A semiconductor etching apparatus

Abstract

The application provides a semiconductor etching device, which comprises a supporting mechanism for holding a wafer and driving the wafer to rotate, an etching mechanism arranged above the supporting mechanism along a first direction, and a lifting mechanism; the etching mechanism comprises a shell, an etching tube group arranged in the shell, and a heating assembly for keeping the etching liquid in the etching tube group warm; the etching tube group has a spray head penetrating through the bottom of the shell to spray the etching liquid to the surface of the wafer; the lifting mechanism is used for adjusting the relative position of the etching mechanism and the wafer, so that a non-contact working gap is formed between the end of the spray head and the surface of the wafer, and the working gap is greater than or equal to 1 cm and less than 2 cm. The semiconductor etching device disclosed by the application can reduce the temperature difference between the actual temperature of the etching liquid when contacting the wafer and the preset process temperature, can realize efficient and uniform etching on each region of the wafer surface, and can reduce the use amount of the etching liquid.

Description

Technical Field

[0001] This invention relates to the field of semiconductor etching technology, and more particularly to a semiconductor etching apparatus. Background Technology

[0002] In semiconductor manufacturing, etching is a key patterning process associated with photolithography. It primarily employs chemical or physical methods to selectively etch or strip the substrate surface or the thin film covering it. In wet etching processes, sulfuric acid is one of the most widely used chemical fluids, consumed in large quantities, to remove residual photoresist polymers after etching and ion implantation. Furthermore, sulfuric acid is often mixed with other chemical fluids for etching metals such as copper. To further enhance the chemical reaction rate, shorten process time, and improve the removal of stubborn organic residues on the wafer surface, the industry commonly uses high-temperature sulfuric acid processes in these technologies. The high-temperature environment significantly enhances the oxidation and stripping capabilities of sulfuric acid.

[0003] However, in existing wafer etching processes, etching solutions such as sulfuric acid and hydrogen peroxide are typically sprayed onto the rotating wafer via a swing-arm nozzle. Heat is supplied by a heating device on the back of the wafer. After being sprayed from the nozzle, the etching solution cools down by exchanging heat with the surrounding environment before reaching the wafer surface. Furthermore, a temperature difference exists between the wafer surface and the etching solution. During wafer rotation, the etching solution is continuously supplied to the central region and then spreads outwards from the center to the edges using centrifugal force. Because the central region is constantly covered by fresh, warmer etching solution, while the etching solution at the edges experiences a longer flow and cooling time, this further leads to a significant temperature difference between the central and edge areas, ultimately affecting etching uniformity. Meanwhile, in order to ensure uniform etching effect across the entire wafer surface, existing technologies often require extending the etching process time, which leads to a significant increase in the amount of etching solutions such as sulfuric acid. This not only increases the cost of consumables in the process but also further increases the subsequent environmental treatment costs due to the increased amount of waste acid emissions.

[0004] It should be noted that the above description of the background technology is only for the purpose of providing a clear and complete explanation of the technical solutions of the present invention and facilitating understanding by those skilled in the art. It should not be assumed that the above technical solutions are known to those skilled in the art simply because they have been described in the background section of the present invention. Summary of the Invention

[0005] The purpose of this invention is to disclose a semiconductor etching apparatus to solve the problem of significant temperature drop in the prior art when the etching solution cools down before contacting the wafer. In particular, in order to reduce the temperature difference between the actual temperature of the etching solution when it contacts the wafer and the preset process temperature, efficient and uniform etching can be achieved on all areas of the wafer surface, reducing the amount of etching solution used.

[0006] To achieve the above objectives, the present invention provides a semiconductor etching apparatus, comprising: a support mechanism for holding a wafer and driving the wafer to rotate, an etching mechanism disposed above the support mechanism along a first direction, and a lifting mechanism;

[0007] The etching mechanism includes: a housing, an etching tube assembly disposed within the housing, and a heating component for keeping the etching solution within the etching tube assembly warm;

[0008] The etching tube assembly has a nozzle that penetrates the bottom of the housing to spray etching liquid onto the wafer surface;

[0009] The lifting mechanism is used to adjust the relative position of the etching mechanism and the wafer so that a non-contact working gap is formed between the nozzle tip and the wafer surface, and the working gap is greater than or equal to 1 cm and less than 2 cm.

[0010] As a further improvement of the present invention, the etching tube assembly includes at least one set of mixing lines;

[0011] The mixing pipeline is used to mix at least two chemical fluids to form a first etching solution, and the mixing pipeline has a first nozzle at its end for spraying the first etching solution onto the wafer surface.

[0012] As a further improvement of the present invention, the etching tube assembly further includes at least one set of single-liquid pipelines;

[0013] The single-liquid pipeline is used to transport a second etching solution having a predetermined composition, and the single-liquid pipeline has a second nozzle at its end for spraying the second etching solution onto the wafer surface;

[0014] The second etching solution of the predetermined components is configured as a single chemical fluid or as a premix of at least two chemical fluids.

[0015] As a further improvement of the present invention, the mixing pipeline includes a main pipeline and at least one branch pipeline;

[0016] The main pipeline is used to transport the first chemical fluid, and the branch pipeline is used to transport the second chemical fluid. The branch pipeline is connected to the main pipeline so that the second chemical fluid is incorporated into the main pipeline and mixed with the first chemical fluid to form the first etching solution.

[0017] As a further improvement of the present invention, the lifting mechanism is configured to drive the etching mechanism to move up and down relative to the support mechanism along the first direction, so as to drive the nozzle to move to a preset working position above the wafer surface, thereby forming the working gap between the nozzle tip and the wafer surface.

[0018] As a further improvement of the present invention, the heating component is disposed below the etching tube assembly along the first direction, and the heating component surrounds at least a portion of the nozzle.

[0019] As a further improvement of the present invention, the housing includes: a support plate, a fixing ring disposed around the outer periphery of the support plate, and an upper cover and a lower cover respectively disposed on the upper and lower sides of the fixing ring along a first direction.

[0020] The upper cover and the support plate enclose each other to form a first accommodating cavity for accommodating the etching tube assembly, and the lower cover and the support plate enclose each other to form a second accommodating cavity for accommodating the heating assembly.

