A wafer support and chemical vapor deposition equipment

Abstract

This invention discloses a wafer support and a chemical vapor deposition (CVD) apparatus. The wafer support includes a rod and a head. The head has an upper surface and a lower surface. The upper surface is for contacting the back side of the wafer, and the lower surface is conical for mating with a conical hole on a heating plate. At least one airflow channel structure is provided on the lower surface. This airflow channel structure is configured to form an airflow channel between the lower surface and the conical hole of the heating plate, connecting the space above and below the heating plate. The airflow channel structure in this invention forms an airflow channel when the head mates with the conical hole, allowing continuous gas flow, eliminating dead zones, and reducing AlF powder adhesion on the rod. More specifically, this airflow channel maintains gas exchange within the PIN hole, preventing gap narrowing and restricted movement caused by powder accumulation, and extending the service life of the wafer support.

Description

Technical Field

[0001] This utility model relates to the field of chemical vapor deposition equipment technology, and in particular to a wafer support and chemical vapor deposition equipment. Background Technology

[0002] In chemical vapor deposition (CVD) equipment, wafer supports (commonly referred to as PINs) are used to support and lift wafers on a heated plate. Existing wafer supports are typically made of ceramic material and include a mushroom-shaped head and a PIN bar. A counterweight is mounted at the end of the PIN bar. The counterweight cooperates with the cavity base plate to lift the entire PIN bar to lift the wafer. When the wafer is not lifted, the mushroom head is located in the tapered hole of the heated plate, and the PIN bar is located in the PIN hole of the heated plate. A fitting clearance is designed between the PIN hole and the PIN bar to ensure that the PIN moves smoothly up and down in the PIN hole, while allowing a certain degree of thin film accumulation. However, during the clean process of CVD, gas containing AlF can diffuse into the PIN hole. When the PIN falls, the mushroom head blocks the PIN hole, creating a dead zone inside the PIN hole. This slows down or even stops the gas flow, causing AlF powder to adhere to and accumulate on the surface of the PIN rod, forming a thin film. Over time, the film thickness increases, resulting in a smaller fit clearance between the PIN rod and the PIN hole. This causes the PIN to get stuck in the PIN hole and become unable to move, eventually leading to PIN breakage and damage. This problem seriously affects the lifespan of the PIN and the stability of the process. Utility Model Content

[0003] The embodiments of this utility model provide a wafer support and a chemical vapor deposition apparatus, which aim to solve the technical problem that existing wafer supports are easily stuck in the PIN holes and cannot move.

[0004] To address the aforementioned problems, according to one aspect of this application, an embodiment of the present invention provides a wafer support member, the wafer support member comprising a rod and a head, the head having an upper surface and a lower surface, the upper surface being for contacting the back side of the wafer, the lower surface being a conical surface for engaging with a conical hole shape on a heating plate, the lower surface being provided with at least one airflow channel structure, the airflow channel structure being configured to form an airflow channel between the lower surface and the conical hole of the heating plate when the lower surface engages with the conical hole of the heating plate, for connecting the space above the heating plate and the space below the heating plate.

[0005] In some embodiments, the cross-sectional area of ​​the airflow channel structure gradually increases along the direction from the center of the lower surface to the edge.

[0006] In some embodiments, the airflow channel structure is a groove, and the number of grooves is at least two and they are evenly distributed on the circumference of the lower surface.

[0007] In some embodiments, the depth of the groove gradually decreases from the center of the lower surface to the edge, while the width gradually increases accordingly, forming a gradually expanding airflow channel.

[0008] In some embodiments, the airflow channel structure is a boss, the number of which is at least two and is evenly distributed on the circumference of the lower surface, the top surface of the boss is an arc-shaped guide surface, and the cross-sectional area of ​​the airflow channel formed between adjacent bosses gradually increases from the center of the lower surface to the edge.

[0009] In some embodiments, the rod is a cylinder with three slits, the three slits being evenly distributed on the circumference, and each slit forming a gas flow gap with the inner wall of the corresponding PIN hole.

[0010] In some embodiments, the rod and the head are integrally formed from a ceramic material, wherein the head is mushroom-shaped.

