Atomizing nozzle for wet etching process and wet etching process method

Abstract

The embodiment of the present invention provides an atomizing nozzle and a wet etching process method for a wet etching process, which relates to the field of semiconductor technology, wherein the atomizing nozzle comprises: a filter body, a guide body, a cyclone body and an atomizing body are sequentially arranged from top to bottom in the nozzle housing, the filter body filters the solution; the guide body guides the filtered solution through the guide body cavity and then guides it out through the first hole; the cyclone body guides the solution guided out of the first hole through the second hole and forms a cyclone state; the diameter plane of the hemispherical shell of the atomizing body is vertically pressed against the lower end face of the cyclone body, so that the etching solution in the cyclone state guided out of the second hole flows into the hemispherical shell, and a liquid spray hole is arranged at the vertex of the hemispherical shell to spray the solution in a hollow cone-shaped mist. This solution solves the defects of the existing atomizing nozzles, such as high working pressure, large flow rate, large atomized particles, and small spray angle.

Description

Technical Field

[0001] The invention relates to the field of semiconductor technology, and in particular to an atomizing nozzle used in a wet etching process and a wet etching process method. Background Art

[0002] Wet etching is a very important process in the field of semiconductor wet process. In wet etching, the use of nozzles is particularly important. The wafer is placed in a cavity, and the etching solution is sprayed from the nozzle onto the surface of the wafer by moving the nozzle in different directions. The etching solution reacts chemically with the material to be etched on the surface of the wafer, and the unnecessary material is removed by etching, thereby forming a structure with the required specific pattern. In wet etching, one of the technical difficulties faced is that the existing atomizing nozzles have defects such as high working pressure, large flow rate, large atomized particles, small spray angle, and short service life. As a result, the etching effect produced by the chemical reaction of the liquid sprayed from the nozzle with the material to be etched on the wafer will have process differences, and this difference will directly affect the wafer yield. Summary of the invention

[0003] In view of this, an embodiment of the present invention provides an atomizing nozzle for a wet etching process to solve the technical problems of high working pressure, large flow rate, large atomized particles, and small spray angle in the wet etching nozzle in the prior art. The atomizing nozzle includes:

[0004] A nozzle housing 1, wherein the nozzle housing 1 is a cavity;

[0005] A filter body 2, the lower end of which is inserted into the upper end of the nozzle housing 1, a filter screen is provided inside the filter body 2, and the filter body 2 is used to filter the etching solution;

[0006] The guide body 3 is arranged in the nozzle housing 1. The guide body 3 is a cavity with an upper opening. The upper opening of the guide body 3 is connected to the filter screen at the lower end of the filter body 2. A plurality of first holes 303 are arranged on the side wall of the lower end of the guide body 3. The guide body 3 is used to guide the filtered etching solution through the cavity of the guide body 3 and then output it through the first holes 303.

[0007] A vortex body 4 is arranged in the nozzle housing 1, the vortex body 4 is a columnar structure, the upper end surface of the vortex body 4 is vertically pressed against the lower end surface of the guide body 3, a plurality of second holes 401 are arranged on the circumferential side wall of the columnar structure, the second holes 401 are inclined at a preset angle along a preset circumferential direction, the second holes 401 correspond to the first holes 303 one by one, and the vortex body 4 is used to guide the etching solution guided out of the first hole 303 through the second holes 401 and form a vortex state;

[0008] The atomizing body 5 is arranged in the nozzle housing 1, and the atomizing body 5 includes a hemispherical shell 501. The diameter plane of the hemispherical shell 501 is vertically pressed against the lower end surface of the cyclone body 4. The diameter of the hemispherical shell 501 is the same as the diameter of the lower end of the cyclone body 4, so that the cyclone state etching solution derived from the second hole 401 flows into the hemispherical shell 501. A spray hole 502 is arranged at the vertex of the hemispherical shell 501. The spray hole 502 is located at the opening of the lower end surface of the nozzle housing 1. The spray hole 502 is used to spray the etching solution in the hemispherical shell 501 in the form of a hollow cone.

