Device and method for adjusting film stress and process equipment of semiconductor device

Abstract

The invention discloses a thin film stress adjusting device and method and process equipment of a semiconductor device. The adjusting device comprises a heating disc on which a wafer coated with a film on the front side is placed at intervals, and the surface of the heating disc is provided with a plurality of air outlet areas corresponding to a plurality of areas on the back side of the wafer; the controller is configured to respond to a first deformation area which is warped due to the stress of a first thin film on the front side in the wafer and output reaction gas from the gas outlet area below the first deformation area so as to deposit a second thin film on the first deformation area on the back side of the wafer, the second thin film provides downward tensile stress for the first deformation area. According to the invention, the problem of deformation of the coated wafer caused by the stress of the front film can be improved in a targeted manner, and the stability of the product is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor manufacturing, and in particular to a device for adjusting film stress, a method for adjusting film stress, a process equipment for a semiconductor device, and a computer-readable storage medium. Background Art

[0002] In current semiconductor device process equipment, the thin film deposited by spraying reaction gas through a spray component, such as a shower head (SHD), is generally formed as a whole on the entire wafer area. As the thickness of the film on the wafer surface increases, the wafer will warp under the stress of the film, which will be detrimental to subsequent film deposition and subsequent applications. In addition, the uneven distribution of the reaction gas sprayed on the wafer surface will cause uneven distribution of the thin film material on the wafer, which may also cause the wafer to warp.

[0003] When the tensile stress and / or compressive stress on the front of the wafer reaches a certain level and cannot be released during the deposition process, the wafer is prone to serious warping or even fragmentation. In addition, for the product structure, when the film stress difference between different areas of the wafer is too large, it will lead to large structural differences in different areas of the wafer, which will also have an adverse effect on the stability of the product.

[0004] In order to solve the above problems existing in the prior art, the art urgently needs a thin film stress adjustment technology that can specifically improve the deformation problem of the coated wafer caused by the thin film stress on the front side and improve the stability of the product. Summary of the invention

[0005] A brief summary of one or more aspects is given below to provide a basic understanding of these aspects. This summary is not an exhaustive overview of all conceived aspects, and is neither intended to identify the key or decisive elements of all aspects nor to define the scope of any or all aspects. Its only purpose is to give some concepts of one or more aspects in a simplified form as a prelude to a more detailed description that will be given later.

[0006] In order to overcome the above-mentioned defects of the prior art, the present invention provides a device for adjusting thin film stress, a method for adjusting thin film stress, a process equipment for a semiconductor device, and a computer-readable storage medium, which can specifically improve the deformation problem of the coated wafer caused by the thin film stress on the front side and enhance the stability of the product.

[0007] Specifically, the above-mentioned thin film stress adjustment device provided according to the first aspect of the present invention includes: a heating plate, on which a wafer coated on the front side is placed in the air, and a plurality of gas outlet areas are provided on the surface of the heating plate to correspond to the plurality of areas on the back side of the wafer; and a controller, which is configured to: in response to the appearance of a first deformation zone in the wafer that is warped due to the first thin film stress on the front side, output a reaction gas from the gas outlet area below the first deformation zone to deposit a second thin film on the first deformation zone on the back side of the wafer, wherein the second thin film provides downward tensile stress to the first deformation zone.

[0008] Furthermore, in some embodiments of the present invention, the surface of the heating plate includes a central gas outlet area and two side gas outlet areas, and the controller is further configured to: in response to the deformation of the wafer with a central concave shape and warping on both sides, determine that the two side areas of the wafer are first deformation areas; and output reaction gas from the two side gas outlet areas to deposit the second film on the two side areas on the back side of the wafer.

[0009] Furthermore, in some embodiments of the present invention, the controller is further configured to: determine that the central area of ​​the wafer is a first deformation zone in response to the deformation of the wafer in which the center is warped and the two sides are concave; and output the reaction gas from the central gas outlet area to deposit the second film in the central area on the back side of the wafer.

[0010] Furthermore, in some embodiments of the present invention, the controller is further configured to: in response to irregular warping deformation of the wafer, determine that the entire surface of the wafer is a first deformation zone; and output reaction gas from the multiple gas outlet zones to deposit the second film on the entire back side of the wafer.

[0011] Furthermore, in some embodiments of the present invention, the step of outputting reaction gas from the gas outlet zone below the first deformation zone to deposit the second film in the first deformation zone on the back side of the wafer also includes: outputting an inert gas from the gas outlet zone below a second area of ​​the wafer where no warping has occurred, so that the inert gas forms a protective layer in the second area on the back side of the wafer, thereby limiting the deposition range of the second film.

[0012] Furthermore, in some embodiments of the present invention, the adjustment device also includes: a base, which includes a plurality of gas pipes inside, respectively used to introduce the reaction gas or the inert gas; and a flow distribution channel, which is arranged on the surface of the base, including at least two flow channels extending from the center of the surface of the base to the edge, wherein the starting end of the flow channel is connected to one of the gas pipes, and the terminal end thereof extends to the edge of the surface, so as to distribute the reaction gas or the inert gas in a first stage so that it flows to the edge.

[0013] Furthermore, in some embodiments of the present invention, the heating plate includes a diverter plate, which is arranged above the base, and the diverter plate includes a plurality of boundary areas, each of the boundary areas includes a different hole distribution, which is used to receive the reaction gas and the inert gas transmitted through the diverter channel, and perform secondary gas separation to separately transmit the reaction gas and the inert gas to different areas.

[0014] Furthermore, in some embodiments of the present invention, the diverter plate includes two centrally symmetrical air channels to divide the diverter plate into a central boundary area and two side boundary areas located on both sides thereof, and the central boundary area includes guide holes to allow the reaction gas and the inert gas to be separately transmitted through the air channels and the guide holes, respectively.

