleaning fluid 124 from the room-temperature cleaning fluid 224. In some embodiments, the cooling system 140 can include the cooling tank 242, the coolant line 244, and the cleaning fluid line 246, as shown in the figures. Fig. Figures 2 to 4 show the system for generating the cleaning fluid 124. In some embodiments, the temperature sensor 248 can be arranged at an outlet of the cleaning fluid line 246 to measure the temperature of the generated cleaning fluid 124. In some embodiments, the controller 130 can be configured as shown in the figures. Fig. Figures 1 to 4 show the use of the temperature sensor 248 to monitor and control the temperature of the generated cleaning fluid 124.

[0037] In some embodiments, the temperature of the cleaning fluid 124 for the cleaning device 110 can be in the range of approximately 5 °C to approximately 15 °C to reduce wafer warping. If the temperature of the cleaning fluid 124 is greater than approximately 15 °C, it may not be able to reduce the height difference d of the wafer warping below approximately 300 µm. If the temperature of the cleaning fluid 124 is less than approximately 5 °C, the cleaning process may cause a rapid temperature change of the wafer 104 and lead to wafer cracking. In some embodiments, the temperature of the cleaning fluid 124 can be in the range of approximately 8 °C to approximately 10 °C to further reduce the height difference d of the wafer warping and thus minimize wafer cracking.In some embodiments, the wafer 104 can exhibit essentially no deformation or cracking after the cleaning process if the temperature of the cleaning fluid 124 is in the range of approximately 8 °C to approximately 10 °C. The cleaning fluid 124 provided by the cooling system 140 can reduce the deformation and warping of the wafer 104, improve the uniformity of the subsequent photolithography layer on the wafer 104, and increase the yield of the semiconductor devices on the wafer 104.

[0038] With reference to Fig. In process 530, the cleaning fluid is supplied to a first nozzle above the wafer and a second nozzle below the wafer. As in Fig. As shown in Figure 1, the cleaning fluid 124 can, for example, be supplied to nozzle 120 above wafer 104 and to nozzles 106 and 108 below wafer 104. In some embodiments, the cleaning fluid 124 can be supplied to nozzle 120 via line 118 and valve 132. In some embodiments, the cleaning fluid 124 can be supplied to nozzles 106 and 108 via line 138 and valve 134. In some embodiments, the controller 130 can control a flow rate of the cleaning fluid 124, which is supplied accordingly via valves 132 and 134 to nozzle 120 and nozzles 106 and 108. In some embodiments, the flow rate of the cleaning fluid 124 can be in the range of approximately 1 l / min to approximately 8 l / min.In some embodiments, particles can accumulate in the cleaning fluid 124, and particles and residues can remain on the wafer 104 after the cleaning process if the flow rate is less than approximately 1 l / min. Furthermore, the temperature of the cleaning fluid 124 can rise. If the flow rate is greater than approximately 8 l / min, the cleaning fluid 124 sprayed onto the wafer 104 can damage the semiconductor devices and structures on the wafer 104. In some embodiments, the flow rate of the cleaning fluid 124 in line 118 can differ from, or be substantially the same as, the flow rate of the cleaning fluid 124 in line 138.

[0039] With reference to Fig. In work step 540, the upper surface of the wafer is cleaned with the cleaning fluid using the first nozzle, and the lower surface of the wafer is cleaned with the cleaning fluid using the second nozzle. As in Fig. As shown in Figure 1, the upper surface of the wafer 104 can be cleaned, for example, with the cleaning fluid 124 using the nozzle 120, and the lower surface of the wafer 104 can be cleaned with the cleaning fluid 124 using the nozzles 106 and 108. In some embodiments, the nozzle 120 can move across the upper surface of the wafer 104 while the upper surface of the wafer 104 is being cleaned with the cleaning fluid 124. For example, the nozzle 120 can move as shown in Fig. Figure 1 shows the nozzle moving during a cleaning cycle from the edge of the wafer 104, such as position A, to the center of the wafer 104, such as position B, and back to a starting position, such as position C. In some embodiments, the controller 130 can control the movement of the nozzle 120 as indicated by arrow 122 during the cleaning cycle.

