Gating transistor manufacturing method

Abstract

Provided is a gating transistor manufacturing method, comprising: preparing a substrate, and depositing a dielectric layer (2) on an upper side of the substrate (1); depositing a lower electrode layer (3) on an upper side of the dielectric layer, and depositing a first metal layer (4) on an upper side of the lower electrode layer; depositing a resistive switching layer (5) on an upper side of the first metal layer, and depositing a second metal layer (6) on the resistive switching layer; depositing an upper electrode layer (7) on the second metal layer, so as to form a wafer; flipping the wafer, such that the substrate faces upward and the upper electrode layer faces downward; driving the wafer to rotate, and spraying an etching solution onto the substrate, such that the edge of the wafer is impregnated with the etching solution; and at the same time, performing wet etching on the edges of the second metal layer, the resistive switching layer, the first metal layer and the lower electrode layer. Thus, wet etching is performed on the edges of the second metal layer, the resistive switching layer, the first metal layer and the lower electrode layer, and wet etching is more efficient at etching the second metal layer and the first metal layer, with all by-products being soluble, such that the problems of metal exposure and contamination at the edge of the wafer can be solved.

Description

Manufacturing method of the selector tube Cross-references to related applications

[0001] This application claims priority to Chinese patent application filed on July 8, 2024, with application number 202410905203.9 and entitled "Method for Manufacturing a Selector Tube". Technical Field

[0002] This disclosure relates to the field of semiconductor technology, and in particular to a method for manufacturing a gate transistor. Background Technology

[0003] In the manufacturing process of gate transistors, defect sources or metal contamination sources may be generated at the wafer edge, requiring wafer edge etching to remove these defects or metal contamination sources. Current technology uses inclined dry plasma wafer edge etching equipment to etch the wafer edges.

[0004] In related technologies, dry etching produces a slope problem, where a large amount of metal is exposed. When the metal comes into contact with plasma, it causes metal agglomeration, resulting in more severe defect sources or metal contamination sources at the wafer edge, and the residual by-products are difficult to remove. Summary of the Invention

[0005] The embodiments disclosed herein are intended to at least address one of the technical problems existing in the prior art. Therefore, one object of the embodiments disclosed herein is to provide a method for manufacturing a gate tube that can prevent metal contamination.

[0006] A method for manufacturing a selector according to an embodiment of this disclosure includes: preparing a substrate; depositing a dielectric layer on the substrate; depositing a lower electrode layer on the dielectric layer; depositing a first metal layer on the lower electrode layer; depositing a resistive switching layer on the first metal layer; depositing a second metal layer on the resistive switching layer; depositing an upper electrode layer on the second metal layer to form a wafer; flipping the wafer so that the substrate faces upward and the upper electrode layer faces downward; driving the wafer to rotate and spraying an etching solution onto the substrate so that the etching solution wets the edge of the wafer; and simultaneously performing wet etching on the edges of the second metal layer, the resistive switching layer, the first metal layer, and the lower electrode layer.

[0007] Therefore, by performing wet etching on the edges of the second metal layer, resistive switching layer, first metal layer and lower electrode layer, the etching efficiency of the second metal layer and the first metal layer is faster, and the by-products are all soluble, thus solving the problem of metal exposure and contamination at the wafer edge.

[0008] According to some embodiments of this disclosure, the step of simultaneously performing wet etching on the edges of the second metal layer, the resistive switching layer, the first metal layer and the lower electrode layer further includes simultaneously performing wet etching on the edges of the upper electrode layer.

[0009] According to some embodiments of this disclosure, the step of flipping the wafer so that the substrate faces upward and the upper electrode layer faces downward further includes: dry etching the edges of the upper electrode layer.

[0010] According to some embodiments of this disclosure, the material of the first metal layer includes at least one of copper, palladium, silver, gold, and niobium; the material of the second metal layer includes at least one of copper, palladium, silver, gold, and niobium.