[0015] Furthermore, in some embodiments of the present invention, a first baffle is further provided between the flow channel terminal of the flow branch channel and the flow branch plate, for reducing the flow rate of the reaction gas or the inert gas flowing toward the boundary areas on both sides.

[0016] Furthermore, in some embodiments of the present invention, the heating plate also includes a perforated plate, which is arranged above the diverter plate, and the perforated plate is divided into three uniform gas zones through a partition channel, respectively corresponding to the central dividing zone and the two side dividing zones on both sides of the diverter plate, so as to output the reaction gas or inert gas output through the central dividing zone and the two side dividing zones in three levels, so that it is evenly distributed in multiple areas on the back side of the wafer.

[0017] Furthermore, in some embodiments of the present invention, a second baffle is further included between the central boundary area of ​​the diverter plate and the orifice plate to reduce the flow rate of the reaction gas or the inert gas flowing to the central uniform gas area of ​​the orifice plate.

[0018] In addition, the above-mentioned thin film stress adjustment method provided according to the second aspect of the present invention includes the following steps: obtaining the warping condition of the wafer coated on the front side; and in response to the appearance of a first deformation zone in the wafer that is warped due to the first thin film stress on the front side, outputting reaction gas from the gas outlet zone below the first deformation zone in the heating plate through the above-mentioned thin film stress adjustment device provided by the first aspect of the present invention, so as to deposit a second thin film in the first deformation zone on the back side of the wafer, and the first deformation zone recovers the deformation through the downward tensile stress provided by the second film.

[0019] Furthermore, in some embodiments of the present invention, the step of outputting reaction gas from the gas outlet zone below the first deformation zone in the heating plate to deposit a second thin film in the first deformation zone on the back side of the wafer includes: determining a target thickness of the second thin film according to a degree of warping of the wafer; determining a ventilation time of the reaction gas based on the target thickness, wherein the film thickness of the second thin film is proportional to the ventilation time of the reaction gas; and continuously introducing the reaction gas into the gas outlet zone below the first deformation zone according to the ventilation time to deposit a second thin film meeting the target thickness in the first deformation zone on the back side of the wafer.

[0020] Furthermore, in some embodiments of the present invention, the step of outputting the reaction gas from the gas outlet zone below the first deformation zone in the heating disk to deposit the second film in the first deformation zone on the back side of the wafer also includes: outputting the reaction gas from the gas outlet zone below the first deformation zone in the heating disk, and simultaneously outputting an inert gas from the gas outlet zone below a second area of ​​the wafer where no warping has occurred, so that the inert gas forms a protective layer in the second area to limit the deposition range of the second film.

[0021] In addition, the process equipment of the above-mentioned semiconductor device provided according to the third aspect of the present invention includes: a reaction chamber; and the above-mentioned thin film stress adjustment device provided by the first aspect of the present invention, which is located in the reaction chamber, and a wafer coated on the front side is placed in the air on the heating plate of the thin film stress adjustment device to restore the deformation of the first deformation area of ​​the wafer that is warped due to the first thin film stress on the front side.

[0022] In addition, according to the fourth aspect of the present invention, there is also provided a computer-readable storage medium on which computer instructions are stored. When the computer instructions are executed by a processor, the above-mentioned film stress adjustment method provided by the third aspect of the present invention is implemented. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The above features and advantages of the present invention can be better understood after reading the detailed description of the embodiments of the present disclosure in conjunction with the following drawings. In the drawings, the components are not necessarily drawn to scale, and components with similar related properties or features may have the same or similar reference numerals.

[0024] Figure 1 A schematic structural diagram of a device for adjusting film stress according to some embodiments of the present invention is shown;

[0025] Figure 2 An exploded view of a device for adjusting film stress according to some embodiments of the present invention is shown;

[0026] Figure 3 A schematic diagram showing the structure of a base surface provided according to some embodiments of the present invention is shown;

[0027] Figure 4A and 4B The structural schematic diagrams of two kinds of diverter plates provided according to some embodiments of the present invention are respectively shown;

[0028] Figure 5A , 5B 5C respectively show the structural schematic diagrams of three orifice plates provided according to some embodiments of the present invention;

[0029] Figure 6 A flow chart of a method for adjusting film stress according to some embodiments of the present invention is shown;

[0030] Figure 7 A schematic diagram showing an airflow distribution path of a device for adjusting film stress provided in some embodiments of the present invention; and

[0031] Figure 8 A schematic diagram showing the silane mass distribution on the back side when adjusting the film stress provided by some embodiments of the present invention; and

[0032] Fig. 9 A flow chart of depositing a second film on a first deformation region on the back side of a wafer according to some embodiments of the present invention is shown.

[0033] Reference numerals:

[0034] 100 Film stress adjustment device;

[0035] 110 heating plate;

[0036] 111 support seat;

[0037] 112 support frame;

[0038] 120 base;

[0039] 131 central outlet area;

[0040] 132, 133, air outlet areas on both sides;

[0041] 211 first trachea;

[0042] 212 Second trachea;

[0043] 220 Heating element;

[0044] 221 cover;

[0045] 230 first baffle;

[0046] 240 second baffle;

[0047] 300 points airflow channel;

[0048] 310 flow channel;

[0049] 311 The beginning of the flow channel;

[0050] 312 terminal end of flow channel;

[0051] 320 center vent;

[0052] 400, 400a, 400b manifold;

[0053] 410a, 410b air duct;

[0054] 411 Stomatal channel array;

[0055] 421 Central Dividing Area;

