Vacuum suction system and method

Abstract

A vacuum suction system for suctioning and desorption of a wafer placed on a mounting surface of a vacuum suction heater (200) having an air vent (201) in a reaction chamber (100) having an air bleed port (101), the system comprising: a first pipe (A) for fluidly connecting the air bleed port (101) of the reaction chamber (100) to a vacuum pump (300); a second pipe (B) for fluidly connecting the air vent (201) of the vacuum suction heater (200) to the vacuum pump (300); and a third pipe (C) connected to the second pipe (B) for supplying gas from a gas source (400) to the vacuum suction system.

Description

[Technical field]

[0001] This application relates to an apparatus for heating a wafer in a semiconductor processing chamber, and in particular to a vacuum suction heater. This application also relates to a vacuum suction system that can be used in conjunction with the vacuum suction heater, and a method of suctioning a wafer using the vacuum suction system.

[0002] Background technology A wafer or substrate is a base material for fabricating semiconductor devices. To fabricate semiconductor devices (e.g., integrated circuits, semiconductor light-emitting devices, etc.), the wafer or substrate must be placed in a semiconductor processing chamber (also called a reaction chamber) to undergo heating and deposition processes (e.g., chemical vapor deposition (CVD), plasma enhanced chemical vapor deposition (PECVD), etc.) to deposit thin films on the surface of the wafer or substrate. During processing, the wafer can be fixed to a heater in the processing chamber by vacuum suction or the like.

[0003] However, conventional vacuum suction heaters, vacuum suction systems and methods have many drawbacks.

[0004] For example, because the wafer mounting surface of the heater and the wafer are in surface contact, uneven contact is likely to occur. For example, when the wafer is placed on the mounting surface, the two may not come into perfect, uniform contact due to surface roughness of the mounting surface and the wafer itself, processing errors, etc., and some positions may float in the air or uneven gaps may exist depending on the position.

[0005] In such a case, when the heater heats up, each position of the wafer may be heated unevenly, which may result in a poor heating effect and even affect the pass rate of the wafer; meanwhile, the vacuum suction force on the wafer may be insufficient during operation, which may result in a poor suction effect, and the wafer may even move on the mounting surface, which is especially likely in a processing chamber with a large air flow rate and high pressure.

[0006] In addition, some vacuum suction structures in vacuum suction heaters (e.g., through holes in the heating plate, suction pipes inside the heating plate, etc.) are not easy to process due to their small size or deep depth, making processing difficult and costly.

[0007] In addition, in the conventional vacuum suction system, the pressure difference between the rear surface of the wafer (i.e., the surface that contacts the wafer placement surface of the heater) and the front surface can be controlled by sucking the gas (air) in the suction pipe line inside the heater only with a vacuum pump, so that the suction force on the wafer can be controlled only by operating the vacuum pump (or the valve of the vacuum pump pipe line) to control the air pressure in the suction pipe line inside the heater and control the pressure difference between the rear surface and the front surface of the wafer during the process of suction and desorption of the wafer. However, this method makes it very inconvenient (or impossible) to adjust the suction force on the wafer as needed, and in the process of desorption of the wafer, the pressure on the rear surface of the wafer can be made almost equal to the pressure on the front surface only by closing the vacuum pump (or the valve of the vacuum pump pipe line) and automatically flowing the gas in the reaction chamber to the rear surface of the wafer through the suction pipe line inside the heater, and the wafer can be desorbed, but this whole process takes time, which reduces the work efficiency.

[0008] Therefore, in order to solve the above technical problems, it is necessary to improve the vacuum suction heater, the vacuum suction system, and the method of suctioning a wafer using the vacuum suction system in the prior art.

[0009] Contents of the invention The present application aims to solve at least one of the problems of the prior art described above, and to provide an improved vacuum suction heater, which can achieve uniform point contact between the wafer placed on the mounting surface and the mounting surface, and thus can not only efficiently suction the wafer during operation and prevent the wafer from moving on the mounting surface of the heater (even in a reaction chamber with a high gas flow rate and high pressure), but also can uniformly heat the entire wafer, improving the product quality of the wafer.

[0010] The present application also provides a vacuum suction system for suctioning a wafer, and during both the process of suctioning and desorption of the wafer, the air pressure in the suction pipe inside the heater can be easily adjusted, and the pressure difference between the back surface and front surface of the wafer can be adjusted (i.e., the magnitude of the suction force can be adjusted), thereby satisfying various suction needs for the wafer (for example, depending on the wafer processing process, a large suction force may be required, and a small suction force may be required).In addition, during the process of desorption of the wafer, gas can be introduced to rapidly increase the pressure on the back surface of the wafer to the same level as or higher than the pressure on the front surface, so that the suction force can be removed in a short period of time and the wafer can be detached, which is advantageous for improving work efficiency.

[0011] The present application also provides a method for suctioning a wafer using the above-mentioned vacuum suction system, which can effectively achieve the purpose of adjusting the suction force for suctioning a wafer, and has a wide range of applications, thereby contributing to improving the work efficiency of wafer processing.

[0012] Some embodiments of the present application provide a vacuum suction system for adsorbing and desorbing a wafer placed on a mounting surface of a vacuum adsorption heater having an air vent in a reaction chamber having an air bleed port, the system comprising: a first pipeline for fluidly connecting the air bleed port of the reaction chamber to a vacuum pump; a second pipeline for fluidly connecting the air vent of the vacuum adsorption heater to the vacuum pump; and a third pipeline connected to the second pipeline for supplying gas from a gas source to the vacuum suction system.

[0013] In some embodiments of the present application, a first valve is disposed in the second conduit near the vent, and the third conduit is connected to the second conduit downstream of the first valve.

[0014] In some embodiments of the present application, a second valve is disposed in the third line. In one embodiment, the third line further includes an air pressure controller for adjusting the flow rate of the gas supplied to the vacuum suction system, the air pressure controller including a mass flow controller, a flow rate adjustable valve, and an air pressure measuring device.

[0015] In one embodiment, a throttle valve is disposed in the first line, the second line branches into a first manifold line and a second manifold line downstream of the first valve, the other end of the first manifold line is connected to the first line between the extraction port of the reaction chamber and the throttle valve, a third valve is disposed in the first manifold line, the other end of the second manifold line is connected to the vacuum pump, and a fourth valve is disposed in the second manifold line.

