Wafer post-processing device, backside scrubbing equipment, method and processing equipment

Abstract

The present invention provides a wafer post-processing device, back side scrubbing equipment, method and processing equipment. The wafer post-processing device includes: a scrubbing assembly, a supporting assembly and a clamping assembly; the scrubbing assembly includes a scrubbing arm, a scrubbing head and a scrubbing pad, and the scrubbing pad is installed on the scrubbing head; the supporting assembly includes a supporting arm and a supporting head, and a plurality of supporting fluid spray holes are distributed on the surface of the supporting head; when processing the wafer, the clamping assembly clamps and drives the wafer to rotate, and the wafer is located between the scrubbing pad and the supporting head, and there is a gap between the surface of the supporting head and the front side of the wafer, the scrubbing pad adheres to the back side of the wafer with scrubbing pressure and rotates, the scrubbing head and the supporting head swing back and forth, and always keep aligned during the swinging process, the scrubbing fluid channel supplies scrubbing fluid to the back side of the wafer, and the supporting fluid spray holes continuously spray supporting fluid to the front side of the wafer, so that the surface of the supporting head does not contact the front side of the wafer; thereby, the contaminants on the back side of the wafer are removed without damaging the front side of the wafer.

Description

Technical Field

[0001] The present invention belongs to the technical field of chemical mechanical polishing and is used for processing semiconductor chips. Specifically, it relates to a wafer post-processing device, backside scrubbing equipment, method and processing equipment. Background Art

[0002] Chemical mechanical polishing (CMP) equipment is currently the only equipment that can achieve global flattening of the surface of semiconductor wafers. As the process nodes of integrated circuits continue to improve, the number of CMP process steps in the entire manufacturing process increases, and the polishing requirements for different wafer types are also diverse.

[0003] After the wafer passes through the CMP equipment, the front side of the wafer undergoes polishing and cleaning processes to ensure that the roughness and particle removal on the front side meet the requirements of subsequent processes. However, the back side of the wafer may be contaminated before polishing. The pressure applied to the back side during polishing causes the contaminants to adhere more tightly to the back side of the wafer, making it impossible to effectively remove them during subsequent cleaning, thus affecting subsequent processes. Summary of the Invention

[0004] In view of this, the present invention provides a wafer post-processing device, a backside scrubbing device, a method and a processing device, thereby solving or at least alleviating one or more of the above-mentioned problems and other problems existing in the prior art.

[0005] A first aspect of the present invention provides a wafer post-processing device, comprising: a scrubbing assembly, a supporting assembly, and a clamping assembly;

[0006] The scrubbing assembly includes a scrubbing arm, a scrubbing head, a scrubbing pad, and a scrubbing fluid passage, wherein the scrubbing pad is mounted on the scrubbing head;

[0007] The support assembly includes a support arm and a support head, and the surface of the support head has a plurality of support fluid spray holes;

[0008] When processing wafers,

[0009] The clamping assembly clamps and drives the wafer to rotate, and the wafer is located between the scrubbing pad and the support head. There is a gap between the surface of the support head and the front of the wafer.

[0010] The scrubbing pad adheres to the back of the wafer with scrubbing pressure and rotates under the drive of the scrubbing head. The scrubbing fluid channel supplies scrubbing fluid to the back of the wafer.

[0011] The scrubbing head and the supporting head swing back and forth and always keep aligned during the swinging process, and the supporting fluid nozzle continuously sprays the supporting fluid toward the front surface of the wafer so that the surface of the supporting head does not contact the front surface of the wafer;

[0012] Thus, the contaminants on the back side of the wafer are removed without damaging the front side of the wafer.

[0013] Optionally, the wafer post-processing device further comprises a dressing assembly for dressing the scrubbing pad, wherein the dressing assembly is arranged on a dressing swing path of the scrubbing head, and the scrubbing head moves along the dressing swing path to the dressing assembly;

[0014] The trimming swing path does not overlap with the scrubbing swing path of the scrubbing head when processing the wafer, so as to prevent contaminants generated when processing the wafer from sputtering to the trimming assembly.

[0015] Optionally, the scrubbing assembly further comprises a rotary lifting element, wherein the rotary lifting element is connected to one end of the lower surface of the scrubbing arm, and the scrubbing head is arranged at the other end of the lower surface of the scrubbing arm;

[0016] The rotary lifting element is used to make the scrubbing arm drive the scrubbing head to swing and lift, and adjust the scrubbing pressure by lifting the scrubbing head;

[0017] When processing a wafer, the scrubbing head swings back and forth between the center and the edge of the wafer, and the scrubbing pressure is adjusted according to the position of the scrubbing head to cause the wafer to deform.

[0018] Optionally, adjusting the scrubbing pressure according to the position of the scrubbing head includes:

[0019] When the scrubbing head is located at the center of the wafer, the scrubbing pressure is adjusted so that the center of the wafer has an upward warp of 0° to 2° relative to the edge of the wafer, thereby guiding the contaminants to flow toward the edge of the wafer along the arc surface formed by the upward warp; and / or,

[0020] When the scrubbing head is located at the edge of the wafer, the scrubbing pressure is adjusted to level the wafer to prevent the clamping assembly from slipping.

[0021] Optionally, the support assembly further comprises a rotating element coaxially arranged with the rotating lifting element, the rotating element being connected to one end of the upper surface of the support arm, and the supporting head being arranged at the other end of the upper surface of the support arm;

[0022] The rotary lifting element includes a rotary motor and a coupling mechanism. The coupling mechanism drives the rotary lifting element and the rotary element to rotate synchronously when the rotary motor rotates through coupling. The coupling mechanism drives only the rotary lifting element to rotate when the rotary motor rotates through decoupling.

[0023] Optionally, the clamping assembly includes four clamping elements distributed at equal intervals, wherein:

[0024] The first clamping element and the second clamping element are respectively installed at two ends of the first connecting mechanism, and the first connecting mechanism and the first clamping element are located between the scrubbing arm and the support arm in the vertical direction to avoid interference with the swinging support arm;

[0025] The third clamping element and the fourth clamping element are respectively mounted at two ends of the second connecting mechanism;

[0026] A line connecting the first clamping element and the second clamping element is parallel to a line connecting the third clamping element and the fourth clamping element;

[0027] The first connecting mechanism and the second connecting mechanism move relative to each other in a horizontal direction, so that the four clamping elements move closer to or farther away from each other, thereby clamping the wafer when they move closer and releasing the wafer when they move farther away.

[0028] Optionally, the first connecting mechanism is a U-shaped plate with an opening facing the wafer;

[0029] The first clamping element and the second clamping element are respectively mounted on two ends of the upper surface of the first connecting mechanism, and in a horizontal projection, the first clamping element overlaps with the swing path of the support arm, while the second clamping element does not overlap with the swing path of the support arm;

[0030] A connecting mechanism supporting member is connected to a lower surface of the first connecting mechanism to support the first connecting mechanism, the connecting mechanism supporting member being opposite to the second clamping member.

[0031] Optionally, the connecting mechanism support element can drive the first connecting structure to move horizontally relative to the second connecting structure, and drive the second clamping element to rotate;

[0032] The scrubbing head reciprocates between the center of the wafer and the second clamping element.

[0033] Optionally, the scrubbing assembly further includes a scrubbing head shaft, and the scrubbing fluid channel sequentially passes through the scrubbing arm, the scrubbing head shaft, the scrubbing head and the scrubbing pad to supply polishing liquid or cleaning liquid or pure water to the back side of the wafer.

[0034] Optionally, the support assembly further includes a support head support shaft and a support fluid channel, wherein the support fluid channel sequentially passes through the support arm, the support head support shaft and the support head, and is connected to the support fluid nozzle to supply chemical liquid and / or pure water to the support fluid nozzle.

[0035] Optionally, the surface of the support head is circular, and the width of the gap between the surface of the support head and the front surface of the wafer is 0.3 to 2 mm.

[0036] Optionally, an annular guide portion is provided on the edge of the surface of the support head along the circumferential direction, the guide portion is made of a flexible material, and the distance between the upper edge of the guide portion and the front surface of the wafer is 0.1 to 1 mm;

[0037] The guide portion protrudes upward and outward in an arc shape from the edge of the surface of the support head and is retracted inward at the end, so that the supporting fluid forms a supporting fluid film on the front surface of the wafer.

[0038] Optionally, the wafer post-processing device also includes a supporting fluid pressure control component for controlling the flow rate and / or pressure of the supporting fluid so that the supporting force of the supporting fluid on the front side of the wafer is consistent with the scrubbing pressure when the scrubbing head is located at the edge of the wafer.

[0039] Optionally, the wafer post-processing device further includes a liquid supply component, which includes a cleaning liquid nozzle and a pure water nozzle for supplying cleaning liquid or pure water to the back side of the wafer.

[0040] Optionally, the trimming assembly includes a trimming table, a trimming piece, and a trimming piece cleaner;

[0041] The dressing table is rotatable, and the dressing member is mounted on an upper surface of the dressing table for contacting and dressing the scrubbing pad when the scrubbing head swings from the clamping assembly to above the dressing table;

[0042] The trimming piece cleaner is used to clean the trimming piece after trimming the scrubbing pad.

