TWI777288B - Plasma processing equipment and its gas baffle structure, plasma processing method - Google Patents

Abstract

The embodiment of the present invention discloses a plasma processing device, a gas baffle structure thereof, and a plasma processing method. The gas baffle structure includes a first substrate and a plurality of spacers disposed on the first surface of the first substrate. The first substrate and the plurality of spacers form a plurality of gas cavities. The plurality of gas cavities include a central cavity and at least one annular cavity surrounding the central cavity. At least one annular cavity includes at least two first gas cavities. Each of the first gas chambers corresponds to a first gas inlet passage respectively. Each first gas inlet channel is independently controlled, so that the flow rate of the first gas introduced into the first gas inlet channel corresponding to each first gas chamber is independently controlled, and then during the etching process, it can be based on the etching requirements of the wafer surface to be processed. and etching conditions, individually control the gas flow rate introduced into each first gas chamber in the annular cavity to adjust the etching rate at different positions at the same distance from the center of the wafer to be processed, and improve the distance between the surface of the wafer to be processed and the center of the same distance. Etching non-uniformity at different locations.

Description

Plasma processing equipment and its gas baffle structure, plasma processing method

The present invention relates to the technical field of plasma processing, in particular to a gas baffle structure, plasma processing equipment and plasma processing method.

With the continuous development of plasma processing technology, the plasma processing equipment applying this technology has been continuously improved. Several plasma processing equipments have been developed, such as Capacitively Coupled Plasma (CCP) processing equipment. , Inductively Coupled Plasma (ICP) processing equipment and Electron Cyclotron Resonance (ECR) processing equipment. However, during the etching process of the current plasma processing equipment, uneven etching often occurs at different positions at the same distance from the center of the wafer to be processed.

In order to solve the above technical problems, the embodiment of the present invention provides a gas baffle structure, so as to reduce the etching process of the plasma processing equipment, improve the etching uniformity of the wafer surface to be processed at different positions at the same distance from the center, and improve the etching uniformity of the wafer to be processed. Etching non-uniformity at different positions of the wafer surface at the same distance from its center.

In order to solve the above problems, the embodiments of the present invention provide the following technical solutions: A gas baffle structure for plasma processing equipment, comprising: A first substrate and a plurality of spacers disposed on the first surface of the first substrate, the first substrate and the plurality of spacers form a plurality of gas cavities, and the plurality of gas cavities include a central cavity and a surrounding at least one annular cavity of the central cavity, at least one annular cavity in the at least one annular cavity includes at least two first gas cavities; Wherein, the first substrate has at least two first gas inlet passages penetrating through the first substrate, the first gas inlet passages are in one-to-one correspondence with the first gas chambers, and the corresponding first gas The cavities are communicated with each other, the first gas inlet passage is used for introducing a first gas, and each of the first gas inlet passages is independently controlled.

Preferably, the at least one annular cavity includes a plurality of annular cavities, and the number of the first gas cavities included in different annular cavities is the same or different.

Preferably, if the number of first gas cavities included in different annular cavities is different, at least one annular cavity among the plurality of annular cavities includes one first gas cavity.

Preferably, if the number of the first gas cavities included in the different annular cavities is different, at least two annular cavities in the plurality of annular cavities include a plurality of first gas cavities, and the corresponding annular cavities are different from each other. The number of the plurality of first gas cavities is different.

Preferably, the first substrate further has at least two second gas inlet passages penetrating through the first substrate, and the second gas inlet passages are in one-to-one correspondence with the first gas chambers, and are corresponding to the first gas chambers. The first gas chambers are connected; wherein, the second gas inlet passage is used for introducing the second gas, and the first gas and the second gas have different compositions.

Preferably, the first gas inlet passage has at least one first gas inlet hole, and is communicated with its corresponding first gas cavity through the first gas inlet hole; The second gas inlet passage has at least one second gas inlet hole, and is communicated with its corresponding first gas cavity through the second gas inlet hole.

Preferably, the first air inlet passage has at least two first air inlet holes, the second air inlet passage has at least two second air inlet holes, and the first air inlet hole is connected to the second air inlet hole. The two air inlet holes are arranged at intervals along the annular direction of the annular cavity.

Preferably, the central cavity is a central gas cavity, the first substrate further has a first central gas inlet passage through the first substrate, the first central gas inlet passage and the central gas cavity are communicated with each other for introducing the first gas, and the first central gas inlet passage and the first gas inlet passage are independently controlled.

Preferably, the first substrate further has a second central gas inlet passage through the first substrate, the second central gas inlet passage is communicated with the central gas cavity, wherein the second central gas inlet The gas inlet passage is used for introducing the second gas, and the second central gas inlet passage and the second gas inlet passage are independently controlled.

Preferably, it also includes a second substrate located on the side of the spacer away from the first substrate, the second substrate has a plurality of first air outlets, and the first air outlets are corresponding to the gas. cavity is connected.

A plasma processing equipment, comprising: a cavity, the cavity has an opening; a gas baffle structure located at the opening of the cavity, the space formed by the gas baffle structure and the cavity is a reaction chamber of the plasma processing equipment, and the gas baffle structure is the above-mentioned gas baffle structure; A gas shower head located in the reaction chamber and below the gas baffle structure, the gas shower head is provided with a plurality of second gas outlets, and the second gas outlets are used to communicate the gas chamber and the gas chamber. the reaction chamber; and a base located in the reaction chamber and opposite to the gas shower head, the base is used for placing wafers; Wherein, the first gas introduced into the first gas inlet passage is used for processing the wafer.

