Electrostatic chuck and semiconductor process equipment

Abstract

The invention discloses an electrostatic chuck and semiconductor process equipment, and relates to the technical field of semiconductor preparation, the disclosed electrostatic chuck comprises a base, a bearing disc, a cooling part and a temperature adjusting assembly, the bearing disc covers the opening end of the base, an accommodating cavity is defined by the bearing disc and the base, and a heating part is arranged in the bearing disc. The cooling component is arranged in the containing cavity, a heat buffering gap is formed between the bearing disc and the cooling component, the temperature adjusting assembly comprises a heat resisting sheet, and the heat resisting sheet is arranged in the heat buffering gap and can move in the heat buffering gap in the first direction so as to adjust the heat transfer rate between the bearing disc and the cooling component. Through the mode of adjusting the heat transfer rate between the bearing disc and the cooling component, the temperature adjusting precision of the bearing disc can be improved, meanwhile, the heating efficiency of the heating piece can be improved, and the energy consumption of the heating piece can be reduced.

Description

Technical Field

[0001] The present application relates to the field of semiconductor manufacturing technology, and in particular to an electrostatic chuck and semiconductor process equipment. Background Art

[0002] Electrostatic chucks are widely used in semiconductor production processes. For example, in processes such as plasma etching, physical vapor deposition, and chemical vapor deposition of wafers, electrostatic chucks can be used to fix and support the wafer to prevent the wafer from moving or misaligning during the process. At the same time, the temperature of the wafer surface can also be controlled.

[0003] The electrostatic chuck is mainly composed of two parts: a ceramic disk and a metal base. The ceramic disk is used to adsorb the wafer. A heater is provided in the ceramic disk, which is mainly used to heat the adsorbed wafer. A cooling component is provided in the metal base, which can cool the ceramic disk and the wafer. In the related art, the temperature of the ceramic disk and the wafer is adjusted by the cooperation of the cooling component and the heater. However, in the scenario where the wafer needs to be heated, since the cooling component will take away a considerable amount of heat from the ceramic disk, the heater needs to make up for this part of the lost heat while heating the ceramic disk, which results in a large energy consumption of the heater, and also causes the ceramic disk and the wafer to be heated to the preset temperature for a long time. Summary of the invention

[0004] The present application discloses an electrostatic chuck and semiconductor process equipment to solve the problem of high energy consumption when a heater is used to heat a ceramic disc in the related art.

[0005] In order to solve the above technical problems, this application is implemented as follows: In a first aspect, an embodiment of the present application discloses an electrostatic chuck, wherein the disclosed electrostatic chuck includes a base, a carrier plate, a cooling component, and a temperature adjustment assembly; The carrier plate cover is arranged at the open end of the base and forms a receiving cavity with the base, and a heating element is arranged inside the carrier plate; The cooling component is arranged in the accommodating cavity, and a heat buffer gap is provided between the carrier plate and the cooling component along a first direction. The temperature adjustment component comprises a heat insulating sheet, which is arranged in the heat buffer gap and can move in the heat buffer gap along the first direction to adjust the heat transfer rate between the carrier plate and the cooling component; Wherein, the first direction is perpendicular to the disk surface of the supporting disk.

[0006] In a second aspect, an embodiment of the present application discloses a semiconductor process equipment, wherein the disclosed semiconductor process equipment includes a process chamber and the above-mentioned electrostatic chuck, wherein the electrostatic chuck is disposed in the process chamber.

[0007] The technical solution adopted in this application can achieve the following technical effects: The electrostatic chuck disclosed in the embodiment of the present application improves the related art. The disclosed electrostatic chuck includes a base, a carrier plate, a cooling component and a temperature adjustment component. The carrier plate cover is arranged at the open end of the base and forms a receiving cavity with the base. A heating element is arranged inside the carrier plate, and the cooling component is arranged in the receiving cavity. There is a thermal buffer gap between the carrier plate and the cooling component. The temperature of the carrier plate and the adsorbed wafer can be adjusted by heat transfer between the carrier plate and the cooling component. The heat insulation sheet of the temperature adjustment component is arranged in the thermal buffer gap and can move in the thermal buffer gap along the first direction. When the carrier plate and the wafer need to be cooled down, the heat insulation sheet can be controlled to move upward and close to the carrier plate. Since the air content between the heat insulation sheet and the carrier plate is reduced, the thermal resistance is reduced, so that the heat transfer rate between the carrier plate and the cooling component is increased, and more heat can be transferred from the carrier plate to the cooling component; when the carrier plate and the wafer need to be heated up, the heat insulation sheet can be controlled to move downward and close to the cooling component. Since the air content between the heat insulation sheet and the carrier plate is increased, the thermal resistance is increased, and the heat transfer rate between the carrier plate and the cooling component is reduced, and only less heat is transferred from the carrier plate to the cooling component. By adjusting the heat transfer rate between the carrier plate and the cooling component, on the one hand, the temperature adjustment accuracy of the carrier plate can be improved, and on the other hand, the heating efficiency of the heating element can be improved and the energy consumption of the heating element can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 A schematic cross-sectional structure diagram of an electrostatic chuck disclosed in an embodiment of the present application; Figure 2 This is a schematic diagram of the structure of the temperature adjustment component disclosed in the embodiment of the present application; Figure 3 A schematic diagram of the structure of an annular adjustment area composed of multiple heat insulation sheets disclosed in an embodiment of the present application; Figure 4 This is a schematic diagram of the structure of the bottom of the base disclosed in the embodiment of the present application; Figure 5 This is a schematic diagram of the structure of the cooling plate disclosed in the embodiment of the present application; Figure 6 This is a schematic diagram of the structure of the driving shaft disclosed in the embodiment of the present application; Figure 7 It is a schematic diagram of the structure of the driven shaft disclosed in the embodiment of the present application; Figure 8 A schematic diagram of the structure of the limit block disclosed in the embodiment of the present application; Fig. 9 It is a schematic diagram of the assembly structure of the carrier plate and the metal connecting part disclosed in the embodiment of the present application; Fig.10 A schematic diagram of the structure of the carrier plate disclosed in the embodiment of the present application; Fig.11 This is a schematic diagram of the assembly structure of the carrier plate and the base disclosed in the embodiment of the present application.

