Wafer bearing assembly, semiconductor processing device and control method

Abstract

The invention provides a wafer bearing assembly, a semiconductor processing device and a control method, and the wafer bearing assembly comprises a carrying platform which is used for bearing and adsorbing a wafer; the first gas outlet is formed in the carrying table below the wafer and can blow first gas to the bottom surface of the wafer so as to suspend the wafer; and the second air outlets are circumferentially formed in the outer edge of the wafer and can blow out second air, and the second air extrudes the side wall of the suspended wafer through airflow pressure of the second air so that the wafer can be centered. According to the invention, the side wall of the suspended wafer is extruded by controlling the air pressure of the first gas and the second gas, so that the wafer is centered in a suspended state and is adsorbed and fixed in the center by the carrying table, secondary offset caused by vibration generated when the wafer is driven by the lifting ejector pin to descend is eliminated, and the uniformity of wafer etching is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor equipment, in particular to a wafer bearing assembly, a semiconductor processing device and a control method. BACKGROUND

[0002] With the rapid development of the semiconductor industry, the requirements for etching precision and uniformity of semiconductor processing equipment are increasingly stringent. Among many semiconductor processing equipment, plasma etching devices play a crucial role. Plasma etching devices use high-energy plasma to locally remove specific materials, which is a key process for achieving high-precision and high-selectivity patterning. However, existing plasma etching devices have some technical challenges in processing wafers, especially in terms of wafer centering accuracy.

[0003] In the prior art, the Auto Wafer Center system is one of the mainstream technologies used in plasma etching devices. It sets multiple optical sensors in the transfer module, uses the optical sensors to capture the boundary coordinates of the wafer, and calculates the offset between the current wafer center and the stage center. When the vacuum manipulator transports the wafer into the etching reaction chamber, the offset is compensated into the displacement coordinates of the wafer, and the centering compensation of the wafer is completed. However, in actual etching process, it is found that although the vacuum manipulator sends the wafer into the reaction chamber with the corrected displacement coordinates, the offset of the wafer captured by the optical sensor relative to the stage center still has a large range of fluctuation when the wafer is taken out after etching. For wafers with large offset, the etching rate of the wafer edge position will be affected, thereby affecting the etching uniformity. The traditional mechanical guide structure causes the final centering effect to be less than expected due to the subtle vibration of the wafer touching the guide structure and the subtle structure vibration during the guiding process. SUMMARY

[0004] The purpose of the present application is to provide a wafer bearing assembly, a semiconductor processing device and a control method. By setting a first gas outlet on the stage towards the wafer bottom surface, the wafer is suspended after the first gas outlet blows out the first gas, and then the second gas blown out by the second gas outlet located at the outer edge of the wafer makes the wafer edge be squeezed by the airflow to realize the centering of the wafer, thereby improving the uniformity of wafer etching.

[0005] To achieve the above object, the first aspect of the present application provides a wafer carrying assembly, comprising: a carrier for carrying a wafer; a first gas outlet arranged on the carrier below the wafer, capable of blowing a first gas to the bottom surface of the wafer to make the wafer float; and a second gas outlet arranged circumferentially on the outer edge of the wafer, capable of blowing a second gas to press the sidewall of the floating wafer through the gas flow pressure, so as to center the wafer.

[0006] Optionally, the second gas outlet is arranged on the carrier.

[0007] Optionally, the wafer carrying assembly further comprises a ring arranged around the carrier, and the second gas outlet is arranged on the ring.

[0008] Optionally, the second gas outlets are uniformly distributed circumferentially.

[0009] Optionally, the inner side of the ring has a ring-shaped inclined surface with a decreasing inner diameter from top to bottom, and the second gas outlet is arranged on the ring-shaped inclined surface; and the inner diameter of the ring above the wafer is greater than the outer diameter of the wafer.

[0010] Optionally, the height of the second gas outlet is higher than the height of the first gas outlet.

[0011] Optionally, the gas outlet direction of the second gas outlet has a centripetal component.

[0012] Optionally, the wafer carrying assembly further comprises a ring support for supporting the ring, the ring support has a first through hole, and the ring has a second through hole, the first through hole supplies gas to the second gas outlet through the second through hole, and the diameter of the first through hole is greater than the diameter of the second through hole.

[0013] Optionally, the pressure of the first gas ranges from 10 to 30 Torr, and the pressure of the second gas ranges from 1 to 10 Torr.