[0056] 422 The dividing area on both sides;

[0057] 430 diversion hole;

[0058] 500, 500a, 500b, 500c orifice plates;

[0059] 510a, 510b, 510c central uniform gas zone;

[0060] 520a, 520b, 520c are gas homogenizing areas on both sides;

[0061] 530a Partition passage;

[0062] Steps S610 to S630;

[0063] 710 First Gas;

[0064] 720 second gas; and

[0065] Steps S621~S623. DETAILED DESCRIPTION

[0067] The following specific embodiments illustrate the implementation of the present invention, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Although the description of the present invention will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this invention are limited to this implementation. On the contrary, the purpose of introducing the invention in conjunction with the implementation is to cover other options or modifications that may be extended based on the claims of the present invention. In order to provide a deep understanding of the present invention, the following description will include many specific details. The present invention can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present invention, some specific details will be omitted in the description.

[0068] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0069] In addition, the terms "upper", "lower", "left", "right", "top", "bottom", "horizontal" and "vertical" used in the following description should be understood as the directions shown in the paragraph and the related drawings. Such relative terms are only used for the convenience of description and do not mean that the device described therein must be manufactured or operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0070] It is understood that although the terms "first", "second", "third", etc. may be used herein to describe various components, regions, layers and / or parts, these components, regions, layers and / or parts should not be limited by these terms, and these terms are only used to distinguish different components, regions, layers and / or parts. Therefore, the first component, region, layer and / or part discussed below may be referred to as a second component, region, layer and / or part without departing from some embodiments of the present invention.

[0071] As mentioned above, in the current semiconductor device process equipment, the thin film deposited by spraying the reaction gas through a spray component, such as a shower head (SHD), is generally formed as a whole on the entire wafer area. As the thickness of the film on the wafer surface increases, the wafer will warp under the stress of the film, which will be detrimental to subsequent film deposition and subsequent applications. In addition, the uneven distribution of the reaction gas sprayed on the wafer surface will cause uneven distribution of the thin film material on the wafer, which may also cause the wafer to warp.

[0072] In order to solve the above-mentioned problems existing in the prior art, the present invention provides a device for adjusting thin film stress, a method for adjusting thin film stress, a process equipment for a semiconductor device, and a computer-readable storage medium, which can specifically improve the deformation problem of the coated wafer caused by the thin film stress on the front side and enhance the stability of the product.

[0073] In some non-limiting embodiments, the above-mentioned film stress adjustment device provided by the first aspect of the present invention can be configured in the process equipment of the above-mentioned semiconductor device provided by the third aspect of the present invention, and used to implement the above-mentioned film stress adjustment method provided by the second aspect of the present invention.

[0074] Specifically, in some non-limiting embodiments, the computer-readable storage medium provided in the fourth aspect of the present invention stores computer instructions, which, when executed by a processor, can be used to implement the film stress adjustment method provided in the second aspect of the present invention.

[0075] The working principle of the above-mentioned thin film stress adjustment device will be described below in conjunction with some embodiments of process equipment of semiconductor devices and methods for adjusting thin film stress. Those skilled in the art will understand that the embodiments of process equipment of these semiconductor devices and methods for adjusting thin film stress are only some non-limiting implementation methods provided by the present invention, which are intended to clearly demonstrate the main concept of the present invention and provide some specific solutions that are convenient for the public to implement, rather than to limit all working modes or all functions of the thin film stress adjustment device. Similarly, the thin film stress adjustment device is also only a non-limiting implementation method provided by the present invention, and does not constitute a limitation on other configuration objects in the process equipment of these semiconductor devices, and the implementation subjects of each step in the method for adjusting thin film stress.

[0076] Specifically, in some embodiments of the present invention, the process equipment of the semiconductor device may include a reaction chamber, the interior of which is used for performing a process reaction. A thin film stress adjustment device may be included inside the reaction chamber. A wafer coated on the front side may be placed in the air on the heating plate of the thin film stress adjustment device to restore the deformation of the first deformation area of ​​the wafer that is warped due to the first thin film stress on the front side.

[0077] For this, see Figure 1 , Figure 1 A schematic structural diagram of a device for adjusting film stress provided according to some embodiments of the present invention is shown.

[0078] like Figure 1As shown, in some embodiments of the present invention, the device 100 for adjusting film stress may include a heating plate 110 and a controller (not shown in the drawings). The front-coated wafer 70 may be placed in the air on the heating plate 110, and the surface of the heating plate 110 may be provided with multiple gas outlet areas, for example, a central gas outlet area 131 and two side gas outlet areas 132 and 133 located on both sides thereof, respectively corresponding to multiple areas on the back of the wafer 70. The controller may be configured to: in response to the first deformation zone in the wafer 70 that is warped due to the first film stress on the front side, output the reaction gas from the gas outlet area below the first deformation zone to deposit the second film on the first deformation zone on the back of the wafer, wherein the second film can provide downward tensile stress to the first deformation zone. That is to say, according to the requirements, the present embodiment can form a film on the back of the wafer 70 in a partitioned manner, so that different stress-strain effects can be generated by controlling the different film thicknesses on the back of the wafer 70 to adjust the warping deformation of the wafer 70.

[0079] Specifically, in some optional embodiments, a plurality of horseshoe-shaped support seats 111 may be provided on the edge of the heating plate 110, and a ceramic annular support frame 112 may be provided on the upper end of the plurality of support seats 111. Through the cooperation of the support seats 111 and the support frame 112, a support may be provided for the wafer 70, so that the wafer 70 is fixed above the heating plate 110 in the air. Preferably, in order to facilitate the flow and diffusion of the reaction gas on the back side of the wafer 70, the air distance between the back side of the wafer 70 and the heating plate 110 may be 5 to 15 mm.

