CN116169052A - An etching device and its control method - Google Patents

Abstract

The invention discloses an etching device and a control method thereof, wherein the etching device comprises: the device comprises a cavity and a wafer basket positioned in the cavity, wherein a liquid inlet and a liquid outlet for conveying corrosive liquid are formed in the cavity; the bottom of the wafer basket is provided with a rotating device, wherein the rotating device drives wafers in the wafer basket to rotate when rotating, so that the contact uniformity of the wafers and the corrosive liquid is improved.

Description

An etching device and its control method

technical field

The invention relates to the technical field of semiconductors, in particular to an etching device and a control method thereof.

Background technique

The preparation of various semiconductor devices is inseparable from the etching process. The etching process is divided into dry etching and wet etching. Material. Wet etching is widely used in the preparation process of various devices due to its low cost, high selectivity ratio and large throughput.

Existing metal wet etching mostly adopts the immersion process, but due to the uneven flow of chemical liquid around the left and right sides and bottom of the wafer in the etching tank, the uniformity of the etched metal is very poor, and the complex micro The inhomogeneity of the metal film of the device directly affects the mechanical performance, electrical performance and yield of the device.

Contents of the invention

In view of the above problems, the present invention is proposed to provide an etching device and a control method thereof that overcome the above problems or at least partly solve the above problems.

In a first aspect, an etching device is provided, including:

A cavity and a wafer basket located in the cavity, the cavity is provided with a liquid inlet and a liquid discharge port for transporting corrosive liquid;

A rotating device is provided at the bottom of the wafer basket, wherein when the rotating device rotates, the wafers in the wafer basket are driven to rotate, so as to improve the contact uniformity between the wafers and the etching solution.

Optionally, the rotating device includes two rotating shafts to stably support the wafer.

Optionally, the rotation speed of the rotating device ranges from 0 to 50 r/min.

Optionally, the etching equipment further includes: a bubble generating device, the bubble generating device is located between the bottom of the cavity and the wafer basket.

Optionally, the air bubble generating device includes: an air inlet channel and an air outlet plate, and the air outlet plate is provided with a plurality of air outlet holes.

Optionally, the diameter of the air outlet is in the range of 0-5mm.

Optionally, the air bubble generating device includes: at least two air outlet plates, and the air outlet flow rate of each of the air outlet plates is independently controlled.

In a second aspect, there is provided a method for controlling an etching device, the etching device being the etching device described in any one of the first aspect, the method comprising:

moving the wafer into the wafer basket, and inputting the etching solution into the cavity;

The rotating device is turned on to drive the wafers in the wafer basket to rotate, so as to improve the contact uniformity between the wafers and the etching solution.

Optionally, the etching equipment further includes a bubble generating device, the bubble generating device is located between the bottom of the cavity and the wafer basket, and when moving the wafer into the wafer basket, And after inputting the etching solution into the cavity, it further includes: turning on the bubble generating device to stir the etching solution, so as to improve the contact uniformity between the wafer and the etching solution.

Optionally, the bubble generating device includes at least two air outlet plates, and the air outlet flow rate of each of the air outlet plates is independently controlled, and the opening of the air bubble generating device includes: opening the two air outlet plates in turn.

The technical solutions provided in the embodiments of the present invention have at least the following technical effects or advantages:

The etching equipment and its control method provided by the embodiments of the present invention, the setting of the etching equipment includes: a cavity and a wafer basket located in the cavity, and a rotating device is provided at the bottom of the wafer basket. In this way, when the rotating device rotates, the wafers in the wafer basket are driven to rotate, so that the contact uniformity between the wafers and the etching solution can be improved. Therefore, the mechanical performance, electrical performance and yield of the prepared device are guaranteed.

The above description is only an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention, it can be implemented according to the contents of the description, and in order to make the above and other purposes, features and advantages of the present invention more obvious and understandable , the specific embodiments of the present invention are enumerated below.

Description of drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiment. The drawings are only for the purpose of illustrating a preferred embodiment and are not to be considered as limiting the invention. Also throughout the drawings, the same reference numerals are used to designate the same components. In the attached picture:

Fig. 1 is the structural diagram of etching equipment in the embodiment of the present invention;

FIG. 2 is a flow chart of a method for controlling an etching device in an embodiment of the present invention.

Detailed ways

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided for more thorough understanding of the present disclosure, and to fully convey the scope of the present disclosure to those skilled in the art. Also, in the following description, descriptions of well-known structures and techniques are omitted to avoid unnecessarily obscuring the concepts of the present disclosure.

