CN219716803U - Gas nozzle assembly and plasma processing device - Google Patents

Abstract

The utility model discloses a gas nozzle assembly, which comprises a gas inlet pipe, a first insulating block, a metal flange, a second insulating block and a gas nozzle body, wherein the gas inlet pipe is connected with the first insulating block; the air inlet pipe penetrates through the first insulating block, the metal flange and the second insulating block and is fixedly connected with an air inlet distribution cavity in the gas nozzle main body; the gas nozzle body is used for conveying reaction gas into a vacuum reaction cavity in the plasma processing device; the structure of the gas nozzle body comprises a gas inlet distribution cavity, gas spraying holes and a gas channel which is arranged in the gas nozzle and is connected with the gas inlet distribution cavity and the gas spraying holes; the volume of the air inlet distribution cavity accounts for 12-18% of the air nozzle body; the gas channels include a first gas channel and a second gas channel; the first gas channel is arranged at the central position of the gas nozzle body and a plurality of positions which are circumferentially and uniformly distributed relative to the central position; the second gas passages are circumferentially distributed outside the first gas passages in the gas nozzle body.

Description

Gas nozzle assembly and plasma processing device

Technical Field

The utility model belongs to the technical field of semiconductor etching process equipment, and relates to a gas nozzle assembly and a plasma processing device.

Background

In the prior art, a plasma processing apparatus uses a gas delivery system to deliver a reactive gas into a vacuum reaction chamber of the plasma processing apparatus, and generates plasma through a radio frequency power source and a coil, thereby etching a wafer. As shown in fig. 1, the reaction gas enters the reaction chamber through the top opening at the top of the reaction chamber of the plasma processing apparatus. The nozzle 600 is installed at the top opening, and the reactant gas is directly introduced into the nozzle 600 through the flange 500 connected with the nozzle 600, and a plurality of through holes are formed at the bottom of the nozzle 600, and are circumferentially distributed at the bottom of the nozzle 600, and the reactant gas flows into the reaction chamber 100 through the plurality of through holes. The air hole of the nozzle 600 is vertically downward at 90 degrees, and the air spray is uneven; the larger size of the metal flange 500 affects the coil to generate plasma.

Along with the development of etching process, the critical dimension is gradually smaller, the requirement on the index of the etching rate of the wafer (i.e. the uniformity of the etching on the wafer) is higher and higher, and the acceptable range of the difference of the etching uniformity is from 1% to 2% to 0.5%, and even the requirement of less than 0.5% is needed at present.

Disclosure of Invention

In order to solve the problems of poor diffusion uniformity of process gas and poor uniformity of etching results in the prior art, the utility model aims to provide a gas nozzle assembly and a plasma processing device for improving plasma etching uniformity.

The utility model provides a gas nozzle assembly, which is structurally improved.

The gas nozzle assembly mainly comprises an air inlet pipe, a first insulating block, a metal flange, a second insulating block and a gas nozzle body; the air inlet pipe penetrates through the first insulating block, the metal flange and the second insulating block and is fixedly connected with an air inlet distribution cavity in the air nozzle main body; the diameter of the second insulating block is the same as that of the upper end of the gas nozzle body, and the second insulating block is connected with the upper end of the gas nozzle body through a thread structure; the gas nozzle comprises a gas nozzle body, and is characterized in that a transition block and a second sealing ring are arranged between the second insulating block and the gas nozzle body, the second sealing ring is used for increasing the tightness between the second insulating block and the gas nozzle body, and the transition block is used for reducing the size of the metal flange.

The gas nozzle body is used for conveying reaction gas into a vacuum reaction cavity in the plasma processing device; the structure of the gas nozzle body comprises a gas inlet distribution cavity, gas spraying holes and a gas channel which is arranged in the gas nozzle and is connected with the gas inlet distribution cavity and the gas spraying holes;

the volume of the air inlet distribution cavity accounts for 12-18%, preferably 15% of the volume of the gas nozzle body;

the gas channel connecting the gas inlet distribution cavity and the gas spraying holes is divided into a first gas channel and a second gas channel;

