Air intake structure and semiconductor device

Abstract

The application discloses an air inlet structure and a semiconductor device, and belongs to the technical field of semiconductor devices, and is used for solving the problem of uneven wafer etching; the air inlet structure comprises a shower head, a first air cavity, a second air cavity and a third air cavity; the shower head comprises a top wall, a side wall and a bottom wall, the shower head is provided with one or more first air outlets, one or more second air outlets and one or more third air outlets, the distances from the third air outlets, the second air outlets and the first air outlets to the central axis of the shower head gradually increase, the central axis of the shower head penetrates one third air outlet, the first air outlet penetrates from the top wall to the side wall, and the second air outlet and the third air outlet penetrate from the top wall to the bottom wall; the first air cavity, the second air cavity and the third air cavity are all connected with the top wall of the shower head, the first air outlet is communicated with the first air cavity, the second air outlet is communicated with the second air cavity, and the third air outlet is communicated with the third air cavity; the air inlet structure provides process gas for the semiconductor device.

Description

Technical Field

[0001] This application relates to the field of semiconductor equipment technology, and more particularly to an air intake structure and a semiconductor device. Background Technology

[0002] In the field of semiconductor equipment technology, there is a need to introduce gases. For example, in plasma etching equipment, process gases need to be introduced into the reaction chamber. The process gases (such as oxygen, fluoride gases, etc.) are excited in an electric field to generate high-energy electrons and ions. These high-energy particles bombard the wafer in the reaction chamber to achieve the etching of the wafer.

[0003] For example, gas can be introduced into the reaction chamber through a nozzle. However, existing nozzle designs are relatively simple, and the gas ejected from the nozzle is unevenly distributed, resulting in uneven wafer etching in semiconductor devices. Summary of the Invention

[0004] This application discloses an air intake structure and a semiconductor device for solving the problem of uneven wafer etching.

[0005] In a first aspect, this application provides an air intake structure for use in a semiconductor device. The air intake structure includes a spray head and a first air chamber, a second air chamber, and a third air chamber that are isolated from each other. The spray head includes a top wall, a side wall, and a bottom wall that are sequentially connected. The spray head is provided with one or more first air outlets, one or more second air outlets, and one or more third air outlets that are isolated from each other. The distances from the third air outlet, the second air outlet, and the first air outlet to the central axis of the spray head increase sequentially, and the central axis of the spray head passes through one of the one or more third air outlets. The first air outlet extends from the top wall to the side wall, and the second and third air outlets extend from the top wall to the bottom wall. The first air chamber, the second air chamber, and the third air chamber are all connected to the top wall of the spray head. The first air outlet communicates with the first air chamber, the second air outlet communicates with the second air chamber, and the third air outlet communicates with the third air chamber.

[0006] Thus, the distances from the third, second, and first vents to the central axis of the spray head increase sequentially. The area where the third vent is located can be called the central region of the spray head, the area where the second vent is located can be called the middle region, and the area where the first vent is located can be called the edge region. In other words, by having vents in the central, middle, and edge regions of the spray head, and with these three types of vents penetrating the bottom and side walls of the spray head, the air intake distribution of the semiconductor device becomes more uniform. Furthermore, because the three types of vents are isolated from each other, and the three air chambers connected to each vent are also isolated from each other, the flow rate or composition of the three vents can be independently and flexibly adjusted, improving the controllability of the airflow and enhancing the etching uniformity of the wafer by the semiconductor device. Moreover, the central axis of the spray head penetrating the third vent effectively overcomes the problem of uneven etching in the central region of the wafer, thereby improving the uniformity of wafer etching.

[0007] In one possible implementation, the air intake structure further includes: a first air supply pipe, a second air supply pipe, and a third air supply pipe, wherein the first air supply pipe is connected to the first air chamber, the second air supply pipe is connected to the second air chamber, and the third air supply pipe is connected to the third air chamber; the first air supply pipe, the second air supply pipe, and the third air supply pipe are all used to input the same mixed gas, and the mass ratio of the gas components in the mixed gas is different in at least two of the first air supply pipe, the second air supply pipe, and the third air supply pipe.

[0008] In this way, by connecting each gas chamber to an independent gas supply pipe, and by allowing different gas supply pipes to input mixed gas with different mass ratios of gas components, the flow rate or composition of the three outlets of the gas intake structure can be flexibly adjusted. The adjustment of the flow rate or composition of the three outlets of the gas intake structure affects the concentration of etching gas at different locations in the etching area, thereby affecting the etching rate of different areas of the wafer. The uniformity of wafer etching can be improved by adjusting the flow rate or composition of the three outlets of the gas intake structure.

[0009] In one possible implementation, the mixed gas is used to etch a wafer in the semiconductor device; the gas inlet structure further includes: a first mass flow controller, a second mass flow controller, and a third mass flow controller, wherein the first mass flow controller is disposed in the first gas supply pipe, the second mass flow controller is disposed in the second gas supply pipe, and the third mass flow controller is disposed in the third gas supply pipe; at least one of the first mass flow controller, the second mass flow controller, and the third mass flow controller adjusts the mass ratio of the gas components of the mixed gas according to the etching amount of the wafer.

[0010] In this way, the mass flow controller can adjust the ratio of each component of the mixed gas in the corresponding gas delivery pipe, making the etching gas more controllable and improving the etching uniformity of the wafer.

