CN117373985A - Wafer carrying device, control method thereof and etching machine - Google Patents

Abstract

The embodiment of the disclosure discloses a wafer carrying device, comprising: the wafer bearing table is provided with a first surface and a second surface which are oppositely arranged, and the first surface is used for bearing a wafer; a plurality of ejector pins contacting the wafer and displaced along a first direction perpendicular to the first surface; a plurality of back pressure chambers located on one side of the second surface of the wafer carrier; a plurality of pressure sensors in one-to-one communication with the plurality of back pressure chambers; a plurality of nozzles correspondingly communicated with the plurality of back pressure chambers; the plurality of nozzles are positioned at adjacent positions of the ejector rods corresponding to the nozzles, and the horizontal heights of the outlet ends of the plurality of nozzles are equal; the control module is used for controlling the plurality of ejector rods to move away from the first surface so as to enable the wafer to be away from the first surface, and the horizontal height of the outlet ends of the plurality of nozzles is lower than that of the contact ends of the plurality of ejector rods and the wafer; and controlling the plurality of nozzles to jet air towards the surface of the wafer, and controlling a plurality of first distances of the plurality of ejector rods protruding out of the first surface according to the numerical value fed back by the plurality of pressure sensors so as to enable the wafer to be horizontal.

Description

Wafer carrying device, control method thereof and etching machine

Technical Field

The embodiment of the disclosure relates to the technical field of semiconductors, in particular to a wafer carrying device, a control method thereof and an etching machine.

Background

In some semiconductor fabrication tools, such as etching tools or gas deposition tools, wafer carriers are typically integrated or assembled to hold and carry wafers for different processes. The wafer carrier may also be used to hold the wafer during process flow or transfer of the wafer. As the semiconductor manufacturing process becomes finer and more stringent, the process requirements on the wafer carrier are also higher and higher, and there is room for improvement in the current wafer carrier.

Disclosure of Invention

In view of the above, embodiments of the present disclosure provide a wafer carrier apparatus, a control method thereof, and an etching machine.

According to aspects of embodiments of the present disclosure, there is provided a wafer carrier apparatus, including:

the wafer bearing table is provided with a first surface and a second surface which are oppositely arranged, and the first surface is used for bearing a wafer;

a plurality of ejector pins contacting the wafer and being displaced in a first direction perpendicular to the first surface;

a plurality of back pressure chambers located on one side of the second surface of the wafer carrier; a plurality of pressure sensors in one-to-one communication with the plurality of back pressure chambers;

A plurality of nozzles in one-to-one correspondence with the plurality of back pressure chambers; the nozzles are positioned at adjacent positions of the ejector rods corresponding to the nozzles, and the horizontal heights of the outlet ends of the nozzles are equal;

the control module is used for controlling the displacement of the plurality of ejector rods away from the first surface to enable the wafer to be away from the first surface, and the horizontal height of the outlet ends of the plurality of nozzles is lower than that of the contact ends of the plurality of ejector rods and the wafer; and controlling a plurality of nozzles to jet air towards the surface of the wafer, and controlling a plurality of first distances of the ejector rods protruding out of the first surface according to the numerical values fed back by the pressure sensors.

In some embodiments, the control module is configured to determine the first distance, and when the first distance is within a first preset range, control at least one ejector rod to displace along the first direction, and adjust the first distance.

In some embodiments, the value of the pressure sensor has a monotonic correspondence with the first distance when the first distance is within the first preset range.

In some embodiments, the outlet ends of the plurality of nozzles are flush with the first surface of the wafer carrier.

In some embodiments, the back pressure chamber includes a gas source port, a gas injection port, and a test port;

the air source port is used for being externally connected with an air source, and the air jet port is used for being communicated with the corresponding nozzle;

the test port is used for communicating the corresponding pressure sensor.

In some embodiments, the test port is located on an inner wall of the side opposite the gas jet port; the air source port is positioned on the inner wall of one side adjacent to the test port.

In some embodiments, the wafer carrier includes at least 3 of the lift pins.

According to some aspects of embodiments of the present disclosure, an etching machine is provided, including the wafer carrier described above, where the wafer carrier is located in the etching chamber.

In some embodiments, the etching station further comprises:

a level measurement device positioned in the etching cavity and used for measuring the first distance; when the first distance is in a first preset range, controlling at least one ejector rod to displace along the first direction, and adjusting the first distance.

According to some aspects of the embodiments of the present disclosure, there is provided a method for controlling a wafer carrier, including:

placing a wafer on a first surface of a wafer carrying table;

Displacing the plurality of ejector rods along a first direction perpendicular to the first surface and away from the first surface, so that the wafer is away from the first surface, and the level of the outlet ends of the plurality of nozzles is lower than the level of the contact ends of the plurality of ejector rods and the wafer; the plurality of nozzles are communicated with the plurality of back pressure chambers in a one-to-one correspondence manner, the plurality of nozzles are positioned at adjacent positions of the ejector rods corresponding to the plurality of nozzles, and the horizontal heights of the outlet ends of the plurality of nozzles are equal;

causing the plurality of nozzles to jet air toward the wafer surface; and controlling a plurality of first distances of the plurality of ejector rods protruding out of the first surface according to the numerical values fed back by the plurality of pressure sensors which are communicated with the plurality of back pressure chambers in a one-to-one correspondence manner.

In some embodiments, the control method further comprises:

and determining the first distance, and controlling at least one ejector rod to displace along the first direction when the first distance is in a first preset range, so as to adjust the first distance.

In some embodiments, the value of the pressure sensor has a monotonic correspondence with the first distance when the first distance is within the first preset range.