the first gas channels are arranged at the central position of the gas nozzle body and a plurality of positions which are circumferentially and uniformly distributed relative to the central position; the extending direction of the first gas channel is vertical to the central horizontal cross section of the lower part of the gas nozzle body; the flow section of the first gas channel is designed to be a two-section non-uniform section, a short section of the first gas channel is close to the gas inlet distribution cavity, the length is 8.5-11.5mm, the length is 10mm preferably, the other section is a long section of the first gas channel, the length is 18-26mm, the length is 22mm preferably, and the gas flow rate can be increased through the two-section design;

the second gas channels are circumferentially distributed outside the first gas channels in the gas nozzle body, and each second gas channel comprises a first channel section and a second channel section connected with the first channel section; the first channel section is vertical to the horizontal plane, the second channel section is arranged at an angle of 10-30 degrees (alpha in figure 3) to the vertical plane, preferably 15 degrees, and is vertical to the inclined wall surface arranged at the lower part of the gas nozzle body;

the flow section of the second gas channel is designed to be a two-section non-uniform section, one section close to the gas inlet distribution cavity is a first channel section, the length is 18-26mm, the length is preferably 22mm, the other section is a second channel section, the length is 10-14mm, the length is preferably 12mm, and the gas flow rate can be increased through the two-section design;

the first air injection holes connected with the first air channel are circumferentially and uniformly distributed in the horizontal cross section of the center of the lower part of the air nozzle body, and the second air injection holes connected with the second air channel are circumferentially and uniformly distributed in the inclined wall surface arranged on the lower part of the air nozzle body.

The side of the gas nozzle body is provided with an annular groove for placing a sealing ring, so that the tightness of the joint of the sealing ring and the insulating window is improved.

The metal flange is arranged at the upper end of the second insulating block and is in threaded compression connection with the second insulating block through the first insulating block, and the diameter of the metal flange is 13.5-18.5mm, preferably 16mm; a first sealing ring is further arranged between the second insulating block and the metal flange and used for improving the tightness between the second insulating block and the metal flange;

the smaller the diameter size of the metal flange is, the better the metal flange is, because the metal can influence the magnetic field of the coil and further influence the uniformity in the subsequent etching process.

The first insulating block is wrapped outside the metal flange and partially wraps the air inlet pipe; the metal flange is tightly pressed through the threads of the first insulating block.

The utility model also provides a plasma processing device which comprises a reaction cavity, an electrostatic chuck and a coil, wherein the electrostatic chuck and the coil are arranged in the reaction cavity, a gas nozzle assembly is arranged on an insulating window at the top of the reaction cavity, and the gas nozzle assembly adopts the gas nozzle assembly.

The beneficial effects of the utility model include:

1. the nozzle outlet angle is changed and the air hole density is increased to further improve the uniformity of the process gas diffusion, thereby further improving the uniformity of the plasma gas in the etching cavity.

2. The size of the metal flange above the nozzle assembly is reduced, so that the influence of the metal flange on the coil in the induction of the high-frequency alternating magnetic field is reduced, and the plasma etching uniformity is improved.

3. The utilization efficiency of the reaction gas is improved, and the edge deviation defect of the etching result is improved.

Drawings

In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the utility model, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic view showing a structure of a prior art plasma processing apparatus.

Fig. 2 is a schematic structural view of a plasma processing apparatus according to an embodiment of the present utility model.

Fig. 3 is a schematic structural view of a gas nozzle assembly according to the present utility model.

Fig. 4 is a schematic structural view of a gas nozzle body according to the present utility model.

In fig. 2-3, 1-gas nozzle body, 2-gas inlet distribution chamber, 3-first gas channel, 31-first gas channel short section, 32-first gas channel long section; 4-a second gas channel; 41-a first channel segment; 42-a second channel segment; the device comprises a first air injection hole, a second air injection hole, a 7-air inlet pipe, a first insulating block, a 9-metal flange, a second insulating block, a first sealing ring, a transition block, a second sealing ring, an annular groove, a reaction cavity, an electrostatic chuck, an insulating window and a coil, wherein the first sealing ring, the transition block, the second sealing ring, the annular groove, the reaction cavity, the electrostatic chuck, the insulating window and the coil are arranged in sequence.