[0011] According to some embodiments of this disclosure, the step of driving the wafer to rotate and spraying an etching solution onto the substrate so that the etching solution wets the edge of the wafer further includes: setting the rotational speed of the wafer to n, where n satisfies the relationship: 200RPM≤n≤500RPM.

[0012] According to some embodiments of this disclosure, the step of driving the wafer to rotate and spraying an etching solution onto the substrate so that the etching solution wets the edge of the wafer further includes: setting the flow rate of the etching solution to Q, where Q satisfies the relationship: Q≥1L / min.

[0013] According to some embodiments of this disclosure, the step of driving the wafer to rotate and spraying an etching solution onto the substrate so that the etching solution wets the edge of the wafer further includes: the position of spraying the etching solution onto the substrate is adjustable, and the distance between the position of spraying the etching solution onto the substrate and the center of the substrate is L, where L satisfies the relationship: 50mm≤L≤100mm.

[0014] According to some embodiments of this disclosure, the step of driving the wafer to rotate and spraying an etching solution onto the substrate to wet the edge of the wafer further includes: blowing nitrogen gas onto the upper electrode layer.

[0015] According to some embodiments disclosed herein, blowing nitrogen gas onto the upper electrode layer further includes: the etching solution flowing from the edge of the wafer to the lower side of the upper electrode layer and flowing towards the center of the upper electrode layer on the lower side of the upper electrode layer, wherein the distance from the edge of the lower side of the upper electrode layer to the center is D, and D satisfies the relationship: 0≤D≤3mm.

[0016] According to some embodiments disclosed herein, the step of blowing nitrogen gas into the upper electrode layer further includes: setting the flow rate of the nitrogen gas as v, where v satisfies the relationship: 50L / min≤v≤150L / min.

[0017] Additional aspects and advantages of this disclosure will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this disclosure. Attached Figure Description

[0018] The above and / or additional aspects and advantages of this disclosure will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0019] Figure 1 is a partial schematic diagram of the gate tube in the manufacturing method of the gate tube according to an embodiment of the present disclosure;

[0020] Figure 2 is a partial schematic diagram of a gate tube in a method for manufacturing a gate tube according to some embodiments of the present disclosure;

[0021] Figure 3 is a partial schematic diagram of the gate tube in a method for manufacturing a gate tube according to some embodiments of the present disclosure;

[0022] Figure 4 is a partial schematic diagram of the gate tube in a method of manufacturing the gate tube according to some other embodiments of the present disclosure;

[0023] Figure 5 is a partial schematic diagram of the gate tube in the manufacturing method of the gate tube according to an embodiment of the present disclosure;

[0024] Figure 6 is a flowchart of a method for manufacturing a selector tube according to some embodiments of this disclosure;

[0025] Figure 7 is a flowchart of a method for manufacturing a selector tube according to some embodiments of this disclosure.

[0026] Figure label:

[0027] 100. Selector tube;

[0028] 1. Substrate; 2. Dielectric layer;

[0029] 3. Lower electrode layer; 4. First metal layer;

[0030] 5. Resistive switching layer; 6. Second metal layer; 7. Top electrode layer; 8. Wafer;

[0031] 9. Etching solution. Detailed Implementation

[0032] The embodiments of this disclosure are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. The embodiments of this disclosure are described in detail below.

[0033] The following figures, with reference to Figures 1-7, illustrate a method for manufacturing a selector tube 100 according to an embodiment of this disclosure.

[0034] Referring to Figures 1, 3, 4, 6, and 7, the manufacturing method of the selector tube 100 according to the embodiments of this disclosure mainly includes the following steps:

[0035] Prepare substrate 1, and deposit dielectric layer 2 on the upper side of substrate 1;

[0036] A lower electrode layer 3 is deposited on the upper side of the dielectric layer 2, and a first metal layer 4 is deposited on the upper side of the lower electrode layer 3.

[0037] A resistive switching layer 5 is deposited on the upper side of the first metal layer 4, and a second metal layer 6 is deposited on the resistive switching layer 5.