[0043] Optionally, the wafer post-processing device further includes a cleaning component, which is arranged on the route where the scrubbing head swings between the clamping component and the trimming component, and is used to spray cleaning liquid or pure water to clean the trimmed scrubbing pad.

[0044] A second aspect of the present invention provides a wafer backside scrubbing device, comprising: a scrubbing assembly, a supporting assembly, and a clamping assembly;

[0045] The scrubbing assembly includes a scrubbing arm, a scrubbing head, and a scrubbing pad, wherein the scrubbing head is arranged on the scrubbing arm, the scrubbing pad is arranged on the scrubbing head, and the scrubbing head drives the scrubbing pad to rotate;

[0046] The support assembly includes a support arm and a support head, wherein the support head is arranged on the support arm, and a plurality of support fluid spray holes are distributed on the surface of the support head;

[0047] When processing the wafer, the clamping assembly clamps and drives the wafer to rotate, and the wafer is located between the scrubbing pad and the supporting head. The scrubbing pad adheres to the back of the wafer with scrubbing pressure, and there is a gap between the supporting head and the front of the wafer. The scrubbing arm and the supporting arm swing, and during the swinging process, the scrubbing head and the supporting head are always opposite to each other, and the supporting fluid nozzle continuously sprays supporting fluid toward the front of the wafer, and the scrubbing pressure is not greater than the supporting force of the fluid on the front of the wafer.

[0048] A third aspect of the present invention provides a wafer backside scrubbing method, which uses the wafer post-processing device according to the first aspect or the wafer backside scrubbing device according to the second aspect to scrub the backside of the wafer, comprising:

[0049] Transferring the wafer to the clamping assembly, and controlling the clamping assembly to clamp the wafer;

[0050] Controlling the scrubbing arm to swing until the scrubbing head is located above the center of the wafer and the supporting head is located below the center of the wafer and opposite to the scrubbing head;

[0051] Controlling the scrubbing arm to descend until the scrubbing pad contacts the back of the wafer while controlling the supporting fluid to be ejected from the supporting fluid ejection hole;

[0052] The scrubbing fluid is supplied to the back side of the wafer, and at the same time, the scrubbing arm and the supporting arm are controlled to swing back and forth synchronously, the scrubbing head is controlled to rotate, and the clamping assembly is controlled to drive the wafer to rotate.

[0053] Optionally, the wafer backside scrubbing method further includes:

[0054] Controlling the scrubbing pressure so that when the scrubbing head is located at the center of the wafer, the center of the wafer has an upward warp of 0° to 2° relative to the edge of the wafer to prevent contaminants generated by scrubbing from accumulating on the back side of the wafer; and / or,

[0055] When the scrubbing head is located at the edge of the wafer, the wafer is level to prevent the clamping assembly from slipping.

[0056] Optionally, the wafer backside scrubbing method further includes:

[0057] When the scrubbing pressure when the scrubbing head is located at the edge of the wafer changes with the use of the scrubbing pad, the flow rate and / or pressure of the supporting fluid is controlled so that the supporting force of the supporting fluid on the front side of the wafer is consistent with the scrubbing pressure when the scrubbing head is located at the edge of the wafer.

[0058] Optionally, supplying scrubbing fluid to the back side of the wafer includes:

[0059] supplying polishing liquid to the back side of the wafer through the scrubbing fluid channel;

[0060] Stop supplying the polishing liquid and supplying the cleaning liquid to the back side of the wafer through the scrubbing fluid channel and the cleaning liquid nozzle;

[0061] Stop supplying the cleaning liquid and supply pure water to the back side of the wafer through the scrubbing fluid channel and the pure water nozzle;

[0062] stopping supplying pure water to the back side of the wafer through the scrubbing fluid channel;

[0063] The supply of pure water to the back side of the wafer through the pure water nozzle is stopped.

[0064] Optionally, supplying scrubbing fluid to the back side of the wafer includes:

[0065] supplying cleaning fluid to the back side of the wafer through the scrubbing fluid channel and the cleaning fluid nozzle;

[0066] Stop supplying the cleaning liquid and supply pure water to the back side of the wafer through the scrubbing fluid channel and the pure water nozzle;

[0067] stopping supplying pure water to the back side of the wafer through the scrubbing fluid channel;

[0068] The supply of pure water to the back side of the wafer through the pure water nozzle is stopped.

[0069] Optionally, the wafer backside scrubbing method further includes a dressing step for dressing the scrubbing pad, comprising:

[0070] Controlling the scrubbing arm to rise and swing until the scrubbing head is above the dressing table;

[0071] controlling the scrubbing arm to descend until the scrubbing pad is in contact with the trimming piece;

[0072] At least one of polishing liquid, cleaning liquid and pure water is supplied to the surface of the dressing piece, the scrubbing arm is controlled to swing back and forth, and the scrubbing head and the dressing table are controlled to rotate.

[0073] Optionally, controlling the scrubbing arm to rise and swing until the scrubbing head is located above the finishing table includes:

[0074] controlling the scrubbing arm and the supporting arm to stop swinging when they are located at the center of the wafer;

[0075] Controlling the scrubbing head to stop rotating and controlling the clamping assembly to stop driving the wafer to rotate;

[0076] controlling the scrubbing arm to rise while controlling the supporting fluid to stop spraying from the supporting fluid spray hole;

[0077] controlling the coupling mechanism to decouple;

[0078] The scrubbing arm is controlled to swing until the scrubbing head is located above the finishing table.

[0079] Optionally, the wafer backside scrubbing method further includes a cleaning step for cleaning the scrubbing pad after trimming, comprising:

[0080] Controlling the scrubbing arm to rise and swing until the scrubbing head is located above the cleaning assembly;

[0081] The cleaning component is controlled to spray cleaning liquid or pure water, and the scrubbing head is controlled to rotate.

[0082] Optionally, after the cleaning step, the scrubbing arm is kept stationary, the next wafer is transferred to the clamping assembly, and the clamping assembly is controlled to clamp the next wafer.

[0083] Optionally, controlling the support fluid to be ejected from the support fluid nozzle includes: controlling pure water and / or protective liquid to be ejected from the support fluid nozzle according to the surface film properties of the front side of the wafer;

[0084] A fourth aspect of the present invention provides a wafer processing device, comprising a controller and a wafer post-processing device as described in the first aspect, wherein the controller is used to control the wafer post-processing device to perform the wafer back side scrubbing method as described in the second aspect.

[0085] The present invention has the following technical effects: according to the wafer post-processing device, the back side scrubbing method and the processing equipment, the deep residue and chemical bonding residue on the back side of the wafer can be effectively removed by the scrubbing pad, and the micro defects on the back side of the wafer can be repaired, thereby improving the surface quality of the back side of the wafer; at the same time, by supporting the wafer in a non-contact manner, it can effectively avoid damaging the front side of the wafer, and can also form a fluid protective film on the front side of the wafer, reducing the difficulty of cleaning in subsequent processes, and finally producing wafers whose flatness and cleanliness of both the front and back surfaces meet the requirements of subsequent processes, thereby improving the yield rate of chip manufacturing. BRIEF DESCRIPTION OF THE DRAWINGS

[0086] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in the embodiments of the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0087] Figure 1 It is a structural schematic diagram of the polishing unit.

[0088] Figure 2 It is a structural schematic diagram of an embodiment of a wafer post-processing device of the present invention.

[0089] Figure 3 yes Figure 2 A schematic structural diagram of an embodiment of a support assembly of a wafer post-processing device.

[0090] Figure 4 yes Figure 2 A cross-sectional schematic diagram of an embodiment of a scrubbing assembly and a support assembly of a wafer post-processing apparatus.

[0091] Figure 5 It is a structural schematic diagram of an embodiment of a wafer post-processing device of the present invention.

[0092] Figure 6 It is a structural schematic diagram of an embodiment of a wafer post-processing device of the present invention.

[0093] Figure 7 It is a schematic flow chart of the wafer backside scrubbing method of the present invention.

[0094] Figure 8 It is a structural schematic diagram of an embodiment of the wafer processing equipment of the present invention.

[0095] Reference numerals:

[0096] Scrubbing assembly 1; scrubbing arm 11; scrubbing head 12; scrubbing pad 13; rotating lifting element 14; scrubbing fluid channel 15; scrubbing head shaft 16; scrubbing pressure control element 17;

[0097] Support assembly 2; support arm 21; support head 22; support fluid nozzle 221; guide portion 222; rotating element 24; support fluid channel 25; support head support shaft 26; fluid control assembly 27;

[0098] Clamping assembly 3; clamping element 31; first clamping element 311; second clamping element 312; third clamping element 313; fourth clamping element 314; first connecting mechanism 32; second connecting mechanism 33; connecting mechanism support element 34;

[0099] Cleaning component 4;

[0100] Liquid supply component 5; cleaning liquid nozzle 51; pure water nozzle 52;

[0101] Dressing assembly 6; dressing table 61; dressing piece 62; dressing piece cleaner 63;

[0102] Polishing head 10; polishing pad 20; polishing plate 30; polishing liquid supply device 40;

[0103] Wafer post-processing device 100; controller 200;

[0104] Wafer processing equipment 1000. DETAILED DESCRIPTION

[0105] In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by those skilled in the art based on the embodiments in the embodiments of the present invention should fall within the scope of protection of the embodiments of the present invention.

