Internal and external composite ceramic ring and graphite boat
Through the internal and external composite ceramic ring structure, the deposition of conductive film on the surface of the inner ceramic ring is delayed, and the problem of degradation of the insulation performance of the ceramic ring is solved, and the use cycle of the ceramic ring is extended and the product quality is improved.
Patent Information
- Application Number
- CN202422659842.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-31
- Publication Date
- 2025-08-29
- Estimated Expiration
- 2034-10-31
AI Technical Summary
In the prior art, the ceramic ring is degraded during use due to the deposition of conductive films, which in turn causes conduction between the positive and negative plates of the graphite boat, resulting in a decrease in product quality, a decrease in yield and an increase in rework rate.
The inner and outer composite ceramic ring structure is adopted. The outer ceramic ring and the inner ceramic ring are coaxially set and connected through the connecting ring to form an annular cavity. The outer ceramic ring protects the inner ceramic ring, prevents the conductive film from being deposited on the surface of the inner ceramic ring, and insulating is achieved through contact with the graphite boat sheet.
The insulation usage cycle of ceramic ring is extended, prevents the conduction between the positive and negative plates of the graphite boat, improves product quality and yield, reduces the rework rate, reduces the time and cost of replacing ceramic rings, shortens the production cycle, and reduces production costs.
Smart Images
Figure CN223280937U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of graphite boats, and particularly relates to an inner and outer composite ceramic ring and a graphite boat utilizing the inner and outer composite ceramic ring. Background Art
[0002] Tubular PECVD equipment is now widely used in coating process production. The equipment usually uses a graphite boat as a material carrier. After connecting to a pulse power supply and introducing reactive gas, it can coat the material surface under corresponding process conditions.
[0003] Graphite boats typically use ceramic rods as supports, which are then mounted with ceramic rings for electrical insulation, isolating the adjacent positive and negative plates of the graphite boat. When using PECVD to deposit a good conductor film such as doped amorphous silicon, a conductive film is deposited on the ceramic rings. This thin film accumulates over time and with repeated use, gradually degrading the insulating properties of the rings. Eventually, the rings become conductive, allowing conduction between the positive and negative plates of the graphite boat. This can lead to process instability, resulting in reduced product quality, lower yields, and increased rework rates. Utility Model Content
[0004] The embodiment of the present utility model provides an inner and outer composite ceramic ring and a graphite boat, which aims to delay the time of depositing a conductive film on the ceramic ring, extend the service life of the ceramic ring insulation, and prevent conduction between the positive and negative plates of the graphite boat, which would cause a decline in product quality, a decrease in yield, and an increase in rework rate.
[0005] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: to provide an inner and outer composite ceramic ring, comprising: an inner ceramic ring, an outer ceramic ring and a connecting ring, which are coaxially sleeved on the outside of the inner ceramic ring, and an annular cavity is formed between the outer ceramic ring and the inner ceramic ring; the axial length of the inner ceramic ring is greater than the axial length of the outer ceramic ring, and both axial ends of the inner ceramic ring protrude from the outside of the outer ceramic ring, so that the axial ends of the inner ceramic ring are in contact with the surface of the graphite boat; the connecting ring is arranged in the annular cavity to connect the inner ceramic ring and the outer ceramic ring together.
[0006] In combination with the first aspect, in one achievable manner, the connecting ring divides the annular cavity into two non-connected annular grooves.
[0007] In combination with the first aspect, in one achievable manner, an uneven rough structure is provided on the outer surface of the inner ceramic ring.
[0008] In combination with the first aspect, in one achievable manner, the rough structure includes protrusions uniformly distributed on the outer surface of the inner ceramic ring, and the shape of the protrusions is any one of a polygonal pyramid, a polygonal pyramid, and a spherical cap.
[0009] In combination with the first aspect, in one achievable manner, the rough structure includes annular teeth formed on the outer surface of the inner ceramic ring and surrounding along the axis of the inner ceramic ring.
