A device for preventing fog from overflowing in wafer photoresist and metal stripping process

Abstract

The present invention belongs to the field of wafer manufacturing technology, and particularly relates to a device for preventing fog from overflowing in a wafer photoresist and metal stripping process. The device comprises a fixed splash-proof ring, an inner splash-proof ring, a primary filtering device, a lifting splash-proof ring, a lifting splash-proof ring driving mechanism and an exhaust duct, wherein the fixed splash-proof ring, the inner splash-proof ring and the lifting splash-proof ring are nested from outside to inside in sequence, and an annular gap is left between the inner splash-proof ring and the fixed splash-proof ring, the primary filtering device is arranged at the lower end of the inner splash-proof ring, the lifting splash-proof ring driving mechanism is connected to the lifting splash-proof ring, and is used to drive the lifting splash-proof ring to rise and fall, the exhaust duct is connected to the fixed splash-proof ring, and is communicated with the annular gap between the inner splash-proof ring and the fixed splash-proof ring. The present invention has a three-layer filtering system and a unique exhaust flow field, which prevents metal debris from entering the exhaust duct and fog from condensing and accumulating in the exhaust duct, and solves the problems of fog overflow, air duct blockage and low metal recovery rate that occurred when the stripping cavity was used in the past.

Description

Technical Field

[0001] The invention belongs to the technical field of wafer manufacturing, and in particular relates to a device for preventing fog from overflowing during wafer photoresist and metal stripping processes. Background Art

[0002] In the LED industry, wafer processing is divided into several processes, among which the stripping process is a method of using sacrificial materials (such as photoresists) to produce the structure (patterning) of the target material on the surface of the substrate (such as a wafer). When the sacrificial layer (photoresist in a solvent) is washed away, the material on the top is stripped off and washed together with the sacrificial layer below. This process usually uses high temperature and high pressure solvents to strip the photoresist and the precious metals (generally gold, silver, etc.) covering the upper layer, and these precious metals need to be recycled and reused. Generally, during the wet stripping process, due to the effects of high temperature and high pressure, a large amount of mist will be generated in the cavity and mixed with precious metal fines. The metal shavings can easily enter the exhaust duct, which is not conducive to recovery and causes duct blockage. After the mist condenses, it accumulates in the duct, causing the solution to overflow and corrode components, and even cause harm to operators. Summary of the invention

[0003] In view of the above problems, the purpose of the present invention is to provide a device for preventing mist overflow in the wafer photoresist and metal stripping process, so as to solve the problems of mist overflow, air duct blockage and low metal recovery rate that occur during the existing stripping chamber process.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] A device for preventing mist from overflowing in a wafer photoresist and metal stripping process comprises a fixed splash-proof ring, an inner splash-proof ring, a primary filtering device, a lifting splash-proof ring, a lifting splash-proof ring driving mechanism and an exhaust duct, wherein the fixed splash-proof ring, the inner splash-proof ring and the lifting splash-proof ring are nested in sequence from the outside to the inside, and an annular gap is left between the inner splash-proof ring and the fixed splash-proof ring, the primary filtering device is arranged at the lower end of the inner splash-proof ring, the lifting splash-proof ring driving mechanism is connected to the lifting splash-proof ring for driving the lifting and lowering of the lifting splash-proof ring, and the exhaust duct is connected to the fixed splash-proof ring and communicated with the annular gap between the inner splash-proof ring and the fixed splash-proof ring.

[0006] The fixed splash-proof ring includes a fixed splash-proof ring wall, a fixed splash-proof ring bottom plate and an exhaust box, wherein the fixed splash-proof ring bottom plate is arranged at the lower end of the fixed splash-proof ring wall and is sealed and connected to the unit bottom plate of the process chamber, a plurality of exhaust ports are arranged circumferentially along the fixed splash-proof ring wall, each exhaust port is provided with a secondary filter, the exhaust box is arranged on the outer side of the fixed splash-proof ring wall, the exhaust port is located in the exhaust box, and the exhaust duct is connected to the exhaust box.

[0007] Two exhaust boxes are symmetrically arranged on the outer side of the fixed splash-proof ring wall, and the two exhaust boxes are respectively connected to two exhaust pipelines through exhaust pipes.

[0008] An exhaust filter is provided at the connection between the exhaust duct and the exhaust pipe, and the exhaust duct is led out from the process chamber from bottom to top.

[0009] A motor buckle cover connected to the fixed splash-proof ring bottom plate is arranged inside the fixed splash-proof ring wall.