[0106] In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0107] In addition, in the description of the present invention, unless otherwise specified and limited, it should be noted that the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a mechanical connection or an electrical connection, or it can be the internal connection between two components. It can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to the specific circumstances.

[0108] In the CMP equipment, the wafer will pass through the polishing unit, scrubbing unit, cleaning unit and drying unit in sequence to perform polishing, cleaning, drying and other processing processes on the wafer.

[0109] Figure 1 This is a schematic diagram of a polishing unit. As shown in the figure, the polishing pad 20 covers the upper surface of the polishing disk 30, the polishing liquid supply device 40 spreads the polishing liquid on the surface of the polishing pad 20, and the polishing head 10 adsorbs the front side of the wafer facing down and presses it against the polishing pad 20 with polishing pressure. During polishing, the polishing head continuously applies pressure to the back side of the wafer and drives the wafer to rotate and move to complete the removal of the material on the front side of the wafer under chemical and mechanical effects. However, the back side of the wafer may be contaminated before polishing, and contaminants generated during the polishing process may remain in the polishing head. Particles in these particles may be embedded in the back side of the wafer under the action of mechanical pressure, forming deep residues. Some contaminants, such as some metal oxides or organic compounds, will react with the material on the back side of the wafer to form chemically bonded residues under the combined effects of high pressure, high temperature, and strong acid and strong base chemical environments during polishing.

[0110] After polishing, the wafers are transferred to the scrubbing unit and the cleaning unit for cleaning. However, both the roller brush cleaning in the scrubbing unit and the high-pressure nozzle cleaning in the cleaning unit can only remove contaminants on the wafer surface, such as residual dust particles, inorganic matter, or metal ions adsorbed by electrostatic effects. They cannot completely remove deep residues embedded in the back of the wafer, and are completely helpless against chemically bonded residues. In addition, microscopic defects may exist on the back of the polished wafer, including scratches generated during wafer processing and pits formed by the detachment of particles embedded in the back of the wafer. Existing CMP equipment is obviously unable to improve these microscopic defects. As a result, wafers with deep residues, chemically bonded residues, or microscopic defects on the back are transferred to subsequent process steps, and as the process node increases, the wafer yield rate is increasingly adversely affected. For example, in the photolithography process of processes below 7nm, contaminants on the bottom of the wafer can cause local unevenness on the wafer surface, resulting in local unevenness when applying the glue, causing defects such as chucking spots and focus spots after exposure, reducing the yield rate of chip manufacturing.

[0111] The present invention provides a wafer post-processing device for performing back-side processing on a polished wafer to improve the quality of the back side of the wafer and solve the above-mentioned technical problems.

[0112] Figure 2 FIG. 1 is a schematic diagram of an embodiment of a wafer post-processing device 100 of the present invention. As shown in the figure, the wafer post-processing device 100 includes: a scrubbing assembly 1 , a supporting assembly 2 , and a clamping assembly 3 .

[0113] The scrubbing assembly 1 includes a scrubbing arm 11, a scrubbing head 12, a scrubbing pad 13, and a scrubbing fluid channel 15. The scrubbing arm 11 is arranged and extended horizontally, and the scrubbing head 12 is arranged downward on the scrubbing arm 11. The scrubbing arm 11 can drive the scrubbing head 12 to swing back and forth around a fixed axis. The scrubbing pad 13 is provided on the surface of the scrubbing head 12 away from the scrubbing arm 11. The scrubbing head 12 can rotate and drive the scrubbing pad 13 to rotate together when rotating. The scrubbing fluid channel 15 is used to supply scrubbing fluid to the back side of the wafer to form a chemical environment between the scrubbing pad and the back side of the wafer that is easy to scrub. As can be seen, the scrubbing assembly 1 simulates the chemical mechanical polishing process by pressing the scrubbing pad 13 against the back side of the wafer, which is distributed with chemical liquid, at a predetermined scrubbing pressure and swinging and rotating back and forth. This removes a small amount of material layer on the back side of the wafer while achieving the purpose of removing deep residues and chemical bonding residues. At the same time, it can also repair microscopic defects and improve the surface quality of the back side of the wafer.

[0114] However, the wafer post-processing device 100 processes polished wafers, that is, the front side of the wafer has reached a predetermined flatness. In addition, when CMP is used for advanced packaging, the front side of the wafer may also have specific structures such as through-silicon vias (TSVs) and metal wiring. In order to ensure the scrubbing effect and scrubbing efficiency, the scrubbing pressure applied by the scrubbing pad on the back side of the wafer cannot be too low. The typical scrubbing pressure is 0.3 to 3 psi (pounds per square inch) or 1 / 4 to 1 / 2 of the corresponding polishing pressure in the polishing unit. In order to prevent the scrubbing pressure from causing wafer fragments, corresponding support needs to be formed on the front side of the wafer. If the front side of the wafer is supported by contacting the wafer, the reaction force of the support may damage the specific structure on the front side of the wafer and destroy the flatness of the front side of the wafer.

[0115] The support assembly 2 includes a support arm 21 and a support head 22. The support arm 21 is arranged and extended horizontally, and the support head 22 is arranged upward on the support arm 21. The support arm 21 can drive the support head 22 to swing around a fixed axis. A plurality of support fluid nozzles 221 are distributed on the surface of the support head 22 away from the support arm 21. The clamping assembly 3 can clamp the wafer and drive the wafer to rotate. When processing the wafer, the clamping assembly 3 clamps the wafer horizontally to fix the wafer at a predetermined height. The support head 22 and the scrubbing head 12 are aligned with each other across the wafer. The support head 22 does not contact the front of the wafer. The support fluid is sprayed onto the front of the wafer through the plurality of support fluid nozzles 221, thereby forming a support force to lift the wafer in the gap between the support head 22 and the front of the wafer. Ensure that when the scrubbing pad applies appropriate scrubbing pressure, it will not damage the characteristic structure of the front of the wafer, nor will it destroy the flatness of the front of the wafer.

[0116] Optionally, the clamping assembly 3 includes at least three spaced-apart clamping elements 31. The clamping elements 31 have the same height and can move horizontally relative to each other to move closer or further away, thereby clamping the wafer when approaching and releasing the wafer when moving away. The clamping elements 31 are preferably wheeled, and at least one of the clamping elements 31 is used to drive the wafer in rotation.

[0117] When scrubbing the back side of the wafer, the wafer is horizontally clamped between the scrubbing pad 13 and the supporting head 22 by the clamping assembly 3, with the front side of the wafer facing downwards and facing the supporting head. While the scrubbing pad 13 is pressed against the back side of the wafer with a certain scrubbing pressure, the supporting head 22 continuously sprays a supporting fluid toward the front side of the wafer. During the scrubbing process, the scrubbing fluid channel 15 supplies scrubbing fluid to the back side of the wafer, the clamping element 31 drives the wafer to rotate, the scrubbing head 12 drives the scrubbing pad 13 to rotate, and the scrubbing arm 11 and the supporting arm 21 synchronously drive the scrubbing head 12 and the supporting head 22 to swing back and forth, and the scrubbing head 12 and the supporting head 22 always maintain alignment during the swinging process. Thus, under the combined action of the scrubbing pad and the scrubbing fluid, the back side material of the wafer is removed in small amounts, and the deep residue and chemical bond residue on the back side of the wafer are also removed together. In addition, the microscopic defects on the back side of the wafer are also repaired in the process of removing the back side material. At the same time, since the supporting head 22 does not directly contact the front side of the wafer, contact damage to the front side of the wafer is avoided. In summary, the wafer post-processing device of this embodiment ensures that both the front and back sides of the wafer have good surface quality, thereby improving the yield rate of wafer processing and chip manufacturing.

[0118] In one embodiment, Figure 3 or Figure 4 As shown, the scrubbing assembly 1 also includes a scrubbing head shaft 16, which connects the scrubbing arm 11 and the scrubbing head 12. A scrubbing fluid channel 15 extends sequentially along the scrubbing arm 11, the scrubbing head shaft 16, and the scrubbing head 12 to a central through-hole in the scrubbing pad 13, thereby supplying a polishing liquid, a cleaning liquid, or pure water (DIW) to the backside of the wafer. Optionally, at least two of the polishing liquid, the cleaning liquid, or the pure water are supplied to the backside of the wafer in a predetermined sequence.

[0119] The support assembly 2 includes a support fluid channel 25 and a support head support shaft 26. The support fluid channel 25 passes through the support arm 21, the support head support shaft 26 and the support head 22 in sequence to the support fluid nozzle 221 to supply at least one of gas, pure water or chemical liquid to the support fluid nozzle 221.