[0011] In one possible implementation, adjusting the mass ratio of the gas components in the mixed gas according to the etching amount of the wafer includes: when the mixed gas includes NF3 and NH3, increasing the mass ratio of NF3 in the mixed gas when the actual etching amount of the wafer is less than the target etching amount of the wafer; and when the mixed gas includes Cl2, SF6 and O2, increasing the mass ratio of SF6 in the mixed gas when the actual etching amount of the wafer is less than the target etching amount of the wafer.

[0012] In this way, the flow rate of each gas supply pipe and the mass ratio of each component gas can be adjusted simultaneously, resulting in greater controllability of the etching gas and improved wafer etching uniformity. For example, the ionization of a mixture of NF3 and NH3 produces F ions and F radicals. Under the bias voltage of the semiconductor equipment's reaction chamber, the F ions are used to etch the wafer. In the NF3 and NH3 mixture, the higher the mass proportion of NF3, the more F ions are generated after ionization, which is more beneficial to wafer etching. For example, when the etching amount in the central region of the wafer is relatively small, the mass proportion of NF3 in the mixture of gas at the third outlet can be increased by adjusting the third mass flow controller to increase the amount of F ions generated, thereby increasing the etching amount in the central region of the wafer.

[0013] In one possible implementation, one of the first, second, and third air supply pipes is located on a different side of the spray head, respectively, from the other two of the first, second, and third air supply pipes.

[0014] Thus, considering the spatial arrangement of the pipes around the spray head, the three air inlet pipes can be connected to the corresponding air chambers from different directions, so that the three air supply pipes are not concentrated on the same side of the spray head, avoiding interference between these pipes and making the arrangement of the multiple pipes of the spray head more reasonable.

[0015] In one possible implementation, the number of the third vent is less than the number of the second vent, and the number of the second vent is less than or equal to the number of the first vent.

[0016] Thus, taking the edge, middle, and central regions of the spray head as having roughly the same radial dimensions, the central region of the spray head has a smaller space compared to the edge and middle regions. Therefore, the number of third vents can be reduced. The third vents are closer to the central axis of the spray head, and the radius of the ring containing multiple third vents is smaller than the radius of the ring containing multiple second vents, which in turn is smaller than the radius of the ring containing multiple first vents. By setting the relationship between the number of third, second, and first vents, they can be arranged at approximately the same intervals, resulting in a more uniform overall vent distribution. Similarly, the central region of the wafer has less space and requires less etching gas. Therefore, the number of third vents should be minimized to meet the etching gas requirements of different regions of the wafer.

[0017] In one possible implementation, the number of the third vent is 4n+1, the number of the second vent is 4m, and the number of the first vent is 4q, where n is an integer from 0 to 6, m is an integer from 1 to 7, and q is an integer from 1 to 7.

[0018] By placing one vent at the central axis of the spray head, and arranging the other vents evenly around the central axis, the vents are distributed evenly across the four quadrants, improving the overall uniformity of the vent arrangement. This results in higher uniformity of etching across different areas of the wafer.

[0019] In one possible implementation, the dimensions of the third vent, the second vent, and the first vent are all different.

[0020] In this way, by setting different sizes of the air outlets in different areas of the spray head, the size of the air outlets can be adjusted according to the etching amount of the wafer. When the etching amount in a certain area of ​​the wafer is small, the size of the air outlet corresponding to that area can be increased, thereby realizing the control of the airflow in different areas of the spray head, so that the supply of process gas meets the requirements of wafer etching uniformity.

[0021] In one possible implementation, the size of the third vent is smaller than the size of the second vent, and the size of the second vent is smaller than the size of the first vent.

[0022] Since the central area of ​​the spray head has less space compared to the edge and middle areas, the diameter of the third vent can be smaller. By setting the size relationship of the different types of vents, the etching gas requirements of different areas of the wafer can be met, thereby achieving the purpose of uniform etching of the wafer.

[0023] In one possible implementation, the second air outlet is divided into multiple groups of second air outlets, with each group of second air outlets having an equal distance from the central axis of the spray head, and different groups of second air outlets having different distances from the central axis of the spray head. The second air chamber includes multiple first air distribution chambers isolated from each other, with one group of second air outlets communicating with one of the first air distribution chambers. The air intake structure further includes multiple second air supply pipes, with one second air supply pipe communicating with one of the first air distribution chambers. Alternatively, the first air outlet is divided into multiple groups of first air outlets, with each group of first air outlets having an equal distance from the central axis of the spray head, and different groups of first air outlets having different distances from the central axis of the spray head. The first air chamber includes multiple second air distribution chambers isolated from each other, with one group of first air outlets communicating with one of the second air distribution chambers. The air intake structure further includes multiple first air supply pipes, with one first air supply pipe communicating with one of the second air distribution chambers.

[0024] Thus, at least two independent second air outlets can be provided in the middle area of ​​the spray head, and / or at least two independent first air outlets can be provided in the edge area of ​​the spray head. Each set of second air outlets can be used for independent air intake, and each set of first air outlets can be used for independent air intake, so as to achieve more refined control of the process gas intake flow rate and ratio by zone, resulting in better wafer etching uniformity.

[0025] Secondly, this application provides a semiconductor device that includes an air intake structure as described in any of the above embodiments.