[0040] In some embodiments, nozzles 106 and 108 can be configured as shown in Fig. The nozzles 106 and 108 are arranged on opposite sides of the wafer holder 102 and spray cleaning fluid 124 onto the lower surface of the wafer 104. In some embodiments, the nozzles 106 and 108 do not move while cleaning the lower surface of the wafer 104 with cleaning fluid 124. In some embodiments, the nozzles 106, 108, and 108 can clean the upper and lower surfaces of the wafer 104 with cleaning fluid 124 while the wafer holder 102 holds and rotates the wafer 104. In some embodiments, the wafer holder 102 can rotate the wafer 104 at a speed of approximately 100 rpm to approximately 1000 rpm to distribute the cleaning fluid 124 over the wafer 104 and remove any residues and particles from the upper and lower surfaces of the wafer 104.

[0041] In some embodiments, the operation 540 can be performed in Fig. 6 will be described in more detail. As in Fig. As shown in Figure 6, the cleaning process can begin in operation 610. In some embodiments, the cleaning device 110 can be initialized for the cleaning process in operation 610. In some embodiments, the cleaning device 110 can be initialized as shown in Figure 6. Fig. 1 shown in work process 610, move the nozzle 120 as indicated by position A from the starting position C to the edge of the wafer 104.

[0042] The cleaning process can be performed in operation 620. In some embodiments, the cleaning process can comprise one or more cleaning cycles. In some embodiments, each cleaning cycle can comprise operations 622, 624, 626, 627, and 628. In operation 622, the process parameters for the cleaning process can be predicted by the controller 130. In some embodiments, the process parameters can include the temperature of the cleaning fluid 124, the flow rate of the cleaning fluid 124, the rotational speed of the wafer holder 102, and other suitable process parameters. In some embodiments, the process parameters can be predicted based on previous wafer warping data after the cleaning process.In some embodiments, previous wafer warping data can be acquired after cleaning the front side with cleaning fluid 124, cleaning the back side with cleaning fluid 124, and cleaning both the front and back sides with cleaning fluid 124. In some embodiments, the process parameters can be predicted based on previous semiconductor fabrication processes performed on the wafer 104. In some embodiments, the process parameters can be predicted using a machine learning model, a neural network model, or other suitable data models created with big data mining.

[0043] In operation 624, the controller 130 can control the cleaning device 110 such that the cleaning process is carried out with the predicted process parameters. In some embodiments, the controller 130 can control the temperature of the cleaning fluid 124, the flow rate of the cleaning fluid 124, the rotational speed of the wafer holder 102, and other parameters of the cleaning device 110 according to the predicted process parameters.

[0044] In operation 626, the controller 130 can analyze the wafer curvature data of wafer 104 after the cleaning process. In some embodiments, the wafer curvature data can be measured in subsequent inline measuring tools after the cleaning process. In step 627, the controller 130 can check the wafer curvature data of wafer 104. If the wafer curvature data of wafer 104 is within specifications, for example, if the height difference d between the center and the edge of wafer 104 is less than approximately 300 µm, the next cleaning cycle can be continued for further wafers with the predicted process parameters. If the wafer curvature data of wafer 104 is outside specifications, for example, if the height difference d is greater than approximately 300 µm, the controller 130 can stop the cleaning process and the cleaning device 110 for inspection by a user.

[0045] In operation 630, the controller 130 can terminate the cleaning process. In some embodiments, the cleaning process can end when all wafers have been cleaned. In some embodiments, the cleaning process can end when the cleaning device 110 is stopped for inspection and maintenance. In some embodiments, the controller 130 can stop the rotation of the wafer holder 102 and reduce the flow rate of the cleaning fluid 124 to approximately 1 l / min after the cleaning process has ended.