Detailed Description

The utility model will be described in further detail with reference to the following specific examples and drawings. The procedures, conditions, experimental methods, etc. for carrying out the present utility model are common knowledge and common knowledge in the art, except for the following specific references, and the present utility model is not particularly limited.

Fig. 2 shows a plasma processing apparatus, which mainly comprises a reaction chamber 15, an electrostatic chuck 16, a radio frequency power source, an air pump, an insulating window 17, a coil 18, and the like. The equipment utilizes plasma to contain a large amount of charged particles, such as active particles of electrons, ions, excited atoms, molecules, free radicals and the like, and various physical and chemical reactions occur on the surface of a wafer to be processed, thereby completing the technical processes of etching and the like.

In this apparatus, a wafer to be processed is fixed on a susceptor by an electrostatic chuck 16, and an electrostatic electrode generates an electrostatic suction force to support the wafer. The radio frequency power supply applies bias radio frequency voltage to the base through the radio frequency matching network to control the bombardment direction of charged particles. An air pump is arranged below the vacuum cavity and is used for discharging reaction byproducts and maintaining a vacuum environment. The insulating window 17 is arranged at the top of the reaction cavity 15, the coil 18 is arranged on the insulating window 17, and a high-frequency alternating magnetic field is generated after the external radio-frequency power source is connected, so that the reaction gas is ionized to generate plasma.

FIG. 3 illustrates a gas nozzle assembly provided by the present utility model. In the structure as shown in the figure, a plurality of air holes are uniformly distributed in the same cross section in the circumferential direction, and the air holes are perpendicular to the side wall surface of the gas nozzle body 1. The arrangement of the plurality of air injection holes with the same number and the same aperture relative to the plurality of rows can obtain the best effect of circumferentially and uniformly distributing and injecting the air flow in the same cross section. The outermost row of jet holes increases the number of jet holes so as to increase the jet density, and meanwhile, the jet holes are deflected by an angle, so that the jet holes are matched with the cavity of the current equipment to improve the uniformity of process gas diffusion, and the uniformity of plasma gas in the etching cavity is further improved. The size of the metal flange 9 is reduced by excessively connecting the first insulating block 8 and the second insulating block 10, so that the influence of the metal flange 9 on the high-frequency alternating magnetic field generated by the coil 18 is reduced, the density of generated plasmas is increased, and the plasma etching uniformity is improved.

Example 1

In this embodiment, a gas nozzle body 1 is provided for delivering a reaction gas into a vacuum reaction chamber in a plasma processing apparatus, where the structure of the gas nozzle body 1 includes a gas inlet distribution chamber 2, gas injection holes, and a gas channel connecting the gas inlet distribution chamber and the gas injection holes, which are disposed inside the gas nozzle.

The volume of the air inlet distribution cavity 2 accounts for 15% of the gas nozzle body.

The gas channels comprise a first gas channel 3 and a second gas channel 4;

the first gas channel 3 is arranged at the central position of the gas nozzle body and a plurality of positions which are circumferentially and uniformly distributed relative to the central position; the extending direction of the first gas channel 3 is vertical to the central horizontal cross section of the lower part of the gas nozzle body; the flow section of the first gas channel 3 is designed to be a two-section non-uniform section, one section of the first gas channel, which is close to the air inlet distribution cavity 2, is 10mm in length, and the other section of the first gas channel is 22mm in length;

the second gas channels 4 are circumferentially distributed outside the first gas channel 3 in the gas nozzle body, and the second gas channels 4 comprise a first channel section 41 and a second channel section 42 connected with the first channel section 41; the first channel section 41 is vertical to the horizontal plane, the second channel section 42 is arranged at 15 degrees with the vertical plane and is vertical to the inclined wall surface arranged at the lower part of the gas nozzle body; the flow section of the second gas channel 4 is designed to be a two-section non-uniform section, one section of the second gas channel, which is close to the gas inlet distribution cavity 2, is 22mm in length, and the other section of the second gas channel is 12mm in length.

The first air injection holes 5 connected with the first air channel 3 are circumferentially and uniformly distributed in the lower center horizontal cross section of the air nozzle body, and the second air injection holes 6 connected with the second air channel 4 are circumferentially and uniformly distributed in the inclined wall surface arranged at the lower part of the air nozzle body.

