Workpiece table and semiconductor process equipment

Abstract

The invention discloses a workpiece table and semiconductor process equipment, and the workpiece table comprises a substrate which is provided with a first surface and a second surface which are opposite, and the first surface is used for bearing a to-be-processed workpiece; the substrate comprises a plurality of parts which are spliced pairwise, and the heat conductivity coefficients of the parts are different. Wherein for any two adjacent components in the multiple components, the curved surface shapes of the splicing surfaces of the two components are attached to a preset heat transfer optimization curved surface, the preset heat transfer optimization curved surface is used for representing that when the temperature difference between any two positions on the first surface is within a preset tolerance range, the temperature difference between any two positions on the second surface is within the preset tolerance range. And the splicing surface is in a curved surface shape. According to the scheme, the temperature uniformity of the surface of the substrate can be optimized, the to-be-machined workpiece borne by the workpiece table is heated or cooled more evenly, the equipment complexity is low, and the implementation cost is low.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor processing, and in particular to a workpiece table and semiconductor process equipment. Background Art

[0002] The semiconductor equipment industry is a supporting industry in the semiconductor industry chain, providing related machinery and equipment for the manufacturing and packaging and testing of integrated circuits. Over the past few decades, the integrated circuit industry has developed rapidly, the product processing area has shrunk by multiples, the process complexity has increased year by year, and the requirements for the processing accuracy and stability of manufacturing equipment have continued to increase. Semiconductor product manufacturing is highly dependent on equipment. As the precision requirements for semiconductor products become higher and higher, the temperature uniformity requirements for samples involved in its equipment also increase accordingly. The substrate temperature needs to be balanced to ensure the uniformity of processing, and the energy generated by radio frequency, microwaves, etc. is transferred to the substrate, which will cause the base (also called substrate) temperature to be high in the middle and low on both sides, thereby reducing the processing uniformity.

[0003] In existing semiconductor equipment, the only way to deal with the degradation of process quality caused by uneven substrate temperature due to RF, microwave and other energy is to accept it. Only a few semiconductor devices are equipped with thermal compensation devices to alleviate the uneven substrate surface temperature caused by RF, microwave and other energy transfer methods through active heating. However, the method of thermal compensation of the substrate by heating wires and other similar devices used in such equipment is often costly, complex in structure and high in failure rate. At present, most solutions are to improve the uniformity of the heating field by modifying the mechanical structure and heating method of semiconductor equipment, thereby ensuring uniform heating of the sample. The disadvantages are that the modification plan is complicated, the manufacturing is difficult, and the cost of later testing is high. Summary of the invention

[0004] The technical problem solved by the present invention is to provide an improved workpiece stage capable of achieving substrate temperature balance with lower equipment complexity and cost.

[0005] In order to solve the above technical problems, an embodiment of the present invention provides a workpiece table, including: a substrate, having a first surface and a second surface relative to each other, the first surface is used to support a workpiece to be processed; the substrate includes: a plurality of components spliced ​​in pairs, and the thermal conductivity coefficients of the plurality of components are different; wherein, for any two adjacent components among the plurality of components, the curved surface shape of the splicing surface of the two components fits a preset heat transfer optimization surface, and the preset heat transfer optimization surface is used to characterize the curved surface shape of the splicing surface when the temperature difference between any two positions on the first surface falls within a preset tolerance range.

[0006] Optionally, the multiple components form a plurality of joint surfaces, the number of the preset heat transfer optimization curved surfaces is multiple, and the multiple preset heat transfer optimization curved surfaces correspond one-to-one to the multiple joint surfaces.

[0007] Optionally, the preset heat transfer optimization surface is obtained by fitting according to the heat transfer equation of the two components under a preset total heating power.

[0008] Optionally, the first surface and the second surface are circular. In the cross-section of the substrate along the radial direction of the circle, for any two adjacent components among the multiple components, the curvature change of the splicing seam between the two components satisfies a preset heat transfer optimization curve, where the preset heat transfer optimization surface includes multiple such preset heat transfer optimization curves.

[0009] Optionally, the preset heat transfer optimization curve is obtained by fitting according to the heat transfer equation of the two components under a preset total heating power.

[0010] Optionally, for any two adjacent components among the multiple components, the difference in the thermal conductivity of the two components is greater than a preset threshold.

[0011] Optionally, the multiple components include a first component and a second component. The first surface includes a first region and a second region. The first component includes a first concave portion protruding towards the first region and a first convex portion protruding in a direction away from the second region. The second component includes a second convex portion for filling the first concave portion and a second concave portion for avoiding the first convex portion. The first concave portion and the second convex portion, and the first convex portion and the second concave portion cooperate to make the temperature difference between the first region and the second region fall within the preset tolerance range.

[0012] Optionally, the multiple components include a first component and a second component, and both the first component and the second component are made of metal materials.

[0013] Optionally, the first surface and the second surface are formed by different components.

[0014] Optionally, the multiple components include: a first component for forming the first surface, the first component being made of an inorganic non-metallic material; a second component for forming the second surface, the first component and the second component being partially spliced, the second component being made of an inorganic non-metallic material; and a third component located between the non-spliced parts of the first component and the second component, the third component being made of a metal material.

[0015] Optionally, the third component is closer to the edge of the substrate than to the center of the substrate.

[0016] Optionally, the fixed connection method between adjacent components is at least selected from: friction welding, tight fit, and seamless welding.

[0017] To solve the above technical problems, an embodiment of the present invention further provides a semiconductor processing apparatus, which is characterized by comprising: a process chamber; the above-mentioned workpiece table, which is accommodated in the process chamber; a heat source, which is arranged in the process chamber and above the substrate.

