PECVD (plasma enhanced chemical vapor deposition) lower electrode
By employing a beveled sealing structure in the electrode during PECVD, the problem of insufficient sealing performance was solved, achieving better airtightness and electromagnetic shielding, and preventing gas leakage.
Patent Information
- Application Number
- CN202511829944.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-05
- Publication Date
- 2026-02-24
AI Technical Summary
The sealing performance of the lower electrode in existing PECVD equipment is insufficient, leading to gas leakage problems.
The sealing structure, featuring a beveled design, includes a bottom block, a first spacer block, and a sealing ring. The beveled connection and compression achieve a tight fit of the sealing ring, which is further enhanced by the fixing seat and bolts.
It effectively prevents gas leakage through the gaps between the heating tube sleeve, the ceramic barrel and the bottom block, and the spacer block, thus improving the airtightness and electromagnetic shielding performance of the equipment.
Smart Images
Figure CN121556006A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of semiconductor equipment technology, and specifically relates to a PECVD lower electrode. Background Technology
[0002] PECVD (Plasma Enhanced Chemical Vapor Deposition) is a technology that uses radio frequency or microwave energy to ionize reactive gases, forming a thin film deposited by reacting active particles with a substrate surface. It is primarily used in the manufacturing of semiconductors, photovoltaics, display panels, and high-end electronic devices. The reaction chamber contains two electrode systems, upper and lower, connected to ground and a radio frequency source respectively, thereby ionizing the reactive gases input into the chamber. To prevent leakage, the entire chamber, as well as any mechanisms extending into it, must be sealed.
[0003] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention
[0004] The purpose of this invention is to provide a lower electrode for PECVD that has excellent sealing performance.
[0005] To achieve the above objectives, a specific embodiment of the present invention provides a PECVD lower electrode, comprising an electrode plate, a ceramic barrel, a heating tube sleeve, and a sealing structure. The ceramic barrel is connected to the electrode plate; the heating tube sleeve is connected to the electrode plate and passes through the ceramic barrel, with one end protruding from the ceramic barrel; the sealing structure is connected to the heating tube sleeve and the ceramic barrel, comprising a bottom block, a first spacer block, and a first sealing ring. The bottom block is fitted onto both the heating tube sleeve and the ceramic barrel. The first spacer block is fitted onto the outside of the ceramic barrel and abuts against the top surface of the bottom block. The top surface and the inner wall of the bottom block are connected by a first inclined surface. The first sealing ring is simultaneously pressed between the ceramic barrel, the first inclined surface, and the first spacer block.
[0006] In one or more embodiments of the present invention, the sealing structure further includes a fixing seat fitted onto the ceramic barrel, a limiting ring is recessed on the outer wall of the ceramic barrel, the fixing seat is embedded in the limiting ring, and the first spacer block is pressed between the fixing seat and the bottom block.
[0007] In one or more embodiments of the present invention, a retaining ring protrudes from the top edge of the bottom block, and the first spacer block and the fixing seat abut against the retaining ring.
[0008] In one or more embodiments of the present invention, the sealing structure further includes a second spacer block sleeved on the ceramic barrel, the second spacer block abutting against the fixing seat, and the second spacer block being fixed to the fixing seat, the first spacer block and the bottom block by bolts.
[0009] In one or more embodiments of the present invention, a radio frequency shielding induction plate is also sleeved on the heating tube sleeve, the radio frequency shielding induction plate is located below the bottom block, and is fixed to the bottom block by bolts.
[0010] In one or more embodiments of the present invention, a shaft sealing gasket is pressed between the radio frequency shielding induction plate and the bottom block.
[0011] In one or more embodiments of the present invention, a second sealing ring is pressed between the shaft sealing gasket and the bottom block.
[0012] In one or more embodiments of the present invention, the bottom surface of the bottom block is connected to the inner wall by a second inclined surface, the shaft sealing gasket abuts against the bottom surface of the bottom block, and the second sealing ring is pressed between the second inclined surface, the inner wall of the heating tube sleeve, and the shaft sealing gasket.
