Combined focus ring

Abstract

The present invention relates to a combined focusing ring which is separated into multiple parts and assembled so that only the part which is exposed to plasma and etched and consumed can be replaced. The present invention is characterized in that it includes: an upper plasma exposure ring which is placed on the upper outer side of an electrostatic suction cup; a lower heat-conductive support ring which is assembled to be in close contact with the lower part of the upper plasma exposure ring; a combining ring which is assembled to the outer side of the lower heat-conductive support ring; a first combining portion which combines the upper plasma exposure ring and the lower heat-conductive support ring; and a second combining portion which combines the upper plasma exposure ring and the combining ring.

Description

Technical Field

[0001] The present invention relates to a combined focus ring, and more particularly to a combined focus ring that is separated into a plurality of parts and assembled, thereby only the part of the combined focus ring that is exposed to plasma and consumed by etching can be replaced. Background Art

[0002] Generally, the etching technology used for manufacturing semiconductors is a technology for processing a film formed on a semiconductor substrate into a desired pattern, and the device used for such processing is an etching device.

[0003] In particular, among etching devices, an etching device that forms a pattern using plasma is called a plasma etching device or a dry etching device. Such a dry etching device is mainly used in a technology that requires a design rule of 0.15 μm or less.

[0004] Figure 1 A general dry etching apparatus is shown, wherein an electrostatic chuck 11 for placing a wafer W is provided inside a processing chamber 10 , a lower electrode 12 is provided on the bottom surface of the electrostatic chuck 11 , and an upper electrode 13 is provided at a predetermined height from the electrostatic chuck 11 .

[0005] Then, the reaction gas is supplied from the upper portion or one side of the processing chamber 10 including the upper electrode 13 .

[0006] Therefore, when the electrostatic chuck 11 of the processing chamber 10 is placed with the wafer W, a reaction gas is supplied to the inside and an RF bias is applied to the lower electrode 12 and the upper electrode 13, plasma is generated on the upper part of the wafer W, and the plasma collides with the film quality of the wafer W to etch it.

[0007] During the process of etching the wafer W using plasma, the outer side of the wafer W is usually surrounded by the edge ring 14 on the electrostatic chuck 11 , so that the plasma is evenly distributed to the edge ring 14 of the wafer W.

[0008] According to the structure of the focusing ring in the "focusing ring of a semiconductor wafer manufacturing device" of Korean Patent Publication No. 10-2005-0091853 (hereinafter referred to as "Patent Document 1"), the focusing ring is divided into an outer ring and an inner ring, and the outer ring and the inner ring are separated in a vertical form to each other, and the wafer only contacts the upper end of the inner ring.

[0009] In addition, the outer ring is located outside with the wafer as the center and is in contact with and coupled to the inner side of the inner cover ring, and the inner ring is coupled to the inner side of the outer ring.

[0010] In the case of the focusing ring of the previous patent document 1, the outer ring and the inner ring are separated and assembled in the vertical direction, so that a gap occurs in the separated and assembled portion, and a difference in temperature transfer rate occurs between the inner and outer sides through the gap. When the polymer is coated through the gap between the outer ring and the inner ring, there is a problem of arcing.

[0011] In addition, a potential difference of plasma occurs due to the gap separating the outer ring and the inner ring, and thus a problem occurs in wafer edge yield due to a change in the plasma sheath. Summary of the invention

[0012] Technical issues

[0013] Therefore, the present invention has been developed to solve the above-mentioned problems, and its purpose is to provide a combined focusing ring as follows: the focusing ring is separated into multiple parts in the upper and lower horizontal directions and assembled, so that only the upper plasma exposed part can be replaced, and each focusing ring can be manufactured from the same material or a mixture of different materials, thereby saving operating efficiency and costs.

[0014] Solution to the problem

[0015] In order to achieve the above-mentioned purpose, the combined focusing ring of an embodiment of the present invention includes: an upper plasma exposure ring, which is placed on the upper outer side of the electrostatic suction cup; a lower thermally conductive support ring, which is assembled to be tightly attached to the lower part of the above-mentioned upper plasma exposure ring; a combining ring, which is assembled to the outer side of the above-mentioned lower thermally conductive support ring; a first combining portion, which combines the above-mentioned upper plasma exposure ring and the lower thermally conductive support ring; and a second combining portion, which combines the above-mentioned upper plasma exposure ring and the combining ring.