[0018] Optionally, the preset heat transfer optimization surface is related to the processing technology of the semiconductor processing apparatus.

[0019] Optionally, the plurality of components include a first component, and the first component is used to form the first surface, and the material of the first component is determined according to the processing technology of the semiconductor processing apparatus.

[0020] Compared with the prior art, the technical solution of the embodiment of the present invention has the following beneficial effects:

[0021] An embodiment of the present invention provides a workpiece table, which includes: a substrate having opposite first and second surfaces, and the first surface is used to carry a workpiece to be processed; the substrate includes: a plurality of components spliced pairwise, and the thermal conductivities of the plurality of components are different; wherein, for any two adjacent components among the plurality of components, the curved surface shape of the splicing surface of the two components fits a preset heat transfer optimization surface, and the preset heat transfer optimization surface is used to characterize: when the temperature difference between any two positions on the first surface falls within a preset tolerance range, the curved surface shape of the splicing surface.

[0022] Adopting this implementation scheme, by splicing a plurality of components with different thermal conductivities pairwise to form a substrate, and making the curved surface shape of the splicing surface of any two adjacent components fit the preset heat transfer optimization surface, the heat transfer of the substrate can be made more uniform, and further the workpiece to be processed carried on the substrate can be heated more uniformly. Thus, the uniformity of the temperature on the surface of the substrate can be optimized, and the workpiece to be processed carried by the workpiece table can be heated or cooled more evenly. Further, the optimized substrate material uniform heat diffusion scheme provided in this embodiment can better reduce the temperature deviation at each part of the surface of the substrate (for example, the first surface) during heat diffusion, and reduce the lattice damage and other defects caused by the temperature difference on the surface of the workpiece to be processed (for example, the substrate). Further, in the substrate of this implementation scheme, uniform heat transfer can be achieved by adjusting the shape of the splicing surface of each component with different thermal conductivities, without additionally installing a heating compensation mechanism, nor changing the original functional structure of the workpiece table. Directly installing the substrate provided in this implementation scheme can ensure the temperature balance of the substrate, with a simple structure and low production cost.

[0023] Furthermore, the splicing surface can be flexibly changed to the required shape according to different preset heat transfer optimization surfaces, and the prepared substrate is not limited by size and can be compatible with most semiconductor processing apparatuses.

[0024] Furthermore, in this implementation, the shape of the splicing surface between any two adjacent components can be adjusted through preset parameter design to achieve the desired substrate surface temperature distribution, thereby realizing the temperature field regulation within the workpiece to be processed.

[0025] Furthermore, this implementation can be applied to the application scenario of a heating-type workpiece stage, and can also be applied to a heat dissipation-type workpiece stage.

[0026] Furthermore, an embodiment of the present invention also provides a semiconductor process equipment, including: a process chamber; the above-mentioned workpiece stage, which is accommodated in the process chamber; a heat source, which is arranged in the process chamber and above the substrate.

[0027] By adopting this implementation, according to the specific application scenario (for example, the processing technology of semiconductor process equipment, the material of the workpiece to be processed that needs to be heated, etc.), the heat transfer equations of various materials with different thermal conductivities are calculated, and a preset heat transfer optimization curve (or preset heat transfer optimization surface) is optimized. According to the preset heat transfer optimization curve, the curved surface shape of the splicing surface is determined, and each part component is manufactured according to the curved surface shape and assembled together to form a substrate. After the substrate receives the heat provided by the heat source, the temperature distribution on the substrate surface is more uniform and consistent. Furthermore, the heating or heat dissipation of the workpiece to be processed placed on the substrate of the workpiece stage will also be more uniform.

[0028] Furthermore, this implementation adopts a pure passive heat uniformity scheme. According to the requirements of specific application scenarios such as the processing technology of semiconductor process equipment, the heat distribution curve is determined, and the uneven heat distribution areas are compensated in advance with different materials through calculation methods, without setting additional heating modules or heat compensation modules to actively adjust the temperature. Thus, through the passive heat dissipation structure, uniform heat diffusion is achieved in a low-cost and low-complexity manner. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a schematic diagram of a workpiece stage according to an embodiment of the present invention;

[0030] Figure 2 is Figure 1 a perspective view of the workpiece stage shown;

[0031] Figure 3 is Figure 1 a cross-sectional view along the A-A direction;

[0032] Figure 4 is Figure 1 an exploded view of the workpiece stage shown;

[0033] Figure 5 is Figure 4 a sectional view along the B-B direction;

[0034] Figure 6It is the temperature curve graph for simulating two materials in the first typical application scenario of the embodiment of the present invention;

[0035] Figure 7 is Figure 6 The schematic diagram of the simulation model for simulating two materials in the shown application scenario;

[0036] Figure 8 It is the temperature curve graph for simulating three materials in the second typical application scenario of the embodiment of the present invention;

[0037] Figure 9 is Figure 8 The schematic diagram of the simulation model for simulating three materials in the shown application scenario;

[0038] Figure 10 It is the schematic diagram of a semiconductor process equipment according to an embodiment of the present invention. Detailed implementation manners

[0039] As described in the background art, existing semiconductor equipment often improves the uniformity of the heating thermal field by modifying the mechanical structure and heating method of the semiconductor equipment. The modification scheme is complex, the manufacturing difficulty is high, and the later test investment cost is high.