[0010] In combination with the first aspect, in one achievable manner, the shape of the annular teeth along the axial cross section of the inner ceramic ring is a triangle or a trapezoid.
[0011] In combination with the first aspect, in one achievable manner, the rough structure includes spiral protrusions spirally formed on the outer surface of the inner ceramic ring.
[0012] In combination with the first aspect, in one achievable manner, the inner diameter D1 of the outer ceramic ring is greater than the outer diameter D2 of the inner ceramic ring, and the difference is 2-4 mm.
[0013] In combination with the first aspect, in one achievable manner, the axial length L1 of the outer ceramic ring is smaller than the axial length L2 of the inner ceramic ring, and the difference is 2-4 mm.
[0014] In a second aspect, an embodiment of the present invention further provides a graphite boat provided with the inner and outer composite ceramic rings.
[0015] The inner and outer composite ceramic rings and graphite boat provided by the present invention have the following beneficial effects compared with the prior art: the outer ceramic ring and the inner ceramic ring are coaxially sheathed to form an annular cavity between the two, and the outer ceramic ring and the inner ceramic ring are connected as a whole by a connecting ring. When an amorphous silicon conductive film is deposited on the silicon wafer in the graphite boat, the conductive film can be directly deposited on the surface of the outer ceramic ring; and since the overall size of the ceramic ring is relatively small, generally on the millimeter level, an annular cavity with a narrow gap is formed between the outer ceramic ring and the inner ceramic ring, and the reaction gas is blocked in the narrow gap, which is not conducive to the deposition of the conductive film on the outer surface of the inner ceramic ring, and is even more not conducive to the formation of a uniform conductive film on the outer surface of the inner ceramic ring, thereby protecting the inner ceramic ring through the outer ceramic ring and the two The annular cavity formed therebetween can delay the period of depositing a conductive film on the outer surface of the inner ceramic ring to form a conductor; and since the axial ends of the inner ceramic ring are in contact with the graphite boat, the axial ends of the outer ceramic ring will not contact the graphite boat due to the protrusions of the axial ends of the inner ceramic ring, and it is the inner ceramic ring that plays the role of insulation. Therefore, by delaying the time of depositing a conductive film on the outer surface of the inner ceramic ring to form a conductor, the effective insulation service life of the inner ceramic ring as an insulator can be extended, thereby preventing conduction between the positive and negative plates of the graphite boat, improving product quality and yield, and reducing the rework rate of product coating; at the same time, since the service life of the ceramic ring is extended, the time and cost of replacing the ceramic ring can also be reduced, which is also conducive to shortening the production cycle and reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 A schematic cross-sectional view of the inner and outer composite ceramic rings provided in an embodiment of the present invention;
[0017] Figure 2 for Figure 1 A schematic diagram of the side view structure of the inner and outer composite ceramic rings provided;
[0018] Description of reference numerals:
[0019] 1. Outer ceramic ring; 2. Connecting ring; 3. Rough structure; 4. Inner ceramic ring; 5. Annular groove. DETAILED DESCRIPTION
[0020] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.
[0021] Please also refer to Figure 1 and Figure 2 The inner and outer composite ceramic ring provided by the present invention is now described. The inner and outer composite ceramic ring comprises an inner ceramic ring 4, an outer ceramic ring 1, and a connecting ring 2, which are coaxially sleeved on the outer side of the inner ceramic ring 4, forming an annular cavity between the outer ceramic ring 1 and the inner ceramic ring 4. The axial length of the inner ceramic ring 4 is greater than the axial length of the outer ceramic ring 1, and both axial ends of the inner ceramic ring 4 protrude from the outer side of the outer ceramic ring 1, so that the axial ends of the inner ceramic ring 4 contact the surface of the graphite boat. The connecting ring 2 is disposed in the annular cavity to connect the inner ceramic ring 4 and the outer ceramic ring 1 together.