Preferably, the plasma processing equipment further includes: and a first control element corresponding to the first gas inlet passage one-to-one, and the first control element is used to control the flow rate of gas entering the first gas chamber through the first gas inlet passage.

Preferably, if the first substrate further has at least two second gas inlet passages penetrating the first substrate, the plasma processing equipment further comprises: one-to-one correspondence with the second gas inlet passages. A second control element, the second control element is used for controlling the gas flow rate entering the first gas chamber through the second gas inlet passage.

A plasma processing method, wherein, applied to the above-mentioned plasma processing equipment, the plasma processing method comprises: placing the wafer to be processed on the base; Filling the first gas into each of the first gas inlet passages in the first substrate; and controlling the flow rate of gas introduced into each of the first gas inlet passages to control the etching rate of the first surface of the wafer; Wherein, the flow rate of the first gas introduced into each of the first gas chambers is different.

Preferably, if the first substrate further has at least two second gas inlet passages penetrating the first substrate, the plasma processing method further includes: filling the second gas into the second gas inlet passage in the first substrate; By controlling the gas flow in each of the second gas inlet passages, the etching rate of the first surface of the wafer is controlled.

Compared with the prior art, the above technical solution has the following advantages: In the gas baffle structure of the plasma processing apparatus provided by the embodiment of the present invention, at least one annular cavity in the at least one annular cavity includes at least two first gas cavities, and each of the first gas cavities corresponds to one first gas cavity respectively. An air inlet passage is provided, and each of the first air inlet passages is independently controlled, so that the flow rate of the first gas introduced into the first air inlet passage corresponding to each of the first gas chambers is independently controlled. Therefore, when applied to etching, based on the etching requirements and etching conditions of the surface of the wafer to be processed, the gas flow rate introduced into each of the first gas chambers in the annular cavity is individually controlled to adjust the distance from the center of the wafer to be processed. The etching rates at different positions at the same distance make the etching rates at different positions at the same distance from the center of the wafer surface to be processed more balanced, thereby improving the etching uniformity at different positions at the same distance from the center of the wafer surface to be processed , to improve the uneven etching of the surface of the wafer to be processed at the same distance from its center at different positions.

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those with ordinary knowledge in the technical field without making progressive changes shall fall within the protection scope of the present invention.

Many specific details are set forth in the following description to facilitate a full understanding of the present invention, but the present invention can also be implemented in other ways different from those described herein, and those with ordinary knowledge in the art can do so without departing from the connotation of the present invention. In the case of similar promotion, the present invention is not limited by the specific embodiments disclosed below.

As mentioned in the Background Art, during the etching process of the current plasma processing equipment, the problem of uneven etching often occurs at different positions at the same distance from the center of the wafer to be processed.

The study found that during the etching process, the uneven distribution of the radio frequency field of the plasma processing equipment or the uneven gas ejected from the exhaust hole of the shower head will cause uneven etching in the entire etching area during the etching process, such as , along the Y-axis or X-axis parallel to the base of the entire etching area, the etching rate of the middle etching area will be high, and the etching rate of the etching area on both sides will be low, that is, the etching rate curve is V-shaped, or the etching rate in the middle is low. The etching rate is high, that is, the etching rate curve is an inverted V-shaped, or, the etching rate in the middle and both sides is low, and the etching rate in the middle and the middle of the two sides is high, that is, the etching rate curve is M-type, or, the middle and both sides are The etching rate is high, and the etching rate between the middle and the two sides is low, that is, the etching rate curve is W-shaped.

In view of the above situations, the gas baffle structure is often divided into a central cavity and at least one annular cavity surrounding the central cavity, and each annular cavity can independently control the flow rate of the process gas introduced into it. Therefore, in the etching process, based on the etching requirements and etching conditions of the surface of the wafer to be processed, the gas flow rate of different annular cavities can be adjusted to adjust the etching rate at different distances from the center of the wafer to be processed along the same direction, Further, the etching uniformity of the surface of the wafer to be processed at different distances from the center along the same direction can be improved. However, this structure cannot solve the problem that uneven etching often occurs at different positions at the same distance from the center of the wafer to be processed.

In view of this, an embodiment of the present invention provides a gas baffle structure of a plasma processing apparatus, as shown in FIG. 1 , FIG. 2 and FIG. 3 , the gas baffle structure includes: The first substrate 100 and a plurality of spacers 200 disposed on the first surface of the first substrate 100, the first substrate 100 and the plurality of spacers 200 form a plurality of gas cavities 300, and the plurality of gas cavities 300 includes a central cavity 301 and at least one annular cavity 302 surrounding the central cavity 301, and at least one annular cavity 302 of the at least one annular cavity 302 includes at least two first gas cavities 3021; The first substrate 100 has at least two first gas inlet passages 400 penetrating through the first substrate 100 , the first gas inlet passages 400 correspond to the first gas chambers 3021 one-to-one, and the first gas inlet passages 400 A gas inlet passage 400 communicates with its corresponding first gas cavity 3021 , the first gas inlet passage 400 is used for introducing a first gas, and each of the first gas inlet passages 400 is controlled independently.

Preferably, in the embodiment of the present invention, the first gas cavities 3021 are distributed along the axial direction of the annular cavity 302 , that is, the distances between the first gas cavities 3021 and the central cavity 301 are the same.