[0016] In one embodiment, a pressure measuring device is further disposed in the second manifold line.

[0017] In one embodiment, the first valve, the second valve, the third valve and the fourth valve are all electro-pneumatic valves.

[0018] Some embodiments of the present application also provide a method for adsorbing a wafer using the vacuum adsorption system described in any of the embodiments of the present application, comprising: supplying gas from the gas source through the second pipe and the third pipe to an adsorption pipe inside the vacuum adsorption heater, the adsorption pipe being in fluid communication with the vent hole, during the process of adsorbing and / or desorbing the wafer, to adjust the pressure difference between the back surface and the front surface of the wafer.

[0019] In some embodiments of the present application, in the process of adsorbing the wafer, gas from the gas source is supplied to the adsorption pipeline through the second pipeline and the third pipeline so that the pressure on the back surface of the wafer is 30 to 150 Torr lower than the pressure on the front surface of the wafer.

[0020] In some embodiments of the present application, in the process of desorbing the wafer, the gas from the gas source is supplied to the adsorption line through the second line and the third line so that the pressure on the backside of the wafer is higher than the pressure on the front side of the wafer, for example, 5 to 10 Torr higher than the pressure on the front side of the wafer.

[0021] Some embodiments of the present application provide a method for chucking a wafer using the vacuum chucking system according to any of the embodiments of the present application, comprising: (a) a wafer placing step of placing the wafer on a placing surface of the vacuum suction heater in the reaction chamber when the vacuum suction system is in an off state; (b) a wafer suction step of activating the vacuum suction system, and continuously sucking gas in a suction pipe line fluidly communicating with the vent hole inside the vacuum suction heater through the second pipe line so that the pressure on the back surface of the wafer is smaller than the pressure on the front surface of the wafer, thereby suctioning the wafer onto a mounting surface of the vacuum suction heater; (c) a wafer detachment step of stopping suction of gas in the suction pipeline inside the vacuum suction-type heater after the processing of the wafer is completed, supplying gas from the gas source to the suction pipeline through the second pipeline and the third pipeline so that the pressure on the back surface of the wafer becomes higher than the pressure on the front surface of the wafer, and detaching the wafer.

[0022] In some embodiments, the method further comprises: (a1) before step (a), heating the mounting surface of the vacuum adsorption heater (for example, heating to 450 to 500° C.) and creating a vacuum state in the reaction chamber via the vacuum pump; (a2) After step (a) and before step (b), the method further comprises at least one of the steps of injecting a gas into the reaction chamber to increase the air pressure in the reaction chamber.

[0023] In some embodiments, step (b) is initiated when the air pressure in the reaction chamber rises above a threshold value (e.g., 100 Torr) in step (a2). In some embodiments, in step (b), while continuously sucking gas in the adsorption pipeline in the vacuum adsorption heater through the second pipeline using the vacuum pump, gas from the gas source is supplied into the adsorption pipeline through the second pipeline and the third pipeline so that the pressure on the back surface of the wafer is 30 to 150 Torr lower than the pressure on the front surface.

[0024] As described above, in some embodiments of the present application, a throttling valve is disposed in the first conduit, a first valve is disposed in the second conduit near the vent port, the third conduit is connected to the second conduit downstream of the first valve, a second valve is disposed in the third conduit, the second conduit branches into a first manifold conduit and a second manifold conduit downstream of the first valve, the other end of the first manifold conduit is connected to the first conduit between the extraction port of the reaction chamber and the throttling valve, a third valve is disposed in the first manifold conduit, the other end of the second manifold conduit is connected to the vacuum pump, and a fourth valve is disposed in the second manifold conduit.

[0025] In some embodiments, during execution of step (a1), the first valve, the second valve, the third valve, and the fourth valve are all off, and the throttle valve is on.

[0026] In some embodiments, during step (b), the first valve, the second valve and the fourth valve are all on, and the third pneumatic valve is off.

[0027] In some embodiments, in step (b), the flow rate of the gas in the third pipe (C) is adjusted so that the pressure on the back surface of the wafer is 30 to 150 Torr lower than the pressure on the front surface.

[0028] In some embodiments, during step (c), the first valve, the second valve and the third valve are all on, and the fourth valve is off.

[0029] In some embodiments, in step (c), the flow rate of the gas in the third line is adjusted so that the pressure on the backside of the wafer is equal to or higher than the pressure on the front side of the wafer, for example, the flow rate of the gas in the third line (C) is adjusted so that the pressure on the backside of the wafer is 5 to 10 Torr higher than the pressure on the front side of the wafer.

[0030] Description of the drawings In order to more clearly explain specific embodiments of the present application and the resulting technical effects, specific embodiments of the present application will be described below in conjunction with the accompanying drawings. For clarity of presentation and ease of arrangement of the drawings, these accompanying drawings are not drawn to perfect proportion, for example, some drawings are enlarged to show local details and some drawings are reduced to show the overall structure. For clarity, the accompanying drawings may not show all assemblies of a given device or apparatus. Finally, the same accompanying drawing symbols are used to denote the same features throughout the specification and the accompanying drawings. In the drawings: [Brief description of the drawings]

