CN117637420A - Bottom electrode assembly and plasma processing apparatus thereof - Google Patents
Bottom electrode assembly and plasma processing apparatus thereof Download PDFInfo
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- CN117637420A CN117637420A CN202210980421.XA CN202210980421A CN117637420A CN 117637420 A CN117637420 A CN 117637420A CN 202210980421 A CN202210980421 A CN 202210980421A CN 117637420 A CN117637420 A CN 117637420A
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Abstract
The invention discloses a lower electrode assembly and a plasma processing device thereof, wherein the lower electrode assembly comprises: a susceptor including a boss portion carrying a substrate, and a supporting portion surrounding an outer periphery of the boss portion and having an upper surface lower than the boss portion; an insulating ring located above the supporting portion and surrounding the boss portion; an edge ring located above the insulating ring; wherein, be provided with the ring channel on the insulating ring and be used for imbedding the edge ring. According to the invention, the edge ring is embedded into the annular groove, so that the equivalent capacitance from the base to the edge ring is increased under the condition that the height of the edge ring is not changed, the plasma sheath layer distribution from the upper part of the edge of the substrate to the upper part of the edge ring is improved, the plasma etching direction of the edge of the substrate is vertical to the substrate, and the inclination of the etching holes at the edge of the substrate can be effectively avoided.
Description
Technical Field
The present invention relates to the field of semiconductor devices and their fabrication, and more particularly, to a lower electrode assembly and a plasma processing apparatus thereof.
Background
The vacuum reaction chamber of the plasma processing device comprises a base for supporting a substrate, a focusing ring is arranged around the base, etching gas is introduced into the vacuum reaction chamber, and the etching gas is distributed to a central area of the substrate and an edge area adjacent to the central area according to the flow rate proportion.
When the substrate is etched, the etching gas forms plasmas under the action of radio frequency excitation, and the plasmas and the substrate surface are subjected to physical bombardment and chemical reaction under the action of an electric field, so that the substrate surface is treated. The temperature of the focusing ring at the edge of the base is higher than that of the substrate because the temperature control device in the base cools the substrate and the temperature of the focusing ring is higher than that of the edge of the substrate. When the fluorocarbon is contained in the etching gas, the fluorocarbon is dissociated into fluorine atoms and carbon molecules under radio frequency excitation. Compared with the edge area of the substrate, the focusing ring with higher temperature consumes more fluorine atoms, carbon molecules are polymerized and accumulated in the edge area of the substrate based on the law of conservation of mass, and polymers are formed in etching holes in the edge area of the substrate, so that the progress of etching is hindered. By increasing the distance between the base and the focus ring, more carbon atoms can be accumulated on the focus ring, and the formation of polymers in etching holes in the edge region of the substrate by carbon molecules is avoided.
During substrate etching, the direction of plasma incidence is typically distorted at the edge of the substrate from a vertically downward direction in the central region of the wafer to an inclined downward direction in the edge region, resulting in an inclined angle in the feature profile of the etch hole. The plasma sheath height at the edge of the substrate is balanced by using a focus ring to eliminate the tilting effect generated at the edge of the substrate. However, after the focus ring is consumed by the plasma to reduce the thickness or increase the distance between the focus ring and the susceptor, the sheath layer over the substrate to over the edge ring bends, causing the tilting effect of the edge of the substrate to become more severe.
The statements herein merely provide background information related to the present disclosure and may not necessarily constitute prior art.
Disclosure of Invention
The invention provides a lower electrode assembly and a plasma processing device, wherein the lower electrode assembly comprises a gathering ring and an insulating ring, the insulating ring is provided with an annular groove, the focusing ring is embedded into the annular groove, the thickness of capacitance medium between the focusing ring and a base is reduced, and under the condition that the height of the focusing ring is not changed, the capacitance between the focusing ring and the base is increased, so that the edge of a substrate has a sheath layer with the same height above the focusing ring, and the inclination effect of the edge of the substrate is improved.
In order to achieve the above object, the present invention provides a lower electrode assembly comprising:
a susceptor including a boss portion carrying a substrate, and a supporting portion surrounding an outer periphery of the boss portion and having an upper surface lower than the boss portion;
an insulating ring located above the supporting portion and surrounding the boss portion;
an edge ring located above the insulating ring;
the insulating ring is provided with an annular groove for being embedded into the edge ring so as to reduce the thickness of capacitance medium between the edge ring and the supporting part, and therefore the plasma morphology above the edge ring is adjusted.