[0014] Optionally, the height of the second gas outlet on the ring is not higher than 1 / 3 of the thickness of the ring.

[0015] Optionally, the shape of the second gas outlet is one or more of a hole, a groove or a grid.

[0016] Optionally, a sealing member is arranged circumferentially at the connection between the first through hole and the second through hole to seal the connection.

[0017] Optionally, at least part of the second gas outlet is not covered by the wafer.

[0018] Optionally, the distance from the second gas outlet to the outer edge of the wafer ranges from 0.6mm to 0.8mm.

[0019] The second aspect of the present application provides a semiconductor processing device, comprising: a reaction cavity; the reaction cavity has the wafer carrying assembly of any one of the above aspects, for carrying a wafer; a transmission port through which the wafer is transmitted; the first gas outlet blows a first gas to suspend the wafer after the wafer is transmitted in, and reduces the amount of the first gas after the wafer is centered by the second gas outlet blowing a second gas circumferentially, so that the wafer is centered and adsorbed on the carrier; and / or, the first gas outlet blows a first gas to suspend the wafer before the wafer is transmitted out, and the wafer is centered and taken out by a robot after the second gas outlet blows a second gas circumferentially.

[0020] The third aspect of the present application provides a control method of the wafer carrying assembly of any one of the above aspects, and the carrier further comprises a lifting pin for lifting the wafer, which comprises the following steps:

[0021] S1, lifting the lifting pin to carry the wafer to the lifting pin;

[0022] S2, recovering the lifting pin to lower the wafer, and the first gas outlet blows a first gas to the bottom surface of the wafer, so that the wafer is in a suspended state when the lifting pin is recovered to the inside of the carrier;

[0023] S3, the second gas outlet blows a second gas at a first flow rate, so that the wafer in a suspended state is centered by the action of the second gas on the edge of the wafer;

[0024] S4, reducing the supply of the first gas, so that the wafer is maintained in a centered state and falls onto the carrier to be adsorbed.

[0025] Optionally, the control method of the wafer carrying assembly further comprises: S5, during the process, closing the second gas outlet, or maintaining the second gas to be continuously supplied at a second flow rate, which is less than the first flow rate.

[0026] Optionally, the suspended height of the wafer ranges from 0.2mm to 1mm.

[0027] Optionally, the first gas and the second gas are respectively composed of one or more of helium, nitrogen and argon.

[0028] Compared with the prior art, the technical scheme of the present application has at least the following advantages: a first gas outlet is arranged below the carrier, and a first gas is blown out from the first gas outlet to suspend the wafer; then a second gas outlet is arranged around the outer edge of the wafer, and a second gas is blown out from the second gas outlet to press the sidewall of the suspended wafer by the gas pressure of the second gas, so that the wafer is centered. By controlling the gas pressure (or flow rate) of the first gas and the second gas to press the sidewall of the suspended wafer, the wafer is centered in the suspended state and is fixed at the center of the carrier by adsorption, the secondary deviation caused by the vibration when the lifting pin drives the wafer to be lowered is eliminated, the wafer is located at the center of the carrier when the wafer is adsorbed by the carrier, and the edge etching uniformity of the wafer is improved. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 FIG. 1 is a cross-sectional view of a wafer carrying assembly according to a first embodiment of the present application;

[0030] Figure 2 FIG. 2 is a top view of the wafer carrying assembly according to the first embodiment of the present application; wherein, Figure 2 (a) the wafer is in a deviation state, Figure 2 (b) the wafer is in a centered state;

[0031] Figure 3 FIG. 3 is a cross-sectional view of a wafer carrying assembly according to a second embodiment of the present application;

[0032] Figure 4 FIG. 4 is a cross-sectional view of another wafer carrying assembly according to the second embodiment of the present application;

[0033] Figure 5 FIG. 5 is a top view of another wafer carrying assembly according to the second embodiment of the present application;

[0034] Figure 6 FIG. 6 is a partial enlarged view of another wafer carrying assembly according to the second embodiment of the present application;

[0035] Figure 7 FIG. 7 is a partial enlarged view of a variant of another wafer carrying assembly according to the second embodiment of the present application;

[0036] Figure 8 FIG. 8 is a partial enlarged view of another wafer carrying assembly according to the second embodiment of the present application;

[0037] Figure 9 FIG. 9 is a cross-sectional view of a semiconductor processing device according to the present application;

[0038] Figure 10 FIG. 10 is a flowchart of a control method of a wafer carrying assembly according to the present application. DETAILED DESCRIPTION

[0039] The following will be combined with the appendix in the embodiments of the present invention. Figure 1 ~Attached Figure 10 The technical solutions, structural features, objectives and effects achieved in the embodiments of the present invention will be described in detail.