[0016] The above-mentioned first connecting part includes: a first group of connecting pieces, which are formed on the outside of the inner surface of the upper plasma exposed ring; and a second group of connecting pieces, which are formed on the outer side surface of the upper end of the above-mentioned lower thermal conductive support ring, and are combined with the first group of connecting pieces to combine the upper plasma exposed ring and the lower thermal conductive support ring.

[0017] The first set of connecting pieces is formed on the outer side surface of the lower part of the upper plasma exposed ring, and the second set of connecting pieces is formed on the inner side surface of the upper end of the lower heat conductive support ring and is assembled with the first set of connecting pieces.

[0018] The second coupling portion includes a first coupling tab formed outside the outer surface of the upper plasma exposed ring and a second coupling tab formed inside the upper portion of the coupling ring and coupled with the first coupling tab to couple the upper plasma exposed ring and the coupling ring.

[0019] The combined focus ring further includes a step portion formed on the lower heat conductive support ring and the combined ring to improve the close contact efficiency when the lower heat conductive support ring and the combined ring are assembled.

[0020] The stepped portion includes an upper step formed on the upper outer side of the lower heat-conducting support ring and a lower step formed on the inner upper part of the coupling ring and in close contact with the upper step.

[0021] The combined focusing ring further comprises a heat conducting sheet, which is arranged between the upper plasma exposure ring and the lower heat conducting support ring to improve the thermal conductivity.

[0022] The thermally conductive sheet is made of silicon and contains aluminum oxide or silicon carbide (SiC) as an additive having high thermal conductivity.

[0023] A bolt connection groove is formed at the lower portion of the upper plasma exposure ring, and an insertion groove is formed vertically through the lower heat conductive support ring in communication with the bolt connection groove, so that connection bolts are connected to the insertion groove and the bolt connection groove.

[0024] Effects of the Invention

[0025] As described above, according to the combined focusing ring of the present invention, the focusing ring is divided into multiple parts in the upper and lower horizontal directions, and the upper plasma exposed ring and the lower thermal conductive support ring are assembled by screws through the first combining part, thereby making the inner and outer sides of the upper plasma exposed ring and the lower thermal conductive support ring evenly close to each other, and close to the combined ring at the bottom of the lower thermal conductive support ring, thereby assembling it with the upper plasma exposed ring by screws through the second combining part, so that the upper plasma exposed ring and the lower thermal conductive support ring are close to each other to the maximum extent without any gap, thereby causing no difference in temperature transfer rate and maximizing product performance.

[0026] In addition, the present invention divides the focusing ring into multiple parts that can be assembled and disassembled, so that the upper plasma exposure ring and the lower heat conductive support ring have different lifespans and different replacement cycles, thereby reducing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a side cross-sectional view showing a general etching device.

[0028] Figure 2 It is an exploded perspective view showing the combined focus ring of the present invention.

[0029] Figure 3 It is a combined stereoscopic view showing the combined focus ring of the present invention.

[0030] Figure 4 1 is a cross-sectional view showing a combined focus ring according to the present invention.

[0031] Figure 5 It is shown Figure 4 A cross-sectional view of a combined focusing ring before being combined.

[0032] Figure 6 is a cross-sectional view showing another assembled state of the combined focus ring of the present invention.

[0033] Figure 7 It is a cross-sectional view showing still another assembled state of the combined focus ring of the present invention.

[0034] Figure 8 This is an exploded perspective view showing another example of the combined focus ring of the present invention.

[0035] Fig. 9 It is shown Figure 8 A cross-sectional view of a combined focusing ring.

[0036] <Description of Symbols for Main Parts in the Drawings>

[0037] 100: Combined focus ring 110: Upper plasma exposure ring

[0038] 111: Bolt connection groove 120: Lower heat conduction support ring

[0039] 121: Insertion groove 130: Coupling ring

[0040] 140: first joint portion 141: first assembly joint piece

[0041] 142: second assembly of splices 150: second joint portion

[0042] 151: first connecting tab 152: second connecting tab

[0043] 160: Step 161: Upper step

[0044] 162: Lower step 200: Heat conducting sheet

[0045] B: Connecting bolt DETAILED DESCRIPTION

[0046] The present invention can be modified in various ways and can have various embodiments. Specific embodiments are illustrated in the drawings and described in detail in the embodiments. However, this does not limit the specific embodiments of the present invention. The present invention includes all changes, equivalents and substitutes within the scope of the concept and technology of the present invention.