[0010] The upper end of the inner anti-splash ring is connected to the fixed anti-splash ring through a flange.

[0011] The primary filtering device is a primary filtering screen, and the primary filtering screen is made of a metal filtering screen.

[0012] A cover plate is provided on the top of the lifting splash-proof ring, and a process hole is provided at the center of the cover plate.

[0013] A sealing ring and a pressing sheet arranged above the sealing ring are arranged between the upper end edge of the lifting splash-proof ring and the top of the inner splash-proof ring.

[0014] The lifting splash-proof ring driving mechanism comprises two lifting cylinders, which are respectively arranged on both sides of the lifting splash-proof ring, and the output ends of the two lifting cylinders are connected to the lifting splash-proof ring through connecting pieces.

[0015] The advantages and positive effects of the present invention are:

[0016] 1. The exhaust device of the present invention is provided with a three-layer filtering device, which greatly prevents metal debris from entering the air duct, reduces the risk of air duct blockage, and increases the metal recovery rate.

[0017] 2. The inner splash-proof ring of the present invention blocks the exhaust port of the fixed splash-proof ring and forms a sandwich between the two, so that the mist passes through the filter net at the lower end of the inner splash-proof ring and enters the sandwich to the exhaust port, thereby optimizing the exhaust flow field.

[0018] 3. The lifting splash-proof ring cover of the present invention effectively prevents mist and metal chips from overflowing. The opening size of the cover is 2mm to 7mm larger than the outer diameter of the wafer. If it is too large, mist will overflow, and if it is too small, it will easily scratch the wafer and cause damage to it.

[0019] 4. The lifting splash ring of the present invention is linked to the unit door by two cylinders, which improves the stability of the lifting of the splash ring. Under the premise of ensuring stability, the operation time of the unit components can be reduced by increasing the operating speed of the cylinder, thereby improving the production capacity of the machine.

[0020] 5. In the present invention, after the mist condenses into liquid, it flows back along the exhaust duct to the fixed splash-proof ring for discharge, thus avoiding the harm to the equipment caused by the mist condensing into liquid.

[0021] 6. The present invention seals the gap of the cavity through a sealing ring, and no mist overflows from the gap between the two splash-proof rings during the stripping process.

[0022] 7. The present invention provides a plurality of symmetrical exhaust ports on the fixed splash-proof ring to make the flow field in the cavity more uniform.

[0023] 8. The present invention can achieve compatible processing of wafers of different sizes by replacing the lifting splash-proof ring cover.

[0024] 9. The exhaust duct of the present invention is provided with a filter screen, which is fixed by a clamp. When cleaning and recycling metal regularly, the clamp is removed to clean the filter screen and the duct, which is easy to operate and simple to maintain. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of the present invention;

[0026] Figure 2 for Figure 1 The enlarged image at point I in the middle;

[0027] Figure 3 for Figure 1 A top view of

[0028] Figure 4 It is an exploded view of the fixed splash-proof ring and the inner splash-proof ring in the present invention;

[0029] Figure 5 It is an axonometric view of a fixed splash-proof ring in the present invention;

[0030] Figure 6 It is an axonometric view of the lifting splash-proof ring in the present invention.

[0031] Wherein: 1 is a fixed splash-proof ring, 2 is a primary filter screen, 3 is an inner splash-proof ring, 4 is a sealing ring, 5 is a pressing piece, 6 is a secondary filter screen, 7 is an exhaust pipe, 8 is an exhaust filter screen, 9 is a filter screen liner, 10 is a clamp, 11 is a lifting cylinder, 12 is a unit door, 13 is a splash-proof ring adapter plate, 14 is a cover plate, 15 is a lifting splash-proof ring, 16 is a lifting splash-proof ring cylinder, 17 is a cylinder fixing plate, 18 is a splash-proof ring connecting plate, 19 is a unit bottom plate, 20 is a wafer holding table, 21 is a vacuum shaft motor, 22 is a motor lower fixing plate, 23 is a sealing pad, 24 is a process chamber, 101 is a fixed splash-proof ring wall, 102 is a fixed splash-proof ring bottom plate, 103 is a motor buckle cover, 104 is an exhaust box, 105 is an L-shaped exhaust pipe, and 106 is an exhaust port. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] like Figure 1-4 As shown, the present invention provides a device for preventing mist overflow in wafer photoresist and metal stripping processes, comprising a fixed splash-proof ring 1, an inner splash-proof ring 3, a primary filtering device, a lifting splash-proof ring 15, a lifting splash-proof ring driving mechanism and an exhaust duct 7, wherein the fixed splash-proof ring 1, the inner splash-proof ring 3 and the lifting splash-proof ring 15 are nested in sequence from the outside to the inside, and an annular gap is left between the inner splash-proof ring 3 and the fixed splash-proof ring 1, the primary filtering device is arranged at the lower end of the inner splash-proof ring 3, the lifting splash-proof ring driving mechanism is connected to the lifting splash-proof ring 15, and is used to drive the lifting splash-proof ring 15 to rise and fall, and the exhaust duct 7 is connected to the fixed splash-proof ring 1, and is communicated with the annular gap between the inner splash-proof ring 3 and the fixed splash-proof ring 1.