[0040] It should be noted that the accompanying drawings are in a very simplified form and use non-precise proportions. They are only used to facilitate and clarify the purpose of illustrating the embodiments of the present invention, and are not intended to limit the implementation conditions of the present invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportional relationship, or adjustments to the size should still fall within the scope of the technical content disclosed in the present invention, provided that they do not affect the effects and objectives that the present invention can produce.

[0041] It should be noted that, in this invention, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only the expressly listed elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0042] In existing technologies, an automated wafer centering system compensates for the offset between the wafer center and the stage center to the wafer displacement coordinates to achieve wafer-stage alignment. However, in actual etching processes, it has been found that although the wafer is transported into the etching cavity with the corrected displacement coordinates, the wafer offset captured by the automated wafer centering system still exhibits fluctuations within a 200-micrometer range when the wafer is removed after etching. This problem arises because, during the unloading process of the wafer by the rising and falling pins within the stage, the vibration of the pins themselves and the differences in the descent rates between the pins cause secondary wafer offset. Furthermore, as the critical dimensions of wafers continue to shrink, the uniformity requirements of the etching process become increasingly stringent, and the control precision of the automated wafer centering system cannot meet these process requirements. For wafers with large offsets, the etching rate at the wafer edges is significantly affected, thus impacting etching uniformity.

[0043] To address the aforementioned shortcomings, the present invention employs a method of providing a first gas outlet on the stage below the wafer to suspend the wafer and reduce friction between the wafer and the stage. Simultaneously, a second gas outlet is provided circumferentially on the outer edge of the wafer to blow out a second gas. The air pressure of the second gas compresses the sidewall of the suspended wafer, causing horizontal displacement of the wafer and aligning the center of the wafer with the center of the stage.

[0044] <First Embodiment>

[0045] Based on the above-described inventive concept, the first embodiment of the present invention provides a wafer carrier assembly 100, such as... Figure 1 As shown, the wafer carrier assembly 100 includes: a stage 101 for carrying and adsorbing a wafer W; a first air outlet 102 disposed on the stage 101 below the wafer W, the first air outlet 102 facing the bottom surface of the wafer W, which can blow a first gas onto the bottom surface of the wafer W to suspend the wafer W, i.e., the wafer W does not contact the upper surface of the stage 101 or the friction is minimal; and a second air outlet 103 located on the stage 101 and disposed along the circumference of the stage 101 at the outer edge of the wafer W, which can blow out a second gas, the second gas compressing the sidewall of the suspended wafer W through its airflow pressure, so that the center of the wafer W is aligned with the center of the stage 101.

[0046] To ensure the centering effect of wafer W, such as Figure 2 As shown in (b), the second air outlet 103 is uniformly distributed along the circumference of the stage 101. When the wafer W moves from the offset position to the center position, since the second air outlet 103 is uniformly distributed along the circumference of the stage 101, the air pressure of the second gas blown out by the second air outlet 103 on the outer edge of the wafer W is equal, that is, the compressive force of the second gas on the outer edge of the wafer W is equal. This allows the wafer W to maintain a centered alignment with the stage 101, ensuring the uniformity of the wafer edge during the etching process.

[0047] In this embodiment, as Figure 1As shown, the stage 101 is provided with a first gas guiding channel 111 and a second gas guiding channel 112. The first gas guiding channel 111 and the second gas guiding channel 112 are independent of each other and are not connected. Specifically, the input end of the first gas guiding channel 111 is connected to a first gas source 104, and the output end is connected to each of the first gas outlets 102, for supplying a first gas to the bottom surface of the wafer W to suspend the wafer W. The input end of the second gas guiding channel 112 is connected to a second gas source 105, and the output end is connected to each of the second gas outlets 103, for supplying a second gas to the outer edge of the wafer W. The second air outlet 103 has a centripetal component in its air outlet direction. This is achieved by setting a certain inclined angle between the second air guide channel 112 and the second air outlet 103 relative to the vertical direction, so that the flow direction of the second gas blown out from the second air outlet 103 has a centripetal component. This provides a horizontal centripetal force to squeeze the outer edge of the wafer W, thereby moving the offset wafer W towards the center of the stage 101 and achieving alignment between the wafer W and the stage 101.