[0031] [Figure 1] FIG. 1 is a three-dimensional schematic diagram of the overall structure of a vacuum adsorption heater according to some embodiments of the present application. [Diagram 2] FIG. 2 is a top view of the heating plate of the vacuum suction heater shown in FIG. 1, and more clearly shows the first distribution manner of the recesses and protrusions on the top surface of the heating plate body (i.e., the surface on which the wafer is placed). [Figure 2A] FIG. 2A is an enlarged view of A of FIG. 2, specifically showing the through hole in the heating plate disposed within the annular recess of the innermost ring and having a diameter greater than the width of the annular recess. [Diagram 3] FIG. 3 is also a top view of the heating plate similar to FIG. 2, showing a second distribution method of the recesses and protrusions on the top surface of the heating plate. [Figure 4] FIG. 4 is also a top view of the heating plate similar to FIG. 2, showing a third distribution method of the recesses and protrusions on the top surface of the heating plate. [Diagram 5] FIG. 5 is also a top view of the heating plate similar to FIG. 2, and shows a fourth distribution method of the recesses and protrusions on the top surface of the heating plate. [Figure 6] FIG. 6 is also a top view of the heating plate similar to FIG. 2, and shows the fifth distribution method of the recesses and protrusions on the top surface of the heating plate. [Figure 7] FIG. 7 is also a top view of the heating plate similar to FIG. 2, and shows a sixth distribution method of the recesses and protrusions on the top surface of the heating plate. [Figure 8] FIG. 8 is also a top view of the heating plate similar to FIG. 2, showing the seventh distribution method of the recesses and protrusions on the top surface of the heating plate. [Figure 9] FIG. 9 is a front view of the vacuum adsorption heater shown in FIG. 1, showing the structure of the front side of this vacuum adsorption heater. [Figure 10] FIG. 10 is a cross-sectional view taken along line BB of FIG. 9, showing the internal structure of this vacuum adsorption heater at the cross-sectional position. [Figure 11] FIG. 11 is a left side view of the vacuum adsorption heater shown in FIG. 1, showing the structure of the side of this heater. [Figure 12] FIG. 12 is a cross-sectional view taken along the line CC in FIG. 11, showing the internal structure of this vacuum adsorption heater at the cross-sectional position. [Figure 12A] FIG. 12A is an enlarged view of D in FIG. 12, and shows a schematic diagram of the vertical structure of the protrusions, recesses, and through-holes. [Figure 13] FIG. 13 is a schematic diagram of the structure of a vacuum suction system according to some embodiments of the present application. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] Specific embodiments Hereinafter, the embodiments of the present application will be described in detail in conjunction with the accompanying drawings. Various aspects of the present application will be more easily understood by reading the following description of specific embodiments with reference to the accompanying drawings. These embodiments are merely illustrative and are used only to interpret and explain the technical ideas of the present application, and do not limit the present application. Those skilled in the art can make various modifications and conversions (such as changing the size and / or layout of the concave and convex parts on the upper surface of the heating plate body) based on these embodiments. All technical solutions obtained by conversion in an equivalent manner fall within the protection scope of the present application.

[0033] The names of various parts used in this manual are for explanatory purposes only and have no limiting role, and different manufacturers may use different names to refer to parts with the same function.

[0034] Vacuum adsorption heater Fig. 1 is a three-dimensional schematic diagram of the overall structure of a vacuum adsorption heater according to an embodiment of the present application. As shown in Fig. 1, this vacuum adsorption heater mainly includes a heating dish 10. The heating dish 10 includes a substantially disk-shaped main body 1 and a support shaft 2 arranged below the main body 1.

[0035] As shown in Figure 1, the body 1 has an upper surface 11 on which a wafer is placed. During operation, the body 1 of the heating dish 10 is placed in a reaction chamber, and a wafer (not shown) can be placed on the upper surface 11 of the body 1 by a transport device such as a robot hand and fixed by vacuum suction. After the wafer is fixed, operations such as deposition processing can be performed.

[0036] Referring to Fig. 1 in conjunction with Figs. 9 to 12, in some embodiments of the present application, the main body 1 of the heating dish 10 and the support shaft 2 arranged below the main body 1 are integrally formed. For example, both can be made of ceramics and integrally formed by bonding, welding, or the like. Compared to a heating dish employing a separate structure (i.e., a structure in which the main body and the support shaft are detachably assembled), the integrally formed structure of the present application not only does not require the steps of attaching, fixing, and sealing the two, but also does not require a sealing element between the two, significantly improving the sealing performance and effectively enhancing the effect of vacuum suction.

[0037] Continuing to refer to Fig. 1 and Fig. 9 to Fig. 12, in the external structure, the vacuum adsorption heater further includes a cooling block 50 disposed outside the support shaft 2 and at least partially surrounding the support shaft 2, and a fixing block 60 disposed outside the cooling block 50 and sandwiching the cooling block 50. The fixing block 60 is used to fix the vacuum adsorption heater to a machine base. The specific structures of the cooling block 50 and the fixing block 60 can adopt designs known in the art, and will not be described again here.

[0038] In the internal structure, the vacuum suction heater further includes a heating element (not shown) disposed inside the body 1, and a heating rod 40 electrically connected to the heating element. The heating element can include, but is not limited to, a resistance wire, and the heating rod 40 can include materials with good electrical conductivity, such as copper, nickel, etc. The heating element, the heating rod 40, and the electrical connection between them can adopt designs known in the art, and will not be described again here.

[0039] As shown in Figs. 10 and 12, the support shaft 2 has a hollow structure and can accommodate a plurality of quartz blocks 20 and / or polyether ether ketone (PEEK) blocks 30 stacked in sequence inside. The heating rod 40 is disposed inside the support shaft 2, passes through the quartz block 20 and / or the PEEK block 30, and can be electrically connected to an external power source. When the power source is turned on, the heating element generates heat and transfers the heat to the wafer on the body 1 of the heating dish 10. The heating rod 40 also generates heat. The quartz block 20 and the PEEK block 30 surrounding the heating rod 40 keep the heat inside the support shaft 2 from dissipating much, and contribute to transferring the heat to the wafer and heating it. The quartz block 20 and the PEEK block 30 are also used to achieve electrical insulation between the assemblies inside the support shaft 2.

[0040] In the present application, the structure of the body 1 of the heating dish 10 (particularly the upper surface 11 on which the wafer is placed) is specially designed. Specifically, it is as follows.

[0041] 1, 2 and 2A, FIG. 2 is a top view of the heating dish 10 shown in FIG. 1, and FIG. 2A is an enlarged view of A in FIG. 2. In the present application, the body 1 of the heating dish 10 further has the following structure: a plurality of recesses 12 extending downward from the upper surface 11 and at least partially in fluid communication with one another; one or more through holes 13 in fluid communication with at least one recess 12; ◆ It has a plurality of protrusions 14 arranged on the upper surface 11 for supporting the wafer.