[0009] Description of reference numerals: 101-first direction, 110-base, 111-threaded hole, 112-annular carrier, 120-carrying plate, 121-heating element, 122-disc body, 1221-flow hole, 123-metal connecting part, 1231-fluid channel, 130-cooling component, 131-cooling plate, 1311-first avoidance hole, 132-cooling pipeline, 140-temperature adjustment component, 141-thermal insulation plate, 142-annular adjustment area, 143-threaded shaft, 1431-driving shaft, 1432-driven shaft, 144-limiting block, 1441-through hole, 150-thermal buffer gap, 160-thermal insulation ring, 170-elastic part, 180-sealing structure. DETAILED DESCRIPTION

[0010] In order to make the purpose, technical solution and advantages of the present application clearer, the technical solution of the present application will be clearly and completely described below in combination with the specific embodiments of the present application and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

[0011] The terms "first", "second", etc. in the specification and claims of this application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. are generally of the same type, and the number of objects is not limited. For example, the first object can be one or more.

[0012] The technical solutions disclosed in various embodiments of the present application are described in detail below in conjunction with the accompanying drawings.

[0013] An electrostatic chuck is a fixture that uses electrostatic force to adsorb and fix the workpiece on the chuck surface. Compared with traditional mechanical chucks and vacuum chucks, electrostatic chucks are widely used in precision machining scenarios due to their less damage to the workpiece and higher precision. They are especially widely used in semiconductor manufacturing processes, such as plasma etching (ETCH), physical vapor deposition (PVD), and chemical vapor deposition (CVD).

[0014] Taking wafer processing as an example, the electrostatic chuck can adsorb the wafer to be processed on its surface through the principle of electrostatic adsorption. When the powered electrostatic chuck approaches the wafer with uniform internal charge distribution, the positive and negative charges inside the wafer will move to the electrode end with opposite polarity respectively, and the wafer will be firmly adsorbed to the surface of the electrostatic chuck through the Coulomb force generated by the attraction of opposite charges.

[0015] In the semiconductor process, the temperature control of the wafer is the key to the yield rate. Therefore, it is necessary to heat or dissipate the heat of the wafer adsorbed by the electrostatic chuck by the cooperation of the heater and the cooling component, so as to control the temperature of the wafer. However, in the scenario where the wafer needs to be heated, since the cooling component will take away a considerable amount of heat from the electrostatic chuck, the heater needs to make up for this part of the lost heat while heating the electrostatic chuck, which results in a large energy consumption of the heater, and also causes the electrostatic chuck and the wafer to be heated to the preset temperature for a long time.

[0016] Based on the above questions, please refer to Figures 1 to 11 , the embodiment of the present application discloses an electrostatic chuck, and the disclosed electrostatic chuck may include a base 110, a carrier plate 120, a cooling component 130 and a temperature adjustment component 140. Among them, the base 110 is the structural foundation of the electrostatic chuck, and the base 110 may be made of aluminum alloy. The base 110 is provided with an open end, and the carrier plate 120 is covered on the open end of the base 110, and forms a receiving cavity with the base 110. The connection method between the carrier plate 120 and the base 110 may be bonding, bolting, etc. The carrier plate 120 is used to adsorb wafers. The carrier plate 120 is a multi-layer structure, and the outer layer may be made of ceramic material. The interior of the carrier plate 120 is provided with an adsorption electrode layer. When the adsorption electrode layer is energized, it can form an electrostatic field on the surface of the carrier plate 120 and adsorb the wafer on the surface of the carrier plate 120.

[0017] A heating element 121 is also provided inside the carrier plate 120. The heating element 121 can be sintered with the ceramic material of the outer layer. When the heating element 121 is powered, the surface of the carrier plate 120 and the adsorbed wafers can be heated. A cooling component 130 is provided in the accommodating cavity. The cooling component 130 can be a liquid cooling mechanism, an air cooling mechanism, etc. The temperature of the carrier plate 120 and the adsorbed wafers can be adjusted by heat transfer between the carrier plate 120 and the cooling component 130.

