Upper electrode assembly, process chamber and semiconductor processing equipment

Abstract

The present application discloses an upper electrode assembly, a process chamber and a semiconductor processing equipment, wherein the upper electrode assembly includes a conductive connecting tube and a uniform gas disk connected to the bottom end of the conductive connecting tube; a central air inlet channel and multiple edge air inlet channels are provided in the conductive connecting tube; the uniform gas disk includes a central air vent, an annular air inlet channel arranged around the central air vent, an annular air outlet channel arranged around the annular air inlet channel, and multiple connecting channels connecting the annular air inlet channels and the annular air outlet channels; the central air inlet channel is connected to the central air vent; and the edge air inlet channel is connected to the annular air inlet channel. In the present application, the process gas enters the uniform gas disk from the annular air inlet channel along the edge air inlet channel, and then passes through the connecting channel and the annular air outlet channel in sequence, and finally reaches the edge area of ​​the wafer. Since the gas distribution effect of the process gas mapped on the edge surface of the wafer is an annular band distribution and is uniformly distributed, the uniformity of wafer edge etching can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of semiconductor manufacturing equipment, and in particular to an upper electrode assembly, a process chamber, and semiconductor processing equipment. Background Art

[0002] A schematic diagram of the structure of an existing upper electrode assembly is shown in FIG. Figure 1 As shown, it includes a bracket 10A, and a grounded metal plate 20A and an upper dielectric plate 30A connected in sequence below the bracket 10A. A central air inlet channel 11A and multiple edge air inlet channels 12A are provided on the bracket 10A and the grounded metal plate 20A. During operation, the wafer 101A is located below the upper dielectric plate 30A, and the process gas reaches the edge of the wafer 101A through the edge air inlet channel 12A. Under the action of the electric field, plasma gas is formed to etch the edge of the wafer 101A.

[0003] The upper electrode assembly, see Figure 2 , Figure 2 It is a schematic diagram of the structure of the existing grounded metal plate when viewed from above. The outlet (small hole) 121A of the edge air inlet channel 12A is evenly distributed on the lower surface of the grounded metal plate 20A. The distribution effect of the process gas finally mapped on the edge surface of the wafer 101A is a circular point distribution, which is uneven and ultimately affects the uniformity of the edge etching of the wafer 101A. Summary of the Invention

[0004] In response to the above technical problems, the present application provides an upper electrode assembly, a process chamber and a semiconductor processing equipment, which can improve the problem of uneven etching caused by uneven distribution of process gas when it passes through the existing upper electrode assembly and reaches the edge area of ​​the wafer.

[0005] To solve the above technical problems, in a first aspect, an embodiment of the present application provides an upper electrode assembly for use in a process chamber of a semiconductor processing device, comprising a conductive connecting tube and a gas distribution plate connected to the bottom end of the conductive connecting tube;

[0006] A central air inlet channel and a plurality of edge air inlet channels are provided in the conductive connecting tube;

[0007] The air distribution plate includes a central air vent, an annular air inlet channel arranged around the central air vent, an annular air outlet channel arranged around the annular air inlet channel, and a plurality of connecting channels connecting the annular air inlet channel and the annular air outlet channel;

[0008] The central air inlet channel is in communication with the central air vent, and the central air vent is used to guide the gas flowing into the central air inlet channel to the central area of ​​the wafer;

[0009] The edge air inlet channel is communicated with the annular air inlet channel, and the annular air outlet channel is used to guide the gas flowing into the edge air inlet channel to the edge area of ​​the wafer.

[0010] Optionally, an annular constriction is provided in an area near the bottom of the annular air outlet channel.

[0011] Optionally, the aeration disk includes:

[0012] annular base plate;

[0013] A circular bottom plate is arranged on the inner ring of the annular bottom plate, and a first gap is provided between the circumferential end surface of the circular bottom plate and the inner side surface of the annular bottom plate; a first annular groove and a plurality of connecting grooves are provided on the top surface of the circular bottom plate, one end of the connecting groove is connected with the first annular groove, and the other end extends to the edge of the circular bottom plate and is connected with the first gap; a first annular protrusion is provided in the area near the bottom of the circumferential end surface of the circular bottom plate, and a second annular protrusion is provided on the inner side surface of the annular bottom plate, and the first annular protrusion is opposite to the second annular protrusion to form the annular necking in the annular air outlet channel.

[0014] A top plate is arranged on the top surfaces of the circular bottom plate and the annular bottom plate, covers the first annular groove to form the annular air inlet channel, covers the connecting groove to form the connecting channel, and covers the top surface of the first gap to form the annular air outlet channel.

[0015] Optionally, the inner side surface of the annular bottom plate includes, from top to bottom: a first vertical surface, a first inclined surface bent from the first vertical surface toward the circumferential end surface of the circular bottom plate, and a second vertical surface connected to the first inclined surface, and the second annular protrusion is formed by the first inclined surface and the second vertical surface;

[0016] The circumferential end surface of the circular base plate includes, from top to bottom, a third vertical surface, a second inclined surface bent from the third vertical surface toward the annular base plate, and a third inclined surface bent from the second inclined surface toward a direction away from the annular base plate, and the first annular protrusion is formed by the second inclined surface and the third inclined surface.

[0017] Optionally, the top surface of the circular bottom plate is further provided with a second annular groove surrounding the outer side of the first annular groove;

[0018] The plurality of connection grooves include a plurality of first sub-connection grooves and a plurality of second sub-connection grooves;

[0019] One end of the first sub-connecting groove is connected to the first annular groove, and the other end is connected to the second annular groove;

[0020] One end of the second sub-connecting groove is connected to the second annular groove, and the other end is connected to the first gap;

[0021] The top plate covers the second annular groove to form a buffer channel.