[0021] The spray path of the nozzle passes sequentially through the support plate, the second accommodating cavity, and the lower cover to spray etching liquid onto the wafer surface.

[0022] As a further improvement of the present invention, the nozzle is configured as a liquid outlet pipe with a hollow structure;

[0023] The lower end of the liquid outlet pipe is integrally formed with the lower cover, and the upper end of the liquid outlet pipe passes upward through the second accommodating cavity and the support plate to extend into the first accommodating cavity to communicate with the etching tube assembly.

[0024] As a further improvement of the present invention, the housing further includes a heat-conducting plate, which is disposed in the second accommodating cavity and fixed to the lower surface of the support plate by a connector;

[0025] The heating assembly is housed in the heat-conducting plate, and the heating assembly includes a plurality of concentrically arranged heating elements, the inner diameter of which increases sequentially from the inside to the outside.

[0026] The heat-conducting plate and the support plate have two aligned through holes to form a channel through which the liquid supply pipe passes.

[0027] As a further improvement of the present invention, the mixing pipeline includes a main pipeline, at least one branch pipeline, and at least one mixer disposed on the main pipeline.

[0028] The main pipeline is used to transport the first chemical fluid, and the branch pipeline is used to transport the second chemical fluid. The branch pipeline is connected to the mixer so that the second chemical fluid is channeled into the main pipeline via the mixer and mixed with the first chemical fluid to form the first etching solution.

[0029] Compared with the prior art, the beneficial effects of the present invention are:

[0030] The etching mechanism and / or the support mechanism are driven to move up and down along a first direction by a lifting mechanism, so that the tip of the nozzle reaches a preset working gap with the wafer surface. This working gap is non-contact; in this embodiment, the working gap can be set to be greater than or equal to 1 cm and less than 2 cm. When the preset working gap is reached, the support mechanism drives the wafer to rotate, and at the same time, the etching solution is delivered to the nozzle through the etching tube assembly. The etching solution is sprayed onto the rotating wafer surface by the nozzle and spreads rapidly and evenly to the wafer edge by centrifugal force.

[0031] Compared to existing technologies that use swing-arm nozzles to spray etching solution onto wafer surfaces over long distances, this invention shortens the spraying distance (i.e., the working gap) between the etching solution and the surrounding environment during spraying. This reduces the significant temperature drop caused by prolonged contact with air after spraying, thereby minimizing the temperature difference between the actual temperature of the etching solution upon contact with the wafer and the preset process temperature. This solves the problem of premature cooling and significant temperature drop of the etching solution before contact with the wafer in existing technologies. Simultaneously, the heating component maintains the temperature of the etching solution within the etching tube assembly, suppressing the temperature drop before spraying. This reduces the temperature difference between the actual temperature of the etching solution and the preset process temperature during transport, minimizing heat loss and reducing the decrease in etching solution activity. This improves etching efficiency upon contact with the wafer and reduces the amount of etching solution needed to compensate for activity loss.

[0032] In this invention, the heat loss of the etching solution during its transport within the etching tube assembly and spraying from the nozzle onto the wafer surface is significantly lower than that of traditional transport and spraying methods in the prior art. Furthermore, the close working gap between the nozzle and the wafer ensures that the temperature drop of the etching solution is consistent across all areas of the wafer surface. This reduces the significant temperature difference between the wafer's center and edges, as seen in existing technologies. This lowers the temperature difference between the etching solution in the wafer's center and edge areas, enabling efficient and uniform etching across all areas of the wafer surface. Consequently, the overall process time is shortened, eliminating the need to compensate for poor local etching results by extending the etching time as in existing technologies. Moreover, compared to existing technologies, the amount of etching solution (such as sulfuric acid and hydrogen peroxide) used is reduced, lowering the cost of etching solution and correspondingly reducing waste acid emissions from the etching process. This achieves cost savings and environmental protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a schematic diagram of the semiconductor etching device disclosed in the present invention;

[0034] Figure 2 It is a top view of the etching tube group;

[0035] Figure 3 It is a schematic diagram of forming a non-contact working gap between the end of the nozzle and the wafer surface;

[0036] Figure 4 It is a cross-sectional view of the nozzle and the wafer;

[0037] Figure 5 It is a schematic diagram that the semiconductor etching device further includes at least one swing arm mechanism and a nozzle;

[0038] Figure 6 It is a schematic diagram for comparing the etching solution temperature control effects between an embodiment of the present invention and the prior art; this figure shows the correlation trend of the temperature difference between the actual temperature of the etching solution when contacting the wafer surface and the preset process temperature with the spraying distance between the end of the nozzle and the wafer surface changing. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0039] The present invention will be described in detail below in conjunction with the embodiments shown in the drawings. However, it should be noted that these embodiments are not limitations to the present invention. Any equivalent transformation or substitution in terms of function, method, or structure made by those of ordinary skill in the art based on these embodiments shall fall within the protection scope of the present invention.

[0040] The drawings in the present invention are not strictly drawn according to the actual ratio, and the specific dimensions of each structure can be determined according to actual needs. The drawings described in the present invention are only schematic diagrams. The lines shown in the drawings included in the specification of the present invention can be understood as components having a certain actual thickness.

[0041] Please refer to Figures 1 to 6 It is a specific embodiment of a semiconductor etching device disclosed in the present invention.

[0042] Refer to Figures 1 to 4As shown, in this embodiment, the semiconductor etching apparatus 100 includes: a support mechanism 10 for holding the wafer 200 and driving the wafer 200 to rotate, an etching mechanism 20 disposed above the support mechanism 10 along a first direction, and a lifting mechanism 30; the etching mechanism 20 includes: a housing 21, an etching tube assembly 22 disposed within the housing 21, and a heating component 23 for keeping the etching liquid in the etching tube assembly 22 warm; the etching tube assembly 22 has a nozzle 221 that penetrates the bottom of the housing 21 to spray etching liquid onto the wafer surface 201; the lifting mechanism 30 is used to adjust the relative position of the etching mechanism 20 and the wafer 200 so that a non-contact working gap L is formed between the end of the nozzle 221 and the wafer surface 201, and the working gap L is greater than or equal to 1 cm and less than 2 cm.