[0047] In the accompanying drawings, the embodiments of the present invention are not limited to the specific forms shown in the drawings, and are sometimes enlarged and illustrated for clarity of description. Specific terms are used in this specification, but they are used to illustrate the present invention, and are not used to limit the meaning or the scope of rights of the present invention recorded in the claims.

[0048] In this specification, expressions such as 'and / or' indicate that at least one of the components arranged in front and behind is included. In addition, expressions such as 'connected / combined' include direct connection with other components or indirect connection through other components. In this specification, expressions in the singular include the meaning of the plural unless otherwise specified. In addition, components, steps, actions and elements described in the specification as 'including' or 'having' indicate that one or more other components, steps, actions and elements may exist or be added.

[0049] In addition, terms such as 'first', 'second', etc. are only used to distinguish multiple structures, and do not limit the order or other characteristics between the structures.

[0050] In the description of the embodiments, when each layer (film), region, pattern or structure is described as being formed "on" or "under" a substrate, each side (film), region, pad or pattern, it includes the case where it is formed directly or sandwiched with other layers. The reference of the above or below of each layer is described with reference to the figure.

[0051] Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

[0052] Figure 2 is an exploded perspective view showing the combined focus ring of the present invention, Figure 3 is a combined stereogram showing the combined focusing ring of the present invention, Figure 4 is a cross-sectional view showing a combined focus ring of the present invention, Figure 5 It is shown Figure 4 A cross-sectional view of a combined focusing ring before being combined. Figure 6 is a cross-sectional view showing another assembled state of the combined focus ring of the present invention, Figure 7 is a cross-sectional view showing another assembled state of the combined focus ring of the present invention, Figure 8 is a separated stereogram showing another example of the combined focus ring of the present invention, Fig. 9 It is shown Figure 8 A cross-sectional view of a combined focusing ring.

[0053] like Figures 2 to 7As shown, the combined focus ring 100 of the present invention includes an upper plasma exposed ring 110 , a lower heat conductive support ring 120 , a combining ring 130 , a first combining portion 140 and a second combining portion 150 .

[0054] The upper plasma exposure ring 110 is placed on the outer side of the upper portion of an electrostatic chuck (not shown) of a semiconductor etching apparatus.

[0055] The upper plasma exposure ring 110 is made of at least one of silicon, silicon carbide (SiC), boron carbide (B4C), silicon dioxide (SiO2) and aluminum oxide.

[0056] The lower heat conductive support ring 120 is processed separately from the upper plasma exposed ring 110 and is assembled by being closely attached to the lower portion of the upper plasma exposed ring 110 .

[0057] The lower heat conductive support ring 120 is made of at least one of silicon, silicon carbide (SiC), boron carbide (B4C), silicon dioxide (SiO2), aluminum oxide (Al2O3), and aluminum oxide.

[0058] The coupling ring 130 is closely attached to the outer side of the lower heat conductive support ring 120 and coupled to the upper plasma exposed ring 110 .

[0059] The coupling ring 130 is made of at least one of silicon, silicon carbide (SiC), boron carbide (B4C), silicon dioxide (SiO2), aluminum oxide (Al2O3), and aluminum oxide.

[0060] The first coupling portion 140 is provided on the upper plasma exposed ring 110 and the lower thermal conductive support ring 120 to detachably couple the upper plasma exposed ring 110 and the lower thermal conductive support ring 120 .

[0061] In addition, the first coupling portion 140 couples the lower thermally conductive support ring 120 to the lower portion of the upper plasma exposed ring 110 , so that the upper plasma exposed ring 110 and the lower thermally conductive support ring 120 are evenly and tightly attached to the inner side and the outer side.

[0062] like Figures 4 to 5 As shown, the first combining portion 140 includes a first set of connecting pieces 141 and a second set of connecting pieces 142 .

[0063] The first set of splice pieces 141 are formed on the outer side of the inner surface of the upper plasma exposed ring 110 .

[0064] In addition, the first assembly of connecting pieces 141 is formed with threads, preferably formed with internal threads, so as to screw-assemble the upper plasma exposed ring 110 and the lower heat conductive support ring 120 .

[0065] The second set of connecting pieces 142 are formed on the outer side surface of the upper end of the lower heat conductive support ring 120 .