[0013] In one or more embodiments of the present invention, a third sealing ring is pressed between the radio frequency shielding induction plate and the shaft sealing gasket.
[0014] In one or more embodiments of the present invention, the top surface of the radio frequency shielding induction plate is connected to the inner wall by a third inclined surface, and the third sealing ring is pressed between the heating tube sleeve, the third inclined surface and the shaft sealing gasket.
[0015] Compared with the prior art, the present invention provides better sealing performance by setting an inclined surface on the bottom block, so that when the sealing ring is compressed, the bottom block and the first spacer block can fit together and simultaneously fit into the ceramic barrel, thereby preventing the gas above from flowing out through the gap between the heating tube sleeve, the ceramic barrel and the bottom block and the first spacer block. Attached Figure Description
[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 This is a schematic diagram of PECVD in one embodiment of the present invention;
[0018] Figure 2This is a cross-sectional view of PECVD in one embodiment of the present invention;
[0019] Figure 3 for Figure 2 A magnified view of a portion of the image;
[0020] Figure 4 After removing the sealing ring and shielding ring Figure 2 A magnified view of a portion of the image.
[0021] Explanation of key figure labels:
[0022] 100-PECVD lower electrode, 10-electrode plate, 20-ceramic barrel, 30-heating tube sleeve, 40-sealing mechanism, 41-bottom block, 411-first inclined surface, 412-second inclined surface, 413-annular groove, 42-first spacer block, 431-first sealing ring, 432-second sealing ring, 433-third sealing ring, 44-fixed seat, 45-second spacer block, 46-RF shielding induction plate, 461-third inclined surface, 47-shaft sealing gasket, 48-shielding ring. Detailed Implementation
[0023] To enable those skilled in the art to better understand the technical solutions in this disclosure, the technical solutions in the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this disclosure.
[0024] like Figure 1 As shown, in one embodiment of the present invention, the PECVD lower electrode 100 includes an electrode plate 10, a ceramic barrel 20, a heating tube sleeve 30, and a sealing mechanism 40. The ceramic barrel 20 is connected to the electrode plate 10, and the heating tube sleeve 30 is connected to the electrode plate 10 and passes through the ceramic barrel 20, with one end protruding from the ceramic barrel 20. The sealing structure 40 is connected to the heating tube sleeve 30 and the ceramic barrel 20 to prevent gas leakage.
[0025] The ceramic barrel 20 supports the electrode 10, extending it into the reaction chamber of the PECVD equipment, and also acts as a physical barrier to prevent leakage of radio frequency electromagnetic waves. Although the reaction temperature of the PECVD equipment is relatively low, the electrode 10 still needs to be heated by the heating tube sleeve 30 connected to an external heat source. In addition to the PECVD lower electrode 100, there is also an upper electrode in the reaction chamber. The lower electrode 100 is grounded, and the upper electrode is connected to the radio frequency source. The input process gas is ionized into an ionized state and deposited on the substrate surface.
[0026] To prevent gas leakage, the lower electrode 100 needs to be sealed using a sealing structure 40. Specifically, the sealing structure 40 includes a bottom block 41, a first spacer block 42, and a first sealing ring 431. The bottom block 41 is a sleeve structure with two openings, and the two inner walls are respectively fitted onto the heating tube sleeve 30 and the ceramic barrel 20. The annular first spacer block 42 is fitted onto the ceramic barrel 20 and abuts against the top surface of the bottom block 41. The top surface and inner wall of the bottom block 41 are connected by a first inclined surface 411, and the first sealing ring 431 is simultaneously pressed between the ceramic barrel 20, the first inclined surface 411, and the first spacer block 42. A triangular-shaped annular groove is formed between the first inclined surface 411, the outer wall of the ceramic barrel 20, and the bottom wall of the first spacer block 42. This annular groove provides a space for the first sealing ring 431, so that when the first sealing ring 431 is compressed, the bottom block 41 and the first spacer block 42 can fit together and simultaneously fit into the ceramic barrel 20. Therefore, it can provide better sealing performance and prevent the gas above from flowing out through the gap between the heating tube sleeve 30, the ceramic barrel 20, the bottom block 41, and the first spacer block 42.