[0043] The support mechanism 10 is used to hold the wafer 200 horizontally and is configured to drive the wafer 200 to rotate about its central axis Q. During etching, rotating the wafer 200 helps the etching solution spread evenly on the wafer surface. The lifting mechanism 30 is used to drive the etching mechanism 20 and / or the support mechanism 10 along a first direction (e.g., Figure 1 The etching mechanism 20 moves vertically in the direction indicated by the central axis Z, parallel to the central axis Q of the wafer 200. The relative vertical distance between the etching mechanism 20 and the wafer 200 is precisely adjusted by the lifting mechanism 30. The etching tube assembly 22 is used to transport and spray the etching solution. During operation, the etching solution is transported through the etching tube assembly 22 to the nozzle 221, and then sprayed from the nozzle 221 onto the wafer surface 201 below. The heating assembly 23 is used to keep the etching tube assembly 22 warm, reducing heat loss of the etching solution during transport.

[0044] In actual operation, the semiconductor etching apparatus 100 disclosed in this invention first places the wafer 200 on the support mechanism 10. Then, the lifting mechanism 30 is activated to drive the etching mechanism 20 and / or the support mechanism 10 to move up and down along a first direction, so that the end of the nozzle 221 reaches a preset working gap L with the wafer surface 201. This working gap L is non-contact; in this embodiment, the working gap L can be set to be greater than or equal to 1 cm and less than 2 cm. When the preset working gap L is reached, the support mechanism 10 drives the wafer 200 to rotate, and simultaneously, the etching solution is delivered to the nozzle 221 through the etching tube assembly 22. The etching solution is sprayed by the nozzle 221 onto the rotating wafer surface 201, and rapidly and evenly spreads to the wafer edge by centrifugal force.

[0045] Compared to existing technologies that use swing-arm nozzles to spray etching solution onto the wafer surface from a distance, this invention shortens the spraying distance (i.e., the working gap L) between the etching solution and the surrounding environment during spraying. This reduces the significant temperature drop caused by prolonged contact with air after spraying, thereby reducing the temperature difference between the actual temperature of the etching solution and the preset process temperature when it contacts the wafer 200. This solves the problem of the etching solution cooling down significantly before contacting the wafer in existing technologies. Simultaneously, the heating component 23 keeps the etching solution in the etching tube assembly 22 warm, suppressing the temperature drop of the etching solution before spraying. This reduces the temperature difference between the actual temperature of the etching solution and the preset process temperature during transport, minimizing the reduction in etching solution activity due to heat loss, improving etching efficiency when the etching solution contacts the wafer, and reducing the amount of etching solution needed to compensate for activity loss.

[0046] In this invention, the heat loss of the etching solution during its transport within the etching tube assembly 22 and spraying from the nozzle 221 onto the wafer surface 201 is significantly lower than that of conventional transport and spraying methods in the prior art. Furthermore, the close working gap L between the nozzle 221 and the wafer 200 ensures that the temperature drop of the etching solution is consistent across all areas of the wafer surface 201. This reduces the significant temperature difference between the wafer's center and edges, as seen in existing technologies, thereby lowering the temperature difference between the etching solution in the center and edge areas of the wafer 200. This allows for efficient and uniform etching across all areas of the wafer surface 201, correspondingly shortening the overall process time. Unlike existing technologies, there is no need to extend the etching time to compensate for poor local etching results. Moreover, compared to existing technologies, the amount of etching solution (such as sulfuric acid and hydrogen peroxide) used is reduced, lowering the cost of the etching solution. Consequently, the amount of waste acid generated during the etching process is also reduced, achieving cost savings and environmental protection.

[0047] In the present invention, the working gap L is designed to achieve close-range spraying of the etching solution and reduce the heat loss of the etching solution before it reaches the wafer surface 201. Exemplarily, the working gap L can be non-integer values such as 1.1 cm, 1.2 cm, 1.3 cm, 1.4 cm, 1.5 cm, 1.6 cm, 1.7 cm, 1.8 cm or 1.9 cm, or the integer value 1 cm, or a range defined by at least two non-integer values, or a range defined by an integer value and at least two non-integer values; for example, the working gap L is greater than 1.1 cm and less than or equal to 1.5 cm, or the working gap L is greater than 1.6 cm and less than or equal to 1.9 cm, or the working gap L is greater than or equal to 1.1 cm and less than or equal to 1.9 cm, or the working gap L is greater than 1 cm and less than 1.9 cm, or the working gap L is greater than or equal to 1 cm and less than 1.5 cm, or the working gap L is greater than or equal to 1 cm and less than 1.3 cm, and other numerical ranges.

[0048] It should be noted that in this embodiment, the supporting mechanism 10 is selected as a conventional wafer supporting device with the functions of clamping and driving the rotation of the wafer 200, which will not be elaborated here. A liquid collecting tank (not labeled) is arranged around the supporting mechanism 10 to collect the etching solution and the wafer cleaning solution, and there is also a waste liquid tank (not labeled) in the semiconductor etching device 100 for the medicine in the liquid collecting tank to flow in.