[0080] Furthermore, if Figure 1 As shown, in some embodiments, the film stress adjustment device 100 may further include a base 120 to support the heating plate 110. Figure 2 , Figure 2 An exploded view of a device for adjusting film stress provided according to some embodiments of the present invention is shown.

[0081] like Figure 2 As shown, in some embodiments, the heating plate 110 may include a heating element 220 , wherein the heating element 220 may include a resistance wire or a liquid heating pipeline, such as an oil heating pipeline. The heating element 220 may be installed in the heating plate 110 through a cover plate 221 .

[0082] like Figure 2 As shown, the interior of the base 120 may also include a plurality of gas pipes, which may be used to introduce reaction gas and inert gas, respectively. For example, the first gas pipe 211 may be used to introduce reaction gas, and the second gas pipe 212 may be used to introduce inert gas. It is understood that the types of gases introduced into the first gas pipe 211 and the second gas pipe 212 may be interchanged according to actual process requirements, or both gas pipes may be introduced with reaction gas.

[0083] Since the partitioned film formation may lead to uneven gas distribution during gas discharge, this will not only lead to uneven distribution of the film material on the wafer, causing the wafer to warp and deform, but also the uneven gas discharge method may cause the gas to be sprayed onto the wafer surface, leaving spray marks on the wafer surface, thus directly affecting the quality of the film. In this regard, the present invention also provides a three-stage split gas discharge method, which can achieve uniform distribution of the sprayed gas on the target area on the back of the wafer 70.

[0084] Specifically, see Figure 3 , Figure 3 A schematic structural diagram of a base surface provided according to some embodiments of the present invention is shown.

[0085] like Figure 3 As shown, in some embodiments of the present invention, a flow channel 300 may be provided on the surface of the base 120. The flow channel 300 may include at least two channels 310 extending from the center to the edge of the surface of the base 120 to perform a primary gas separation on the reaction gas and the inert gas so that they are transmitted separately.

[0086] Optionally, the starting end 311 of the flow channel can be connected to a gas pipe, and the terminal end 312 of the flow channel can extend to the edge of the surface of the base 120, so that the reaction gas or inert gas flows toward the edge of the surface, while the inert gas or reaction gas in another gas pipe is transmitted from the center of the surface.

[0087] For example, if Figure 3 As shown, the center of the surface of the base 120 may include a central gas outlet 320, which may be connected to the first gas pipe 211, and the inert gas is output from the central gas outlet area 131 of the heating plate 110 through the central gas outlet 320. The second gas pipe 212 may be connected to the flow channel 300. The reaction gas provided by the second gas pipe 212 may be divided into two from the beginning 311 of the flow channel through the flow channel 300, and divided into two paths to flow to the edge of the base 120, so as to output the reaction gas from the two side gas outlet areas 132 and 133 of the heating plate 110, thereby completing the primary gas separation of the reaction gas and the inert gas on the surface of the base 120.

[0088] Please continue to return Figure 2 In some embodiments of the present invention, the heating plate 110 may include a manifold 400, and the manifold 400 may be disposed above the base 120. The manifold 400 may include a plurality of boundary areas, and each boundary area may include a different hole distribution, which may be used to receive the reaction gas and the inert gas transmitted through the flow channel 300, and perform secondary gas separation, so as to separate the gas paths to different areas. By separating the transmission of the reaction gas and the inert gas, it is beneficial to perform the subsequent partitioned film formation on the back side of the wafer 70.

[0089] Specifically, see Figure 4A and 4B , Figure 4A and 4B The structural schematic diagrams of two kinds of diverter plates provided according to some embodiments of the present invention are respectively shown.

[0090] Alternatively, if Figure 4A As shown, in some embodiments, the manifold 400a may include two centrally symmetrical gas channels 410a, and the manifold 400a may be divided into a central boundary area 421 and two side boundary areas 422 located on both sides thereof through the two gas channels 410a, and the central boundary area 421 may include a guide hole 430. Through the guide hole 430 in the central boundary area 421 and the gas channels 410a and 410b located in the two side boundary areas 422, the reaction gas and the inert gas may be separately transmitted through the guide hole 430 and the gas channels 420a and 410b, respectively.

[0091] Alternatively, if Figure 4B As shown, in other embodiments, the boundary areas 422 on both sides of the manifold 400b may also include multiple air channels 410b to form an air channel array 411 to improve the uniformity of the reaction gas or inert gas passing through the boundary areas 422 on both sides during the transmission process.

[0092] Furthermore, continue as Figure 2 As shown, in some optional embodiments, a first baffle 230 may be further included between the terminal 312 of the flow channel of the flow channel 300 of the base 120 and the flow divider plate 400. The first baffle 230 may be used to reduce the flow rate of the reaction gas or inert gas flowing to the boundary areas 422 on both sides, which is conducive to uniform gas output.

[0093] Continue as Figure 2 As shown, in some embodiments of the present invention, the heating plate 110 may further include a perforated plate 500. The perforated plate 500 may be disposed above the diverter plate 400. For details, please refer to Figure 5A , 5B , 5C, Figure 5A , 5B 5C respectively show the structural schematic diagrams of three orifice plates provided according to some embodiments of the present invention.

[0094] by Figure 5AFor example, the orifice plate 500a can be divided into three uniform gas zones through the partition channel 530a, which respectively correspond to the positions of the central dividing area 421 and the two side dividing areas 422 on both sides of the diverter plate 400, and are used to perform three-level gas distribution output on the reaction gas and inert gas output through the central dividing area 421 and the two side dividing areas 422, so that they are evenly distributed in multiple areas on the back side of the wafer 70.