[0026] The beneficial effects of the aforementioned semiconductor device are the same as those of the air intake structure provided in the first aspect of this application, and will not be repeated here. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a structural diagram of a semiconductor device according to an embodiment of this application; Figure 2 This is a perspective view of the air intake structure according to an embodiment of this application; Figure 3 This is a side view of the air intake structure according to an embodiment of this application; Figure 4This is a top view of the air intake structure according to an embodiment of this application; Figure 5 According to Figure 4 A cross-sectional view of the provided air intake structure along section line AA; Figure 6 According to Figure 3 A cross-sectional view of the provided intake structure along section line BB; Figure 7 This is a structural diagram of another air intake structure according to an embodiment of this application; Figure 8 This is a distribution diagram of wafer etching removal amount according to an embodiment of this application; Figure 9 This is a structural diagram of another air intake structure according to an embodiment of this application; Figure 10 According to Figure 3 A cross-sectional view of the provided intake structure along section line CC; Figure 11 According to Figure 3 Another cross-sectional view of the provided intake structure along section line CC; Figure 12 According to Figure 3 Another cross-sectional view of the provided intake structure along section line BB.

[0029] Explanation of reference numerals in the attached figures: 100 - Semiconductor equipment; 10 - Air intake structure; 20 - Equipment body; 30 - Dielectric window; 40 - Support component; 50 - Wafer; 11-Spray head; 12-Air chamber section; 111-Top wall; 112-Side wall; 113-Bottom wall; 121-First air chamber; 122-Second air chamber; 123-Third air chamber; 131-First gas supply pipe; 132-Second gas supply pipe; 133-Third gas supply pipe; 141-First mass flow controller; 142-Second mass flow controller; 143-Third mass flow controller; 201-Reaction chamber; 202-Exhaust port; 1011 - First air outlet; 1012 - Second air outlet; 1013 - Third air outlet; 1221 - First air distribution chamber; 1211 - Second air distribution chamber. Detailed Implementation

[0030] like Figure 1 As shown, an embodiment of this application provides a semiconductor device 100, which includes: an air intake structure 10, a device body 20, a dielectric window 30, and a support member 40.

[0031] For example, the device body 20 is configured to form a reaction chamber 201, and the top of the device body 20 has an opening communicating with the reaction chamber 201. A dielectric window 30 is disposed on the device body 20 and covers the opening. The device body 20 is also provided with an exhaust port 202 for venting gas from the reaction chamber 201.

[0032] For example, a coil is also provided on the top of the semiconductor device 100. For instance, the coil is located on the top of the dielectric window 30 and connected to the radio frequency matching device. After the radio frequency is connected, an alternating magnetic field is generated to excite the process gas in the reaction chamber 201 to generate a high concentration of plasma for related etching and other processes.

[0033] For example, the dielectric window 30 is an insulating dielectric window used to cover the opening of the reaction chamber 201 and ensure that the electromagnetic field generated by the coil penetrates into the reaction chamber 201. The dielectric window 30 can improve the transmission efficiency of the coil magnetic field into the reaction chamber 201 and ensure the vacuum environment of the reaction chamber 201.

[0034] For example, a dielectric window temperature control device is provided on the dielectric window 30. The dielectric window temperature control device provides high temperature to the dielectric window 30 for heating the dielectric window 30, so that the temperature of the dielectric window 30 is controlled within the normal operating range.

[0035] For example, the gas inlet structure 10 passes through the dielectric window 30 to input process gas into the reaction chamber 201. The support member 40 is located inside the reaction chamber 201 and is used to support the wafer 50 and enable the wafer 50 to reach a suitable process temperature, such as 30°C. The plasma generated by the process gas is used for etching the wafer 50. That is, the semiconductor device 100 can be used to etch the wafer 50.

[0036] In some examples, such as Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, Figure 2 This is a perspective view of the air intake structure 10 according to an embodiment of this application. Figure 3 This is a side view of the air intake structure 10 according to an embodiment of this application. Figure 4 This is a top view of the air intake structure 10 according to an embodiment of this application. Figure 5 According to Figure 4The provided air intake structure 10 is shown in a cross-sectional view along section line AA. The air intake structure 10 includes: a spray head 11, and a first air chamber 121, a second air chamber 122, and a third air chamber 123 that are isolated from each other. The spray head 11 includes: a top wall 111, a side wall 112, and a bottom wall 113 that are connected in sequence. The spray head 11 is provided with one or more first air outlets 1011, one or more second air outlets 1012, and one or more third air outlets 1013 that are isolated from each other. The distance from the third air outlet 1013, the second air outlet 1012, and the first air outlet 1011 to the central axis L1 of the spray head 11 is... The distance increases sequentially, and the central axis L1 of the spray head 11 passes through one of the three third air outlets 1013. The first air outlet 1011 extends from the top wall 111 to the side wall 112, and the second air outlet 1012 and the third air outlet 1013 extend from the top wall 111 to the bottom wall 113. The first air chamber 121, the second air chamber 122 and the third air chamber 123 are all connected to the top wall 111 of the spray head 11. The first air outlet 1011 communicates with the first air chamber 121, the second air outlet 1012 communicates with the second air chamber 122, and the third air outlet 1013 communicates with the third air chamber 123.