[0046] Fig. Figure 7 illustrates an exemplary computer system 700 according to some embodiments, in which various embodiments of the present disclosure may be implemented. The computer system 700 can be any known computer capable of performing the functions and operations described herein. For example, and without limitation, the computer system 700 can be capable of controlling the cooling system 140 to generate cleaning fluid 124 and controlling the cleaning device 110 to clean the wafer 104 with the cleaning fluid 124. The computer system 700 can be an example of the control 130 to perform, for example, one or more operations in methods 500 and 600, which describe an exemplary procedure for the cleaning system 100 to clean the wafer 104 with the cleaning fluid 124 generated by the cooling system 140.

[0047] The Computer System 700 has one or more processors (also called central processing units or CPUs), such as a Processor 704. The Processor 704 is connected to a communication infrastructure or bus 706. The Computer System 700 also has input / output devices 703, such as monitors, keyboards, pointing devices, etc., which communicate with a communication infrastructure or bus 706 via input / output interfaces 702. A system control tool can use the input / output device(s) 703 to send instructions for implementing functions and operations described herein, such as Procedure 500 of Fig. 5, received. The computer system 700 also includes a main or primary memory 708, such as main memory (RAM). The main memory 708 may have one or more cache levels. Control logic (e.g., computer software) and / or data are stored in the main memory 708. In some embodiments, the control logic (e.g., computer software) and / or data may be one or more of the cache levels described above in relation to method 500. Fig. exhibit 5 described work processes.

[0048] The Computer System 700 may also include one or more secondary storage devices or storage 710. The secondary storage 710 may, for example, include a hard disk drive 712 and / or a removable storage device or drive 714. The removable storage drive 714 may be a floppy disk drive, a magnetic tape drive, a compact disk drive, an optical storage device, a tape backup device, and / or another storage device / drive.

[0049] The removable storage drive 714 can interact with a removable storage unit 718. The removable storage unit 718 comprises a storage device usable or readable by a computer, on which computer software (control logic) and / or data are stored. The removable storage unit 718 can be a floppy disk, magnetic tape, compact disc, DVD, optical storage disk, and / or other computer data storage device. The removable storage drive 714 reads from and / or writes to the removable storage unit 718 in a known manner.

[0050] In some embodiments, the secondary storage device 710 may include other means, instruments, or approaches to enable the computer system 700 to access computer programs and / or other instructions and / or data. Such means, instruments, or approaches may, for example, include a removable storage device 722 and an interface 720.

[0051] Examples of the removable storage unit 722 and the interface 720 may include a program cartridge and a cartridge interface (such as those found in video game devices), a removable memory chip (such as an EPROM or PROM) and an associated socket, a memory stick and a USB connector, a memory card and an associated memory card slot, and / or any other removable storage unit and associated interface. In some embodiments, the secondary storage 710, the removable storage unit 718, and / or the removable storage unit 722 may include one or more of the above described in relation to method 500. Fig. The 5 described work processes are included.

[0052] The Computer System 700 may also include a communication or network interface 724. The communication interface 724 enables the Computer System 700 to communicate and interact with any combination of remote devices, remote networks, remote units, etc. (individually and collectively designated by reference 728). For example, the communication interface 724 may enable the Computer System 700 to communicate with remote devices 728 over a communication path 726, which may be wired and / or wireless and may include any combination of LANs, WANs, the Internet, etc. Control logic and / or data may be transmitted to and from the Computer System 700 over the communication path 726.

[0053] The operations described above can be implemented in several configurations and architectures. Therefore, some or all of the operations described above—e.g., Method 500 in Fig.5 - be implemented in hardware, software, or both. In some embodiments, a tangible device or tangible manufactured item, including a tangible medium usable by or readable by a computer, on which control logic (software) is stored, is also referred to herein as a computer program product or program storage device. This includes, without limitation, the computer system 700, the main memory 708, the secondary memory 710, and the removable storage units 718 and 722, as well as tangible manufactured items embodying any combination of the foregoing elements. When such control logic is executed by one or more data processing devices (such as the computer system 700), it causes such data processing devices to operate as described herein.