The embodiment of the disclosure provides a wafer bearing device, which comprises a wafer bearing table, a first bearing plate and a second bearing plate, wherein the wafer bearing table is provided with a first surface and a second surface which are oppositely arranged, and the first surface is used for bearing a wafer; a plurality of ejector pins for contacting the wafer and displacing along a first direction perpendicular to the first surface; a plurality of back pressure chambers located on one side of the second surface of the wafer carrier; each back pressure chamber includes; a plurality of pressure sensors in one-to-one communication with the plurality of back pressure chambers; a plurality of nozzles correspondingly communicated with the plurality of back pressure chambers; the plurality of nozzles are positioned at adjacent positions of the ejector rods corresponding to the nozzles, and the horizontal heights of the outlet ends of the plurality of nozzles are equal; the control module is used for controlling the plurality of ejector rods to move away from the first surface so as to enable the wafer to be away from the first surface, and the horizontal height of the outlet ends of the plurality of nozzles is lower than that of the contact ends of the plurality of ejector rods and the wafer; the plurality of nozzles are controlled to jet air towards the surface of the wafer, and a plurality of first distances of the plurality of ejector rods protruding out of the first surface are controlled according to the numerical values fed back by the plurality of pressure sensors, so that automatic adjustment of the protruding first surface (wafer bearing surface) of each ejector rod is realized, the wafer level is adjusted, broken pieces are reduced, the process yield is improved, the manual shutdown level adjustment condition can be reduced, and the equipment wafer flow process efficiency is improved.

Drawings

FIG. 1 is a schematic diagram of a wafer carrier apparatus according to an exemplary embodiment of the present disclosure;

FIG. 2 is a schematic view of an arrangement of lift pins on a wafer carrier according to one embodiment of the present disclosure;

FIG. 3 is a schematic view of a wafer carrier with nozzles according to an embodiment of the present disclosure;

FIG. 4 is a schematic view of an arrangement of lift pins and nozzles on a wafer carrier according to an embodiment of the disclosure;

FIG. 5 is a schematic view of a nozzle jet toward a wafer according to an embodiment of the present disclosure;

FIG. 6 is a graphical representation of the back pressure value versus first distance, according to an embodiment of the present disclosure;

FIG. 7 is a schematic diagram of a back pressure chamber shown in accordance with an embodiment of the present disclosure;

fig. 8 is a flowchart illustrating a control method of a wafer carrier according to an embodiment of the disclosure.

In the drawings (which are not necessarily drawn to scale), like numerals may describe similar components in different views. Like reference numerals having different letter suffixes may represent different instances of similar components. The drawings illustrate generally, by way of example and not by way of limitation, various embodiments discussed herein.

Detailed Description

Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the specific embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present disclosure. However, it will be apparent to one skilled in the art that the present disclosure may be practiced without one or more of these details. In other instances, well-known features have not been described in order to avoid obscuring the present disclosure; that is, not all features of an actual implementation are described in detail herein, and well-known functions and constructions are not described in detail.

In the drawings, the size of layers, regions, elements and their relative sizes may be exaggerated for clarity. Like numbers refer to like elements throughout.

It will be understood that when an element or layer is referred to as being "on" … …, "" adjacent to "… …," "connected to" or "coupled to" another element or layer, it can be directly on, adjacent to, connected to or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being "directly on" … …, "" directly adjacent to "… …," "directly connected to" or "directly coupled to" another element or layer, there are no intervening elements or layers present. It will be understood that, although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the present disclosure. When a second element, component, region, layer or section is discussed, it does not necessarily mean that the first element, component, region, layer or section is present in the present disclosure.

Spatially relative terms, such as "under … …," "under … …," "below," "under … …," "above … …," "above," and the like, may be used herein for ease of description to describe one element or feature's relationship to another element or feature as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use and operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements or features described as "under" or "beneath" other elements would then be oriented "on" the other elements or features. Thus, the exemplary terms "under … …" and "under … …" may include both an upper and a lower orientation. The device may be otherwise oriented (rotated 90 degrees or other orientations) and the spatially relative descriptors used herein interpreted accordingly.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term "and/or" includes any and all combinations of the associated listed items.

So that the manner in which the features and techniques of the disclosed embodiments can be understood in more detail, a more particular description of the embodiments of the disclosure, briefly summarized below, may be had by reference to the appended drawings, which are not intended to be limiting of the embodiments of the disclosure.

It should be appreciated that reference throughout this specification to "some embodiments" or "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. Thus, the appearances of the phrases "in some embodiments" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. It should be understood that, in various embodiments of the present disclosure, the sequence numbers of the foregoing processes do not mean the order of execution, and the order of execution of the processes should be determined by their functions and internal logic, and should not constitute any limitation on the implementation of the embodiments of the present disclosure. The foregoing embodiment numbers of the present disclosure are merely for description and do not represent advantages or disadvantages of the embodiments.

The methods disclosed in the several method embodiments provided in the present disclosure may be arbitrarily combined without collision to obtain a new method embodiment.

The wafer carrying device can be used for fixing the wafer, and the fixing mode can comprise electrostatic adsorption, vacuum adsorption or mechanical claw fixing and the like. The wafer carrier may include a wafer carrier for contacting, carrying the wafer, the wafer carrier may include a contact surface for electrostatic or vacuum suction, and the wafer carrier may include a gripper for providing a mechanical clamping force. The wafer carrier employing the electrostatic chuck principle may also be referred to as an electrostatic chuck (ESC Pad), and the wafer carrier employing the vacuum chuck principle may also be referred to as a vacuum chuck.