[0037] For example, the air intake structure 10 includes an air chamber 12, which has a first air chamber 121, a second air chamber 122, and a third air chamber 123 spaced apart. The spray head 11 is made of ceramic. The air chamber 12 and the spray head 11 are mated and connected, so that the first air outlet 1011 communicates with the first air chamber 121, the second air outlet 1012 communicates with the second air chamber 122, and the third air outlet 1013 communicates with the third air chamber 123. A rubber ring can be provided at the mating point between the air chamber 12 and the spray head 11 to prevent air leakage between adjacent air chambers.

[0038] For example, such as Figure 6 As shown, Figure 6 According to Figure 3 The provided air intake structure 10 has a cross-sectional view along the section line BB. The first air chamber 121 is a cylindrical cavity, the second air chamber 122 is an annular cavity, and the third air chamber 123 is an annular cavity. The third air chamber 123 is located on the side of the second air chamber 122 away from the first air chamber 121.

[0039] In the embodiments of this application, the spray head 11 is provided with multiple types of air outlets, and the spray head 11 includes at least three types of air outlets. The three types of air outlets are arranged according to the difference in distance from the central axis L1 of the spray head 11. The air outlets are used to deliver process gas to the etching region in the reaction chamber 201 of the semiconductor device 100. The process gas is ionized to form etching gas, which is used to etch the wafer 50.

[0040] The central axis L1 of the spray head 11 passes through the third vent 1013. The distances from the third vent 1013, the second vent 1012, and the first vent 1011 to the central axis L1 of the spray head 11 increase sequentially. The area where the third vent 1013 is located can be called the central area of ​​the spray head 11, the area where the second vent 1012 is located can be called the middle area of ​​the spray head 11, and the area where the first vent 1011 is located can be called the edge area of ​​the spray head 11. That is, by having vents in the central area, middle area, and edge area of ​​the spray head 11, and by having the three types of vents passing through the bottom wall 113 and side wall 112 of the spray head 11, the air intake distribution of the semiconductor device 100 is relatively uniform.

[0041] For example, in Figure 6 , Figure 10 , Figure 11 and Figure 12 In the diagram, dashed ring h1 is the boundary between the central region and the middle region, and dashed ring h2 is the boundary between the middle region and the edge region. Dashed rings h1 and h2 are merely examples of the boundaries between adjacent regions, and are not restrictions on the boundaries between adjacent regions.

[0042] Corresponding to the central region, intermediate region, and edge region of the spray head 11, different locations of the etching region can be referred to as the central region, intermediate region, and edge region of the etching region. Different types of vents are used to transmit process gas to different locations of the etching region. The third vent 1013 is used to transmit process gas to the central region of the etching region, the second vent 1012 is used to transmit process gas to the intermediate region of the etching region, and the first vent 1011 is used to transmit process gas to the edge region of the etching region.

[0043] For example, the diameter of the wafer 50 can be larger than the diameter of the spray head 11. The reaction gas of the first vent 1011 is used to provide etching gas to the edge region of the wafer 50. Compared with the first vent 1011 extending from the top wall 111 to the bottom wall 113, the first vent 1011 extending from the top wall 111 to the side wall 112 can increase the coverage of the etching gas at the edge of the wafer 50, thereby improving the etching uniformity of the wafer 50. For example, if the diameter of the wafer 50 is 300 mm and the diameter of the spray head 11 is 50 mm, by setting the first vent 1011 to extend from the top wall 111 to the side wall 112, the etching uniformity of the larger diameter wafer 50 can be improved.

[0044] The gas chambers are used to supply process gas to different types of gas outlets. The first gas chamber 121 supplies process gas to the first gas outlet 1011, the second gas chamber 122 supplies process gas to the second gas outlet 1012, and the third gas chamber 123 supplies process gas to the third gas outlet 1013. The process gas first enters the corresponding gas chamber, which has the function of equalizing the gas flow. After the pressure and flow rate of the process gas stabilize in the gas chamber, it enters the corresponding gas outlet.

[0045] Furthermore, since the three types of air holes are isolated from each other, and the three air chambers connected to each type of air hole are also isolated from each other, the flow rate or composition of the three outlet air can be adjusted independently and flexibly, which improves the controllability of the airflow and can improve the etching uniformity of the semiconductor device 100 on the wafer 50.

[0046] In some other examples, such as Figure 7 As shown, and as Figure 5 Compared to the air intake structure 10 shown, the third air outlet 1013 and the third air chamber 123 are not provided. As a result, the second air outlet 1012 does not deliver enough etching gas to the central region, which will lead to poor etching uniformity in the central region of the wafer 50.

[0047] In the air intake structure 10 of the semiconductor device 100, such as Figure 7 In the case shown, the semiconductor device 100 is used to etch the wafer 50. Figure 8 This is a distribution diagram of the etching removal amount of a wafer 50 according to an embodiment of this application. The legend on the right represents the etching removal amount, which gradually increases from bottom to top. The numbers on wafer 50 represent the etching removal amount of wafer 50 in that region. The larger the value in that region of wafer 50, the greater the etching removal amount of wafer 50. From Figure 8 It can be seen that the amount of etching removal in the central region of wafer 50 is less than that in the middle and edge regions.

[0048] Therefore, by setting an air outlet at the central axis L1 position of the spray head 11, the problem of uneven etching in the central area of ​​the semiconductor device 100 corresponding to the wafer 50 can be effectively overcome, thereby improving the uniformity of etching of the wafer 50.