[0095] Alternatively, if Figure 5A As shown, in some embodiments, the shapes of the central gas homogenizing area 510a and the gas homogenizing areas 520a on both sides of the orifice plate 500a may be the same as the shapes of the central boundary area 421 and the gas homogenizing areas 520 on both sides of the diverter plate 400. For example, Figure 5A The orifice plate 500a in Figure 4B The middle flow dividing plate 400b cooperates to perform secondary gas distribution and tertiary gas distribution.

[0096] like Figure 5B and Figure 5C As shown, in some other optional embodiments, the shapes of the central uniform gas area 510b, 510c and the two side uniform gas areas 520b, 520c in the orifice plates 500b, 500c may also be different from the shapes of the central boundary area 421 and the two side uniform gas areas 520 in the splitter plate 400. For example, Figure 5B The middle hole plate 500b can be Figure 4A or the splitter plates 400a or 400b in 4B cooperate to perform secondary gas splitting and tertiary gas splitting, and Figure 5C The orifice plate 500c in the Figure 4A The splitter plates 400a or 400b in or 4B are combined to perform secondary gas separation and tertiary gas separation.

[0097] Those skilled in the art can understand that the above-mentioned division of the shape, area, and number of the boundary areas in the manifold 400, and the division of the shape, area, and number of the uniform gas areas in the orifice plate 500, are only a non-limiting implementation scheme provided by the present invention, which is intended to clearly demonstrate the main concept of the present invention and provide a specific scheme that is convenient for the public to implement, rather than to limit the scope of protection of the present invention. Optionally, in other embodiments, those skilled in the art can also divide the manifold 400 and the orifice plate 500 into a corresponding number of boundary areas and uniform gas areas based on the concept of the present invention, and the shapes and areas of the boundary areas and the uniform gas areas do not need to be equal, as long as the number is the same and the positions correspond.

[0098] Further, continue back to Figure 2In some optional embodiments, a second baffle 240 may be further included between the central boundary area 421 of the manifold 400 and the orifice plate 500. The second baffle 240 may be used to reduce the flow rate of the reaction gas or the inert gas flowing to the central uniform gas area 510 of the orifice plate 500.

[0099] like Figure 2 As shown, the assembly method of the components in the device 100 for adjusting film stress may include the following process. First, the first baffle 230 may be connected to the base 120 by a threaded connection, and then the second baffle 240 may be bolted to the diverter plate 400. Afterwards, the orifice plate 500 and the diverter plate 400 in the heating disk 110 may be threadedly connected to the base 120 of the heating disk body and pre-tightened by a certain pressure. After the heating element 220 (such as a resistance wire) is installed, the heating element 220 may be fixed by welding the cover plate 221. Finally, the entire device 100 for adjusting film stress may be installed in the process equipment of the semiconductor device. Optionally, after mass production is achieved in the later stage, welding methods such as vacuum brazing / EBW may be used instead of threaded connection.

[0100] Since the reaction gas sprayed onto the surface of the wafer is unevenly distributed, the thin film material on the wafer will be unevenly distributed, and the wafer may also be warped. Partitioned film formation may lead to uneven gas distribution during gas outlet, or even spray marks on the wafer surface. Therefore, in the above-mentioned embodiment of the present invention, by adopting a three-stage gas distribution method, the uniformity of the reaction gas output from the surface of the heating disk 110 can be greatly improved, so that the thin film material on the first deformation zone on the back of the wafer 70 is evenly distributed, and a uniform second thin film can be generated, providing uniform downward tensile stress to the first deformation zone. At the same time, the problem of gas injection marks on the wafer surface can be improved to obtain a high-quality film.

[0101] Specifically, according to the combination of the diverter plate 400 and the orifice plate 500, it is possible to realize the film formation in different regions on the back of the wafer, and the thickness of the film formed in each region can be controlled, and different types of films can also be deposited. For example, by controlling the gas of the first air pipe 211 and the second air pipe 212, and combining the change of the radio frequency energy, the second film can provide the required tensile stress / compressive stress on the back of the wafer, so that the wafer can recover the deformation similar to the saddle surface. In addition, the three-stage gas distribution method is adopted, and the small baffles (the first baffle 230 and the second baffle 240) are added, which can effectively improve the problem of spray marks on the surface of the wafer caused by gas injection.

[0102] In terms of the shape of the partitioned film, by adopting the assembled structure of baffles, diverter plates and orifice plates, different baffles, diverter plates ( Figure 4A and 4B The splitter plate 400a and splitter plate 400b) and the orifice plate ( Figure 5A , orifice plates 500a, 500b, 500c in 5B and 5C), thereby realizing various partitioned thin film deposition schemes, while facilitating subsequent continuous improvement plans (Continuous Improvement Process, CIP) and reducing subsequent design iteration time.

[0103] Considering the diffusion of gas and the distance between the heating plate 110 and the back of the wafer, different orifice plates 500 and diverter plates 400 can be designed to cooperate with each other, hoping to achieve the same effect, that is, the thin film deposited in the central area of ​​the back of the wafer can have a clear boundary with the thin film deposited in the two side areas. The thin film stress adjustment device 100 of the present invention can be used to perform partitioned film formation on the back of the wafer according to process requirements, thereby specifically improving the problem of wafer warping deformation.

[0104] Next, the working principle of the above-mentioned film stress adjustment device 100 will be further described in combination with the film stress adjustment method. Figure 6 , Figure 6 A flow chart of a method for adjusting film stress provided according to some embodiments of the present invention is shown.