[0009] The embodiment of the present invention also provides a wet etching process method based on any of the above-mentioned atomizing nozzles for wet etching process, so as to solve the technical problems of high working pressure, large flow rate, large atomized particles and small spray angle existing in the wet etching nozzle in the prior art. The wet etching process method comprises:

[0010] The wafer is placed on the fixture of the wet etching chamber, and the atomizing nozzle is first moved to the middle position of the wafer by the spray arm, and then the atomizing nozzle is moved to the right side of the wafer, while the fixture is rotating so that the spray range of the etching solution covers the entire wafer;

[0011] The etching solution was pressurized to a preset pressure while the temperature of the etching solution was kept constant at 25°C.

[0012] Compared with the prior art, the beneficial effects that can be achieved by at least one of the above technical solutions adopted in the embodiments of this specification include at least: it is proposed that a filter body 2, a guide body 3, a cyclone body 4 and an atomizer body 5 are arranged in sequence from top to bottom in the nozzle housing 1, the filter body 2 can filter the etching solution, which is beneficial to improving the accuracy of the etching solution, the guide body 3 guides the filtered etching solution through the cavity of the guide body 3 and then guides it out through the first hole 303 to reduce the flow rate of the etching solution and reduce the working pressure, and then the first hole is used to guide the etching solution through the plurality of second holes 401 obliquely arranged on the cyclone body 4. The etching solution guided out by 303 is guided out and forms a swirl state (or spiral shape), which further reduces the flow rate of the etching solution and lowers the working pressure. Finally, the etching solution in the swirl state flows into the hemispherical shell 501 of the atomizer 5. The etching solution in the swirl state in the hemispherical shell 501 is sprayed out in the form of a hollow cone mist through the spray hole 502, which is beneficial to reducing the atomized particles of the etching solution and increasing the spray angle, thereby solving the defects of the existing atomizing nozzles such as high working pressure, large flow rate, large atomized particles, and small spray angle, and is beneficial to improving the uniformity of wet etching. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0014] Figure 1 is a front cross-sectional view of an atomizing nozzle for a wet etching process provided by an embodiment of the present invention;

[0015] Figure 2 is a front view of an atomizing nozzle for a wet etching process provided by an embodiment of the present invention;

[0016] Figure 3 is a front view of the appearance of a body guide provided by an embodiment of the present invention;

[0017] Figure 4 is a front view of the appearance of a cyclone body provided by an embodiment of the present invention;

[0018] Figure 5 is a top view of the appearance of a cyclone body provided by an embodiment of the present invention;

[0019] Figure 6 is a front view of the appearance of an atomizer provided by an embodiment of the present invention;

[0020] Figure 7 is a schematic diagram of an atomization shape provided by an embodiment of the present invention;

[0021] Figure 8 is a cross-sectional view of a hollow cone-shaped atomization shape provided by an embodiment of the present invention;

[0022] Fig. 9 It is a flow chart of a wet etching process method based on an atomizing nozzle for wet etching process provided by an embodiment of the present invention.

[0023] Reference numerals in the figures:

[0024] 1. Nozzle housing; 2. Filter body; 3. Guide body; 4. Swirl body; 5. Atomizing body; 201. Protrusion; 301. First cavity section; 302. Second cavity section; 303. First hole; 401. Second hole; 501. Hemispherical housing; 502. Spray hole. DETAILED DESCRIPTION

[0025] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0026] The following describes the implementation methods of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the following embodiments and the features in the embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present application.

[0027] In an embodiment of the present invention, an atomizing nozzle for a wet etching process is provided, such as Figure 1 , 2 As shown, the atomizing nozzle for wet etching process includes:

[0028] A nozzle housing 1, wherein the nozzle housing 1 is a cavity;

[0029] A filter body 2, the lower end of which is inserted into the upper end of the nozzle housing 1, a filter screen is provided inside the filter body 2, and the filter body 2 is used to filter the etching solution;

[0030] The guide body 3 is arranged in the nozzle housing 1. The guide body 3 is a cavity with an upper opening. The upper opening of the guide body 3 is connected to the filter screen at the lower end of the filter body 2. A plurality of first holes 303 are arranged on the side wall of the lower end of the guide body 3. The guide body 3 is used to guide the filtered etching solution through the cavity of the guide body 3 and then output it through the first holes 303.