[0049] In some examples, such as Figures 1-5 As shown, the air intake structure 10 further includes: a first air supply pipe 131, a second air supply pipe 132, and a third air supply pipe 133. The first air supply pipe 131 is connected to the first air chamber 121, the second air supply pipe 132 is connected to the second air chamber 122, and the third air supply pipe 133 is connected to the third air chamber 123. The first air supply pipe 131, the second air supply pipe 132, and the third air supply pipe 133 are all used to input the same mixed gas, and the mass ratio of the gas components in the mixed gas is different in at least two of the first air supply pipe 131, the second air supply pipe 132, and the third air supply pipe 133.

[0050] It is understandable that the mixed gas here is the process gas mentioned above.

[0051] For example, the mixed gas includes NF3 and NH3, and NF3 and NH3 are gaseous components that make up the mixed gas. Then, in at least two of the first gas supply pipe 131, the second gas supply pipe 132, and the third gas supply pipe 133, the mass ratio of NF3 and NH3 is different.

[0052] For example, the mixed gas includes Cl2, SF6 and O2, and Cl2, SF6 and O2 are the gas components that make up the mixed gas. Then, in at least two of the first gas supply pipe 131, the second gas supply pipe 132 and the third gas supply pipe 133, the mass ratio of Cl2, SF6 and O2 is different.

[0053] Each gas chamber is connected to an independent gas supply pipe, and different gas supply pipes can input mixed gas with different gas component mass ratios. This achieves the purpose of flexibly adjusting the flow rate or composition of the three outlets of the gas inlet structure 10. The adjustment of the flow rate or composition of the three outlets of the gas inlet structure 10 affects the concentration of etching gas at different positions in the etching area, thereby affecting the etching rate of different areas of the wafer 50. The uniformity of the etching of the wafer 50 is improved by adjusting the flow rate or composition of the three outlets of the gas inlet structure 10.

[0054] In some examples, such as Figures 1-5 As shown, the mixed gas is used to etch the wafer 50 in the semiconductor device 100; the gas inlet structure 10 further includes: a first mass flow controller 141, a second mass flow controller 142, and a third mass flow controller 143, the first mass flow controller 141 being disposed in the first gas supply pipe 131, the second mass flow controller 142 being disposed in the second gas supply pipe 132, and the third mass flow controller 143 being disposed in the third gas supply pipe 133; at least one of the first mass flow controller 141, the second mass flow controller 142, and the third mass flow controller 143 adjusts the mass ratio of the gas components of the mixed gas according to the etching amount of the wafer 50.

[0055] The mass flow controller can adjust the mass ratio of each component of the mixed gas in the corresponding gas delivery pipe. When the mixed gas includes NF3 and NH3, the first mass flow controller 141 can control the mass ratio of NF3 and NH3 entering the first gas outlet 1011, the second mass flow controller 142 can control the mass ratio of NF3 and NH3 entering the second gas outlet 1012, and the third mass flow controller 143 can control the mass ratio of NF3 and NH3 entering the third gas outlet 1013, thereby realizing the separate control of the mass ratio of NF3 and NH3 in the first gas outlet 1011, the second gas outlet 1012, and the third gas outlet 1013.

[0056] For example, adjusting the mass ratio of gas components in the mixed gas according to the etching amount of wafer 50 includes: when the mixed gas includes NF3 and NH3, and when the actual etching amount of wafer 50 is less than the target etching amount of wafer 50, increasing the mass ratio of NF3 in the mixed gas.

[0057] The mixed gas of NF3 and NH3 is ionized to generate F ions and F radicals. Under the bias voltage of the reaction chamber 201 of the semiconductor device 100, the F ions are used to etch the wafer 50. In the mixed gas of NF3 and NH3, the higher the mass proportion of NF3, the more F ions are generated after ionization, the greater the etching rate of the wafer 50, and the greater the actual etching amount of the wafer 50. For example, when the etching amount in the central region of the wafer 50 is small, the mass proportion of NF3 in the mixed gas of the third outlet 1013 is increased by regulating the third mass flow controller 143 to increase the amount of F ions generated, thereby increasing the etching amount in the central region of the wafer 50.

[0058] For example, when the mixed gas includes NF3 and NH3, the intake volumes of the first gas supply pipe 131, the second gas supply pipe 132, and the third gas supply pipe 133 are initially set to be the same, i.e., the intake volumes of the first gas supply pipe 131, the second gas supply pipe 132, and the third gas supply pipe 133 are set to 1:1:1. For instance, if the etching level of wafer 50 is low in the central region of wafer 50, the intake volume of the third gas supply pipe 133 can be increased, or the mass percentage of NF3 in the third gas supply pipe 133 can be increased, or both the intake volume and the mass percentage of NF3 in the third gas supply pipe 133 can be increased simultaneously. If the etching level of wafer 50 is low in the edge region of wafer 50, the intake volume of the first gas supply pipe 131 can be increased, or the mass percentage of NF3 in the first gas supply pipe 131 can be increased, or both the intake volume and the mass percentage of NF3 in the first gas supply pipe 131 can be increased simultaneously.