On the basis of any of the above embodiments, in one embodiment of the present invention, the gas baffle structure is an aluminum alloy gas baffle structure, and in other embodiments of the present invention, the gas baffle structure is further The gas baffle structure of other materials can be used, which is not limited in the present invention, and depends on the specific situation.

It should be noted that, continuing as shown in FIG. 1 , a sealing ring 500 is further provided on the side of the spacer 200 away from the first substrate 100 to prevent gas leakage in each gas cavity 300 and affect the inside of each gas cavity 300 The content of the gas, which in turn affects the etch rate.

In the gas baffle structure of the plasma processing apparatus provided by the embodiment of the present invention, the gas baffle includes a plurality of gas cavities 300 , and the plurality of gas cavities 300 include a central cavity 301 and at least a plurality of gas cavities surrounding the central cavity 301 . An annular cavity 302, at least one annular cavity 302 in the at least one annular cavity 302 includes at least two first gas cavities 3021, each of the first gas cavities 3021 respectively corresponds to a first gas inlet passage 400, each of the first gas cavities 3021 An air inlet passage 400 is independently controlled, so that the flow rate of the first gas introduced into the first air inlet passage 400 corresponding to each of the first gas chambers 3021 is independently controlled. Therefore, during the etching process, the gas flow rate of each first gas cavity 3021 in the annular cavity 302 can be individually controlled based on the etching requirements and etching conditions of the surface of the wafer to be processed, so as to adjust the distance from the wafer to be processed. The etching rates at different positions at the same distance from the center of the circle make the etching rates at different positions at the same distance from the center of the wafer to be processed more balanced, thereby improving the etching rate at different positions at the same distance from the center of the wafer to be processed. Uniformity, improve the uneven etching of the wafer surface to be processed at the same distance from its center at different positions.

It should be noted that, in the embodiment of the present invention, the first gas is a process gas, and the type of the first gas is also different due to different etching objects. Specifically, in an embodiment of the present invention, the The first gas may be at least one or any combination of at least two of the fluorocarbon gases C _x F _y , Ar, N ₂ , O ₂ , H ₂ and CO ₂ , which is not limited in the present invention, and depends on the situation. Certainly.

It should also be noted that, in the embodiment of the present invention, the gas flow rate may be the mass flow rate of the gas or the volume flow rate of the gas, which is not limited in the present invention, and depends on the situation.

The following description takes the gas flow as the mass flow of the gas as an example.

On the basis of any of the above embodiments, in an embodiment of the present invention, the first gas inlet passage 400 has at least one first gas inlet hole 401 , through which the first gas inlet hole 401 and the first gas The cavity 3021 is communicated. It should be noted that, in order to improve the uniformity of the amount of the first gas introduced into the first gas chamber 3021 at different positions, on the basis of the above-mentioned embodiment, in an embodiment of the present invention, continue as shown in FIG. 2, the first gas inlet passage 400 has at least two first gas inlet holes 401, which are communicated with the first gas cavity 3021 through the first gas inlet holes 401. Preferably, the at least two gas inlet holes 401 communicate with the first gas cavity 3021. The first air inlet holes 401 are evenly distributed on the surface of the first air cavity 3021 . It should be noted that the present invention does not limit the number of the first air inlet holes 401 corresponding to the first gas cavity 3021. The more the number of the first air inlet holes 401 corresponding to the first gas cavity 3021 The more uniform the amount of the first gas at different positions in the first gas chamber 3021 is.

On the basis of any of the above embodiments, in an embodiment of the present invention, the first gas inlet passage 400 may be a straight gas inlet passage, that is, the gas conveying path of the first gas inlet passage 400 is a straight line ; In another embodiment of the present invention, the first gas inlet passage 400 can also be a bent gas inlet passage, that is, the gas conveying path in the first gas inlet passage 400 is non-linear, the present invention There is no restriction on this, and it depends on the situation.

It should be noted that, if the gas conveying path of the first gas inlet passage 400 is a straight line, the end of the first gas inlet passage 400 away from the first gas inlet hole 401 is located in the first gas cavity 3021 Just above the gas inlet passage 400; if the gas transport path in the first gas inlet passage 400 is non-linear (such as a curve or a broken line), the end of the first gas inlet passage 400 away from the first gas inlet hole 401 can be It is not located directly above the corresponding first gas cavity 3021, which is not limited in the present invention, as long as it is ensured that the first gas inlet passage 400 can pass the process gas into its corresponding first gas inlet hole 401. , depending on the situation.

On the basis of any of the above embodiments, in an embodiment of the present invention, the plurality of gas cavities 300 include a central cavity and 301 two annular cavities 302 surrounding the central cavity 301. The two annular cavities 301 At least one annular cavity 302 in 302 includes at least two first gas cavities 3021 .

In another embodiment of the present invention, the plurality of gas cavities 300 include a central cavity 301 and a plurality of annular cavities 302 surrounding the central cavity 301, and at least two annular cavities 302 of the plurality of annular cavities 302 include At least two first gas cavities 3021, preferably, in one embodiment, at least two annular cavities 302 of the plurality of annular cavities 302 include at least three first gas cavities 3021, so as to further improve the performance of the For the etching requirements and etching conditions of the round surface, the gas flow rate of each first gas chamber 3021 included in the same annular chamber 302 is individually controlled to adjust the etching rate at a plurality of different positions at the same distance from the center of the wafer to be processed. This makes the etching rate at the same distance from the center of the wafer to be processed more balanced at a plurality of different positions, and further improves the etching uniformity of the surface of the to-be-processed wafer at the same distance from its center.