[0022] Optionally, the top plate includes:

[0023] A lower top plate is provided on the top surfaces of the circular bottom plate and the annular bottom plate; the top surface of the lower top plate is provided with a coolant groove;

[0024] The upper top plate is arranged on the top surface of the lower top plate and covers the coolant groove to form a coolant channel.

[0025] Optionally, the upper electrode assembly further includes:

[0026] A medium window is provided on the bottom surface of the gas uniforming disk;

[0027] An upper electrode isolation ring is provided on the bottom surface of the gas uniforming disk and sleeved on the outer side of the dielectric window;

[0028] The upper electrode grounding ring is arranged on the bottom surface of the gas uniforming disk and is sleeved on the outer side of the upper electrode isolation ring. A second gap is provided between the upper electrode grounding ring and the upper electrode isolation ring, and the second gap is connected to the annular gas outlet channel.

[0029] Optionally, a protrusion is provided on the side of the dielectric window, and a flange is provided on the inner side of the upper electrode isolation ring close to the bottom surface. The protrusion cooperates with the flange, and the bottom surface of the dielectric window is flush with the bottom surface of the upper electrode isolation ring.

[0030] Optionally, the protruding portion and the flange are positioned by a positioning pin.

[0031] Optionally, an annular boss is provided on the bottom surface of the upper electrode isolation ring, the annular boss is arranged along the outer ring edge of the upper electrode isolation ring, and the outer side wall of the annular boss is flush with the outer side wall of the upper electrode isolation ring.

[0032] Optionally, the distance between the bottom surface of the annular boss and the bottom surface of the upper electrode isolation ring is less than or equal to 1 mm.

[0033] Optionally, a first annular sealing ring is provided between the top surface of the upper electrode isolation ring and the bottom surface of the gas uniforming disk;

[0034] A second annular sealing ring is provided between the top surface of the upper electrode grounding ring and the bottom surface of the gas uniforming disk;

[0035] The first annular sealing ring and the second annular sealing ring seal the annular air outlet channel from both inside and outside.

[0036] In a second aspect, an embodiment of the present application further provides a process chamber, comprising a chamber body and an upper electrode cover plate covering a top opening of the chamber, and further comprising the upper electrode assembly as described in the above embodiments;

[0037] The gas distribution plate is located in the cavity;

[0038] The conductive connecting tube passes through the upper electrode cover plate and extends to the outside of the cavity. The conductive connecting tube is connected to the upper electrode cover plate through a bellows.

[0039] Optionally, the process chamber further comprises a lower electrode assembly disposed opposite to the upper electrode assembly;

[0040] The lower electrode assembly comprises:

[0041] base;

[0042] a lower electrode isolation ring, sleeved on the outer side of the base plate, wherein the top surface of the lower electrode isolation ring is higher than the top surface of the base plate;

[0043] a bottom insulating ring, arranged on the inner bottom wall of the cavity;

[0044] A lower electrode interface disk is connected to the inner ring of the bottom insulating ring, and a through hole is provided in the center of the lower electrode interface disk;

[0045] A vacuum mechanical chuck is provided on the top surface of the bottom insulating ring and the top surface of the lower electrode interface plate, and a blind hole communicating with the through hole is provided at the center of the bottom surface of the vacuum mechanical chuck for connecting to the feed end of the radio frequency source;

[0046] A middle insulating ring is sleeved on the outside of the vacuum mechanical chuck and is connected to the bottom insulating ring;

[0047] The bottom surface of the base plate abuts against the top surface of the vacuum mechanical chuck;

[0048] The bottom surface of the lower electrode isolation ring abuts against the top surface of the vacuum mechanical chuck and the top surface of the middle insulating ring.

[0049] Optionally, the process chamber further includes:

[0050] a lower electrode grounding ring, sleeved on the outer side of the lower electrode isolation ring, wherein the top surface of the lower electrode grounding ring is lower than the top surface of the lower electrode isolation ring, and the lower electrode grounding ring is cooperatively connected with the top surface and side surface of the middle insulating ring;

[0051] An inner liner, which is sleeved on the outer side of the middle insulating ring and has a top surface connected to the lower electrode grounding ring;

[0052] A conductive ring is sleeved on the outside of the middle insulating ring and the outside of the bottom insulating ring, and the top surface of the conductive ring is connected to the lining, the bottom surface of the conductive ring is supported on the inner bottom wall of the cavity, and the outer side surface of the conductive ring abuts against the inner wall of the cavity.

[0053] In a third aspect, an embodiment of the present application further provides a semiconductor processing device, comprising the process chamber described in the above embodiments.

[0054] As described above, in the upper electrode assembly of the present application, when the gas supply source inputs process gas into the central air inlet channel of the conductive connecting tube, the process gas enters the uniform gas disk from the central air vent along the central air inlet channel, and after passing through the uniform gas disk, finally reaches the central area of ​​the wafer. On the other hand, the gas supply source inputs process gas into the edge air inlet channel of the conductive connecting tube, and the process gas enters the uniform gas disk from the annular air inlet channel along the edge air inlet channel, and then passes through the connecting channel and the annular air outlet channel in sequence, and finally reaches the edge area of ​​the wafer. The gas in the central area can prevent the plasma generated in the edge area from entering the central area of ​​the wafer. Since the process gas is output from the annular air outlet channel, the gas distribution effect mapped on the edge surface of the wafer is an annular band distribution, which is uniformly distributed, thereby improving the uniformity of wafer edge etching. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] The accompanying drawings herein are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for describing the embodiments. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without inventive work.

