A PECVD plate heater

Abstract

The utility model relates to the field of thin film deposition, especially a PECVD plate type heater, including bearing plate, first heating component and second heating component. Bearing plate has the first side surface and the second side surface of relative settings, and the second side surface of bearing plate is provided with the thermal resistance flange for connecting external circuit. First heating component includes the first heating wire of embedding connection in the first side surface of bearing plate, and first heating wire is armored heating cable and all with thermal resistance flan electric connection. Second heating component includes the second heating wire of embedding connection in the second side surface of bearing plate, and second heating wire all is armored heating cable with thermal resistance flan electric connection, and second heating component and first heating component independent operation each other. Through double -sided heating, the deformation of bearing plate and the generation of yellow powder are restrained, help to prolong the service life, improve the deposition thin film quality.

Description

Technical Field

[0001] This utility model relates to the field of thin film deposition, and in particular to a PECVD plate heater. Background Technology

[0002] Plasma-enhanced chemical vapor deposition (PECVD) is a low-temperature deposition technique with advantages such as temperature matching for thermosensitive materials, high uniformity of deposited films, high deposition rate, and applicability to the deposition of various materials. It is widely used in semiconductor manufacturing, optoelectronic devices, and MEMS.

[0003] In PECVD deposition chambers used for large-area substrates, plate heaters are typically employed for heating. However, with repeated use, these plate heaters deform under thermal stress, resulting in a structure with a convex center and sunken edges. To address this, plate heaters are usually connected using a central fixed connection and longitudinally floating edges to prevent excessive interference between the plate heater and the connection structure. However, even with this connection method, as the deformation of the plate heater increases, the floating connection has a floating limit, and excessively low surface flatness leads to decreased heating uniformity. Consequently, excessively deformed plate heaters still need to be replaced, which is detrimental to the continuous operation of the deposition chamber and reduces deposition efficiency. Utility Model Content

[0004] The purpose of this invention is to provide a PECVD plate heater with a longer lifespan.

[0005] To achieve the above objectives, this utility model provides the following technical solution:

[0006] A PECVD plate heater, comprising:

[0007] The support plate has a first side and a second side disposed opposite to each other, and a thermal resistance flange for connecting an external circuit is provided on the second side of the support plate.

[0008] The first heating component includes several first heating wires embedded in and connected to the first side of the support plate. The first heating wires are armored heating cables and are all electrically connected to the thermal resistance flange.

[0009] The second heating component includes several second heating wires embedded in and connected to the second side of the support plate. The second heating wires are all armored heating cables electrically connected to the thermal resistance flange, and the second heating component operates independently of the first heating component.

[0010] Optionally, the first side of the support plate has a centerline area, multiple inner heating areas, and an outer heating area. The centerline area is located at the centerline of the support plate extending along a first direction. The multiple inner heating areas are distributed on both sides of the centerline area. The outer heating area is located at the edge of the support plate and surrounds the multiple inner heating areas together with the centerline area. The position of the thermal resistance flange corresponds to the centerline area. Each of the first heating wires extends from the thermal resistance flange, passes through the centerline area to reach any of the inner heating areas or any of the outer heating areas, and extends through the centerline area to the thermal resistance flange after meandering inside. Each of the first heating wires operates independently.

[0011] Optionally, it also includes multiple temperature sensing couplers, at least one of the temperature sensing couplers is disposed on the first side of the support plate near a corner, for detecting the output temperature of the corresponding external heating zone, and at least one of the temperature sensing couplers is disposed in the middle of any of the internal heating zones on the first side of the support plate, for detecting the output temperature of the corresponding internal heating zone.

[0012] Optionally, it also includes a temperature sensing flange located corresponding to the centerline zone, and any of the temperature sensing couplers is electrically connected to the temperature sensing flange.