Optionally, the lower electrode assembly further comprises: and the heat conduction layer is positioned between the insulating ring and the supporting part and is used for improving the heat conduction efficiency between the insulating ring and the supporting part and reducing the temperature difference between the edge ring and the substrate.
Optionally, the bottom of the edge ring is provided with a plurality of protrusions along its circumferential direction, the protrusions being embedded in the annular groove.
Optionally, a gap is arranged between the side wall of the annular groove and the side wall of the protruding part so as to accommodate thermal expansion and contraction of the annular groove.
Optionally, a plurality of reinforcing ribs are arranged in the annular groove along the circumferential direction of the annular groove, and the reinforcing ribs are embedded between two adjacent convex parts.
Optionally, the number of the reinforcing ribs is at least 4.
Optionally, the reinforcing ribs are uniformly distributed in the annular groove.
Optionally, a blocking ring is further disposed on the insulating ring, and extends upward from an inner wall of the insulating ring, is located between the edge ring and the boss portion, and is lower than an upper surface of the boss portion, so as to electrically isolate the boss portion from the edge ring.
Optionally, gaps are formed between the side walls of the blocking ring and the side walls of the boss part and the side walls of the edge ring, so as to accommodate thermal expansion and contraction of the blocking ring.
Optionally, the edge ring comprises: and an extension ring extending inward from a sidewall of the body ring adjacent to the boss portion, at least a portion of the extension ring being located below a back surface of the substrate edge and higher than the barrier ring.
Optionally, at least a portion of the lower surface of the extension ring is in contact with the upper surface of the barrier ring.
Optionally, the body ring comprises: the device comprises an insertion ring positioned above the insulating ring and a focusing ring positioned above the insertion ring, wherein the bottom of the insertion ring is provided with a plurality of protruding parts along the circumferential direction of the insertion ring.
Optionally, the body ring comprises: and the focusing ring is positioned above the insulating ring, and a plurality of convex parts along the circumferential direction of the focusing ring are arranged at the bottom of the focusing ring.
Optionally, the insert ring is made of metal.
Optionally, a heat and electric conducting layer is arranged between the focusing ring and the inserting ring.
Optionally, the heat-conducting and electric-conducting layer adopts electric-conducting silica gel.
Optionally, the insulating ring is made of ceramic material.
Optionally, the insulating ring is made of aluminum nitride.
Optionally, a heat conducting layer is arranged between the edge ring and the insulating ring.
Optionally, the heat conducting layer is made of flexible silica gel.
The invention also provides a plasma processing device, comprising:
the reaction cavity is internally provided with the lower electrode assembly.
The invention has the following advantages:
1. the lower electrode assembly comprises an edge ring and an insulating ring positioned below the edge ring, wherein an annular groove is arranged in the insulating ring, the edge ring is embedded into the annular groove, the thickness of an equivalent capacitance medium layer between the edge ring and a supporting part can be reduced under the condition that the height of the edge ring is not changed, the equivalent capacitance from a base to the edge ring is increased, and the thickness of a plasma sheath layer formed on the upper surface of the edge ring is further raised, so that the plasma etching direction of the edge of a substrate is vertical to the substrate, and the purpose of improving the substrate edge tilting effect is achieved.
2. According to the invention, the heat conduction layer is arranged between the insulating ring and the base, so that the heat conduction efficiency between the edge ring and the base can be improved, the temperature difference between the focusing ring and the edge of the substrate is reduced, and the problem of incomplete etching of the edge of the substrate caused by accumulation of reaction byproducts in the edge region of the substrate is further reduced or completely avoided.
Drawings
Fig. 1 is a schematic structural diagram of a plasma processing apparatus according to an embodiment of the present invention.
Fig. 2a and fig. 2b are diagrams illustrating a positional relationship between a base and an edge ring according to an embodiment of the present invention.
FIG. 3 is a schematic view of a plasma sheath from above the edge of a substrate to above the edge ring after increasing the distance between the susceptor and the edge ring according to an embodiment of the present invention.