[0048] Furthermore, such as Figure 1 As shown, if the second gas channel 112 is vertically arranged, the second gas blown out from the second gas outlet 103 moves in the vertical direction. When the center O' of the wafer W suspended above the stage 101 is offset relative to the center O of the stage 101, as shown... Figure 2 As shown in (a), the distance from the outer edge of the wafer W to each of the second gas outlets 103 is inconsistent. At this time, the second gas flow velocity is high and the dynamic pressure provided by the second gas is high at locations where the distance from the outer edge of the wafer W to the second gas outlet 103a is small; while the second gas flow velocity is low and the dynamic pressure provided by the second gas is low at locations where the distance from the outer edge of the wafer W to the second gas outlet 103b is large. Under the influence of the gas flow pressure, the center O' of the wafer W will gradually approach the center O of the stage 101, thereby achieving alignment between the wafer W and the stage 101 (e.g., ...). Figure 2 (b) It should be noted that, in all embodiments of the present invention, the distance from the outer edge of the wafer W to the second vent 103 refers to the horizontal distance extending radially along the wafer W.

[0049] Furthermore, such as Figure 2As shown in (a), when the wafer W shifts on the stage, the second vent 103 includes a second vent 103c that is at least partially uncovered by the wafer W. The portion of the second vent 103c near the center of the stage 101 is covered by the wafer W, while the portion away from the center of the stage 101 is not covered by the wafer W. This allows the second vent 103c to provide the second gas with a centripetal component or capable of generating dynamic pressure. The airflow pressure of the second gas blown out through the second vent 103c causes the wafer W to move towards the center of the stage 101, achieving alignment between the wafer W and the stage 101. Optionally, the shape of the second vent 103 can be one or more of a hole, a slot, or a grid. The shape of the second vent 103 can be selected according to actual conditions, and this embodiment does not limit this.

[0050] As an optional embodiment, the pressure range of the first gas is 10 to 30 Torr. Within this pressure range, the first gas is sufficient to lift the wafer W, keeping it in a suspended state, without causing the wafer W to flip or undergo secondary displacement due to excessive pressure. Simultaneously, the pressure range of the second gas is 1 to 10 Torr. Since the wafer W is in a suspended state, within this pressure range, the second gas can provide sufficient centripetal force to cause horizontal displacement of the wafer W, moving the offset wafer W towards the center of the stage 101, without causing excessive movement of the wafer W due to excessive gas pressure, thus ensuring more precise alignment between the wafer W and the stage.

[0051] Furthermore, in order to ensure that the extrusion force provided by the second gas blown out of the second outlet 103 can better act on the outer edge of the wafer W, the radial distance from the second outlet 103 to the outer edge of the wafer is in the range of 0.6 to 0.8 mm. Within this radial distance range, the second gas can more effectively provide the extrusion force (including the centripetal force in the horizontal direction of the second gas itself and / or the dynamic pressure generated by the gas flow rate of the second gas) to satisfy the movement of the wafer W towards the center of the stage 101, which is beneficial to enable the wafer W to achieve alignment with the stage 101.

[0052] <Second Embodiment>

[0053] Since the parameters and functions of this embodiment are basically the same as those of the first embodiment described above, the repeated parameters and functions are omitted from the description. Compared with the first embodiment, the main improvement of this embodiment is the position of the second air outlet. The different structures and functions are described below.

[0054] A second embodiment of the present invention provides a wafer carrier assembly 200, such as Figure 3As shown, the edge of the stage 201 in the wafer carrier assembly 200 has an annular step 213. A ring member 204 is provided above the annular step 213 and surrounds the stage 201. In this embodiment, the ring member 204 is disposed on the annular step 213. The second air outlet 203 is located on the ring member 204 and is disposed along the circumference of the ring member 204 at the outer edge of the wafer W. A second gas is blown out through the second air outlet 203. The second gas compresses the sidewall of the suspended wafer W through its airflow pressure, causing the center of the wafer W to move toward the center of the ring member 204. Since the ring member 204 is concentric with the stage 201 by a special tool, by aligning the center of the wafer W with the center of the ring member 204, the center of the wafer W, the center of the ring member 204, and the center of the stage 201 can be aligned. Similar to the first embodiment, the first air outlet 202 is connected to the first air source 204 through the first air guide channel 211 to provide the first gas to the bottom surface of the wafer W, thereby suspending the wafer W. In this embodiment, by setting the second air outlet 203 on the ring 204, the number of openings on the stage 201 is reduced, providing redundant accommodating space for other components (such as lifting pins) assembled within the stage 201.

