Insulating ceramic sleeve and graphite boat
By using the L-shaped isolation cavity design and rough structure of the insulated ceramic sleeve in the graphite boat, the problem of degradation of the insulation performance of the ceramic ring is solved, the insulation performance is extended and the product quality is improved, and the rework rate and production cost are reduced.
Patent Information
- Application Number
- CN202422654451.9
- 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 insulation performance of the ceramic ring is degraded due to the deposit of conductive film during use, 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 insulating ceramic sleeve design is adopted, including the first insulating member and the second insulating member, forming an L-shaped isolation cavity. The outer surface of the inner insulating sleeve is equipped with a rough structure with uneven concave and convexity, and a narrow slit and bent runner design to delay the deposition of the conductive film on the surface of the inner insulating sleeve and ensure the insulation effect.
The insulation usage cycle of the inner insulating sleeve is extended, preventing the conduction between the positive and negative plates of the graphite boat, improving product quality and yield, reducing the rework rate, reducing the frequency of replacing the ceramic sleeve, shortening the production cycle and reducing costs.
Smart Images
Figure CN223280936U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of graphite boats, and particularly relates to an insulating ceramic sleeve and a graphite boat. 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 embodiments of the present invention provide an insulating ceramic sleeve and a graphite boat, which are intended to delay the deposition time of a conductive film on a 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 otherwise cause a decline in product quality, a decrease in yield, and an increase in the rework rate.
[0005] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: to provide an insulating ceramic sleeve, comprising: a first insulating part and a second insulating part, the first insulating part having an outer insulating sleeve and a first insulating end cover integrally formed at one end of the outer insulating sleeve; the second insulating part having an inner insulating sleeve and a second insulating end cover integrally formed at one end of the inner insulating sleeve; the outer diameter of the inner insulating sleeve is smaller than the inner diameter of the outer insulating sleeve, the inner insulating sleeve is coaxially sleeved in the outer insulating sleeve, and the axial end of the inner insulating sleeve is axially fixed on the inner surface of the first insulating end cover; the second insulating end cover is exposed to the outside of the outer insulating sleeve, and an axial gap is provided between the second insulating end cover and the outer insulating sleeve, and an annular gap is formed between the inner insulating sleeve and the outer insulating sleeve; the axial gap is connected to the annular gap so that an L-shaped isolation cavity is formed between the second insulating part and the first insulating part.
[0006] In combination with the first aspect, in one achievable manner, an uneven rough structure is provided on the outer surface of the inner insulating sleeve.
[0007] In combination with the first aspect, in one achievable manner, the rough structure includes protrusions uniformly distributed on the outer surface of the inner insulating sleeve, and the shape of the protrusions is any one of a polygonal pyramid, a polygonal pyramid, and a spherical cap.
[0008] In combination with the first aspect, in one achievable manner, the rough structure includes annular teeth formed on the outer surface of the inner insulating sleeve and surrounding along the axis of the inner insulating sleeve.
[0009] In combination with the first aspect, in one achievable manner, the shape of the annular teeth along the axial cross-section of the inner insulating sleeve is a triangle or a trapezoid.
[0010] 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 insulating sleeve.
[0011] In combination with the first aspect, in one achievable manner, the inner diameter D1 of the outer insulating sleeve is larger than the outer diameter D2 of the inner insulating sleeve, and the difference is 2-4 mm.
[0012] In combination with the first aspect, in one achievable manner, the axial gap L is 2-4 mm.
[0013] In combination with the first aspect, in one achievable manner, the outer diameter of the first insulating end cover is the same as the outer diameter of the outer insulating sleeve; and the outer diameter of the second insulating end cover is greater than or equal to the outer diameter of the outer insulating sleeve.
[0014] In a second aspect, an embodiment of the present invention further provides a graphite boat, comprising the insulating ceramic sleeve.