[0040] Specifically, most manufacturers concentrate their scientific research efforts on a few product lines. In the early R & D stage, due to the use of wafer substrates made of different materials, it is unrealistic to change the conventional equipment heating method, and the original heating system of the equipment often cannot ensure the uniform heating of the substrate. Traditional heating type workpiece tables or other heat dissipation type workpiece tables are coupled with other energy sources such as plasma during the process, resulting in non-uniform heat flux density on the substrate surface, thereby affecting process consistency. Although the temperature uniformity of the substrate surface can be improved by technical means such as zoning control of the heating type workpiece table, it brings complex heater and workpiece table designs and affects process robustness.

[0041] To solve the above technical problems, an embodiment of the present invention provides a workpiece table, including: a substrate having opposite first and second surfaces, the first surface being used to carry a workpiece to be processed; the substrate includes: a plurality of components spliced pairwise, and the plurality of components have different thermal conductivities; wherein, for any two adjacent components among the plurality of components, the curved surface shape of the splicing surface of the two components fits a preset heat transfer optimization curved surface, and the preset heat transfer optimization curved surface is used to characterize the curved surface shape of the splicing surface when the temperature difference between any two positions on the first surface falls within a preset tolerance range.

[0042] Thus, by splicing together a plurality of components with different thermal conductivities in pairs to form a substrate, and making the curved surface shape of the joint surface of any two adjacent components fit the preset heat transfer optimization curved surface, the heat transfer of the substrate can be made more uniform, and the workpiece to be processed carried on the substrate can be heated more evenly. Thus, the uniformity of the temperature of the substrate surface can be optimized, so that the workpiece to be processed carried by the worktable is heated or dissipated more evenly. Further, the uniform heat diffusion scheme of the optimized substrate material provided in this embodiment can better reduce the temperature deviation of various parts of the substrate surface (for example, the first surface) during heat diffusion, and reduce the lattice damage and other defects caused by the temperature difference on the surface of the workpiece to be processed (for example, the substrate). Further, the substrate in this embodiment can achieve uniform heat transfer by adjusting the joint surface shape of each component with different thermal conductivities, without the need to add an additional heating compensation mechanism, and without changing the original functional structure of the worktable. The direct installation of the substrate provided by this embodiment can ensure that the substrate temperature is balanced, the structure is simple, and the production cost is low.

[0043] In order to make the above-mentioned objects, features and beneficial effects of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0044] Figure 1 is a schematic diagram of a workpiece platform 101 according to an embodiment of the present invention, Figure 2 yes Figure 1 A perspective view of the workpiece stage 101 is shown, Figure 3 yes Figure 1 Cross-sectional view along AA direction, Figure 4 yes Figure 1 An exploded view of the workpiece stage 101 is shown; Figure 5 yes Figure 3 Schematic diagram after cutting along the BB direction.

[0045] Combination Figures 1 to 5 The workpiece stage 101 may include a substrate 1. The substrate 1 has a first surface 11 and a second surface 12 opposite to each other. For ease of description, the direction from the first surface 11 to the second surface 12 is recorded as the height direction of the substrate 1. The first surface 11 is used to carry a workpiece to be processed.

[0046] Specifically, the workpiece stage 101 may include a heating workpiece stage or other heat dissipation workpiece stage. The embodiment of the present invention mainly takes the heating workpiece stage as an example for illustrative explanation.

[0047] Furthermore, the workpiece stage 101 may also include a motion mechanism (not shown) for controlling the movement of the substrate 1. For example, the motion mechanism is used to control the movement of the substrate 1 to adjust the geometric center of the first surface 11 and the heat source 103 (such as Figure 10) relative position. Thus, when the projection of the heat source 103 on the first surface 11 coincides with the geometric center of the first surface 11, the heat transfer effect between the heat source 103 and the workpiece stage 101 can be optimized. For another example, the substrate 1 is controlled to move by a motion mechanism to transport the workpiece to be processed carried on the substrate 1 to a designated position (such as Figure 10 the process chamber 102 shown).

[0048] Furthermore, the workpiece to be processed can be, for example, a substrate. The substrate can be, for example, a bare wafer (i.e., a light sheet wafer), or can also be a wafer that has been processed by a previous process and formed with one or more device structures.

[0049] Furthermore, the substrate 1 includes: a plurality of components 2 spliced in pairs, and the thermal conductivities of the plurality of components 2 are different.

[0050] In Figures 1 to 5 the embodiment shown, the number of the plurality of components 2 can be, for example, two.

[0051] In a variant, the number of the plurality of components 2 can be three or more, and in this scenario, the thermal conductivities of the plurality of components 2 are different from each other.

[0052] Furthermore, for any two adjacent components 2 among the plurality of components 2, the curved surface shape of the splicing surface 3 of the two components 2 fits the preset heat transfer optimization surface 4.

[0053] It should be noted that Figure 3 the splicing surface 3 shown in does not completely coincide with the preset heat transfer optimization surface 4, which is to more clearly show the fitting relationship between the curved surface shape of the splicing surface 3 and the curved surface shape of the preset heat transfer optimization surface 4. In practical applications, the splicing surface 3 and the preset heat transfer optimization surface 4 are substantially coincident, that is, the splicing surface 3 is processed according to the preset heat transfer optimization surface 4 to make the heat transfer between the components more uniform and the temperature distribution on the first surface 11 more consistent.

[0054] In some embodiments, the curved surface shape of the splicing surface 3 can include a plane and a local plane.

[0055] Furthermore, the preset heat transfer optimization surface 4 is used to characterize the curved surface shape of the splicing surface 3 when the temperature difference between any two positions on the first surface 11 falls within a preset tolerance range.