[0049] See Figure 6 as shown Figure 6 FIG. is a schematic diagram comparing the etching solution temperature control effects between an embodiment of the present invention and the prior art. This figure shows the correlation trend of the temperature difference between the actual temperature of the etching solution when it contacts the wafer surface and the preset process temperature, varying with the spraying distance (i.e., the working gap L) between the end of the nozzle and the wafer surface. As Figure 6 shown, the trend line (blue line) representing the present invention呈现出近似水平的形态.表明在该近距离喷洒范围内,刻蚀液在接触晶圆表面时的实际温度与预设工艺温度的温差始终维持在波动范围极窄的水平。其原因在于,本发明通过缩短刻蚀液从喷头221喷出至接触晶圆表面201的喷洒距离(即工作间隙L),以减少刻蚀液在喷洒过程中与周围环境的热交换,避免刻蚀液喷出后因长时间接触空气导致的大幅降温,从而减小刻蚀液在接触晶圆200时的实际温度与预设工艺温度之间的温差。呈现出近似水平的形态.表明在该近距离喷洒范围内,刻蚀液在接触晶圆表面时的实际温度与预设工艺温度的温差始终维持在波动范围极窄的水平。其原因在于,本发明通过缩短刻蚀液从喷头221喷出至接触晶圆表面201的喷洒距离(即工作间隙L),以减少刻蚀液在喷洒过程中与周围环境的热交换,避免刻蚀液喷出后因长时间接触空气导致的大幅降温,从而减小刻蚀液在接触晶圆200时的实际温度与预设工艺温度之间的温差。呈现出近似水平的形态.表明在该近距离喷洒范围内,刻蚀液在接触晶圆表面时的实际温度与预设工艺温度的温差始终维持在波动范围极窄的水平。其原因在于,本发明通过缩短刻蚀液从喷头221喷出至接触晶圆表面201的喷洒距离(即工作间隙L),以减少刻蚀液在喷洒过程中与周围环境的热交换,避免刻蚀液喷出后因长时间接触空气导致的大幅降温,从而减小刻蚀液在接触晶圆200时的实际温度与预设工艺温度之间的温差。呈现出近似水平的形态.表明在该近距离喷洒范围内,刻蚀液在接触晶圆表面时的实际温度与预设工艺温度的温差始终维持在波动范围极窄的水平。其原因在于,本发明通过缩短刻蚀液从喷头221喷出至接触晶圆表面201的喷洒距离(即工作间隙L),以减少刻蚀液在喷洒过程中与周围环境的热交换,避免刻蚀液喷出后因长时间接触空气导致的大幅降温,从而减小刻蚀液在接触晶圆200时的实际温度与预设工艺温度之间的温差。呈现出近似水平的形态.表明在该近距离喷洒范围内,刻蚀液在接触晶圆表面时的实际温度与预设工艺温度的温差始终维持在波动范围极窄的水平。其原因在于,本发明通过缩短刻蚀液从喷头221喷出至接触晶圆表面201的喷洒距离(即工作间隙L),以减少刻蚀液在喷洒过程中与周围环境的热交换,避免刻蚀液喷出后因长时间接触空气导致的大幅降温,从而减小刻蚀液在接触晶圆200时的实际温度与预设工艺温度之间的温差。呈现出近似水平的形态.表明在该近距离喷洒范围内,刻蚀液在接触晶圆表面时的实际温度与预设工艺温度的温差始终维持在波动范围极窄的水平。其原因在于,本发明通过缩短刻蚀液从喷头221喷出至接触晶圆表面201的喷洒距离(即工作间隙L),以减少刻蚀液在喷洒过程中与周围环境的热交换,避免刻蚀液喷出后因长时间接触空气导致的大幅降温,从而减小刻蚀液在接触晶圆200时的实际温度与预设工艺温度之间的温差。呈现出近似水平的形态.表明在该近距离喷洒范围内,刻蚀液在接触晶圆表面时的实际温度与预设工艺温度的温差始终维持在波动范围极窄的水平。其原因在于,本发明通过缩短刻蚀液从喷头221喷出至接触晶圆表面201的喷洒距离(即工作间隙L),以减少刻蚀液在喷洒过程中与周围环境的热交换,避免刻蚀液喷出后因长时间接触空气导致的大幅降温,从而减小刻蚀液在接触晶圆200时的实际温度与预设工艺温度之间的温差。呈现出近似水平的形态.表明在该近距离喷洒范围内,刻蚀液在接触晶圆表面时的实际温度与预设工艺温度的温差始终维持在波动范围极窄的水平。其原因在于,本发明通过缩短刻蚀液从喷头221喷出至接触晶圆表面201的喷洒距离(即工作间隙L),以减少刻蚀液在喷洒过程中与周围环境的热交换,避免刻蚀液喷出后因长时间接触空气导致的大幅降温,从而减小刻蚀液在接触晶圆200时的实际温度与预设工艺温度之间的温差。呈现出近似水平的形态.表明在该近距离喷洒范围内,刻蚀液在接触晶圆表面时的实际温度与预设工艺温度的温差一直保持在 a nearly horizontal shape. It shows that within this close-range spraying range, the temperature difference between the actual temperature of the etching solution when it contacts the wafer surface and the preset process temperature remains at a very narrow fluctuation range. The reason is that the present invention reduces the heat exchange between the etching solution and the surrounding environment during the spraying process by shortening the spraying distance (i.e., the working gap L) from the nozzle 221 of the etching solution to the contact with the wafer surface 201, avoids the significant temperature drop of the etching solution due to long-term contact with air after spraying, and thus reduces the temperature difference between the actual temperature of the etching solution when it contacts the wafer 200 and the preset process temperature.

[0050] In stark contrast, the trend line (red line) representing existing technologies (e.g., swing-arm nozzles) exhibits a significantly positive upward slope within its typical spraying distance range (e.g., 10cm to 30cm). This clearly demonstrates that the temperature difference between the actual temperature of the etching solution upon contact with the wafer surface and the preset process temperature increases dramatically with increasing spraying distance. This phenomenon objectively reflects that during long-distance spraying, the etching solution experiences significant heat loss due to prolonged contact with ambient air, resulting in a substantial temperature drop before even contacting the wafer.

[0051] In conclusion, Figure 6 The comparison results directly demonstrate that by limiting the working gap L to a range of 1 cm or more and less than 2 cm, the present invention can reduce the temperature difference between the actual temperature of the etching solution when it contacts the wafer and the preset process temperature, thereby solving the problem of liquid temperature drop caused by long-distance spraying in the prior art.

[0052] In some examples, the parameter Figure 2 and Figure 4 As shown, the etching tube assembly 22 includes at least one set of mixing lines 222; the mixing lines 222 are used to mix at least two chemical fluids to form a first etching solution, and the mixing lines 222 have a first nozzle 223 at their end for spraying the first etching solution onto the wafer surface 201.