Fig. 4 is a schematic view showing a partial structure of a lower electrode assembly according to an embodiment of the present invention.
FIG. 5 is a schematic view of a plasma sheath from above the edge of a substrate to above the edge ring after modification in accordance with an embodiment of the present invention.
FIG. 6 is a schematic view of a structure in which protrusions are distributed at the bottom of a focus ring according to an embodiment of the present invention.
Fig. 7 is a schematic structural diagram of an insulating ring according to an embodiment of the present invention.
Fig. 8 is a schematic view showing a partial structure of a lower electrode assembly according to other embodiments of the present invention.
Detailed Description
The invention is described in further detail below with reference to the drawings and the specific examples. Advantages and features of the invention will become more apparent from the following description and from the claims. It is noted that the drawings are in a very simplified form and utilize non-precise ratios, and are intended to facilitate a convenient, clear, description of the embodiments of the invention.
Fig. 1 is a schematic diagram of a plasma processing apparatus according to the present embodiment. The plasma processing apparatus comprises a vacuum reaction chamber 1 for preparing a semiconductor device. The bottom of the vacuum reaction chamber 1 is provided with a base and can be used as a lower electrode. The central area of the base is higher than the edge area, a boss part 4 is formed in the central area and is used for bearing and fixing the substrate 3 to be processed, a supporting part 7 is formed around the periphery of the boss part 4 in the edge area, and the upper surface of the supporting part 7 is lower than the upper surface of the boss part 4. The substrate 3 comprises a substrate and a dielectric layer of a laminated structure, and common dielectric layer materials comprise silicon dioxide, silicon nitride, carbon-containing silicon nitride, low dielectric constant materials and the like. The top of the vacuum reaction chamber 1 is provided with a gas spray head 2, and can also be used as an upper electrode for conveying etching gas (composed of one or more gases) into the vacuum reaction chamber 1. And a high-frequency radio-frequency power supply applies a high-frequency radio-frequency signal to the base so as to form a radio-frequency electric field between the upper electrode and the lower electrode, and the etching gas in the vacuum reaction cavity 1 is excited into plasma to realize the treatment of the substrate to be treated by the plasma.
The support part 7 is provided with an edge ring 5 surrounding the boss part 4 for adjusting the plasma distribution above the edge of the substrate, so that the plasma extends above the edge ring, and the edge region of the substrate and the central region of the substrate have a sheath layer with the same thickness, thereby improving the uniformity of etching and avoiding the substrate at the same timeThe etched holes in the edge regions of the sheets are inclined. The edge ring 5 is mostly made of silicon or silicon carbide, and the heating of the plasma during etching causes the edge ring 5 to have a very high temperature. An insulating ring 6 is arranged between the edge ring 5 and the supporting part 7, so that heat of the insulating ring 6 can be conducted to the supporting part 7 with lower temperature, and the effect of cooling the edge ring 5 is achieved. However, the insulating ring 6 cannot sufficiently cool the edge ring 5, and since a temperature control device for controlling the temperature of the substrate 3 is disposed in the base, the temperature of the edge ring 5 is often higher than the temperature of the edge of the substrate. This causes the edge ring 5 to react with the plasma to form reaction byproducts, which form polymer plugs in the etched holes or trenches in the edge region of the substrate, impeding the progress of the etching. For example, the fluorocarbon in the etching gas (a commonly used fluorocarbon is CF 4 ) During etching of the substrate 3, the fluorocarbon dissociates under the action of the radio frequency electric field: CF (compact flash) 4 +e→CF 3 *+F*+e；CF 3 * And C is deposited and polymerized to form polymer and is blocked in etching holes in the edge area of the substrate, and the etching holes in the edge area of the substrate cannot be etched to the bottom of the substrate based on the law of mass conservation.
To solve the above problem, the distance between the susceptor and the edge ring may be appropriately increased, as shown in fig. 2. After the distance between the base and the edge ring is increased, more polymerization is accumulated on the position between the base and the edge ring by the reaction byproducts generated by the action of the edge ring and the plasma, so that the problem that etching holes or grooves on the edge of the substrate cannot be etched to the bottom due to the fact that the reaction byproducts are accumulated on the edge region of the substrate in a polymerization mode is avoided. Studies have shown that when the distance between the substrate 3 and the edge ring 5 is greater than 3mm, etching holes in the edge region of the substrate can be etched to the bottom of the substrate 3. However, after the distance between the susceptor and the edge ring 5 increases, as shown in fig. 3, the sheath layer from above the edge of the substrate 3 to above the edge ring 5 bends, so that the electric field in the edge region of the substrate is inclined, and thus the ions in the plasma are inclined in the direction of bombarding the edge region of the substrate, and the inclination effect of the edge of the substrate becomes more serious.