[0011] According to another aspect of this application, an embodiment of the present invention provides a chemical vapor deposition apparatus, the chemical vapor deposition apparatus including a heating plate and the aforementioned wafer support, the heating plate having a PIN hole, a rod located within the PIN hole, a counterweight mounted at the end of the rod, and the fitting clearance between the PIN hole and the rod being configured to allow the wafer support to move up and down within the PIN hole.

[0012] In some embodiments, the heating plate is provided with three wafer supports, which are evenly distributed on the heating plate, and the airflow channel structure of each wafer support is connected to the side of the PIN hole through a gap to form a continuous airflow path.

[0013] In some embodiments, the chemical vapor deposition apparatus further includes a cavity exhaust unit, the exhaust port of which is located below the heating plate, so that during the process or purging, the airflow channel structure through the PIN hole forms an airflow from bottom to top or from top to bottom.

[0014] Compared with the prior art, the wafer support of this utility model has at least the following beneficial effects: The wafer support component provided by this utility model includes a rod and a head. The head has an upper surface and a lower surface. The upper surface is used to contact the back side of the wafer, and the lower surface is a conical surface used to match the shape of the conical hole on the heating plate. At least one airflow channel structure is provided on the lower surface. The airflow channel structure is configured to form an airflow channel between the lower surface and the conical hole of the heating plate when the lower surface matches the conical hole of the heating plate, so as to connect the space above the heating plate and the space below the heating plate.

[0015] This invention solves the technical problems described in the background art by setting an airflow channel structure on the lower surface. The background art points out that when the PIN falls, the head will block the PIN hole, forming a dead zone, which causes the AlF gas flow to slow down and adhere to the surface of the rod, causing jamming and breakage. However, the airflow channel structure in this embodiment forms an airflow channel when the head and the tapered hole are engaged, allowing the gas to flow continuously, eliminating the dead zone, and thus reducing the adhesion of AlF powder on the rod. More specifically, this airflow channel maintains gas exchange in the PIN hole, prevents the problem of reduced gap and restricted movement caused by powder accumulation, and extends the service life of the wafer support.

[0016] The chemical vapor deposition equipment provided by this utility model is designed based on the above-mentioned wafer support. Its beneficial effects are the same as those of the above-mentioned wafer support, and will not be repeated here.

[0017] The above description is only an overview of the technical solution of this utility model. In order to better understand the technical means of this utility model and to implement it in accordance with the contents of the specification, the preferred embodiments of this utility model are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model, 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 of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0019] Figure 1 A schematic diagram of the structure of a wafer support component provided in an embodiment of this utility model; Figure 2 A partial structural diagram of a wafer support component provided in this embodiment of the present invention, wherein the airflow channel structure is a boss; Figure 3 A partial structural diagram of a wafer support component provided in this embodiment of the present invention, wherein the airflow channel structure is a groove; Figure 4 This is a partial structural diagram of a wafer support component and a heating plate in conjunction, provided by an embodiment of the present invention. Figure 5 A schematic diagram of a chemical vapor deposition apparatus provided in an embodiment of this utility model; Figure label explanation: 1. Rod; 2. Head; 21. Upper surface; 22. Lower surface; 23. Airflow channel structure; 3. Heating plate; 4. Counterweight. Detailed Implementation

[0020] To further illustrate the technical means and effects adopted by this utility model to achieve its intended purpose, the specific implementation methods, structures, features, and effects according to this utility model application are described in detail below with reference to the accompanying drawings and preferred embodiments. In the following description, different "an embodiment" or "an embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0021] In the description of this utility model, it should be clarified that the terms "first," "second," etc., in the specification, claims, and drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence; the terms "vertical," "lateral," "longitudinal," "front," "back," "left," "right," "up," "down," "horizontal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing this utility model, and do not mean that the device or element referred to must have a specific orientation or position, and therefore should not be construed as a limitation of this utility model.

[0022] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0023] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0024] Example 1 This embodiment provides a wafer support component, such as... Figures 1-5 As shown, the wafer support includes a rod 1 and a head 2. The head 2 has an upper surface 21 and a lower surface 22. The upper surface 21 is used to contact the back side of the wafer. The lower surface 22 is a conical surface used to fit the shape of a conical hole on the heating plate. The lower surface 22 is provided with at least one airflow channel structure 23. The airflow channel structure 23 is configured to form an airflow channel between the lower surface 22 and the conical hole of the heating plate when the lower surface 22 fits with the conical hole of the heating plate, for connecting the space above the heating plate and the space below the heating plate.