Various structural schematic diagrams according to embodiments of the present disclosure are shown in the accompanying drawings. The figures are not drawn to scale, with certain details exaggerated and possibly omitted for clarity of presentation. The shapes of the various regions and layers shown in the figure, as well as their relative sizes and positional relationships are only exemplary, and may deviate due to manufacturing tolerances or technical limitations in practice, and those skilled in the art will Regions/layers with different shapes, sizes, and relative positions can be additionally designed as needed.

In the context of the present disclosure, when a layer/element is referred to as being "on" another layer/element, the layer/element may be directly on the other layer/element, or there may be intervening layers/elements in between. element. Additionally, if a layer/element is "on" another layer/element in one orientation, the layer/element can be located "below" the other layer/element when the orientation is reversed.

Please refer to Fig. 1, the present invention provides a kind of etching equipment, comprising:

A cavity 1 and a wafer basket 2 located in the cavity 1, the cavity 1 is provided with a liquid inlet 11 and a liquid discharge 12 for transporting corrosive liquid;

The bottom of the wafer basket 2 is provided with a rotating device 3, wherein when the rotating device 3 rotates, the wafer 101 in the wafer basket 2 is driven to rotate, so as to improve the contact between the wafer 101 and the etching solution. contact uniformity.

It should be noted that the wafer patterning process often includes at least three steps: the first is an etching process, wherein the etching process is completed in an etching device. The second is the cleaning process, which is done in the cleaning equipment to wash away the attached corrosive liquid. The third is the drying process, which is completed in the drying equipment to dry the wafer to facilitate the next process. The etching equipment provided in the embodiment of the present application is used for an etching process, and may be used for immersion wet etching or spray wet etching, which is not limited here. It can be used for metal etching or etching of other materials, and there is no limitation here. In the subsequent description, the etching equipment is an immersion wet etching equipment as an example for illustration.

In the immersion process of wet etching, the Teflon wafer basket carrying the wafer to be etched is often immersed in an etching tank filled with a certain proportion of chemical etching solution. According to the required etching film thickness and etching Rate, set the time of the wafer in the etching solution, usually accompanied by mechanical agitation or shaking, after reaching the set etching time, then move it into ultra-pure deionized water to wash the residual reaction products and etching solution, and then dry the wafer to complete Metal graphics. Due to the uneven flow of chemical liquid around the left and right sides and bottom contact positions of the wafer and the wafer basket in the etching tank, the uniformity of the etched metal is very poor, and the unevenness of the metal film of complex micro-devices directly affects the mechanical properties of the device. System performance, electrical performance and yield.

In an optional embodiment, the cavity 1 is used to load the etching solution, and the wafer basket 2 is used to fix and install the wafers to be etched. The bottom of the wafer basket 2 is open, and the rotating device 3 can be installed between the bottom of the cavity 1 and the bottom opening of the wafer basket 2. When the wafer 101 is loaded in the wafer basket 2, the lower part of the wafer 101 just touches Rotating device 3, so that rotating device 3 can not only play the role of supporting wafer 101, but also drive wafer 101 to rotate when it is turned on, so that wafer 101 is fully and evenly contacted with the etching solution in cavity 1, thereby Ensure the uniformity of etching.

In an optional embodiment, the rotating device 3 may include two rotating shafts as shown in FIG. 1 to stably support the wafer 101 . Specifically, the axial directions of the two rotating shafts are perpendicular to the direction of the wafer surface placed in the wafer basket 2, and are arranged symmetrically with respect to the center of the wafer basket 2, so that when the rotating device 3 rotates, the wafer can be held The uniform rotation speed of 101 can also keep the wafer 101 stable. Of course, a single rotating shaft or more than two rotating shafts may also be provided, which is not limited here.

In an optional embodiment, the material of the rotating device 3 can also be set to be corrosion-resistant and wear-resistant materials, so as to prevent damage to it by corrosive liquid and ensure service life and reliability. It is also possible to set the rotational speed range of the rotating device 3 to be 0-50 r/min, so as to give consideration to both uniform contact and stability.

In the case that the etching equipment is an immersion wet etching equipment, it can be set to further include: a bubble generating device 4, the bubble generating device 4 is located between the bottom of the cavity 1 and the wafer basket 2 between. The bubbles generated by the bubble generating device 4 evenly stir the corrosion solution to ensure the complete coverage and uniform stirring of the surface of the wafer 101, eliminate the uneven flow of the chemical solution around the wafer, and realize the uniformity of etching. Wherein, the bubble generating device 4 may be a nitrogen gas bubble generating device, because the nitrogen gas is stable and not easy to react, and can avoid affecting the performance of the corrosive liquid.