[0056] Specifically, the preset tolerance range can be, for example, 0.1 - 0.4 °C. That is to say, the temperature from the geometric center to the edge of the first surface 11 is basically kept consistent (or fluctuates within a very small temperature range). Thus, the substrate placed on the first surface 11 can be heated more evenly.

[0057] In a specific implementation, a plurality of splicing surfaces 3 may be formed between a plurality of components 2.

[0058] Specifically, n components 2 may form m splicing surfaces 3, where n≥2 and m≤n.

[0059] For example, in an embodiment where the substrate 1 is composed of two components 2, one splicing surface 3 may be formed between the two components 2.

[0060] For another example, in an embodiment where the substrate 1 is composed of three components 2, two or three splicing surfaces 3 may be formed between the three components 2.

[0061] Furthermore, the number of preset heat transfer optimization surfaces 4 is also a plurality, and the plurality of preset heat transfer optimization surfaces 4 and the plurality of splicing surfaces 3 correspond one by one. The one-to-one correspondence means that among the m preset heat transfer optimization surfaces 4, the surface shape of the i-th preset heat transfer optimization surface 4 is consistent with the surface shape of the i-th splicing surface 3 among the m splicing surfaces 3, where 1≤i≤m.

[0062] That is to say, for the splicing surface 3 between any two adjacent components 2, the surface shape of the splicing surface 3 is determined according to the surface shape of the corresponding preset heat transfer optimization surface 4. By analogy, the surface shapes of all splicing surfaces 3 are determined and the components 2 are assembled to obtain the substrate 1.

[0063] In a specific implementation, for any two adjacent components 2 among the plurality of components 2, the preset heat transfer optimization surface 4 is obtained by fitting according to the heat transfer equation of these two components 2 under a preset total heating power.

[0064] Furthermore, the fitting method may be, for example, three-dimensional fitting. The heat transfer equation may be, for example, an equation that describes the law of heat transfer between two components 2. According to the heat transfer equation, the shape of the splicing surface 3 between the two components 2 is adjusted so that the temperature difference between any two positions on the first surface 11 of the substrate 1 falls within a preset tolerance range.

[0065] Continue to refer to Figures 1 to 5 , the first surface 11 and the second surface 12 are circular. In the cross-section of the substrate 1 along the radial direction of the circle, for any two adjacent components 2 among the plurality of components 2, the curvature change of the splicing seam 5 between the two components 2 satisfies a preset heat transfer optimization curve 6, where the preset heat transfer optimization surface 4 includes a plurality of the preset heat transfer optimization curves 6.

[0066] In some embodiments, the circular first surface 11 is used to carry a circular substrate. Further, the edge of the first surface 11 may protrude away from the second surface 12 to form an annular structure 13, and the substrate may be placed in the cavity surrounded by the annular structure 13. This helps to prevent the substrate from accidentally falling off the first surface 11.

[0067] Specifically, the shape of the substrate 1 may be a symmetric structure (such as Figure 1 the cylinder shown), including a first surface 11 facing the workpiece to be processed and a second surface 12 facing away from the workpiece to be processed. Since the substrate 1 is a symmetric structure at this time, two-dimensional fitting can be performed to obtain a preset heat transfer optimization curve 6. Then, the preset heat transfer optimization curve 6 is rotated around the axis (i.e., the axis of symmetry of the symmetric structure) for one week to form a preset heat transfer optimization surface 4. In other words, the preset heat transfer optimization surface 4 is formed by multiple preset heat transfer optimization curves 6 radially extending outward from the axis. Among them, the axis is perpendicular to the first surface 11 and passes through the center of the first surface 11.

[0068] In some embodiments, iterative calculations can also be performed through simulation software, and the preset heat transfer optimization curve 6 can be adjusted according to the simulation data effect to obtain an optimal solution for a specific process. Further, the simulation software can automatically adjust the preset heat transfer optimization curve 6 according to the data results, and then multiple preset heat transfer optimization curves 6 form a preset heat transfer optimization surface 4.

[0069] In Figure 6 and Figure 7 the application scenario shown, the substrate 1 is composed of two components 2, and the two components 2 are made of copper (Cu) and molybdenum (Mo) respectively. Further, according to the relevant parameters of the heat source 103 (such as the preset total heating power) and the thermal conductivity coefficients of copper and molybdenum respectively, the heat transfer equation is calculated. Then, according to the heat transfer equation, the preset heat transfer optimization curve 6 is obtained. Further, the two components 2 are spliced together to form the substrate 1 by means of splicing or seamless welding.

[0070] In some embodiments, as Figure 7 shown, the structure may be a quarter-sectional structure of the substrate 1, that is, Figure 2 the sectional structure along the A-A direction. Figure 7 In, the ordinate is the dimension in the height direction of the substrate 1 (unit: centimeter cm), and the abscissa is the dimension perpendicular to the height direction of the substrate 1 (for example, the length in the radial direction of the substrate 1, unit: centimeter cm). By adjusting Figure 7 the curvature change of the splicing seam between the first component 21 and the second component 22 in, so that Figure 6 the change of temperature with distance in the curve C3 in is basically kept constant. At this time, Figure 7The splicing seam 5 shown is the preset heat transfer optimization curve 6 obtained by fitting. Then, Figure 7 the shown cross-section is rotated one week around the axis a1, and the substrate 1 can be obtained. Correspondingly, Figure 7 the splicing seam 5 shown is rotated one week around the axis a1 to form the splicing surface 3. At this time, the splicing surface 3 basically coincides with the preset heat transfer optimization surface 4, so that the heat transfer inside the substrate 1 is more uniform, and the temperature distribution on the first surface 11 is also more uniform and consistent.