[0054] Various embodiments of the present disclosure provide systems and methods for cleaning the wafer 104 with the cleaning fluid 124 generated by the cooling system 140. In some embodiments, the cleaning system 100 may include a cleaning device 110 configured for cleaning the wafer 104 with the cleaning fluid 124, a cooling system 140 configured for generating cleaning fluid 124, and a control 130 configured for controlling the temperature of the cleaning fluid 124. The cleaning device 110 may include the wafer holder 102 configured for holding and rotating the wafer 104, the nozzle 120 above the wafer 104, and the nozzles 106 and 108 below the wafer 104. The nozzle 120 may be configured to spray the cleaning fluid 124 onto an upper surface of the wafer 104.Nozzles 106 and 108 can be configured to spray the cleaning fluid 124 onto a lower surface of the wafer 104. In some embodiments, the cleaning system 100 can further include temperature sensors 112, 114, and 116 at nozzles 120, 106, and 108 to monitor the temperature of the cleaning fluid 124. In some embodiments, the temperature of the cleaning fluid 124 can be in the range of approximately 5 °C to approximately 15 °C. In some embodiments, the cleaning fluid 124 can cool the wafer 104 and reduce wafer deformation. This can increase the uniformity of the photolithography layer subsequently deposited on the wafer 104. Increasing the uniformity of the photolithography layer can improve the yield of semiconductor devices on the wafer 104.Additionally, the temperature of the cleaning fluid 124 can be kept above approximately 5 °C to avoid wafer cracks due to rapid temperature changes of the wafer 104 during the cleaning process.

[0055] In some embodiments, a device comprises a wafer holder configured to hold and rotate a wafer, a first nozzle above the wafer configured to spray a first cleaning fluid onto an upper surface of the wafer, and a second nozzle below the wafer configured to spray a second cleaning fluid onto a lower surface of the wafer. The first cleaning fluid is generated by a cooling system, and its temperature is below room temperature. The second cleaning fluid is also generated by the cooling system, and its temperature is below room temperature.

[0056] In some embodiments, a method comprises loading a wafer into a cleaning device, generating, with a cooling system, a cleaning fluid at a temperature below room temperature, conveying the cleaning fluid to a first nozzle above the wafer and a second nozzle below the wafer, and cleaning an upper surface of the wafer with the cleaning fluid using the first nozzle and a lower surface of the wafer with the cleaning fluid using the second nozzle.

[0057] In some embodiments, a system comprises a cooling system configured to generate a cleaning fluid, a controller configured to control the temperature of the cleaning fluid, a wafer holder configured to hold and rotate a wafer, a first nozzle above the wafer configured to spray the cleaning fluid onto an upper surface of the wafer, and a second nozzle below the wafer configured to spray the cleaning fluid onto a lower surface of the wafer.

[0058] It should be noted that the Detailed Description section, and not the Summary of Disclosure section, is to be used to interpret the claims. The Summary of Disclosure section may describe one or more, but not all, possible embodiments of the present disclosure as intended by the inventor(s) and is therefore not intended to limit the attached claims in any way.

[0059] The foregoing disclosure describes features of several embodiments so that the person skilled in the art can better understand the aspects of the present disclosure. It will be obvious to the person skilled in the art that they can readily use the present disclosure as a basis for designing or modifying other processes and structures to achieve the same purposes and / or the same advantages as the embodiments introduced herein. The person skilled in the art will also realize that such equivalent interpretations do not deviate from the meaning and scope of the present disclosure, and that they can make various changes, substitutions, and modifications therein without deviating from the meaning and scope of the present disclosure. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] US 63 / 715,401

[0001]