[0042] In some embodiments provided herein, the plurality of recesses 12 and the plurality of protrusions 14 are both distributed approximately uniformly on the upper surface 11. It should be understood by those skilled in the art that the plurality of recesses 12 and the plurality of protrusions 14 may not be distributed uniformly, and either one may be distributed uniformly. For example, in some embodiments, the plurality of recesses 12 are distributed approximately uniformly, but the plurality of protrusions 14 are distributed unevenly (e.g., the protrusions in the middle portion are dense and the protrusions around the periphery are sparse), and in some embodiments, the plurality of protrusions 14 are distributed approximately uniformly, but the plurality of recesses 12 are distributed unevenly (e.g., the recesses are denser closer to the middle portion and sparser toward the periphery).

[0043] Unlike the prior art, in the present application, since the upper surface 11 has the convex portions 14, the wafer and the upper surface 11 of the heating dish body can form uniform point contact with each other and have a uniform gap between them; that is, these convex portions 14 make the contact between the wafer and its supporting surface (i.e., the upper surface 11 of the body 1) more uniform, which helps to provide uniform suction force and uniform heating to each part of the wafer, thereby facilitating wafer processing and contributing to ensuring the quality of the film formation on the wafer surface and improving its pass rate.

[0044] In some embodiments of the present application, as shown in Figures 1 and 2, the multiple recesses 12 include multiple annular recesses 121 arranged concentrically and radial recesses 122 fluidly connecting the annular recesses 121. In one embodiment, all the radial recesses 122 fluidly connect the adjacent annular recesses 121, thereby connecting all the annular recesses 121 and the radial recesses 122. Thus, all the recesses 12 are completely fluidly connected. Therefore, by applying a vacuum to one recess 12, all the recesses 12 can be applied to a vacuum, thereby obtaining a suction force to the wafer.

[0045] In some embodiments of the present application, the annular recesses 121 and the radial recesses 122 have a width of 0.5-1.5 mm, a depth of 1.0 mm or less, and a distance between adjacent annular recesses 121 of 10-50 mm. More preferably, the annular recesses 121 and the radial recesses 122 have a width of 0.5-1.0 mm, a depth of 0.5 mm or less, and a distance between adjacent annular recesses 121 of 15-50 mm. Recesses in the above size ranges are easy to process and contribute to efficient wafer adsorption. For illustrative purposes only, the accompanying drawings of the present application show a specific number of annular recesses 121 and radial recesses 122. It should be understood that the heating dish 10 can have any suitable number of annular recesses 121 and radial recesses 122.

[0046] Further, as shown in FIG. 2 and FIG. 2A, in some embodiments of the present application, the main body 1 may be provided with only one through hole 13, and this through hole 13 is disposed in one recess 12, for example, disposed in the innermost annular recess 121 as shown in FIG. 2A, and is in fluid communication with the annular recess 121. In other embodiments, the through hole 13 may also be disposed in other recesses 12. Also, as shown in FIG. 2A, the diameter of this through hole 13 may be larger than the width of the recess 12, for example, 0.8 to 1.8 mm. The through hole 13 having a diameter within this size range is easy to process because the through hole is deep, and a good adsorption effect can be obtained. Also, by providing only one through hole 13, the processing process can be simplified and the processing cost can be reduced. In other embodiments, the main body 1 may be provided with a plurality of through holes 13.

[0047] In some embodiments of the present application, each of the protrusions 14 may be substantially circular as shown in the figures, but the present application is not limited thereto. When the body 10 of the heating dish 1 is produced, the protrusions 14 can be directly sintered onto the upper surface 11. In some embodiments, each of the protrusions 14 has a diameter of 1.0 to 3.0 mm, a height of 0.2 mm or less, and a distance between adjacent protrusions 14 of 3 to 20 mm. Protrusions having this size range facilitate processing and molding (e.g., facilitate the design of a mold for the body 1 of the heating dish 10) and can effectively achieve uniform contact with the wafer. Preferably, each of the protrusions 14 has a diameter of 1.5 to 2.5 mm, a height of 0.1 mm or less, and a distance between adjacent protrusions 14 of 5 to 15 mm. Protrusions having this size range also contribute to production processing and provide uniform contact with the wafer.

[0048] In order to achieve better technical effects, the combination of the distribution of the recesses 12 and the distribution of the protrusions 14 should be considered when designing the structure of the upper surface 11 of the body 1 of the heating plate 10, and some exemplary considerations are described below in conjunction with the accompanying drawings. It should be understood that the distribution manner of the recesses 12 and the protrusions 14 is not limited to these several considerations.

[0049] In the first design, as shown in Figures 2 to 4, a total of seven annular recesses 121 are provided on the upper surface 11 of the main body 1. Both the annular recesses 121 and the radial recesses 122 have a width of 1.0 mm and a depth of 0.5 mm, and the interval between adjacent annular recesses 121 is 21.5 mm. In this design, the annular recesses 121 are closely spaced, so that the suction force during operation becomes more uniform, and the suction effect on the wafer is improved.

[0050] 2, each protrusion 14 has a diameter of 2.0 mm and a height of 0.1 mm, and the multiple protrusions 14 are distributed in the circumferential direction to form multiple concentric circles, with the interval between adjacent protrusions 14 arranged on the same circumference and the interval between adjacent circumferences being 7 mm. This structure makes it possible to realize uniform support of the wafer from the circumferential direction.

[0051] In a second embodiment of this invention, as shown in FIG. 3, each protrusion 14 has a diameter of 2.0 mm and a height of 0.1 mm, the multiple protrusions 14 are distributed in a triangular shape (for example, the three nearest protrusions 14 may form an equilateral triangle), and the spacing between adjacent protrusions 14 is 10 mm.

[0052] In a third embodiment of this invention, as shown in FIG. 4, each protrusion 14 has a diameter of 2.0 mm and a height of 0.1 mm, the multiple protrusions 14 are distributed in a triangular shape (for example, the three nearest protrusions 14 may form an equilateral triangle), and the spacing between adjacent protrusions 14 is 5 mm.

[0053] In the second idea, as shown in Figures 5 to 8, a total of four annular recesses 121 are provided on the upper surface 11 of the main body 1. The annular recesses 121 and the radial recesses 122 are both 1.0 mm wide and 0.5 mm deep, and the interval between adjacent annular recesses 121 is 43 mm. In this idea, the annular recesses 121 are sparser, and the heating plate 10 having such a structure is easier to manufacture, and the mold design and manufacturing are more convenient, thereby reducing the manufacturing cost.