It should be noted that, in the embodiment of the present invention, the projection of the central cavity 301 on the preset plane is a circle, and the projections of the plurality of annular cavities 302 surrounding the central cavity 301 on the preset plane form a ring The center of the projection of the central cavity 301 in the preset plane is the same as the center of the projection of the plurality of annular cavities 302 surrounding the central cavity 301 in the preset plane, wherein the The predetermined plane is parallel to the first surface of the first substrate 100 .

On the basis of any of the above embodiments, in an embodiment of the present invention, the at least one annular cavity 302 includes a plurality of annular cavities 302 , and the number of first gas cavities 3021 included in different annular cavities 302 is the same or different. It should be noted that, in an embodiment of the present invention, the different numbers of the first gas cavities 3021 included in the different annular cavities 302 include: the number of the first gas cavities 3021 included in the different annular cavities 302 The numbers are completely different. In another embodiment of the present invention, the different numbers of the first gas cavities 3021 included in the different annular cavities 302 include: the first gas cavities included in the different annular cavities 302 The number of 3021 is not exactly the same, which is not limited in the present invention, and depends on the specific situation.

It should also be noted that, in the embodiment of the present invention, the plurality of annular cavities 302 include at least two annular cavities 302 .

On the basis of any of the above embodiments, in an embodiment of the present invention, if the number of the first gas cavities 3021 included in different annular cavities 302 is different, at least one annular cavity in the plurality of annular cavities 302 302 includes a first gas chamber 3021 .

On the basis of any of the above embodiments, in an embodiment of the present invention, if the number of the first gas cavities 3021 included in the annular cavities 302 is different, at least two annular cavities 302 in the plurality of annular cavities 302 The cavity 302 includes a plurality of first gas cavities 3021, and the number of the plurality of first gas cavities 3021 corresponding to different annular cavities 302 is different, which is not limited in the present invention, and depends on the situation.

Specifically, as shown in FIG. 2 , in an embodiment of the present invention, the plurality of gas cavities include a central cavity 301 and two annular cavities 302 surrounding the central cavity 301 . The two annular cavities Only one annular cavity 302 in 302 includes a plurality of first gas cavities 3021 , and the annular cavity 302 includes four first gas cavities 3021 , and the other annular cavity 302 close to the central cavity 301 includes only one first gas cavity 3021 .

As shown in FIG. 4 , in another embodiment of the present invention, the plurality of gas cavities 300 include a central cavity 301 and three annular cavities 302 surrounding the central cavity 301 . There are two annular cavities 302 including a plurality of first gas cavities 3021 , and each annular cavity 302 of the two annular cavities 302 includes four first gas cavities 3021 .

As shown in FIG. 5 , in another embodiment of the present invention, the plurality of gas cavities 300 include a central cavity 301 and three annular cavities 302 surrounding the central cavity 301 . The three annular cavities 302 include a plurality of first gas cavities 3021 , and each annular cavity 302 of the two annular cavities 302 includes eight first gas cavities 3021 and one annular cavity 302 includes four first gas cavities 3021 .

On the basis of any of the above embodiments, in an embodiment of the present invention, each annular cavity 302 is evenly divided into a plurality of first gas cavities 3021, so as to individually control the different first gases in the region where each annular cavity 302 is located The flow rate of the gas introduced into the cavity 3021 is used to adjust the etching rate at a plurality of different positions at the same distance from the center of the wafer to be processed.

On the basis of any of the above embodiments, in an embodiment of the present invention, the widths of the plurality of annular cavities 302 are the same, that is, along the direction from the central cavity 301 to the annular cavity 302 , the widths of the annular cavities 302 are different. The dimensions are the same. In another embodiment of the present invention, the widths of the plurality of annular cavities 302 may not be exactly the same, which is not limited in the present invention, and depends on the specific situation.

On the basis of any of the above embodiments, in an embodiment of the present invention, as shown in FIG. 1 , FIG. 2 and FIG. 3 , the central cavity 301 is a central gas cavity, and the first substrate 100 There is also a first central gas inlet passage 600 penetrating the first substrate 100, the first central gas inlet passage 600 is communicated with the central gas cavity, and is used for introducing a first gas, and the first central gas inlet passage 600 is connected with the central gas cavity. The air inlet passage 600 and the first air inlet passage 400 are controlled independently. Preferably, in an embodiment of the present invention, the first central air inlet passage 600 has at least one first central air inlet hole 601, and It communicates with the central gas cavity through the first central gas inlet hole 601 . However, the present invention is not limited to this. In other embodiments of the present invention, the central cavity 301 may also include at least two central gas cavities, depending on the situation.

On the basis of any of the foregoing embodiments, in an embodiment of the present invention, as shown in FIG. 6 , FIG. 7 and FIG. 8 , the first substrate 100 further has at least two penetrating through the first substrate 100 . The second gas inlet passage 700, the second gas inlet passage 700 corresponds to the first gas cavity 3021 one-to-one, and the second gas inlet passage 700 is communicated with the corresponding first gas cavity 3021; in the present invention In the embodiment, the second gas inlet passage 700 is used to introduce a second gas, and the first gas and the second gas have different compositions. It should be noted that, in an embodiment of the present invention, the The different compositions of the first gas and the second gas include that the compositions of the first gas and the second gas are not exactly the same. In another embodiment of the present invention, the first gas and the second gas are not identical. Different compositions of the two gases include completely different compositions of the first gas and the second gas, which are not limited in the present invention, and depend on specific circumstances.