[0071] In a variant, the first surface 11 and the second surface 12 can also be set to various shapes according to specific application scenarios and usage requirements, such as square, rectangular and other shapes. By making the shape of the splicing surface 3 between any two adjacent components 2 in the plurality of components 2 basically coincide with the preset heat transfer optimization surface 4 obtained by fitting, the temperature distribution on the first surface 11 can be made uniform and consistent.

[0072] Furthermore, for any two adjacent components 2 in the plurality of components 2, the difference in the thermal conductivity of the two components 2 is greater than a preset threshold. Thus, a significant temperature compensation is achieved at the required position through a large difference in thermal conductivity.

[0073] Specifically, the preset threshold can be, for example, 100 - 260 W / (m·K).

[0074] Furthermore, in combination with Figures 2 to 5 , the plurality of components 2 includes a first component 21 and a second component 22, the first surface 11 includes a first region E1 and a second region E2, the first component 21 includes a first concave portion 211 protruding towards the first region E1 and a first convex portion 212 protruding in a direction away from the second region E2, the second component 22 includes a second convex portion 221 for filling the first concave portion 211 and a second concave portion 222 for avoiding the first convex portion 212, and the first concave portion 211 and the second convex portion 221, the first convex portion 212 and the second concave portion 222 cooperate to make the temperature difference between the first region E1 and the second region E2 fall within the preset tolerance range. Thus, through the special shape design of different materials with a large difference in thermal conductivity, the places with uneven heat distribution can be compensated in advance.

[0075] In some embodiments, the surface of the first component 21 facing away from the second component 22 is adapted to form the first surface 11. Further, the first component 21 can be made of a material with a small thermal conductivity, and the second component 22 can be made of a material with a large thermal conductivity, and the difference in their thermal conductivities is greater than the preset threshold.

[0076] In this scenario, in the area where the temperature of the first surface 11 is relatively low, the temperature of this area can be appropriately increased by adding materials with a large thermal conductivity and correspondingly reducing materials with a small thermal conductivity, so that the temperature difference between this area and other high-temperature areas falls within a preset tolerance range. For example, when the temperature of the first area E1 is relatively low, the first component 21 can be made to bulge towards the first area E1 to form a first recess 211, and at the same time, a second protrusion 221 for filling the first recess 211 is formed on the second component 22, so as to thermally compensate for the temperature difference of the first area E1 by increasing the proportion of the second component 22 near the first surface 11.

[0077] In the area where the temperature of the first surface 11 is relatively high, a convex first protrusion 212 can be formed by adding materials with a small thermal conductivity, and correspondingly reducing materials with a large thermal conductivity, so that the temperature of this area is appropriately decreased to make the temperature difference between this area and other areas fall within a preset tolerance range. For example, when the temperature of the second area E2 is relatively high, the first component 21 can be made to bulge in a direction away from the second area E2 to form a first protrusion 212, and at the same time, a second recess 222 for avoiding the first protrusion 212 is formed on the second component 22, so as to thermally compensate for the temperature difference of the second area E2 by reducing the proportion of the second component 22 in the entire substrate 1.

[0078] In some embodiments, according to the specific materials of the first component and the second component selected, more protrusions and corresponding recesses can also be provided on the first component 21 and the second component 22 to thermally compensate for different areas.

[0079] In some embodiments, both the first component 21 and the second component 22 can be made of metal materials. Metal materials usually have a relatively high thermal conductivity, so that the stable state of heat transfer can be reached faster, saving operation time.

[0080] Furthermore, the first surface 11 and the second surface 12 are formed by different components 2.

[0081] In a typical application scenario, due to special requirements for the material of the first surface 11 in a specific process, the first component 21 can be made of molybdenum, and the first surface 11 is formed by the first component 21. Further, considering the problem of uneven temperature distribution on the first surface 11 of the substrate 1 made of a single molybdenum material, in this implementation scheme, a second component 22 made of copper is introduced for temperature compensation, and the second surface 12 is formed by the second component 22. The preset optimized heat transfer surface when these two materials are joined together is obtained through simulation experiments, and the shape of the joint surface 3 between them is obtained.

[0082] In some embodiments, referring to Figure 9, the plurality of components 2 includes: a first component 21 for forming the first surface 11, the first component 21 being made of an inorganic non-metallic material; a second component 22 for forming the second surface 12, the first component 21 and the second component 22 being partially spliced, the second component 22 being made of an inorganic non-metallic material; and a third component 23 located between the non-spliced parts of the first component 21 and the second component 22, the third component 23 being made of a metallic material.

[0083] In a typical application scenario, due to special requirements for the first surface 11 in a specific process, such as requiring the second surface 12 to be non-conductive to the first surface 11, the substrate 1 is preferably a dielectric substrate. At this time, the first component 21 can be made of calcium titanate (CaTiO3), and the first surface 11 is formed by the first component 21. Further, considering the problem of uneven temperature on the first surface 11 of the substrate 1 made of a single calcium titanate material, in this implementation, a second component 22 made of silicon dioxide (SiO2) is introduced for temperature compensation, and the second surface 12 is formed by the second component 22. Further, it is found in the simulation process that for the dielectric substrate formed by splicing these two materials, the temperature change in most areas of the first surface 11 is relatively balanced, but the temperature change in individual areas (such as the edge area) is still large, and it cannot be solved by adjusting the concave / convex ratio of these two materials in the edge area. Therefore, a third component 23 can also be introduced. The third component 23 can be made of copper, and the third component 23 is disposed between the non-spliced parts of the first component 21 and the second component 22 (such as disposed in the aforementioned edge area), and can respectively perform mutual heat transfer with the first component 21 and the second component 22.