[0034] like Figure 5 As shown, the fixed splash-proof ring 1 includes a fixed splash-proof ring wall 101, a fixed splash-proof ring bottom plate 102 and an exhaust box 104, wherein the fixed splash-proof ring bottom plate is arranged at the lower end of the fixed splash-proof ring wall 101 and is sealed and connected to the unit bottom plate 19 of the process chamber 24, a plurality of exhaust ports 106 are circumferentially arranged on the fixed splash-proof ring wall 101, each exhaust port 106 is provided with a secondary filter 6, the exhaust box 104 is arranged on the outer side of the fixed splash-proof ring wall 101, the exhaust port 106 is located in the exhaust box 104, and the exhaust duct 7 is connected to the exhaust box 104.

[0035] Two exhaust boxes 104 are symmetrically arranged on the outer side of the fixed splashproof ring wall 101, and the two exhaust boxes 104 are respectively connected to two exhaust pipes 7 through exhaust pipes 105. The exhaust pipe 105 is an L-shaped structure, and the exhaust pipe 7 is a curved pipe. An exhaust filter 8 is arranged at the connection between the exhaust pipe 7 and the exhaust pipe 105, and the exhaust pipe 7 is led out from the process chamber 24 from bottom to top.

[0036] A motor buckle cover 103 connected to the fixed splash-proof ring bottom plate 102 is arranged inside the fixed splash-proof ring wall 101. The upper end of the inner splash-proof ring 3 is connected to the fixed splash-proof ring 1 through a flange.

[0037] The primary filtering device is a primary filtering screen 2, and the primary filtering screen 2 is made of a metal filtering screen.

[0038] like Figure 6 As shown, a cover plate 14 is provided on the top of the lifting splash ring 15, and a process hole is provided in the center of the cover plate 14. A sealing ring 4 and a pressing sheet 5 arranged above the sealing ring 4 are provided between the upper edge of the lifting splash ring 15 and the top of the inner splash ring 3, as shown in FIG. Figure 2 shown.

[0039] The lifting splash-proof ring driving mechanism comprises two lifting cylinders 11 , which are respectively arranged on both sides of the lifting splash-proof ring 15 , and the output ends of the two lifting cylinders 11 are connected to the lifting splash-proof ring 15 through connectors.

[0040] Example

[0041] The anti-fog overflow structure of the present invention includes a three-layer splash-proof ring (rubber cup) structure, the upper part of the fixed splash-proof ring bottom plate 102 is annular, the center position is welded to the motor buckle cover 103, the lower part is connected to the unit bottom plate 19 by threads, and there is an annular groove on the outside, which is sealed by a sealing gasket 23, the fixed splash-proof ring wall 101 is welded to the fixed splash-proof ring bottom plate 102, and a plurality of circumferentially evenly distributed exhaust ports 106 are opened 3 to 10 mm below the flange axis, and two exhaust boxes 104 are used to completely wrap and weld it without gaps, the upper end faces of the two exhaust boxes 104 are horizontal and coplanar, the exhaust box 104 is shell-shaped, and the upper end face is fastened to the long strip of secondary filter 6 by threads, and a circular hole is opened at the center position of the vertical direction of the side, and the L-shaped exhaust pipe 105 is horizontally welded to the exhaust box 104, and the flange of the L-shaped exhaust pipe 105 is ensured to be perpendicular to the horizontal plane. In the inner layer of the fixed splash-proof ring wall 101, a strip-shaped secondary filter screen 6 is placed in the exhaust box 104, so that the surface of the secondary filter screen 6 is coplanar with the inner surface of the fixed splash-proof ring wall 101. One end of the flange of the exhaust duct 7 is clamped with the flange of the L-shaped exhaust duct 105 of the fixed splash-proof ring 1 through a clamp 10, and a filter liner 9 and an exhaust filter screen 8 are built between the two flanges, and the other end is vertically upward and connected to the top of the machine through an exhaust hose.