[0054] In a first embodiment of such a concept, as shown in Fig. 5, each protrusion 14 has a diameter of 2.0 mm and a height of 0.1 mm, and the multiple protrusions 14 are distributed in the circumferential direction to form multiple concentric circles, with the interval between adjacent protrusions 14 arranged on the same circumference and the interval between adjacent circumferences being 7 mm. This structure makes it possible to realize uniform support of the wafer from the circumferential direction.

[0055] In a second embodiment of this invention, as shown in Fig. 6, each of the protrusions 14 has a diameter of 2.0 mm and a height of 0.1 mm, and the multiple protrusions 14 are distributed in the circumferential direction to form multiple concentric circles, with the interval between adjacent protrusions 14 arranged on the same circumference and the interval between adjacent circumferences being 15 mm. With this configuration, the protrusions 14 are more sparse, making processing easier.

[0056] In a third embodiment of this invention, as shown in FIG. 7, each protrusion 14 has a diameter of 2.0 mm and a height of 0.1 mm, the multiple protrusions 14 are distributed in a triangular shape (for example, the three nearest protrusions 14 may form an equilateral triangle), and the spacing between adjacent protrusions 14 is 10 mm.

[0057] In a fourth embodiment of such a concept, as shown in FIG. 8, each protrusion 14 has a diameter of 2.0 mm and a height of 0.1 mm, the multiple protrusions 14 are distributed in a triangular shape (for example, the three nearest protrusions 14 may form an equilateral triangle), and the spacing between adjacent protrusions 14 is 5 mm.

[0058] Those skilled in the art will understand that the spacing between adjacent annular recesses 121 is the distance between corresponding points on the two annular recesses 121, i.e., the distance between corresponding points on the outermost edge (or centerline or innermost edge) of one annular recess 121 and corresponding points on the outermost edge (or centerline or innermost edge) of the other annular recess 121. The width of a recess is the distance between corresponding points on both edges of the recess, and the depth is the distance from the bottom surface of the recess to the top end of the recess. Similarly, the spacing between adjacent protrusions 14 is the distance between corresponding points on the two protrusions 14 (e.g., the centers of the protrusions).

[0059] Further, referring to Fig. 12 and Fig. 12A, Fig. 12 is a cross-sectional view showing a part of the internal structure of this vacuum suction heater, and Fig. 12A is an enlarged view of D in Fig. 12, particularly showing the vertical structure of the convex portion 14, the concave portion 12, and the through-hole 13 in the main body 1 of the heating plate 10. As shown in Fig. 12A, the diameter of the through-hole 13 is larger than the width of the concave portion 12. In some embodiments, the diameter of the through-hole 13 may be 0.8 to 1.8 mm. Such a size design makes it easy to process the through-hole 13 and obtains a good suction effect.

[0060] As shown in Fig. 12, this vacuum suction heater further includes a through hole 131 penetrating the quartz block 20 and / or the PEEK block 30, and the upper end of this through hole 131 is fluidly connected to the through hole 13, and the lower end can be fluidly connected to a vacuum pump during operation, so that the vacuum pump can suck gas in the recess 12 through the pipe, the through hole 131, and the through hole 13, and generate a pressure difference between the back surface and the front surface of the wafer to suction the wafer. In some embodiments, the through hole 131 has a diameter of 2 to 3 mm, and the through hole 131 of each quartz block 20 or PEEK block 30 has a depth of 20 to 25 mm. Through holes having this depth and diameter are easy to process and produce.

[0061] In order to enhance the adsorption effect, as shown in FIG. 12, this vacuum adsorption heater further includes a seal ring 16 arranged around the through hole 131 in the quartz block 20 and / or the PEEK block, which enhances the sealing effect and prevents or reduces gas leakage.

[0062] 12, the vacuum suction heater includes a seal ring 15 disposed between the heating rod 40 and the quartz block 20 and / or the PEEK block 30. The seal ring 15 is installed in the heating rod 40 with a socket, and is sandwiched between the adjacent quartz blocks 20 and / or the PEEK blocks 30 and firmly fixed.

[0063] Vacuum suction system and wafer suction method The vacuum suction system and the method of suctioning a wafer using the vacuum suction system according to the present application are described below. The vacuum suction system may be used in combination with the vacuum suction heater described in this specification to suction a wafer, or may be used in combination with a vacuum suction heater of another structure.

[0064] Referring to FIG. 13, a vacuum adsorption system according to an embodiment of the present application is shown in schematic form. This system is used to adsorb and desorb a wafer (not shown) placed on a mounting surface of a vacuum adsorption heater 200 in a reaction chamber 100 (e.g., the upper surface 11 of the body 1 of the heating dish 10 shown in FIG. 1). The reaction chamber 100 has an air extraction port 101, and the vacuum adsorption heater 200 has an air vent 201 (e.g., the air vent 201 may be fluidly connected to the through hole 131 shown in FIG. 12). In the figure, the entire vacuum adsorption heater 200 is shown to be placed in the reaction chamber 100, but in an actual product, only a part of the vacuum adsorption heater 200, for example, a part of the body 1 and the support shaft 2 of the heating dish 10 shown in FIG. 1 (e.g., a part above the cooling block 50 (including the cooling block 50)) may be placed in the reaction chamber 100.

[0065] As shown in Figure 13, this vacuum suction system is A first conduit A for fluidly connecting the extraction port 101 of the reaction chamber 100 and the vacuum pump 300; A second pipe B for fluidly connecting the vent 201 of the vacuum adsorption heater 200 and the vacuum pump 300; ◆ A third pipe C is provided, which is connected to the second pipe B and is for supplying gas from a gas source 400 to the vacuum suction system.

[0066] In some embodiments, the gas in the gas source 400 may be nitrogen, which is relatively inexpensive and chemically inert, although other gases such as helium may be employed in other embodiments.

[0067] According to the embodiment of the present application, the gas in the gas source 400 can be supplied into the vacuum suction system as needed during operation through the third pipe C fluidly coupled with the gas source 400. Therefore, when the vacuum suction system is used to suction the wafer, the air pressure in the suction pipes (e.g., the through-hole 13 and the through-hole 131 shown in FIG. 12) inside the heater can be easily adjusted during the process of suction and desorption of the wafer, thereby adjusting the pressure difference between the back surface and the front surface of the wafer, and adjusting the magnitude of the suction force. Needless to say, this helps to meet various suction needs of the wafer. For example, when the wafer processing process requires a larger suction force, only a smaller amount of gas or no gas can be introduced from the gas source 400 to ensure that the vacuum suction system generates a suction force for the wafer, while in the process requiring a smaller suction force, a larger amount of gas can be introduced from the gas source 400 into the vacuum suction system to offset a part of the suction force generated by the vacuum pump 300.