[0120] Optionally, the contact surfaces of the scrubbing head 12 and the support head 22 with the wafer are circular and of equal size, and the scrubbing head 12 and the support head 22 are aligned, that is, each is aligned with the center of the contact surface of the wafer. The scrubbing fluid is directly supplied between the wafer and the scrubbing pad 13 through the scrubbing fluid channel 15, which helps to reduce the amount of scrubbing fluid used while ensuring uniform distribution of the scrubbing fluid, thereby improving the efficiency and uniformity of removing the material layer on the back of the wafer.

[0121] Optionally, the supporting fluid nozzles 221 are evenly distributed on the surface of the support head 22 to form a uniform supporting fluid layer between the support head 22 and the wafer front surface. The width of the gap between the support head 22 and the wafer front surface is 0.3 to 2 mm, preferably 0.5 to 1 mm, to facilitate fluid pressure maintenance and thus reduce supporting fluid consumption. It also prevents slight vibration and deformation of the wafer during the scrubbing process from contacting the support head 22 and damaging the wafer front surface.

[0122] Optionally, an upwardly protruding annular flow guide 222 is provided along the circumferential edge of the surface of the support head 22. The flow guide 222 is made of a flexible material such as silicone rubber or polyurethane. The distance between the upper edge of the flow guide 222 and the front surface of the wafer is 0.1 to 1 mm, preferably 0.2 to 0.5 mm. This can further improve the fluid pressure maintenance effect without worrying about damaging the front surface of the wafer.

[0123] Optional, such as Figure 4 As shown, the cross section of the guide portion 222 is arc-shaped, and the arc-shaped cross section has a shape that protrudes upward and outward along the radial direction of the support head 22, and is retracted inward at the end, so that the supporting fluid has a flow trend as shown by the arrow in the figure when overflowing from the guide portion 222. This further improves the fluid pressure maintenance effect and forms a layer of supporting fluid film on the front side of the wafer. The supporting fluid film not only serves as a protective film to prevent the front side of the wafer from crystallizing or drying up due to water evaporation, but also prevents pollutants discharged from the back side of the wafer during the scrubbing process and pollutants in the atmosphere from adhering to the front side of the wafer, thereby reducing the difficulty of cleaning in subsequent processes.

[0124] In one embodiment, Figure 1 As shown, the scrubbing assembly 1 also includes a rotating lifting element 14 with rotating and lifting functions and a scrubbing pressure control element 17. The rotating lifting element 14 is connected to one end of the scrubbing arm 11, and drives the scrubbing arm 11 to swing and lift by rotating and lifting. The scrubbing head 12 is arranged at the other end of the scrubbing arm 11 away from the rotating lifting element 14. The rotating lifting element 14 adjusts the height of the scrubbing head 12 by lifting and lowering, so that the scrubbing pad 13 can press against and separate from the back of the wafer, and when pressing against the back of the wafer, the scrubbing pressure applied to the back of the wafer by the scrubbing pad 13 is further adjusted under the control of the scrubbing pressure control element 17. When the wafer post-processing device 100 processes the wafer, the scrubbing head 12 swings back and forth between the center and the edge of the wafer. The scrubbing swing route of the scrubbing head 12 is shown as follows. Figure 5As shown, it is understood that the swing path of the support head 22 is the same as the swing path of the scrubbing head 12. As the rotary lifting element 14 rotates, it adjusts the scrubbing pressure applied by the scrubbing pad 13 to the back of the wafer according to the position of the scrubbing head 12. In other words, the scrubbing head 12 can apply different scrubbing pressures to the wafer at different positions on the wafer, causing the wafer to deform during the scrubbing process, thereby improving the scrubbing effect on the back of the wafer.

[0125] Optionally, when the scrubbing head 12 is located at the center of the wafer, the scrubbing pressure is less than the supporting force of the supporting fluid on the wafer, so that the center of the wafer has an upward warp of 0 ° to 2 ° relative to the edge of the wafer. The upward warp of the slight angle will not damage the wafer, but will help guide the pollutants to flow to the edge of the wafer along the curved surface formed by the upward warp and be discharged from the edge of the wafer, thereby preventing the pollutants generated by scrubbing from accumulating on the back side of the wafer and damaging the back side of the wafer. Particularly in the part where the scrubbing pad 13 contacts the back side of the wafer, a tiny gap will also be generated due to the continuous, slight angle warp of the wafer. Under the action of the scrubbing fluid, the scrubbing byproducts therein can be taken out and discharged from between the scrubbing pad 13 and the back side of the wafer, avoiding the risk of damage to the back side of the wafer and also extending the service life of the scrubbing pad 13 to a certain extent.

[0126] When the scrubbing head 12 is positioned at the edge of the wafer, the scrubbing fluid on the back of the wafer and the supporting fluid on the front of the wafer cause the space between the clamping assembly 3 and the wafer edge to be filled with fluid. If the wafer edge is deformed, the clamping assembly 3 may slip, thereby affecting the wafer scrubbing effect. Therefore, when the scrubbing head 12 swings from the center of the wafer to the edge of the wafer, adjusting the scrubbing pressure to keep the wafer horizontal can prevent the clamping assembly 3 from slipping.

[0127] The scrubbing pressure control element 17 can adjust the scrubbing pressure continuously or discontinuously, which is not limited here. Those skilled in the art will appreciate that by adjusting the pressure applied by the scrubbing pad 13 to the back of the wafer at the center and at the edge of the wafer, the wafer can be deformed differently, thereby facilitating the removal of contaminants while preventing slippage that affects the scrubbing effect.

[0128] In one embodiment, Figure 5As shown, the wafer post-processing apparatus 100 further includes a fluid control assembly 27 for controlling the flow rate and pressure of the support fluid ejected from the support fluid nozzles 221. Optionally, the fluid control assembly 27 synchronizes the changes in the scrubbing pressure of the scrubbing head at the wafer edge in a preset scrubbing recipe and maintains consistency between the two. In particular, when the scrubbing pressure in the scrubbing recipe is set to change with the use of the scrubbing pad 13, for example, if the scrubbing pad 13 deteriorates due to use and the scrubbing pressure needs to be increased to ensure a good scrubbing effect, the fluid control assembly 27 adjusts the flow rate and pressure of the support fluid so that the supporting force generated by the support fluid increases synchronously.

[0129] In one embodiment, the support assembly 2 includes a rotating element 24 with a rotating function. The rotating element 24 is connected to one end of the support arm 21 and drives the support arm 21 to swing by rotating. The support head 22 is located at the other end away from the rotating element 24. The rotating lifting element 14 and the rotating element 24 are coaxially arranged, and the scrubbing arm 11 and the support arm 21 have the same length, thereby ensuring that the scrubbing head 12 and the support head 22 swing synchronously and are always relative to each other during scrubbing.

[0130] Optionally, the shapes of the scrubbing assembly 1 and the support assembly 2 are basically the same, that is, the rotating lifting element 14 and the rotating element 24 are symmetrically arranged, the scrubbing arm 11 and the support arm 21 are symmetrically arranged, and there is space between the scrubbing arm 11 and the support arm 21 to accommodate the relative scrubbing heads 12 and support heads 22, the scrubbing head rotating shaft 16 and the support head support shaft 26, the scrubbing pad 13, and the gap between the surface of the wafer and the support head 22 and the front side of the wafer, thereby maintaining the stability of the overall structure and accurate control, thereby improving the scrubbing effect.

[0131] In one embodiment, Figure 1 or Figure 5 As shown, the clamping assembly 3 includes four equally spaced clamping elements 31. The four clamping elements 31 are divided into two groups: the first group comprises a first clamping element 311 and a second clamping element 312, which are connected by a first connecting mechanism 32; the second group comprises a third clamping element 313 and a fourth clamping element 314, which are connected by a second connecting mechanism 33. The first connecting mechanism 32 and the second connecting mechanism 33 are movable relative to each other in the horizontal direction to move the four clamping elements 31 closer to or further away from each other. Furthermore, the first connecting mechanism 32 or the second connecting mechanism 33 is configured so as not to interfere with the scrubbing assembly 1 or the support assembly 2 during movement.

[0132] The first clamping element 311 and the second clamping element 312 are respectively mounted at the two ends of the first connecting mechanism 32, and the third clamping element 313 and the fourth clamping element 314 are respectively mounted at the two ends of the second connecting mechanism 33. The line connecting the first clamping element 311 and the second clamping element 312 is parallel to the line connecting the third clamping element 313 and the fourth clamping element 314 to ensure stable clamping. However, this will inevitably cause at least one coupling mechanism and at least one clamping element to overlap with the swing path of the scrubbing arm 11, scrubbing head 12, and support arm 21, thereby interfering with the movement. In this embodiment, interference is prevented by setting the horizontal and vertical positions of the coupling mechanism and the clamping elements.

[0133] Alternatively, the scrubbing assembly 1, the supporting assembly 2, and the clamping assembly 3 are positioned so that only the first connecting mechanism 32 and the first clamping element 311 overlap horizontally with the swing path of the supporting arm 21, while no other parts overlap horizontally. Furthermore, the first clamping element 311 and the first connecting mechanism 32 are positioned vertically between the scrubbing arm 11 and the supporting arm 21 so as not to interfere with the swinging scrubbing arm 11 and the supporting arm 21.