[0013] Optionally, the first side of the support plate includes two inner heating zones and two outer heating zones. The inner heating zone has a proximal end away from the thermal resistance flange along a first direction, a distal end opposite to the proximal end, and a hot wire inlet adjacent to the thermal resistance flange. The first heating wire used for heating the inner heating zone is the inner heating wire. The inner heating wire extends from the hot wire inlet of the inner heating zone into the interior of the inner heating zone, extends in a wavy manner along the first direction to a position adjacent to the distal end in the inner heating zone, then extends in a serpentine manner to a position adjacent to the proximal end in the inner heating zone, and then extends along the first direction to the hot wire inlet of the inner heating zone, connecting to the thermal resistance flange.

[0014] Optionally, each of the second heating wires is disposed opposite to each of the first heating wires.

[0015] Optionally, the surface of the support plate is further provided with multiple heat insulation grooves, which are arranged in a grid pattern with alternating horizontal and vertical directions.

[0016] Optionally, the first side of the support plate is formed with a first groove for accommodating the first heating wire, the second side of the support plate is formed with a second groove for accommodating the second heating wire, the first side of the support plate is connected with an aluminum sealing plate for closing the opening of the first groove, and the second heating wire is constrained to the second groove by bolts arranged along the second groove.

[0017] Optionally, the width of the first groove is greater than that of the first heating wire, the first heating wire having a straight portion and a bent portion, and the width of the portion of the first groove corresponding to the bent portion is greater than the width of the portion of the first groove corresponding to the straight portion.

[0018] The beneficial effects of this invention are as follows: By simultaneously heating the first and second sides of the support plate, the difference in thermal stress between the two sides is reduced, resulting in a more uniform distribution of thermal stress within the support plate. This helps suppress deformation of the support plate and facilitates its return to its original shape after thermal expansion, thus extending its service life. Furthermore, during PECVD, the plasma in the chamber generates powdery impurities, typically yellow powder, when exposed to low temperatures. Yellow powder adsorbed onto the substrate surface can cause micro-defects or foreign matter contamination in the deposited film, negatively impacting its uniformity. Excessive yellow powder generation can alter the plasma content ratio, ultimately leading to a shift in the film's elemental composition and potentially exacerbating side reactions. Ultimately, yellow powder formation reduces plasma stability, causing process fluctuations, shortening equipment lifespan, and increasing maintenance costs. This invention, by heating the support plate on both sides, improves the temperature uniformity within the chamber, preventing localized low temperatures and thus suppressing yellow powder formation, thereby improving deposition quality.

[0019] Furthermore, by setting up independently operating inner and outer heating zones, it is convenient to independently adjust the heating temperature of the inner and outer sides of the PECVD plate heater, preventing uneven internal and external temperatures caused by different heat transfer distances due to deformation of the carrier plate. By increasing the heating temperature, the increased distance caused by deformation of the carrier plate edge towards the direction away from the substrate is compensated, thereby improving the deposition quality.

[0020] Furthermore, the use of thermocouples helps to accurately detect the output temperature of each zone, facilitating precise temperature adjustment.

[0021] Furthermore, separately installing thermal resistance flanges and temperature sensing flanges to control the heating and temperature sensing on / off states allows for more comprehensive temperature monitoring. Since the heat resistance of the thermocouple's connecting wires is lower than that of armored heating cables, separate thermal resistance flanges and temperature sensing flanges help reduce damage to the thermocouple's connecting wires caused by the high temperatures generated by the convergence of multiple armored heating cables. This also helps improve the accuracy of thermocouple testing and allows for a reduction in the size of the thermal resistance flanges and temperature sensing flanges.

[0022] Furthermore, by arranging the internal heating wire in a wavy pattern as it extends toward the distal end, it helps to prevent the internal heating wire from deforming and detaching from the support plate under thermal stress.

[0023] Furthermore, the heating wires on both sides of the bearing plate are arranged in the same way, that is, the heating positions on both sides of the bearing plate are the same, which helps to suppress the deformation of the bearing plate caused by uneven distribution of thermal stress.

[0024] Furthermore, by setting up heat insulation grooves, heat diffusion is suppressed, which helps to prevent mutual interference between the output temperatures of the inner heating zone and the outer heating zone, and provides a buffer position when the support plate is deformed by heat, preventing mechanical interference caused by deformation, and facilitating the support plate to return to its original shape when the temperature drops, thereby improving the service life of the support plate.

