Apparatus for drying wafers and method of drying wafers

Abstract

The application discloses a wafer drying device, which comprises a base and at least two top knives; the top of each top knife is provided with a plurality of top knife grooves for placing wafers; the bottom of each top knife is arranged in parallel on the base, so that the plurality of top knife grooves of adjacent top knives are distributed one by one in alignment; the projections of the grooves of the top knife grooves in alignment of adjacent top knives at least partially coincide in the parallel arrangement direction, and the projections of the groove bottoms of the top knife grooves in the same alignment at least partially stagger with each other in the parallel arrangement direction, so that the wafer placed in the top knife groove and the vertical plane form a certain angle. According to the technical scheme, the grooves and the groove bottoms of adjacent top knife grooves are arranged in a staggered manner, so that the wafer is inclined backward or forward, the wafers are prevented from being adsorbed or shaken due to the surface tension of water, and the watermark problem in the wafer drying process is reduced. The application further discloses a method for drying wafers by using the wafer drying device.

Description

Technical Field

[0001] This invention relates to the field of semiconductor wafer technology, and in particular to an apparatus and method for drying wafers. Background Technology

[0002] The cleaning technology for mass production of semiconductor substrates mainly employs wet cleaning processes—RCA cleaning, which primarily involves chemical bath cleaning and wafer drying. Currently, high-speed centrifugal rotary drying and Marangoni drying are widely used for the drying process. High-speed centrifugal rotary drying offers good drying results but can easily cause mechanical damage to the wafer. In the substrate final cleaning process, most drying methods currently employ the Marangoni drying method, which is a drying technique based on changes in surface tension gradients.

[0003] When using the Marangoni drying method, conventional equipment cannot solve the problem of wafer adsorption due to water surface tension during the wafer drying process. During the drying process, especially after multiple wafers are cleaned, the wafers will adsorb each other due to the influence of water surface tension, resulting in watermark residue. Summary of the Invention

[0004] In view of this, the present invention provides a wafer drying apparatus that tilts the wafer backward or forward to prevent the wafers from adsorbing each other due to the surface tension of water, thereby reducing watermark problems during the wafer drying process.

[0005] The present invention also provides a method for drying a wafer including the above-described wafer drying apparatus.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] An apparatus for drying wafers includes: a base and at least two top blades;

[0008] Each of the top blades has multiple top blade slots for placing wafers on its top; the bottom of each of the top blades is arranged in parallel on the base so that the multiple top blade slots of adjacent top blades are aligned one-to-one.

[0009] The slot openings of adjacent top-cutting slots at least partially overlap in the parallel arrangement direction, and the bottoms of the same top-cutting slots at least partially offset in the parallel arrangement direction, so that the wafer placed in the top-cutting slot and the vertical plane form a certain angle.

[0010] Preferably, the number of top cutters is three, namely a first top cutter, a second top cutter, and a third top cutter arranged in parallel;

[0011] The second top cutter is located between the first top cutter and the third top cutter, and the grooves of the first top cutter and the third top cutter are located on the first horizontal plane, while the groove of the second top cutter is located on the second horizontal plane, and the first horizontal plane is located above the second horizontal plane.

[0012] Preferably, the projections of the first top cutter and the third top cutter in their parallel arrangement direction are such that the groove of the first top cutter and the groove of the corresponding third top cutter completely overlap, and the bottom of the groove of the first top cutter and the bottom of the groove of the corresponding third top cutter completely overlap.

[0013] The projections of the first and second top cutters in their parallel arrangement direction, wherein the groove of the first top cutter and the groove of the corresponding second top cutter at least partially overlap, and the bottom of the groove of the first top cutter and the bottom of the groove of the corresponding second top cutter at least partially offset from each other.

[0014] Preferably, the interval between the first horizontal plane and the second horizontal plane is 6mm-6.5mm.

[0015] Preferably, the top cutter groove is a V-shaped groove.

[0016] Preferably, the projections of the first and second top cutters in their parallel arrangement direction, and the interval between the groove bottom of the first top cutter and the groove bottom of the second top cutter is 0.2mm-1mm.

[0017] Preferably, the multiple top cutter grooves of each top cutter are evenly spaced along the extension direction of the top cutter.

[0018] Preferably, it further includes: a limiting component and a stopper;

[0019] The cassette is provided with a plurality of storage slots along its longitudinal direction for storing the wafers, and the number of the plurality of storage slots and the plurality of top knife slots correspond one-to-one;

[0020] The limiting component is disposed on the base and is used to limit the plug so that the longitudinal direction of the plug and the parallel arrangement direction of the top cutter are set at a certain angle.

[0021] In this configuration, after the cassette is installed on the base via the limiting component, the bottom of each wafer located in the storage slot falls into the aligned top knife slot.

[0022] Preferably, the limiting component includes: a first set of limiting blocks and a second set of limiting blocks arranged along the longitudinal direction of the base;

[0023] The first set of limiting blocks includes: a first limiting block and a second limiting block arranged laterally along the base; the second set of limiting blocks includes: a third limiting block and a fourth limiting block arranged laterally along the base, and the interval between the first limiting block and the second limiting block is equal to the interval between the third limiting block and the fourth limiting block.