[0053] This invention, by setting up a mixing pipeline 222, allows for the online mixing of two or more chemical fluids (such as sulfuric acid and hydrogen peroxide) before spraying (i.e., mixing occurs during the process of transporting the fluid to the first nozzle 223 via the mixing pipeline 222) to form a first etching solution. This ensures that the first etching solution sprayed from the first nozzle 223 has higher chemical activity. Compared to using premixed liquids, this allows for the removal of photoresist and other residues at a faster etching rate, thereby achieving the desired process effect in a shorter time.

[0054] Meanwhile, the mixing pipeline 222 is within the heat preservation range of the heating component 23. The heating component 23 can keep the mixing process of the chemical fluid in the mixing pipeline 222 and the first etching solution formed by the mixture warm, so as to suppress the heat loss of the first etching solution in the entire process of mixing and transportation, so that the temperature of the first etching solution before spraying can be stably maintained at a level close to the preset process temperature, and maintain the chemical activity and etching efficiency of the first etching solution when it contacts the wafer.

[0055] The nozzle 221 includes a first nozzle 223. A non-contact working gap L is formed between the end of the first nozzle 223 and the wafer surface 201. The first etching solution, mixed through the mixing pipe 222, is sprayed onto the wafer surface 201 at close range through the first nozzle 223. This reduces heat exchange between the first etching solution and the surrounding environment during spraying, preventing a significant temperature drop due to prolonged contact with air after spraying. This reduces the temperature difference between the actual temperature of the first etching solution upon contact with the wafer 200 and the preset process temperature. This ensures that the temperature drop of the first etching solution is relatively uniform across all areas of the wafer surface 201, thereby reducing the temperature difference between the central and edge areas of the wafer 200 and enabling efficient and uniform etching across all areas of the wafer surface 201.

[0056] In some examples, the parameter Figure 2 As shown, the mixing pipeline 222 includes a main pipeline 2221 and at least one branch pipeline 2222; the main pipeline 2221 is used to transport a first chemical fluid, and the branch pipeline 2222 is used to transport a second chemical fluid. The branch pipeline 2222 is connected to the main pipeline 2221 so that the second chemical fluid is drawn into the main pipeline 2221 and mixed with the first chemical fluid to form a first etching solution.

[0057] Different chemical fluids are transported via a main pipeline 2221 and at least one branch pipeline 2222. The branch pipeline 2222 is directly connected to the main pipeline 2221, allowing the second chemical fluid to directly flow into the first chemical fluid in the main pipeline 2221 under transport pressure. The flow kinetic energy of the first and second chemical fluids enables natural mixing within the main pipeline 2221, achieving an online mixing effect that is achieved on-demand. Compared to pre-mixing, this method eliminates the long-distance transport of the mixed solution, avoiding component stratification and decomposition of effective components during transport, and ensuring the uniformity of the first etching solution concentration after mixing. Furthermore, the mixing ratio of the first and second chemical fluids can be flexibly controlled by adjusting the flow rates of each chemical fluid in the main pipeline 2221 and branch pipeline 2222, according to the specific requirements of different etching processes, achieving precise adjustment of the first etching solution mixing ratio. Moreover, some chemical fluids may be unstable or more corrosive after mixing. By transporting multiple chemical fluids separately through the main pipeline 2221 and at least one branch pipeline 2222, and mixing only in the main pipeline 2221, the residence time of unstable or more corrosive mixtures in the entire device pipeline can be reduced, thereby reducing safety risks caused by pipeline corrosion, leakage and other problems, and improving the safety and reliability of the whole machine.

[0058] The mixing conduit 222 can be configured in various ways to achieve the mixing of at least two chemical fluids. In the basic configuration for mixing two chemical fluids, the mixing conduit 222 can be constructed in various geometries. For example, in one embodiment, the mixing conduit 222 can be constructed as a T-shaped structure. Specifically, as... Figure 2 As shown, the flow path of branch line 2222 is configured to intersect the flow path of main line 2221 approximately perpendicularly to allow the second chemical fluid to be injected laterally into main line 2221. In another embodiment not shown, mixing line 222 can also be configured as a Y-shape. Specifically, main line 2221 and branch line 2222 merge at a junction point and together form a single downstream output line for conveying the mixed etching solution.

[0059] When it is necessary to mix three or more chemical fluids, the above-mentioned basic structure can be expanded. For example, two or more branch pipes 2222 can be connected at different locations of a main pipe 2221 or at different orientations of the same cross section to form a multi-injection manifold structure (not shown).

[0060] It should be understood that the structure of the mixing line 222 is not limited to the example described above. Any piping structure capable of introducing, mixing, and discharging two or more chemical fluids, such as, but not limited to, tangential injection or coaxial sleeve piping structures, falls within the scope of protection of this invention.

[0061] In a preferred embodiment of the present invention for mixing two chemical fluids, a T-shaped structure is used. More specifically, the outlet of the branch pipe 2222 opens into the side wall of the main pipe 2221, which can induce local eddies in the main pipe 2221, thereby achieving rapid and thorough mixing of the two chemical fluids and ensuring the uniformity of the first etching solution when it finally reaches the first nozzle 223.

[0062] In some examples, the parameter Figure 2 As shown, the mixing pipeline 222 includes a main pipeline 2221, at least one branch pipeline 2222, and at least one mixer 2223 disposed on the main pipeline 2221. The main pipeline 2221 is used to transport a first chemical fluid, and the branch pipeline 2222 is used to transport a second chemical fluid. The branch pipeline 2222 is connected to the mixer 2223 so that the second chemical fluid is drawn into the main pipeline 2221 via the mixer 2223 and mixed with the first chemical fluid to form a first etching solution. The mixer 2223 is provided with a plurality of interfaces 22231 for connecting to the branch pipeline 2222.

[0063] The mixer 2223 provides an independent mixing chamber for the first and second chemical fluids, replacing the direct connection between the main pipeline 2221 and the branch pipelines 2222. The mixer 2223 serves as a unified junction point, ensuring that the chemical fluids from the main pipeline 2221 and all branch pipelines 2222 are mixed at this point before flowing into the downstream main pipeline 2221'. The first and second chemical fluids are mixed within the mixer 2223 through its internal chamber channels (not shown), ensuring a highly uniform composition and concentration of the first etching solution. This guarantees a consistent etching reaction rate across all areas of the wafer surface 201 during the first etching solution preparation process, further improving etching uniformity. Meanwhile, according to the different etching processes and their requirements for the first etching solution ratio, the mixing ratio of the first chemical fluid and the second chemical fluid can be flexibly controlled by adjusting the flow rate of each chemical fluid in the main pipeline 2221 and the branch pipeline 2222, thereby achieving fine adjustment of the mixing ratio of the first etching solution.