[0018] like Figure 1As shown, a first direction 101 is defined to be perpendicular to the disk surface of the carrier plate 120. Along the first direction 101, there is a thermal buffer gap 150 between the carrier plate 120 and the cooling component 130, and the carrier plate 120 and the cooling component 130 can achieve heat exchange through the thermal buffer gap 150. The greater the heat transfer rate between the carrier plate 120 and the cooling component 130, the more heat will be transferred from the carrier plate 120 to the cooling component 130. If the heat generated by the heating element 121 is less than the heat transferred away, the surface temperature of the carrier plate 120 will drop, and the temperature of the adsorbed wafer will also drop accordingly; assuming that the heating power of the above-mentioned heating element 121 remains unchanged, the smaller the heat transfer rate between the carrier plate 120 and the cooling component 130, the less heat will be transferred from the carrier plate 120 to the cooling component 130. If the heat generated by the heating element 121 is greater than the heat transferred away, the surface temperature of the carrier plate 120 will increase, and the temperature of the adsorbed wafer will also increase accordingly.

[0019] According to the above working principle, in the scenario where the carrier plate 120 and the wafer adsorbed thereon need to be quickly heated up or cooled down, the heating efficiency or cooling efficiency of the carrier plate 120 can be flexibly adjusted by adjusting the heat transfer rate between the carrier plate 120 and the cooling component 130. In an optional embodiment of the application, the heat transfer rate between the carrier plate 120 and the cooling component 130 can be adjusted by using a temperature adjustment component 140. Specifically, the temperature adjustment component 140 can include a heat insulation sheet 141. The heat insulation sheet 141 can be made of materials such as micro-nano ceramic fibers and carbon fiber reinforced carbon aerogels. The heat insulation sheet 141 can be circular, polygonal, etc. The heat insulation sheet 141 is arranged in the thermal buffer gap 150. Along the first direction 101, the projection of the heat insulation sheet 141 can completely cover the carrier plate 120, or only cover a partial area of ​​the carrier plate 120.

[0020] The number of the heat insulation sheets 141 may be one, two or more. When the number of the heat insulation sheets 141 is only one, the projection of the heat insulation sheet 141 along the first direction 101 may completely cover the above-mentioned carrier plate 120, or may only cover a partial area of ​​the carrier plate 120; similarly, when the number of the heat insulation sheets 141 is two or more, the two or more heat insulation sheets 141 may jointly cover the carrier plate 120, or may only cover a partial area of ​​the carrier plate 120. The specific number of the heat insulation sheets 141 and the coverage area on the carrier plate 120 may be selected according to the temperature regulation requirements of the carrier plate 120 and the wafer, and the embodiments of the present application do not limit this.

[0021] The heat insulating sheet 141 can move in the heat buffer gap 150 along the first direction 101, and can be driven by a driving source such as a motor or a cylinder. Since the heat buffer gap 150 is filled with a large amount of air, and the thermal resistance of the air is large, when the heat insulating sheet 141 moves upward and approaches the carrier plate 120, a part of the air between the carrier plate 120 and the heat insulating sheet 141 will be squeezed out, and the air content will be reduced, so that the thermal resistance between the carrier plate 120 and the heat insulating sheet 141 will be reduced, and more heat will be transferred to the heat insulating sheet 141 from the area corresponding to the carrier plate 120 and the heat insulating sheet 141, and then exported to the cooling component 130 through the heat insulating sheet 141. Without considering the heating by the heating element 121, the temperature of the area corresponding to the carrier plate 120 and the heat insulating sheet 141 will be reduced. When the heat insulating sheet 141 is in contact with the carrier plate 120, the air content between the carrier plate 120 and the heat insulating sheet 141 approaches zero. At this time, the thermal resistance between the carrier plate 120 and the heat insulating sheet 141 is the smallest. This adjustment method can be applied to the scenario where the carrier plate 120 and the wafer need to be cooled down quickly.

[0022] When the heat insulating sheet 141 moves downward and away from the carrier plate 120, the gap between the carrier plate 120 and the heat insulating sheet 141 increases, and the air content increases, so that the thermal resistance between the carrier plate 120 and the heat insulating sheet 141 increases, and the area corresponding to the carrier plate 120 and the heat insulating sheet 141 will have less heat transferred to the heat insulating sheet 141, and then exported to the cooling component 130 through the heat insulating sheet 141. Without considering the heating of the heating element 121, the temperature of the area corresponding to the carrier plate 120 and the heat insulating sheet 141 will increase. When the heat insulating sheet 141 is attached to the cooling component 130, the air content between the carrier plate 120 and the heat insulating sheet 141 increases to the maximum, and at this time, the thermal resistance between the carrier plate 120 and the heat insulating sheet 141 is the maximum. This adjustment method can be applied to scenarios where the carrier plate 120 and the wafer need to be heated up quickly, which can improve the heating efficiency of the heating element 121 to a certain extent, and the energy consumption required for the heating element 121 to heat the carrier plate 120 and the wafer to a preset temperature will also be reduced.

[0023] By adding a heat insulating sheet 141 between the carrier plate 120 and the cooling component 130 , the accuracy and efficiency of temperature regulation are improved to a certain extent compared to a solution of only using the heating element 121 and the cooling component 130 to regulate the temperature of the carrier plate 120 .