Preferably, in an embodiment of the present invention, the second gas is a regulating gas, and the regulating gas is used to regulate the etching rate of the first gas, for example, the second gas may be a fluorocarbon _{Gas CxFy} or _O2 . Specifically, in one embodiment of the present invention, the regulating gas is used to reduce the etching rate of the first gas, and in another embodiment of the present invention, the regulating gas is used to increase the first gas The etching rate is not limited in the present invention, and it depends on the specific situation.

On the basis of the above embodiment, in an embodiment of the present invention, the second gas inlet passages 700 corresponding to the first gas chambers 3021 are independently controlled, so as to flexibly control the passages of different first gas chambers 3021 The flow rate of the incoming second gas can be controlled, so as to better control the etching rate of the etching region corresponding to each first gas cavity 3021 and improve the uniformity of the etching region corresponding to each first gas cavity 3021 . In another embodiment of the present invention, the second gas inlet passages 700 corresponding to each of the first gas chambers 3021 may not be completely independently controlled, so that part of the second gas inlet passages 700 The flow rate of the second gas introduced into the gas inlet passage 700 is the same, and the flow rate of the second gas introduced into some of the second gas inlet passages 700 is different. In other embodiments of the present invention, the corresponding first gas chambers 3021 The second gas inlet passages 700 can also be controlled uniformly, so that the flow rates of the second gas introduced into each of the second gas inlet passages 700 are the same, which is not specifically limited in the present invention.

In a specific embodiment of the present invention, as shown in FIG. 7 , the first gas inlet passage 400 has at least one first gas inlet hole 401 and communicates with its corresponding first gas cavity 3021 through the first gas inlet hole 401 In the embodiment of the present invention, the second gas inlet passage 700 has at least one second gas inlet hole 701, and is communicated with its corresponding first gas cavity 3021 through the second gas inlet hole 701.

In another specific embodiment of the present invention, the first air inlet passage 400 has at least two first air inlet holes 401, and the second air inlet passage has at least two second air inlet holes 701. It should be noted that , in order to make the first gas and the second gas introduced into the first gas chamber 3021 evenly mixed, adjust the uniformity of etching at different positions in the first gas chamber 3021, specifically, the first gas chamber 3021 An air inlet hole 401 and the second air inlet hole 701 are arranged at intervals along the annular direction of the annular cavity 302 .

It should be noted that, in order to further make the first gas and the second gas introduced into the first gas chamber 3021 evenly mixed, on the basis of the above embodiment, in an embodiment of the present invention, The first air inlet holes 401 and the second air inlet holes 701 are arranged at intervals along the annular direction of the annular cavity 302 including: the first air inlet holes 401 and the second air inlet holes 701 are arranged along the annular cavity 302 The circular directions are evenly spaced.

On the basis of any of the above embodiments, in an embodiment of the present invention, the second gas inlet passage 700 may be a straight gas inlet passage, that is, the gas conveying path of the second gas inlet passage 700 is a straight line In another embodiment of the present invention, the second gas inlet passage 700 can also be a bent gas inlet passage, that is, the gas conveying path in the second gas inlet passage 700 is non-linear, the present invention There is no restriction on this, and it depends on the situation.

It should be noted that, if the gas conveying path of the second gas inlet passage 700 is a straight line, the end of the second gas inlet passage 700 away from the second gas inlet hole 701 is located at the corresponding first end of the gas inlet passage 700 . Right above the gas cavity 3021; if the gas conveying path in the second gas inlet passage 700 is non-linear (such as a curve or a broken line), the second gas inlet passage 700 is far away from the second gas inlet hole 701 One end of the gas inlet may not be located directly above the corresponding first gas cavity 3021, which is not limited in the present invention, as long as it is ensured that the second gas inlet passage 700 can pass the regulating gas into its corresponding second gas chamber 3021. The air inlet hole 701 is sufficient.

On the basis of any of the foregoing embodiments, in an embodiment of the present invention, if the central cavity 301 is a central gas cavity, the first substrate 100 further has a first substrate 100 extending through the first substrate 100 . Two central gas inlet passages (not shown), the second central gas inlet passage is communicated with the central gas cavity, wherein the second central gas inlet passage is used for introducing the second gas, and the The second central air inlet passage and the second air inlet passage 700 are independently controlled.

On the basis of any of the above embodiments, in an embodiment of the present invention, as shown in FIG. 9 , the gas baffle further includes a second spacer 200 on the side of the spacer 200 away from the first substrate 100 . The substrate 110, the second substrate 110 has a plurality of first air outlets 111, the plurality of first air outlets 111 communicate with the reaction chamber and the gas chamber 300, and the first gas chamber 3021 corresponds to the plurality of first air outlets 111 There are at least two first air outlets 111 in the first air outlet holes 111 .

As can be seen from the above, in the etching process of the gas baffle structure of the plasma processing equipment provided by any of the above embodiments of the present invention, based on the etching requirements and etching conditions of the surface of the wafer to be processed, the annular cavity 302 can be independently controlled. The gas flow rate passed into each first gas chamber 3021 to adjust the etching rate at the same distance from the center of the wafer to be processed at different positions, so that the surface of the to-be-processed wafer is at the same distance from the center of the etching at different positions. The rate is more balanced, thereby improving the etching uniformity at different positions of the same distance from the center of the wafer surface to be processed, and improving the unevenness of etching at different positions at the same distance from the center of the wafer surface to be processed.