[0025] In the structure of the wafer support, the rod 1 is directly connected to the lower part of the head 2. The upper surface 21 of the head 2 is a flat plane for direct contact with the back side of the wafer, while the lower surface 22 of the head 2 is designed as an inclined conical surface facing the conical hole of the heating plate. The airflow channel structure 23 is set on the lower surface 22, evenly distributed or at least one. When the lower surface 22 of the head 2 is engaged with the conical hole of the heating plate, the airflow channel structure 23 will form a continuous airflow channel between the conical surface and the hole wall, thereby connecting the space above the heating plate and the space below the heating plate. More specifically, this positional relationship ensures that the gas can flow smoothly through the channel and avoid local blockage.

[0026] The function of the rod 1 is to support the entire wafer support and move it up and down within the PIN hole of the heating plate, thereby lifting and placing the wafer. The function of the head 2 is to provide a stable support surface through the upper surface 21 to contact the back of the wafer, while the tapered design of the lower surface 22 is designed to match the shape of the tapered hole of the heating plate, ensuring accurate positioning of the wafer support when not in operation. The function of the airflow channel structure 23 is to form an airflow channel when the lower surface 22 matches the tapered hole, promoting the flow of gas between the upper and lower spaces of the heating plate and preventing gas stagnation. These structures together reduce the accumulation of harmful powder on the surface of the rod 1, thereby maintaining the long-term reliability of the wafer support.

[0027] When the wafer support is working, the rod 1 moves up and down in the PIN hole under the action of the external weight. When lifting the wafer, the rod 1 pushes the head 2 upward, so that the upper surface 21 contacts the back of the wafer and lifts it up. When placing the wafer, the rod 1 moves downward, and the lower surface 22 of the head 2 mates with the conical hole of the heating plate. At this time, the airflow channel structure 23 forms an airflow channel between the two, allowing gas to flow from below the heating plate to above the heating plate or in the opposite direction, thereby maintaining continuous gas flow and preventing AlF gas from stagnating and condensing in the PIN hole. This ensures that no dead zone is formed in the PIN hole, making it difficult for powder to adhere to the surface of the rod 1, thus ensuring smooth operation of the wafer support.

[0028] This embodiment solves the technical problems described in the background art by setting an airflow channel structure 23 on the lower surface 22. The background art points out that when the PIN falls, the head 2 will block the PIN hole and form a dead zone, causing the AlF gas flow to slow down and adhere to the surface of the rod 1, resulting in jamming and breakage. However, the airflow channel structure 23 in this embodiment forms an airflow channel when the head 2 and the tapered hole are engaged, allowing the gas to flow continuously, eliminating the dead zone, thereby reducing the adhesion of AlF powder on the rod 1. More specifically, this airflow channel maintains gas exchange in the PIN hole, prevents the problem of reduced gap and restricted movement caused by powder accumulation, and extends the service life of the wafer support.

[0029] In a specific embodiment, the cross-sectional area of ​​the airflow channel structure 23 gradually increases along the direction from the center of the lower surface 22 to the edge.

[0030] As the airflow channel structure 23 extends outward from the center point on the lower surface 22 of the head 2, the cross-sectional size of the channel gradually increases. For example, by designing the shape of grooves or bosses, the channel becomes wider or deeper near the edge, thereby forming a diffused airflow path. More specifically, this design ensures that the gas flows more smoothly as it moves from below the heating plate to above the heating plate, reducing local resistance and turbulence. Furthermore, this change in cross-sectional area optimizes the distribution and velocity of the gas within the channel, preventing the gas from stagnating in specific areas, thus effectively avoiding the formation of dead zones, reducing the chance of AlF powder adhering to the surface of the rod 1, extending the lifespan of the wafer support, and improving process stability.

[0031] In a specific embodiment, such as Figure 3 The airflow channel structure 23 shown is a groove, and the number of the grooves is at least two and they are evenly distributed on the circumference of the lower surface 22.