The side of the gas nozzle body is also provided with an annular groove 14 for placing a third sealing ring, so that the tightness of the joint with the insulating window is improved.

Example 2

In this embodiment, a gas nozzle assembly is provided, which includes a gas inlet pipe 7, a first insulating block 8, a metal flange 9, a second insulating block 10, and the gas nozzle body 1 mentioned in embodiment 1.

The air inlet pipe 7 penetrates through the first insulating block 8, the metal flange 9 and the second insulating block 10 and is fixedly connected with the air inlet distribution cavity 2 in the air nozzle main body 1.

The diameter of the second insulating block 10 is the same as that of the upper end of the gas nozzle body 1, and the second insulating block is connected through a thread structure; a transition block 12 and a second sealing ring 13 are arranged between the second insulating block 10 and the gas nozzle body 1, the second sealing ring 13 is used for increasing the tightness between the second insulating block 10 and the gas nozzle body 1, and the transition block 12 is used for reducing the size of the metal flange 9.

The metal flange 9 is arranged at the upper end of the second insulating block 10 and is in threaded compression connection with the second insulating block 10 through the insulating block 8, and the diameter of the metal flange is 16mm; a first sealing ring 11 is further arranged between the second insulating block 10 and the metal flange 9, and is used for improving the tightness between the second insulating block 10 and the metal flange 9.

The first insulating block 8 is wrapped outside the metal flange 9 and partially wraps the air inlet pipe 7, and the metal flange 9 is tightly pressed through threads of the first insulating block 8.

Example 3

In this embodiment, a plasma processing apparatus is provided, which includes a reaction chamber 15, an electrostatic chuck 16 disposed in the reaction chamber, and a coil 18, where a gas nozzle assembly described in embodiment 1 is disposed on an insulating window 17 at the top of the reaction chamber 15. The plasma contains a large amount of charged particles, such as electrons, ions, excited atoms, molecules, free radicals and other active particles, and various physical and chemical reactions occur on the surface of the wafer to be processed, so that the etching and other technological processes are completed.

The wafer to be processed is held on the susceptor by an electrostatic chuck 16, and an electrostatic electrode generates an electrostatic suction force to support the wafer. The radio frequency power supply applies bias radio frequency voltage to the base through the radio frequency matching network to control the bombardment direction of charged particles. An air pump is arranged below the vacuum cavity and is used for discharging reaction byproducts and maintaining a vacuum environment. The insulating window 17 is arranged at the top of the reaction cavity 15, the coil 18 is arranged on the insulating window 17, and a high-frequency alternating magnetic field is generated after the external radio-frequency power source is connected, so that the reaction gas is ionized to generate plasma.

In the description of the present specification, the descriptions of the terms "one embodiment," "example," "specific example," and the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present utility model. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The terms "comprises," "comprising," "includes," "including," or "including" when used in connection with an embodiment of the present utility model, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The present description describes example embodiments with reference to idealized example cross-sectional and/or plan and/or perspective views. The term "and/or" includes any or all combinations of associated listed items. When an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element or intervening elements may also be present. Also, when an element is referred to as being "on" another element, it can be directly on the other element or intervening elements may also be present. In contrast, the term "directly" means without intermediate elements. Furthermore, although the terms first, second, third and the like may be used to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. Thus, an element that is referred to as a first element in some embodiments may be referred to as a second element in other embodiments without departing from the teachings of the present utility model. Like reference numerals or reference numerals designate like elements. Thus, there may be deviations in the illustrated shapes that result, for example, from manufacturing techniques and/or tolerances. Thus, the exemplary embodiments should not be construed as limited to the regions of the illustrated shapes but are to include deviations in shapes that result, for example, from manufacturing. Thus, the regions illustrated in the figures are schematic in nature and their shapes are not intended to illustrate the actual shape of a device region and are not intended to limit the scope of the exemplary embodiments.

The protection of the present utility model is not limited to the above embodiments. Variations and advantages that would occur to one skilled in the art are included in the utility model without departing from the spirit and scope of the inventive concept, and the scope of the utility model is defined by the appended claims.