[0134] Optionally, the first connecting mechanism 32 is a U-shaped plate with an opening facing the wafer. The first clamping element 311 and the second clamping element 312 are respectively fixed to the two ends of the upper surface of the first connecting mechanism 32. The connecting mechanism support element 34 is connected to the lower surface of the first connecting mechanism 32 to provide support therefor, and the connecting mechanism support element 34 is opposite the second clamping element 312. Similarly, only the first connecting mechanism 32 and the first clamping element 311 overlap with the swing path of the support arm 21 in the horizontal direction, so the second clamping element 312 and the connecting mechanism support element 34 do not overlap with the swing path of the support arm 21. The connecting mechanism support element 34 serves as a supporting structure for the first connecting mechanism 32, so that the first clamping element 311 and the first connecting mechanism 32 are vertically located between the scrubbing arm 11 and the support arm 21, thereby preventing interference with the swinging scrubbing arm 11 and the support arm 21. Preferably, the connecting mechanism support element 34 is movable horizontally to drive the first connecting mechanism 32 to move horizontally relative to the second connecting mechanism 33.

[0135] Optionally, the second connecting mechanism 33 is a straight plate, and the third clamping element 313 and the fourth clamping element 314 are respectively fixed to the two ends of the upper surface of the second connecting mechanism 33. The rotating element 24, the second connecting mechanism 33, and the connecting mechanism support element 34 are all connected to the chamber base of the wafer post-processing device 100. The four clamping elements 31 are configured to have the same clamping height to ensure horizontal clamping of the wafer. The second connecting mechanism 33 is configured to be farther away from the rotating lifting element 14 than the first connecting mechanism 32, so that the second connecting mechanism 33, the third clamping element 313, and the fourth clamping element 314 can be easily prevented from interfering with the scrubbing arm 11, the scrubbing head 12, or the support arm 21.

[0136] Preferably, all four clamping elements 31 have active wheels for driving the wafer rotation, or, alternatively, only the first clamping element 311 has a driven wheel while the other three clamping elements all have active wheels. This provides a more stable friction force and driving torque for wafer rotation, preventing the wafer rotation speed from being disturbed by the friction torque of the scrubbing pad and affecting the stability of the wafer rotation speed, thereby ensuring uniform scrubbing of the wafer backside. According to the wafer post-processing device 100 of this embodiment, the wafer is stably clamped and rotated, and the scrubbing head does not interfere with the clamping mechanism during its swinging process, making the overall structure compact and highly space-efficient.

[0137] In one embodiment, Figure 5 As shown, wafer post-processing apparatus 100 further includes a liquid supply assembly 5, which includes a cleaning liquid nozzle 51 and a pure water nozzle 52 for supplying cleaning liquid or pure water to the backside of the wafer. Optionally, second connecting mechanism 33 is fixed to the base, and liquid supply assembly 5 is disposed on the second coupling mechanism. The cleaning liquid nozzle 51 and pure water nozzle 52 are rotatable L-shaped nozzles.

[0138] According to the wafer post-processing device 100 of this embodiment, polishing liquid is supplied to the back side of the wafer through the scrubbing fluid channel 15, and cleaning liquid or pure water can be supplied to the back side of the wafer through the scrubbing fluid channel 15 and the liquid supply component 5 at the same time, so as to prevent the limited amount of liquid under the scrubbing pad due to the small area of the scrubbing pad, and prevent sufficient liquid from being provided when scrubbing a wafer that is much larger than the area of the scrubbing pad, thereby affecting the scrubbing effect and scrubbing efficiency.

[0139] As scrubbing progresses, the surface of the scrubbing pad deteriorates, affecting the scrubbing effect.

[0140] In one embodiment, Figure 5 and Figure 6 As shown, the wafer post-processing apparatus 100 further includes a trimming assembly 6. The trimming assembly 6 is located at one end of the trimming swing path of the scrubbing head 12. The scrubbing arm 11 can swing the scrubbing head 12 to a suitable position of the trimming assembly, so that the trimming assembly 6 can trim the surface of the scrubbing pad to a state suitable for scrubbing.

[0141] Optionally, the dressing assembly 6 includes a dressing table 61, a dressing piece 62, and a dressing piece cleaner 63. The dressing table 61 is rotatable, and the dressing piece 62 is mounted on the upper surface of the dressing table 61 and rotates with the dressing table. The dressing piece 62 can be, for example, a diamond disk. When the scrubbing head 12 swings from the clamping assembly 3 to above the dressing table 61, it contacts and trims the scrubbing pad 13, thereby trimming the surface of the scrubbing pad to a state suitable for scrubbing. After the trimming is completed, the surface of the trimming piece 62 may contain trimming byproducts generated during the trimming process. The trimming piece cleaner 63 sprays cleaning fluid or pure water to clean the trimming piece 62, thereby preventing the trimming byproducts from affecting the subsequent trimming effect.

[0142] As shown in the figure, in order to allow the limited length of the scrubbing arm 11 to swing to the trimming assembly 6, the trimming assembly 6 is placed close to the space where the wafer is clamped by the clamping assembly 3. This results in contaminants generated during the scrubbing process being splashed onto the trimming assembly 6, which may also form crystals and break off, damaging the wafer.

[0143] Therefore, the scrubbing arm 11 is configured to cause the scrubbing head 12 to oscillate back and forth between the center of the wafer and the edge of the wafer away from the trimming assembly 6. In other words, the scrubbing and trimming oscillation paths of the scrubbing head 12 do not overlap, thereby preventing contaminants generated by scrubbing from splashing onto the trimming assembly. Simultaneously, while the wafer is being processed, the trimming cleaning device 63 can continuously spray a small amount of pure water to prevent crystallization through a moisturizing effect.

[0144] Optionally, the rotary lifting element 14 includes a rotary motor and a coupling mechanism (not shown). The coupling mechanism is coupled so that rotation of the rotary motor drives both the rotary lifting element 14 and the rotary element 24 to rotate synchronously. The coupling mechanism is decoupled so that rotation of the rotary motor drives only the rotary lifting element 14. That is, during wafer processing, the coupling mechanism is coupled so that rotation of the rotary motor drives both the rotary lifting element 14 and the rotary element 24 to rotate synchronously, ensuring synchronized rotation of the scrubbing arm 11 and the support arm 21, thereby maintaining the scrubbing head 12 and the support head 22 in relative orientation. During trimming of the scrubbing pad, the coupling mechanism is decoupled so that rotation of the rotary motor drives only the rotary lifting element 14, while the rotary element 24 does not rotate. This keeps the support assembly 2 stationary, while the scrubbing arm 11 drives the scrubbing head 12 to the trimming assembly 6. Sharing a single motor not only ensures synchronous rotation but also reduces the risk of motor damage from contamination and corrosion in the highly corrosive CMP environment. It also reduces the risk of contaminants such as metal ions generated by the motor's rotation that could contaminate the wafers.

[0145] In one embodiment, Figure 6As shown, the wafer post-processing device 100 also includes a cleaning component 4, which is arranged between the clamping component 3 and the trimming component 6 and is located on the trimming swing path. The surface of the scrubbing pad 13 after trimming may be adhered to particles of the scrubbing pad, polishing liquid, trimming parts, etc., which may affect the subsequent scrubbing effect. When the scrubbing head 12 swings over the cleaning component 4, the cleaning component 4 sprays cleaning liquid or pure water to clean the surface of the scrubbing pad 13. Optionally, the cleaning component 4 is a fan-shaped nozzle or a solid cone nozzle, and the cleaning component 4 is connected to the liquid supply component 5.

[0146] According to the wafer post-processing device 100 of the present invention, a trimming component for automatically trimming the scrubbing pad and a cleaning component for cleaning the scrubbing pad are integrated, which effectively ensures the post-processing effect of the wafer and improves the yield rate of chip manufacturing; at the same time, it increases the service life of the scrubbing pad and the trimming parts and saves costs.

[0147] The present invention also provides a wafer backside scrubbing method using the wafer post-processing apparatus 100 , which is used to scrub and rinse deep residues and chemical bonding residues on the backside of the wafer.

[0148] In one embodiment, Figure 7 As shown, the following steps are included:

[0149] S1. Transfer the wafer to the clamping assembly 3 and control the clamping assembly 3 to clamp the wafer.

[0150] Alternatively, the transfer can be performed by a transfer robot. Before the transfer, the scrubbing head 12 is outside the clamping range of the clamping assembly 3 so as not to affect the transfer and clamping. After the transfer robot clamps the wafer and stops at a predetermined position, the clamping elements 31 of the clamping assembly 3 move closer to each other to clamp the wafer.

[0151] S2 . Control the scrubbing arm 11 to swing to a predetermined position where the scrubbing head 12 is located above the wafer. The predetermined position makes the scrubbing head 12 face the supporting head 22 .