[0105] like Figure 6 As shown, in some embodiments of the present invention, before the film stress adjustment process is performed, the temperature of the process environment in the reaction chamber can be adjusted to 200-500° C., and the pressure in the reaction chamber can be adjusted to 1-10 torr, preferably less than 5 torr, and then the temperature of the resistance wire in the heating plate 110 can be adjusted to 300-450° C. The film stress adjustment method can include the following steps.

[0106] First, step S610 may be performed: obtaining the warpage of the wafer with the front side coated.

[0107] In some optional embodiments, after the deposition of the first thin film is completed on the front side of the wafer in the reaction chamber, the warping condition of the wafer coated on the front side can be obtained by a detection device.

[0108] Afterwards, step S620 can be executed: in response to the first deformation zone that warps in the wafer due to the first film stress on the front side, a reaction gas is output from the gas outlet area below the first deformation zone in the heating plate via a film stress adjustment device to deposit a second film on the first deformation zone on the back side of the wafer, and the first deformation zone recovers its deformation due to the downward tensile stress provided by the second film.

[0109] Specifically, it can be combined Figure 2 and Figure 7 Common understanding, Figure 7A schematic diagram of the airflow distribution path of a device for adjusting film stress according to some embodiments of the present invention is shown.

[0110] like Figure 2 and Figure 7 As shown, in some optional embodiments, the surface of the heating plate 110 may include a central gas outlet area 131 and two side gas outlet areas 132 and 133 located on both sides thereof. When the deformation of the wafer 70 with a concave center and warping on both sides is detected, the two side areas of the wafer 70 can be determined as the first deformation area. The controller can control the output of the reaction gas from the two side gas outlet areas 132 and 133 of the heating plate 110 to deposit the second film on the two side areas of the back of the wafer 70. The uniform downward tensile stress provided by the second film can reduce the warping degree of the two side areas of the wafer to restore its deformation.

[0111] Optionally, silane may be used as the reaction gas to deposit a silicon-containing film such as silicon nitride or silicon oxide as the second film.

[0112] Furthermore, if Figure 7 As shown, in some preferred embodiments, when the reaction gas is introduced into the two side gas outlet areas 132 and 133 in the heating disk 110 through the first gas pipe 211 in the film stress adjustment device 100, the inert gas can be introduced into the central gas outlet area 131 in the heating disk 110 through the second gas pipe 212 at the same time. Since the upper part of the central gas outlet area 131 in the heating disk 110 corresponds to the second area where the wafer 70 does not undergo warping deformation, a protective layer can be formed below the second area by outputting the inert gas below the second area to prevent the reaction gas from diffusing to the second area on the back of the wafer 70 and forming a film in the second area. In this embodiment, the distribution area of ​​the reaction gas can be accurately controlled by introducing the reaction gas and the inert gas at the same time, thereby limiting the deposition range of the second film.

[0113] Specifically, Figure 7As shown, the heating plate 110 in the device 100 for adjusting film stress, and the orifice plate 500, the first baffle plate 230, the second baffle plate 240, and the diverter plate 400 therein are generally made of aluminum alloy. The first gas 710 may be an inert gas, and the second gas 720 may be a reactive gas. The first gas 710 and the second gas 720 may enter the heating plate 110 from different gas paths inside the base 120, respectively. The first gas 710 enters the central gas outlet 320 on the surface of the base 120 from the first gas pipe 211 of the base 120, and then directly enters the heating plate 110. Then, the first gas 710 passes through the guide hole 430 of the diverter plate 400, and after the flow rate is reduced by the second baffle plate 240, it reaches the second area on the back of the wafer 70 from the central uniform gas area 510 of the orifice plate 500. The second gas 720 enters the flow channel 300 on the surface of the base 120 from the second gas pipe 212 of the base 120, and after the first-level gas separation in the flow channel 300, it is divided into two and flows to the two side edges of the base 120. Then, the second gas 720 enters the flow divider plate 400 after the flow rate is reduced by the second baffle 240. The second gas 720 is subjected to the second-level gas separation in the flow divider plate 400, and is uniformly output to the orifice plate 500 through the multiple gas channels 410 in the boundary areas 422 on both sides, and then is subjected to the third-level gas separation through the orifice plate 500, and flows from the uniform gas areas 520 on both sides of the orifice plate 500 to the first deformation area on the back of the wafer 70.

[0114] For further information, see Figure 8 , Figure 8 A schematic diagram of silane mass distribution on the back side during adjustment of film stress according to some embodiments of the present invention is shown.

[0115] like Figure 8 As shown in the second figure in FIG, the A region on the back of the wafer 70 is the first deformation zone, corresponding to the central gas outlet zone 131 on the surface of the heating plate 110, and the B region and the C region are the second region, corresponding to the gas outlet zones 132 and 133 on both sides of the surface of the heating plate 110. The reaction gas silane can be distributed in the B region and the C region on the back of the wafer 70, and the inert gas nitrogen can be distributed in the A region on the back of the wafer 70. Optionally, when the wafer 70 is 300 mm in diameter, the range of the A region can reach 150 mm.

[0116] In some other optional embodiments, when the deformation of the wafer 70 with warping in the center and concave on both sides is detected, the central area of ​​the wafer 70 can be determined as the first deformation area. The controller can control the output of the reaction gas from the central gas outlet area 131 of the heating plate 110 to deposit the second thin film in the central area on the back of the wafer 70. At the same time, the controller can also control the output of the inert gas from the gas outlet areas 132 and 133 on both sides of the heating plate 110 to form a protective layer under the two side areas of the wafer 70 where no warping deformation occurs, so as to prevent the reaction gas from diffusing to the second area on the back of the wafer 70 and forming a film in the second area. Figure 7 As shown, at this time, the first gas 710 can be a reactive gas, and the second gas 720 can be an inert gas. The specific gas flow distribution paths of the first gas 710 and the second gas 720 have been described in detail above and will not be repeated here. The uniform downward tensile stress provided by the second film can reduce the warpage of the center of both sides of the wafer and restore its deformation.