[0055] Furthermore, such as Figure 4 As shown, Figure 4 Another wafer carrier assembly 200 provided in the second embodiment of the present invention has an annular inclined surface 241 with an inner diameter decreasing from top to bottom on the radially inner side of the ring 204 in the wafer carrier assembly 200, and the second air outlet 203 is located on the annular inclined surface 241. During the process of placing the wafer W in the wafer carrier assembly 200, if the outer edge of the wafer W contacts the inner wall of the ring 204, since the inner wall of the ring 204 is configured as the annular inclined surface 241, it can provide a horizontal component force to the wafer W. As the wafer W slides down along the annular inclined surface 241, the center of the wafer W moves horizontally towards the center of the stage 201, thereby achieving preliminary alignment of the wafer W. Simultaneously, when the first gas is blown to the bottom surface of wafer W, it can flow horizontally along the bottom surface of wafer W towards its outer edge. Due to the obstruction of the annular inclined surface 241 of the ring member 204, a gas barrier is formed between the outer edge of wafer W and the annular inclined surface 241. This gas barrier provides a certain compressive force to the outer edge of wafer W and provides a certain support force to maintain the stability of wafer W in the horizontal direction. It should be noted that the inner diameter of the ring member 204 above wafer W is larger than the outer diameter of wafer W. Figure 5 From the top view, the inner diameter edge of the ring 204 located above the wafer W does not cover the outer edge of the wafer W, that is, the part of the ring 204 located above the wafer W does not restrict the wafer W in the vertical direction.

[0056] Because wafer W is in a suspended state during the alignment process, such as Figure 4 As shown, the second air outlet 203 is at a higher height than the first air outlet 202, so that the second air outlet 203 can be aligned with the sidewall of the suspended wafer W, and the second gas blown out from the second air outlet 203 can act more directly on the sidewall of the wafer W, thereby improving the alignment efficiency of the wafer W.

[0057] Furthermore, in some specific embodiments, the ring 204 is a focusing ring in a plasma processing device. The top of the focusing ring is consumed by the plasma impact in the reaction chamber, resulting in a thinning of the focusing ring. To prevent the formation of a leak in the ring 204 after its thickness decreases, which would allow the second gas to leak into the reaction chamber and cause uneven gas distribution within the reaction chamber, as an optional embodiment, the height of the second outlet 203 on the ring 204 is no higher than 1 / 3 of the thickness of the ring 204. That is, a certain amount of redundant ring thickness is provided above the second outlet 203, which can effectively prevent the formation of a leak in the ring 204, thereby ensuring the stability of the second gas blown out from the second outlet 203.

[0058] like Figure 4 As shown, the wafer carrier assembly 200 further includes a ring support 205, which is disposed on the annular step 213 of the stage 201. The ring 204 is disposed on the ring support 205, and the ring support 205 supports the ring 204. The ring support 205 has a first through hole 251, and the ring 204 has a second through hole 242. The first through hole 251 and the second through hole 242 are connected. The first through hole 251 supplies gas to the second gas outlet 203 through the second through hole 242. The diameter of the first through hole 251 is larger than the diameter of the second through hole 242 to prevent the first through hole 251 and the second through hole 242 from being misaligned due to insufficient assembly precision when the ring 204 is placed on the ring support 205, thus blocking the connection between the first through hole 251 and the second through hole 242 and causing an interruption in the second gas supply. Optionally, the diameter of the first through hole 251 is set to be larger than the diameter of the second through hole 242. By setting the diameter of the first through hole 251 to be larger than the diameter of the second through hole 242, the requirements for assembly accuracy are reduced, thereby improving assembly efficiency.

[0059] Among them, such as Figure 4As shown, the second through-hole 251 is connected to the second gas source 205 through the second gas guide channel 212 to provide the second gas. The second gas is sequentially transmitted through the second gas guide channel 212, the second through-hole 251, and the first through-hole 242 to the second gas outlet 203, and blown from the second gas outlet 203 towards the sidewall of the wafer W. Furthermore, to ensure the sealing of the second gas delivery, a sealing element 206 is circumferentially provided at the connection between the first through-hole 251 and the second through-hole 242. The sealing element 206 is in close contact with the ring element 204 and the ring element support 205 respectively to achieve a sealed connection. By providing the sealing element 206, the flow of the second gas between the ring element 204 and the ring element support 205 can be effectively prevented.