[0084] Further, through simulation experiments, when these three materials are spliced together, the preset heat transfer optimization surface 4 between each pair is obtained, and the shape of the splicing surface 3 between each pair is obtained. Thus, through simulation experiments, the preset heat transfer optimization surfaces 6 between the first component 21 and the second component 22, the second component 22 and the third component 23, and the third component 23 and the first component 21 are respectively obtained, and then the shape of the splicing surface 3 between each component 2 is made to basically coincide with the preset heat transfer optimization surface 4, so that the temperature difference between any two positions on the first surface 11 falls within the preset tolerance range, and the temperature distribution is more uniform and consistent.

[0085] Further, the third component 23 is closer to the edge of the substrate 1 than to the center of the substrate 1. Thus, by adding the third component 23, a better heat equalization effect can be obtained, and it can effectively avoid the uneven distribution of the temperature of the substrate 1 with the characteristic of "high in the center - low at the edge".

[0086] Further, the fixed connection method between adjacent components 2 is at least selected from: friction welding, tight fitting, and seamless welding. Thus, other substances such as solder introduced by other welding methods can be avoided from affecting the uniformity of heat transfer.

[0087] To further illustrate the beneficial effect that the embodiments of the present invention can produce a uniform temperature distribution on the first surface 11 of the substrate 1, the inventors of the present application took the application scenarios with two components 2 of the cylindrical substrate 1 and the application scenarios with three components 2 as examples to conduct simulation experiments. In each simulation experiment, the shapes of the first surface 11 and the second surface 12 were both set to circles with a diameter of 2 centimeters (cm), and the same heat source 103 (200 °C) and the same heat convection parameters (750 W / (m 2 ·K)) were adopted. Further, in each simulation experiment, the temperature change of the first surface 11 was characterized by the temperature change on any radius on the first surface 11.

[0088] In each simulation experiment, first, the parameters of the fixed heat source 103 (such as Figure 10 ) (such as the preset total heating power, heat convection parameters, etc.) were input into the simulation software. The shape of the initial splicing surface 3 was set according to experience, and the shape of the local area was adjusted according to the simulation results. For example, if a high or low thermal conductivity material is required in this area, the shape of the splicing surface 3 of the two materials in this area was adjusted accordingly to make it concave or convex.

[0089] In Simulation Experiment 1, simulations were respectively conducted on the substrates 1 made of pure copper, pure molybdenum, and the substrate 1 formed by copper - molybdenum splicing, and the Figure 6 three temperature curves C1 to C3 as shown were obtained. Figure 6 In, the abscissa is the distance (unit: centimeter cm) from the measured point to the geometric center of the first surface 11 (for example, Figure 7 the axis a1 in), and the ordinate is the temperature (unit: degree Celsius °C). Figure 6 The curves C1 to C3 shown are the curves of the temperature change with distance on the first surface 11 of the substrates 1 formed by different materials.

[0090] Among them, curve C1 represents the temperature change on the first surface 11 of the substrate 1 made of pure copper. Referring to Figure 6 it can be seen that the farther away from the axis a1 of the first surface 11 (that is, the geometric center of the first surface 11), the lower the temperature. And the closer to the edge of the first surface 11, the faster the temperature drops. The difference between the temperature at about 1.8 cm away from the axis a1 and the temperature at the axis a1 has exceeded the preset tolerance range. It can be seen that using a substrate 1 made of pure copper will cause uneven heating of the workpiece to be processed (for example, a substrate), affecting the process consistency.

[0091] Curve C2 represents the temperature change on the first surface 11 of the substrate 1 made of pure molybdenum. Referring toFigure 6 It can be seen that the farther away from the axis a1 of the first surface 11 (i.e., the geometric center of the first surface 11), the lower the temperature. Moreover, the closer to the edge of the first surface 11, the faster the temperature drops. The difference between the temperature at a distance of about 1.5 cm from the axis a1 and the temperature at the axis a1 has exceeded the preset tolerance range. It can be seen that using a substrate 1 made of pure molybdenum will cause uneven heating of the workpiece to be processed (such as a substrate), affecting process consistency.

[0092] Curve C3 represents the temperature change on the first surface 11 of the substrate 1 formed by using molybdenum and copper as the first component 21 and the second component 22 respectively and joined together according to the preset heat transfer optimization surface 4 (for example, obtained by rotating the preset heat transfer optimization curve 6 in Figure 7 around the axis a1 for one circle). Refer to Figure 6 It can be seen that as the distance from the axis a1 of the first surface 11 (i.e., the geometric center of the first surface 11) increases, the temperature basically remains unchanged. In other words, the temperature distribution on the first surface 11 is basically uniform and consistent. At this time, the joining method of the first component 21 and the second component 22 can be as shown in Figure 7 .

[0093] In the second simulation experiment, simulations were respectively carried out on the substrate 1 made of pure calcium titanate, pure silicon dioxide, and the substrate 1 formed by the combination of calcium titanate - silicon dioxide - copper, and three temperature curves C4 to C6 as shown in Figure 8 were obtained. Figure 8 In Figure 9 , the abscissa is the distance (unit: centimeter cm) from the measured point to the geometric center of the first surface 11 (such as the axis a2 in Figure 8 ), and the ordinate is the temperature (unit: degree Celsius °C). The curves C1 to C3 shown in

[0094] are the temperature change curves with distance on the first surface 11 of the substrate 1 formed by using different materials. Figure 8 Among them, curve C4 represents the temperature change on the first surface 11 of the substrate 1 made of pure calcium titanate. Refer to

[0095] It can be seen that the farther away from the axis a2 of the first surface 11 (i.e., the geometric center of the first surface 11), the lower the temperature. Moreover, the closer to the edge of the first surface 11, the faster the temperature drops. The difference between the temperature at a distance of about 1.7 cm from the axis a2 and the temperature at the axis a2 has exceeded the preset tolerance range. It can be seen that using a substrate 1 made of pure calcium titanate will cause uneven heating of the workpiece to be processed (such as a substrate), affecting process consistency.