Claims (9)

1. A gas nozzle assembly is characterized by comprising a gas inlet pipe (7), a first insulating block (8), a metal flange (9), a second insulating block (10) and a gas nozzle body (1); the air inlet pipe (7) passes through the first insulating block (8), the metal flange (9) and the second insulating block (10) and is fixedly connected with the air inlet distribution cavity (2) in the gas nozzle main body (1);

the gas nozzle body (1) is used for conveying reaction gas into a vacuum reaction cavity in the plasma processing device and comprises a gas inlet distribution cavity (2) arranged in the gas nozzle, gas spraying holes and a gas channel connected with the gas inlet distribution cavity (2) and the gas spraying holes;

the gas channels comprise a first gas channel (3) and a second gas channel (4);

the first gas channel (3) is arranged at the central position of the gas nozzle body (1) and a plurality of positions which are circumferentially and uniformly distributed relative to the central position; the extending direction of the first gas channel (3) is vertical to the central horizontal cross section of the lower part of the gas nozzle body (1);

the second gas channels (4) are circumferentially distributed outside the first gas channels (3) in the gas nozzle body (1), and the second gas channels (4) comprise first channel sections (41) and second channel sections (42) connected with the first channel sections (41); the first channel section (41) is vertical to the horizontal plane, and the second channel section (42) is vertical to an inclined wall surface arranged at the lower part of the gas nozzle body (1);

the first air injection holes (5) connected with the first air channel (3) are circumferentially and uniformly distributed in the center horizontal cross section of the lower part of the air nozzle body, and the second air injection holes (6) connected with the second air channel (4) are circumferentially and uniformly distributed in the inclined wall surface arranged at the lower part of the air nozzle body.

2. A gas nozzle assembly according to claim 1, characterized in that the diameter of the second insulating block (10) is the same as the diameter of the upper end of the gas nozzle body (1), connected by a screw structure; a transition block (12) and a second sealing ring (13) are arranged between the second insulating block (10) and the gas nozzle body (1), the second sealing ring (13) is used for increasing the tightness between the second insulating block (10) and the gas nozzle body (1), and the transition block (12) is used for reducing the size of the metal flange (9).

3. A gas nozzle assembly according to claim 1, wherein the metal flange (9) is mounted at the upper end of the second insulating block (10) and is in threaded compression connection with the second insulating block (10) through an insulating block (8), and the diameter of the metal flange is 13.5-18.5mm; and a first sealing ring (11) is further arranged between the second insulating block (10) and the metal flange (9) and used for improving the tightness between the second insulating block (10) and the metal flange (9).

4. A gas nozzle assembly according to claim 1, characterized in that the first insulating block (8) is wrapped outside the metal flange (9) and partly wrapped around the gas inlet pipe (7), the metal flange (9) being screwed tightly by the first insulating block (8).

5. A gas nozzle assembly according to claim 1, characterized in that the volume of the gas inlet distribution chamber (2) is 12-18% of the gas nozzle body.

6. A gas nozzle assembly according to claim 1, characterized in that the flow cross section of the first gas channel (3) is designed as a two-section non-uniform cross section, a short section (31) of the first gas channel being adjacent to the gas inlet distribution chamber (2) and having a length of 8.5-11.5mm; the other section is a long section (32) of the first gas channel, and the length is 18-26mm;

the flow section of the second gas channel (4) is designed to be a two-section non-uniform section, a first channel section (41) is arranged close to the air inlet distribution cavity (2), and the length of the first channel section is 18-26mm; the other section is a second channel section (42) with the length of 10-14mm.

7. A gas nozzle assembly according to claim 1, characterized in that the side of the gas nozzle body is provided with an annular groove (14) for placing a third sealing ring for increasing the tightness of the connection with the insulating window.

8. A gas nozzle assembly according to claim 1, wherein the second channel section (42) is arranged at an angle of 10-30 ° to the vertical plane.

9. A plasma processing apparatus comprising a reaction chamber (15), an electrostatic chuck (16) disposed in the reaction chamber, and a coil (18), wherein the gas nozzle assembly according to any one of claims 1-8 is disposed on an insulating window (17) at the top of the reaction chamber (15).