[0060] Specifically, such as Figure 4 and Figure 6 As shown, in this embodiment, the second through hole 242 has an inclined angle relative to the vertical direction toward the wafer W, so that the gas outlet direction of the second through hole 242 has a centripetal component, thereby making the second gas blown out from the second through hole 242 and the second gas outlet 203 have a centripetal component, thereby providing a horizontal centripetal force to squeeze the outer edge of the wafer W, and realizing the alignment of the wafer W with the stage 101.

[0061] Furthermore, such as Figure 7 As shown, when the second through hole 242 is arranged along the vertical direction of the ring 204, the first end of the second through hole 242 (i.e., the port located on the lower surface of the ring 204) is connected to the first through hole 251, and the second end is connected to the second gas outlet 203, for conveying the second gas vertically upward. Due to the inconsistent distances from the outer edge of the offset wafer W to each of the second gas outlets 203 on the ring 204, the second gas flow velocity is high and the dynamic pressure provided by the second gas is high at the location where the distance from the outer edge of the wafer W to the second gas outlet 203 is small; while the second gas flow velocity is low and the dynamic pressure provided by the second gas is low at the location where the distance from the outer edge of the wafer W to the second gas outlet 203 is large. Under the action of the air pressure of the second gas flow, the center of the wafer W will gradually approach the center of the ring 204, thereby achieving the alignment of the wafer W and the ring 204, and thus achieving the alignment of the wafer W and the stage 201.

[0062] Furthermore, such as Figure 8As shown, in another embodiment, the second through hole 242 located within the ring 204 includes a vertically arranged first sub-hole 2421 and a horizontally arranged second sub-hole 2422. The bottom end of the first sub-hole 2421 is connected to the first through hole 251, and the top end is connected to the first end of the second sub-hole 2422. The second end of the second sub-hole 2422 communicates with the second gas outlet 203 for transmitting the second gas. The second sub-hole 2422 and the first sub-hole 2421 have an included angle, ranging from 0° to 180°. When the included angle is not 0° or 180°, the gas outlet direction of the second gas outlet 203 has a centripetal component. That is, when the second gas is blown out of the second gas outlet 203 along the second sub-hole 2422, the second gas can provide a centripetal component of compressive force, thereby enabling the center of the wafer W to move towards the center of the ring 204. In this embodiment, the angle between the second sub-hole 2422 and the first sub-hole 2421 is 90 degrees, that is, the second sub-hole 2422 is set horizontally, so that the second gas output from the second sub-hole 2422 is blown out in the horizontal direction, providing horizontal extrusion force on the sidewall of the wafer W, causing the center of the wafer W to move towards the center of the ring 204.

[0063] Accordingly, the present invention also provides a semiconductor processing apparatus, please refer to... Figure 9 , Figure 9 This is a cross-sectional schematic diagram of a semiconductor processing apparatus provided in an embodiment of the present invention. The semiconductor processing apparatus includes a reaction chamber 300, which includes a generally cylindrical reaction chamber sidewall 301 made of a metallic material. A wafer carrier assembly as described in any of the above embodiments is provided within the reaction chamber 300 for carrying a wafer W. A transfer port 311 is formed on the reaction chamber sidewall 301, through which the wafer W is transferred. Specifically, taking the wafer carrier assembly 100 in the first embodiment as an example, after the wafer W is introduced, the first gas outlet 102 blows a first gas to suspend the wafer W, and then a second gas is blown circumferentially through the second gas outlet 103 to center the wafer W and reduce the amount of the first gas, so that the wafer W is centrally adsorbed on the stage 101.

[0064] Furthermore, a gas supply assembly 302 is provided at the top of the reaction chamber 300. The gas supply assembly 302 is arranged opposite to the wafer carrier assembly and is used to introduce reaction gas into the reaction chamber 300 to perform etching or thin film deposition processes on the wafer W located on the stage 101. When the wafer W completes the process and is about to be transferred out of the reaction chamber 300, the first gas outlet 102 blows out a first gas to suspend the wafer W, and a second gas is blown out circumferentially through the second gas outlet 103 to center it. After the wafer W is centered, it is picked up from the transfer port 311 by the robotic fork and transferred out.