[0038] An upper electrode layer 7 is deposited on the second metal layer 6 to form a wafer 8;

[0039] Flip the wafer 8 so that the substrate 1 faces upward and the upper electrode layer 7 faces downward;

[0040] The wafer 8 is driven to rotate, and the etching solution 9 is sprayed onto the substrate 1 so that the etching solution 9 wets the edge of the wafer 8;

[0041] Simultaneously, wet etching is performed on the edges of the second metal layer 6, the resistive switching layer 5, the first metal layer 4, and the lower electrode layer 3.

[0042] Specifically, the selector 100 includes a wafer 8 structure comprising a substrate 1, a dielectric layer 2, a lower electrode layer 3, a first metal layer 4, a resistive switching layer 5, a second metal layer 6, and an upper electrode layer 7. During wafer 8 fabrication, the dielectric layer 2, the lower electrode layer 3, the first metal layer 4, the resistive switching layer 5, the second metal layer 6, and the upper electrode layer 7 are sequentially deposited on the substrate 1, and the edges of the wafer 8 are beveled.

[0043] Furthermore, the embodiments disclosed herein employ a wet etching process for the wafer edges. First, the wafer 8 is flipped so that the substrate 1 faces upwards, and the upper electrode layer 7 is located below the substrate 1. The wafer 8 is fixed on a stage, which can drive the wafer 8 to rotate. Then, an etching solution 9 is sprayed through a nozzle onto the side of the substrate 1 away from the upper electrode layer 7. The etching solution 9 flows along the diameter of the substrate 1 towards the edge of the wafer 8 to etch the edge of the wafer 8. According to Bernoulli's principle, the etching solution 9 flowing to the edge of the wafer 8 will wet towards the center of the upper electrode layer 7, thereby contacting the second metal layer 6, the resistive switching layer 5, the first metal layer 4, and the lower electrode layer 3 below the substrate 1, to perform wet etching on the second metal layer 6, the resistive switching layer 5, the first metal layer 4, and the lower electrode layer 3.

[0044] Compared to dry etching, wet etching has a faster rate, and the byproducts generated during wet etching are soluble, which can be used to clean and remove the byproducts from wafer 8. This avoids the problems of difficult-to-remove byproducts and metal agglomeration that occur in dry etching, thus solving the problem of metal exposure and contamination at the edges of wafer 8. This setup, by introducing wet etching, makes the etching of the second metal layer 6 and the first metal layer 4 in the manufacturing process of the selector 100 simpler and more convenient.

[0045] According to some embodiments disclosed herein, and in conjunction with FIG6, the step of simultaneously performing wet etching on the edges of the second metal layer 6, the resistive switching layer 5, the first metal layer 4 and the lower electrode layer 3 further includes simultaneously performing wet etching on the edges of the upper electrode layer 7.

[0046] Specifically, when the wafer 8 is flipped so that the upper electrode layer 7 is below the substrate 1, the etching solution 9 flows to the edge of the wafer 8 and wets the upper electrode layer 7 towards its center. At the same time, the etching solution 9 also comes into contact with the upper electrode layer 7, allowing for wet etching of the edge of the upper electrode layer 7 to remove defects at the edge of the wafer 8. This configuration allows for the unified wet etching of the upper electrode layer 7, the second metal layer 6, the resistive switching layer 5, the first metal layer 4, and the lower electrode layer 3, which is simple and efficient.

[0047] According to some other embodiments of this disclosure, in conjunction with FIG7, before the step of flipping the wafer 8 so that the substrate 1 faces upward and the upper electrode layer 7 faces downward, the method further includes: dry etching the edge of the upper electrode layer 7.

[0048] Specifically, the first metal layer 4 and the second metal layer 6 are the main areas prone to metal contamination during dry etching. Therefore, the upper electrode layer 7 can be dry-etched before flipping the wafer 8. After the upper electrode layer 7 is completely etched using dry etching, the second metal layer 6 can be exposed. This allows the etching solution 9 to flow to the exposed area of ​​the second metal layer 6 during wet etching, thus enabling wet etching of the second metal layer 6.