[0024] It should be noted that, along the first direction 101, the heat insulating sheet 141 has a first surface close to the carrier plate 120 and a second surface away from the carrier plate 120, and the second surface of the heat insulating sheet 141 and the cooling component 130 are heat-conductively matched. For example, the second surface of the heat insulating sheet 141 and the cooling component 130 can be connected by a material with low thermal resistance such as metal to achieve good thermal conductivity. The heat insulating sheet 141 moves in the heat buffer gap 150 along the first direction 101, which actually adjusts the heat transfer rate between the heat insulating sheet 141 and the carrier plate 120. However, since the heat insulating sheet 141 and the cooling component 130 have good thermal conductivity, from the perspective of heat transfer, the heat insulating sheet 141 can be regarded as a part of the cooling component 130. In other words, adjusting the heat transfer rate between the heat insulating sheet 141 and the carrier plate 120 can be equivalent to adjusting the heat transfer rate between the carrier plate 120 and the cooling component 130.

[0025] In addition, a heat insulating sheet 141 is provided in the heat buffer gap 150. The heat insulating sheet 141 itself has a large thermal resistance. This is because when the carrier plate 120 is heating the wafer, if too much heat is transferred to the cooling component 130 through a material with a smaller thermal resistance, the heating efficiency of the carrier plate 120 will be reduced and the energy consumption will be increased.

[0026] From the above, it can be known that the electrostatic chuck disclosed in the embodiment of the present application improves the relevant technology. By setting a heat insulation sheet 141 that can move along the first direction 101 in the thermal buffer gap 150, when it is necessary to cool down the carrier plate 120 and the wafer, the heat insulation sheet 141 can be controlled to move upward and close to the carrier plate 120. Since the air content between the heat insulation sheet 141 and the carrier plate 120 is reduced, the thermal resistance is reduced, so that the heat transfer rate between the carrier plate 120 and the cooling component 130 is increased, and more heat can be transferred from the carrier plate 120 to the cooling component 130; when it is necessary to heat up the carrier plate 120 and the wafer, the heat insulation sheet 141 can be controlled to move downward and close to the cooling component 130. Since the air content between the heat insulation sheet 141 and the carrier plate 120 is increased, the thermal resistance is increased, and the heat transfer rate between the carrier plate 120 and the cooling component 130 is reduced, and only a small amount of heat is transferred from the carrier plate 120 to the cooling component 130. By adjusting the heat transfer rate between the carrier plate 120 and the cooling component 130 , on the one hand, the temperature adjustment accuracy of the carrier plate 120 can be improved, and on the other hand, the heating efficiency of the heating element 121 can be improved and the energy consumption of the heating element 121 can be reduced.

[0027] In the actual process, the temperature uniformity of the surface of the carrier plate 120 will directly affect the temperature uniformity of the wafer surface, and the temperature uniformity of the wafer surface will have a greater impact on the uniformity of the process. Figure 1 and Figure 3 As shown, the number of the heat insulation sheets 141 can be multiple, and the projections of the multiple heat insulation sheets 141 along the first direction 101 cover at least part of the carrier disc 120, and the multiple heat insulation sheets 141 respectively cover different local areas of the carrier disc 120. When the temperature distribution problem on the surface of the carrier disc 120 is uneven, the temperature of the local area of ​​the carrier disc 120 can be adjusted by adjusting the heat transfer rate of the local area between the carrier disc 120 and the cooling component 130. The local area can correspond to the area of ​​the carrier disc 120 where the temperature is too high or too low. In addition, the multiple heat insulation sheets 141 can be individually controlled by the driving source, which further improves the flexibility of the temperature adjustment process.

[0028] It should be noted that the disk surface of the carrier disk 120 can be divided into multiple local areas, and the projections of the multiple thermal insulation sheets 141 along the first direction 101 can cover the entire disk surface of the carrier disk 120, or can only cover part of the disk surface of the carrier disk 120. For example, the projections of the multiple thermal insulation sheets 141 along the first direction 101 can only cover the central area, edge area, left half area or right half area of ​​the disk surface of the carrier disk 120.

[0029] It should be supplemented that, when there is only one thermal insulation sheet 141, the projection of the thermal insulation sheet 141 along the first direction 101 can completely cover the above-mentioned carrier plate 120, or only cover a local area of ​​the carrier plate 120. When the projection of the thermal insulation sheet 141 completely covers the above-mentioned carrier plate 120, the overall temperature of the carrier plate 120 can be adjusted. When the projection of the thermal insulation sheet 141 only covers a local area of ​​the carrier plate 120, the temperature of the local area of ​​the carrier plate 120 can be adjusted.

[0030] like Figure 3 As shown, the heating element 121 inside the carrier plate 120 may be an annular structure, and the heating element 121 may be arranged to extend along the circumference of the carrier plate 120. Considering that the carrier plate 120 is more likely to have a problem of uneven temperature distribution in the area where the heating element 121 is located, a plurality of heat insulation sheets 141 may also be arranged in the heat buffer gap 150 at intervals along the circumference of the carrier plate 120, so as to perform targeted adjustment on the temperature uniformity of the area where the heating element 121 is located.