[0065] likeFigure 10 As shown, the present invention also provides a control method for a wafer carrier assembly provided in the first or second embodiment. Figure 9 Taking a semiconductor processing device as an example, the stage 101 is further provided with a rising pin 104. The rising pin 104 is located in the stage 101 below the wafer W. The rising pin 104 is connected to a driving device (not shown in the figure) to drive the rising pin 104 to rise or fall. When the rising pin 104 extends out of the stage 101, the top of the rising pin 104 contacts the bottom surface of the wafer W. The control method includes:

[0066] Step S1: Raise the lifting pin 104 and transfer the wafer W to the lifting pin 104; specifically, the driving device drives the lifting pin 104 to rise to the loading position, opens the transfer port 311, and the mechanical fork transfers the wafer W from the transfer port 311 to the reaction chamber 300 and places the wafer W on the lifting pin 104.

[0067] Step S2: Retract the lifting pin 104, causing the wafer W to descend. The first air outlet 102 blows a first gas onto the bottom surface of the wafer W, so that the wafer W is in a suspended state when the lifting pin 104 is retracted into the stage 101. Specifically, the driving device drives the lifting pin 104 to descend, causing the wafer W to descend vertically. Simultaneously with the descent of the wafer W, the first air source 104 delivers the first gas through the first air guide channel 111. The first gas is blown from the first air outlet 102 onto the bottom surface of the wafer W. When the lifting pin 104 is retracted into the stage 101, the wafer W is in a suspended state due to the buoyancy provided by the first gas. Preferably, the suspension height of the wafer W is in the range of 0.2–1 mm to eliminate friction between the wafer W and the stage 101.

[0068] Step S3: The second gas outlet 103 blows out the second gas at a first flow rate, causing the edge of the suspended wafer W to be centered by the action of the second gas. Specifically, the second gas source 105 delivers the second gas at a first flow rate through the second gas guide channel 112. The second gas is blown out from the second gas outlet 103. Since the wafer W is in a suspended state, after being subjected to the air pressure of the second gas flow, the center of the wafer W moves towards the center of the stage 101, thereby achieving the centering of the wafer W. Optionally, the first gas and the second gas are composed of one or more of helium, nitrogen, and argon.

[0069] Step S4: Reduce the supply of the first gas to allow the wafer W to remain centered as it falls onto the stage 101 and is adsorbed and fixed. Specifically, once the wafer W is centered, reduce the flow rate of the first gas to allow the wafer W to gradually descend from its suspension height until it is adsorbed and fixed by the electrostatic adsorption force provided by the stage 101.

[0070] Furthermore, such as Figure 10 As shown, the control method further includes: step S5, closing the second gas outlet 103 during the process; in other embodiments, during the process, the second gas can be continuously supplied at a second flow rate to avoid deposits forming at the second gas outlet 103 and blocking it. The second flow rate is less than the first flow rate to prevent excessive flow of the second gas from affecting the gas distribution on the wafer W surface during the process, thereby reducing the uniformity of etching on the wafer W surface.

[0071] In summary, the wafer carrier assembly, semiconductor processing apparatus, and control method provided by this invention suspend the wafer W by setting a first air outlet 102 on a stage 101 below the bottom surface of the wafer W and blowing a first gas from the first air outlet 102; then, by setting a second air outlet 103 circumferentially on the outer edge of the wafer W and blowing a second gas from the second air outlet 103, the air pressure of the second gas compresses the sidewalls of the suspended wafer W, thus centering the wafer W. By controlling the air pressure (or flow rate) of the first and second gases to compress the sidewalls of the suspended wafer W, the wafer W is centered in the suspended state and is adsorbed and fixed in the center by the stage 101, eliminating the secondary displacement caused by the vibration generated when the lifting pin 104 lowers the wafer W, ensuring that the wafer is located in the center of the stage 101 when adsorbed by the stage 101, and improving the edge etching uniformity of the wafer W. Compared to mechanical structure-guided alignment methods that involve contact or semi-contact, this alignment process relies entirely on air pressure rather than being limited by mechanical structure boundaries. Air pressure regulation does not cause vibration or displacement due to mechanical contact, making the alignment process more stable and controllable. It is not limited by mechanical structure boundaries, can adapt to alignment of various wafer sizes, is not sensitive to minor differences in wafer size, and has higher alignment stability and controllability.