[0049] According to the embodiments disclosed herein, the material of the first metal layer 4 includes at least one of copper, palladium, silver, gold, and niobium, and the material of the second metal layer 6 includes at least one of copper, palladium, silver, gold, and niobium. This configuration forms the basic structure of the selector 100. If dry etching is used to remove defects in the second metal layer 6 and the first metal layer 4 at the edge of the wafer 8, at least one of the metals, copper, palladium, silver, gold, and niobium, will generate difficult-to-remove byproducts when exposed to plasma, leading to metal agglomeration and resulting in metal exposure and contamination at the edge of the wafer 8. In the embodiments disclosed herein, using etching solution 9 to etch the second metal layer 6 and the first metal layer 4 avoids the generation of difficult-to-remove byproducts and metal agglomeration during the etching process.

[0050] Referring to Figures 6 and 7, the step of driving the wafer 8 to rotate and spraying the etching solution 9 onto the substrate 1 to wet the edge of the wafer 8 further includes setting the rotational speed of the wafer 8 to n, where n satisfies the relationship: 200 RPM ≤ n ≤ 500 RPM. Specifically, after flipping the substrate 1, the substrate 1 is placed on the stage. If the stage rotational speed is set below 200 RPM, the wet etching effect will be affected. If the stage rotational speed is set above 500 RPM, the wafer 8 is easily thrown off. Therefore, setting the stage rotational speed between 200 RPM and 500 RPM can ensure the reliability of the stage driving the wafer 8 to rotate. The range that the etching solution 9 can wet in the direction from the edge of the wafer 8 towards the center of the upper electrode layer 7 is related to the rotational speed of the stage. In the embodiment disclosed in this paper, the lower the stage rotational speed, the lower the rotational speed of the wafer 8, and the more the etching solution 9 can etch in the direction from the edge of the wafer 8 towards the center of the upper electrode layer 7.

[0051] Referring to Figures 6 and 7, the step of driving the wafer 8 to rotate and spraying the etching solution 9 onto the substrate 1 to wet the edge of the wafer 8 further includes: setting the flow rate of the etching solution 9 to Q, where Q satisfies the relationship: Q ≥ 1 L / min. Specifically, according to Bernoulli's principle, the faster the fluid flow rate, the smaller the pressure in the transverse cross section of the fluid. In the embodiments disclosed herein, increasing the flow rate of the etching solution 9 can increase the amount of wetting of the etching solution 9 in the direction from the edge of the wafer 8 toward the center of the upper electrode layer 7, thus increasing the amount of etching of the edge of the wafer 8 toward the upper electrode layer 7. In the embodiments disclosed herein, the flow rate of the etching solution 9 is not less than 1 L / min, which ensures that the etching rate of the etching solution 9 on the edge of the wafer 8 meets the requirements for wet etching of edge defects of the wafer 8 in the embodiments disclosed herein.

[0052] Referring to Figures 6 and 7, the step of driving the wafer 8 to rotate and spraying etching solution 9 onto the substrate 1 to wet the edge of the wafer 8 further includes: the position of spraying etching solution 9 onto the substrate 1 is adjustable, and the distance between the position of spraying etching solution 9 onto the substrate 1 and the center of the substrate 1 is L, where L satisfies the relationship: 50mm ≤ L ≤ 100mm. Specifically, in this embodiment, etching solution 9 is sprayed onto the upper side of the substrate 1 through a nozzle, and the position of the nozzle can be adjusted to adjust the etching amount of etching solution 9 on the edge of the wafer 8 towards the center. The position of the nozzle can be moved from the center of the substrate 1 towards the edge of the substrate 1, and the position of the nozzle spraying etching solution 9 onto the substrate 1 also moves with the movement of the nozzle.