[0095] Curve C5 represents the temperature change on the first surface 11 of the substrate 1 made of pure silicon dioxide. Refer to Figure 8It can be seen that the farther away from the axis a2 of the first surface 11 (i.e., the geometric center of the first surface 11), the lower the temperature. Moreover, the closer to the edge of the first surface 11, the faster the temperature drop trend. The difference between the temperature at a distance of about 1.7 cm from the axis a2 and the temperature at the axis a2 has exceeded the preset tolerance range. It can be seen that using a substrate 1 made of pure silica will also cause uneven heating of the workpiece to be processed (such as a substrate), affecting process consistency.

[0096] Curve C6 represents the temperature change on the first surface 11 of the substrate 1 formed by respectively using calcium titanate, silica, and copper as the first component 21, the second component 22, and the third component 23, and splicing them together in pairs according to the preset heat transfer optimization surface 4 (for example, obtained by rotating the preset heat transfer optimization curve 6 in Figure 9 around the axis a2 for one full circle). Refer to Figure 8 It can be seen that as the distance from the axis a2 of the first surface 11 (i.e., the geometric center of the first surface 11) increases, the temperature of the first surface 11 basically remains unchanged. In other words, the temperature distribution on the first surface 11 is basically uniform and consistent. At this time, the splicing method of the first component 21, the second component 22, and the third component can be as shown in Figure 9 .

[0097] From the above two simulation experiments, by studying the comparison of heat transfer data between metal and metal, and inorganic non-metal and inorganic non-metal, and optimizing the preset heat transfer optimization surface 4 between various materials, the effect of optimizing the heat transfer uniformity of the splicing surface 3 is achieved. From the data shown in Figure 6 and Figure 8 , it shows that the implementation scheme of the present invention can effectively improve the uniformity of the surface temperature of the workpiece table 101.

[0098] Therefore, by adopting this implementation scheme, by splicing multiple components 2 with different thermal conductivities together to form the substrate 1, and making the curved surface shape of the splicing surface of any two adjacent components 2 fit the preset heat transfer optimization surface 4, the heat transfer of the substrate 1 can be made more uniform, and then the workpiece to be processed carried on the substrate 1 is heated more evenly. Thus, the uniformity of the surface temperature of the substrate 1 can be optimized, and the workpiece to be processed carried on the workpiece table 101 is heated or cooled more evenly.

[0099] Furthermore, the optimized substrate 1 material uniform heat diffusion solution provided in this embodiment can better reduce the temperature deviation at various positions on the surface of the substrate 1 (for example, the first surface 11) during heat diffusion, and reduce the lattice damage and other defects caused by the temperature difference on the surface of the workpiece to be processed (for example, the substrate). Further, in the substrate 1 of this embodiment, by adjusting the shape of the splicing surface 5 of each component 2 with different thermal conductivities, uniform heat transfer can be achieved without additionally installing a heating compensation mechanism, nor changing the original functional structure of the workpiece table 101. Directly installing the substrate 1 provided in this embodiment can ensure the temperature balance of the substrate, with a simple structure and low production cost.

[0100] Furthermore, according to different preset optimized heat transfer surfaces 4, the splicing surface 3 can be flexibly changed to the required shape, and the prepared substrate 1 is not limited by size and can be compatible with most semiconductor process equipment.

[0101] Furthermore, in this embodiment, through preset parameter design, the shape of the splicing surface 3 of any two adjacent components 2 can be adjusted to achieve the desired temperature distribution on the surface of the substrate 1, thereby realizing the temperature field control in the workpiece to be processed.

[0102] Furthermore, this embodiment can be applied to the application scenarios of heating-type workpiece tables and can also be applied to cooling-type workpiece tables.

[0103] Figure 10 It is a schematic diagram of a semiconductor process equipment 100 according to an embodiment of the present invention.

[0104] The semiconductor process equipment 100 can be, for example, a lithography machine table, an etching machine table, etc.

[0105] Specifically, this embodiment can include a process chamber 102. The process chamber 102 can be surrounded by a heat insulation cover 104. The heat insulation cover 104 can be used to prevent heat from leaking out of the process chamber 102 and keep the entire process environment warm.

[0106] Furthermore, the semiconductor process equipment 100 can also be provided with Figures 1 to 5 the workpiece table 101 as shown. The workpiece table 101 is accommodated in the process chamber 102.

[0107] Furthermore, the semiconductor process equipment 100 can also be provided with a heat source 103, and the heat source 103 is arranged in the process chamber 102 and above the substrate 1.

[0108] Furthermore, the heat source 103 operates at a preset total heating power.

[0109] Further, the preset heat transfer optimization surface 4 is related to the processing technology of the semiconductor process equipment 100. The processing technology can be, for example, a lithography process, an etching process, etc. The preset heat transfer optimization surface 4 can be determined according to the actual processing technology of the semiconductor process equipment 100.

[0110] Further, the plurality of components 2 includes a first component 21 for forming the first surface 11, and the material of the first component 21 is determined according to the processing technology of the semiconductor process equipment 100.