[0025] Furthermore, constraining the heating wire with an aluminum sealing plate helps reduce the difficulty of surface cleaning and facilitates maintenance. Since the second side of the carrier plate is far from the substrate, yellow powder deposition is less likely to occur on the second heating wire, and the uneven output caused by a small amount of local yellow powder deposition has no significant impact on the deposition quality. The manufacturing cost of constraining the heating wire with bolts is low, which helps to improve the manufacturing efficiency.

[0026] Furthermore, leaving a buffer space within the groove to allow the heating wire to expand due to thermal stress helps reduce the risk of the heating wire coming off or undergoing abnormal bending and deformation.

[0027] 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

[0028] Figure 1 This is a schematic diagram of the first side structure of the PECVD plate heater after the heat insulation groove is hidden, as shown in Embodiment 1 of this utility model.

[0029] Figure 2 This is a centerline cross-sectional view of the PECVD plate heater with the heat insulation groove hidden, as shown in Embodiment 1 of this utility model.

[0030] Figure 3 This is a partial structural schematic diagram of the first groove and the first heating wire shown in Embodiment 1 of this utility model;

[0031] Figure 4 This is a schematic diagram of the first side structure of the PECVD plate heater after the heat insulation groove is hidden, as shown in Embodiment 2 of this utility model.

[0032] Legend: 1-Bearing plate, 11-Center line area, 12-Inner heating area, 13-Outer heating area, 14-First groove, 2-First heating component, 21-First heating wire, 22-Inner heating wire, 221-Straight section, 222-Bent section, 223-Bent connection section, 224-Straight connection section, 225-Through section, 23-Outer heating wire, 3-Thermal resistance flange, 41-Temperature measuring flange, 42-Temperature measuring coupler. Detailed Implementation

[0033] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0034] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0035] 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0036] Furthermore, the technical features involved in the different embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0037] The PECVD plate heater claimed in this utility model application includes a support plate 1, a first heating assembly 2, and a second heating assembly. The support plate 1 has a first side and a second side disposed opposite to each other, and a thermal resistance flange 3 for connecting to an external circuit is provided on the second side of the support plate 1. The first heating assembly 2 includes several first heating wires 21 embedded and connected to the first side of the support plate 1. The first heating wires 21 are armored heating cables and are all electrically connected to the thermal resistance flange 3. The second heating assembly includes several second heating wires embedded and connected to the second side of the support plate 1. The second heating wires are all armored heating cables electrically connected to the thermal resistance flange 3, and the second heating assembly operates independently of the first heating assembly 2.

[0038] By simultaneously heating the first and second sides of the support plate 1, the difference in thermal stress between the two sides is reduced, resulting in a more uniform distribution of thermal stress within the support plate 1. This helps suppress deformation of the support plate 1 and facilitates its return to its original shape after thermal expansion, thus extending its service life. Furthermore, during PECVD, the plasma in the chamber generates powdery impurities, typically yellow powder, when exposed to low temperatures. Yellow powder adsorbed onto the substrate surface can cause micro-defects or foreign matter contamination in the deposited film, negatively impacting its uniformity. Excessive yellow powder generation can alter the plasma composition, leading to shifts in the film's elemental composition and potentially exacerbating side reactions. Ultimately, yellow powder formation reduces plasma stability, causing process fluctuations, shortening equipment lifespan, and increasing maintenance costs. This invention, by heating the support plate 1 on both sides, improves the temperature uniformity within the chamber, preventing localized low temperatures and thus suppressing yellow powder formation, thereby improving deposition quality.

[0039] Please refer to the following examples for details.

[0040] Example 1:

[0041] Please see Figure 1 The PECVD plate heater shown in a preferred embodiment of this application includes a support plate 1, a first heating component 2, and a second heating component. The support plate 1 is constructed as a rectangular flat plate structure. When it is horizontally installed in the PECVD chamber, its upper surface is the first side surface, and its lower surface is the second side surface. The first heating component 2 is installed on the first side surface of the support plate 1, and the second heating component is installed on the second side surface of the support plate 1.