[0053] Furthermore, the distance between the nozzle spraying the etching solution 9 onto the substrate 1 and the center of the substrate 1 is set between 50 mm and 100 mm. As the nozzle moves from the center of the substrate 1 towards the edge, the closer the nozzle is to the edge of the substrate 1, the greater the amount of etching solution 9 can wet the edge of the wafer 8 towards the center; conversely, the closer the nozzle is to the center of the substrate 1, the less the amount of etching solution 9 can wet the edge of the wafer 8 towards the center. This configuration allows adjustment of the nozzle's position relative to the substrate 1, thereby adjusting the etching amount at the edge of the wafer 8 in the wet etching process to meet the requirements of the wet etching process for the wafer 8. In the embodiments disclosed herein, it is also possible to adjust the amount of etching to be absent from the edge of the wafer 8.

[0054] As shown in Figures 6 and 7, the steps of driving the wafer 8 to rotate and spraying the etching solution 9 onto the substrate 1 to wet the edge of the wafer 8 also include blowing nitrogen gas onto the upward electrode layer 7.

[0055] Specifically, in the embodiments disclosed herein, the wafer 8 is disposed on the upper side of the carrier. During the process of the carrier driving the wafer 8 to rotate, nitrogen gas is blown onto the upward electrode layer 7. This can reduce the pressure on the lower side of the wafer 8 and increase the pressure on the upper side of the wafer 8, thereby ensuring the positional stability of the wafer 8 on the carrier.

[0056] Referring to Figures 5-7, the step of blowing nitrogen onto the upper electrode layer 7 further includes: the etching solution 9 flowing from the edge of the wafer 8 to the lower side of the upper electrode layer 7, and flowing towards the center of the upper electrode layer 7 from the lower side of the upper electrode layer 7. The distance D from the lower edge of the upper electrode layer 7 to the center is D, where D satisfies the relationship: 0 ≤ D ≤ 3 mm. Specifically, by adjusting the wafer 8 rotation speed, the etching solution 9 flow rate, and the spray position of the etching solution 9, the distance from the lower edge of the upper electrode layer 7 to the center can be between 0 and 3 mm. When the distance from the lower edge of the upper electrode layer 7 to the center is 0, the etching solution 9 does not etch the second metal layer 6, resistive switching layer 5, first metal layer 4, and lower electrode layer 3 on the lower side of the substrate 1. Furthermore, if the distance from the lower edge of the upper electrode layer 7 to the center exceeds 3 mm, it will affect the structure of the upper electrode layer 7.

[0057] According to the embodiments disclosed herein, the step of blowing nitrogen gas onto the upper electrode layer 7 further includes setting the nitrogen gas flow rate as v, where v satisfies the relationship: 50 L / min ≤ v ≤ 150 L / min. Specifically, nitrogen gas and etching solution 9 flow on the upper and lower sides of the wafer 8, respectively, and nitrogen gas has an obstructive effect on the wetting of etching solution 9. If the nitrogen gas flow rate is set to exceed 150 L / min, the obstructive effect of nitrogen gas on the wetting of etching solution 9 will be too strong, making it difficult for etching solution 9 to flow from the lower edge of the upper electrode layer 7 to the center, and making it difficult to etch the edges of the second metal layer 6, resistive switching layer 5, first metal layer 4, and lower electrode layer 3. If the nitrogen gas flow rate is set to be lower than 50 L / min, the wafer 8 is very likely to be thrown off at high stage rotation speeds. Therefore, setting the nitrogen gas flow rate between 50 L / min and 150 L / min can not only maintain the positional reliability of the wafer 8 on the stage, but also ensure the etching effect of etching solution 9 on the edges of wafer 8.

[0058] In the description of this disclosure, it should be understood that the terms “center,” “longitudinal,” “lateral,” “length,” “width,” “thickness,” “upper,” “lower,” “front,” “rear,” “left,” “right,” “vertical,” “horizontal,” “top,” “bottom,” “inner,” “outer,” “clockwise,” “counterclockwise,” “circumferential,” “radial,” and “circumferential” indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this disclosure.

[0059] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example disclosed herein. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.