[0056] Figure 1 This is a schematic structural diagram of an existing upper electrode assembly;

[0057] Figure 2 It is a schematic diagram of the structure of an existing grounded metal plate viewed from above;

[0058] Figure 3 1 is a schematic cross-sectional structural diagram of a process chamber provided in an embodiment of the present application;

[0059] Figure 4 This is a schematic diagram of the internal structure of an air distribution disk provided in an embodiment of the present application;

[0060] Figure 5 yes Figure 3 Schematic diagram of the enlarged structure of part A;

[0061] Figure 6This is a structural diagram of an air intake passage in related technology;

[0062] Figure 7 yes Figure 3 Schematic diagram of the enlarged structure of part B;

[0063] The purpose of this application, its features, and advantages will be further described in conjunction with the embodiments and with reference to the accompanying drawings. The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and the accompanying text are not intended to limit the scope of the present application in any way, but rather to illustrate the concepts of this application to those skilled in the art by reference to specific embodiments. DETAILED DESCRIPTION

[0064] Exemplary embodiments will be described in detail herein, with examples illustrated in the accompanying drawings. In the following description, when referring to the drawings, identical numerals in different figures represent identical or similar elements, unless otherwise indicated. The embodiments described in the following exemplary embodiments are not intended to represent all embodiments consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present application, as detailed in the appended claims.

[0065] It should be noted that, in this document, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element. In addition, components, features, and elements with the same name in different embodiments of the present application may have the same meaning or different meanings, and their specific meanings need to be determined by their explanation in the specific embodiment or further combined with the context of the specific embodiment.

[0066] It should be understood that although the terms "first," "second," "third," etc. may be used herein to describe various types of information, such information should not be limited to these terms. These terms are merely used to distinguish information of the same type from one another. For example, first information may be referred to as second information, and similarly, second information may be referred to as first information without departing from the scope of this disclosure.

[0067] Depending on the context, the word "if" as used herein can be interpreted as "at the time of" or "when" or "in response to determining". Furthermore, as used in this article, the singular forms "a", "an" and "the" are intended to also include the plural forms, unless there is an opposite indication in the context. It should be further understood that the terms "comprising" and "including" indicate the presence of the described features, steps, operations, elements, components, projects, kinds, and / or groups, but do not exclude the presence, occurrence or addition of one or more other features, steps, operations, elements, components, projects, kinds, and / or groups. The terms "or", "and / or", "including at least one of the following" etc. used in this application can be interpreted as inclusive, or mean any one or any combination. For example, “comprising at least one of the following: A, B, C” means “any of the following: A; B; C; A and B; A and C; B and C; A and B and C”; and for another example, “A, B or C” or “A, B and / or C” means “any of the following: A; B; C; A and B; A and C; B and C; A and B and C”. An exception to this definition will occur only when a combination of elements, functions, steps or operations are inherently mutually exclusive in some manner.

[0068] It should be understood that, although the various steps in the flowchart in the embodiment of the present application are shown in sequence according to the indication of the arrows, these steps are not necessarily performed in sequence in the order indicated by the arrows. Unless clearly stated herein, the execution of these steps is not strictly limited in order, and they can be performed in other orders. Moreover, at least a portion of the steps in the figure may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily performed at the same time, but can be performed at different times, and their execution order is not necessarily performed in sequence, but can be performed in turn or alternately with at least a portion of other steps or sub-steps or stages of other steps.

[0069] It should be understood that the terms "top", "bottom", "up", "down", "vertical", "horizontal", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0070] For ease of description, the following embodiments are all described using the orthogonal space formed by the horizontal plane and the vertical direction as an example. This premise should not be understood as a limitation to the present application.

[0071] See also Figure 3 , Figure 3The figure is a schematic cross-sectional view of a process chamber according to an embodiment of the present application, in which an upper electrode assembly 10 is applied. The upper electrode assembly 10 includes a conductive connecting tube 11 and a gas distribution plate 12 connected to the bottom end of the conductive connecting tube 11.

[0072] As an example, the conductive connecting tube 11 can be a metal connecting tube with good electrical conductivity. The conductive connecting tube 11 is provided with a central gas inlet channel 111 and multiple edge gas inlet channels 112. It is understood that the central gas inlet channel 111 and the edge gas inlet channels 112 can be pipes disposed within the conductive connecting tube 11. As an example, the multiple edge gas inlet channels 112 can be evenly distributed in one or more circles centered around the central gas inlet channel 111. A gas supply can deliver process gas into the process chamber through the central gas inlet channel 111 and the edge gas inlet channels 112.

[0073] Please also see Figure 4 , Figure 4 It is a schematic diagram of the internal structure of an air distribution disk provided in an embodiment of the present application. The air distribution disk 12 includes a central air vent H, an annular air inlet channel 201, a connecting channel 202 and an annular air outlet channel 203, wherein the central air vent H is used to guide the gas to the central area of ​​the wafer 100, and the annular air outlet channel 203 is used to guide the gas to the edge area of ​​the wafer 100. The annular air inlet channel 201 is arranged around the central air vent H, and the annular air outlet channel 203 is arranged around the annular air inlet channel 201. The connecting channel 202 connects the annular air inlet channel 201 and the annular air outlet channel 203. The central air vent H can be a through hole. As an example, the central air vent H is arranged at the center of the air distribution disk 12 and passes through the bottom surface of the air distribution disk 12 from the top surface of the air distribution disk 12; the annular air inlet channel 201 and the annular air outlet channel 203 are concentrically arranged with the center of the air distribution disk 12 as the center of the circle. The central air inlet channel 111 of the conductive connecting tube 11 is connected to the central air vent H of the gas leveling disk 12. The central air vent H is used to guide the gas flowing into the central air inlet channel 111 to the central area of ​​the wafer 100, forming a central air supply system. The edge air inlet channel 112 of the conductive connecting tube 11 is connected to the annular air inlet channel 201 of the gas leveling disk 12. The annular air outlet channel 203 is used to guide the gas flowing into the edge air inlet channel 201 to the edge area of ​​the wafer 100, forming an edge air supply system. It can be understood that the central air supply system and the edge air supply system are two independent systems, and their flow rates can be controlled separately.