[0042] Please see Figure 1 and Figure 2The first direction is defined as the direction parallel to one edge of the support plate 1, and the second direction is defined as the direction perpendicular to the first direction. Multiple regularly arranged rectangular grooves are formed at the two edges of the support plate 1 parallel to the second direction for mounting the support plate 1. Using the centerline of the support plate 1 parallel to the first direction as the centerline of the support plate 1, the first side of the support plate 1 is divided into five regions: a centerline region 11, two inner heating regions 12, and two outer heating regions 13. These five regions are symmetrically arranged along the centerline. The centerline region 11 is a long strip including the centerline and its two sides. The two inner heating regions 12 are symmetrically arranged on both sides of the centerline region 11 and are constructed as long rectangular strips adjacent to the centerline region 11. The two outer heating regions 13 are each constructed as grooves with one side opening, which, together with the centerline region 11, surround the two inner heating regions 12. The width of the outer heating regions 13 is relatively uniform. A thermal resistance flange 3 and a temperature measuring flange 41 for connecting external circuits are installed on the support plate 1. Both the thermal resistance flange 3 and the temperature measuring flange 41 are installed on the second side of the support plate 1 and are located on the center line of the support plate 1.

[0043] The first heating assembly 2 includes multiple first heating wires 21 embedded in and connected to the first side of the support plate 1. Each first heating wire 21 is an armored heating cable, with both ends electrically connected to the thermal resistance flange 3, passing through the support plate 1 to reach the second side of the support plate 1, and used for heating the inner heating zone 12 and the outer heating zone 13, respectively. The end of the inner heating zone 12 furthest from the thermal resistance flange 3 along the first direction is designated as the near end, and the end opposite the near end as the far end. The position of the inner heating zone 12 adjacent to the thermal resistance flange 3 is designated as the hot wire inlet. The first heating wire 21 used for heating the inner heating zone 12 is designated as the inner heating wire 22, and the first heating wire 21 used for heating the outer heating zone 13 is designated as the outer heating wire 23. The inner heating wire 22 extends from the thermal resistance flange 3 to the first side of the support plate 1 and then directly enters the inner heating zone 12 from the hot wire inlet. After meandering within the inner heating zone 12, it exits the inner heating zone 12 from the hot wire inlet and connects to the thermal resistance flange 3. The internal heating wire 22 within the internal heating zone 12 includes a serpentine segment, a curved connecting portion 223, a straight connecting portion 224, and a through portion 225. The serpentine segment includes multiple straight portions 221 parallel to the second direction and arranged along the first direction, and semi-circular bends 222 connecting adjacent straight portions 221 to form a serpentine shape. Both ends of the serpentine segment are close to the centerline and are connected to two through portions 225 via the curved connecting portion 223 and the straight connecting portion 224, respectively. The through portion 225 traverses the heating wire inlet of the internal heating zone 12, connecting the inside and outside of the internal heating zone 12. The curved connecting portion 223 has a wavy structure in the middle and straight structures at both ends, connecting the distal end of the serpentine segment near the internal heating zone 12 to the adjacent through portion 225. The straight connecting portion 224 has a straight overall structure, connecting the proximal end of the serpentine segment near the internal heating zone 12 to the adjacent through portion 225. The length of the straight section 221 located near the proximal end of the hot wire inlet is greater than the length of the straight section 221 located near the distal end of the hot wire inlet, thereby compensating for the difference in heating width between the curved section 223 and the straight section 224. The external heating wire 23 longitudinally and obliquely passes through the centerline section to reach the external heating zone 13, then meanders along the external heating zone 13 in a serpentine pattern, reaching the centerline section again before extending obliquely to the corresponding position of the thermal resistance flange 3. In this embodiment, multiple internal heating wires 22 and external heating wires 23 operate independently.