[0042] The inner splash-proof ring 3 is in the shape of a circular ring, and its axial cross section is nearly "T"-shaped. The upper flange is provided with four tapered holes evenly distributed around the circumference and four threaded holes evenly distributed around the circumference. The eight holes are evenly distributed and connected to the fixed splash-proof ring 1 through the tapered holes. A primary filter screen 2 is inlaid on the lower end face of the inner splash-proof ring 3. The bottom flange of the primary filter screen 2 coincides with the bottom plate 102 of the fixed splash-proof ring. The upper end is an "L"-shaped folded edge, so that the lower end face of the inner splash-proof ring 3 is stuck in the folded edge position of the primary filter screen 2. Four evenly distributed long strips are opened in the center position. A filter screen of 10 to 50 mesh is installed at the opening position and placed in the fixed splash-proof ring 1. A single-sided gap of 6 to 12 mm will be formed between the inner splash-proof ring 3 and the fixed splash-proof ring 1. Figure 2 and Figure 3 As shown, an annular anti-corrosion sealing ring 4 is installed above the flange of the inner splash ring 3, and the sealing ring 4 is pressed tightly by connecting the four conical holes on the annular pressure strip 5 with the threaded holes on the inner splash ring 3, and a circular hole corresponding to the lifting splash ring 15 is opened on the ring.

[0043] like Figure 6As shown, the shape of the lifting splash ring 15 is similar to that of the inner splash ring 3, with a wider flange and a longer lower cylinder. Four evenly distributed threaded holes are opened on the inner side of the flange, and eight symmetrical threaded holes are opened on the outer side. The upper end surface is equipped with a splash ring cover plate 14 through the inner threaded holes. The thickness of the cover plate is generally between 1.5mm and 3mm. A circle suitable for the size of the wafer and an opening suitable for the movement trajectory of the nozzle are opened in the center. The size of the circular opening is 2mm to 7mm larger than the outer diameter of the wafer. If it is too large, the mist will overflow, and if it is too small, it will easily scrape the wafer and cause damage to it. The lifting splash ring 15 is connected to the splash ring adapter plate 13 and the splash ring connecting plate 18 through the threaded holes on the outer side of the flange, the splash ring adapter plate 13 is connected to the unit door 12 through threads, the splash ring adapter plate 13 and the unit door 12 are connected to the lifting cylinder 11, and the splash ring connecting plate 18 is connected to the lifting splash ring cylinder 16 through three threaded holes distributed in a triangle, and there are three threaded holes distributed in an inverted triangle at adjacent positions. The relative position of the lifting splash ring is adjusted by the top screw to avoid gaps and lifting jams between the lifting splash ring 15 and the sealing ring 4 and to achieve the linkage lifting of the lifting splash ring 15 and the unit door 12. The air intake speed of the cylinder can be adjusted during the lifting process to ensure stable lifting of the lifting splash ring 15 and the unit door 12. During the stripping process, the lifting splash ring 15 is lifted to prevent liquid and metal from splashing outside. The lifting splash-proof ring 15 and the sealing ring 4 installed on the flange of the inner splash-proof ring 3 are interference fit or transition fit, which effectively prevents the mist from overflowing from the gap between the lifting splash-proof ring and the inner splash-proof ring.

[0044] The working principle of the present invention is:

[0045] During the wafer stripping process, the equipment is first turned on and initialized, and each unit is in the initial working position. After the wafer is placed in the debonding chamber, the lifting splash ring 15 is lifted, and the wafer is adsorbed by the rotating motor 21 and rotated at high speed. The nozzle swings and scans to spray the liquid under the drive of the swing arm. Under the action of the lifting splash ring cover 14, the mist generated under high temperature and high pressure conditions will be mixed with metal chips and fill the entire cavity. If there is no exhaust, the mist will overflow from the opening of the lifting splash ring cover 14, polluting the entire process unit and making it difficult to collect precious metals. In the present invention, the mist will flow from the lower primary filter screen 2 along the gap between the inner splash ring 3 and the fixed splash ring 1 to the upper secondary filter screen 6 into the exhaust box 104. In this process, it passes through two layers of filtration, so that most of the metal chips remain in the fixed splash ring 1, and then enter the exhaust pipe 105 through the exhaust filter screen 8, enter the exhaust pipe 7 and flow out of the machine upward. The last layer of filter screen has a mesh number of 30 to 100 to filter the remaining metal chips. The entire air duct goes upward and passes through the three-layer filtering device, which can effectively block the metal chips in the splash ring. Even if a large amount of mist in the exhaust air condenses into droplets, it will flow back to the fixed splash ring 1 along the air duct, and there will be no accumulation of liquid in the air duct.