[0074] The gas supply principle of the upper electrode assembly 10 of this embodiment is as follows: the gas supply source inputs process gas into the central gas inlet channel 111 of the conductive connecting tube 11. The process gas flows along the central gas inlet channel 111 into the gas uniforming disk 12 from the central vent H. After passing through the gas uniforming disk 12, it finally reaches the center area of ​​the wafer 100. On the other hand, the gas supply source inputs process gas into the edge gas inlet channel 112 of the conductive connecting tube 11. The process gas flows along the edge gas inlet channel 112 from the annular gas inlet channel 201 into the gas uniforming disk 12, and then passes through the connecting channel 202 and the annular gas outlet channel 203 in sequence, finally reaching the edge area of ​​the wafer 100. The gas in the central area can prevent the plasma generated in the edge area from entering the center area of ​​the wafer 100. Since the process gas is output from the annular gas outlet channel 203, the gas distribution effect reflected on the edge surface of the wafer 100 is an annular band distribution, which is uniform, thereby improving the uniformity of edge etching of the wafer 100.

[0075] As an embodiment of the gas distribution plate 12, please continue to refer to Figure 3 and Figure 4 The gas-distributing disk 12 includes an annular bottom plate 121, a circular bottom plate 122, and a top plate 123. The circular bottom plate 122 is arranged on the inner ring of the annular bottom plate 121, and a first gap 103 is provided between the circumferential end surface of the circular bottom plate 122 and the inner side surface of the annular bottom plate 121; the top surface of the circular bottom plate 122 is provided with a first annular groove 101 and a plurality of connecting grooves 102, one end of the connecting groove 102 is connected to the first annular groove 101, and the other end extends to the edge of the circular bottom plate 122 and is connected to the first gap 103. The top plate 123 is arranged on the top surfaces of the circular bottom plate 122 and the annular bottom plate 121, and the first annular groove 101 is sealed to form an annular air inlet channel 201, the connecting groove 102 is sealed to form a connecting channel 202, and the top surface of the first gap 103 is sealed to form an annular air outlet channel 203. It can be understood that the air outlet of the annular air outlet channel 203 is at the edge of the bottom surface of the circular bottom plate 122. As an example, the annular bottom plate 121 and the circular bottom plate 122 can be connected to the bottom surface of the top plate 123 by welding or threading. It should be noted that the central vent hole H can be directly provided as a connecting through hole in the center of the circular bottom plate 122 and the top plate 123.

[0076] This embodiment realizes the structural setting of the annular air inlet channel 201, the connecting channel 202 and the annular air outlet channel 203 of the air uniforming disk 12 through the ingenious design and assembly of three plates: the annular bottom plate 121, the circular bottom plate 122 and the top plate 123. The processing and assembly are relatively simple and the cost is low.

[0077] In order to buffer the large flow of process gas and make the process gas flow more uniform, in one embodiment, please continue to refer to Figure 4The top surface of the circular base plate 122 may also be provided with a second annular groove 105. The second annular groove 105 is provided around the outside of the first annular groove 101. For example, the two may be provided concentrically. The multiple connecting grooves 102 include multiple first sub-connecting grooves 102a and multiple second sub-connecting grooves 102b. One end of the first sub-connecting groove 102a is connected to the first annular groove 101, and the other end is connected to the second annular groove 105. One end of the second sub-connecting groove 102b is connected to the second annular groove 105, and the other end is connected to the first gap 103. The top plate 123 covers the second annular groove 105 to form a buffer channel 205. The top plate 123 covers the first sub-connecting groove 102a to form a first sub-connecting channel 202a. The top plate 123 covers the second sub-connecting groove 102b to form a second sub-connecting channel 202b.

[0078] In the gas uniforming disk 12 of this embodiment, the process gas enters the gas uniforming disk 12 from the annular air inlet channel 201, then enters the buffer channel 205 through the first sub-connecting channel 202a, and then enters the second sub-connecting channel 202b, and is finally output from the annular air outlet channel 203. The buffer channel 205 can buffer the large flow process gas, and can converge the process gas flowing into each first sub-connecting channel 202a. The process gas is uniformly treated once in the buffer channel 205, reducing the difference in gas flow in each subsequent channel. Preferably, the number of the second sub-connecting grooves 102b is greater than the number of the first sub-connecting grooves 102a, and can be designed according to the requirements of the annular air outlet channel 203 for the air flow velocity. As an example, the number of the second sub-connecting grooves 102b is twice the number of the first sub-connecting grooves 102a. Of course, in other embodiments, multiple annular grooves can be sequentially set on the outer ring of the second annular groove 105 to perform multi-stage buffering, which will not be described in detail in this application.

[0079] Since a lot of heat is generated during the etching process, the temperature of the gas plate 12 in the process chamber will gradually increase. In order to cool the gas plate 12, in one embodiment, refer to Figure 3-Figure 5 , Figure 5 yes Figure 3 In the enlarged structural diagram of section A, top plate 123 may include a lower top plate 1231 and an upper top plate 1232. Lower top plate 1231 is disposed on the top surfaces of circular bottom plate 122 and annular bottom plate 121, and is provided with a coolant groove 107 on its top surface. Upper top plate 1232 is disposed on the top surface of lower top plate 1231, sealing the coolant groove to form a coolant channel 207. The structural design principles of coolant channel 207 are consistent with those of the aforementioned annular inlet channel 201, connecting channel 202, and annular outlet channel 203, and will not be further described in this embodiment.