[0066] In addition, the second set of connecting pieces 142 is formed with threads, preferably formed with external threads, so as to be combined with the first set of connecting pieces 141 to combine the upper plasma exposed ring 110 and the lower thermal conductive support ring 120 .

[0067] That is, the first assembly connecting piece 141 and the second assembly connecting piece 142 are formed into internal threads and external threads and are screwed together.

[0068] As an example, Figure 6 As shown, the first set of connecting pieces 141 is formed on the outer side surface of the lower portion of the upper plasma exposed ring 110 , and the second set of connecting pieces 142 is formed on the inner side surface of the upper end of the lower heat conductive support ring 120 and connected to the first set of connecting pieces 141 .

[0069] At this time, the first set of connecting pieces 141 is formed of external threads, and the second set of connecting pieces 142 is formed of internal threads, so that the upper plasma exposed ring 110 and the lower heat conductive support ring 120 are combined by screws.

[0070] The second coupling part 150 couples the upper plasma exposed ring 110 and the coupling ring 130 .

[0071] like Figures 4 to 7 As shown, the second connecting portion 150 includes a first connecting piece 151 and a second connecting piece 152 .

[0072] The above-mentioned first coupling tab 151 is formed on the outer side of the outer surface of the upper plasma exposed ring 110 .

[0073] In addition, the first coupling tab 151 is formed with a thread, preferably an external thread, so as to screw the upper plasma exposed ring 110 and the coupling ring 130 together when the upper plasma exposed ring 110 and the lower thermal conductive support ring 120 are assembled.

[0074] The second coupling tab 152 is formed on the inner side of the upper portion of the coupling ring 130 .

[0075] In addition, the second coupling tab 152 is formed with a thread, preferably an internal thread, to be combined with the first coupling tab 151 to combine the upper plasma exposed ring 110 and the coupling ring 130 .

[0076] That is, the first coupling tab 151 and the second coupling tab 152 are formed as internal threads and external threads to be screwed to each other.

[0077] The lower heat conductive support ring 120 and the coupling ring 130 are formed with a step portion 160 to improve the close contact efficiency between the lower heat conductive support ring 120 and the coupling ring 130 when the coupling ring 130 is coupled to the upper plasma exposed ring 110 in a state where the upper plasma exposed ring 110 and the lower heat conductive support ring 120 are coupled.

[0078] The stepped portion 160 includes an upper step 161 formed on the outer side of the upper portion of the lower heat conductive support ring 120 and a lower step 162 formed on the upper portion of the inner side of the coupling ring 130 and in close contact with the upper step 161 .

[0079] That is, the lower heat-conductive support ring 120 is separated from the lower part of the upper plasma exposed ring 110 in the horizontal direction, and in a state of being assembled by screws through the first coupling portion 140, when the coupling ring 130 is coupled to the upper plasma exposed ring 110 through the second coupling portion 150 on the outer side surface of the lower heat-conductive support ring 120, the contact portion between the upper plasma exposed ring 110 and the lower heat-conductive support ring 120 is firmly and tightly attached without a gap through the step portion 160.

[0080] like Figure 7 As shown, the upper plasma exposed ring 110 and the lower heat conductive support ring 120 are connected by connecting bolts B.

[0081] The upper plasma exposed ring 110 is formed with a bolt coupling groove 111 at a lower portion thereof to be coupled with a coupling bolt B.

[0082] In addition, an insertion groove 121 is formed in the lower heat transfer support ring 120 to penetrate vertically so as to communicate with the bolt connection groove 111 , and the connection bolt B is inserted through the insertion groove 121 and connected to the bolt connection groove 111 .

[0083] like Figures 8 to 9 As shown, a heat conductive sheet 200 is inserted between the upper plasma exposed ring 110 and the lower heat conductive support ring 120 to improve thermal conductivity.

[0084] The thermally conductive sheet 200 is made of silicon and may contain aluminum oxide or silicon carbide (SiC) as an additive having high thermal conductivity.

[0085] The combined focus ring of the present invention having the above-mentioned structure operates as follows.

[0086] The combined focus ring 100 is not processed using one workpiece, but is divided into a plurality of workpieces, namely, the upper plasma exposed ring 110 and the lower heat conductive support ring 120, and each is processed separately.