In order to improve the inclination of the etching holes in the edge region of the substrate, the present embodiment proposes a lower electrode assembly, as shown in fig. 4, comprising: a base, an insulating ring 6 and an edge ring 5. The insulating ring 6 is provided with an annular groove 10, the bottom of the edge ring 5 is embedded into the annular groove 10, the annular groove 10 is used for fixing the position of the edge ring 5 and protecting the bottom of the edge ring 5, so that breakdown discharge caused by too close distance between the edge ring 5 and a base is prevented.
The support part 7 and the edge ring 5 can be equivalent to a capacitor, and the insulating ring 6 between the support part and the edge ring is equivalent to a capacitance medium layer. The thickness of the insulating ring 6 plays a main role in equivalent capacitance between the supporting part 7 and the edge ring 5, and according to the relation between the dielectric thickness and the capacitance value between the two conductive plates, the matching between the edge ring 5 and the insulating ring 6 can reduce the thickness of a capacitance dielectric layer between the edge ring 5 and the supporting part 7 to increase the equivalent capacitance value between the base and the edge ring 5, as shown in fig. 5, further the thickness of a plasma sheath layer formed on the upper surface of the edge ring 5 is raised, so that the plasma sheath layer distribution from the upper edge of the substrate 3 to the upper edge of the edge ring 5 is improved under the condition that the height of the edge ring 5 is not changed, the plasma etching direction of the edge of the substrate 3 is vertical to the substrate 3, and the inclination of etching holes at the edge of the substrate is avoided.
The bottom of the edge ring 5 is provided with a plurality of protruding parts 11, and the protruding parts 11 are embedded into the annular groove 10. As shown in fig. 6, the protrusions 11 are uniformly distributed along the circumferential direction of the edge ring 5. The protruding portion 11 may be made of the same material as the edge ring 5, or may be made of a different material. If the protruding portion 11 and the edge ring 5 are made of different materials, the protruding portion 11 is made of other materials with conductive properties, so as to ensure that the rf electric field on the base can be coupled to the edge ring 5 through the protruding portion 11. The protruding part 11 may be integrally formed with the edge ring 5, or may be welded. If the protruding portion 11 and the edge ring 5 are connected by welding, a heat and electric conducting layer (not shown in the figure) is disposed between the contact surfaces of the protruding portion 11 and the edge ring 5, so as to ensure the coupling efficiency of the rf electric field to the edge ring 5, and simultaneously ensure the heat conduction efficiency of the edge ring 5 to the supporting portion 7 of the base. In this embodiment, the conductive layer is made of conductive silica gel. In addition, an adhesive is further disposed between the contact surfaces of the heat and electric conducting layer and the protruding portion 11 and the edge ring 5, so that the heat and electric conducting layer is in close contact with the protruding portion 11 or the edge ring 5, and the connection strength between the edge ring 5 and the protruding portion 11 is improved, and meanwhile, the electric conductivity and heat conductivity between the edge ring 5 and the protruding portion 11 are improved.
In order to increase the equivalent capacitance between the base and the edge ring 5, the thickness of the annular groove 10 in the insulating ring 6 can be further reduced. However, as the thickness of the annular groove 10 decreases, the mechanical strength of the insulating ring 6 becomes weaker, and distortion is liable to occur under stress. In order to ensure the rigidity of the annular groove 10, a plurality of reinforcing ribs 15 are arranged in the annular groove 10, as shown in fig. 7. The reinforcing ribs 15 are uniformly distributed along the circumferential direction of the annular groove 10 and are embedded between two adjacent protrusions 11. That is, the number of the reinforcing ribs 15 is the same as the number of the protrusions 11. Specifically, the number of the protruding portions 11 and the reinforcing ribs 15 is at least four. In this embodiment, the number of the protruding portions 11 and the reinforcing ribs 15 is eight.