[0080] In order to prevent the plasma in the process chamber from flowing back into the process gas inlet channel and causing corrosion to the inner wall of the inlet channel, the relevant technology generally changes the vertical inlet channel into a tortuous inlet channel. Figure 6 , Figure 6 This is a schematic diagram of the structure of an air inlet channel in related technology. In this solution, a transverse channel 201A connects two longitudinal channels 202A and 203A. The transverse channel 201A effectively protects the longitudinal channel 202A. However, this solution increases the length of the air inlet channel. Because different process steps require switching between different process gases, an excessively long air inlet channel reduces the response time for the process gas to enter the wafer, thereby extending the control response time of the entire tool.

[0081] In order to solve the problem of plasma backflow without increasing the length of the gas inlet channel, in one embodiment, an annular constriction is provided near the bottom of the annular gas outlet channel, which can increase the gas pressure when flowing through the annular constriction and prevent the internal plasma from backflowing. As an example, please refer to Figure 7 , Figure 7 yes Figure 3 In the enlarged structural diagram of part B, the circumferential end surface (i.e., the outer surface) of the circular base plate 122 is provided with a first annular protrusion 1221, and the inner surface of the annular base plate 121 is provided with a second annular protrusion 1211. The first annular protrusion 1221 is opposite to the second annular protrusion 1211, so that an annular constriction 104 is formed in the annular gas outlet channel 203. As an example, the width of the annular gas outlet channel 203 can be 2mm, and the width of the annular constriction 104 can be less than 1mm, such as 1mm, 0.8mm, 0.6mm, 0.5mm, etc. After the process gas enters the annular gas outlet channel 203 and flows through the annular constriction 104, the airflow pressure increases due to the smaller diameter, and the process gas accelerates to flow downward, thereby preventing the plasma in the process chamber from backflowing, and there is no need to increase the length of the gas inlet channel.

[0082] It should be noted that the cross-sections of the first annular protrusion 1221 and the second annular protrusion 1211 can be smooth arcs or broken lines, which are not particularly limited in the present embodiment. Figure 7The inner side surface of the annular bottom plate 121 includes, from top to bottom: a first vertical surface 1212, a first inclined surface 1213 bent from the first vertical surface 1212 toward the circumferential end surface of the circular bottom plate 122, and a second vertical surface 1214 connected to the first inclined surface 1213. The second annular protrusion 1211 is formed by the first inclined surface 1213 and the second vertical surface 1214. The circumferential end surface of the circular bottom plate 122 includes, from top to bottom: a third vertical surface 1222, a second inclined surface 1223 bent from the third vertical surface 1222 toward the annular bottom plate 121, and a third inclined surface 1224 bent from the second inclined surface 1223 toward a direction away from the annular bottom plate 121. The first annular protrusion 1221 is formed by the second inclined surface 1223 and the third inclined surface 1224. The annular constriction 104 structure of this embodiment can accelerate the downward flow of gas and can cover all areas of the edge of the wafer 100, making etching more uniform.

[0083] In one embodiment, see Figure 3 and Figure 7 The upper electrode assembly 10 includes a conductive connecting tube 11, a gas uniforming disk 12, a dielectric window 13, an upper electrode isolation ring 14, and an upper electrode grounding ring 15. The gas uniforming disk 12 is connected to the bottom end of the conductive connecting tube 11, and the dielectric window 13 is arranged on the bottom surface of the gas uniforming disk 12. For example, a positioning groove can be provided on the bottom surface of the gas uniforming disk 12, and a boss that matches the positioning groove can be provided on the top surface of the dielectric window 13 to achieve the installation and positioning of the two. It can be understood that a through hole that communicates with the central vent H is provided on the dielectric window 13 so that the process gas entering the central air inlet channel 111 can reach the central area of ​​the wafer 100 and prevent plasma from entering the central area of ​​the wafer 100. The upper electrode isolation ring 14 is provided on the bottom surface of the gas uniforming disk 12 and is sleeved on the outside of the dielectric window 13. The upper electrode isolation ring 14 is used to isolate the central area of ​​the wafer 100, so that the plasma only etches the edge of the wafer 100. It can be made of a dielectric material such as Al2O3. The upper electrode grounding ring 15 is arranged on the bottom surface of the gas uniforming disk 12 and is sleeved on the outer side of the upper electrode isolation ring 14. A second gap 106 is provided between the upper electrode grounding ring 15 and the upper electrode isolation ring 14, and the second gap 106 is connected to the annular gas outlet channel 203. Preferably, the inner side surface of the upper electrode grounding ring 15 is flush with the outer side wall at the outlet of the annular gas outlet channel 203. For example, the second vertical surface 1214 of the annular bottom plate 121 is flush with the inner side surface of the upper electrode grounding ring 15. The width of the second gap 106 can be adjusted by replacing the upper electrode isolation ring 14 with different outer diameters, thereby adjusting the width of the gas outlet of the gas outlet channel. In addition, the inner side surface of the upper electrode grounding ring 15 is preferably flush with the outer side surface of the wafer 100 below, so that the plasma generated in the process chamber can better etch the upper and lower edge surfaces of the wafer 100.

[0084] In the traditional structure, the upper electrode isolation ring is sleeved on the dielectric window and fixed by the flange on the bottom of the dielectric window and the conductive member above. When installing and removing the upper electrode isolation ring 14, the dielectric window 13 needs to be installed and removed first. The installation and removal process is cumbersome, and after installation, a special tool is required to adjust the second gap 106 between the upper electrode isolation ring 14 and the upper electrode grounding ring 15. As an example of the connection between the upper electrode isolation ring 14 and the dielectric window 13, please continue to refer to Figure 7 For example, a protrusion 131 can be provided on the side of the dielectric window 13, and a flange 141 can be provided on the inner side surface of the upper electrode isolation ring 14 near the bottom surface. The protrusion 131 cooperates with the flange 141, and the bottom surface of the dielectric window 13 is flush with the bottom surface of the upper electrode isolation ring 14. In addition, the upper electrode isolation ring 14 and the dielectric window 13 can be positioned by a positioning pin 132 and then fixed with a countersunk screw. For example, two positioning pins 132 can be used for positioning, and then countersunk screws evenly distributed in a ring can be used for fixing. In this embodiment, the upper electrode isolation ring 14 and the dielectric window 13 are positioned by positioning pins. During the installation and disassembly process (such as replacing a different upper electrode isolation ring 14), after the upper electrode assembly 10 is opened and lifted, the countersunk screws on the upper electrode isolation ring 14 can be removed for disassembly and assembly. There is no need to adjust the gap between the upper electrode isolation ring 14 and the upper electrode grounding ring 15, and maintenance is simple.