[0059] For example, when the mixed gas includes NF3 and NH3, the intake volumes of the first gas supply pipe 131, the second gas supply pipe 132, and the third gas supply pipe 133 are initially set to be the same. For instance, as the etching amount of the wafer 50 gradually decreases from the center region to the edge region, in order to improve the etching uniformity of the wafer 50, the intake volumes of the first gas supply pipe 131 and the second gas supply pipe 132 are increased. For example, the ratio of the intake volumes of the first gas supply pipe 131, the second gas supply pipe 132, and the third gas supply pipe 133 is set to 5:3:2.

[0060] For example, adjusting the mass ratio of gas components in the mixed gas according to the etching amount of wafer 50 includes: when the mixed gas includes Cl2, SF6 and O2, and when the actual etching amount of wafer 50 is less than the target etching amount of wafer 50, increasing the mass ratio of SF6 in the mixed gas.

[0061] Increasing the mass percentage of SF6 in the mixed gas can increase the amount of F ions generated after the mixed gas is ionized, thereby increasing the etching rate of wafer 50 and the actual etching amount of wafer 50.

[0062] By setting the first mass flow controller 141, the second mass flow controller 142 and the third mass flow controller 143, the flow rate of each gas pipe and the mass ratio of each component gas can be adjusted simultaneously, making the etching gas more controllable and improving the etching uniformity of wafer 50.

[0063] In some examples, such as Figures 1-5 As shown, one of the first air supply pipe 131, the second air supply pipe 132, and the third air supply pipe 133 is located on a different side of the spray head 11, along with the other two of the first air supply pipe 131, the second air supply pipe 132, and the third air supply pipe 133.

[0064] For example, one of the first air supply pipe 131, the second air supply pipe 132, and the third air supply pipe 133 is located on opposite sides of the spray head 11, along with the other two of the first air supply pipe 131, the second air supply pipe 132, and the third air supply pipe 133.

[0065] For example, such as Figure 5 As shown, the first air supply pipe 131 and the second air supply pipe 132 are located on one side of the spray head 11, and the third air supply pipe 133 is located on the other side of the spray head 11. The longitudinal distance between the first air supply pipe 131 and the spray head 11 is equal to the longitudinal distance between the second air supply pipe 132 and the spray head 11. The longitudinal direction is parallel to the direction of the central axis L1 of the spray head 11, that is, the first air supply pipe 131 and the second air supply pipe 132 are set at the same height.

[0066] For example, such as Figure 9 As shown, the longitudinal distance between the first air supply pipe 131 and the spray head 11 is not equal to the longitudinal distance between the second air supply pipe 132 and the spray head 11, that is, the first air supply pipe 131 and the second air supply pipe 132 can be arranged vertically.

[0067] like Figure 7As shown, when the spray head 11 is provided with two air inlets, for example, the spray head 11 may include: a first air supply pipe 131, a first air chamber 121 and a first air outlet 1011 connected in sequence, and a second air supply pipe 132, a second air chamber 122 and a second air outlet 1012 connected in sequence; in this way, the spray head 11 only needs to be provided with two air inlets, the first air supply pipe 131 and the second air supply pipe 132. In the specific application of the air inlet structure 10, the spray head 11 is surrounded by an array of heating air pipes that heat the spray head 11. After setting two air supply pipes between the two heating air pipes, there is no extra space to set a third air inlet pipe; therefore, considering the space arrangement problem of the pipes around the spray head 11, the three air inlet pipes can be connected to the corresponding air chambers from different directions, so that the three air supply pipes are not concentrated on the same side of the spray head 11, avoiding interference between these pipes and making the arrangement of the multiple pipes of the spray head 11 more reasonable.

[0068] In some examples, such as Figure 1 and Figure 10 As shown, Figure 10 According to Figure 3 A cross-sectional view of the provided air intake structure 10 along the cross-section line CC shows that the number of third air outlets 1013 is less than the number of second air outlets 1012, and the number of second air outlets 1012 is less than or equal to the number of first air outlets 1011.

[0069] For example, taking the edge region, middle region, and center region of the spray head 11 as having approximately the same radial dimensions, the center region of the spray head 11 has a smaller space compared to the edge region and middle region. Therefore, the number of third air outlets 1013 can be reduced. The third air outlets 1013 are closer to the central axis L1 of the spray head 11. The radius r1 of the ring containing multiple third air outlets 1013 is smaller than the radius r2 of the ring containing multiple second air outlets 1012. The radius r2 of the ring containing multiple second air outlets 1012 is smaller than the radius r3 of the ring containing multiple first air outlets 1011. By setting the numerical relationship between the third air outlets 1013, the second air outlets 1012, and the first air outlets 1011, the third air outlets 1013, the second air outlets 1012, and the first air outlets 1011 can be arranged in approximately the same interval, making the overall arrangement of the air outlets more uniform. Similarly, the space in the central region of wafer 50 is small, and the amount of etching gas required is small. Therefore, by setting the minimum number of third vent holes 1013, the etching gas requirements corresponding to different regions of wafer 50 can be met.

[0070] In some examples, such as Figure 1 and Figure 10As shown, the number of third vents 1013 is 4n+1, the number of second vents 1012 is 4m, and the number of first vents 1011 is 4q, where n is an integer from 0 to 6, m is an integer from 1 to 7, and q is an integer from 1 to 7.

[0071] For example, the number of third vents 1013 can be 1, 5, 9, 13, 17, 21 or 25, etc., and there is no limit here.