[0022] The inner and outer composite ceramic rings and graphite boat provided by the present invention have the following beneficial effects compared with the prior art: the outer ceramic ring 1 and the inner ceramic ring 4 are coaxially sheathed to form an annular cavity therebetween, and the outer ceramic ring 1 and the inner ceramic ring 4 are connected as a whole by using the connecting ring 2. When an amorphous silicon conductive film is deposited on the silicon wafer in the graphite boat, the conductive film can be directly deposited on the surface of the outer ceramic ring 1; and since the overall size of the ceramic ring is relatively small, generally on the millimeter level, an annular cavity with a narrow gap is formed between the outer ceramic ring 1 and the inner ceramic ring 4, and the reaction gas is blocked in the narrow gap, which is not conducive to the deposition of the conductive film on the outer surface of the inner ceramic ring 4, and is even more not conducive to the formation of a uniform conductive film on the outer surface of the inner ceramic ring 4, thereby forming a protective film on the inner ceramic ring 4 formed by the outer ceramic ring 1. The annular cavity formed therebetween can delay the period of depositing a conductive film on the outer surface of the inner ceramic ring 4 to form a conductor; and since the axial ends of the inner ceramic ring 4 are in contact with the graphite boat, the axial ends of the outer ceramic ring 1 will not contact the graphite boat due to the protrusions of the axial ends of the inner ceramic ring 4, and it is the inner ceramic ring 4 that plays the role of insulation. Therefore, by delaying the time of depositing a conductive film on the outer surface of the inner ceramic ring 4 to form a conductor, the effective insulation service life of the inner ceramic ring 4 as an insulator can be extended, thereby preventing conduction between the positive and negative plates of the graphite boat, improving the quality and yield of the product, and reducing the rework rate of the product coating; at the same time, since the service life of the ceramic ring is extended, the time and cost of replacing the ceramic ring can also be reduced, which is also conducive to shortening the production cycle and reducing production costs.
[0023] The connecting ring 2 is also made of ceramic and serves to connect the inner ceramic ring 4 and the outer ceramic ring 1, thereby enhancing the overall structural strength of the ceramic rings. Furthermore, it also serves as insulation between the inner ceramic ring 4 and the outer ceramic ring 1. In this application, the inner ceramic ring 4, the outer ceramic ring 1, and the connecting ring 2 are integrally formed, providing overall structural strength, reducing the risk of ceramic ring damage, increasing the service life of the ceramic rings, and reducing the failure rate of the graphite boat, thereby also contributing to improving the quality and yield of the coated products.
[0024] In some embodiments, as Figure 1 As shown, the connecting ring 2 divides the annular cavity into two disconnected annular grooves 5. Since the two annular grooves 5 are disconnected, airflow cannot circulate within the annular cavity, making it difficult for the reactant gas to enter the deep portion of the annular grooves 5. This prevents the deposition of a conductive film on the outer surface of the inner ceramic ring 4, or prolongs the time it takes for the conductive film deposited on the outer surface of the inner ceramic ring 4 to reach a uniform thickness sufficient to form a conductive layer. It also prolongs the time it takes for a uniformly thick conductive film to form a conductor on the outer surface of the inner ceramic ring 4.
[0025] It can be understood here that due to the existence of the annular groove 5 and the obstruction of the connecting ring 2, the reaction gas is not conducive to diffusing into the annular groove 5. Therefore, the thickness of the conductive film deposited on the outer part of the inner ceramic ring 4 will be faster than that in the deep part of the annular groove 5. Since the deposited conductive film needs to have a certain thickness to form a conductive layer that can conduct electricity; therefore, if the conductive layer is not formed in the deeper part of the annular groove 5, the inner ceramic ring 4 still has an insulating effect, and if the thickness of the conductive film on the surface of the inner ceramic ring 4 is uneven, the insulation performance of the inner ceramic ring 4 is still effective, thereby extending the time for forming the conductive layer on the outer surface of the inner ceramic ring 4, the insulation service life of the ceramic ring can be extended.