[0117] like Figure 8 As shown in the first figure, the A region on the back of the wafer 70 is the second region, corresponding to the central gas outlet area 131 on the surface of the heating plate 110, and the B region and the C region are the first deformation region, corresponding to the gas outlet areas 132 and 133 on both sides of the surface of the heating plate 110. The reaction gas silane can be distributed in the A region on the back of the wafer 70, and the inert gas nitrogen can be distributed in the B region and the C region on the back of the wafer 70. Optionally, when the wafer 70 is 300 mm in diameter, the range of the A region can reach 150 mm.

[0118] exist Figure 7 In the illustrated embodiment, although the first gas 710 and the second gas 720 enter the heating plate 110 at the same time, due to the flow distribution channel 300 in the base 120 and the partition channel 530 in the orifice plate 500, the two gases can be clearly separated, making it difficult for them to mix during the transmission process, and thus they will not diffuse and fuse when they finally reach the back side of the wafer 70.

[0119] Furthermore, in other embodiments, when irregular warping deformation of the wafer 70 is detected, the entire surface of the wafer 70 can be determined as the first deformation zone. At this time, the first gas pipe 211 and the second gas pipe 212 in the base 120 are both fed with reactive gas, such as silane. Then, the controller can control the multiple gas outlet areas of the heating plate 110 to output reactive gas, so as to deposit the second film on the entire back side of the wafer 70.

[0120] Preferably, according to the first embodiment of outputting inert gas in the central gas outlet area 131 of the heating disk 110 and outputting reaction gas in the gas outlet areas 132 and 133 on both sides, the second embodiment of outputting reaction gas in the central gas outlet area 131 of the heating disk 110 and outputting inert gas in the gas outlet areas 132 and 133 on both sides, and the third embodiment of outputting reaction gas in both the central gas outlet area 131 and the gas outlet areas 132 and 133 on both sides of the heating disk 110, these three combinations can be matched and superimposed in different orders, so as to further control the film thickness on the back side of the wafer accurately and produce different stress-strain effects. In the present invention, the thickness and uniformity of thin film deposition in different regions can be controlled through appropriate partition structures.

[0121] Furthermore, if Fig. 9 As shown, in some preferred embodiments, the above step S620 may further include steps S621 to S623.

[0122] Specifically, step S621 can be performed, and the controller can determine the target thickness of the second film according to the degree of warping of the wafer 70. Then, step S622 can be performed, and the controller can determine the ventilation time of the reaction gas based on the target thickness, wherein the film thickness of the second film is proportional to the ventilation time of the reaction gas. Afterwards, the controller can continuously introduce the reaction gas into the outlet area of ​​the heating plate 110 below the first deformation area of ​​the wafer 70 according to the ventilation time, so as to deposit a second film meeting the target thickness on the first deformation area on the back of the wafer.

[0123] Although the above methods are illustrated and described as a series of actions for simplicity of explanation, it should be understood and appreciated that these methods are not limited by the order of the actions, because according to one or more embodiments, some actions may occur in a different order and / or concurrently with other actions from those illustrated and described herein or not illustrated and described herein but understandable to those skilled in the art.

[0124] Those skilled in the art will further appreciate that the steps of the methods or algorithms described in conjunction with the embodiments disclosed herein may be directly embodied in hardware, in a software module executed by a processor, or in a combination of the two. The software module may reside in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to a processor so that the processor can read and write information from / to the storage medium. In an alternative, a storage medium may be integrated into a processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user terminal. In an alternative, the processor and the storage medium may reside in a user terminal as discrete components.

[0125] In one or more exemplary embodiments, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented as a computer program product in software, each function may be stored on or transmitted by a computer-readable medium as one or more instructions or codes. Computer-readable media include both computer storage media and communication media, including any medium that facilitates the transfer of a computer program from one place to another. Storage media may be any available medium that can be accessed by a computer. As an example and not limitation, such a computer-readable medium may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, disk storage or other magnetic storage device, or any other medium that can be used to carry or store the desired program code in the form of an instruction or data structure and can be accessed by a computer. Any connection is also properly referred to as a computer-readable medium. For example, if the software is transmitted from a website, a server, or other remote source using a coaxial cable, a fiber optic cable, a twisted pair, a digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwaves, the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwaves are included in the definition of the medium. Disk and disc as used herein include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray disc, wherein disk often reproduces data magnetically, while disc reproduces data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

[0126] In summary, the present invention provides a device for adjusting thin film stress, a method for adjusting thin film stress, a process equipment for a semiconductor device, and a computer-readable storage medium, which can specifically improve the deformation problem of coated wafers caused by the thin film stress on the front side and enhance the stability of the product.

[0127] The previous description of the disclosure is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other variations without departing from the spirit or scope of the disclosure. Thus, the disclosure is not intended to be limited to the examples and designs described herein, but should be granted the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A device for adjusting film stress, characterized in that: include: A heating plate, on which the wafer coated on the front side is placed in the air, and a plurality of gas outlet areas are provided on the surface of the heating plate to correspond to the plurality of areas on the back side of the wafer; as well as A controller is configured to: in response to the first deformation zone in the wafer being warped due to the first film stress on the front side, output a reaction gas from the gas outlet zone below the first deformation zone to deposit a second film in the first deformation zone on the back side of the wafer, wherein the second film provides downward tensile stress to the first deformation zone.