[0044] Please see Figure 3 The first side surface of the support plate 1 has a first groove 14 that mates with the extending direction of the first heating wire 21 and is used to accommodate the first heating wire 21. The width of the first groove 14 is greater than that of the first heating wire 21, and the width of the portion of the first groove 14 corresponding to the bent portion 222 is greater than the width of the portion of the first groove 14 corresponding to the straight portion 221, thereby providing buffer space for the expansion and contraction of the first heating wire 21. An aluminum sealing plate is connected to the first side surface of the support plate 1 to close the opening of the first groove 14, thereby constraining the first heating wire 21 within the first groove 14.

[0045] Multiple heat insulation grooves are also formed on the first side of the support plate 1. The heat insulation grooves are arranged in a grid pattern, so that the output temperature varies significantly when the heating temperature of the inner heating zone 12 and the outer heating zone 13 is different. In other embodiments, the heat insulation grooves are usually set on the surface of the aluminum sealing plate. In this embodiment, the heat insulation grooves are set on the first side of the support plate 1 because the aluminum sealing plate is thinner and the deformation of the support plate 1 is smaller in this embodiment.

[0046] The second heating assembly includes several second heating wires embedded in and connected to the second side of the support plate 1. These second heating wires are all armored heating cables identical to the first heating wire 21 and are electrically connected to the thermal resistance flange 3. The second heating assembly operates independently of the first heating assembly 2. The second side of the support plate 1 has a second groove for accommodating the second heating wires. The arrangement of the second heating wires is exactly the same as that of the first heating wire 21, making the arrangement of the second groove identical to that of the first groove 14. However, the second heating wires are constrained to the second groove by bolts arranged along the second groove. The second side of the support plate 1 also has several heat-insulating grooves arranged in a grid pattern, used for deformation buffering of the support plate 1 and reducing surface temperature propagation efficiency.

[0047] The PECVD plate heater in this embodiment also includes multiple temperature measuring couplers 42. Two temperature measuring couplers 42 are respectively disposed at two adjacent corners of the first side of the support plate 1, corresponding to the two outer heating zones 13. Two more temperature measuring couplers 42 are respectively disposed in the two inner heating zones 12 on the first side of the support plate 1, located slightly outward from the center of the inner heating zone 12 in the second direction, and adjacent to the center of the inner heating zone 12 in the first direction. The two temperature measuring couplers 42 are disposed parallel to the second direction. In addition, the positions of the four temperature measuring couplers 42 disposed on the second side of the support plate 1 correspond one-to-one with the temperature measuring couplers 42 on the first side. Each temperature measuring coupler 42 is electrically connected to a temperature measuring flange 41. The temperature measuring flange 41 is independently controlled from the thermal resistance flange 3.

[0048] This invention extends the service life of the PECVD plate heater by using double-sided heating, suppresses the formation of yellow powder, and improves the deposition quality. By adjusting the heating output temperature in different zones, it compensates for the varying degrees of deformation occurring at different locations of the PECVD plate heater, ensuring the uniformity of heating of the substrate to be deposited.

[0049] Example 2:

[0050] Please see Figure 1 and Figure 4The difference between this embodiment and Embodiment 1 lies only in that this embodiment sets up four internal heating zones 12 and four external heating zones 13 with identical structures. Two internal heating zones 12 on the same side are arranged along the first direction with a gap in the middle, and the four external heating zones 13 correspond to the four internal heating zones 12 and are located outside the internal heating zones 12. In this embodiment, the temperature measuring flange 41 is set at a position near the center of the support plate 1, and the two thermal resistance flanges 3 are both set on the centerline of the support plate 1, and correspond to the middle position of the two internal heating zones 12 in the first direction. The internal heating wire 22 in the internal heating zone 12 does not include the curved connecting part 223, and both ends of the serpentine section are connected to the passing part 225 through the straight connecting part 224. The two ends of the external heating wire 23 pass through the centerline part and the gap between the two internal heating zones 12 arranged along the first direction, respectively. A temperature measuring thermocouple 42 is set in each internal heating zone 12 and external heating zone 13. Setting up multiple thermal resistance flanges 3 helps to reduce the total amount of thermal resistance flanges 3 and external heating wires 23, and reduce the temperature at the thermal resistance flanges 3.