In some embodiments, the surface of the wafer carrier that contacts the wafer may be defined as a wafer carrier surface, when the wafer is adsorbed and fixed, one side surface of the wafer will be closely attached to the wafer carrier surface, and after the wafer process is completed, the electrostatic adsorption surface or the vacuum adsorption surface of the wafer carrier is desorbed, and the lift pins (or the ejector pins) of the wafer carrier lift up from the surface of the wafer carrier, so that the wafer is lifted up from the surface of the wafer carrier, so that the wafer has a certain distance from the surface of the wafer carrier, and the mechanical arm of the machine is convenient to grasp. The ejector rod can be arranged in the wafer bearing table, and a motion motor can be arranged in the wafer bearing table and used for controlling the ejector rod to move upwards from the wafer bearing table to a certain distance away from the wafer bearing surface so as to jack up the wafer. The contact end of the ejector rod and the wafer can be flush with the wafer bearing surface when the wafer is not ejected.

In other embodiments, for a wafer carrier employing electrostatic adsorption, the lift pins of the wafer carrier may protrude above the wafer carrier by a certain height during the wafer processing, so as to facilitate heat dissipation or heating of the wafer and maintain the temperature of the wafer processing stable. After the wafer process is completed, the contact end of the ejector rod and the wafer surface can be flush with the surface of the wafer bearing table.

In order to keep the stability and the level of the wafer when the ejector rods jack up the wafer, a plurality of ejector rods, such as more than or equal to 3 ejector rods, are arranged, when each ejector rod moves perpendicular to the wafer bearing surface, the heights of the ejector rods protruding out of the wafer bearing surface are equal or are kept equal within a certain error range, so that the risk of wafer breakage caused by non-level or overlarge inclination angle of the wafer is reduced. In some etching machines, the lift pins of the wafer carrier protrude from the wafer carrier surface by different heights, which results in uneven or excessively large inclination angle of the wafer, and thus uneven etching rates of different portions of the wafer, resulting in poor uniformity of the etched structure of the wafer. In some deposition coating machines, the lift pins of the wafer carrier have different heights protruding from the wafer carrier surface, resulting in poor uniformity of the film thickness across different portions of the wafer. The adjustment of the plurality of ejector rod levels is beneficial to reducing wafer fragments and improving the process yield.

In accordance with aspects of embodiments of the present disclosure, fig. 1 provides a wafer carrier apparatus 100, comprising:

the wafer carrying table 101 is provided with a first surface and a second surface which are oppositely arranged, wherein the first surface is used for carrying a wafer;

a plurality of lift pins 102, displaced in a first direction perpendicular to the first surface, for contacting the wafer to lift the wafer dome away from the first surface; the first direction may be the z direction in fig. 1, the first surface may be the upper surface of the positive z direction, the first surface may be a wafer bearing surface contacting the wafer surface, the wafer bearing surface may contact the front or back surface of the wafer, and the x and y directions are perpendicular to the z direction.

A driving member 104 connected to the plurality of jack 102 to displace the plurality of jack 102 in a first direction;

the control module is used for controlling the driving part 104 to provide displacement power so that the plurality of ejector rods 102 protrude out of the first surface by a certain distance to jack up the wafer.

The wafer carrier apparatus shown in fig. 1 may fix a wafer using vacuum adsorption or electrostatic adsorption. The electrostatically attracted wafer carrier is illustrated here as an example. The surface of the wafer carrier 101 contacting the wafer is a wafer carrier surface, and the wafer carrier surface is a dielectric material. An electrode may be disposed in the wafer carrier 101 below the wafer carrier surface to generate electrostatic attraction, and a heating device may be disposed to provide a process temperature for the wafer. The heating device may use a heated inert gas as a medium to flow over and contact the wafer to heat the wafer. The cooling apparatus may use a cooling medium circulating in the cooling tube to reduce the temperature of the wafer carrier 101.

The disclosed embodiments are not limited to wafer dimensions, which by way of example generally refer to the diameter of a wafer, which may include, but are not limited to, 6 inches (150 mm), 8 inches (200 mm), 12 inches (300 mm) as is commonly used. 6-inch and 8-inch wafers may be used primarily for mid-low end chip fabrication, and 12-inch wafers may be used primarily for 14nm and below chip fabrication. The wafer carrier 101 according to the embodiments of the present disclosure may be adapted according to the wafer size, and may be increased in size to fit larger-sized wafers, such as 14 inches, 15 inches, 16 inches, 20 inches, etc., to fit more advanced wafer fabrication processes, and reduce fabrication costs.

Referring to fig. 2, in the embodiment of the disclosure, taking 3 lifters 102 as an example, the wafer carrying platform 101 may be circular, the distance between each lifter 102 and the center of the circle of the wafer carrying platform 101 may be equal, the 3 lifters 102 are symmetrically distributed on the wafer carrying surface, and 3 connecting lines between the 3 lifters 102 and the center of the circle of the wafer carrying surface divide the wafer carrying surface equally.

In some embodiments, the contact end of the lift pins 102 with the wafer may be flush with the wafer bearing surface when the lift pins 102 are not lifting the wafer dome away from the wafer bearing surface. The lift pins 102 may include, but are not limited to, a polyhedron or cylinder, and the orthographic projection of the contact end of the lift pins 102 with the wafer on the wafer bearing surface may include, but is not limited to, a rectangular, circular, or other shape. The drive member 104 may also be referred to as a drive, including but not limited to an electric motor, a motor, or a cylinder, coupled to the jack 102 directly or via a drive shaft, to provide power to the jack 102 to move up and down in the z-direction.