2. The adjustment device according to claim 1, characterized in that The surface of the heating plate includes a central air outlet area and two side air outlet areas, and the controller is further configured as follows: In response to the wafer being deformed such that the center is concave and the two sides are warped, determining the two side regions of the wafer as first deformation areas; and The reaction gas is output from the gas outlet areas on both sides to deposit the second film on the two side areas of the back side of the wafer.

3. The adjustment device according to claim 2, characterized in that The controller is further configured to: In response to the wafer being deformed in such a way that the center is warped and the two sides are concave, determining a central area of ​​the wafer as a first deformation area; and The reaction gas is output from the central gas outlet area to deposit the second film on the central area of ​​the back side of the wafer.

4. The adjusting device according to claim 2 or 3, characterized in that: The controller is further configured to: In response to the wafer exhibiting an irregular warping deformation, determining the entire surface of the wafer as a first deformation area; and The reaction gas is outputted from the plurality of gas outlet areas to deposit the second film on the entire back side of the wafer.

5. The adjustment device according to claim 1, characterized in that: The step of outputting the reaction gas from the gas outlet region below the first deformation region to deposit a second film on the first deformation region on the back side of the wafer further includes: An inert gas is output from a gas outlet area below a second area of ​​the wafer where no warping occurs, so that the inert gas forms a protective layer in the second area on the back side of the wafer to limit the deposition range of the second film.

6. The adjustment device according to claim 5, characterized in that Also includes: A base, comprising a first gas pipe and a second gas pipe, wherein the first gas pipe is used to introduce the reaction gas, and the second gas pipe is used to introduce the inert gas; as well as The flow distribution channels are arranged on the surface of the base, and include at least two flow channels extending from the center of the surface of the base to the edge, wherein the starting end of the flow channel is connected to one of the gas pipes, and the terminal end thereof extends to the edge of the surface, so that the reaction gas or the inert gas flows toward the edge, and the inert gas or the reaction gas in the other gas pipe is transmitted from the center of the surface, thereby completing the primary gas distribution of the reaction gas and the inert gas.

7. The adjustment device according to claim 6, characterized in that The heating plate includes a diverter plate, and the diverter plate includes multiple dividing areas. Each of the dividing areas includes a different hole distribution for receiving the reaction gas and the inert gas transmitted through the diverter flow channel, and performing secondary gas separation to separately transmit the reaction gas and the inert gas to different areas.

8. The adjustment device according to claim 7, characterized in that The manifold includes two centrally symmetrical air channels to divide the manifold into a central boundary area and two side boundary areas located on both sides thereof, and the central boundary area includes guide holes to allow the reaction gas and the inert gas to be separately transmitted through the air channels and the guide holes respectively.

9. The adjustment device according to claim 8, characterized in that A first baffle is also included between the flow channel terminal of the split flow channel and the splitter plate, which is used to reduce the flow rate of the reaction gas or the inert gas flowing to the boundary areas on both sides.

10. The adjustment device according to claim 8, characterized in that The heating plate also includes a perforated plate, which is arranged above the diverter plate. The perforated plate is divided into three uniform gas zones through a partition channel, respectively corresponding to the central boundary zone and the two side boundary zones on both sides of the diverter plate, so as to perform three-stage gas separation on the reaction gas and the inert gas output through the central boundary zone and the two side boundary zones, so that they are evenly output to multiple areas on the back side of the wafer.

11. The adjustment device according to claim 10, characterized in that A second baffle is also included between the central boundary area of ​​the splitter plate and the orifice plate, for reducing the flow rate of the reaction gas or the inert gas flowing to the central gas homogenizing area of ​​the orifice plate.

12. A method for adjusting film stress, characterized in that: The following steps are involved: Obtain the warpage of the wafer with front coating; as well as In response to the appearance of a first deformation zone in the wafer that is warped due to the first film stress on the front side, a reaction gas is output from a gas outlet area located below the first deformation zone in a heating plate via a film stress adjustment device as described in any one of claims 1 to 11, so as to deposit a second film in the first deformation zone on the back side of the wafer, and the first deformation zone recovers its deformation via the downward tensile stress provided by the second film.

13. The adjustment method according to claim 12, characterized in that: The step of outputting the reaction gas from the gas outlet area below the first deformation area of ​​the heating plate to deposit a second film on the first deformation area on the back side of the wafer comprises: determining a target thickness of the second film according to a warpage degree of the wafer; Based on the target thickness, determining the ventilation time of the reaction gas, wherein the film thickness of the second thin film is proportional to the ventilation time of the reaction gas; and The reaction gas is continuously introduced into the gas outlet area below the first deformation area according to the ventilation time, so as to deposit a second film meeting the target thickness in the first deformation area on the back side of the wafer.

14. The adjustment method according to claim 12, characterized in that: The step of outputting the reaction gas from the gas outlet area below the first deformation area of ​​the heating plate to deposit a second film on the first deformation area on the back side of the wafer also includes: The reaction gas is output from the outlet zone below the first deformation zone in the heating plate, and the inert gas is output from the outlet zone below the second area of ​​the wafer where no warping occurs, so that the inert gas forms a protective layer in the second area to limit the deposition range of the second film.

15. A process equipment for a semiconductor device, characterized in that: include: Reaction chamber; as well as The thin film stress adjustment device as described in any one of claims 1 to 11 is located in the reaction chamber, and a wafer coated on the front side is placed in the air on the heating plate of the adjustment device to restore the deformation of the first deformation area of ​​the wafer that is warped due to the first thin film stress on the front side.

16. A computer-readable storage medium having computer instructions stored thereon, characterized in that: When the computer instructions are executed by a processor, the method for adjusting thin film stress according to any one of claims 12 to 14 is implemented.

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