[0068] Another technical effect of the provision of the third pipeline C is that during the process of de-bonding the wafer, gas is introduced from the gas source 400 into the vacuum suction system, which supplies gas to the suction pipeline inside the heater and rapidly raises the pressure on the backside of the wafer above the pressure on the front side, thereby quickly removing the suction force on the wafer and allowing the wafer to be de-bonded. Compared with the prior art idea of ​​automatically flowing gas in the reaction chamber to the backside of the wafer by simply turning off the vacuum suction system, the present invention has greatly improved work efficiency.

[0069] The configuration of the vacuum suction system according to some embodiments of the present application will be further described below.

[0070] 13, in the vacuum adsorption system, a throttle valve TV is disposed in the first line A to control the suction of gas in the reaction chamber 100 by the vacuum pump 300. In some embodiments, the air pressure Pc in the reaction chamber 100 may be measured by an air pressure measuring device 102 (e.g., a barometer or vacuum gauge). The throttle valve TV is adjustable according to the air pressure Pc in the reaction chamber 100, and can control the gas flow rate in the first line, and thus the air pressure Pc in the reaction chamber 100 can be controlled to a desired level.

[0071] As shown in FIG. 13, a first valve CHCV-1 is disposed near the vent 201 in the second conduit B, and a third conduit C is connected downstream of the first valve CHCV-1 in the second conduit B (i.e., the side closer to the vacuum pump 300). A second valve CHCV-2 is disposed in the third conduit C. In one embodiment, an air pressure controller 401 for adjusting the flow rate of the gas supplied to the vacuum suction system is disposed in the third conduit C. As shown in the figure, the air pressure controller 401 can include a mass flow controller MFM, a flow rate adjustable valve 402, and an air pressure measurement device 403 (e.g., a barometer or vacuum gauge). Those skilled in the art will understand that the air pressure controller 401 is not limited to the configuration shown in the figure, and a conventional air pressure controller or a device having a similar function can be used as the air pressure controller 401.

[0072] 13, the second conduit B branches into a first manifold conduit B1 and a second manifold conduit B2 downstream of the first valve CHCV-1, and the other end of the first manifold conduit B1 is connected to the first conduit A between the extraction port 101 of the reaction chamber 100 and the throttle valve TV, a third valve CHCV-3 is disposed in the first manifold conduit B1, and the other end of the second manifold conduit B2 is connected to the vacuum pump 300. In one embodiment, the other end of the second manifold conduit B2 can be connected to the first conduit A between the vacuum pump 300 and the throttle valve TV. A fourth valve CHCV-4 is disposed in the second manifold conduit B2. In one embodiment, the second manifold conduit B2 may be provided with an air pressure measuring device 500 (e.g., a barometer or vacuum gauge) for measuring the air pressure Pb in the second manifold conduit B2 (reflecting the air pressure in the adsorption conduit inside the heater).

[0073] In some embodiments, the first valve CHCV-1, the second valve CHCV-2, the third valve CHCV-3, and the fourth valve CHCV-4 are electro-pneumatic valves that can be fully opened or closed as needed to allow control of the on and off of each line. More precise control can be achieved by employing electro-pneumatic valves. In other embodiments, other types of valves can be employed.

[0074] The present application also provides a method for chucking a wafer using the above vacuum chucking system, in which the pressure difference between the rear surface and the front surface of the wafer can be adjusted by supplying gas from the gas source 400 to the chucking line in the heater through the second line B and the third line C during the process of chucking and / or dechucking the wafer.

[0075] According to some embodiments of the present application, in the process of adsorbing the wafer, gas from the gas source 400 is supplied to the adsorption pipe in the heater through the second pipe B and the third pipe C, and a desired pressure difference can be maintained between the back surface and the front surface of the wafer, for example, the pressure on the back surface of the wafer can be maintained to be 30 to 150 Torr lower than the pressure on the front surface. In the process of desorbing the wafer, gas from the gas source 400 is supplied to the adsorption pipe in the heater through the second pipe B and the third pipe C, and the pressure on the back surface of the wafer can be equal to or higher than the pressure on the front surface, for example, 5 to 10 Torr higher than the pressure on the front surface. At this time, the adsorption force is completely removed, and a certain pressing force is applied to the back surface of the wafer, so that the wafer can be easily moved to the next stage.

[0076] Generally, according to some embodiments of the present application, the method of chucking a wafer using the above-mentioned vacuum chucking system mainly includes: (a) a wafer placement step of placing a wafer on a placement surface of the vacuum suction heater 200 in the reaction chamber 100 when the vacuum suction system is in an off state (i.e., the second pipe line B and the third pipe line C are in an off state); (b) a wafer suction step of activating the vacuum suction system, continuously sucking gas in the suction pipe line inside the vacuum suction heater 200 through the second pipe line B so that the pressure on the back surface of the wafer is smaller than the pressure on the front surface of the wafer, and suctioning the wafer onto the mounting surface of the vacuum suction heater 200; (c) a wafer detachment step in which, after the processing of the wafer is completed, the suction of gas in the suction pipeline inside the vacuum suction-type heater 200 is stopped, and gas from the gas source 400 is supplied through the second pipeline B and the third pipeline C into the suction pipeline inside the vacuum suction-type heater 200 so that the pressure on the back surface of the wafer becomes higher than the pressure on the front surface of the wafer, and the wafer detachment step is performed.

[0077] In some embodiments, the method also includes: (a1) before step (a), a step of heating the mounting surface of the vacuum adsorption heater 200 (for example, heating to 450 to 500° C.) and creating a vacuum state in the reaction chamber 100 via the vacuum pump 300; (a2) After step (a) and before step (b), at least one of the following steps may be included: introducing a gas into the reaction chamber 100 (which may be via another pipeline not shown) and increasing the pressure Pc in the reaction chamber 100 (if necessary, Pc can be increased to 200 to 600 Torr, and the pressure above the throttle valve TV can be up to 200 Torr).