[0087] Furthermore, the lower heat conductive support ring 120 is separated from the lower portion of the upper plasma exposed ring 110 in a horizontal direction, and the first assembly connecting piece 141 and the second assembly connecting piece 142 are screwed together, thereby assembling the upper plasma exposed ring 110 and the lower heat conductive support ring 120.

[0088] In this way, the upper plasma exposed ring 110 and the lower heat conductive support ring 120 are separated and horizontally arranged in an upper and lower position, and are threadedly coupled together through the first coupling portion 140, so that the upper plasma exposed ring 110 and the lower heat conductive support ring 120 are tightly attached as firmly and evenly as possible, thereby causing no gap to occur on the inner or outer sides of the upper plasma exposed ring 110 and the lower heat conductive support ring 120.

[0089] In addition, the upper plasma exposure ring 110 and the lower heat conductive support ring 120 are separated and assembled, so when an abnormality occurs in any part, there is no need to replace the entire combined focusing ring 100. The upper plasma exposure ring 110 and the lower heat conductive support ring 120 can be separated and only the upper plasma exposure part can be replaced.

[0090] Therefore, the upper plasma exposed ring 110 and the lower heat conductive support ring 120 have different lifespans and thus different replacement cycles, thereby saving replacement costs.

[0091] Furthermore, the upper plasma exposed ring 110 and the lower heat conductive support ring 120 are assembled via the first coupling portion 140, and the coupling ring 130 is assembled with the upper plasma exposed ring 110 via the second coupling portion 150, so that the contact portions of the upper plasma exposed ring 110 and the lower heat conductive support ring 120 are firmly attached to each other without any gap, thereby maintaining a uniform temperature of the plasma heat transferred to the plasma exposed surface in the lower heat conductive support ring, thereby preventing process variations.

[0092] As described above, the present invention is not limited to the above-mentioned specific preferred embodiments, and those skilled in the art can make various modifications without departing from the gist of the present invention as claimed in the claims, and the equivalent changes are included in the scope of the claims.

Claims

1. A combined focusing ring, characterized in that: It includes: an upper plasma exposure ring disposed on an upper outer side of the electrostatic chuck; A lower heat-conducting support ring, which is assembled to fit closely to the lower portion of the upper plasma-exposed ring; A coupling ring assembled to the outer side of the lower heat-conducting support ring; A first joint portion that joins the upper plasma exposed ring and the lower thermal conductive support ring; and a second bonding portion bonding the upper plasma exposed ring and the bonding ring; The upper plasma exposed ring and the lower heat conductive support ring are combined in a manner having a horizontal contact surface. The first joint portion combines the upper plasma exposed ring and the lower heat conductive support ring through the first set of joint pieces and the second set of joint pieces, and they are respectively formed into internal threads and external threads to be combined in a screw manner. The second coupling portion includes: a first coupling tab formed on the outer side of the outer surface of the upper plasma exposed ring; and a second coupling tab formed on the upper inner side of the coupling ring and coupled with the first coupling tab to couple the upper plasma exposed ring and the coupling ring. The combined focusing ring further includes a step portion, which is formed on the lower heat-conducting support ring and the combined ring to improve the close contact efficiency when the lower heat-conducting support ring and the combined ring are assembled. The step portion includes: an upper step formed on the upper outer side of the lower heat-conducting support ring; and a lower step formed on the inner upper part of the coupling ring and in close contact with the upper step. The combined focusing ring further includes a heat conductive sheet disposed between the upper plasma exposed ring and the lower heat conductive support ring to improve thermal conductivity, wherein the heat conductive sheet is made of silicon and further includes aluminum oxide or silicon carbide (SiC) as an additive with high thermal conductivity.

2. The combined focus ring according to claim 1, characterized in that: The first assembly of the first joint portion is formed on the outer side of the inner surface of the upper plasma exposed ring. The second set of connecting pieces is formed on the outer side surface of the upper end of the lower heat-conducting supporting ring.

3. The combined focus ring according to claim 1, characterized in that: The first assembly of the first joint portion is formed on the outer side surface of the lower portion of the upper plasma exposed ring. The second set of connecting pieces is formed on the inner side surface of the upper end of the lower heat-conducting supporting ring.

4. The combined focus ring according to claim 1, characterized in that: A bolt connection groove is formed at the lower portion of the upper plasma exposure ring, and an insertion groove is formed vertically through the lower heat conductive support ring in communication with the bolt connection groove, so that connection bolts are connected to the insertion groove and the bolt connection groove.

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