[0031] In an optional embodiment of the present application, Figure 3As shown, multiple heat insulation sheets 141 can be arranged at intervals along the circumference of the carrier plate 120, and form multiple mutually nested annular adjustment areas 142, and the diameters of the multiple annular adjustment areas 142 increase from the inside to the outside. For each annular adjustment area 142, it is formed by multiple fan-shaped heat insulation sheets 141 arranged at intervals along the circumference of the carrier plate 120. Each heat insulation sheet 141 can be moved separately, and the division accuracy of the temperature adjustment area is further improved. Along the first direction 101, the projections of the multiple annular adjustment areas 142 cover the carrier plate 120 together, so that the carrier plate 120 can be divided into multiple temperature adjustable areas, and each temperature adjustable area can be adjusted separately.

[0032] For example, Figure 3 As shown, the number of the annular adjustment areas 142 may be four, and correspondingly, the carrier plate 120 is also divided into four temperature-adjustable areas, and the projections of the four annular adjustment areas 142 along the first direction 101 jointly cover the carrier plate 120 .

[0033] The temperature adjustment assembly 140 may include a drive mechanism and a heat insulating sheet 141, wherein the drive mechanism is connected to the heat insulating sheet 141 to drive the heat insulating sheet 141 to move in the heat buffer gap 150 along the first direction 101. The drive mechanism may specifically include a drive source, which may be a motor, a cylinder, a hydraulic cylinder, etc.

[0034] In a specific embodiment of the present application, Figures 1 to 4 As shown, the drive mechanism may include a threaded shaft 143, Figure 4 1 is a schematic diagram of the structure of the bottom of the base 110. The bottom of the base 110 is provided with a plurality of threaded holes 111. One end of the threaded shaft 143 can pass through the threaded hole 111 and extend into the thermal buffer gap 150, and is connected to the thermal insulation sheet 141. The threaded shaft 143 can be connected to the second surface of the thermal insulation sheet 141 away from the carrier plate 120, and the specific connection method can be bonding, riveting, etc. The threaded shaft 143 can be made of a material with good thermal conductivity such as metal, and the heat transferred from the carrier plate 120 to the thermal insulation sheet 141 can be conducted to the base 110 and the cooling component 130 through the threaded shaft 143.

[0035] The threaded shaft 143 is threadedly matched with the threaded hole 111. When the threaded shaft 143 is rotated, the threaded shaft 143 will move up and down relative to the threaded shaft 143, thereby driving the heat insulation sheet 141 to move in the heat buffer gap 150 along the first direction 101. The threaded shaft 143 and the threaded hole 111 are threadedly matched to drive the heat insulation sheet 141 to move, which has a simple structure and good durability. The threaded shaft 143 can be rotated manually or driven by a motor.

[0036] The number of threaded shafts 143, threaded holes 111 and heat insulation sheets 141 is equal and one-to-one corresponding. For example, Figure 3 As shown, a plurality of heat insulation sheets 141 are arranged along the circumference of the carrier plate 120, and form a plurality of mutually nested annular adjustment areas 142. Since each heat insulation sheet 141 requires a threaded shaft 143 for control, correspondingly, the bottom of the base 110 is provided with Figure 4 The multiple threaded holes 111 are shown, and the multiple threaded holes 111 are also arranged along the circumference of the carrier plate 120 .

[0037] like Figure 1 and Figure 5 As shown, the cooling component 130 may include a cooling plate 131 and a cooling pipeline 132. The cooling plate 131 is arranged in the accommodating cavity. The cooling plate 131 includes a first end face and a second end face opposite to each other along the first direction 101. The first end face and the carrier plate 120 have the above-mentioned thermal buffer gap 150, and the second end face is close to the bottom of the base 110. The cooling pipeline 132 is arranged on the base 110 and the cooling plate 131. The cooling pipeline 132 can be arranged on the inner wall of the base 110 or buried in the structural member of the base 110. Similarly, the cooling pipeline 132 can be arranged on the surface of the cooling plate 131 or extend into the interior of the cooling plate 131. The end of the cooling pipeline 132 is connected to the cooling fluid source. The cooling fluid source realizes heat exchange with the base 110 and the cooling plate 131 through the cooling pipeline 132, thereby preventing the base 110 from being overheated.

[0038] The threaded shaft 143 will pass through the cooling plate 131 during installation, so the cooling plate 131 is also provided with a through hole for the threaded shaft 143 to pass through. In addition, the outer layer of the carrier plate 120 can be AL2O3 ceramic, ALN ceramic, etc. The carrier plate 120 is embedded with a heating element 121 and an adsorption electrode layer. The heating element 121 and the adsorption electrode layer will lead out connection terminals on the side of the carrier plate 120 close to the base 110, and are connected to an external power supply through the connection terminals. For the convenience of electrical connection, electrical connection through holes are provided on the heat insulation sheet 141, the base 110 and the cooling plate 131.