Claims

[1] Device comprising: a wafer holder designed to hold and rotate a wafer; a first nozzle above the wafer, which is configured to spray a first cleaning fluid onto an upper surface of the wafer, wherein the first cleaning fluid is generated by a cooling system and the first temperature of the first cleaning fluid is below room temperature; and a second nozzle under the wafer, which is configured to spray a second cleaning fluid onto a lower surface of the wafer, wherein the second cleaning fluid is generated by the cooling system and the temperature of the second cleaning fluid is below room temperature. [2] Device according to claim 1, further comprising: a third nozzle under the wafer, which is configured to spray the second cleaning fluid onto the lower surface of the wafer, with the second and third nozzles located on opposite sides of the wafer holder. [3] Device according to claim 1 or 2, further comprising: a line which connects the first nozzle to the cooling system, wherein the line is configured to supply the first cleaning fluid to the first nozzle. [4] Device according to claim 3, further comprising: a valve on the line that is set up to control the flow rate of the first cleaning fluid supplied to the first nozzle. [5] Device according to one of claims 1 to 4, further comprising: a line which connects the second nozzle to the cooling system, wherein the line is configured to supply the second cleaning fluid to the second nozzle. [6] Device according to any one of claims 1 to 5, wherein each of the first and second temperatures is in the range of approximately 5 °C to approximately 15 °C. [7] Device according to any one of claims 1 to 6, further comprising: a first temperature sensor, which is arranged and configured at the first nozzle to measure the first temperature; and a second temperature sensor, which is positioned at the second nozzle and configured to measure the second temperature. [8] Device according to any one of claims 1 to 7, wherein the difference between the first temperature and the second temperature is in the range of approximately 0 °C to approximately 5 °C. [9] Device according to any one of claims 1 to 8, wherein the first and the second cleaning fluid comprise deionized water produced by the cooling system. [10] Procedures, including: Loading a wafer into a cleaning device; Generate, with a cooling system, a cleaning fluid with a temperature below room temperature; Supplying the cleaning fluid to a first nozzle above the wafer and a second nozzle below the wafer; and Cleaning an upper surface of the wafer with the cleaning fluid using the first nozzle and a lower surface of the wafer with the cleaning fluid using the second nozzle. [11] The method of claim 10, further comprising: Measuring the temperature of the cleaning fluid with a temperature sensor at the first nozzle. [12] Method according to claim 10 or 11, further comprising: Controlling the flow rate of the cleaning fluid using a valve on a line connected to the first nozzle. [13] Method according to any one of claims 10 to 12, comprising cleaning the upper surface of the wafer: Rotating the wafer using a wafer holder; Spraying the cleaning fluid onto the top surface of the wafer; and Moving the first nozzle from one edge of the wafer to the center of the wafer while the wafer is rotated. [14] Method according to any one of claims 10 to 13, wherein generating the cleaning fluid with the cooling system comprises controlling the temperature of the cleaning fluid between approximately 5 °C and approximately 15 °C. [15] Method according to any one of claims 10 to 14, further comprising measuring the temperature of the cleaning fluid flowing out of the cooling system with a temperature sensor. [16] System, having: a cooling system designed to produce a cleaning fluid; a control system designed to control the temperature of the cleaning fluid; a wafer holder designed to hold and rotate a wafer; a first nozzle above the wafer, which is designed to spray the cleaning fluid onto an upper surface of the wafer; and a second nozzle under the wafer, which is designed to spray the cleaning fluid onto a lower surface of the wafer. [17] System according to claim 16, further comprising: a line connecting the first nozzle to the cooling system, wherein the line is configured to supply the cleaning fluid to the first nozzle; and a valve on the line that is set up to control the flow rate of the cleaning fluid. [18] System according to claim 16 or 17, wherein the temperature of the cleaning fluid is in the range of approximately 5 °C to approximately 15 °C. [19] System according to any one of claims 16 to 18, further comprising: a first temperature sensor, which is arranged and configured at the first nozzle, to measure a first temperature of the cleaning fluid supplied to the first nozzle; and a second temperature sensor, which is arranged and configured at the second nozzle, to measure a second temperature of the cleaning fluid supplied to the second nozzle, wherein the difference between the first temperature and the second temperature is between approximately 0 °C and approximately 5 °C. [20] System according to any one of claims 16 to 19, wherein the cooling system comprises: a first line which is designed to contain a coolant, wherein the diameter of the first line is in the range between approximately 5 mm and approximately 10 mm; a second line designed to contain the cleaning fluid; a temperature sensor on the second line, which is configured to measure the temperature of the cleaning fluid flowing out of the second line; and a cooling tank that is set up to contain the first and second lines.

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