As shown in FIG. 1 , the bubble generating device 4 includes: an air inlet channel 41 and an air outlet plate 42 , and the air outlet plate 42 is provided with a plurality of air outlet holes. The air intake passage 41 can be hollow tubular, and communicates with the air outlet plate 42, which is hollow plate-shaped, and a plurality of through holes are opened on the body of the air outlet plate 42 as air outlet holes. The air outlet holes have a diameter ranging from 0 to 5mm, and the air outlet holes are evenly distributed on the surface of the air outlet plate to ensure that the air bubbles can be densely and uniformly output into the corrosive liquid for stirring.

In an optional embodiment, the air bubble generating device 4 may include: at least two air outlet plates 42 , and the air outlet flow rate of each of the air outlet plates 42 is independently controlled. The air flow rate can be independently controlled by setting each air outlet plate 42 , and different stirring requirements can be achieved by setting different air outlet methods. For example, as shown in FIG. 1 , the air bubble generating device 4 can be set to include three gas outlet plates 42, which are respectively arranged in three positions on the left, middle, and right along the placement direction of the wafer, and the surfaces of the three gas outlet plates 42 are uniform. Small air bubble holes are distributed, and the nitrogen flow rate corresponding to the gas outlet plate 42 can be individually controlled and adjusted to ensure uniform stirring of a large number of small nitrogen air bubbles on the left, middle, and right sides of the wafer. In this way, during the etching process, combined with the rotation of the rotating device 3, the uniformly generated nitrogen bubbles provide complete coverage and uniform stirring of the wafer surface under the rotation of the wafer, eliminating the flow of chemical liquid around the wafer. Inhomogeneity, the uniformity of metal etching is achieved.

Specifically, the etching equipment provided by the embodiments of the present invention can provide more stable, controllable and repeatable etching, and the process is more reliable. And through the combination of the rotating device 3 and the bubble generating device 4, the uniformity of the corrosion liquid flow around the wafer during the etching process is improved, a more uniform metal film is obtained after etching, and the mechanical properties of the metal film are improved. The electrical performance has effectively improved the yield rate of device products.

Based on the same inventive concept, an embodiment of the present invention also provides a control method for the aforementioned etching equipment, the etching equipment is shown in Figure 1, and the control method is shown in Figure 2, including:

Step S201, moving the wafer 101 into the wafer basket 2, and inputting an etching solution into the cavity 1;

Step S202, turning on the rotating device 3 to drive the wafer 101 in the wafer basket 2 to rotate, so as to improve the contact uniformity between the wafer 101 and the etching solution.

Wherein, the corrosive liquid is input through the liquid inlet 11 on the cavity 1 , and the corrosive liquid is discharged from the cavity 1 through the liquid discharge port 12 after the etching is completed.

In an optional embodiment, the etching equipment further includes a bubble generating device 4, the bubble generating device 4 is located between the bottom of the cavity 1 and the wafer basket 2, and when the wafer 101 is placed on the wafer basket 2 In the round basket 2, after the etching solution is input into the cavity 1 to submerge the wafer 101, the bubble generating device 4 is turned on, the gas (such as nitrogen) is output from the inlet channel 41, and is output into the etching solution through the gas outlet plate 42, and stirred The etching solution is used to improve the contact uniformity between the wafer 101 and the etching solution.

In an optional embodiment, the air bubble generating device 4 can also be set to include at least two air outlet plates 42, and the air outlet flow rate of each of the air outlet plates 42 is independently controlled, and the opening of the air bubble generating device 4 includes: opening in turn The two air outlet plates 42 . When there are three air outlet plates 42 as shown in FIG. 1 , the three air outlet plates 42 can be turned on in turn to ensure that each area can be fully stirred and avoid the mutual influence of stirring in different areas.

Since the control method of the etching equipment introduced in the embodiment of the present invention is the control method of the etching equipment introduced in the embodiment of the present invention, its specific implementation has been explained in the process of introducing the etching equipment, so based on the embodiment of the present invention For the etching equipment introduced, those skilled in the art can understand the deformation of the control method of the etching equipment, so details will not be repeated here. All control methods for controlling the etching equipment in the embodiments of the present invention belong to the scope of protection of the present invention.