[0072] It is easy to understand that "alignment" in this invention means the alignment of the wafer center with the stage center, which can be understood as "centering" or "aligning with the center".

[0073] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A wafer carrier component, characterized in that, include: Stage, the stage being used to support the adsorbed wafer; The first air outlet is located on the platform below the wafer and can blow a first gas onto the bottom surface of the wafer to suspend the wafer. The second air outlet is circumferentially located at the outer edge of the wafer and can blow out a second gas. The second gas, through its airflow pressure, compresses the sidewall of the suspended wafer, thereby centering the wafer.

2. The wafer carrier assembly as described in claim 1, characterized in that, The second air outlet is located on the platform.

3. The wafer carrier assembly as described in claim 1, characterized in that, Also includes: A ring is arranged around the platform; the second air outlet is located on the ring.

4. The wafer carrier assembly as described in claim 1, characterized in that, The second air outlet is evenly distributed circumferentially.

5. The wafer carrier assembly as described in claim 3, characterized in that, The ring has an annular inclined surface on its radially inner side, with the inner diameter decreasing from top to bottom, and the second air outlet is located on the annular inclined surface; Furthermore, the inner diameter of the ring located above the wafer is larger than the outer diameter of the wafer.

6. The wafer carrier assembly as described in claim 3, characterized in that, The second air outlet is located at a higher height than the first air outlet.

7. The wafer carrier assembly as described in claim 1, characterized in that, The air outlet of the second outlet has a centripetal component in its air outlet direction.

8. The wafer carrier assembly as described in claim 3, characterized in that, It also includes a ring support member that supports the ring member. The ring support member has a first through hole and the ring member has a second through hole. The first through hole supplies air to the second air outlet through the second through hole. The diameter of the first through hole is larger than the diameter of the second through hole.

9. The wafer carrier assembly as described in claim 1, characterized in that, The pressure range of the first gas is 10 to 30 Torr, and the pressure range of the second gas is 1 to 10 Torr.

10. The wafer carrier assembly as described in claim 3, characterized in that, The height of the second air outlet on the ring is no higher than 1 / 3 of the thickness of the ring.

11. The wafer carrier assembly as claimed in claim 1, characterized in that, The shape of the second air outlet is one or more of the following: hole, groove, or grid.

12. The wafer carrier assembly as described in claim 8, characterized in that, A sealing element is provided circumferentially at the connection between the first through hole and the second through hole to seal the connection.

13. The wafer carrier assembly as claimed in claim 1, characterized in that, The second vent is at least partially not covered by the wafer.

14. The wafer carrier assembly as claimed in claim 1, characterized in that, The distance from the second vent to the outer edge of the wafer ranges from 0.6 to 0.8 mm.

15. A semiconductor processing apparatus, characterized in that, include: reaction chamber; The reaction chamber contains a wafer carrier assembly as described in any one of claims 1 to 14, for carrying the wafer; A transmission port through which the wafer is transmitted; After the wafer is introduced, the first gas outlet blows a first gas to suspend the wafer, and then the second gas outlet blows a second gas circumferentially to center the wafer, reducing the amount of the first gas so that the wafer is centrally adsorbed on the carrier; and / or, When the wafer is about to be delivered, the first air outlet blows a first gas to suspend the wafer, and the second air outlet blows a second gas circumferentially to center the wafer, so that the wafer is centered and then picked up and delivered by the robotic arm.

16. A control method for a wafer carrier assembly as described in any one of claims 1 to 14, characterized in that, The stage is also equipped with lifting pins for lifting the wafer, including the following steps: S1. Raise the lifting pin and transfer the wafer onto the lifting pin; S2. Retract the lifting pin to drive the wafer down, and blow the first gas through the first air outlet to the bottom surface of the wafer so that the wafer is in a suspended state when the lifting pin is retracted into the stage. S3. The second outlet blows out the second gas at the first flow rate, so that the edge of the suspended wafer is centered by the action of the second gas. S4. Reduce the supply of the first gas so that the wafer remains in an centered state and falls onto the stage to be adsorbed.

17. The control method as described in claim 16, characterized in that, Also includes: S5. During the process, close the second air outlet, or The second gas is continuously supplied at a second flow rate, which is less than the first flow rate.

18. The control method as described in claim 16, characterized in that, The levitation height of the wafer ranges from 0.2 to 1 mm.

19. The control method as described in claim 16, characterized in that, The first gas and the second gas are each composed of one or more of helium, nitrogen, and argon.

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