The plurality of ejector rods 102 can independently displace up and down in the z direction, the plurality of ejector rods 102 can also be connected to a connecting rod 103, the connecting rod 103 can be a ring-shaped connecting rod 103 extending in the xoy plane, the ring-shaped connecting rod 103 is connected with a driving part 104 through a transmission connecting rod 105, the driving part 104 provides power to enable the transmission connecting rod 105 to displace up and down in the z direction, and the ring-shaped connecting rod 103 is driven to displace up and down so as to enable the ejector rods 102 to displace up and down. The driving part 104 illustrated in fig. 1 may be a pneumatic part, which controls the lifting of the transmission link 105 through a pneumatic valve, the ring link 103 connected to the jack 102, or the ring link 103 provided with the jack 102 is screw-coupled with the side of the transmission link 105.

In some embodiments, the ring-shaped connecting rod 103 in fig. 1 can make the plurality of ejector pins 102 move up and down at the same time, so as to reduce accidental deviation of the ejector pins 102 protruding from the wafer carrying surface, which is beneficial to controlling the lifting of the plurality of ejector pins 102 and simplifying the mechanical structure. The annular connecting rod 103 of the ejector rod 102 is locked on the transmission connecting rod 105 through side threads, the annular connecting rod 103 is offset due to uneven locking torque or assembly deviation, the height of the ejector rod 102 protruding out of the wafer bearing surface is inconsistent, the wafer is offset, and fragments are generated or the process yield is reduced. A more pronounced deviation may exist between the side jack 102 closer to the drive link 105 and the side jack 102 farther from the drive link 105.

The wafer carrying device in fig. 1 has a simple structure, but cannot accurately control the vertical displacement height of the plurality of ejector rods 102, and the non-level of the ring-shaped connecting rod 103 is caused by the human factor and the vertical movement of the side screw locking and fastening of the transmission ejector rods 102, so that the non-level of the plurality of ejector rods 102 is caused, and the non-level of the wafer is caused. When the level between the push rods 102 needs to be adjusted, the wafer carrying device needs to be stopped and disassembled for maintenance adjustment, and the measuring tool is used for manually measuring and adjusting the level of the push rods 102. It is difficult to adjust the absolute levels of the plurality of jack 102 due to errors in the precision of the measuring tool and human work. The ejector pins 102 are generally lifted up to a preset position, where the preset position may be a position where the ejector pins 102 stop after the wafer is far away from the wafer bearing surface, when the ejector pins 102 are at the preset position, the distance between the contact end of the ejector pins 102 and the wafer bearing surface is 2-3mm, which is difficult to adjust to an absolute level, and in the process of lifting and lowering the ejector pins 102 by the movement of the transmission link 105, the offset or loosening of the ejector pins 102 may further cause non-level, increase the inclination angle, but is difficult to adjust the levelness of each ejector pin 102.

The embodiment of the disclosure provides a wafer carrying device, which can manually adjust the level of a push rod without manual disassembly under a certain working condition, can automatically adjust the height of each push rod protruding from a wafer carrying surface, and can increase the flow sheet processing efficiency of a wafer carrying table while adjusting the levelness of the push rod.

In accordance with aspects of the disclosed embodiments, fig. 3 provides a wafer carrier 200, the wafer carrier 200 comprising:

a wafer carrier 201 (the wafer carrier 201 is shown in the top bar and nozzle profile of fig. 4) having oppositely disposed first and second surfaces, the first surface for carrying a wafer;

a plurality of lift pins 202 contacting the wafer and being displaced in a first direction perpendicular to the first surface;

a plurality of back pressure chambers 203 located at one side of the second surface of the wafer stage 201; a plurality of pressure sensors 204 in one-to-one communication with the plurality of back pressure chambers 203;

a plurality of nozzles 205 in one-to-one correspondence with the plurality of back pressure chambers 203; the plurality of nozzles 205 are positioned adjacent to the corresponding ejector rods 202, and the horizontal heights of the outlet ends of the plurality of nozzles 205 are equal;

a control module, configured to control the displacement of the plurality of lift pins 202 away from the first surface to enable the wafer to be away from the first surface, wherein the level of the outlet ends of the plurality of nozzles 205 is lower than the level of the contact ends of the plurality of lift pins 202 and the wafer; the nozzles 205 are controlled to jet air toward the wafer surface, and the lift pins 202 are controlled to protrude a plurality of first distances from the first surface according to the values fed back by the pressure sensors 204, so as to level the wafer.

Illustratively, the first surface may be an upper surface in the positive z-direction of fig. 3 for contacting a carrier wafer, which may also be referred to as a wafer carrier surface, which includes a dielectric material; the second surface is the lower surface of the wafer carrier 201 in the negative z direction. The wafer carrier 201 may be an electrostatic chuck, and electrodes, heating devices, etc. are integrated inside the wafer carrier 201, i.e., in the area between the first surface and the second surface. One end of the plurality of lift pins 202, which is not in contact with the wafer, is also located inside the wafer stage 201 or outside the wafer stage 201, and is connected to the driving member 206 to realize up-and-down displacement in the z direction.

Referring to fig. 4, a schematic diagram of the distribution of 3 nozzles 205 to 3 lift pins 202 on a wafer carrier is shown, where the nozzles 205 and their corresponding lift pins 202 may be as close as possible, but not in contact, and further lift pins 202 and further nozzles 205 may be provided. In the embodiment of the disclosure, taking 3 ejector pins 202 as an example, each ejector pin 202 may be connected to one driving component 206 to realize independent up-and-down displacement, so as to independently adjust the protruding height of the ejector pins 202 from the wafer carrying surface. The wafer bearing surface can be circular, the distance between each ejector rod 202 and the circle center of the wafer bearing surface can be equal, 3 ejector rods 202 are symmetrically distributed on the wafer bearing surface, and 3 connecting lines between the 3 ejector rods 202 and the circle center of the wafer bearing surface divide the wafer bearing surface evenly.