The insulating ring 6 also serves to conduct heat from the edge ring 5 to the lower temperature support 7, lowering the temperature of the edge ring 5. The insulating ring 6 is made of a material with good heat conduction capability, so that the heat conduction efficiency of the edge ring 5 can be improved, and the temperature of the edge ring 5 is reduced, thereby reducing the temperature difference between the edge ring 5 and the edge region of the substrate 3, and further avoiding the problem that reaction byproducts are polymerized and accumulated in the edge region of the substrate, and the etched holes in the edge region of the substrate 3 cannot be etched to the bottom of the substrate 3. In this embodiment, the insulating ring 6 is made of aluminum nitride ceramic with high thermal conductivity. Since the protruding portion 11 is made of conductive metal or semiconductor, and has a coefficient of thermal expansion different from that of the insulating ring 6, in order to avoid extrusion of the insulating ring 6 due to heating, a certain gap is provided between the side wall of the protruding portion 11 and the side wall of the annular groove 10, so as to accommodate thermal expansion and contraction of the insulating ring 6.
In view of the difference in thermal expansion coefficient between the base and the edge ring 5, a certain gap is also provided between the base and the edge ring 5, which gap further increases after the distance between the edge ring 5 and the base increases. The high frequency rf power source connected to the base may cause arcing between the gaps, thereby damaging the edge ring 5 and affecting the service life of the edge ring 5. As shown in fig. 4, in this embodiment, a blocking ring 13 extends upward from the inner wall of the insulating ring 6, and the blocking ring 13 is located between the boss portion 4 and the edge ring 5 and is lower than the upper surface of the boss portion 4. The blocking ring 13 can realize the electrical isolation between the boss part 4 of the base and the edge ring 5, eliminate the radio frequency voltage difference between the base and the focusing ring 14, and effectively prevent the occurrence of arc discharge in the lower electrode assembly. In order to avoid extrusion of the baffle ring 13 caused by heating, a certain gap is arranged between the side wall of the baffle ring 13 and the side wall of the boss part 4 and between the side wall of the edge ring 5 so as to accommodate thermal expansion and contraction of the baffle ring 13.
The plasma above the edge region of the substrate may diffuse downward through the gap between the pedestal and the edge ring 5 into the gap between the barrier ring 13 and the boss portion 4 and the edge ring 5, thereby etching the pedestal and its peripheral components, causing damage to the lower electrode assembly. In order to protect the side wall of the lower electrode assembly from plasma etching, as shown in fig. 4, the edge ring 5 includes a body ring 9, and an extension ring 8 extending from the side wall of the body ring 9 toward the boss portion 4. The extension ring 8 extends at least partially below the backside of the edge of the substrate 3 and above the baffle ring 13 to block downward diffusion of the plasma. Preferably, at least part of the lower surface of the extension ring 8 is in contact with the upper surface of the barrier ring 13 to form a protective wall, protecting the side wall of the edge ring 5 from plasma etching. In this embodiment, the main body ring 9 is a focusing ring 14, and a plurality of protrusions 11 are disposed at the bottom of the focusing ring 14.
However, during the plasma etching process, the overall thickness of the edge ring 5 is thinned under the action of plasma etching and abrasion, so that the plasma sheath layer above the edge ring 5 moves downwards, and the etching holes in the edge region of the substrate are inclined again, so that the edge ring 5 needs to be replaced periodically. The edge ring 5 has a longer manufacturing period and higher manufacturing cost, and if the whole edge ring 5 is replaced, resource waste is inevitably caused. In other embodiments of the present invention, as shown in fig. 8, the main body ring 9 of the edge ring 5 includes an insert ring 17 disposed on the insulating ring 6, and a focusing ring 16 disposed on the insert ring 17, where a bottom of the insert ring 17 is provided with a plurality of protrusions 11; the extension ring 9 of the edge ring 5 extends inwardly from the side wall of the focus ring 16 adjacent to the boss portion 4. The main body ring 9 is designed into the focusing ring 16 and the inserting ring 17 which are overlapped up and down, and after the main body ring 9 is worn, only the focusing ring 16 at the upper layer is needed to be replaced, so that the waste of resources is greatly reduced. An electrically and thermally conductive layer (not shown) is disposed between the insert ring 17 and the focus ring 16, and the electrically and thermally conductive layer is made of electrically conductive silica gel, so as to improve the thermal and electrical conductivity between the focus ring 16 and the insert ring 17. In addition, an adhesive is further disposed between the contact surfaces of the conductive and heat-conductive layer and the focusing ring 16 and the inserting ring 17, so that the conductive and heat-conductive layer is in close contact with the focusing ring 16 or the inserting ring 17, and the connection strength of the lower electrode assembly is improved, and meanwhile, the heat conduction efficiency and the electric conduction efficiency between the focusing ring 16 and the inserting ring 17 can be improved.