[0064] In some examples, the parameter Figure 2 As shown, the mixing line 222 includes: a main line 2221, at least two branch lines 2222, and a mixer 2223 connected in series in the main line 2221. The main line 2221 is divided into an upstream section (not labeled) and a downstream section (not labeled), connected by the mixer 2223. The upstream section is used to deliver a first chemical fluid to the mixer 2223. One branch line 2222 is configured to directly inject the second chemical fluid it delivers into the upstream section of the main line 2221. The other branch line (not shown) is configured to inject the third chemical fluid it delivers into the mixer 2223. The operation is as follows: First, the first chemical fluid and the second chemical fluid are initially mixed in the upstream section of the main line 2221. Then, the initially mixed etching solution flows into the mixer 2223. At the same time, the third chemical fluid is also independently injected into the mixer 2223 through the other branch line. Inside the mixer 2223, the initially mixed etching solution is mixed with the third chemical fluid. Finally, the fully mixed etching solution flows out of the mixer 2223, enters the downstream section of the main pipeline 2221, and is delivered to the nozzle 221.

[0065] It should be noted that the mixing pipeline 222 of the present invention can be configured with multiple branch pipelines 2222 on the main pipeline 2221 or multiple branch interfaces 22231 on the mixer 2223 to connect to the branch pipelines 2222 according to different etching process requirements, so as to achieve synchronous mixing of three or more chemical fluids. Each branch pipeline 2222 can be used to independently transport one chemical fluid. By precisely controlling the flow of each branch pipeline 2222 to the main pipeline 2221 or the mixer 2223, complex etching solutions composed of three or more chemical fluids can be prepared online. This improves the process compatibility and versatility of the etching assembly 22 and the semiconductor etching apparatus 100, enabling the semiconductor etching apparatus 100 to cover a wider range of processes and avoiding the need to replace or expand device components for different processes.

[0066] In some examples, the parameter Figure 2 As shown, the etching tube assembly 22 also includes at least one set of single-liquid lines 224; the single-liquid lines 224 are used to deliver a second etching solution having a predetermined composition, and the single-liquid lines 224 have a second nozzle 225 at their end for spraying the second etching solution onto the wafer surface 201; the second etching solution with the predetermined composition is configured as a single chemical fluid or is pre-mixed from at least two chemical fluids.

[0067] By adding at least one set of single-liquid pipelines 224 to the etching tube assembly 22, and configuring them with an independent second nozzle 225 separate from the first nozzle 223, the first nozzle 223 and the second nozzle 225 do not interfere with each other and are independently controlled. The single-liquid pipeline 224 can flexibly transport a single chemical fluid or an etching solution premixed from at least two chemical fluids to adapt to the etching solution requirements of different processes in semiconductor wet etching. Furthermore, the single-liquid pipeline 224 can directly use standard chemical fluids (i.e., the second etching solution) that have been premixed in the factory. For chemical fluids that do not require online mixing, they can be directly transported through the single-liquid pipeline 224, improving the versatility of the semiconductor etching apparatus 100. In addition, if the mixing pipeline 222 fails, the single-liquid pipeline 224 can also serve as a backup or emergency etching solution transport channel (using premixed etching solution) to ensure production continuity and improve the reliability of the semiconductor etching apparatus 100.

[0068] The single-liquid pipeline 224 and the mixing pipeline 222 are integrated into the same etching tube assembly 22. The single-liquid pipeline 224 and the mixing pipeline 222 share the same housing 21 and the same lifting mechanism 30, eliminating the need for separate conveying, spraying, and heat preservation equipment for the single-liquid pipeline 224. During the wafer etching process, the rapid switching or simultaneous spraying of the first and second etching solutions can be achieved by simply adjusting the fluid delivery switches of the single-liquid pipeline 224 and the mixing pipeline 222. This eliminates the need to transfer the wafer 200 or adjust the device structure, enabling continuous implementation of multi-step etching processes, improving etching efficiency, and reducing the risk of secondary contamination during wafer transfer.

[0069] The nozzle 221 also includes a second nozzle 225. A non-contact working gap L is formed between the end of the second nozzle 225 and the wafer surface 201. The second etchant is delivered via a single-liquid conduit 224. The second nozzle 225 sprays the etchant onto the wafer surface 201 at close range, reducing heat exchange between the etchant and the surrounding environment during spraying. This avoids a significant temperature drop caused by prolonged contact with air after spraying, thus reducing the temperature difference between the actual temperature of the etchant upon contact with the wafer 200 and the preset process temperature. This ensures that the temperature drop of the etchant is relatively uniform across all areas of the wafer surface 201, thereby reducing the temperature difference between the central and edge areas of the wafer 200 and enabling efficient and uniform etching across all areas of the wafer surface 201.

[0070] It should be noted that the end spray nozzles (not marked) of the first nozzle 223 and the second nozzle 225 facing the wafer surface 201 are reference points. The arrangement of the line formed between the two reference points is not particularly limited and can be flexibly set according to the etching process requirements. At the same time, there is no restriction on whether the line passes through the center of the wafer 200. It can adapt to the spraying requirements of different areas of the wafer surface 201. With the rotation of the wafer, the first etching solution and / or the second etching solution can be uniformly etched in all areas of the wafer surface 201, avoiding the problem of insufficient etching in local areas of the wafer 200.

[0071] In some examples, the single-liquid line 224 can also be used to deliver cleaning fluid (e.g., ultrapure water). For example, the single-liquid line 224 can be specifically used for rinsing or final cleaning steps.