Each lift pin 202 is driven by the driving component 206 to vertically displace in the z direction perpendicular to the wafer carrying surface, and when the wafer is processed or the wafer is required to be tightly attached to the wafer carrying surface, the contact end of the lift pin 202 and the wafer is level with the wafer carrying surface; the lift pins 202 are displaced upward to lift the wafer when the wafer is removed from the wafer carrier surface during the wafer processing. When the lift pins 202 do not lift or lift the wafer, one end of the lift pins 202 is in contact with the wafer.

At one side of each of the push rods 202, a back pressure chamber 203 is provided corresponding to the push rods 202, 3 push rods 202 are provided with 3 back pressure chambers 203, and each back pressure chamber 203 is connected with a pressure sensor 204 to test the back pressure of the back pressure chamber 203. Here, the communication between the pressure sensor 204 and the back pressure chamber 203 means pressure communication, the pressure sensor 204 may be provided inside the back pressure chamber 203, or the pressure sensor 204 may be provided outside the back pressure chamber 203, a test port 2033 may be provided in the back pressure chamber 203, and the test port 2033 and the pressure sensor 204 may be connected by a pipe. Test port 2033 is shown in FIG. 7.

In some embodiments, the back pressure chamber 203 is provided with a test branch, and a pressure sensor 204 is provided in the branch, and an opening of the test branch connected to the back pressure chamber 203 may be a test port 2033. Referring to fig. 7, the back pressure chamber 203 may further include an air source port 2031 for externally connecting an air source to provide a stable air pressure to the back pressure chamber 203, and the back pressure chamber 203 may further include an air jet port 2032 for externally connecting an air outlet device. For example, the air jet port 2032 may be connected to the nozzle 205 through a pipe, and the air in the back pressure chamber 203 is transferred to the nozzle 205 through the air jet port 2032 and the pipe, and the nozzle 205 jets air outward. The shape of the back pressure chamber 203 may include, but is not limited to, a square, a rectangular parallelepiped, or a cylindrical shape. The nozzle 205 may be configured to jet the wafer with a certain level of the nozzle 205, i.e., with reference to the nozzle 205, and the distance between the nozzle 205 and the wafer may be characterized by the measured value of the back pressure sensor.

The measurement principle of the embodiment of the disclosure is to use the flow rate and the pressure of the gas to characterize the distance, and in the flowing process of the gas, if the gas encounters an obstacle, the flow rate and the pressure of the gas have inverse proportion relation with the distance of the obstacle from a gas source. In some embodiments, after the gas source gas provided by the plant is regulated by the pressure limiting valve or the regulating valve and is secondarily distributed to the working pressure, the gas source gas is delivered to the constant gas flow device 207 of fig. 3, and the constant gas flow device 207 comprises a pressure regulating valve, a gas distributor and the like, so as to deliver the constant pressure gas to each back pressure chamber 203. The source gas provided by the plant may include, but is not limited to: dry compressed air, dry compressed nitrogen, dry compressed helium or dry other compressed inert gas.

The air source is connected to the back pressure chamber 203 through the air source port 2031, the air source air flow enters the air source port 2031 to generate a first air resistance, and because the aperture of the air source port 2031 is smaller, the air source port 2031 will cause a larger resistance to the flow of the air source air flow, and only a smaller flow of air enters the back pressure chamber 203 through the air source port 2031. Referring to the schematic diagram of the jet simulation of the jet nozzle 205 toward the wafer shown in fig. 5, the gas in the back pressure chamber 203 is jetted toward the wafer through the jet nozzle 205, and the gas flow encounters the barrier of the wafer, and there is a portion of the gas flow turned back toward the jet nozzle 205, so that a second gas barrier is generated in the back pressure chamber 203, and a back pressure is generated, and the pressure sensor 204 senses the back pressure value and converts the pressure signal into an electrical signal to output to the control module. The back pressure in the back pressure chamber 203 may vary with the distance between the nozzle 205 and the wafer surface that blocks the gas, and as the nozzle 205 approaches the wafer, the resistance of the wafer to the gas flow ejected from the nozzle 205 increases, the second gas resistance in the back pressure chamber 203 increases, and the back pressure in the back pressure chamber 203 increases; conversely, when the nozzle 205 is away from the wafer, the resistance of the wafer to the gas flow emitted from the nozzle 205 decreases, and the second gas lock in the back pressure chamber 203 decreases, and the back pressure of the back pressure chamber 203 decreases. When the wafer contacts the nozzle 205, the back pressure of the back pressure chamber 203 reaches a maximum value and can be equal to the gas supply pressure of the gas supply port 2031 of the back pressure chamber 203.

The distance between the nozzle 205 and the wafer is different, the back pressure of the back pressure guiding chamber 203 is different, the pressure value sensed by the pressure sensor 204 is different, the distance between the nozzle 205 and the wafer can be represented by the different back pressure values of the back pressure chamber 203 sensed by the pressure sensor 204, the horizontal height of the nozzle 205 is fixed, the wafer is lifted away from the nozzle 205 by the ejector rods 202, the distance between one end of each ejector rod 202, which contacts the wafer, and the wafer bearing surface can be represented by taking the horizontal height of each nozzle 205 as a reference, and the first distance of each ejector rod 202 protruding from the wafer bearing surface can be accurately adjusted, so that the first distances of the ejector rods 202 protruding from the wafer bearing surface are equal, or are basically equal in a certain process control range, so that the wafer level or the inclination angle of the wafer can be basically horizontal in the process control range. Illustratively, the plurality of lift pins 202 protrude from the wafer carrier surface by a plurality of first distances, which may be within a certain range, for example, 2-3 mm, the plurality of first distances being equal to indicate the wafer level, or within a certain range of height differences, which may be: 0 to 0.5mm. It is understood that the first distance and the height difference shown in the embodiments of the present disclosure are merely examples, and the adjustment and the adaptation can be performed according to different process requirements and machine design parameters. Note that, in order to improve the accuracy of the back pressure value sensed by the pressure sensor 204, the plurality of back pressure chambers 203 provided by the embodiment of the present disclosure may be identical in model, and the plurality of nozzles 205 may be identical in model.