[0027] To improve the stability of the first spacer block 42 on the ceramic barrel 20 and prevent it from moving along the outer wall of the ceramic barrel 20, the sealing structure 40 also includes a fixing seat 44 sleeved on the ceramic barrel 20. A limiting ring 21 is recessed on the outer wall of the ceramic barrel 20, the width of which is approximately equal to the width of the fixing seat 44. The fixing seat 44 is embedded within the limiting ring 21, and the first spacer block 42 is pressed between the fixing seat 44 and the bottom block 41. The fixing seat 44 is a circular structure composed of two semi-circular rings. After being embedded in the limiting ring 21, it cannot move. It and the bottom block 41 provide support for the first spacer block 42 at its upper and lower ends, respectively. The first spacer block 42 is pressed between the bottom block 41 and the fixing seat 44 and cannot move.
[0028] To further improve the stability of the fixing seat 44 and the first spacer block 42, a retaining ring 411 protrudes from the top edge of the bottom block 41. The protrusion height of the retaining ring 411 is greater than the thickness of the first spacer block 42, so that the first spacer block 42 as a whole, and at least part of the fixing seat 44, abut against the retaining ring 411. The fixing seat 44 will not be accidentally opened, and the stability is high.
[0029] In such Figure 3In the illustrated embodiment, the sealing structure 40 further includes a second spacer 45 fitted onto the ceramic barrel 20. The second spacer 45 is an annular structure disposed above the fixing seat 44, abutting against the fixing seat 44, and fixed to the fixing seat 44, the first spacer 42, and the bottom block 41 by bolts. For example, the second spacer 45, the fixing seat 44, the first spacer 42, and the bottom block 41 can have the same number of corresponding mounting holes (not shown in the figure), wherein at least the mounting holes on the bottom block 41 are threaded holes, and the mounting holes on the other components can be threaded holes or smooth through holes. During installation, the second spacer 45, the fixing seat 44, the first spacer 42, and the bottom block 41 are rotated until all mounting holes are coaxial, and bolts are screwed in to achieve fixation.
[0030] In one embodiment, to further prevent electromagnetic waves from leaking downwards along the heating tube sleeve 30, an RF shielding induction plate 46 is also sleeved on the heating tube sleeve 30. This plate is located below the bottom block 41 and is fixed to the bottom block 41 by bolts. For example, mounting holes (not shown) are provided on both the bottom block 41 and the RF shielding induction plate 46. The number of holes is the same and their positions correspond. At least the mounting holes on the bottom block 41 are threaded holes, while the mounting holes on the RF shielding induction plate 46 are either threaded holes or smooth through holes. After rotating both plates until their mounting holes are coaxial, bolts are inserted for fixation.
[0031] Preferably, a shaft sealing gasket 47 is pressed between the radio frequency shielding induction plate 46 and the bottom block 41 to improve structural stability.
[0032] Furthermore, a second sealing ring 432 is squeezed between the shaft sealing gasket 47 and the bottom block 41 to further improve airtightness and prevent gas in the cavity from flowing out from the gap between the heating tube sleeve 30 and the bottom block 41 and the shaft sealing gasket 47.
[0033] like Figure 3 , 4 As shown, the bottom surface of the bottom block 41 is connected to the inner wall via a second inclined surface 412. This second inclined surface 412 forms a triangular annular groove with the inner wall of the heating tube sleeve 30 and the shaft sealing gasket 47. The second sealing ring 432 is disposed in this annular groove. This annular groove allows the shaft sealing gasket 47 and the bottom block 41 to still abut against each other and adhere to the heating tube sleeve 30 when the second sealing ring 432 is compressed, thus preventing the formation of gaps and gas leakage.