[0152] Optionally, the support head 22 stops at a position facing the center of the front side of the wafer, and the scrubbing arm 11 is controlled to swing to a position where the scrubbing head 12 faces the center of the back side of the wafer.

[0153] S3 . Control the scrubbing arm 11 to press down until the scrubbing pad 13 contacts the back of the wafer, and control the supporting fluid to be sprayed out from the supporting fluid spray hole 221 .

[0154] Optionally, the flow rate and pressure of the fluid ejected from the supporting fluid nozzles 221 are controlled so that the fluid pressure supporting the front surface of the wafer is initially low and gradually increases as the scrubbing head 12 moves downward, thereby preventing excessive pressure on any one side of the wafer from causing chipping. After scrubbing is completed, as the scrubbing head 12 rises and separates from the wafer, the flow rate and pressure of the fluid ejected from the supporting fluid nozzles 221 are controlled in the opposite manner.

[0155] S4. Supply scrubbing fluid to the back of the wafer, and at the same time control the scrubbing arm 11 and the support arm 21 to swing back and forth synchronously, and control the scrubbing head 12 and the clamping assembly 3 to drive the wafer to rotate.

[0156] During the scrubbing process, the wafer and scrub head 12 rotate in the same direction, but at different speeds. The scrubbing arm 11 drives the scrubbing head 12 to swing back and forth along the wafer's radial direction, while the support arm 21 also drives the support head 22 to swing synchronously, keeping the scrubbing head 12 and the support head 22 facing each other at all times. Simultaneously, scrubbing fluid is supplied to the back of the wafer as needed to remove deep residue and chemical bonding residue on the back of the wafer without damaging the front of the wafer.

[0157] Optionally, controlling the support fluid to be ejected from the support fluid ejection hole in step S3 further includes controlling the type of the support fluid according to the surface film properties of the front side of the wafer, specifically including:

[0158] For the surface film layer on the front side of the wafer that is hydrophilic and has a low risk of corrosion from pure water, the pure water is controlled to be ejected from the supporting fluid nozzle;

[0159] For the surface film layer with hydrophobic properties or high risk of corrosion from pure water on the front side of the wafer, the protective liquid is controlled to be sprayed from the support fluid nozzle;

[0160] For surface films with a medium risk of corrosion when exposed to pure water, the protective liquid and pure water are controlled to be sprayed alternately from the supporting fluid nozzles.

[0161] The protective solution includes at least one of a specific pH value, an antioxidant-added protective solution to prevent localized electrochemical corrosion of the metal interconnect layer, and a trace amount of surfactant added to reduce surface tension. This embodiment provides specialized protection for wafer front surfaces with varying surface film properties while reducing the cost of the protective solution.

[0162] Optionally, by controlling the specific order of supplying scrubbing fluid to the back side of the wafer in step S4, the scrubbing effect can be further improved, and the back side of the wafer can be rinsed at the same time to improve the cleaning efficiency in subsequent processes, which specifically includes the following steps:

[0163] S411. Polishing liquid is supplied to the back of the wafer through the scrubbing fluid channel 15. The polishing liquid is used to accelerate the removal of a small amount of material layer on the back of the wafer, thereby facilitating the rapid and thorough removal of deep residues and chemical bonding residues.

[0164] S412: The polishing liquid supply is stopped, and cleaning liquid is supplied to the back side of the wafer through the scrubbing fluid channel 15 and the cleaning liquid nozzle 51. The cleaning liquid helps to enhance the cleaning effect, thereby quickly removing and discharging contaminant particles. At the same time, the cleaning liquid nozzle 51 can increase the amount of cleaning liquid supplied and provide a flushing effect, thereby preventing contaminants from re-attaching to the back side of the wafer during the movement of the scrubbing pad 13.

[0165] S413: Stop supplying the cleaning fluid and supply pure water to the back of the wafer through the scrubbing fluid channel 15 and the pure water nozzle 52. Optionally, the flow rate and pressure of the pure water are much greater than those of the cleaning fluid, thereby providing a better rinsing effect and removing all residual contaminant particles, polishing fluid, and cleaning fluid on the back of the wafer.

[0166] S414. Stop supplying pure water to the back of the wafer through the scrubbing fluid channel 15. After stopping the water supply, control the scrubbing arm 11 to rise to a predetermined height, and control the scrubbing arm 11 to swing until the scrubbing head 12 leaves the wafer.

[0167] S415. Stop supplying pure water to the back of the wafer through the pure water nozzle 52. While the scrubbing head 12 is away from the wafer, pure water is continuously supplied to the back of the wafer through the pure water nozzle 52 to rinse away the residual contaminants under the scrubbing pad 13 and the contaminants dripping from the scrubbing head 12.

[0168] In one embodiment, polishing liquid may not be used when supplying scrubbing fluid to the back side of the wafer in step S4, thereby reducing the use of polishing liquid and the resulting pollution. However, the scrubbing time may be appropriately increased to remove the material layer on the back side of the wafer primarily through mechanical action, including the following steps:

[0169] S421. Supply cleaning fluid to the back of the wafer through the scrubbing fluid channel 15 and the cleaning fluid nozzle 51;

[0170] S422 stops supplying cleaning fluid and supplies pure water to the back of the wafer through the scrubbing fluid channel 15 and the pure water nozzle 52;

[0171] S423. Stop supplying pure water to the back of the wafer through the scrubbing fluid channel 15;

[0172] S424. Stop supplying pure water to the back side of the wafer through the pure water nozzle 52.

[0173] Compared with using a roller brush for cleaning in a scrubbing unit, this embodiment can apply greater scrubbing pressure to the wafer to remove part of the material layer on the back of the wafer, effectively improving deep residues, chemical bonding residues or microscopic defects without causing damage to the front of the wafer, while also reducing the increased cost and increased contamination risk caused by the use of polishing fluid.

[0174] In one embodiment, the wafer backside scrubbing method of the present invention further comprises the following steps:

[0175] S5. Control the scrubbing pressure so that when the scrubbing head is located at the center of the wafer, the center of the wafer has an upward warp of 0° to 2° relative to the edge of the wafer to prevent contaminants generated by scrubbing from accumulating on the back of the wafer;

[0176] And when the scrubbing head is located at the edge of the wafer, the wafer is in a horizontal state to prevent the clamping component from slipping.

[0177] Optionally, when the scrubbing head 12 and the supporting head 22 are at the center of the wafer, the scrubbing pressure, the pressure and the flow of the supporting fluid are controlled to increase synchronously, and the scrubbing pressure is maintained after reaching the scrubbing pressure in the scrubbing formula, and the supporting force of the supporting fluid is continued to increase to be greater than the scrubbing pressure until the center of the wafer has an upward warp of 0° to 2° relative to the edge of the wafer. During the swinging process of the scrubbing head 12, the supporting force of the supporting fluid is kept unchanged, and the scrubbing pressure applied to the wafer by the scrubbing head 12 is periodically controlled: during the swinging process of the scrubbing head 12 from the center of the wafer to the edge of the wafer, the scrubbing pressure gradually increases, and when the scrubbing head 12 is located at the edge of the wafer, the wafer is in a horizontal state; and during the swinging process of the scrubbing head 12 from the edge of the wafer to the center of the wafer, the scrubbing pressure gradually decreases, so that when the scrubbing head 12 is located at the center of the wafer, the supporting force of the supporting fluid again pushes the center of the wafer upward relative to the edge of the wafer to have an upward warp of 0° to 2°.

[0178] It can be seen that this embodiment can effectively prevent the contaminants generated by scrubbing from accumulating on the back of the wafer by controlling the scrubbing pressure applied by the scrubbing head to the back of the wafer, so that the contaminants will not affect the scrubbing effect; and avoid the clamping component slipping when clamping the wafer and affecting the scrubbing effect.

[0179] In one embodiment, as the scrubbing pad is used, the scrubbing pressure may need to be changed to maintain the scrubbing effect. For example, if the scrubbing pad deteriorates due to use, the scrubbing pressure may need to be increased. The wafer backside scrubbing method of the present invention further includes the following steps:

[0180] S6. When changing the scrubbing pressure according to scrubbing needs, control the flow rate and pressure of the supporting fluid supplied to the supporting fluid nozzle so that the supporting force formed by the supporting fluid is consistent with the scrubbing pressure when the scrubbing head is at the edge of the wafer.

[0181] It can be seen that this embodiment synchronously controls the flow rate and pressure of the supply supporting fluid, so that during the continuous production process, even if the scrubbing pressure changes, the periodic micro-deformation of the wafer can still be maintained to ensure the scrubbing effect of the scrubbing method of the present invention.

[0182] In one embodiment, the scrubbing method of the present invention further includes a scrubbing pad conditioning step S7 for conditioning the scrubbing pad 13 after processing the wafer to a state suitable for scrubbing, comprising:

[0183] S71 . Control the scrubbing arm 11 to rise and swing until the scrubbing head 12 is located above the finishing table 61 .

[0184] S72 . Control the scrubbing arm 11 to descend until the scrubbing pad 13 is in contact with the trimming piece 62 .