[0111] In some embodiments, if the processing technology of the semiconductor process equipment 100 requires the substrate 1 to be a conductor, then at least the material of the first component 21 can be a metal, such as molybdenum metal, copper metal, etc. Further, the material of the second component 22 can also be a metal, so that the second surface 12 can conduct electricity to the first surface 11.

[0112] In some embodiments, if the processing technology of the semiconductor process equipment 100 requires the substrate 1 to be an insulator, then at least the material of the first component 21 can be an inorganic non-metal, such as calcium titanate, silicon dioxide, etc. Further, the second component 22 can also be made of an insulating material, such as sapphire, graphite, etc., so that the second surface 12 does not conduct electricity to the first surface 11. Further, in the area not in contact with the substrate and the non-conductive area, materials with other thermal conductivity coefficients (for example, the third component 23) can be added to fit the optimal preset heat transfer optimization surface.

[0113] As above, by adopting this implementation scheme, according to the specific application scenario (for example, the processing technology of the semiconductor process equipment 100, the material of the workpiece to be processed that needs to be heated, etc.), the heat transfer equations of various materials with different thermal conductivity coefficients are calculated, the preset heat transfer optimization curve 6 (or the preset heat transfer optimization surface 4) is optimized, the surface shape of the splicing surface 3 is determined according to the preset heat transfer optimization curve 6, and each part of the component 2 is manufactured and assembled together to form the substrate 1. After the substrate 1 receives the heat provided by the heat source 103, the temperature distribution on the surface of the substrate 1 is more uniform and consistent. Further, the heating or heat dissipation of the workpiece to be processed placed on the substrate 1 of the workpiece table 101 will also be more uniform.

[0114] Further, this implementation scheme adopts a pure passive heat uniformity scheme. The heat distribution curve is determined according to the requirements of specific application scenarios such as the processing technology of the semiconductor process equipment 100. Through a calculation method, the places with uneven heat distribution are compensated in advance with different materials, and there is no need to set up an additional heating module or heat compensation module to actively adjust the temperature. Thus, through the passive heat dissipation structure, uniform heat diffusion is achieved in a low-cost and low-complexity manner.

[0115] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A workpiece stage, comprising: A substrate having opposite first and second surfaces, wherein the first surface is for carrying a workpiece to be processed; Characterized in that the substrate comprises: A plurality of components spliced pairwise, and the plurality of components have different thermal conductivities; Wherein, for any two adjacent components among the plurality of components, the curved surface shape of the splicing surface of the two components conforms to a preset heat transfer optimization curved surface, and the preset heat transfer optimization curved surface is used to characterize the curved surface shape of the splicing surface when the temperature difference between any two positions on the first surface falls within a preset tolerance range.

2. The workpiece table according to claim 1, characterized in that, The plurality of components form a plurality of splicing surfaces, the number of the preset heat transfer optimization curved surfaces is multiple, and the multiple preset heat transfer optimization curved surfaces and the plurality of splicing surfaces correspond one by one.

3. The workpiece table according to claim 1, characterized in that, The preset heat transfer optimization curved surface is fitted according to the heat transfer equation of the two components under a preset total heating power.

4. The workpiece table according to claim 1, wherein The first surface and the second surface are circular. In a cross-section of the substrate along the radial direction of the circle, for any two adjacent components among the plurality of components, the curvature change of the splicing seam of the two components satisfies a preset heat transfer optimization curve, wherein the preset heat transfer optimization curved surface includes a plurality of the preset heat transfer optimization curves.

5. The workpiece table according to claim 4, characterized in that, The preset heat transfer optimization curve is fitted according to the heat transfer equation of the two components under a preset total heating power.

6. The workpiece table according to claim 1, characterized in that, For any two adjacent components among the plurality of components, the difference between the thermal conductivities of the two components is greater than a preset threshold.

7. The workpiece table according to claim 6, characterized in that, The plurality of components include a first component and a second component. The first surface includes a first region and a second region. The first component includes a first concave portion protruding towards the first region and a first convex portion protruding in a direction away from the second region. The second component includes a second convex portion for filling the first concave portion and a second concave portion for avoiding the first convex portion. The first concave portion and the second convex portion, the first convex portion and the second concave portion cooperate to make the temperature difference between the first region and the second region fall within the preset tolerance range.

8. The workpiece table according to claim 1, characterized in that, The plurality of components include a first component and a second component, and both the first component and the second component are made of metal materials.

9. The workpiece table according to claim 8, characterized in that, The first surface and the second surface are formed by different components.

10. The workpiece table according to claim 1, characterized in that, The plurality of components include: A first component for forming the first surface, and the first component is made of an inorganic non-metallic material; A second component for forming the second surface, and the first component and the second component are partially spliced, and the second component is made of an inorganic non-metallic material; A third component located between the non-spliced parts of the first component and the second component, and the third component is made of a metal material.

11. The workpiece table according to claim 10, characterized in that, The third component is closer to the edge of the substrate than to the center of the substrate.

12. The workpiece table according to claim 1, characterized in that, The fixed connection method between adjacent components is at least selected from: friction welding, tight fit, and seamless welding.

13. A semiconductor processing apparatus, characterized in that, Comprising: A process chamber; The workpiece stage according to any one of claims 1 to 12 above, and the workpiece stage is accommodated in the process chamber; A heat source, which is arranged in the process chamber and above the substrate.

14. The semiconductor process equipment according to claim 13, wherein The preset heat transfer optimization surface is related to the processing technology of the semiconductor process equipment.

15. The semiconductor processing equipment according to claim 13, wherein, The multiple components include a first component, the first component is used to form the first surface, and the material of the first component is determined according to the processing technology of the semiconductor process equipment.

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