[0039] like Figure 1 , Figure 2 , Figures 5 to 7 As shown, the threaded shaft 143 may include a driving shaft 1431 and a driven shaft 1432, the driving shaft 1431 is threadedly matched with the threaded hole 111, the cooling plate 131 is provided with a first avoidance hole 1311, the first end of the driven shaft 1432 is connected to the end of the threaded shaft 143, the second end of the driven shaft 1432 passes through the first avoidance hole 1311 and extends into the heat buffer gap 150, and is connected to the heat insulation sheet 141. The cross section of the driven shaft 1432 along its own axial direction can be designed to be a regular hexagon, a spline type, etc., such as Figure 5 and Figure 7 As shown, the cross-section of the driven shaft 1432 is a regular hexagon, and correspondingly, the shape of the first avoidance hole 1311 is also a regular hexagon, so that the driven shaft 1432 can be limited by the first avoidance hole 1311, and the driving shaft 1431 and the driven shaft 1432 will not rotate at the same time. Only the driving shaft 1431 will rotate relative to the threaded hole 111, thereby driving the driven shaft 1432 and the heat insulation plate 141 to move along the first direction 101.

[0040] The driving shaft 1431 can be made of a relatively soft resin material, which can reduce the friction between the driving shaft 1432 and the driven shaft 1432. The driving shaft 1431 can be driven by a motor, and a corresponding connection hole can be processed at the bottom of the driving shaft 1431 for easy assembly.

[0041] like Figure 1 , Figure 2 , Figure 8 As shown, the temperature regulating assembly 140 may further include a limit block 144, which is disposed in the threaded hole 111 and cooperates with the end of the driving shaft 1431 facing away from the driven shaft 1432 to prevent the driving shaft 1431 from escaping from the threaded hole 111. The limit block 144 and the threaded hole 111 may be assembled by means of snap connection, bonding, or the like.

[0042] When the driving shaft 1431 is driven to rotate by a driving source such as a motor, in order to avoid interference between the driving source and the limit block 144, a through hole 1441 can be set on the limit block 144, and the through hole 1441 can be passed through by the driving source, and the driving source can drive the driving shaft 1431 to rotate relative to the threaded hole 111.

[0043] In the related art, the carrier disc 120 and the base 110 are bonded by glue, and the temperature resistance of the glue layer is limited. At high temperatures, the glue layer is easily invalidated, resulting in the electrostatic chuck being unable to be used normally. Based on the above problems, in an embodiment of the present application, the carrier disc 120 may include a disc body 122 and a metal connecting portion 123. The disc body 122 is covered at the open end of the base 110 and forms a receiving cavity with the base 110. The metal connecting portion 123 is arranged in the receiving cavity. At least a portion of the metal connecting portion 123 is welded and fixed to the surface of the disc body 122 close to the receiving cavity. The specific welding method may be electric fusion welding, laser welding, etc. The metal connecting portion 123 may be made of metal materials that can be welded with ceramics, such as MO, AL, and Al-based silicon carbide.

[0044] The base 110 can be connected to the metal connection part 123 by fasteners, and the fasteners can be screws, rivets, etc., so that the base 110 and the disk body 122 can be stably assembled. Exemplarily, the metal connection part 123 can be a disk-mounted structure, and a plurality of bolt holes are arranged on the edge of the metal connection part 123. Bolts are inserted from the back of the base 110 and finally extend into the bolt holes to achieve the assembly of the base 110 and the disk body 122.

[0045] The heat buffer gap 150 is provided between the first end surface of the cooling disk 131 and the metal connection part 123, and the disk body 122 can exchange heat with the cooling disk 131 through the metal connection part 123. The heat insulation sheet 141 can be arranged between the cooling disk 131 and the metal connection part 123. Figure 1 The heat insulation sheet 141 is shown in the highest position. At this time, the first surface of the heat insulation sheet 141 is in close contact with the metal connection part 123, and the heat is fully transferred. In this case, the thermal resistance is minimum, and the temperature of the corresponding area on the surface of the disk body 122 is low. If the heat insulation sheet 141 is moved downward, the heat insulation sheet 141 and the metal connection part 123 are no longer in contact, and the air content in the gap between the heat insulation sheet 141 and the metal connection part 123 increases, and the thermal resistance increases. The lower the position of the heat insulation sheet 141, the more air content there is, the greater the thermal resistance, and the temperature of the corresponding area on the surface of the disk body 122 will increase.

[0046] like Figure 1 As shown, the electrostatic chuck further includes a heat-insulating ring 160, which is disposed at the edge of the thermal buffer gap 150, and the two opposite end faces of the heat-insulating ring 160 are respectively in contact with the cooling plate 131 and the metal connecting portion 123. The heat-insulating ring 160 can cushion the metal connecting portion 123 to prevent the metal connecting portion 123 from directly contacting the base 110, thereby preventing the base 110 from overheating.

[0047] like Figure 1 As shown, since the height of the heat insulating ring 160 is not adjustable, in order to make the heat insulating ring 160 stably contact the cooling plate 131 and the metal connecting portion 123, an elastic member 170 can be provided between the second end surface of the cooling plate 131 and the base 110. The elastic member 170 can be a member capable of storing elastic potential energy, such as a metal spring or a silicone spring. The elastic member 170 can apply an elastic preload force to the cooling plate 131, so that the cooling plate 131 can be stably pressed against the heat insulating ring 160.