[0031] A vortex body 4 is arranged in the nozzle housing 1, the vortex body 4 is a columnar structure, the upper end surface of the vortex body 4 is vertically pressed against the lower end surface of the guide body 3, a plurality of second holes 401 are arranged on the circumferential side wall of the columnar structure, the second holes 401 are inclined at a preset angle along a preset circumferential direction, the second holes 401 correspond to the first holes 303 one by one, and the vortex body 4 is used to guide the etching solution guided out of the first hole 303 through the second holes 401 and form a vortex state;

[0032] The atomizing body 5 is arranged in the nozzle housing 1, and the atomizing body 5 includes a hemispherical shell 501. The diameter plane of the hemispherical shell 501 is vertically pressed against the lower end surface of the cyclone body 4. The diameter of the hemispherical shell 501 is the same as the diameter of the lower end of the cyclone body 4, so that the cyclone state etching solution derived from the second hole 401 flows into the hemispherical shell 501. A spray hole 502 is arranged at the vertex of the hemispherical shell 501. The spray hole 502 is located at the opening of the lower end surface of the nozzle housing 1. The spray hole 502 is used to spray the etching solution in the hemispherical shell 501 in the form of a hollow cone.

[0033] Depend on Figure 1 , Figure 2 As shown in the figure, in the embodiment of the present invention, it is proposed that a filter body 2, a guide body 3, a cyclone body 4 and an atomizer body 5 are sequentially arranged in the nozzle housing 1 from top to bottom. The filter body 2 can filter the etching solution, which is beneficial to improving the accuracy of the etching solution. The guide body 3 guides the filtered etching solution through the cavity of the guide body 3 and then guides it out through the first hole 303 to reduce the flow rate of the etching solution and reduce the working pressure. Then, the etching solution guided out of the first hole 303 is guided out through the plurality of second holes 401 obliquely arranged on the cyclone body 4 and forms an atomizer body 5. The etching solution in the swirl state (or spiral shape) is further reduced, and the flow rate of the etching solution and the working pressure are lowered. Finally, the etching solution in the swirl state flows into the hemispherical shell 501 of the atomizing body 5, and the etching solution in the swirl state in the hemispherical shell 501 is sprayed out in the form of a hollow cone mist through the spray hole 502, which is beneficial to reducing the atomized particles of the etching solution and increasing the spray angle, thereby solving the defects of the existing atomizing nozzles such as high working pressure, large flow rate, large atomized particles, and small spray angle, and is beneficial to improving the uniformity of wet etching.

[0034] In the specific implementation, in order to improve the accuracy of the etching solution, thereby reducing the atomized particles and achieving fine atomization, it is proposed that the accuracy of the filter is 0.2um and the material is PTFE.

[0035] When implementing it, Figure 1 As shown, a protrusion 201 is provided on the side wall of the lower end of the filter body 2 , and the protrusion 201 is snap-connected with the inner wall of the nozzle housing 1 .

[0036] In specific implementation, in order to reduce the flow rate of the etching solution, such as Figure 3 As shown, it is proposed that the guide body 3 includes:

[0037] The first cavity section 301 is a cavity with upper and lower ends opened, and the upper end opening of the first cavity section 301 is connected to the filter screen at the lower end of the filter body 2;

[0038] The second cavity segment 302 is a cavity with an opening at the upper end. The upper opening of the second cavity segment 302 is connected to the lower opening of the first cavity segment 301. A plurality of first holes 303 are arranged on the side wall of the lower end of the second cavity segment 302. The outer diameter of the second cavity segment 302 is the same as the inner diameter of the first cavity segment 301. The outer diameter of the first cavity segment 301 is the same as the inner diameter of the nozzle housing 1, so that a small gap is formed between the outer side of the side wall of the second cavity segment 302 and the inner side of the side wall of the nozzle housing 1, and the etching solution discharged from the plurality of first holes 303 flows into the second hole 401 through the gap.

[0039] In specific implementation, in order to further reduce the flow rate of the etching solution, such as Figure 3 As shown, a plurality of first holes 303 are evenly distributed around the side wall of the lower end of the second cavity section 302, and the diameter of the first holes 303 may be 1.5 mm. The number of first holes 303 may be determined according to specific requirements, for example, 6 first holes 303 are provided.

[0040] In a specific implementation, the guide body 3 can be inserted into the nozzle housing 1 by means of interference fit and vertically pressed.

[0041] When implementing it, Figure 3 As shown, the number of the first holes 303 and the second holes 401 are the same, and the positions of the first holes 303 and the second holes 401 correspond one to one, so that the etching solution derived from the first holes 303 can flow smoothly into the second holes 401.