[0185] S73. Supply at least one of polishing liquid, cleaning liquid and pure water to the surface of the dressing member 62, control the scrubbing arm 11 to swing back and forth, and control the scrubbing head 12 and the dressing table 61 to rotate.

[0186] Optionally, step S71 includes the following steps:

[0187] S711 control scrubbing arm 11 and support arm 21 stop swinging when located at the center of the wafer;

[0188] S712 controls the scrubbing head 12 to stop rotating and controls the clamping assembly 3 to stop driving the wafer to rotate;

[0189] S713. Control the scrubbing fluid to stop spraying from the supporting fluid nozzle 221 and control the scrubbing arm 11 to rise;

[0190] S714. Control coupling mechanism decoupling;

[0191] S715 . Control the scrubbing arm 11 to swing until the scrubbing head 12 is located above the finishing table 61 .

[0192] In one embodiment, the wafer backside scrubbing method of the present invention further includes a scrubbing pad cleaning step S8 for cleaning the trimmed scrubbing pad 13, specifically comprising:

[0193] S81. After finishing the scrubbing pad 13, the scrubbing arm 11 is controlled to rise and swing until the scrubbing head 12 is located above the cleaning assembly 4, and the cleaning assembly 4 is located on the trimming swing path between the clamping assembly 3 and the trimming assembly 6.

[0194] S82. Control the cleaning component 4 to spray cleaning liquid or pure water, and control the scrubbing head 12 to rotate, so as to flush away various pollutant particles attached to the scrubbing pad 13 during the trimming step through the liquid.

[0195] At the same time, the trimming piece washer 63 starts to clean and moisturize the trimming piece 62 to wash away various pollutant particles attached to the trimming piece 62 during the trimming step and prevent crystallization due to water evaporation.

[0196] In one embodiment, wafers are transferred to the wafer post-processing apparatus 100 according to the production cycle. After scrubbing and cleaning the backside of a wafer, and after executing step S72, the transfer robot and the clamping assembly 3 cooperate to allow the transfer robot to grip the wafer, remove it from the clamping assembly 3, and transfer it to the chamber of the next process flow. Then, after completing the cleaning step S8, the scrubbing arm 11 is again controlled to swing until the scrubbing head 12 is located above the trimming table 61, so that step S1 can be executed again. That is, the transfer robot transfers the next wafer to be processed to the clamping assembly 3, and controls the clamping assembly 3 to grip the wafer.

[0197] The wafer backside scrubbing method of the present invention can efficiently clean the contaminant particles on the backside of the wafer, ensuring that the quality of both the front and back surfaces of the wafer meet the requirements of subsequent processes, and can adapt to the existing wafer processing rhythm without affecting the production efficiency of the wafer.

[0198] The present invention further provides a wafer processing device 1000, comprising a controller 200 and a wafer post-processing apparatus 100, wherein the controller 200 is used to control the wafer post-processing apparatus 100 to execute the wafer backside scrubbing method of the present invention.

[0199] In one embodiment, Figure 8 As shown, the wafer post-processing device 100 is located after the polishing unit and before the scrubbing unit, cleaning unit, and drying unit. After the controller controls the polishing unit to complete the front-side polishing of the wafer, the polished wafer is transferred to the wafer post-processing device 100, and the wafer back-side scrubbing method of the present invention is performed in the wafer post-processing device 100. The wafers that have completed the scrubbing process are then transferred to the scrubbing unit, cleaning unit, and drying unit in sequence for scrubbing, cleaning, drying, and other processing processes. This ensures that the quality of both the front and back surfaces of the wafers processed by the wafer processing equipment 1000 meets the requirements of subsequent processes, thereby improving the yield rate of chip manufacturing.

[0200] Those skilled in the art will understand that the wafer post-processing device 100 of the present invention can also be used as an independent wafer back side cleaning equipment machine to transfer wafers whose back side quality needs to be improved to the wafer back side cleaning equipment, thereby processing the back side of the wafer to a state that meets the requirements of subsequent processes without damaging the front side of the wafer.

[0201] In one embodiment, the wafer back side scrubbing equipment of the present invention includes: a scrubbing assembly, a supporting assembly and a clamping assembly; the scrubbing assembly includes a scrubbing arm, a scrubbing head and a scrubbing pad, the scrubbing head is arranged on the scrubbing arm, the scrubbing pad is arranged on the scrubbing head, and the scrubbing head drives the scrubbing pad to rotate; the supporting assembly includes a supporting arm and a supporting head, the supporting head is arranged on the supporting arm, and a plurality of supporting fluid nozzles are distributed on the surface of the supporting head; when processing the wafer, the clamping assembly clamps and drives the wafer to rotate, the wafer is located between the scrubbing pad and the supporting head, the scrubbing pad adheres to the back side of the wafer with scrubbing pressure, there is a gap between the supporting head and the front side of the wafer, the scrubbing arm and the supporting arm swing, and during the swinging process, the scrubbing head and the supporting head are always opposite, the supporting fluid nozzles continuously spray supporting fluid toward the front side of the wafer, and the scrubbing pressure is not greater than the supporting force of the fluid on the front side of the wafer.

[0202] The above implementation methods are only used to illustrate the embodiments of the present invention, and are not intended to limit the embodiments of the present invention. Ordinary technicians in the relevant technical field may make various changes and modifications without departing from the spirit and scope of the embodiments of the present invention. Therefore, all equivalent technical solutions also fall within the scope of the embodiments of the present invention, and the scope of patent protection of the embodiments of the present invention should be defined by the claims.

Claims

1. A wafer post-processing device, characterized in that: include: scrubbing assembly, supporting assembly and clamping assembly; The scrubbing assembly includes a scrubbing arm, a scrubbing head, a scrubbing pad, a rotating lifting element, and a scrubbing fluid passage, wherein the scrubbing pad is mounted on the scrubbing head; The support assembly includes a support arm and a support head, and the surface of the support head has a plurality of support fluid spray holes; When processing wafers, The clamping assembly clamps and drives the wafer to rotate. The wafer is located between the scrubbing pad and the support head. There is a gap between the surface of the support head and the front of the wafer. The scrubbing pad adheres to the back of the wafer with scrubbing pressure and rotates driven by the scrubbing head. The scrubbing fluid channel supplies scrubbing fluid to the back of the wafer. The scrubbing head and the supporting head swing back and forth between the center and edge of the wafer and always keep aligned during the swinging process. The supporting fluid nozzle continuously sprays supporting fluid to the front of the wafer to support the wafer and prevent the surface of the supporting head from contacting the front of the wafer. The rotary lifting element adjusts the scrubbing pressure by lifting the scrubbing head so that the wafer deforms differently when the scrubbing head is located at the center and edge of the wafer, which is conducive to the discharge of contaminants. This removes deep residual contaminants, chemically bonded residual contaminants or microscopic defects on the back of the wafer without damaging the front of the wafer.

2. The wafer post-processing device according to claim 1, wherein: Also included is a dressing assembly for dressing the scrubbing pad, the dressing assembly being disposed on a dressing oscillation path of the scrubbing head, and the scrubbing head being moved along the dressing oscillation path to the dressing assembly; The trimming swing path does not overlap with the scrubbing swing path of the scrubbing head when processing the wafer, so as to prevent contaminants generated when processing the wafer from sputtering to the trimming assembly.

3. The wafer post-processing device according to claim 1, wherein: The rotary lifting element is connected to one end of the lower surface of the scrubbing arm, and the scrubbing head is arranged at the other end of the lower surface of the scrubbing arm. The rotary lifting element is used to enable the scrubbing arm to drive the scrubbing head to swing and lift.

4. The wafer post-processing device according to claim 1, wherein: The rotating lifting element adjusts the scrubbing pressure by lifting the scrubbing head so that when the scrubbing head is located at the center of the wafer and at the edge of the wafer, the wafer undergoes different deformations, including: When the scrubbing head is located at the center of the wafer, the scrubbing pressure is adjusted so that the center of the wafer has an upward warp of 0° to 2° relative to the edge of the wafer, thereby guiding the contaminants to flow toward the edge of the wafer along the arc surface formed by the upward warp; and / or, When the scrubbing head is located at the edge of the wafer, the scrubbing pressure is adjusted to level the wafer to prevent the clamping assembly from slipping.

5. The wafer post-processing device according to any one of claims 3 or 4, characterized in that: The support assembly further includes a rotating element coaxially arranged with the rotating lifting element, the rotating element being connected to one end of the upper surface of the support arm, and the supporting head being arranged at the other end of the upper surface of the support arm; The rotary lifting element includes a rotary motor and a coupling mechanism. The coupling mechanism drives the rotary lifting element and the rotary element to rotate synchronously when the rotary motor rotates through coupling. The coupling mechanism drives only the rotary lifting element to rotate when the rotary motor rotates through decoupling.