[0032] The airflow channel structure 23 is specifically in the form of grooves, and there are at least two of these grooves, which are evenly distributed on the circumference of the lower surface 22. This means that multiple recessed grooves are provided on the lower surface 22 of the conical surface of the head 2, which surround the circumference at equal intervals, forming a series of symmetrical airflow paths. More specifically, this evenly distributed groove design ensures that when the lower surface 22 of the head 2 mates with the conical hole of the heating plate, the gas can flow evenly from below the heating plate to above the heating plate in multiple directions, avoiding gas accumulation or stagnation in a certain area, thereby effectively preventing the formation of dead zones. Furthermore, the multiple grooves provide redundant flow channels. Even if individual channels are partially blocked due to powder accumulation, other channels can still maintain gas flow. This significantly reduces the probability of AlF gas retention and condensation in the PIN hole, reduces powder adhesion on the surface of the rod 1, thereby avoiding PIN jamming and breakage problems, and improving the reliability and durability of the wafer support.

[0033] In a specific embodiment, the depth of the groove gradually decreases from the center of the lower surface 22 to the edge, while the width gradually increases accordingly, forming a gradually expanding airflow channel.

[0034] These vertical grooves are deepest and narrowest at their middle position in the vertical direction, and then gradually become shallower and wider as they extend towards the upper end of the groove (i.e., towards the upper surface 21 of the head 2) and the lower end of the groove (i.e., towards the rod 1), thus forming a smooth "spindle-shaped" or "drum-shaped" channel that expands from the middle to both the upper and lower ends on the vertical cross-section of a single groove. More specifically, this unique three-dimensional structural design makes the deepest area in the middle of the groove a gas collection and transfer node when the mushroom head falls and engages with the conical hole of the heating plate, while the outlet that widens to both the upper and lower ends greatly optimizes the efficiency of gas inflow and outflow. Furthermore, this gradually expanding shape can guide the gas to accelerate and diffuse smoothly as it flows through the groove, effectively breaking up any eddies that may form and completely destroying the conditions for the formation of the original closed dead zone. This ensures that the gas containing AlF cannot remain in the PIN hole, thereby cutting off the root cause of powder adhesion on the surface of the rod 1. Ultimately, this solves the long-standing technical problem of PIN breakage due to jamming, and significantly improves the working life and process reliability of the wafer support.

[0035] In a specific embodiment, such as Figure 2 As shown, the airflow channel structure 23 is a boss, and the number of bosses is at least two and they are evenly distributed on the circumference of the lower surface. The top surface of the boss is an arc-shaped guide surface, and the cross-sectional area of ​​the airflow channel formed between adjacent bosses gradually increases from the center of the lower surface 22 to the edge.

[0036] When head 2 descends and engages with the conical hole of the heating plate, the boss itself provides support to ensure a stable gap between head 2 and the hole wall. The gaps between the bosses create multiple paths that allow gas flow. These paths are relatively narrow near the center and widen towards the periphery. Simultaneously, the arc-shaped surface at the top of the boss guides the gas flow, reducing eddies or resistance caused by impact with the surface. Furthermore, this gradually expanding channel design, combined with the arc-shaped guide surface, allows gas entering from below the heating plate to be smoothly and efficiently guided and diffused into the vast space above the heating plate. This completely breaks the previously closed dead zone within the PIN hole, ensuring that process gases containing AlF cannot stagnate or condense on the surface of the rod 1. This fundamentally eliminates the PIN jamming and breakage problems caused by continuous powder accumulation, significantly improving the reliability and durability of the wafer support during long-term cyclic use.

[0037] In a specific embodiment, the rod 1 is a cylinder with three slits, the three slits are evenly distributed on the circumference, and each slit forms a gas flow gap with the inner wall of the corresponding PIN hole.