[0042] In specific implementation, in order to further reduce the flow rate of the etching solution, such as Figure 1 , Figure 4 , Figure 5 As shown, a plurality of the second holes 401 are evenly distributed around the circumference of the circumferential side wall of the column structure, the second holes 401 are square holes, the hole width c may be 1 mm, and the preset angle a may be 60°. That is, the square-shaped second holes 401 are inclined 60° along the preset circumferential direction (left or right), that is, the lower end of the second hole 401 forms a 60° with the horizontal direction.

[0043] In specific implementation, the cyclone body 4 is a columnar structure. The specific shape of the column is not specifically limited in this application. It can be a cylindrical column structure or a Figure 4 , Figure 5 The cylindrical structure with a gradually changing diameter shown includes an upper half and a lower half, wherein the diameter of the upper half gradually increases and the diameter of the lower half gradually decreases.

[0044] During specific implementation, the cyclone body 4 is pressed and attached to the upper surface of the atomizing body 5 by the flow guide body 3 without any gap.

[0045] During specific implementation, the number of the second holes 401 can be determined according to specific requirements. For example, six second holes 401 are set.

[0046] In specific implementation, in order to improve the swirl state of the etching solution, so as to achieve fine atomization and increase the atomization angle, such as Figure 6 As shown, it is proposed that the inclination angle b formed by the concave surface of the hemispherical shell 501 can be 120°.

[0047] In a specific implementation, in order to further achieve fine atomization and increase the atomization angle, the diameter of the liquid spray hole 502 may be 0.2 mm. Figure 7 , Figure 8 As shown, the etching solution sprayed from the spray hole is in the shape of a hollow cone mist, that is, the spray sprayed from the spray hole 502 is in the shape of a hollow cone.

[0048] In a specific implementation, the nozzle housing 1 , the flow guide 3 , the swirling body 4 and the atomizing body 5 may all be made of PVDF.

[0049] The embodiment of the present invention also provides a wet etching process method based on any of the above-mentioned atomizing nozzles for wet etching process, such as Fig. 9 As shown, the wet etching process method includes the following steps:

[0050] Step S901: placing a wafer on a fixture of a wet etching chamber, first moving the atomizing nozzle to the middle of the wafer by means of a spray arm, and then moving the atomizing nozzle to the right side of the wafer, while the fixture is rotating so that the spray range of the etching solution covers the entire wafer;

[0051] Step S902: pressurize the etching solution to a preset pressure while keeping the temperature of the etching solution constant at 25°C.

[0052] In the specific implementation, in the process of determining the preset pressure, different pressures can be applied to the etching solution in step S902, and the pressurization values ​​are adjusted to 2bar, 2.2bar, 2.4bar, 2.6bar, 2.8bar, and 3bar; the uniformity of the wet etching process of the machine under different pressures is detected, and the pressurization parameter corresponding to the optimal uniformity is set as the final preset pressure.