[0015] Compared with the prior art, the insulating ceramic sleeve and graphite boat provided by the present invention have the following beneficial effects: the second insulating member is directly connected to the first insulating member as a whole, and the first insulating member and the second insulating member are coaxially mounted to form an L-shaped isolation cavity. 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 outer surface of the first insulating member. Since the overall size of the ceramic sleeve is relatively small, generally at the millimeter level, a narrow and narrow gap and a bent L-shaped isolation cavity are formed between the first insulating member and the second insulating member. The reaction gas will be blocked in the narrow and bent gap, which is not conducive to the deposition of a conductive film on the outer surface of the inner insulating sleeve, and is even more not conducive to the formation of a uniform conductive film on the outer surface of the inner insulating sleeve. Therefore, the protection of the inner insulating sleeve by the outer insulating sleeve and the L-shaped isolation cavity formed between the two can extend the life of the insulating sleeve. The period of depositing a conductive film on the outer surface of the inner insulating sleeve to form a conductor is delayed; and since the first insulating end cover and the second insulating end cover are in contact with the graphite boat at both axial ends, an axial gap is formed between the outer insulating sleeve and the second insulating end cover, so the inner insulating sleeve can insulate between adjacent graphite boats, and since it is the inner insulating sleeve that performs the insulating function, the effective insulating service life of the inner insulating sleeve as an insulator can be extended by delaying the time of depositing a conductive film on the outer surface of the inner insulating sleeve to form a conductor, 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 period of forming the conductor by the inner insulating sleeve is increased, the service life of the entire insulating ceramic sleeve is also extended, thereby reducing the time and cost of replacing the entire ceramic sleeve, and also helping to shorten the production cycle and reduce production costs. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 A schematic diagram of the cross-sectional structure of the insulating ceramic sleeve provided in an embodiment of the present utility model along the axial direction;
[0017] Figure 2 for Figure 1 The left side structural diagram of the provided insulating ceramic sleeve;
[0018] Description of reference numerals:
[0019] 1. First insulating member; 11. Outer insulating sleeve; 12. First insulating end cap; 2. Second insulating member; 21. Inner insulating sleeve; 22. Second insulating end cap; 3. Rough structure; 4. Axial gap; 5. Annular gap; 6. Through hole. 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 insulating ceramic sleeve provided by the present invention is now described. The insulating ceramic sleeve includes a first insulating member 1 and a second insulating member 2. The first insulating member 1 has an outer insulating sleeve 11 and a first insulating end cap 12 integrally formed at one end of the outer insulating sleeve 11; the second insulating member 2 has an inner insulating sleeve 21 and a second insulating end cap 22 integrally formed at one end of the inner insulating sleeve 21; the outer diameter of the inner insulating sleeve 21 is smaller than the inner diameter of the outer insulating sleeve 11, the inner insulating sleeve 21 is coaxially sleeved in the outer insulating sleeve 11, and the axial end of the inner insulating sleeve 21 is axially fixed to the inner surface of the first insulating end cap 12; the second insulating end cap 22 is exposed to the outside of the outer insulating sleeve 11, and an axial gap 4 is formed between the second insulating end cap 22 and the outer insulating sleeve 11, and an annular gap 5 is formed between the inner insulating sleeve 21 and the outer insulating sleeve 11; the axial gap 4 is connected to the annular gap 5 so that an L-shaped isolation cavity is formed between the second insulating member 2 and the first insulating member 1.
[0022] The insulating ceramic sleeve provided by the present invention has the following beneficial effects compared with the prior art: the second insulating member 2 is directly connected to the first insulating member 1 as a whole, and the first insulating member 1 and the second insulating member 2 are coaxially mounted to form an L-shaped isolation cavity therebetween. 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 outer surface of the first insulating member 1. Since the overall size of the ceramic sleeve is relatively small, generally at the millimeter level, a narrow and narrow gap and a bent L-shaped isolation cavity are formed between the first insulating member 1 and the second insulating member 2. The reaction gas is obstructed in the narrow and bent gap, which is not conducive to the deposition of a conductive film on the outer surface of the inner insulating sleeve 21, and is even more not conducive to the formation of a uniform conductive film on the outer surface of the inner insulating sleeve 21. Therefore, the protection of the inner insulating sleeve 21 by the outer insulating sleeve 11 and the L-shaped isolation cavity formed between the two can delay the formation of a conductive film on the inner insulating sleeve 21. The outer surface of the sleeve 21 is deposited with a conductive film to form a conductor; and since the first insulating end cover 12 and the second insulating end cover 22 are in contact with the graphite boat at both axial ends, an axial gap 4 is formed between the outer insulating sleeve 11 and the second insulating end cover 22, so the inner insulating sleeve 21 can insulate between adjacent graphite boats, and since it is the inner insulating sleeve 21 that plays the role of insulation, the effective insulation service life of the inner insulating sleeve 21 as an insulator can be extended by delaying the time for depositing a conductive film on the outer surface of the inner insulating sleeve 21 to form a conductor, 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 period of the inner insulating sleeve 21 forming the conductor is increased, the service life of the entire insulating ceramic sleeve is also extended, thereby reducing the time and cost of replacing the entire ceramic sleeve, which is also conducive to shortening the production cycle and reducing production costs.
[0023] The present application has a simple structure, and the two insulating parts are directly connected or integrally formed, with high structural strength, which can avoid the problem of breakage and damage during use, thereby also improving the overall service life.
[0024] The inner hole of the inner insulating sleeve 21 , the inner hole of the first insulating end cover 12 , and the inner hole of the second insulating end cover 22 have the same diameter, forming a through hole 6 .