Correspondingly, the present invention also provides a plasma processing equipment, as shown in FIG. 10 , the plasma processing equipment includes: cavity 1, the cavity 1 has an opening; The gas baffle structure 10 located at the opening of the cavity 1, the space formed by the gas baffle structure 10 and the cavity 1 is the reaction cavity of the plasma processing equipment; A gas shower head 20 located in the reaction chamber and below the gas baffle structure 10, the gas shower head 20 has a plurality of second air outlets, and the second air outlets are used to communicate with all the gas outlets. the gas chamber 300 and the reaction chamber; and a base 30 located in the reaction chamber and opposite to the gas shower head 20, the base 30 is used for placing wafers; The gas baffle structure 10 is the gas baffle structure 10 provided in any of the above embodiments, and the first gas introduced into the first gas inlet passage 400 is used for processing the wafer.

Preferably, in the embodiment of the present invention, the first gas cavities 3021 are distributed along the axial direction of the annular cavity 302 , that is, the distances between the first gas cavities 3021 and the central cavity 301 are the same.

Preferably, in an embodiment of the present invention, the flow rates of the first gas introduced into different first gas inlet passages 400 are different. Specifically, in an embodiment of the present invention, the different flow rates of the first gas introduced into the different first gas inlet passages 400 include: The flow rates of the first gas are not exactly the same. In another embodiment of the present invention, the different flow rates of the first gas introduced into the different first gas inlet passages 400 include: The flow rate of the first gas introduced into the gas inlet passage 400 is completely different, which is not limited in the present invention, and depends on the specific situation.

In the plasma processing apparatus provided by the embodiment of the present invention, the gas baffle structure 10 includes a central cavity 301 and at least one annular cavity 302 surrounding the central cavity 301 , and at least one annular cavity in the at least one annular cavity 302 302 includes at least two first gas cavities 3021, each of the first gas cavities 3021 corresponds to a first gas inlet passage 400, and each of the first gas inlet passages 400 is independently controlled, so that each of the first gas The flow rate of the first gas introduced into the first gas inlet passage 400 corresponding to the cavity 3021 is independently controlled, so that the first gas introduced into each of the first gas inlet passages 400 in the gas baffle structure 10 passes through the gas injection When the shower head 20 reaches different areas of the surface of the wafer to be processed, the plasma concentrations in different areas of the surface of the substrate to be processed can be independently controlled, so as to adjust the etching rates at different positions at the same distance from the center of the wafer to be processed, so that the The etching rate of the surface of the wafer to be processed at the same distance from its center at different positions is more balanced, thereby improving the etching uniformity of the surface of the to-be-processed wafer at the same distance from its center at different positions, improving the distance between the surface of the to-be-processed wafer and its center. Etching unevenness at different locations at the same distance.

On the basis of the above embodiment, in an embodiment of the present invention, the plasma processing apparatus further includes: a first control element 410 corresponding to the first gas inlet passage 400 one-to-one, the first control element 410 The element 410 is used to control the gas flow rate into the first gas chamber 3021 through the first gas inlet passage 400 .

On the basis of any of the above embodiments, in an embodiment of the present invention, if the first substrate 100 further has at least two second gas inlet passages 700 penetrating the first substrate 100; the plasma The body treatment device further includes: a second control element 710 corresponding to the second gas inlet passage 700 one-to-one, and the second control element 710 is used to control the entry of the first gas through the second gas inlet passage 700 Gas flow in cavity 3021.

On the basis of any of the above embodiments, in an embodiment of the present invention, if the first substrate 100 further has a first central gas inlet passage 600 passing through the first substrate 100, the plasma treatment The device further includes a first central control element 610 corresponding to the first central air inlet passage 600 , and the first central control element 610 is used to control the flow of gas entering the central gas chamber through the first central air inlet passage 600 . gas flow.

On the basis of any of the above embodiments, in an embodiment of the present invention, if the first substrate 100 further has a second central air inlet passage (not shown) passing through the first substrate 100, the The plasma processing apparatus further includes a second central control element (not shown) corresponding to the second central gas inlet passage, and the second central control element is used to control the entry of the gas through the second central gas inlet passage. the gas flow in the central gas chamber.

Correspondingly, the present invention also provides a plasma processing method, which is applied to the plasma processing equipment provided in any of the above embodiments. As shown in FIG. 11 , the plasma processing method includes: (S10) placing the wafer to be processed on the base 30; (S20) Filling each of the first gas inlet passages 400 in the first substrate 100 with a first gas; and (S30) controlling the gas flow rate introduced into each of the first gas inlet passages 400 to control the etching rate of the first surface of the wafer; The flow rate of the first gas introduced into each of the first gas chambers 3021 is different.

It should be noted that, in the embodiment of the present invention, the different flow rates of the first gas introduced into the first gas cavities 3021 include: The flow rates of the first gas are not exactly the same. In another embodiment of the present invention, the flow rates of the first gas introduced into the first gas chambers 3021 are different including: The flow rates of the first gas introduced into the first gas chamber 3021 are completely different.