[0072] In some examples, the parameter Figure 5As shown, the semiconductor etching apparatus 100 also includes at least one swing arm mechanism 40 and a nozzle 41. The nozzle 41 is mounted on the top of the swing arm mechanism 40, and the swing arm mechanism 40 swings back and forth to cover the wafer surface 201 with the etching solution or cleaning solution sprayed by the nozzle 41. The swing arm mechanism 40 and the nozzle 41 cooperate to spray a supplementary processing solution (such as DIW, SCI, IPA solution, etc.) to perform pre-wetting or cleaning operations. The swing arm mechanism 40 and the nozzle 41 can also be configured as a two-fluid nozzle swing arm. This two-fluid nozzle can mix liquid (such as DIW or IPA) with a hot carrier gas (such as hot nitrogen) to form droplets for atomized spraying, thereby achieving efficient cleaning or auxiliary drying of the wafer.

[0073] In some examples, the parameter Figure 1 As shown, the lifting mechanism 30 is configured to drive the etching mechanism 20 to move up and down relative to the support mechanism 10 in a first direction, so as to drive the nozzle 221 to move to a preset working position above the wafer surface 201, so that a working gap L is formed between the end of the nozzle 221 and the wafer surface 201.

[0074] Traditional swing-arm nozzles typically spray at a height of tens of centimeters (e.g., 20 cm) above the wafer. During flight, the fluid exchanges heat with the environment, resulting in a significant temperature drop by the time it reaches the wafer. This invention uses a lifting mechanism 30 to drive the entire etching mechanism 20 downwards in a first direction, moving the end of the nozzle 221 to a preset working position adjacent to the wafer surface 201, thus forming a working gap L. It ensures that both the first nozzle 223 and the second nozzle 225 are perfectly aligned with the working gap L on the wafer surface 201. This shortens the time and spray distance for the etching solution (including the first and second etching solutions) from the nozzle 221 to contact the wafer surface 201, reducing heat exchange between the etching solution and the surrounding environment during spraying. It also prevents a significant temperature drop due to prolonged contact with air after spraying, thereby reducing the temperature difference between the actual temperature of the etching solution upon contact with the wafer 200 and the preset process temperature. This ensures that the temperature drop of the etching solution is basically the same when it is spread to various areas of the wafer surface 201, thereby reducing the temperature difference of the etching solution between the central and edge areas of the wafer 200, and enabling efficient and uniform etching to be achieved in various areas of the wafer surface 201.

[0075] The lifting mechanism 30 (e.g., composed of a servo motor and a precision ball screw) can control and adjust the size of the working gap L with micron-level precision. In the non-operating state, the lifting mechanism 30 can raise the entire etching mechanism 20 to a position away from the wafer 200, providing ample open space for the automatic transfer of the wafer 200 and the cleaning and maintenance of the semiconductor etching apparatus 100, thereby improving the maintainability and ease of operation of the semiconductor etching apparatus 100.

[0076] In some examples, the parameter Figure 4As shown, the heating component 23 is disposed below the etching tube assembly 22 along a first direction, and the heating component 23 surrounds at least a portion of the nozzle 221.

[0077] The close working gap L between the nozzle 221 and the wafer 200 allows the heating component 23 to form a concentrated and stable local thermal field in the working gap L region between the spray nozzle at the end of the nozzle 221 and the wafer surface 201. This provides targeted heating to the spray space above the wafer 200, reducing the temperature difference between the etchant sprayed from the nozzle 221 and the surrounding environment, and minimizing heat exchange during the etchant spraying process. Simultaneously, it increases the local ambient temperature above the wafer surface 201, weakening the secondary temperature drop caused by the temperature difference after the etchant contacts the wafer surface 201, further reducing temperature loss from the etchant and minimizing the overall temperature drop. Furthermore, the heating component 23 can insulate the etchant inside the nozzle 221, reducing heat loss before the etchant exits from the nozzle 221. Moreover, the heating component 23 can insulate each nozzle individually according to the arrangement of the multiple nozzles (i.e., the first nozzle 223 and the second nozzle 225) in the etching tube assembly 22.

[0078] In some examples, the parameter Figures 2 to 4 As shown, the housing 21 includes: a support plate 211, a fixing ring 212 circumferentially disposed on the outer side of the support plate 211, and an upper cover 213 and a lower cover 214 respectively disposed on the upper and lower sides of the fixing ring 212 along a first direction. The upper cover 213 and the support plate 211 enclose a first receiving cavity 215 for accommodating the etching tube assembly 22, and the lower cover 214 and the support plate 211 enclose a second receiving cavity 216 for accommodating the heating assembly 23. The spray path of the nozzle 221 passes through the support plate 211, the second receiving cavity 216, and the lower cover 214 in sequence to spray etching liquid onto the wafer surface 201. The heat generated by the heating assembly 23 during operation can be transferred upward along the support plate 211 to the first receiving cavity 215, thereby keeping the etching tube assembly 22 warm and reducing heat loss of the etching liquid in the etching tube assembly 22 during mixing and transportation. The spray path of the nozzle 221 sequentially passes through the support plate 211, the second accommodating cavity 216, and the lower cover 214. Except for the end spray nozzle, the rest of the nozzle 221 is located inside the housing 21. This ensures that the nozzle 221 is always within the heat preservation range of the heating component 23 in the second accommodating cavity 216. Combined with the heat preservation of the etching tube assembly 22 by the first accommodating cavity 215, continuous heat preservation is achieved throughout the entire pipeline of the etching tube assembly 22 and the nozzle 221, reducing heat loss of the etching solution before mixing and delivery to the spray.

[0079] In some examples, the parameter Figure 3 and Figure 4As shown, the nozzle 221 is configured as a hollow liquid outlet pipe 2211; the lower end of the liquid outlet pipe 2211 is integrally formed with the lower cover 214, and the upper end of the liquid outlet pipe 2211 extends upward through the second accommodating cavity 216 and the support plate 211 to reach the first accommodating cavity 215 and connect to the etching tube assembly 22. The hollow structure of the liquid outlet pipe 2211 provides a delivery channel for the etching fluid. The upper end of the liquid outlet pipe 2211 extends to the first accommodating cavity 215, the middle section passes through the second accommodating cavity 216 and the support plate 211, and the lower end of the liquid outlet pipe 2211 is integrally formed with the lower cover 214. The entire liquid outlet pipe 2211, except for the end spray nozzle, is located inside the housing 21. The first accommodating cavity 215 can keep the upper part of the liquid outlet pipe 2211 warm. The heat from the heating component 23 in the second accommodating cavity 216 can directly act on the middle part of the liquid outlet pipe 2211. Combined with the temperature support formed by the heat conduction of the heating component 23 in the lower cover 214, the etching tube group 22 and the liquid outlet pipe 2211 can be kept warm, reducing the heat loss of the etching solution in the entire process of mixing and transporting.