Referring to fig. 3, each nozzle 205 is connected to the back pressure chamber 203 through a pipe, each nozzle 205 is disposed adjacent to its corresponding jack 202, near its corresponding jack 202 but not rising or falling with the jack 202, the nozzles 205 are fixed and the level of the outlet ends of the nozzles 205 is equal, and the outlet ends of the plurality of nozzles 205 are maintained level or level within a certain error range. The outlet end of the nozzle 205 may be below the wafer bearing surface or may be flush with the wafer bearing surface. When the control module controls the ejector rod 202 to start to move away from the wafer bearing surface to jack up the wafer, the control nozzle 205 is controlled to jet air towards the wafer, the control pressure sensor 204 senses the back pressure value in real time, and the distance between the wafer and the nozzle 205 is determined according to the value fed back by the pressure sensor 204, so that the first distance of the ejector rod 202 protruding out of the wafer bearing surface is determined.

In some embodiments, when the first distance of a certain lift pin 202 reaches a preset height or a preset height range, the lift pins 202 stop moving, and all lift pins 202 reach the preset height or the preset height range, so that the contact ends of all lift pins 202 and the wafer are at the same level, so that the wafer is horizontal. In other embodiments, the control module may control the lift pins 202 to a predetermined height, then control the nozzles 205 to jet the wafer to determine whether the height of the lift pins 202 is horizontal, and then control at least one lift pin 202 to descend or ascend according to the value of the pressure sensor 204 to adjust the horizontal heights of the lift pins 202 so as to level the wafer. Each pressure sensor 204 corresponds to each ejector rod 202, and can independently control the first distance of each ejector rod 202 protruding the wafer bearing surface so as to adjust the wafer level, thereby reducing the breaking risk caused by non-level of the wafer, improving the process yield, reducing the manual level adjustment caused by shutdown, and improving the equipment wafer flow process efficiency.

In some embodiments, the outlet ends of the plurality of nozzles 205 are flush with the first surface of the wafer carrier 201. The outlet end of the nozzle 205 is flush with the wafer bearing surface (the first surface), which is beneficial to the adhesion of the wafer bearing surface, improves electrostatic attraction, reduces the risk of wafer moving fragments, and improves the process yield. In other embodiments, the nozzle 205 may be positioned below the wafer carrier, and the wafer carrier 201 may be provided with openings for delivering gas from the nozzle 205 and blowing it toward the wafer. Alternatively, the nozzle 205 is located below the second surface of the wafer carrier 201 and outside the wafer carrier 201, before the lift pins 202 are lifted, the nozzle 205 is displaced to an arbitrary position in the wafer carrier 201 along a direction perpendicular to the wafer carrier surface, for example, may be lifted to a level with the wafer carrier surface of the wafer carrier 201, and then is blown toward the wafer to obtain a first distance that the lift pins 202 protrude from the wafer carrier surface.

In some embodiments, the control module is configured to determine a first distance, and when the first distance is within a first predetermined range, control the displacement of the at least one lift pin 202 in a first direction, and adjust the first distance to level the wafer.

In some embodiments, the value of the pressure sensor 204 has a monotonic correspondence with the first distance when the first distance is within a first preset range.

The back pressure value sensed by the pressure sensor 204 of the embodiment of the disclosure may be in an inverse proportion relation to the distance between the nozzle 205 and the wafer, the back pressure value sensed by the pressure sensor 204 is in an inverse proportion relation to the first distance of the ejector rod 202 protruding out of the wafer bearing surface, and when the outlet end of the nozzle 205 is flush with the wafer bearing surface, the first distance is equal to the distance between the nozzle 205 and the wafer; when the outlet end of the nozzle 205 is lower than the wafer bearing surface, the first distance is the distance between the nozzle 205 and the wafer minus the distance between the outlet end of the nozzle 205 and the wafer bearing surface. Embodiments of the present disclosure are illustrated with the first distance being equal to the distance between the nozzle 205 and the wafer as an example. Fig. 6 shows a graph of back pressure versus first distance for an embodiment of the present disclosure.

In fig. 6, when the first distance is in the range of a-b, there is a more significant monotonic correspondence between the back pressure value and the first distance, and when the first distance is changed, the change of the back pressure value caused is more obvious, which is beneficial to the acquisition of the back pressure value by the pressure sensor 204, improving the back pressure sensing accuracy, being beneficial to the height control of the protruding wafer bearing surface of the ejector rod 202, and improving the levelness control accuracy of the ejector rod 202.