6. The wafer post-processing device according to any one of claims 1 to 4, characterized in that: The clamping assembly includes four clamping elements distributed at equal intervals, wherein: The first clamping element and the second clamping element are respectively installed at two ends of the first connecting mechanism, and the first connecting mechanism and the first clamping element are located between the scrubbing arm and the support arm in the vertical direction to avoid interference with the swinging support arm; The third clamping element and the fourth clamping element are respectively mounted at two ends of the second connecting mechanism; A line connecting the first clamping element and the second clamping element is parallel to a line connecting the third clamping element and the fourth clamping element; The first connecting mechanism and the second connecting mechanism move relative to each other in a horizontal direction, so that the four clamping elements move closer to or farther away from each other, thereby clamping the wafer when they move closer and releasing the wafer when they move farther away.

7. The wafer post-processing device according to claim 6, wherein: The first connecting mechanism is a U-shaped plate with an opening facing the wafer; The first clamping element and the second clamping element are respectively mounted on two ends of the upper surface of the first connecting mechanism, and in a horizontal projection, the first clamping element overlaps with the swing path of the support arm, while the second clamping element does not overlap with the swing path of the support arm; A connecting mechanism supporting member is connected to a lower surface of the first connecting mechanism to support the first connecting mechanism, the connecting mechanism supporting member being opposite to the second clamping member.

8. The wafer post-processing device according to claim 7, wherein: The connecting mechanism support element can drive the first connecting mechanism to move horizontally relative to the second connecting mechanism, and drive the second clamping element to rotate; The scrubbing head reciprocates between the center of the wafer and the second clamping element.

9. The wafer post-processing device according to any one of claims 1 to 4, characterized in that: The scrubbing assembly further comprises a scrubbing head shaft, and the scrubbing fluid channel sequentially passes through the scrubbing arm, the scrubbing head shaft, the scrubbing head and the scrubbing pad to supply polishing liquid or cleaning liquid or pure water to the back side of the wafer.

10. The wafer post-processing device according to any one of claims 1 to 4, characterized in that: The support assembly also includes a support head support shaft and a support fluid channel, wherein the support fluid channel sequentially passes through the support arm, the support head support shaft and the support head, and is connected to the support fluid spray hole to supply protective liquid and / or pure water to the support fluid spray hole.

11. The wafer post-processing device according to claim 10, wherein: The surface of the support head is circular, and the width of the gap between the surface of the support head and the front surface of the wafer is 0.3 to 2 mm.

12. The wafer post-processing device according to claim 11, wherein: An annular guide portion is provided on the edge of the surface of the support head along the circumferential direction, the guide portion is made of a flexible material, and the distance between the upper edge of the guide portion and the front surface of the wafer is 0.1 to 1 mm; The guide portion protrudes upward and outward in an arc shape from the edge of the surface of the support head and is retracted inward at the end, so that the supporting fluid forms a supporting fluid film on the front surface of the wafer.

13. The wafer post-processing device according to claim 10, wherein: It also includes a supporting fluid pressure control component for controlling the flow rate and / or pressure of the supporting fluid so that the supporting force of the supporting fluid on the front side of the wafer is consistent with the scrubbing pressure when the scrubbing head is located at the edge of the wafer.

14. The wafer post-processing device according to any one of claims 1 to 4, characterized in that: It also includes a liquid supply component, which includes a cleaning liquid nozzle and a pure water nozzle, and is used to supply cleaning liquid or pure water to the back side of the wafer.

15. The wafer post-processing device according to claim 2, wherein: The dressing assembly includes a dressing table, a dressing piece, and a dressing piece cleaner; The dressing table is rotatable, and the dressing member is mounted on an upper surface of the dressing table for contacting and dressing the scrubbing pad when the scrubbing head swings from the clamping assembly to above the dressing table; The trimming piece cleaner is used to clean the trimming piece after trimming the scrubbing pad.

16. The wafer post-processing device according to claim 2 or 15, characterized in that: It also includes a cleaning component, which is arranged on the trimming swing path of the scrubbing head between the clamping component and the trimming component. The cleaning component is used to spray cleaning liquid or pure water to clean the trimmed scrubbing pad.

17. A wafer backside scrubbing device, characterized in that: include: scrubbing assembly, supporting assembly and clamping assembly; The scrubbing assembly includes a scrubbing arm, a scrubbing head, and a scrubbing pad, wherein the scrubbing head is arranged on the scrubbing arm, the scrubbing pad is arranged on the scrubbing head, and the scrubbing head drives the scrubbing pad to rotate; The support assembly includes a support arm and a support head, wherein the support head is arranged on the support arm, and a plurality of support fluid spray holes are distributed on the surface of the support head; When processing the wafer, the clamping assembly clamps and drives the wafer to rotate, and the wafer is located between the scrubbing pad and the supporting head. The scrubbing pad adheres to the back of the wafer with scrubbing pressure, and there is a gap between the supporting head and the front of the wafer. The scrubbing arm and the supporting arm swing back and forth synchronously, and the scrubbing head and the supporting head are always opposite to each other during the swinging process. The supporting fluid nozzle continuously sprays supporting fluid toward the front of the wafer, and the scrubbing pressure is not greater than the supporting force of the fluid on the front of the wafer. When the scrubbing head is located at the center of the wafer and the edge of the wafer, the wafer undergoes different deformations to remove deep residual contaminants, chemically bonded residual contaminants or microscopic defects on the back of the wafer.

18. A method for scrubbing the back side of a wafer, characterized in that: Scrubbing the back side of a wafer using the wafer post-processing device according to any one of claims 1 to 16, comprising: Transferring the wafer to the clamping assembly, and controlling the clamping assembly to clamp the wafer; Controlling the scrubbing arm to swing until the scrubbing head is located above the center of the wafer and opposite to the support head located below the center of the wafer; Controlling the scrubbing arm to descend until the scrubbing pad contacts the back of the wafer while controlling the supporting fluid to be ejected from the supporting fluid ejection hole; The scrubbing fluid is supplied to the back side of the wafer, and at the same time, the scrubbing arm and the supporting arm are controlled to swing back and forth synchronously, the scrubbing head is controlled to rotate, and the clamping assembly is controlled to drive the wafer to rotate.

19. The wafer backside scrubbing method according to claim 18, wherein: Also includes: Controlling the scrubbing pressure so that when the scrubbing head is located at the center of the wafer, the center of the wafer has an upward warp of 0° to 2° relative to the edge of the wafer to prevent contaminants generated by scrubbing from accumulating on the back side of the wafer; and / or, When the scrubbing head is located at the edge of the wafer, the wafer is level to prevent the clamping assembly from slipping.

20. The wafer backside scrubbing method according to claim 19, wherein: Also includes: When the scrubbing pressure when the scrubbing head is located at the edge of the wafer changes with the use of the scrubbing pad, the flow rate and / or pressure of the supporting fluid is controlled so that the supporting force of the supporting fluid on the front side of the wafer is consistent with the scrubbing pressure when the scrubbing head is located at the edge of the wafer.

21. The wafer backside scrubbing method according to any one of claims 18 to 20, wherein: The supplying of scrubbing fluid to the back side of the wafer comprises: supplying polishing liquid to the back side of the wafer through the scrubbing fluid channel; Stop supplying the polishing liquid, and supplying the cleaning liquid to the back side of the wafer through the scrubbing fluid channel and the liquid supply component of the wafer post-processing device; Stop supplying the cleaning liquid and supply pure water to the back side of the wafer through the scrubbing fluid channel and the liquid supply assembly; stopping supplying pure water to the back side of the wafer through the scrubbing fluid channel; The supply of pure water to the back side of the wafer through the liquid supply assembly is stopped.

22. The wafer backside scrubbing method according to any one of claims 18 to 20, wherein: The supplying of scrubbing fluid to the back side of the wafer comprises: supplying cleaning liquid to the back side of the wafer through the scrubbing fluid channel and the liquid supply component of the wafer post-processing device; Stop supplying the cleaning liquid and supply pure water to the back side of the wafer through the scrubbing fluid channel and the liquid supply assembly; stopping supplying pure water to the back side of the wafer through the scrubbing fluid channel; The supply of pure water to the back side of the wafer through the liquid supply assembly is stopped.

23. The wafer backside scrubbing method according to claim 21, wherein: Also included is a dressing step for dressing the scrubbing pad and a cleaning step for cleaning the trimmed scrubbing pad; In the trimming step, the scrubbing arm rises and swings until the scrubbing head is located at a trimming assembly of the wafer post-processing device; During the cleaning step, the scrubbing arm rises and swings until the scrubbing head is located in a cleaning assembly of the wafer post-processing device; and After the cleaning step, the scrubbing arm is kept stationary, the next wafer is transferred to the clamping assembly, and the clamping assembly is controlled to clamp the next wafer.

24. The wafer backside scrubbing method according to any one of claims 18 to 20, wherein: Controlling the support fluid to be ejected from the support fluid ejection hole comprises: According to the surface film properties of the front side of the wafer, pure water and / or protective liquid is controlled to be sprayed out from the supporting fluid spray holes.

25. A wafer processing device, characterized in that: It comprises a controller and a wafer post-processing device as described in any one of claims 1 to 16, wherein the controller is used to control the wafer post-processing device to execute the wafer back side scrubbing method as described in any one of claims 18 to 24.

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