[0085] In order to improve the sealing performance of the connection between the annular air outlet channel 203 and the second gap 106, in one embodiment, please continue to refer to Figure 7 A first annular sealing ring 301 is provided between the top surface of the upper electrode isolation ring 14 and the bottom surface of the gas uniforming disk 12, and a second annular sealing ring 302 is provided between the top surface of the upper electrode grounding ring 15 and the bottom surface of the gas uniforming disk 12. For example, the first annular sealing ring 301 can be provided between the top surface of the upper electrode isolation ring 14 and the bottom surface of the circular bottom plate 122, and the second annular sealing ring 302 can be provided between the top surface of the upper electrode grounding ring 15 and the bottom surface of the annular bottom plate 121. The first annular sealing ring 301 and the second annular sealing ring 302 seal the annular gas outlet channel 203 from both the inside and the outside. This can prevent the flow loss of process gas and the plasma at the edge from entering the installation gap of the components and contaminating the components.

[0086] During wafer etching, the wafer 100 is supported on the lower electrode isolation ring 32. Since the top surface of the base plate 31 mounted in the lower electrode isolation ring 32 is lower than the top surface of the lower electrode isolation ring 32, there is a gap between the lower surface of the wafer 100 and the base plate 31 below. When the process gas entering through the central air inlet channel 111 reaches the central area of ​​the upper surface of the wafer 100, a pressure difference is formed between the upper and lower surfaces of the wafer 100, thereby vacuum adsorbing and fixing the wafer 100. To prevent the gas in the edge air inlet channel 112 from entering the central area of ​​the upper surface of the wafer 100 (i.e., the process isolation area), the gap between the upper surface of the wafer 100 and the lower surface of the dielectric window 13 is generally within 0.5 mm to ensure that a pressure difference is formed between the gas in the process isolation area and the edge etching area. The range in which the plasma reaches the wafer 100 is controlled by the outer diameter of the upper electrode isolation ring 14 and the above-mentioned pressure difference. During the etching process, the wafer 100 is prone to bending and deformation due to the increase in temperature under the above pressure difference. Since the inlet gas flow rate remains stable, the related art is to control the pressure by moving the dielectric window 13 upward to increase the gap between the dielectric window 13 and the upper surface of the wafer. However, this adjustment method requires high precision. In order to improve the problem of inconvenient adjustment of the bending deformation of the wafer 100 during the etching process, in one embodiment, please continue to refer to Figure 7 , an annular boss 142 may also be provided on the bottom surface of the upper electrode isolation ring 14. The annular boss 142 is provided along the outer edge of the upper electrode isolation ring 14, and the outer sidewall of the annular boss 142 is flush with the outer sidewall of the upper electrode isolation ring 14. As an example, the distance between the bottom surface of the annular boss 142 and the bottom surface of the upper electrode isolation ring 14 is less than or equal to 1 mm, that is, the height of the annular boss 142 protruding from the bottom surface of the upper electrode isolation ring 14 can be set within 1 mm, such as 1 mm, 0.8 mm, 0.5 mm, etc. The gap between the annular boss 142 and the wafer 100 is determined by the specific etching process, such as gas flow and pressure difference requirements. In some examples, the gap can be controlled within 0.5 mm, for example, it can be set to 0.5 mm, 0.4 mm, 0.3 mm, etc.

[0087] In this embodiment, an annular boss 142 is provided on the outer edge of the upper electrode isolation ring 14 to increase the gap between the upper surface of the wafer 100 and the upper electrode isolation ring 14 , without increasing the gap by moving the dielectric window 13 upward.

[0088] This embodiment of the application also provides a process chamber, please continue to refer to Figure 3, including the upper electrode assembly 10, the cavity 20 and the upper electrode cover plate 21 as described in the above embodiments. The upper electrode cover plate 21 is covered on the top opening of the cavity 20, and forms a sealed area together with the cavity 20. The upper electrode assembly 10 includes a conductive connecting tube 11 and an air uniforming disk 12, and the air uniforming disk 12 is located in the cavity 20; the conductive connecting tube 11 passes through the upper electrode cover plate 21 and extends to the outside of the cavity 20, and the conductive connecting tube 11 is connected to the upper electrode cover plate 21 through a bellows 303, so that the conductive connecting tube 103 drives the upper electrode assembly 10 to move up and down to control the gap between the upper electrode assembly 10 and the wafer 100, while ensuring that the inside of the cavity 20 is in a sealed state. In this embodiment, the air uniforming disk 12, the metal connecting tube 11, the upper electrode cover plate 21 and the cavity 20 can form a grounding loop.

[0089] As an example, see Figure 3 The process chamber may further include a lower electrode assembly 30, which is disposed opposite the upper electrode assembly 10. The lower electrode assembly 30 includes a base plate 31, a lower electrode isolation ring 32, a bottom insulating ring 34, a lower electrode interface plate 35, a vacuum mechanical chuck 36, and a middle insulating ring 37.