In the plasma processing method provided by the embodiment of the present invention and applied to the plasma processing apparatus provided in any of the above embodiments, the gas baffle structure 10 includes a central cavity 301 and at least one annular cavity surrounding the central cavity 301 302. At least one annular cavity 302 in the at least one annular cavity 302 includes at least two first gas cavities 3021, each of the first gas cavities 3021 corresponds to a first gas inlet passage 400, and each of the first gas inlets 3021 corresponds to a first gas inlet passage 400. The passages 400 are independently controlled, so that when the first gas is filled into the first gas inlet passages 400 in the first substrate 100 , the first gas inlet passages 400 can be individually controlled to control the first gas inlet passages 400 . The gas flow rate introduced in the gas inlet passage 400 is to adjust the etching rate at the same distance and different positions from the center of the wafer to be processed, so that the etching rate at the same distance from the center of the to-be-processed wafer surface at different positions is relatively high. Balance, thereby improving the etching uniformity at different positions of the same distance from the center of the wafer surface to be processed, and improving the unevenness of etching at different positions at the same distance from the center of the wafer surface to be processed.

On the basis of any of the above embodiments, in an embodiment of the present invention, if the first substrate 100 further has at least two second gas inlet passages 700 penetrating the first substrate 100, the plasma Processing methods also include: filling the second gas into the second gas inlet passage 700 in the first substrate 100; and By controlling the gas flow in each of the second gas inlet passages 700, the etching rate of the first surface of the wafer is controlled.

Specifically, in an embodiment of the present invention, the etching rate corresponding to each first gas chamber 3021 can be adjusted by adjusting the flow ratio of the first gas and the second gas in the first gas chamber 3021 .

On the basis of any of the above embodiments, in an embodiment of the present invention, if the first substrate 100 further has a second central air inlet passage (not shown) passing through the first substrate 100, the The plasma treatment method also includes: filling the second gas into the second central gas inlet passage in the first substrate 100; The etching rate of the first surface of the wafer is controlled by controlling the gas flow rate of the second central gas inlet passage.

It should be noted that, in an embodiment of the present invention, each gas cavity 300 corresponds to an air inlet passage for introducing the first gas and a gas inlet passage for introducing the second gas, and the corresponding gas chambers 300 The gas inlet passage for introducing the first gas and the gas inlet passage for introducing the second gas are also independently controlled. Therefore, in other embodiments of the present invention, according to the etching situation, the etching rate corresponding to each gas chamber 300 can also be adjusted by adjusting the flow ratio of the first gas and the second gas in each gas chamber.

To sum up, in the plasma processing apparatus, the gas baffle structure, and the plasma processing method provided by the embodiments of the present invention, the gas baffle includes a plurality of gas cavities, and the plurality of gas cavities include a central cavity and a surrounding At least one annular cavity in the central cavity, at least one annular cavity in the at least one annular cavity includes at least two first gas cavities, each of the first gas cavities corresponds to a first gas inlet passage, and each of the first gas cavities corresponds to a first gas inlet passage. An air inlet passage is independently controlled, so that the flow rate of the first gas introduced into the first air inlet passage corresponding to each of the first gas chambers is independently controlled. Therefore, in the etching process, the gas flow rate of each first gas chamber in the annular cavity can be individually controlled based on the etching requirements and etching conditions on the surface of the wafer to be processed, so as to adjust the distance from the center of the wafer to be processed. The etching rates at different positions at the same distance make the etching rates at different positions at the same distance from the center of the wafer surface to be processed more balanced, thereby improving the etching uniformity at different positions at the same distance from the center of the wafer surface to be processed , to improve the uneven etching of the surface of the wafer to be processed at the same distance from its center at different positions.

Each part in this specification is described in a juxtaposed and progressive manner, and each part focuses on the differences from other parts, and the same and similar parts among the various parts can be referred to each other.

The above description of the disclosed embodiments enables any person of ordinary skill in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention . Thus, the present invention is not intended to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

1: Cavity 10: Gas baffle structure 100: The first substrate 110: Second substrate 111: The first vent 20: Gas shower head 200: Spacer 30: Abutment 300: gas chamber 301: Central cavity 302: annular cavity 3021: First gas chamber 400: The first air inlet passage 401: The first air inlet 410: First control element 500: sealing ring 600: The first central air inlet passage 601: The first center air inlet 610: First central control element 700: Second air inlet passage 701: Second air inlet 710: Second control element S10～S30: Steps

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or in the prior art, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. For those with ordinary knowledge in the technical field, other drawings can also be obtained from these drawings without making progressive changes. 1 is a schematic cross-sectional view of a gas baffle structure according to an embodiment of the present invention; 2 is a bottom view of a gas baffle structure provided by an embodiment of the present invention; 3 is a top view of a gas baffle structure according to an embodiment of the present invention; 4 is a diagram illustrating the division of each gas cavity in a gas baffle structure according to an embodiment of the present invention; 5 is a schematic diagram of the division of each gas cavity in another gas baffle structure provided by an embodiment of the present invention; 6 is a schematic cross-sectional view of another gas baffle structure provided by an embodiment of the present invention; 7 is a bottom view of another gas baffle structure provided by an embodiment of the present invention; 8 is a top view of another gas baffle structure provided by an embodiment of the present invention; 9 is a schematic cross-sectional view of yet another gas baffle structure provided by an embodiment of the present invention; 10 is a schematic cross-sectional view of a plasma processing apparatus according to an embodiment of the present invention; and FIG. 11 is a schematic flowchart of a plasma etching method according to an embodiment of the present invention.