In some embodiments, a level measurement device may be disposed on or outside the wafer carrier, for measuring or recording a first distance of the lift pins 202, and feeding back a signal representing the first distance to the control module, where the first preset range may be a-b in fig. 6 or the first preset range may fall within a-b when the control module determines that the first distance is within the first preset range, and at least one lift pin 202 is adjusted to displace downward or upward along a direction perpendicular to the wafer carrier surface, and at this time, the nozzle 205 sprays air to the wafer, and controls the distance of downward or upward displacement of the lift pins 202 according to the value fed back by the pressure sensor 204, so as to adjust the first distance of the lift pins 202 to level the wafer. When the first distance is determined to be outside the first preset range, for example, the first distance is smaller than a or larger than b, the change of the first distance causes less obvious numerical value change of the pressure sensor 204, the control module considers that the up-and-down displacement of the adjusting ejector rod 202 has a certain risk, the alarm device can give an alarm, the automatic adjustment of the height of the ejector rod 202 is stopped, the operation of the wafer bearing device can be stopped, and the stop manual adjustment of the ejector rod 202 is performed; after the first distance between the manual adjustment pins 202 is within the first preset range, the recovery control module controls the driving components 206 such as the motion motor to automatically adjust the height of the pins 202 and the nozzles 205 to jet air, and adjusts the specific value of the first distance between the pins 202 according to the value of the pressure sensor 204, so as to adjust the wafer level. In other embodiments, the value of pressure sensor 204 may be utilized to determine whether the first distance is within a first predetermined range. For example, the pressure sensor 204 senses that the back pressure is greater than the value P1 in fig. 6, and can determine that the first distance is less than a; or the pressure sensor 204 senses that the back pressure value is smaller than the P2 value, it may determine that the first distance is greater than b; the first distance is not within a first preset range. In contrast, when the pressure sensor 204 senses that the back pressure value is between P1 and P2, it is determined that the first distance is within the first preset range.

In some embodiments, the shape of the nozzle 205 may be optimized, the air supply pressure may be optimized, the test data may be subjected to a fitting analysis, and within a first preset range, the back pressure value may have a linear relationship or be fitted to a linear relationship with a first distance, where a 1mm change in the first distance corresponds to a 0.02pa pressure change in the back pressure value. Specifically, the first distance was increased by 1mm and the back pressure value was reduced by 0.02pa.

In some embodiments, referring to fig. 7, the back pressure chamber 203 includes a gas source port 2031, a gas injection port 2032, and a test port 2033; the air source port 2031 is used for externally connecting an air source, and the air jet port 2032 is used for communicating with the corresponding nozzle 205; the test port 2033 is for communicating with a corresponding pressure sensor 204. The air source port 2031 and the air source can be connected through a pipeline, the nozzle 205 and the air jet port 2032 can be connected through a pipeline, and the test port 2033 can be connected with the pressure sensor 204 through a pipeline.

In some embodiments, the back pressure chamber 203 is provided with a test branch, and a pressure sensor 204 is provided in the branch, and an opening of the test branch connected to the back pressure chamber 203 may be a test port 2033.

In some embodiments, the test port 2033 is on the inner wall of the side opposite the air injection port 2032; the air source port 2031 is provided on an inner wall of one side adjacent to the test port 2033, and the back pressure chamber 203 may have a square or rectangular parallelepiped shape.

As shown in fig. 5, when the nozzle 205 jets gas toward the wafer, a part of the gas is blocked by the wafer and turned back toward the nozzle 205, thereby generating a back pressure in the back pressure chamber 203. Referring to fig. 7, the test port 2033 may be disposed opposite to the air injection port 2032, and the pressure sensor 204 may directly sense the back pressure on the front surface, so as to reduce the pressure drop caused by the blocking of the side wall of the back pressure chamber 203, and improve the accuracy of obtaining the back pressure value. The air source port 2031 may not be opposite to the test port 2033, so that the pressure of the air source port 2031 is reduced to be excessively high and directly applied to the pressure sensor 204, thereby interfering with the acquisition of the back pressure value and improving the back pressure sensing accuracy.

In some embodiments, the wafer carrier includes at least 3 lift pins 202.

According to some aspects of embodiments of the present disclosure, an etching machine is provided, including the wafer carrier described above, where the wafer carrier is located in the etching chamber.

Illustratively, the etching tool may include a dry etching tool, which may further include a plasma generating device that plasmatizes the process gas and a plasma deflection device that accelerates the plasma toward the wafer for etching the wafer. Wafer bearing device

In other embodiments, the wafer carrier apparatus may be used as a tool assembly for any tool apparatus that is required to hold a wafer, such as a chemical or physical deposition tool, a photolithography tool, a particle inspection tool, a film thickness measurement tool, etc.

In some embodiments, the etching station further comprises:

a level measurement device positioned in the etching cavity and used for measuring the first distance; when the first distance is within a first preset range, at least one ejector rod 202 is controlled to move along the first direction, and the first distance is adjusted so as to enable the wafer to be horizontal. The central control module of the etching machine controls the control module of the wafer carrying device, and the control module of the wafer carrying device controls the displacement of the ejector rod 202, controls the air injection of the nozzle 205 and controls other actions of the wafer carrying device in response to the instruction of the central control module.

According to aspects of the embodiments of the present disclosure, fig. 8 provides a control method of a wafer carrier, with reference to fig. 8, the control method includes:

s101: placing a wafer on a first surface of a wafer carrier 201;

s102: displacing the plurality of lift pins 202 away from the first surface in a first direction perpendicular to the first surface, so that the wafer is away from the first surface, and the level of the outlet ends of the plurality of nozzles 205 is lower than the level of the contact ends of the plurality of lift pins 202 with the wafer; wherein the plurality of nozzles 205 are in one-to-one correspondence with the plurality of back pressure chambers 203, the plurality of nozzles 205 are located at adjacent positions of the ejector pins 202 corresponding to the plurality of nozzles 205, and the outlet ends of the plurality of nozzles 205 have equal horizontal heights;

S103: causing the plurality of nozzles 205 to jet air toward the wafer surface; and controlling a plurality of first distances of the plurality of ejector rods 202 protruding out of the first surface according to the values fed back by the plurality of pressure sensors 204 which are communicated with the plurality of back pressure chambers 203 in a one-to-one correspondence manner, so that the wafer is horizontal.