[0090] The base plate 31 can be made of a ceramic dielectric material. The lower electrode isolation ring 32 is sleeved onto the outer surface of the base plate 31. The two can be positioned on the side using a concave-convex nesting structure. The top surface of the lower electrode isolation ring 32 is higher than the top surface of the base plate 31, allowing the wafer 100 to be supported on the top surface of the lower electrode isolation ring 32. This creates a vacuum between the wafer 100 and the base plate 31, allowing the wafer 100 to be fixed by vacuum suction during etching. A bottom insulating ring 34 is mounted on the inner bottom wall of the chamber 20. The lower electrode interface plate 35 is connected to the inner ring of the bottom insulating ring 34 and has a through hole at its center. As an example, the lower electrode interface plate 35 can be flush with the top surface of the bottom insulating ring 34. A vacuum mechanical chuck 36 is mounted on the top surfaces of the bottom insulating ring 34 and the lower electrode interface plate 35. A blind hole is located at the center of the bottom surface of the vacuum mechanical chuck 36, connected to the through hole and used to connect to the feed port of the RF source 38. The middle insulating ring 37 is mounted on the outside of the vacuum machine chuck 36 and is mated with the bottom insulating ring 34. The bottom surface of the base plate 31 abuts the top surface of the vacuum machine chuck 36. The bottom surface of the lower electrode isolation ring 32 abuts the top surface of the vacuum machine chuck 36 and the top surface of the middle insulating ring 37.

[0091] For further information, please refer to Figure 3The process chamber may also include a lower electrode grounding ring 33, an inner liner 39, and a conductive ring 41. The lower electrode grounding ring 33 is sleeved on the outside of the lower electrode isolation ring 32. The top surface of the lower electrode grounding ring 33 is lower than the top surface of the lower electrode isolation ring 32. The lower electrode grounding ring 33 is matingly connected to the top and side surfaces of the middle insulating ring 37. The inner liner 39 is sleeved on the outside of the middle insulating ring 37 and connected to the lower electrode grounding ring 33 on its top surface. For example, the lower electrode grounding ring 33 can be mounted to the inner liner 39 by screwing from the bottom. The conductive ring 41 is sleeved on the outside of the middle insulating ring 37 and the outside of the bottom insulating ring 34. The top surface of the conductive ring 41 is connected to the inner liner 39. The bottom surface of the conductive ring 41 is supported on the inner bottom wall of the chamber 20, and the outer surface of the conductive ring 41 abuts the inner wall of the chamber 20. The entire reaction chamber assembly mainly consists of the lower electrode grounding ring 33, the inner liner 39, the conductive ring 41, and the chamber 20. In this embodiment, the lower electrode grounding ring 33, the lining 39, the conductive ring 41 and the cavity 20 are interconnected to form a conductive grounding loop, and the annular isolation area composed of the lower electrode isolation ring 32, the bottom insulating ring 34 and the middle insulating ring 37 electrically isolates the above-mentioned grounding loop from the RF source 38.

[0092] An embodiment of the present application further provides a semiconductor processing device, which may include the upper electrode assembly described in the above embodiments, or include the process chamber described in the above embodiments.

[0093] It should be noted that in this embodiment, all components that pose a certain risk of exposure to the plasma environment can undergo surface protection treatment, either entirely or locally. For example, the upper electrode isolation ring 14, the upper electrode grounding ring 15, countersunk screws, etc. can undergo hard anodizing or other corrosion-resistant surface treatments, such as spraying Y2O3 on the surface of the components.

[0094] The above describes in detail the upper electrode assembly, process chamber, and semiconductor processing equipment provided by this application. This article uses specific examples to illustrate the principles and implementation methods of this application. It should be noted that in this application, the descriptions of each embodiment have their own emphases. For portions not detailed or recorded in a particular embodiment, reference can be made to the relevant descriptions of other embodiments.

[0095] The various technical features of the technical solution of this application can be combined arbitrarily. In order to make the description concise, not all possible combinations of the various technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0096] The above are only preferred embodiments of the present application and do not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. An upper electrode assembly, used in a process chamber of a semiconductor processing equipment, characterized in that: It includes a conductive connecting tube and an air-distributing plate connected to the bottom end of the conductive connecting tube; A central air inlet channel and a plurality of edge air inlet channels are provided in the conductive connecting tube; The air distribution plate includes a central air vent, an annular air inlet channel arranged around the central air vent, an annular air outlet channel arranged around the annular air inlet channel, and a plurality of connecting channels connecting the annular air inlet channel and the annular air outlet channel; The central air inlet channel is in communication with the central air vent, and the central air vent is used to guide the gas flowing into the central air inlet channel to the central area of ​​the wafer; The edge air inlet channel is connected to the annular air inlet channel, and the annular air outlet channel is used to guide the gas flowing into the edge air inlet channel to the edge area of ​​the wafer, and the gas distribution effect mapped on the edge surface of the wafer is an annular band distribution.

2. The upper electrode assembly according to claim 1, wherein: An annular constriction is provided in an area near the bottom of the annular air outlet channel.

3. The upper electrode assembly according to claim 2, wherein: The aerator comprises: annular base plate; A circular bottom plate is provided on the inner ring of the annular bottom plate, and a first gap is provided between the circumferential end surface of the circular bottom plate and the inner side surface of the annular bottom plate; a first annular groove and a plurality of connecting grooves are provided on the top surface of the circular bottom plate, one end of the connecting groove is connected to the first annular groove, and the other end extends to the edge of the circular bottom plate and is connected to the first gap; a first annular protrusion is provided in an area near the bottom of the circumferential end surface of the circular bottom plate, and a second annular protrusion is provided on the inner side surface of the annular bottom plate, the first annular protrusion and the second annular protrusion are opposite to each other to form the annular constriction in the annular air outlet channel; A top plate is arranged on the top surfaces of the circular bottom plate and the annular bottom plate, covers the first annular groove to form the annular air inlet channel, covers the connecting groove to form the connecting channel, and covers the top surface of the first gap to form the annular air outlet channel.