[0038] The rod 1 is specifically constructed as a cylindrical structure with three tangled edges, which are evenly arranged along the circumference of the rod 1. This means that, from a cross-sectional perspective, it is no longer a complete circle, but rather composed of three alternating arc surfaces and three flat surfaces. When this specially shaped rod 1 is inserted into the corresponding PIN hole on the heating plate, since the PIN hole is typically a standard circular hole, each tangled surface on the rod 1 forms a gap of a specific size extending axially with the circular inner wall of the PIN hole. This gap constitutes an additional gas flow gap. More specifically, this design pre-creates multiple stable and evenly distributed gas paths between the rod 1 and the inner wall of the PIN hole, which would otherwise fit tightly. These gas flow gaps work in conjunction with the gas flow channel structure 23 provided on the lower surface 22 of the head 2 to form a three-dimensional, redundant gas flow network. Furthermore, even in extreme cases where the channel on the lower surface 22 of the head 2 becomes partially blocked due to long-term use, the tangential gaps on the rod 1 still ensure effective gas exchange and flow between the upper and lower spaces of the heating plate, thereby significantly improving the reliability of the entire system. This continuous gas flow effectively disrupts the formation conditions of dead zones within the PIN hole, preventing AlF-containing gas from stagnating and condensing into solid powder on the surface of the rod 1. This fundamentally solves the risk of rod 1 jamming with the PIN hole and the resulting breakage caused by continuous powder accumulation. In addition, the uniform distribution of the three tangential edges ensures that the rod 1 is subjected to uniform force within the PIN hole, avoiding uneven wear or jamming that may be caused by unilateral friction or uneven powder accumulation. This further extends the service life of the wafer support and maintains the stability of the process.

[0039] In a specific embodiment, the rod 1 and the head 2 are integrally formed from ceramic material, wherein the head 2 is mushroom-shaped.

[0040] The rod 1 and head 2 are not manufactured separately and then assembled, but are integrally manufactured from ceramic material in a single processing step, forming a single, continuous, seamless structure. The head 2 is mushroom-shaped, meaning its size is typically larger than the rod 1 below it, forming a canopy-like protrusion. Its upper surface 21 is flat to support the wafer, while its lower surface 22 is machined into a conical surface to accommodate the conical holes on the heating plate. Integrating these two parts from ceramic material offers several significant advantages. First, it completely eliminates any potential seams, interfaces, or micro-gaps between the rod 1 and head 2, areas that are often weak points in mechanical strength in split structures and prone to fracture due to stress concentration. The integral structure provides the entire wafer support with higher overall structural integrity and mechanical strength, enabling it to better withstand the cyclic stresses and potential lateral forces generated during repeated wafer lifting and placing. Second, ceramic material itself possesses excellent high-temperature resistance, corrosion resistance, and low-pollution properties, making it ideal for CVD process environments, while the integral molding technology further ensures the dimensional stability and reliability of the component under harsh thermal cycling. Furthermore, this seamless construction not only improves mechanical performance but also simplifies the manufacturing process. The absence of assembly gaps also reduces potential hiding places and accumulation of process byproduct powder. Combined with its mushroom-shaped design, it can stably and precisely engage with the heating plate, ensuring support while working in conjunction with the chamfered edge design of the rod 1 or the airflow channel structure 23 on the head 2 to ensure unobstructed gas flow. This effectively alleviates powder adhesion and jamming issues, ultimately improving the durability and process stability of the wafer support during long-term use.

[0041] During the complete operation of the wafer support, when the wafer needs to be placed on the heating plate, the rod 1 moves downward under the action of the weight, so that the lower surface 22 of the head 2 fits tightly with the conical hole of the heating plate. At this time, the upper surface 21 of the head 2 is lower than the heating plate surface, and the wafer is stably supported on the heating plate. More specifically, in this state, due to its cylindrical structure with three tangs, the rod 1 forms a uniform gas flow gap between each tang and the inner wall of the PIN hole. At the same time, the airflow channel structure 23 on the lower surface 22 of the head 2, whether in the form of a groove or a boss, will create multiple airflow paths between the conical surface and the hole wall. The cross-sectional area of ​​these paths gradually increases from the center to the edge according to the design. For example, the depth of the groove decreases from the center to the edge while the width increases, or the channel between the bosses is gradually expanding. The arc-shaped guide surface on the top surface of the boss can smoothly guide the gas flow. Furthermore, during the clean cycle of the CVD process, gas containing AlF enters the PIN hole from below the heating plate. Due to the existence of these pre-designed airflow channels and gaps, the gas no longer stagnates but flows smoothly to the space above the heating plate through the chamfer gap of the rod 1 and the airflow channel structure 23 of the head 2, forming continuous gas exchange and thus avoiding the formation of dead zones. When it is necessary to lift the wafer, the counterweight and the cavity base plate work together to push the rod 1 upward. The rod 1 drives the head 2 to rise, so that the upper surface 21 contacts the back of the wafer and lifts it off the heating plate. Since the rod 1 and the head 2 are integrally formed from ceramic material, they have high strength and stability and can withstand repeated stress during the entire up and down movement without easily breaking. At the same time, the airflow channel continuously ensures gas flow and prevents AlF powder from adhering and accumulating on the surface of the rod 1, ultimately achieving smooth operation of the wafer support and extending its long service life.