[0051] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0052] The embodiments described above are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model patent should be determined by the appended claims.

Claims

1. A PECVD plate heater, characterized in that, include: The support plate (1) has a first side and a second side disposed opposite to each other, and a thermal resistance flange (3) for connecting an external circuit is provided on the second side of the support plate (1); The first heating component (2) includes several first heating wires (21) embedded in the first side of the support plate (1), the first heating wires (21) being armored heating cables and all electrically connected to the thermal resistance flange (3). The second heating component includes several second heating wires embedded in the second side of the support plate (1). The second heating wires are all armored heating cables electrically connected to the thermal resistance flange (3), and the second heating component operates independently of the first heating component (2).

2. The PECVD plate heater as described in claim 1, characterized in that, The first side of the support plate (1) has a center line area (11), a plurality of inner heating areas (12) and an outer heating area (13). The center line area (11) is located at the center line of the support plate (1) extending along the first direction. The plurality of inner heating areas (12) are distributed on both sides of the center line area (11). The outer heating area (13) is located at the edge of the support plate (1) and surrounds the plurality of inner heating areas (12) together with the center line area (11). The position of the thermal resistance flange (3) corresponds to the center line area (11). Each of the first heating wires (21) extends from the thermal resistance flange (3), passes through the center line area (11) to reach any of the inner heating areas (12) or any of the outer heating areas (13), and extends through the center line area (11) to the thermal resistance flange (3) after meandering inside. Each of the first heating wires (21) operates independently.

3. The PECVD plate heater as described in claim 2, characterized in that, It also includes multiple temperature measuring couplers (42), at least one of the temperature measuring couplers (42) is disposed on the first side of the support plate (1) near the corner, for detecting the output temperature of the corresponding external heating zone (13), and at least one of the temperature measuring couplers (42) is disposed in the middle of any of the internal heating zones (12) on the first side of the support plate (1), for detecting the output temperature of the corresponding internal heating zone (12).

4. The PECVD plate heater as described in claim 3, characterized in that, It also includes a temperature measuring flange (41) located in the center line area (11), and any of the temperature measuring couplers (42) is electrically connected to the temperature measuring flange (41).

5. The PECVD plate heater as described in claim 4, characterized in that, The first side of the support plate (1) includes two inner heating zones (12) and two outer heating zones (13). The inner heating zone (12) has a proximal end away from the thermal resistance flange (3) along a first direction, a distal end opposite to the proximal end, and a hot wire inlet adjacent to the thermal resistance flange (3). The first heating wire (21) used for heating the inner heating zone (12) is the inner heating wire (22). The inner heating wire (22) extends from the hot wire inlet of the inner heating zone (12) into the interior of the inner heating zone (12), extends in a wavy manner along the first direction to a position adjacent to the distal end in the inner heating zone (12), then extends in a serpentine manner to a position adjacent to the proximal end in the inner heating zone (12), and then extends along the first direction to the hot wire inlet of the inner heating zone (12) and connects to the thermal resistance flange (3).

6. The PECVD plate heater as described in claim 1, characterized in that, Each of the second heating wires is arranged opposite to each of the first heating wires (21).

7. The PECVD plate heater as described in claim 1, characterized in that, The surface of the bearing plate (1) also has multiple heat insulation grooves, which are arranged in a grid pattern.

8. The PECVD plate heater as described in claim 1, characterized in that, The first side of the support plate (1) is formed with a first groove (14) for accommodating the first heating wire (21), and the second side of the support plate (1) is formed with a second groove for accommodating the second heating wire. The first side of the support plate (1) is connected with an aluminum sealing plate for closing the opening of the first groove (14). The second heating wire is constrained to the second groove by bolts arranged along the second groove.

9. The PECVD plate heater as described in claim 8, characterized in that, The width of the first groove (14) is greater than that of the first heating wire (21). The first heating wire (21) has a straight portion (221) and a bent portion (222). The width of the portion of the first groove (14) corresponding to the bent portion (222) is greater than the width of the portion of the first groove (14) corresponding to the straight portion (221).

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