[0048] like Figure 1As shown, an annular carrier 112 is extended from the inner wall of the base 110 near the opening end, and the annular carrier 112 is arranged opposite to the edge of the metal connecting part 123 to support the metal connecting part 123. In order to improve the sealing inside the electrostatic chuck, a sealing structure 180 can be arranged between the annular carrier 112 and the metal connecting part 123, and the sealing structure 180 can be respectively abutted against the annular carrier 112 and the metal connecting part 123. The sealing structure 180 can be specifically a sealing gasket, a glue-filled sealing layer, etc.

[0049] like Figures 9 to 11 As shown, the metal connection part 123 is provided with a fluid channel 1231, and the fluid channel 1231 is connected to a fluid heat-conducting medium source, which can be a helium source. A flow hole 1221 is provided on the end surface of the disk body 122 for adsorbing the wafer, and the flow hole 1221 is connected to the fluid channel 1231. The fluid heat-conducting medium source is connected to the flow hole 1221 through the fluid channel 1231. The fluid heat-conducting medium can be ejected through the flow hole 1221 and flow on the surface of the wafer, thereby transferring heat to the wafer. In addition, the fluid heat-conducting medium source is connected to the fluid channel 1231 of the metal connection part 123 through a pipeline. To facilitate the layout of the pipeline, mounting holes for the pipeline to pass through can be provided on the base 110, the cooling disk 131 and the thermal insulation sheet 141.

[0050] Please refer to Figures 1 to 11 The embodiment of the present application also discloses a semiconductor process equipment, and the disclosed semiconductor process equipment includes the electrostatic chuck mentioned above, and the electrostatic chuck is arranged in the process chamber to adsorb and adjust the temperature of the wafer entering the process chamber.

[0051] As described above, the electrostatic chuck disclosed in the embodiment of the present application improves the related art. The disclosed electrostatic chuck includes a base 110, a carrier plate 120, a cooling component 130 and a temperature adjustment component 140. The carrier plate 120 is covered at the open end of the base 110 and forms a receiving cavity with the base 110. A heating element 121 is provided inside the carrier plate 120, and the cooling component 130 is arranged in the receiving cavity. A thermal buffer gap 150 is provided between the carrier plate 120 and the cooling component 130. The temperature of the carrier plate 120 and the adsorbed wafer can be adjusted by heat transfer between the carrier plate 120 and the cooling component 130. The thermal insulation sheet 141 of the temperature regulating assembly 140 is arranged in the thermal buffer gap 150 and can be moved in the thermal buffer gap 150 along the first direction 101. When it is necessary to cool down the carrier plate 120 and the wafer, the thermal insulation sheet 141 can be controlled to move upward and close to the carrier plate 120. Since the air content between the thermal insulation sheet 141 and the carrier plate 120 is reduced, the thermal resistance is reduced, so that the heat transfer rate between the carrier plate 120 and the cooling component 130 is increased, and more heat can be transferred from the carrier plate 120 to the cooling component 130; when it is necessary to heat up the carrier plate 120 and the wafer, the thermal insulation sheet 141 can be controlled to move downward and close to the cooling component 130. Since the air content between the thermal insulation sheet 141 and the carrier plate 120 is increased, the thermal resistance is increased, the heat transfer rate between the carrier plate 120 and the cooling component 130 is reduced, and only a small amount of heat is transferred from the carrier plate 120 to the cooling component 130. By adjusting the heat transfer rate between the carrier plate 120 and the cooling component 130 , on the one hand, the temperature adjustment accuracy of the carrier plate 120 can be improved, and on the other hand, the heating efficiency of the heating element 121 can be improved and the energy consumption of the heating element 121 can be reduced.

[0052] The above embodiments of the present application focus on describing the differences between the various embodiments. As long as the different technical features between the various embodiments are not contradictory, they can be combined to form more specific embodiments. Considering the simplicity of the text, they will not be repeated here.

[0053] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. An electrostatic chuck, characterized in that: It comprises a base (110), a carrier plate (120), a cooling component (130) and a temperature adjustment component (140); The carrying plate (120) is covered on the open end of the base (110) and forms a containing cavity with the base (110); a heating element (121) is provided inside the carrying plate (120); The cooling component (130) is arranged in the accommodating cavity, and a thermal buffer gap (150) is provided between the carrier plate (120) and the cooling component (130) along a first direction (101); the temperature adjustment component (140) comprises a thermal insulation sheet (141), and the thermal insulation sheet (141) is arranged in the thermal buffer gap (150) and can move in the thermal buffer gap (150) along the first direction (101) to adjust the heat transfer rate between the carrier plate (120) and the cooling component (130); Wherein, the first direction (101) is perpendicular to the disk surface of the supporting disk (120).

2. The electrostatic chuck according to claim 1, characterized in that: There are multiple thermal insulation sheets (141), and projections of the multiple thermal insulation sheets (141) along the first direction (101) cover at least a portion of the carrier plate (120), and the multiple thermal insulation sheets (141) respectively cover different local areas.