[0025] The L-shaped isolation cavity is specifically formed along the axial cross section of the outer insulating sleeve 11 .
[0026] Regarding the difficulty in depositing a conductive film on the outer surface of the inner insulating sleeve 21 to form a conductor, it can be understood that due to the existence of the L-shaped isolation cavity between the first insulating part 1 and the second insulating part 2, the flow channel formed by the L-shaped isolation cavity is not only bent, but also narrow in radial width and has a certain depth in axial direction, which is not conducive to the diffusion of the reaction gas into the annular gap 5. Therefore, the thickness of the conductive film deposited on the outer part of the inner insulating sleeve 21 will be faster than that at the depth of the annular gap 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 inner insulating sleeve 21, the inner insulating sleeve 21 still has an insulating effect. If the thickness of the conductive film on the surface of the inner insulating sleeve 21 is uneven, the insulating performance of the inner insulating sleeve 21 is still effective, thereby extending the time for forming the conductive layer on the outer surface of the inner insulating sleeve 21, and thus the overall insulation service life of the insulating ceramic sleeve can be extended.
[0027] In the present application, the first insulating member 1 and the second insulating member 2 are made of ceramic materials.
[0028] In some embodiments, see Figure 1 As shown, the outer surface of the inner insulating sleeve 21 is provided with an uneven roughness 3. The uneven roughness 3 formed on the outer surface of the inner insulating sleeve 21 can provide a certain barrier to the reaction gas, making it difficult for a conductive film to form on the rough surface, and even more difficult to form a uniform conductive film on the rough surface. This prolongs the time it takes for the conductive layer to form on the outer surface of the inner insulating sleeve 21, thereby providing reliable insulation between the insulating end caps at both ends of the inner insulating sleeve 21, thereby extending the insulation life of the entire ceramic sleeve and preventing conductive short circuits between adjacent graphite boats, which can lead to failures and affect product quality and yield. If insulation failure of the inner insulating sleeve 21 causes conductive contact between two adjacent graphite boats, this can result in uneven amorphous silicon film deposition on the silicon wafer, resulting in substandard product quality after testing, necessitating rework and re-coating. This increases the rework rate of silicon wafer coating and correspondingly increases production costs and production cycle time.
[0029] In some embodiments, see Figure 1 As shown, the rough structure 3 includes protrusions evenly distributed on the outer surface of the inner insulating sleeve 21. The protrusions are in the shape of a polygonal pyramid, a polygonal pyramid, or a spherical cap. The protrusions formed on the outer surface of the inner insulating sleeve 21 have a blocking effect on the reaction gas. Even if the reaction gas enters the annular gap 5, the protrusions will prevent the reaction gas from being evenly deposited on the outer surface of the inner insulating sleeve 21. This prolongs the time it takes to form a conductive layer on the outer surface of the inner insulating sleeve 21 and improves the overall insulation life of the ceramic sleeve. Among them, this application only lists some of the protrusion shapes, and the protrusions can also have other irregular shapes.
[0030] In some embodiments, see Figure 1 As shown, the roughness structure 3 includes annular teeth formed on the outer surface of the inner insulating sleeve 21 and circumferentially extending along the axis of the inner insulating sleeve 21. Based on the above analysis of the outer surface roughness structure 3 of the inner insulating sleeve 21 delaying the formation of the conductive layer, the annular teeth can also delay the period of formation of the conductive layer on the outer surface of the inner insulating sleeve 21.
[0031] In some embodiments, the shape of the annular teeth along the axial cross-section of the inner insulating sleeve 21 is triangular or trapezoidal, which can also extend the period of forming the conductive layer on the outer surface of the inner insulating sleeve 21 .
[0032] In some embodiments, the roughness structure 3 includes a spiral protrusion formed on the outer surface of the inner insulating sleeve 21, which can also extend the period of forming the conductive layer on the outer surface of the inner insulating sleeve 21. Specifically, the spiral protrusion can be a thread structure.
[0033] In some embodiments, see Figure 1 As shown, the inner diameter D1 of the outer insulating sleeve 11 is larger than the outer diameter D2 of the inner insulating sleeve 21, with a difference of 2-4 mm. This indicates that the overall dimensions of the ceramic sleeve are relatively small, and the resulting annular gap 5 is a narrow gap, which is not conducive to 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 insulating sleeve 21. The difference between the inner diameters of the outer insulating sleeve 11 and the inner insulating sleeve 21 is typically 3 mm.