[0078] In one embodiment of the present application, when the pressure Pc in the reaction chamber 100 rises above a threshold value (e.g., 100 Torr) in step (a2), step (b) is started. In step (b), while continuously sucking gas in the adsorption pipe line inside the vacuum adsorption heater 200 via the second pipe line B using the vacuum pump 300, gas from the gas source 400 can be supplied into the adsorption pipe line inside the vacuum adsorption heater 200 via the second pipe line B and the third pipe line C so that the pressure on the back surface of the wafer is 30 to 150 Torr lower than the pressure on the front surface. The specific pressure difference can be adjusted according to the needs of wafer adsorption.

[0079] As described above, the throttle valve TV is disposed in the first pipe A, the first valve CHCV-1 is disposed in the second pipe B near the vent port 201, the third pipe C is connected to the second pipe B downstream of the first valve CHCV-1, and the second valve CHCV-2 is disposed in the third pipe C; the second pipe B branches into a first manifold pipe B1 and a second manifold pipe B2 downstream of the first valve CHCV-1, the other end of the first manifold pipe B1 is connected to the first pipe A between the extraction port 101 of the reaction chamber 100 and the throttle valve TV, the third valve CHCV-3 is disposed in the first manifold pipe B1, and the other end of the second manifold pipe B2 is connected to the vacuum pump 300 (for example, as shown in FIG. 13, it is connected to the first pipe A between the vacuum pump 300 and the throttle valve TV), and the fourth valve CHCV-4 is disposed in the second manifold pipe. The specific operation process of these valves and the corresponding pipelines is as follows:

[0080] In step (a1), the first valve CHCV-1, the second valve CHCV-2, the third valve CHCV-3, and the fourth valve CHCV-4 are all off, the throttle valve TV is on, only the first pipe line A is in a passage state, and the vacuum pump 300 draws the reaction chamber 100 into a vacuum state. These valves also maintain this state in step (a) (i.e., the wafer mounting step) and step (a2). In step (b) (i.e., the wafer suction step), the first valve CHCV-1, the second valve CHCV-2, and the fourth valve CHCV-4 are all on, and the third valve CHCV-3 is off. The vacuum pump 300 continuously draws in the gas in the reaction chamber 100 through the first pipe line A, and maintains the pressure Pc in the reaction chamber 100 at a desired level (e.g., 200 Torr). At this time, the second pipe line B, the second manifold pipe line B2, and the third pipe line C are in a passage state, and the vacuum pump 300 sucks in the gas in the adsorption pipe line inside the vacuum adsorption heater 200 (i.e., the gas on the back surface of the wafer). At the same time, the gas source 400 may introduce gas into the vacuum adsorption system, and may control the amount of gas introduced (i.e., the flow rate of the gas in the third pipe line C) by adjusting the air pressure controller 401. The gas sucked by the vacuum pump 300 from the adsorption pipe line of the vacuum adsorption heater 200 through the second pipe line B and the second manifold pipe line B2 and the gas introduced by the gas source 400 into the adsorption pipe line through the third pipe line C make the pressure on the back surface of the wafer 30 Torr to 150 Torr lower than the pressure on the front surface. The specific pressure difference can be set as necessary.

[0081] In step (c) (i.e., wafer desorption step), the first valve CHCV-1, the second valve CHCV-2, and the third valve CHCV-3 are all on, and the fourth valve CHCV-4 is off. The vacuum pump 300 continuously sucks the gas in the reaction chamber 100 through the first pipe line A, and maintains the pressure Pc in the reaction chamber 100 at a desired level (e.g., 200 Torr). At this time, the gas in the reaction chamber 100 enters the adsorption pipe line inside the vacuum adsorption heater through the first pipe line A, the first manifold pipe line B1, and the second pipe line B and reaches the back surface of the wafer, while the external gas (e.g., nitrogen gas) from the gas source 400 enters the adsorption pipe line inside the vacuum adsorption heater through the third pipe line C and the second pipe line B and reaches the back surface of the wafer. By using these two gases, the pressure on the backside of the wafer rises rapidly and the pressure difference with the frontside is rapidly reduced, and by adjusting the air pressure controller 401 to adjust the flow rate of gas in the third pipeline C, the pressure on the backside of the wafer rises to be equal to or greater than the pressure on the frontside, for example, 5 to 10 Torr higher than the pressure on the frontside, thereby achieving the objective of quickly removing the suction force and quickly releasing the wafer. It is clear that this operating method greatly improves work efficiency.

[0082] Although the technical content and technical features of the present application have been described through the above related embodiments, the above embodiments are merely examples for implementing the present application. Those skilled in the art can make various substitutions and modifications based on the teachings and disclosures of the present application without departing from the spirit of the present application. Therefore, the embodiments disclosed in the present application do not limit the scope of the present application. On the contrary, amendments and equivalent settings that do not depart from the spirit and scope of the present application are included in the scope of the present application.

Claims

1. A vacuum suction system for suctioning and desorption of a wafer placed on a mounting surface of a vacuum suction heater (200) having an air vent (201) in a reaction chamber (100) having an air extraction port (101), comprising: a first conduit (A) for fluidly connecting the bleed port (101) of the reaction chamber (100) with a vacuum pump (300); a second pipe (B) fluidly connecting the vent (201) of the vacuum adsorption heater (200) and the vacuum pump (300); a third pipe (C) connected to the second pipe (B) for supplying gas from a gas source (400) to the vacuum suction system; A vacuum suction system comprising:

2. A first valve (CHCV-1) is disposed near the vent (201) in the second pipeline (B); 2. The vacuum suction system according to claim 1, wherein the third pipe (C) is connected to the second pipe (B) downstream of the first valve (CHCV-1).

3. 3. The vacuum suction system according to claim 2, wherein a second valve (CHCV-2) is disposed in the third pipe (C).

4. 4. The vacuum suction system according to claim 3, further comprising an air pressure controller (401) disposed in the third pipe (C) for adjusting the flow rate of the gas supplied to the vacuum suction system.

5. The vacuum suction system according to claim 4, characterized in that the air pressure controller (401) comprises a mass flow controller (MFM), a flow adjustable valve (402), and an air pressure measuring device (403).