[0046] The anti-fog overflow device, three-layer filtration system and unique exhaust flow field used in the wafer photoresist and metal stripping process provided by the present invention prevent metal debris from entering the exhaust duct and fog from condensing and accumulating in the exhaust duct, thus solving the problems of fog overflow, air duct blockage and low metal recovery rate that occurred in the previous stripping chamber process.

[0047] The above description is only an embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, expansion, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A device for preventing mist from overflowing in wafer photoresist and metal stripping processes, characterized in that: The invention comprises a fixed splash-proof ring (1), an inner splash-proof ring (3), a primary filtering device, a lifting splash-proof ring (15), a lifting splash-proof ring driving mechanism and an exhaust pipe (7), wherein the fixed splash-proof ring (1), the inner splash-proof ring (3) and the lifting splash-proof ring (15) are nested in sequence from the outside to the inside, and an annular gap is left between the inner splash-proof ring (3) and the fixed splash-proof ring (1), the primary filtering device is arranged at the lower end of the inner splash-proof ring (3), the lifting splash-proof ring driving mechanism is connected to the lifting splash-proof ring (15) and is used to drive the lifting splash-proof ring (15) to rise and fall, and the exhaust pipe (7) is connected to the fixed splash-proof ring (1) and is communicated with the annular gap between the inner splash-proof ring (3) and the fixed splash-proof ring (1); The fixed splash-proof ring (1) comprises a fixed splash-proof ring wall (101), a fixed splash-proof ring bottom plate (102) and an exhaust box (104), wherein the fixed splash-proof ring bottom plate is arranged at the lower end of the fixed splash-proof ring wall (101) and is sealedly connected to the unit bottom plate (19) of the process chamber (24); a plurality of exhaust ports (106) are arranged along the circumference of the fixed splash-proof ring wall (101), and each exhaust port (106) is provided with a secondary filter screen (6); the exhaust box (104) is arranged on the outer side of the fixed splash-proof ring wall (101), the exhaust port (106) is located in the exhaust box (104), and the exhaust duct (7) is connected to the exhaust box (104); Two exhaust boxes (104) are symmetrically arranged on the outer side of the fixed splash-proof ring wall (101), and the two exhaust boxes (104) are respectively connected to two exhaust pipelines (7) through exhaust pipes (105); An exhaust filter (8) is provided at the connection between the exhaust pipeline (7) and the exhaust pipe (105), and the exhaust pipeline (7) is led out from the process chamber (24) from bottom to top; A cover plate (14) is provided on the top of the lifting splash-proof ring (15), and a process hole is provided at the center of the cover plate (14).

2. The device for preventing mist from overflowing in wafer photoresist and metal stripping process according to claim 1, characterized in that: A motor buckle cover (103) connected to the fixed splash-proof ring bottom plate (102) is provided in the fixed splash-proof ring wall (101).

3. The device for preventing mist from overflowing in wafer photoresist and metal stripping process according to claim 1, characterized in that: The upper end of the inner anti-splash ring (3) is connected to the fixed anti-splash ring (1) via a flange.

4. The device for preventing mist from overflowing in wafer photoresist and metal stripping process according to claim 1, characterized in that: The primary filtering device is a primary filtering screen (2), and the primary filtering screen (2) is made of a metal filtering screen.

5. The device for preventing mist from overflowing in wafer photoresist and metal stripping process according to claim 1, characterized in that: A sealing ring (4) and a pressing sheet (5) arranged above the sealing ring (4) are provided between the upper end edge of the lifting anti-splash ring (15) and the top of the inner anti-splash ring (3).

6. The device for preventing mist from overflowing in wafer photoresist and metal stripping process according to claim 1, characterized in that: The lifting anti-splash ring driving mechanism comprises two lifting cylinders (11), which are respectively arranged on both sides of the lifting anti-splash ring (15), and the output ends of the two lifting cylinders (11) are connected to the lifting anti-splash ring (15) through connecting pieces.

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