3. The electrostatic chuck according to claim 2, characterized in that: The heating element (121) is an annular structure and is extended along the circumference of the carrier plate (120). A plurality of the heat insulation sheets (141) are arranged in the heat buffer gap (150) at intervals along the circumference of the carrier plate (120).

4. The electrostatic chuck according to claim 3, characterized in that: The plurality of heat-insulating sheets (141) are arranged at intervals along the circumference of the carrier plate (120), and respectively form a plurality of mutually nested annular adjustment areas (142); along the first direction (101), the projections of the plurality of annular adjustment areas (142) jointly cover the carrier plate (120).

5. The electrostatic chuck according to claim 1, characterized in that: The temperature adjustment component (140) further comprises a driving mechanism, wherein the driving mechanism is connected to the heat insulation sheet (141) so as to drive the heat insulation sheet (141) to move in the heat buffer gap (150) along the first direction (101).

6. The electrostatic chuck according to claim 5, characterized in that: The driving mechanism comprises a threaded shaft (143); a threaded hole (111) is provided at the bottom of the base (110); one end of the threaded shaft (143) passes through the threaded hole (111) and extends into the thermal buffer gap (150), and is connected to the thermal insulation sheet (141); the threaded shaft (143) is threadedly matched with the threaded hole (111) to drive the thermal insulation sheet (141) to move along the first direction (101) in the thermal buffer gap (150).

7. The electrostatic chuck according to claim 6, characterized in that: The cooling component (130) comprises a cooling plate (131) and a cooling pipeline (132); the cooling plate (131) is arranged in the accommodating cavity; the cooling plate (131) comprises a first end surface and a second end surface opposite to each other along the first direction (101); a thermal buffer gap (150) is provided between the first end surface and the supporting plate (120); and the second end surface is close to the bottom of the base (110); The cooling pipeline (132) is arranged on the base (110) and the cooling plate (131), and an end of the cooling pipeline (132) is used to communicate with a cooling fluid source.

8. The electrostatic chuck according to claim 7, characterized in that: The threaded shaft (143) comprises a driving shaft (1431) and a driven shaft (1432); the driving shaft (1431) is threadably matched with the threaded hole (111); The cooling plate (131) is provided with a first avoidance hole (1311), the first end of the driven shaft (1432) is connected to the end of the threaded shaft (143), and the second end of the driven shaft (1432) passes through the first avoidance hole (1311) and extends into the thermal buffer gap (150), and is connected to the thermal insulation plate (141).

9. The electrostatic chuck according to claim 8, characterized in that: The temperature adjustment component (140) further comprises a limit block (144), wherein the limit block (144) is disposed in the threaded hole (111) and is in position-limiting cooperation with an end portion of the driving shaft (1431) facing away from the driven shaft (1432); The limit block (144) is provided with a through hole (1441), and the through hole (1441) is used for allowing a driving source of the driving mechanism to pass through, and the driving source is used to drive the driving shaft (1431) to rotate relative to the threaded hole (111).

10. The electrostatic chuck according to claim 7, characterized in that: The supporting plate (120) includes a plate body (122) and a metal connecting part (123), wherein the plate body (122) is covered on the open end of the base (110) and forms the accommodating cavity together with the base (110), the metal connecting part (123) is arranged in the accommodating cavity, at least a part of the metal connecting part (123) is welded and fixed to the surface of the plate body (122) close to the accommodating cavity, the thermal buffer gap (150) is provided between the first end surface of the cooling plate (131) and the metal connecting part (123), and the base (110) is connected to the metal connecting part (123) via fasteners.

11. The electrostatic chuck according to claim 10, characterized in that The electrostatic chuck further comprises a heat-insulating ring (160), wherein the heat-insulating ring (160) is arranged at an edge region of the thermal buffer gap (150), and two opposite end surfaces of the heat-insulating ring (160) are respectively in contact with the cooling disk (131) and the metal connecting portion (123).

12. The electrostatic chuck according to claim 11, characterized in that The electrostatic chuck also includes an elastic member (170), wherein the elastic member (170) is disposed between the second end surface of the cooling disk (131) and the base (110), and the elastic member (170) is used to apply an elastic pre-tightening force to the cooling disk (131) so that the cooling disk (131) is pressed against the thermal insulation ring (160).

13. The electrostatic chuck according to claim 10, characterized in that: An annular platform (112) is extended from the inner wall of the base (110) close to the opening end, and the annular platform (112) is arranged opposite to the edge of the metal connecting part (123). A sealing structure (180) is provided between the annular platform (112) and the metal connecting part (123), and the sealing structure (180) is respectively connected to the annular platform (112) and the metal connecting part (123).

14. The electrostatic chuck according to claim 10, characterized in that The metal connection part (123) is provided with a fluid channel (1231), and the fluid channel (1231) is used to communicate with a fluid heat-conducting medium source. The end surface of the disk body (122) used for adsorbing wafers is provided with a flow hole (1221), and the flow hole (1221) is connected with the fluid channel (1231).

15. A semiconductor process equipment, characterized in that: It comprises a process chamber and the electrostatic chuck according to any one of claims 1 to 14, wherein the electrostatic chuck is arranged in the process chamber.

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