[0060] Although embodiments of the present disclosure have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present disclosure, the scope of which is defined by the claims and their equivalents.

Claims

1. A method for manufacturing a selector tube, characterized in that, include: Prepare a substrate (1) and deposit a dielectric layer (2) on the upper side of the substrate (1); A lower electrode layer (3) is deposited on the upper side of the dielectric layer (2), and a first metal layer (4) is deposited on the upper side of the lower electrode layer (3); A resistive switching layer (5) is deposited on the upper side of the first metal layer (4), and a second metal layer (6) is deposited on the resistive switching layer (5); An upper electrode layer (7) is deposited on the second metal layer (6) to form a wafer (8); The wafer (8) is flipped so that the substrate (1) faces upward and the upper electrode layer (7) faces downward; The wafer (8) is driven to rotate, and an etching solution (9) is sprayed onto the substrate (1) so that the etching solution (9) wets the edge of the wafer (8); Simultaneously, wet etching is performed on the edges of the second metal layer (6), the resistive switching layer (5), the first metal layer (4), and the lower electrode layer (3).

2. The method for manufacturing the selection tube according to claim 1, characterized in that, The step of simultaneously performing wet etching on the edges of the second metal layer (6), the resistive switching layer (5), the first metal layer (4), and the lower electrode layer (3) further includes: Simultaneously, wet etching is performed on the edge of the upper electrode layer (7).

3. The method for manufacturing the selection tube according to claim 1, characterized in that, The step of flipping the wafer (8) so that the substrate (1) faces upward and the upper electrode layer (7) faces downward further includes: Dry etching is performed on the edge of the upper electrode layer (7).

4. The method for manufacturing the selection tube according to claim 1, characterized in that, The material of the first metal layer (4) includes at least one of copper, palladium, silver, gold and niobium; The material of the second metal layer (6) includes at least one of copper, palladium, silver, gold and niobium.

5. The method for manufacturing the selection tube according to claim 1, characterized in that, The step of driving the wafer (8) to rotate and spraying etching solution (9) onto the substrate (1) to wet the edge of the wafer (8) further includes: The rotational speed of the wafer (8) is set to n, where n satisfies the relationship: 200RPM≤n≤500RPM.

6. The method for manufacturing the selection tube according to claim 1, characterized in that, The step of driving the wafer (8) to rotate and spraying etching solution (9) onto the substrate (1) to wet the edge of the wafer (8) further includes: The flow rate of the etching solution (9) is set to Q, and Q satisfies the relationship: Q≥1L / min.

7. The method for manufacturing the selection tube according to claim 1, characterized in that, The step of driving the wafer (8) to rotate and spraying etching solution (9) onto the substrate (1) to wet the edge of the wafer (8) further includes: The position of the etching solution (9) sprayed onto the substrate (1) is adjustable. The distance between the position of the etching solution (9) sprayed onto the substrate (1) and the center of the substrate (1) is L, and L satisfies the relationship: 50mm≤L≤100mm.

8. The method for manufacturing the selection tube according to claim 1, characterized in that, The step of driving the wafer (8) to rotate and spraying etching solution (9) onto the substrate (1) to wet the edge of the wafer (8) further includes: Nitrogen gas is blown into the upper electrode layer (7).

9. The method for manufacturing the selection tube according to claim 7, characterized in that, The process of blowing nitrogen gas into the upper electrode layer (7) further includes: The etching solution (9) flows from the edge of the wafer (8) to the lower side of the upper electrode layer (7) and flows toward the center of the upper electrode layer (7) on the lower side of the upper electrode layer (7). The distance from the edge of the upper electrode layer (7) to the center of the etching solution (9) is D, and D satisfies the relationship: 0≤D≤3mm.

10. The method for manufacturing the selection tube according to claim 8, characterized in that, The step of blowing nitrogen gas into the upper electrode layer (7) further includes: Let the flow rate of the nitrogen gas be v, and let v satisfy the relationship: 50L / min≤v≤150L / min.

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