The technical solutions provided in the embodiments of the present invention have at least the following technical effects or advantages:

The etching equipment and its control method provided by the embodiments of the present invention, the setting of the etching equipment includes: a cavity and a wafer basket located in the cavity, and a rotating device is provided at the bottom of the wafer basket. In this way, when the rotating device rotates, the wafers in the wafer basket are driven to rotate, so that the contact uniformity between the wafers and the etching solution can be improved. Therefore, the mechanical performance, electrical performance and yield of the prepared device are guaranteed.

The algorithms and displays presented herein are not inherently related to any particular computer, virtual system, or other device. Various generic systems can also be used with the teachings based on this. The structure required to construct such a system is apparent from the above description. Furthermore, the present invention is not specific to any particular programming language. It should be understood that various programming languages can be used to implement the content of the present invention described herein, and the above description of specific languages is for disclosing the best mode of the present invention.

In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure the understanding of this description.

Similarly, it should be appreciated that in the foregoing description of exemplary embodiments of the invention, in order to streamline this disclosure and to facilitate an understanding of one or more of the various inventive aspects, various features of the invention are sometimes grouped together in a single embodiment, figure, or its description. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the claims following the Detailed Description are hereby expressly incorporated into this Detailed Description, with each claim standing on its own as a separate embodiment of this invention.

Those skilled in the art can understand that the modules in the device in the embodiment can be adaptively changed and arranged in one or more devices different from the embodiment. Modules or units or components in the embodiments may be combined into one module or unit or component, and furthermore may be divided into a plurality of sub-modules or sub-units or sub-assemblies. All features disclosed in this specification (including accompanying claims, abstract and drawings) and any method or method so disclosed may be used in any combination, except that at least some of such features and/or processes or units are mutually exclusive. All processes or units of equipment are combined. Each feature disclosed in this specification (including accompanying claims, abstract and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise.

Furthermore, those skilled in the art will appreciate that although some embodiments herein include some features included in other embodiments but not others, combinations of features from different embodiments are meant to be within the scope of the invention. And form different embodiments. For example, in the following claims, any of the claimed embodiments may be used in any combination.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention can be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In a unit claim enumerating several means, several of these means can be embodied by one and the same item of hardware. The use of the words first, second, and third, etc. does not indicate any order. These words can be interpreted as names.

Claims (10)

1. An etching apparatus, comprising:

the device comprises a cavity and a wafer basket positioned in the cavity, wherein a liquid inlet and a liquid outlet for conveying corrosive liquid are formed in the cavity;

the bottom of the wafer basket is provided with a rotating device, wherein the rotating device drives wafers in the wafer basket to rotate when rotating, so that the contact uniformity of the wafers and the corrosive liquid is improved.

2. The etching apparatus according to claim 1, wherein:

the rotating device comprises two rotating shafts so as to stably support the wafer.

3. The etching apparatus according to claim 1, wherein:

the rotating speed range of the rotating device is 0-50 r/min.

4. The etching apparatus according to claim 1, further comprising:

and the bubble generating device is positioned between the bottom of the cavity and the wafer basket.

5. The etching apparatus according to claim 4, wherein the bubble generating means comprises:

the device comprises an air inlet channel and an air outlet plate, wherein a plurality of air outlet holes are formed in the air outlet plate.

6. The etching apparatus according to claim 5, wherein:

the aperture range of the air outlet hole is 0-5 mm.

7. The etching apparatus according to claim 5, wherein the bubble generating means comprises:

and the air outlet flow of each air outlet plate is independently controlled.

8. A control method of an etching apparatus, characterized in that the etching apparatus is the etching apparatus according to any one of claims 1 to 7, the method comprising:

moving the wafer into the wafer basket, and inputting corrosive liquid into the cavity;

and starting the rotating device to drive the wafer in the wafer basket to rotate so as to improve the contact uniformity of the wafer and the corrosive liquid.

9. The control method of claim 8, wherein the etching apparatus further comprises a bubble generating device located between the bottom of the chamber and the wafer basket, and further comprising, after the moving the wafer into the wafer basket and inputting the etching solution into the chamber:

starting the bubble generating device, and stirring the etching solution to improve the contact uniformity of the wafer and the etching solution.

10. The control method according to claim 9, wherein the bubble generating means includes at least two gas outlet plates, the flow rate of the gas outlet of each of the gas outlet plates being independently controlled, and the turning on the bubble generating means includes:

and opening the two air outlet plates in turn.

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