[0026] Preferably, the connecting ring 2 is arranged at the middle position of the axial length of the inner ceramic ring 4 and is radially connected to the inner wall of the outer ceramic ring 1 .
[0027] In some embodiments, as Figure 1 As shown, the outer surface of the inner ceramic ring 4 is provided with an uneven roughness 3. The uneven roughness 3 formed on the outer surface of the inner ceramic ring 4 can provide a certain barrier to the reaction gas, making it difficult to form a conductive film on the rough surface, and even more difficult to form a uniform conductive film on the rough surface. This can extend the time it takes for the conductive layer to form on the outer surface of the inner ceramic ring 4, thereby extending the insulation life of the ceramic ring and preventing two adjacent graphite boats from conducting and short-circuiting, which can cause failures and affect product quality and yield. If the insulation failure of the ceramic ring causes two adjacent graphite boats to conduct, this may result in an uneven amorphous silicon film deposited on the silicon wafer, resulting in substandard product quality after testing, necessitating rework and re-coating. This increases the rework rate of the silicon wafer coating and correspondingly increases production costs and production cycle.
[0028] In some embodiments, as Figure 1 As shown, the rough structure 3 includes protrusions evenly distributed on the outer surface of the inner ceramic ring 4, and the shape of the protrusions is any one of a polygonal pyramid, a polygonal cone, and a spherical cap. The protrusions formed on the outer surface of the inner ceramic ring 4 have a blocking effect on the reaction gas. Even if the reaction gas enters the annular groove 5, the reaction gas cannot be evenly deposited on the outer surface of the inner ceramic ring 4 due to the effect of the protrusions, thereby extending the time for the conductive layer to be formed on the outer surface of the inner ceramic ring 4 and improving the insulation service life of the ceramic ring. Among them, this application only lists some of the protrusion shapes, and the protrusions can also be other irregular shapes.
[0029] In some embodiments, as Figure 1As shown, the rough structure 3 includes annular teeth formed on the outer surface of the inner ceramic ring 4 and surrounding the axis of the inner ceramic ring 4. Based on the above analysis of the outer surface rough structure 3 of the inner ceramic ring 4 delaying the formation of the conductive layer, the annular teeth can also delay the period of forming the conductive layer on the outer surface of the inner ceramic ring 4. It should be noted that Figure 1 Provided is a schematic structural diagram of annular teeth formed on the outer surface of the inner ceramic ring 4.
[0030] In some embodiments, as Figure 1 As shown, the shape of the annular teeth along the axial cross section of the inner ceramic ring 4 is a triangle or a trapezoid, which can also extend the period of forming the conductive layer on the outer surface of the inner ceramic ring 4.
[0031] In some embodiments, as Figure 1 As shown, the rough structure 3 includes spiral protrusions spirally formed on the outer surface of the inner ceramic ring 4, which can also extend the period of forming the conductive layer on the outer surface of the inner ceramic ring 4. For example, the spiral protrusions can be a thread structure.
[0032] Alternatively, the rough structure 3 may be wavy patterns or patterns of other shapes provided on the outer surface of the inner ceramic ring 4, which may also make it difficult to form a conductive layer on the outer surface of the inner ceramic ring 4. If a conductive layer cannot be formed on the outer surface of the inner ceramic ring 4, no conductor capable of conducting a circuit will be formed.
[0033] In some embodiments, as Figure 1 As shown, the inner diameter D1 of the outer ceramic ring 1 is larger than the outer diameter D2 of the inner ceramic ring 4, with a difference of 2-4 mm. This indicates that the overall dimensions of the ceramic ring are relatively small, creating a narrow annular cavity that hinders the entry of reactive gases, thereby extending the period during which the conductive layer or film is formed on the outer surface of the inner ceramic ring 4. The difference between the outer ceramic ring 1 and the inner ceramic ring 4 is typically 3 mm.