6. A throttle valve (TV) is disposed in the first pipe (A), The second pipe (B) branches into a first manifold pipe (B1) and a second manifold pipe (B2) downstream of the first valve (CHCV-1), the other end of the first manifold pipe (B1) is connected to the first pipe (A) between the extraction port (101) of the reaction chamber (100) and the throttle valve (TV), and a third valve (CHCV-3) is disposed in the first manifold pipe (B1); The vacuum suction system according to claim 3, wherein the other end of the second manifold (B2) is connected to the vacuum pump (300), and a fourth valve (CHCV-4) is disposed in the second manifold (B2).

7. The vacuum suction system according to claim 6, further comprising an air pressure measuring device (500) disposed in the second manifold line (B2).

8. The vacuum suction system according to claim 6, wherein the first valve (CHCV-1), the second valve (CHCV-2), the third valve (CHCV-3) and the fourth valve (CHCV-4) are all electromagnetic pneumatic valves.

9. 2. A method for chucking a wafer using the vacuum chucking system according to claim 1, comprising the steps of: During the process of adsorption and / or desorption of the wafer, the pressure difference between the back surface and the front surface of the wafer is adjusted by supplying gas from the gas source (400) to an adsorption line fluidly connected to the vent hole (201) inside the vacuum adsorption heater (200) via the second line (B) and the third line (C).

10. 10. The method according to claim 9, wherein, during the process of adsorbing the wafer, gas from the gas source (400) is supplied to the adsorption line through the second line (B) and the third line (C) so that the pressure on the back surface of the wafer is 30 to 150 Torr lower than the pressure on the front surface of the wafer.

11. 10. The method according to claim 9, wherein, during the process of desorption of the wafer, gas from the gas source (400) is supplied to the adsorption line through the second line (B) and the third line (C) so that the pressure on the back surface of the wafer is equal to or greater than the pressure on the front surface of the wafer.

12. 10. The method of claim 9, wherein gas from the gas source (400) is supplied to the adsorption line through the second line (B) and the third line (C) so that the pressure at the backside of the wafer is 5-10 Torr higher than the pressure at the frontside of the wafer during the desorption process.

13. 2. A method for chucking a wafer using the vacuum chucking system according to claim 1, comprising the steps of: (a) a wafer placement step of placing the wafer on a placement surface of the vacuum suction heater (200) in the reaction chamber (100) when the vacuum suction system is in an off state; (b) a wafer suction step of activating the vacuum suction system and continuously sucking gas in a suction line fluidly connected to the vent hole (201) inside the vacuum suction heater (200) through the second line (B) so that the pressure on the back surface of the wafer is smaller than the pressure on the front surface of the wafer, thereby suctioning the wafer onto the mounting surface of the vacuum suction heater (200); (c) A wafer desorption step of stopping the suction of the gas in the adsorption pipeline inside the vacuum adsorption heater (200) after the processing of the wafer is completed, and desorbing the wafer by supplying gas from the gas source (400) to the adsorption pipeline through the second pipeline (B) and the third pipeline (C) so that the pressure on the back surface of the wafer becomes higher than the pressure on the front surface of the wafer; 23. A method comprising:

14. (a1). Before step (a), a step of heating the mounting surface of the vacuum adsorption heater (200) and evacuating the reaction chamber (100) via the vacuum pump (300); (a2). After step (a) and before step (b), injecting a gas into the reaction chamber (100) to increase the air pressure (Pc) in the reaction chamber (100).

15. 15. The method of claim 14, wherein step (b) is initiated when, in step (a2), the air pressure (Pc) in the reaction chamber (100) rises above a threshold value.

16. 16. The method of claim 15, wherein the threshold is 100 Torr.

17. 14. The method according to claim 13, wherein in step (b), while the vacuum pump (300) is continuously sucking gas in the suction line inside the vacuum suction heater (200) through the second line (B), gas from the gas source (400) is supplied into the suction line through the second line (B) and the third line (C) so that the pressure on the back side of the wafer is 30 to 150 Torr lower than the pressure on the front side of the wafer.

18. A throttle valve (TV) is disposed in the first pipe (A), A first valve (CHCV-1) is disposed near the vent (201) in the second pipeline (B); The third pipeline (C) is connected to the second pipeline (B) downstream of the first valve (CHCV-1), and a second valve (CHCV-2) is disposed in the third pipeline (C); The second pipe (B) branches into a first manifold pipe (B1) and a second manifold pipe (B2) downstream of the first valve (CHCV-1), the other end of the first manifold pipe (B1) is connected to the first pipe (A) between the extraction port (101) of the reaction chamber (100) and the throttle valve (TV), and a third valve (CHCV-3) is disposed in the first manifold pipe (B1); The method according to claim 13, wherein the other end of the second manifold line (B2) is connected to the vacuum pump (300), and a fourth valve (CHCV-4) is disposed in the second manifold line (B2).

19. The method according to claim 18, characterized in that, during the execution of step (a), the first valve (CHCV-1), the second valve (CHCV-2), the third valve (CHCV-3) and the fourth valve (CHCV-4) are all off, and the throttle valve (TV) is on.

20. 19. The method according to claim 18, characterized in that, during the execution of step (b), the first valve (CHCV-1), the second valve (CHCV-2) and the fourth valve (CHCV-4) are all on, and the third valve (CHCV-3) is off.

21. 21. The method according to claim 20, wherein in step (b), the flow rate of the gas in the third line (C) is adjusted so that the pressure on the back side of the wafer is 30 to 150 Torr lower than the pressure on the front side of the wafer.

22. 19. The method according to claim 18, characterized in that, during the execution of step (c), the first valve (CHCV-1), the second valve (CHCV-2) and the third valve (CHCV-3) are all on, and the fourth valve (CHCV-4) is off.

23. 23. The method according to claim 22, wherein in step (c), the flow rate of the gas in the third line (C) is adjusted so that the pressure on the backside of the wafer is higher than the pressure on the frontside.

24. 24. The method according to claim 23, wherein in step (c), the flow rate of the gas in the third line (C) is adjusted so that the pressure on the back side of the wafer is 5 to 10 Torr higher than the pressure on the front side of the wafer.

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