[0034] Furthermore, a third sealing ring 433 is pressed between the radio frequency shielding induction plate 46 and the shaft sealing gasket plate 47 to improve airtightness.
[0035] Furthermore, the top surface of the RF shielding induction plate 46 is connected to the inner wall via a third inclined surface 461. This third inclined surface 461, together with the heating tube sleeve 30 and the shaft sealing gasket 47, forms a triangular-shaped annular groove, within which the third sealing ring 433 is pressed. This annular groove also ensures that when the third sealing ring 433 is compressed, the shaft sealing gasket 47 and the RF shielding induction plate 46 are in close contact with each other, and simultaneously with the heating tube sleeve 30, preventing gaps, improving airtightness, and preventing gas leakage.
[0036] An annular groove 413 is provided on the bottom surface of the bottom block 41, and a shielding ring 48 is provided in the annular groove 413. The shielding ring 48 is pressed between the bottom block 41 and the shaft sealing gasket 47 to further improve the electromagnetic shielding performance.
[0037] It will be apparent to those skilled in the art that this disclosure is not limited to the details of the exemplary embodiments described above, and that this disclosure can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of this disclosure is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this disclosure. No reference numerals in the claims should be construed as limiting the scope of the claims.
[0038] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.
Claims
1. An electrode for PECVD, characterized in that, include: Electrode plates; A ceramic barrel, connected to the electrode plate; A heating tube sleeve is connected to the electrode plate and passes through the ceramic barrel, with one end protruding from the ceramic barrel; A sealing structure, connected to the heating tube sleeve and the ceramic barrel, includes a bottom block, a first spacer block, and a first sealing ring. The bottom block is fitted onto both the heating tube sleeve and the ceramic barrel. The first spacer block is fitted onto the outside of the ceramic barrel and abuts against the top surface of the bottom block. The top surface of the bottom block and its inner wall are connected by a first inclined surface. The first sealing ring is simultaneously pressed between the ceramic barrel, the first inclined surface, and the first spacer block.
2. The PECVD lower electrode according to claim 1, characterized in that, The sealing structure also includes a fixing seat fitted onto the ceramic barrel. A limiting ring is recessed on the outer wall of the ceramic barrel, and the fixing seat is embedded in the limiting ring. The first spacer block is pressed between the fixing seat and the bottom block.
3. The PECVD lower electrode according to claim 2, characterized in that, A retaining ring protrudes from the top edge of the bottom block, and the first spacer block and the fixing seat abut against the retaining ring.
4. The PECVD lower electrode according to claim 3, characterized in that, The sealing structure also includes a second spacer block fitted onto the ceramic barrel, the second spacer block abutting against the fixed seat, and the second spacer block being fixed to the fixed seat, the first spacer block, and the bottom block by bolts.
5. The PECVD lower electrode according to claim 1, characterized in that, An RF shielding induction plate is also fitted onto the heating tube sleeve. The RF shielding induction plate is located below the bottom block and is fixed to the bottom block by bolts.
6. The PECVD lower electrode according to claim 5, characterized in that, A shaft sealing gasket is pressed between the radio frequency shielding induction plate and the bottom block.
7. The PECVD lower electrode according to claim 6, characterized in that, A second sealing ring is pressed between the shaft sealing gasket and the bottom block.
8. The PECVD lower electrode according to claim 7, characterized in that, The bottom surface of the bottom block is connected to the inner wall by a second inclined surface. The shaft sealing gasket abuts against the bottom surface of the bottom block, and the second sealing ring is pressed between the second inclined surface, the inner wall of the heating tube sleeve, and the shaft sealing gasket.
9. The PECVD lower electrode according to claim 6, characterized in that, A third sealing ring is pressed between the radio frequency shielding induction plate and the shaft sealing gasket.
10. The PECVD lower electrode according to claim 9, characterized in that, The top surface of the radio frequency shielding induction plate is connected to the inner wall by a third inclined surface, and the third sealing ring is pressed between the heating tube sleeve, the third inclined surface and the shaft sealing gasket.