[0034] In some embodiments, as Figure 1 As shown, the axial length L1 of the outer ceramic ring 1 is smaller than the axial length L2 of the inner ceramic ring 4, with a difference of 2-4 mm, typically 3 mm. The ends of the inner ceramic ring 4 typically extend beyond the ends of the outer ceramic ring 1 by 1-2 mm, preferably 1.5 mm. When the ends of the inner ceramic ring 4 abut the graphite boat, a 1.5 mm gap exists between the ends of the outer ceramic ring 1 and the graphite boat. This prevents electrical conduction between the graphite boats and does not affect the coating quality of the silicon wafer.
[0035] Since the outer ceramic ring 1 does not play a role in conduction and insulation, it only protects the inner ceramic ring 4, forms an annular cavity and delays the time of depositing a conductive film on the outer surface of the inner ceramic ring 4. Therefore, the outer surface of the outer ceramic ring 1 can be a smooth surface.
[0036] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant description of other embodiments.
[0037] Based on the same inventive concept, embodiments of the present application also provide a graphite boat equipped with the aforementioned inner and outer composite ceramic rings. Because the ceramic rings employed have a long insulation lifespan, the risk of conductive layer deposition on the outer surface of the inner ceramic ring 4 causing conduction in the graphite boat can be reduced, thereby improving product quality and yield, reducing the rework rate of coated products, and also reducing the time and expense of replacing the ceramic rings, thereby shortening production cycles and lowering production costs.
[0038] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.
Claims
1. An inner and outer composite ceramic ring, characterized in that: include: Inner ceramic ring (4); An outer ceramic ring (1) is coaxially sleeved on the outside of the inner ceramic ring (4), and an annular cavity is formed between the outer ceramic ring (1) and the inner ceramic ring (4); the axial length of the inner ceramic ring (4) is greater than the axial length of the outer ceramic ring (1), and both axial ends of the inner ceramic ring (4) protrude outside the outer ceramic ring (1), so that the axial ends of the inner ceramic ring (4) are in contact with the surface of the graphite boat; and A connecting ring (2) is arranged in the annular cavity and connects the inner ceramic ring (4) and the outer ceramic ring (1) together.
2. The inner and outer composite ceramic ring according to claim 1, characterized in that: The connecting ring (2) divides the annular cavity into two non-connected annular grooves (5).
3. The inner and outer composite ceramic ring according to claim 1, characterized in that: An uneven rough structure (3) is provided on the outer surface of the inner ceramic ring (4).
4. The inner and outer composite ceramic ring according to claim 3, characterized in that: The rough structure (3) comprises protrusions evenly distributed on the outer surface of the inner ceramic ring (4), and the shape of the protrusions is any one of a polygonal pyramid, a polygonal pyramid, and a spherical cap.
5. The inner and outer composite ceramic ring according to claim 4, characterized in that: The rough structure (3) comprises annular teeth formed on the outer surface of the inner ceramic ring (4) and surrounding along the axis of the inner ceramic ring (4).
6. The inner and outer composite ceramic ring according to claim 5, characterized in that: The shape of the annular teeth along the axial cross section of the inner ceramic ring (4) is triangular or trapezoidal.
7. The inner and outer composite ceramic ring according to claim 3, characterized in that: The rough structure (3) comprises spiral protrusions spirally formed on the outer surface of the inner ceramic ring (4).
8. The inner and outer composite ceramic ring according to claim 1, characterized in that: The inner diameter D1 of the outer ceramic ring (1) is greater than the outer diameter D2 of the inner ceramic ring (4), and the difference is 2-4 mm.
9. The inner and outer composite ceramic ring according to claim 1, characterized in that: The axial length L1 of the outer ceramic ring (1) is smaller than the axial length L2 of the inner ceramic ring (4), and the difference is 2-4 mm.
10. A graphite boat, characterized in that: An inner and outer composite ceramic ring as described in any one of claims 1 to 9 is provided.