[0080] In some examples, the parameter Figure 4 As shown, the housing 21 also includes a heat-conducting plate 217, which is disposed within the second accommodating cavity 216 and fixed to the lower surface of the support plate 211 via a connector (not labeled). A heating assembly 23 is housed within the heat-conducting plate 217 and includes several concentrically arranged heating elements 231, the inner diameter of which increases sequentially from the inside to the outside. The heat-conducting plate 217 and the support plate 211 have two aligned through holes (not labeled) to form a channel 219 through which the liquid outlet pipe 2211 passes. The heat-conducting plate 217 evenly conducts heat upwards to the support plate 211, improving the uniformity of the thermal field within the first accommodating cavity 215, ensuring the insulation effect of the etching tube assembly 22, and reducing heat loss. The concentric arrangement of the heating elements 231 with their increasing inner diameters creates a uniform annular thermal field within the second accommodating cavity 216, ensuring uniform heating around the liquid outlet pipe 2211. The through holes of the heat-conducting plate 217 and the support plate 211 are aligned to form a channel 219, which provides a precise guide for the liquid outlet pipe 2211 to pass through.

[0081] The detailed descriptions listed above are merely specific descriptions of feasible embodiments of the present invention, and are not intended to limit the scope of protection of the present invention. All equivalent embodiments or modifications made without departing from the spirit of the present invention should be included within the scope of protection of the present invention.

[0082] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A semiconductor etching apparatus, characterized in that, include: A support mechanism for holding and driving the wafer to rotate, an etching mechanism disposed above the support mechanism along a first direction, and a lifting mechanism; The etching mechanism includes: a housing, an etching tube assembly disposed within the housing, and a heating component for keeping the etching solution within the etching tube assembly warm; The etching tube assembly has a nozzle that penetrates the bottom of the housing to spray etching fluid onto the wafer surface, and the heating assembly surrounds at least a portion of the nozzle; The lifting mechanism is used to adjust the relative position of the etching mechanism and the wafer so that a non-contact working gap is formed between the nozzle tip and the wafer surface, and the working gap is greater than or equal to 1 cm and less than 2 cm.

2. The semiconductor etching apparatus according to claim 1, characterized in that, The etching tube assembly includes at least one set of mixing lines; The mixing pipeline is used to mix at least two chemical fluids to form a first etching solution, and the mixing pipeline has a first nozzle at its end for spraying the first etching solution onto the wafer surface.

3. The semiconductor etching apparatus according to claim 2, characterized in that, The etching tube assembly also includes at least one set of single-liquid lines; The single-liquid pipeline is used to transport a second etching solution having a predetermined composition, and the single-liquid pipeline has a second nozzle at its end for spraying the second etching solution onto the wafer surface; The second etching solution of the predetermined components is configured as a single chemical fluid or as a premix of at least two chemical fluids.

4. The semiconductor etching apparatus according to claim 2, characterized in that, The mixing pipeline includes a main pipeline and at least one branch pipeline; The main pipeline is used to transport the first chemical fluid, and the branch pipeline is used to transport the second chemical fluid. The branch pipeline is connected to the main pipeline so that the second chemical fluid is incorporated into the main pipeline and mixed with the first chemical fluid to form the first etching solution.

5. The semiconductor etching apparatus according to claim 1, characterized in that, The lifting mechanism is configured to drive the etching mechanism to move up and down relative to the support mechanism along the first direction, so as to drive the nozzle to move to a preset working position above the wafer surface, thereby forming the working gap between the nozzle tip and the wafer surface.

6. The semiconductor etching apparatus according to claim 1, characterized in that, The heating component is disposed below the etching tube assembly along the first direction.

7. The semiconductor etching apparatus according to claim 6, characterized in that, The housing includes: a support plate, a fixing ring circumferentially disposed on the outer side of the support plate, and an upper cover and a lower cover respectively disposed on the upper and lower sides of the fixing ring along a first direction. The upper cover and the support plate enclose each other to form a first accommodating cavity for accommodating the etching tube assembly, and the lower cover and the support plate enclose each other to form a second accommodating cavity for accommodating the heating assembly. The spray path of the nozzle passes sequentially through the support plate, the second accommodating cavity, and the lower cover to spray etching liquid onto the wafer surface.

8. The semiconductor etching apparatus according to claim 7, characterized in that, The nozzle is configured as a liquid outlet pipe with a hollow structure; The lower end of the liquid outlet pipe is integrally formed with the lower cover, and the upper end of the liquid outlet pipe passes upward through the second accommodating cavity and the support plate to extend into the first accommodating cavity to communicate with the etching tube assembly.

9. The semiconductor etching apparatus according to claim 7, characterized in that, The housing also includes a heat-conducting plate, which is disposed in the second accommodating cavity and fixed to the lower surface of the support plate by a connector; The heating assembly is housed in the heat-conducting plate, and the heating assembly includes a plurality of concentrically arranged heating elements, the inner diameter of which increases sequentially from the inside to the outside. The heat-conducting plate and the support plate have two aligned through holes to form a channel through which the liquid supply pipe passes.

10. The semiconductor etching apparatus according to claim 2, characterized in that, The mixing pipeline includes a main pipeline, at least one branch pipeline, and at least one mixer installed on the main pipeline. The main pipeline is used to transport the first chemical fluid, and the branch pipeline is used to transport the second chemical fluid. The branch pipeline is connected to the mixer so that the second chemical fluid is channeled into the main pipeline via the mixer and mixed with the first chemical fluid to form the first etching solution.

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