[0053] The embodiment of the present invention achieves the following technical effects: it is proposed that a filter body 2, a guide body 3, a vortex body 4 and an atomizer body 5 are sequentially arranged in the nozzle housing 1 from top to bottom, the filter body 2 can filter the etching solution, which is beneficial to improving the accuracy of the etching solution, the guide body 3 guides the filtered etching solution through the cavity of the guide body 3 and then guides it out through the first hole 303 to reduce the flow rate of the etching solution and reduce the working pressure, and then the etching solution guided out of the first hole 303 is guided out and discharged through the plurality of second holes 401 obliquely arranged on the vortex body 4. The formation of a swirl state (or spiral shape) further reduces the flow rate of the etching solution and lowers the working pressure. Finally, the etching solution in the swirl state flows into the hemispherical shell 501 of the atomizer 5. The etching solution in the swirl state in the hemispherical shell 501 is sprayed out in the form of a hollow cone through the spray hole 502, which is beneficial to reducing the atomized particles of the etching solution and increasing the spray angle, thereby solving the defects of the existing atomizing nozzles such as high working pressure, large flow rate, large atomized particles, and small spray angle, and is beneficial to improving the uniformity of wet etching.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the embodiments of the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An atomizing nozzle for wet etching process, characterized in that: include: A nozzle housing (1), wherein the nozzle housing (1) is a cavity; A filter body (2), the lower end of the filter body (2) being inserted into the upper end of the nozzle housing (1), a filter screen being arranged inside the filter body (2), and the filter body (2) being used to filter the etching solution; a body guide (3) disposed in the nozzle housing (1); the body guide (3) is a cavity with an upper opening, the upper opening of the body guide (3) is connected to the filter screen at the lower end of the filter body (2), a plurality of first holes (303) are disposed on the side wall at the lower end of the body guide (3), and the body guide (3) is used to guide the filtered etching solution through the cavity of the body guide (3) and then out through the first holes (303); a swirling body (4) disposed in the nozzle housing (1), the swirling body (4) being a columnar structure, the upper end surface of the swirling body (4) being vertically pressed against the lower end surface of the guide body (3), a plurality of second holes (401) being disposed on the circumferential side wall of the columnar structure, the second holes (401) being inclined at a preset angle along a preset circumferential direction, the second holes (401) corresponding one-to-one to the first holes (303), the swirling body (4) being used to guide the etching solution guided out of the first holes (303) through the second holes (401) and forming a swirling state; An atomizing body (5) is arranged in the nozzle housing (1), the atomizing body (5) comprising a hemispherical housing (501), the diameter plane of the hemispherical housing (501) being vertically pressed against the lower end surface of the cyclone body (4), the diameter of the hemispherical housing (501) being the same as the diameter of the lower end of the cyclone body (4), so that the cyclone state etching solution guided out of the second hole (401) flows into the hemispherical housing (501), a liquid spraying hole (502) is arranged at the vertex of the hemispherical housing (501), the liquid spraying hole (502) being located at the opening of the lower end surface of the nozzle housing (1), and the liquid spraying hole (502) being used to spray the etching solution in the hemispherical housing (501) in the form of a hollow cone-shaped mist.

2. The atomizing nozzle for wet etching process according to claim 1, characterized in that: The body guide (3) comprises: The first cavity section (301) is a cavity with upper and lower ends opened, the upper end opening of the first cavity section (301) being connected to the filter screen at the lower end of the filter body (2); The second cavity segment (302) is a cavity with an upper opening, the upper opening of the second cavity segment (302) butting up with the lower opening of the first cavity segment (301), a plurality of the first holes (303) being arranged on the side wall of the lower end of the second cavity segment (302), the outer diameter of the second cavity segment (302) being smaller than the outer diameter of the first cavity segment (301), the inner diameter of the second cavity segment (302) being the same as the inner diameter of the first cavity segment (301), and the outer diameter of the first cavity segment (301) being the same as the inner diameter of the nozzle housing (1).

3. The atomizing nozzle for wet etching process according to claim 2, characterized in that: A plurality of the first holes (303) are evenly distributed around the circumference on the side wall of the lower end of the second cavity section (302), and the diameter of the first holes (303) is 1.5 mm.

4. The atomizing nozzle for wet etching process according to any one of claims 1 to 3, characterized in that: A plurality of the second holes (401) are evenly distributed around the circumference of the circumferential side wall of the column structure; the second holes (401) are square holes with a hole width of 1 mm and a preset angle of 60°.

5. The atomizing nozzle for wet etching process according to any one of claims 1 to 3, characterized in that: The inclination angle formed by the concave surface of the hemispherical shell (501) is 120°.

6. The atomizing nozzle for wet etching process according to any one of claims 1 to 3, characterized in that: The diameter of the liquid spray hole (502) is 0.2 mm.

7. The atomizing nozzle for wet etching process according to any one of claims 1 to 3, characterized in that: The filter has an accuracy of 0.2um and is made of PTFE.

8. The atomizing nozzle for wet etching process according to any one of claims 1 to 3, characterized in that: The nozzle housing (1), the flow guide (3), the swirling body (4) and the atomizing body (5) are all made of PVDF.

9. The atomizing nozzle for wet etching process according to any one of claims 1 to 3, characterized in that: A protrusion (201) is provided on the side wall of the lower end of the filter body (2), and is snap-connected to the inner wall of the nozzle housing (1) via the protrusion (201).

10. A wet etching process method based on the atomizing nozzle for wet etching process according to any one of claims 1 to 9, characterized in that: include: The wafer is placed on the fixture of the wet etching chamber, and the atomizing nozzle is first moved to the middle position of the wafer by the spray arm, and then the atomizing nozzle is moved to the right side of the wafer, while the fixture is rotating so that the spray range of the etching solution covers the entire wafer; The etching solution was pressurized to a preset pressure while the temperature of the etching solution was kept constant at 25°C.

Images