[0034] In some embodiments, see Figure 1 As shown, the width L of the axial gap 4 is 1-4 mm. Typically, the axial gap 4 is 1.5 mm, 2 mm, or 3 mm. When the second insulating end cap 22 of the second insulating member 2 and the first insulating end cap 12 of the first insulating member 1 abut the graphite boat, the 1.5 mm gap between the outer insulating sleeve 11 and the second insulating end cap 22 prevents electrical conduction between the graphite boat and thus does not affect the coating quality of the silicon wafer.
[0035] Since the outer insulating sleeve 11 does not play a role in conduction and insulation, it only protects the inner insulating sleeve 21, forms the annular gap 5 and delays the time of depositing the conductive film on the outer surface of the inner insulating sleeve 21. Therefore, the outer surface of the outer insulating sleeve 11 can be a smooth surface.
[0036] In some embodiments, see Figure 1 As shown, the outer diameter of the first insulating end cap 12 is the same as the outer diameter of the outer insulating sleeve 11; the outer diameter of the second insulating end cap 22 is greater than or equal to the outer diameter of the outer insulating sleeve 11. Preferably, the outer diameter of the second insulating end cap 22 is the same as the outer diameter of the first insulating end cap 12, which not only saves material but also creates a neat appearance.
[0037] 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.
[0038] Based on the same inventive concept, an embodiment of the present application further provides a graphite boat provided with the inner and outer composite ceramic rings.
[0039] The two insulating parts of the present application are combined together to form a connected and L-shaped narrow cavity inside. Therefore, during thin film deposition, even if a thin film of conductive material is deposited on the outer surface of the first insulating part 1 and the outer surface of the second insulating end cover 22 in the second insulating part 2, it is difficult to form a thin film deposition on the outer surface of the inner insulating sleeve 21 in the annular gap 5, especially it is difficult to form deposition on the rough outer surface, thereby ensuring the insulation effect of the two insulating end covers, improving product quality and product yield, reducing the rework rate of coated products, and at the same time reducing the time and cost of replacing ceramic rings, which is also conducive to shortening the production cycle and reducing production costs.
[0040] 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 insulating ceramic sleeve, characterized in that: include: A first insulating member (1) comprises an outer insulating sleeve (11) and a first insulating end cap (12) integrally formed at one end of the outer insulating sleeve (11); as well as The second insulating member (2) comprises an inner insulating sleeve (21) and a second insulating end cover (22) integrally formed at one end of the inner insulating sleeve (21); the outer diameter of the inner insulating sleeve (21) is smaller than the inner diameter of the outer insulating sleeve (11); the inner insulating sleeve (21) is coaxially sleeved in the outer insulating sleeve (11), and the axial end of the inner insulating sleeve (21) is axially fixed to the inner surface of the first insulating end cover (12); the second insulating end cover (22) is exposed outside the outer insulating sleeve (11), and an axial gap (4) is provided between the second insulating end cover (22) and the outer insulating sleeve (11); an annular gap (5) is formed between the inner insulating sleeve (21) and the outer insulating sleeve (11); the axial gap (4) is connected to the annular gap (5) so that an L-shaped isolation cavity is formed between the second insulating member (2) and the first insulating member (1).
2. The insulating ceramic sleeve according to claim 1, wherein: An uneven rough structure (3) is provided on the outer surface of the inner insulating sleeve (21).
3. The insulating ceramic sleeve according to claim 2, wherein: The rough structure (3) comprises protrusions evenly distributed on the outer surface of the inner insulating sleeve (21), and the shape of the protrusions is any one of a polygonal pyramid, a polygonal pyramid, and a spherical cap.
4. The insulating ceramic sleeve according to claim 2, wherein: The rough structure (3) comprises annular teeth formed on the outer surface of the inner insulating sleeve (21) and surrounding along the axis of the inner insulating sleeve (21).
5. The insulating ceramic sleeve according to claim 4, characterized in that: The shape of the annular teeth along the axial cross section of the inner insulating sleeve (21) is a triangle or a trapezoid.
6. The insulating ceramic sleeve according to claim 2, wherein: The rough structure (3) comprises spiral protrusions spirally formed on the outer surface of the inner insulating sleeve (21).
7. The insulating ceramic sleeve according to claim 1, wherein: The inner diameter D1 of the outer insulating sleeve (11) is greater than the outer diameter D2 of the inner insulating sleeve (21), and the difference is 2-4 mm.
8. The insulating ceramic sleeve according to claim 1, wherein: The axial gap (4) L is 2-4 mm.
9. The insulating ceramic sleeve according to claim 1, wherein: The outer diameter of the first insulating end cover (12) is the same as the outer diameter of the outer insulating sleeve (11); and the outer diameter of the second insulating end cover (22) is greater than or equal to the outer diameter of the outer insulating sleeve (11).
10. A graphite boat, characterized in that: The insulating ceramic sleeve comprises the insulating ceramic sleeve according to any one of claims 1 to 9.