[0042] Example 2 This embodiment provides a chemical vapor deposition apparatus, such as... Figure 5 As shown, the chemical vapor deposition apparatus includes a heating plate 3 and a wafer support as described in Example 1. The heating plate 3 is provided with a PIN hole, the rod 1 is located in the PIN hole, a weight 4 is installed at the end of the rod 1, and the fitting clearance between the PIN hole and the rod 1 is configured to allow the wafer support to move up and down in the PIN hole.

[0043] The heating plate 3 has PIN holes, and the rod 1 of the wafer support is located inside the PIN holes, with a counterweight 4 installed at the end of the rod 1. The fit clearance between the PIN holes and the rod 1 is a carefully designed dimension. This clearance must ensure that the rod 1 can move smoothly up and down within the PIN holes without obstruction to lift and lower the wafer, while also not being too large to affect the wafer's positioning accuracy. By integrating the improved wafer support into the chemical vapor deposition equipment and combining it with the heating plate 3, its PIN holes, and the counterweight 4 into a collaborative system, a series of positive effects have been achieved. This configuration allows the gap formed between the tangential structure of the rod 1 and the inner wall of the PIN holes, and the airflow channel structure 23 on the lower surface 22 of the head 2, during normal operation, to establish an effective gas flow path between the upper and lower spaces of the heating plate 3. This ensures that during the process, especially in the cleaning stage, gases containing AlF cannot stagnate within the PIN holes, forming dead zones, thus fundamentally preventing the adhesion and accumulation of harmful powders on the surface of the rod 1. The ultimate effect is to significantly improve the process stability and production reliability of the entire chemical vapor deposition equipment, greatly reduce the frequency of equipment downtime and maintenance caused by wafer support jamming or breakage, extend the service life of key consumables, and ensure the continuous and efficient operation of the production process.

[0044] In a specific embodiment, the heating plate 3 is provided with three wafer support members, which are evenly distributed on the heating plate 3. The airflow channel structure 23 of each wafer support member is connected to the side of the PIN hole through a gap to form a continuous airflow path.

[0045] Three wafer supports are arranged symmetrically and uniformly on the heating plate 3, providing stable and balanced support for the wafers. More importantly, the airflow channel structure 23 on the lower surface 22 of the head 2 of each wafer support, whether in the form of a groove or a boss, is interconnected with the side fitting gap between the rod 1 and the inner wall of the PIN hole, forming a complete and continuous unobstructed gas flow path from the space below the heating plate, through the inside of the PIN hole, through the airflow channel structure 23, and finally to the space above the heating plate. This multi-point uniform distribution layout, combined with the continuous and unobstructed airflow design, ensures that during equipment operation, especially in the clean process, the gas entering from below the heating plate 3 can be evenly distributed into these three independent but structurally identical airflow channels. Each of these airflow channels efficiently guides gas flow, preventing stagnation in any local area. This design greatly enhances the efficiency and thoroughness of gas exchange between the upper and lower spaces of the heating plate. The three supports form a triple guarantee, ensuring that even if a particular channel changes slightly due to long-term use, the overall airflow remains unobstructed. The direct effect is to completely eliminate the dead zone formed by gas stagnation in the PIN hole, so that gas molecules with AlF components cannot stay on the surface of the rod 1 and condense into solid powder, thereby fundamentally curbing the risk of PIN jamming and breakage caused by powder accumulation.

[0046] In a specific embodiment, the chemical vapor deposition apparatus further includes a cavity exhaust unit, the exhaust port of which is located below the heating plate 3, so that during the process or purging, the airflow channel structure 23 of the PIN hole forms an airflow from bottom to top or from top to bottom.