[0072] For example, the number of second vents 1012 is 4, 8, 12, 16, 20, 24 or 28, etc., and there is no limitation here.

[0073] For example, the number of first vent holes 1011 is 4, 8, 12, 16, 20, 24 or 28, etc., and there is no limitation here.

[0074] A third vent 1013 is provided at the central axis L1 of the spray head 11, and the other vents are arranged in a manner that is evenly distributed around the central axis L1 of the spray head 11, so that the vents are evenly distributed in the four quadrants, which can improve the overall uniformity of the vent arrangement. In this way, the etching uniformity of the wafer 50 is higher.

[0075] In some examples, such as Figure 1 and Figure 10 As shown, the number of third vents 1013 is 7, the number of second vents 1012 is 12, and the number of first vents 1011 is 12.

[0076] This number of air outlets is easy to manufacture. There are 7 third air outlets 1013. One third air outlet 1013 is set on the central axis L1 of the spray head 11, and the other 6 third air outlets 1013 are evenly arranged around the central axis L1 of the spray head 11. The 6 third air outlets 1013 are evenly distributed on a 360° ring. Similarly, 12 second air outlets 1012 are evenly arranged around the central axis L1 of the spray head 11. The 12 second air outlets 1012 are evenly distributed on a 360° ring. 12 first air outlets 1011 are evenly arranged around the central axis L1 of the spray head 11. The 12 first air outlets 1011 are evenly distributed on a 360° ring.

[0077] In some examples, such as Figure 1 and Figure 10 As shown, the dimensions of the third vent 1013, the second vent 1012, and the first vent 1011 are different from each other.

[0078] For example, the shape of the vent can be circular, elliptical, or oblong, etc., and there is no limitation here. When the vent is circular, the size of the vent is its diameter. When the vent is elliptical, the size of the vent can be either the major axis or the minor axis of the ellipse. When the vent is oblong, the size of the vent can be either the major axis or the minor axis of the oblong shape.

[0079] For example, the size range of the vent is 0.5mm to 5mm. For instance, the size of the vent is 0.5mm, 1mm, 2mm, 3mm, 4mm or 5mm, etc., and there is no limitation here.

[0080] By setting different sizes of the air outlets in different areas of the spray head 11, the size of the air outlets can be adjusted according to the etching amount of the wafer 50. When the etching amount in a certain area of ​​the wafer 50 is small, the size of the air outlet corresponding to that area can be increased, thereby realizing the control of the airflow in different areas of the spray head 11, so that the supply of process gas meets the requirements of the etching uniformity of the wafer 50.

[0081] In some examples, such as Figure 1 and Figure 10 As shown, the size of the third vent 1013 is smaller than the size of the second vent 1012, and the size of the second vent 1012 is smaller than the size of the first vent 1011.

[0082] Since the central area of ​​the spray head 11 has a smaller space compared to the edge and middle areas, the diameter of the third vent 1013 can be smaller. By setting the size relationship of the different types of vents, the etching gas volume requirements of different areas of the wafer 50 can be met, so as to achieve the purpose of uniform etching of the wafer 50.

[0083] In some examples, such as Figure 2 , Figure 3 , Figure 11 and Figure 12 As shown, Figure 11 According to Figure 3 Another cross-sectional view of the provided intake structure 10 along section line CC. Figure 12 According to Figure 3Another cross-sectional view of the provided air intake structure 10 along section line BB shows that the second air outlet 1012 is divided into multiple groups of second air outlets 1012. The distance from the second air outlet 1012 in each group to the central axis L1 of the spray head 11 is equal, while the distance from the second air outlet 1012 in different groups to the central axis L1 of the spray head 11 is different. The second air chamber 122 includes multiple first air distribution chambers 1221 that are isolated from each other. One group of second air outlets 1012 is connected to one first air distribution chamber 1221. The air intake structure 10 also includes multiple second air supply pipes 132. One second air supply pipe 132 is connected to one first air distribution chamber 1221. The air distribution chamber 1221 is connected; and / or, the first air outlet 1011 is divided into multiple groups of first air outlets 1011, the distance from the first air outlet 1011 in each group of first air outlets 1011 to the central axis L1 of the spray head 11 is equal, and the distance from the first air outlet 1011 in different groups to the central axis L1 of the spray head 11 is different. The first air chamber 121 includes: multiple second air distribution chambers 1211 that are isolated from each other, and a group of first air outlets 1011 is connected to a second air distribution chamber 1211. The air intake structure 10 also includes: multiple first air supply pipes 131, and a first air supply pipe 131 is connected to a second air distribution chamber 1211.

[0084] It should be noted that, Figure 10 and Figure 11 These are cross-sectional views obtained along a section line of the intake structure 10 for the two different structures. Figure 10 and Figure 11 The corresponding cross-sectional line is located in the intake structure 10 and Figure 3 The cross-sectional line CC in the air intake structure 10 shown is in the same position; Figure 6 and Figure 12 These are cross-sectional views obtained along a section line of the intake structure 10 for the two different structures. Figure 6 and Figure 12 The corresponding cross-sectional line is located in the intake structure 10 and Figure 3 The cross-sectional line BB in the air intake structure 10 shown is in the same position.

[0085] The distance from the air outlet to the central axis L1 of the spray head 11 is the distance between the geometric center of the air outlet and the central axis L1 of the spray head 11 in the radial direction of the spray head 11.