In order to further improve the heat conduction efficiency of the edge ring 5, so as to reduce the temperature difference between the edge ring 5 and the edge region of the substrate, and reduce or completely avoid the problem of incomplete etching of the substrate 3 caused by polymerization accumulation of reaction byproducts in etching holes in the edge region of the substrate. In this embodiment, a first heat conducting layer 12 is disposed between the insulating ring 6 and the supporting portion 7, and a second heat conducting layer (not shown) is disposed between the insulating ring 6 and the main body ring 9. The first heat conduction layer 7 and the second heat conduction layer are all made of flexible silica gel. In addition, an adhesive is further disposed between the contact surfaces of the first heat conducting layer 12 and the insulating ring 6 and the supporting portion 7, or between the contact surfaces of the second heat conducting layer and the insulating ring 6 and the main body ring 9, so that the first heat conducting layer 12 and the insulating ring 6 and the supporting portion 7, and the second heat conducting layer and the insulating ring 6 and the main body ring 9 are in close contact, and the heat conduction efficiency and the electric conduction efficiency between the edge ring 5 and the supporting portion 7 can be improved while the connection strength of the lower electrode assembly is improved.
According to the invention, the edge ring 5 is embedded into the insulating ring 6, so that the thickness of a capacitance medium layer between the edge ring 5 and the supporting part 7 of the base can be reduced, the equivalent capacitance between the base and the edge ring 5 is increased, the equivalent capacitance is approximately the same as that above the edge ring 5, the thickness of a plasma sheath layer formed on the upper surface of the edge ring 5 is further raised, the sheath layer distribution from above the edge of the substrate to above the edge ring 5 is improved under the condition that the height of the edge ring 5 is not changed, the plasma etching direction of the edge of the substrate 3 is vertical to the substrate, and the inclination phenomenon of etching holes in the edge area of the substrate is avoided. In addition, the insulating ring 6 is made of aluminum nitride ceramic with high heat conductivity, and heat conducting layers are arranged between the contact surfaces of the insulating ring 6 and the supporting part 7 and between the contact surfaces of the insulating ring 6 and the edge ring 5, so that the heat conduction efficiency between the edge ring 5 and the base is improved, the temperature difference between the edge ring 5 and the edge of the substrate is reduced, and further the problem of incomplete etching of the edge of the substrate caused by accumulation of reaction byproducts in the edge region of the substrate is further reduced or completely avoided.
While the present invention has been described in detail through the foregoing description of the preferred embodiment, it should be understood that the foregoing description is not to be considered as limiting the invention. Many modifications and substitutions of the present invention will become apparent to those of ordinary skill in the art upon reading the foregoing. Accordingly, the scope of the invention should be limited only by the attached claims.
Claims (21)
1. A lower electrode assembly, comprising:
a susceptor including a boss portion carrying a substrate, and a supporting portion surrounding an outer periphery of the boss portion and having an upper surface lower than the boss portion;
an insulating ring located above the supporting portion and surrounding the boss portion;
an edge ring located above the insulating ring;
the insulating ring is provided with an annular groove for being embedded into the edge ring so as to reduce the thickness of capacitance medium between the edge ring and the supporting part, and therefore the plasma morphology above the edge ring is adjusted.
2. The lower electrode assembly of claim 1, further comprising:
and the heat conduction layer is positioned between the insulating ring and the supporting part and is used for improving the heat conduction efficiency between the insulating ring and the supporting part and reducing the temperature difference between the edge ring and the substrate.
3. The lower electrode assembly according to claim 1, wherein the bottom of the edge ring is provided with a plurality of protrusions along a circumferential direction thereof, the protrusions being fitted into the annular grooves.