4. The upper electrode assembly according to claim 3, wherein: The inner side surface of the annular bottom plate includes, from top to bottom, a first vertical surface, a first inclined surface bent from the first vertical surface toward the circumferential end surface of the circular bottom plate, and a second vertical surface connected to the first inclined surface, wherein the second annular protrusion is formed by the first inclined surface and the second vertical surface; The circumferential end surface of the circular base plate includes, from top to bottom, a third vertical surface, a second inclined surface bent from the third vertical surface toward the annular base plate, and a third inclined surface bent from the second inclined surface toward a direction away from the annular base plate, and the first annular protrusion is formed by the second inclined surface and the third inclined surface.

5. The upper electrode assembly according to claim 3, wherein: The top surface of the circular bottom plate is further provided with a second annular groove surrounding the outside of the first annular groove; The plurality of connection grooves include a plurality of first sub-connection grooves and a plurality of second sub-connection grooves; One end of the first sub-connecting groove is connected to the first annular groove, and the other end is connected to the second annular groove; One end of the second sub-connecting groove is connected to the second annular groove, and the other end is connected to the first gap; The top plate covers the second annular groove to form a buffer channel.

6. The upper electrode assembly according to claim 3, characterized in that The top plate comprises: A lower top plate is provided on the top surfaces of the circular bottom plate and the annular bottom plate; the top surface of the lower top plate is provided with a coolant groove; The upper top plate is arranged on the top surface of the lower top plate and covers the coolant groove to form a coolant channel.

7. The upper electrode assembly according to claim 1, wherein: Also includes: A medium window is provided on the bottom surface of the gas uniforming disk; An upper electrode isolation ring is provided on the bottom surface of the gas uniforming disk and sleeved on the outer side of the dielectric window; The upper electrode grounding ring is arranged on the bottom surface of the gas uniforming disk and is sleeved on the outer side of the upper electrode isolation ring. A second gap is provided between the upper electrode grounding ring and the upper electrode isolation ring, and the second gap is connected to the annular gas outlet channel.

8. The upper electrode assembly according to claim 7, wherein: A convex portion is provided on the side of the dielectric window, and a flange is provided on the inner side of the upper electrode isolation ring close to the bottom surface. The convex portion cooperates with the flange, and the bottom surface of the dielectric window is flush with the bottom surface of the upper electrode isolation ring.

9. The upper electrode assembly according to claim 8, characterized in that: The protruding portion and the flange are positioned by a positioning pin.

10. The upper electrode assembly according to claim 7, wherein: An annular boss is provided on the bottom surface of the upper electrode isolation ring. The annular boss is arranged along the outer edge of the upper electrode isolation ring, and the outer side wall of the annular boss is flush with the outer side wall of the upper electrode isolation ring.

11. The upper electrode assembly according to claim 10, wherein: The distance between the bottom surface of the annular boss and the bottom surface of the upper electrode isolation ring is less than or equal to 1 mm.

12. The upper electrode assembly according to claim 7, wherein: A first annular sealing ring is provided between the top surface of the upper electrode isolation ring and the bottom surface of the gas uniforming disk; A second annular sealing ring is provided between the top surface of the upper electrode grounding ring and the bottom surface of the gas uniforming disk; The first annular sealing ring and the second annular sealing ring seal the annular air outlet channel from both inside and outside.

13. A process chamber comprising a chamber body and an upper electrode cover plate covering a top opening of the chamber body, characterized in that: Also comprising the upper electrode assembly according to any one of claims 1 to 12; The gas uniforming disk is located in the cavity; The conductive connecting tube passes through the upper electrode cover plate and extends to the outside of the cavity. The conductive connecting tube is connected to the upper electrode cover plate through a bellows.

14. The process chamber according to claim 13, wherein: Also included is a lower electrode assembly disposed opposite to the upper electrode assembly; The lower electrode assembly comprises: base; a lower electrode isolation ring, sleeved on the outer side of the base plate, wherein the top surface of the lower electrode isolation ring is higher than the top surface of the base plate; a bottom insulating ring, arranged on the inner bottom wall of the cavity; A lower electrode interface disk is connected to the inner ring of the bottom insulating ring, and a through hole is provided in the center of the lower electrode interface disk; A vacuum mechanical chuck is provided on the top surface of the bottom insulating ring and the top surface of the lower electrode interface plate, and a blind hole communicating with the through hole is provided at the center of the bottom surface of the vacuum mechanical chuck for connecting to the feed end of the radio frequency source; A middle insulating ring is sleeved on the outside of the vacuum mechanical chuck and is connected to the bottom insulating ring; The bottom surface of the base plate abuts against the top surface of the vacuum mechanical chuck; The bottom surface of the lower electrode isolation ring abuts against the top surface of the vacuum mechanical chuck and the top surface of the middle insulating ring.

15. The process chamber according to claim 14, wherein: Also includes: a lower electrode grounding ring, sleeved on the outer side of the lower electrode isolation ring, wherein the top surface of the lower electrode grounding ring is lower than the top surface of the lower electrode isolation ring, and the lower electrode grounding ring is cooperatively connected with the top surface and side surface of the middle insulating ring; An inner liner, which is sleeved on the outer side of the middle insulating ring and has a top surface connected to the lower electrode grounding ring; A conductive ring is sleeved on the outside of the middle insulating ring and the outside of the bottom insulating ring, and the top surface of the conductive ring is connected to the lining, the bottom surface of the conductive ring is supported on the inner bottom wall of the cavity, and the outer side surface of the conductive ring abuts against the inner wall of the cavity.

16. A semiconductor processing device, characterized in that: A process chamber comprising any one of claims 13-15.

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