The wafer carrier according to the embodiments of the present disclosure may be used as a tool assembly, and may be applied to any tool equipment that needs to fix a wafer, including but not limited to: etching equipment, chemical or physical deposition equipment, lithography equipment, particle detection equipment, film thickness measurement equipment, etc. The control method of the wafer carrier according to the embodiments of the present disclosure may be part of the control method of the platform device of the integrated wafer carrier, for example, may be part of the control method of the etching platform, and the sequence of the method steps is not limited, and may be adapted according to the design of the specific process. For example, the control method of the etching machine of the integrated wafer carrying device may include: the robot arm transfers the wafer to the wafer carrier 201 of the wafer carrier within the etch chamber; starting the electrostatic adsorption function of the wafer carrying device to complete wafer adsorption, wherein the contact end of the ejector rod 202 and the wafer is flush with the wafer carrying surface (the first surface of the wafer carrying table 201); etching the wafer; after etching, the electrostatic adsorption function is closed, the adsorption of the wafer by the wafer bearing table 201 is removed, the ejector rods 202 are lifted up along the direction vertical to the wafer bearing surface to jack up the wafer so as to enable the wafer to be far away from the wafer bearing surface, the plurality of nozzles 205 are enabled to jet air towards the surface of the wafer, and the plurality of ejector rods 202 are controlled to protrude a plurality of first distances from the first surface according to the numerical values fed back by the plurality of pressure sensors 204 which are communicated with the plurality of back pressure chambers 203 in a one-to-one correspondence manner so as to enable the wafer to be horizontal; the robot arm moves the wafer out of the etch chamber. The lift pins 202 are raised and the nozzles 205 may simultaneously begin to jet gas toward the wafer.

In some embodiments, the control method further comprises:

and determining the first distance, and controlling at least one ejector rod 202 to move along the first direction when the first distance is in a first preset range, so as to adjust the first distance to enable the wafer to be horizontal.

In some embodiments, the value of the pressure sensor 204 has a monotonic correspondence with the first distance when the first distance is within the first preset range.

The foregoing is merely specific embodiments of the disclosure, but the protection scope of the disclosure is not limited thereto, and any person skilled in the art can easily think about changes or substitutions within the technical scope of the disclosure, and it is intended to cover the scope of the disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope of the claims.

Claims (12)

1. A wafer carrier, comprising:

the wafer bearing table is provided with a first surface and a second surface which are oppositely arranged, and the first surface is used for bearing a wafer;

a plurality of lift pins for contacting the wafer and being displaced in a first direction perpendicular to the first surface;

a plurality of back pressure chambers located on one side of the second surface of the wafer carrier;

A plurality of pressure sensors in one-to-one communication with the plurality of back pressure chambers;

a plurality of nozzles in one-to-one correspondence with the plurality of back pressure chambers; the nozzles are positioned at adjacent positions of the ejector rods corresponding to the nozzles, and the horizontal heights of the outlet ends of the nozzles are equal;

the control module is used for controlling the displacement of the plurality of ejector rods away from the first surface to enable the wafer to be away from the first surface, and the horizontal height of the outlet ends of the plurality of nozzles is lower than that of the contact ends of the plurality of ejector rods and the wafer; and controlling a plurality of nozzles to jet air towards the surface of the wafer, and controlling a plurality of first distances of the ejector rods protruding out of the first surface according to the numerical values fed back by the pressure sensors.

2. The wafer carrier of claim 1, wherein the control module is further configured to determine the first distance, and when the first distance is within a first predetermined range, control displacement of at least one lift pin in the first direction to adjust the first distance.

3. The wafer carrier of claim 2, wherein the value of the pressure sensor has a monotonic correspondence with the first distance when the first distance is within the first predetermined range.

4. The wafer carrier of claim 1, wherein the outlet ends of the plurality of nozzles are flush with the first surface of the wafer carrier.

5. The wafer carrier of claim 1, wherein the back pressure chamber comprises a gas source port, a gas jet port, and a test port;

the air source port is used for being externally connected with an air source, and the air jet port is used for being communicated with the corresponding nozzle;

the test port is used for communicating the corresponding pressure sensor.

6. The wafer carrier of claim 5, wherein the test port is located on an inner wall of the side opposite the gas jet port; the air source port is positioned on the inner wall of one side adjacent to the test port.

7. The wafer carrier of claim 1, wherein the wafer carrier comprises at least 3 of the lift pins.

8. An etching tool comprising a wafer carrier according to any one of claims 1 to 7, wherein the wafer carrier is located within an etching chamber.

9. The etching tool of claim 8, further comprising:

a level measurement device positioned in the etching cavity and used for measuring the first distance; when the first distance is in a first preset range, controlling at least one ejector rod to displace along the first direction, and adjusting the first distance.

10. A method for controlling a wafer carrier, comprising:

placing a wafer on a first surface of a wafer carrying table;

displacing the plurality of ejector rods along a first direction perpendicular to the first surface and away from the first surface, so that the wafer is away from the first surface, and the level of the outlet ends of the plurality of nozzles is lower than the level of the contact ends of the plurality of ejector rods and the wafer; the plurality of nozzles are communicated with the plurality of back pressure chambers in a one-to-one correspondence manner, the plurality of nozzles are positioned at adjacent positions of the ejector rods corresponding to the plurality of nozzles, and the horizontal heights of the outlet ends of the plurality of nozzles are equal;

causing the plurality of nozzles to jet air toward the wafer surface; and controlling a plurality of first distances of the plurality of ejector rods protruding out of the first surface according to the numerical values fed back by the plurality of pressure sensors which are communicated with the plurality of back pressure chambers in a one-to-one correspondence manner.

11. The control method according to claim 10, characterized in that the control method further comprises:

and determining the first distance, and controlling at least one ejector rod to displace along the first direction when the first distance is in a first preset range, so as to adjust the first distance.

12. The control method according to claim 11, characterized in that the value of the pressure sensor has a monotonic correspondence with the first distance when the first distance is in the first preset range.