4. The lower electrode assembly according to claim 3, wherein a plurality of reinforcing ribs are provided in the annular groove in a circumferential direction thereof, the reinforcing ribs being interposed between adjacent two of the protrusions.
5. The lower electrode assembly of claim 4, wherein the number of the reinforcing ribs is at least 4.
6. The lower electrode assembly of claim 5, wherein the ribs are uniformly distributed within the annular groove.
7. The lower electrode assembly of claim 3, wherein a gap is provided between the side wall of the annular groove and the side wall of the boss to accommodate thermal expansion and contraction of the annular groove.
8. The lower electrode assembly of claim 1, wherein the insulating ring is further provided with a barrier ring extending upward from an inner wall of the insulating ring, between the edge ring and the boss portion, and below an upper surface of the boss portion to electrically isolate the boss portion from the edge ring.
9. The lower electrode assembly of claim 8, wherein gaps are provided between the side walls of the separator ring and the side walls of the boss portion and the side walls of the edge ring to accommodate thermal expansion and contraction of the separator ring.
10. The lower electrode assembly of claim 8, wherein the edge ring comprises: and an extension ring extending inward from a sidewall of the body ring adjacent to the boss portion, at least a portion of the extension ring being located below a back surface of the substrate edge and higher than the barrier ring.
11. The lower electrode assembly of claim 10, wherein at least a portion of the lower surface of the extension ring is in contact with the upper surface of the barrier ring.
12. The lower electrode assembly of claim 10, wherein the body ring comprises: the device comprises an insertion ring positioned above the insulating ring and a focusing ring positioned above the insertion ring, wherein the bottom of the insertion ring is provided with a plurality of protruding parts along the circumferential direction of the insertion ring.
13. The lower electrode assembly of claim 10, wherein the body ring comprises: and the focusing ring is positioned above the insulating ring, and a plurality of convex parts along the circumferential direction of the focusing ring are arranged at the bottom of the focusing ring.
14. The lower electrode assembly of claim 12, wherein the insert ring is made of a metal material.
15. The lower electrode assembly of claim 12, wherein a thermally and electrically conductive layer is disposed between the focus ring and the insert ring.
16. The lower electrode assembly of claim 15, wherein the thermally and electrically conductive layer is an electrically conductive silicone gel.
17. The lower electrode assembly of claim 1, wherein the insulating ring is ceramic.
18. The lower electrode assembly of claim 17, wherein the insulating ring is aluminum nitride.
19. The lower electrode assembly of claim 1, wherein a thermally conductive layer is disposed between the edge ring and the insulating ring.
20. The lower electrode assembly of claim 2 or 19, wherein the thermally conductive layer is a flexible silicone gel.
21. A plasma processing apparatus, comprising:
the reaction cavity is provided with a plurality of reaction chambers,
a lower electrode assembly according to any one of claims 1 to 20 located within the reaction chamber.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210980421.XA CN117637420A (en) | 2022-08-16 | 2022-08-16 | Bottom electrode assembly and plasma processing apparatus thereof |
| TW112120892A TW202410128A (en) | 2022-08-16 | 2023-06-05 | Bottom electrode assembly and plasma processing device thereof characterized by inserting an edge ring into an annular groove, increasing an equivalent capacity from a base to the edge ring under the condition of not changing the height of the edge ring, improving the distribution of the plasma sheath from the top of a substrate edge to the top of the edge ring, and making a plasma etching direction at the substrate edge perpendicular to the substrate, so as to effectively avoid inclination of an etching hole at the substrate edge |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210980421.XA CN117637420A (en) | 2022-08-16 | 2022-08-16 | Bottom electrode assembly and plasma processing apparatus thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117637420A true CN117637420A (en) | 2024-03-01 |
Family
ID=90015155
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210980421.XA Pending CN117637420A (en) | 2022-08-16 | 2022-08-16 | Bottom electrode assembly and plasma processing apparatus thereof |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN117637420A (en) |
| TW (1) | TW202410128A (en) |
-
2022
- 2022-08-16 CN CN202210980421.XA patent/CN117637420A/en active Pending
-
2023
- 2023-06-05 TW TW112120892A patent/TW202410128A/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| TW202410128A (en) | 2024-03-01 |
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