[0086] For example, when there are two sets of first air outlets 1011, the air outlets of the two sets of first air outlets 1011 can be arranged vertically in the direction of extension of the central axis L1 of the parallel spray head 11.

[0087] In other words, at least two independent second air outlets 1012 can be provided in the middle area of ​​the spray head 11, and / or at least two independent first air outlets 1011 can be provided in the edge area of ​​the spray head 11. Each set of second air outlets 1012 can allow independent air intake, and each set of first air outlets 1011 can allow independent air intake, thereby achieving more refined control of the process gas intake flow rate and ratio by zone, resulting in better etching uniformity of the wafer 50.

[0088] The foregoing preferred embodiments have further illustrated the objectives, technical solutions, and advantages of the present invention. It should be understood that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An air intake structure, characterized in that, The air intake structure is used in semiconductor devices, and the air intake structure includes: a spray head, and a first air chamber, a second air chamber, and a third air chamber that are isolated from each other; The spray head includes a top wall, a side wall, and a bottom wall connected in sequence. The spray head is provided with one or more first air outlets, one or more second air outlets, and one or more third air outlets that are isolated from each other. The distances from the third air outlet, the second air outlet, and the first air outlet to the central axis of the spray head increase sequentially, and the central axis of the spray head passes through one of the one or more third air outlets. The first air outlet extends from the top wall to the side wall, and the second and third air outlets extend from the top wall to the bottom wall. The first air chamber, the second air chamber, and the third air chamber are all connected to the top wall of the spray head. The first air outlet is connected to the first air chamber, the second air outlet is connected to the second air chamber, and the third air outlet is connected to the third air chamber.

2. The intake structure according to claim 1, characterized in that, The air intake structure further includes: a first air supply pipe, a second air supply pipe and a third air supply pipe, wherein the first air supply pipe is connected to the first air chamber, the second air supply pipe is connected to the second air chamber, and the third air supply pipe is connected to the third air chamber; The first gas supply pipe, the second gas supply pipe, and the third gas supply pipe are all used to input the same mixed gas, and the mass ratio of the gas components in the mixed gas is different in at least two of the first gas supply pipe, the second gas supply pipe, and the third gas supply pipe.

3. The intake structure according to claim 2, characterized in that, The mixed gas is used to etch the wafer in the semiconductor device; The air intake structure further includes: a first mass flow controller, a second mass flow controller, and a third mass flow controller, wherein the first mass flow controller is disposed in the first air supply pipe, the second mass flow controller is disposed in the second air supply pipe, and the third mass flow controller is disposed in the third air supply pipe; At least one of the first mass flow controller, the second mass flow controller, and the third mass flow controller adjusts the mass ratio of the gas components in the mixed gas according to the etching amount of the wafer.

4. The intake structure according to claim 3, characterized in that, The step of adjusting the mass ratio of the gas components in the mixed gas according to the etching amount of the wafer includes: When the mixed gas includes NF3 and NH3, and the actual etching amount of the wafer is less than the target etching amount of the wafer, the mass percentage of NF3 in the mixed gas is increased. When the mixed gas includes Cl2, SF6 and O2, and the actual etching amount of the wafer is less than the target etching amount of the wafer, the mass percentage of SF6 in the mixed gas is increased.

5. The intake structure according to any one of claims 2 to 4, characterized in that, One of the first air supply pipe, the second air supply pipe, and the third air supply pipe is located on a different side of the spray head, respectively, from the other two of the first air supply pipe, the second air supply pipe, and the third air supply pipe.

6. The intake structure according to any one of claims 1 to 5, characterized in that, The number of the third air outlet is less than the number of the second air outlet, and the number of the second air outlet is less than or equal to the number of the first air outlet.

7. The intake structure according to any one of claims 1 to 6, characterized in that, The number of the third air outlet is 4n+1, the number of the second air outlet is 4m, and the number of the first air outlet is 4q, where n is an integer from 0 to 6, m is an integer from 1 to 7, and q is an integer from 1 to 7.

8. The intake structure according to any one of claims 1 to 7, characterized in that, The dimensions of the third vent, the second vent, and the first vent are all different.

9. The intake structure according to claim 8, characterized in that, The size of the third vent is smaller than the size of the second vent, and the size of the second vent is smaller than the size of the first vent.

10. The intake structure according to any one of claims 1 to 9, characterized in that, The second air outlet is divided into multiple groups of second air outlets. The distance from each group of second air outlets to the central axis of the spray head is equal, while the distances from different groups of second air outlets to the central axis of the spray head are different. The second air chamber includes: multiple first air distribution chambers isolated from each other; one group of second air outlets communicates with one of the first air distribution chambers. The air intake structure further includes: multiple second air supply pipes; one second air supply pipe communicates with one of the first air distribution chambers; and / or, The first air outlet is divided into multiple groups of first air outlets. The distance from the first air outlet in each group to the central axis of the spray head is equal. The distance from the first air outlet in different groups to the central axis of the spray head is different. The first air chamber includes multiple second air distribution chambers that are isolated from each other. One group of first air outlets is connected to one of the second air distribution chambers. The air intake structure also includes multiple first air supply pipes. One of the first air supply pipes is connected to one of the second air distribution chambers.

11. A semiconductor device, characterized in that, It includes the air intake structure as described in any one of claims 1 to 10.

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