301: Central cavity

302: annular cavity

3021: First gas chamber

401: The first air inlet

601: The first center air inlet

Claims (13)

A gas baffle structure for plasma processing equipment, comprising: a first substrate and a plurality of spacers disposed on a first surface of the first substrate, the first substrate and the plurality of spacers form a plurality of spacers Gas chambers, the plurality of gas chambers include a central chamber and at least one annular chamber surrounding the central chamber, at least one of the at least one annular chamber includes at least two first gas chambers, each of the first gas chambers Distributed along the axial direction of the annular cavity; wherein, the first substrate has at least two first gas inlet passages penetrating the first substrate, the first gas inlet passages are in one-to-one correspondence with the first gas cavity, and the The first gas inlet passage is communicated with the corresponding first gas cavity, and the first gas inlet passage is used for introducing a first gas, and each of the first gas inlet passages is controlled independently; It also has at least two second gas inlet passages penetrating the first substrate, the second gas inlet passages are in one-to-one correspondence with the first gas cavity, and the second gas inlet passages are communicated with their corresponding first gas chambers ; Wherein, the second gas inlet passage is used for introducing a second gas, and the composition of the first gas and the second gas is different; wherein, the first gas inlet passage has at least one first gas inlet hole, and passes through the The first gas inlet is communicated with the corresponding first gas cavity; the second gas inlet passage has at least one second gas inlet, and is communicated with the corresponding first gas cavity through the second gas inlet; wherein, the The first air inlet holes and the second air inlet holes are arranged at intervals along the annular direction of the annular cavity. The gas baffle structure according to claim 1, wherein the at least one annular cavity includes a plurality of annular cavities, and the number of the first gas cavities included in different annular cavities is the same or different. The gas baffle structure according to claim 2, wherein, if different in the annular cavity The number of the included first gas cavities is different, and at least one of the annular cavities among the plurality of annular cavities includes one of the first gas cavities. The gas baffle structure according to claim 2, wherein if the number of the first gas cavities included in the annular cavities is different, at least two of the annular cavities in the plurality of annular cavities include a plurality of the first gas cavities A gas cavity, and the number of the plurality of corresponding first gas cavities in different annular cavities is different. The gas baffle structure according to claim 1, wherein the first gas inlet passage has at least two first gas inlet holes, the second gas inlet passage has at least two second gas inlet holes, and the first gas inlet passage has at least two second gas inlet holes. The air holes and the second air inlet holes are arranged at intervals along the annular direction of the annular cavity. The gas baffle structure according to claim 1, wherein the central cavity is a central gas cavity, the first substrate further has a first central gas inlet passage through the first substrate, and the first central gas inlet The passage is communicated with the central gas cavity and is used for introducing the first gas, and the first central gas inlet passage and the first gas inlet passage are independently controlled. The gas baffle structure according to claim 6, wherein the first substrate further has a second central gas inlet passage penetrating the first substrate, and the second central gas inlet passage communicates with the central gas cavity, Wherein, the second central gas inlet passage is used for introducing a second gas, and the second central gas inlet passage and the second gas inlet passage are independently controlled. The gas baffle structure according to claim 1, wherein the gas baffle structure further comprises a second substrate located on a side of the spacer away from the first substrate, and the second substrate has a plurality of first outlets. A gas hole, the first gas outlet is communicated with the corresponding gas cavity. A plasma processing equipment, including: a cavity, the cavity has an opening; a gas baffle structure, which is located at the opening of the cavity, the space formed by the gas baffle structure and the cavity is A reaction chamber of the plasma processing equipment, the gas baffle structure is as follows The gas baffle structure described in any one of the items 1-8; a gas shower head, which is located in the reaction chamber and below the gas baffle structure, and the gas shower head has a plurality of second an air outlet, the second air outlet is used to communicate the gas chamber and the reaction chamber; and a base located in the reaction chamber and opposite to the gas shower head, and the base is used to place a wafer; Wherein, the first gas introduced into the first gas inlet passage is used for processing the wafer. The plasma processing apparatus according to claim 9, wherein the plasma processing apparatus further comprises: a first control element corresponding to the first gas inlet passage one-to-one, and the first control element is used to control the passage of the gas through the The gas flow rate of the first gas inlet passage into the first gas chamber. The plasma processing apparatus according to claim 11, wherein, if the first substrate further has at least two second gas inlet passages penetrating the first substrate, the plasma processing apparatus further comprises: A second control element corresponding to the gas passages one-to-one, and the second control element is used to control the gas flow rate entering the first gas chamber through the second gas inlet passage. A plasma processing method, which is applied to the plasma processing equipment according to any one of claims 9 to 11, the plasma processing method comprising: placing the wafer to be processed on the base; Each of the first gas inlet passages in the first substrate is filled with the first gas; and the flow rate of the gas introduced into each of the first gas inlet passages is controlled to control the etching rate of a first surface of the wafer; Wherein, the flow rate of the first gas introduced into each of the first gas chambers is different. The plasma treatment method according to claim 12, wherein if the first base The board also has at least two second gas inlet passages penetrating the first substrate, and the plasma processing method further comprises: filling the second gas inlet passages in the first substrate with a second gas; by controlling each of the second gas inlet passages The gas flow in the gas inlet channel controls the etching rate of the first surface of the wafer.

Images