[0047] This embodiment also integrates a cavity exhaust unit, with its exhaust port located below the heating plate 3. This key layout allows the equipment to flexibly utilize the airflow channel structure 23 on the lower surface 22 of the wafer support head 2 to guide a stable and directionally controllable airflow, whether during normal process operation or during dedicated purging. More specifically, when the exhaust unit operates, it creates a localized low-pressure area below the heating plate 3, and this pressure difference naturally drives gas flow. Gas can flow from the space above the heating plate 3 through the airflow channel structure 23 of the head 2, through the mating gap between the rod 1 and the inner wall of the PIN hole, and finally be drawn to the exhaust port below the heating plate 3, thus forming a top-down airflow path. Conversely, in another operating mode, if it works in conjunction with a unit that supplies purging gas to the area below the heating plate 3, it can enhance the bottom-up airflow. Furthermore, this bidirectional airflow capability greatly enhances the dynamic control of the internal environment of the PIN hole. Regardless of the flow direction, the gas continuously flowing through the gas flow channel structure 23 effectively transforms the PIN hole from a static dead zone into a dynamic channel continuously swept by the gas. This ensures that any AlF gas molecules that may condense or existing tiny powder particles cannot remain and accumulate on the surface of the rod 1, thereby fundamentally eliminating the risk of wafer support jamming and breakage due to powder accumulation, and significantly improving the reliability and maintenance cycle of the equipment.

[0048] The chemical vapor deposition equipment provided in this embodiment combines a wafer support with a gas flow channel structure with a heating plate, its PIN holes, and a counterweight, ensuring the smoothness and reliability of the wafer support's up-and-down movement within the PIN holes, thus laying the foundation for the entire process.

[0049] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A wafer support, characterized in that, The wafer support includes a rod and a head. The head has an upper surface and a lower surface. The upper surface is for contacting the back side of the wafer. The lower surface is a conical surface for fitting with the conical hole shape on the heating plate. The lower surface is provided with at least one airflow channel structure. The airflow channel structure is configured to form an airflow channel between the lower surface and the conical hole of the heating plate when the lower surface fits with the conical hole of the heating plate, for connecting the space above the heating plate and the space below the heating plate.

2. The wafer support according to claim 1, characterized in that, The cross-sectional area of ​​the airflow channel structure gradually increases along the direction from the center of the lower surface to the edge.

3. The wafer support according to claim 1, characterized in that, The airflow channel structure is a groove, and the number of grooves is at least two and they are evenly distributed on the circumference of the lower surface.

4. The wafer support according to claim 3, characterized in that, The depth of the groove gradually decreases from the center of the lower surface to the edge, while the width gradually increases accordingly, forming a gradually expanding airflow channel.

5. The wafer support according to claim 1, characterized in that, The airflow channel structure is a boss, and there are at least two bosses that are evenly distributed on the circumference of the lower surface. The top surface of the boss is an arc-shaped guide surface, and the cross-sectional area of ​​the airflow channel formed between adjacent bosses gradually increases from the center of the lower surface to the edge.

6. The wafer support according to claim 1, characterized in that, The rod is a cylinder with three slits, which are evenly distributed on the circumference, and each slit forms a gas flow gap with the inner wall of the corresponding PIN hole.

7. The wafer support according to claim 1, characterized in that, The rod and the head are integrally formed from ceramic material, wherein the head is mushroom-shaped.

8. A chemical vapor deposition apparatus, characterized in that, The chemical vapor deposition apparatus includes a heating plate and a wafer support as described in any one of claims 1-7. The heating plate has a PIN hole, the rod is located in the PIN hole, a weight is installed at the end of the rod, and the fit clearance between the PIN hole and the rod is configured to allow the wafer support to move up and down in the PIN hole.

9. The chemical vapor deposition apparatus according to claim 8, characterized in that, The heating plate is equipped with three wafer support members, which are evenly distributed on the heating plate. The airflow channel structure of each wafer support member is connected to the side of the PIN hole through a gap to form a continuous airflow path.

10. The chemical vapor deposition apparatus according to claim 8, characterized in that, The chemical vapor deposition apparatus also includes a cavity exhaust unit, the exhaust port of which is located below the heating plate, so that during the process or purging, the airflow channel structure through the PIN hole forms an airflow from bottom to top or from top to bottom.

Images