[0024] A limiting space is formed between the first limiting block, the second limiting block, the third limiting block and the fourth limiting block to assemble the bottom of the plug;

[0025] The end face of the first limiting block that contacts the bottom of the stopper and the end face of the third limiting block that contacts the bottom of the stopper are projected offset from each other in the longitudinal direction of the base; the end faces of the second limiting block that contact the bottom of the stopper and the end faces of the fourth limiting block that contact the bottom of the stopper are projected offset from each other in the longitudinal direction of the base.

[0026] Preferably, the end face of the first limiting block contacting the bottom of the plug and the end face of the third limiting block contacting the bottom of the plug are projected in a longitudinal direction of the base with a distance between them ranging from 0.5mm to 1.5mm.

[0027] The second limiting block contacts the end face of the bottom of the plug, and the end face of the fourth limiting block contacts the bottom of the plug. The projection interval between them on the longitudinal direction of the base is 0.5mm-1.5mm.

[0028] Preferably, the end faces of the first limiting block, the second limiting block, the third limiting block and / or the fourth limiting block that contact the bottom of the stopper include: an inclined surface and a vertical surface connected to each other, wherein the inclined surface is located on the upper side of the vertical surface.

[0029] A method for drying a wafer, using the wafer drying apparatus described above, includes the following steps:

[0030] Multiple wafers are placed one-to-one in multiple top knife slots;

[0031] The wafer located in the top knife groove is dried according to the Marangoni drying process;

[0032] After the wafer drying process is completed, the dried wafer is removed from multiple top-blade slots.

[0033] Preferably, the wafer drying apparatus further includes: a limiting component and a stopper;

[0034] The cassette is provided with a plurality of storage slots along its longitudinal direction for storing the wafers, and the number of the plurality of storage slots and the plurality of top knife slots correspond one-to-one;

[0035] The limiting component is disposed on the base and is used to limit the plug so that the longitudinal direction of the plug and the parallel arrangement direction of the top cutter are set at a certain angle.

[0036] The step of placing the multiple wafers one-to-one into the multiple top knife slots specifically includes:

[0037] The wafers are placed one-to-one into the multiple storage slots of the cassette;

[0038] The retainer is installed on the base via the limiting component, and the bottom of each wafer located in the storage channel falls into the aligned top knife groove.

[0039] As can be seen from the above technical solution, the wafer drying apparatus provided by the present invention, through the staggered arrangement of the groove openings and bottoms of adjacent top knife grooves, allows the wafer to tilt backward or forward, avoiding the wafer from adsorbing or shaking due to the surface tension of water, and reducing the watermark problem during the wafer drying process.

[0040] The present invention also provides a method for drying wafers. Since the above-mentioned device for drying live wafers is used, it has corresponding beneficial effects, which can be referred to the previous description and will not be repeated here. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 This is a schematic diagram of the overall structure of the wafer drying apparatus;

[0043] Figure 2 for Figure 1 A schematic diagram of the structure behind the hidden wafer;

[0044] Figure 3 for Figure 1 Hidden wafer and structural diagram after jamming (3D);

[0045] Figure 4 for Figure 1 Hidden wafer and schematic diagram of the structure after jamming (planar view);

[0046] Figure 5 A schematic diagram showing the structure of the top cutter in conjunction with other components;

[0047] Figure 6A first-view structural diagram of the top cutter and support frame in operation;

[0048] Figure 7 A second-view structural diagram showing the cooperation between the top cutter and the support frame;

[0049] Figure 8 for Figure 7 A magnified view of a portion of the image;

[0050] Figure 9 A schematic diagram of the side view of the top cutter and support frame in conjunction;

[0051] Figure 10 This is a top view of the top cutter mounted behind the support frame (support frame hidden);

[0052] Figure 11 This is a diagram showing the specific arrangement of the limit blocks;

[0053] Figure 12 This is a schematic diagram of the overall structure of the cassette;

[0054] Figure 13 Image 1 shows the surface of a wafer after drying using an existing wafer drying apparatus;

[0055] Figure 14 Image 2 shows the surface of a wafer after drying using an existing wafer drying apparatus;

[0056] Figure 15 This is an image of the wafer surface after drying using the wafer drying apparatus described herein.

[0057] Wherein, 1 represents the base;

[0058] 2 is the top cutter, 21 is the top cutter groove, 22 is the groove opening, 23 is the groove bottom, 24 is the first top cutter, 25 is the second top cutter, and 26 is the third top cutter;

[0059] 3 represents a wafer;

[0060] 4 is a limiting component, 41 is the first limiting block, 42 ​​is the second limiting block, 43 is the third limiting block, and 44 is the fourth limiting block;

[0061] 5 is the stopper, and 51 is the storage slot;

[0062] 6 represents the support frame. Detailed Implementation

[0063] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0064] The wafer drying apparatus provided in the embodiments of the present invention, such as Figures 1-12 As shown, the base 1 and at least two top blades 2;

[0065] Each top blade 2 has multiple top blade slots 21 for placing wafers 3 on its top; the bottom of each top blade 2 is arranged in parallel on the base 1 so that the multiple top blade slots 21 of adjacent top blades 2 are aligned one-to-one; it should be noted that the top blades 2 arranged in parallel can be on the same horizontal plane or on multiple horizontal planes.

[0066] The slot openings 22 of the adjacent top blades 21 are at least partially overlapped in the parallel arrangement direction, and the bottoms 23 of the top blade slots 21 of the same alignment are at least partially offset in the parallel arrangement direction, so that the wafer 3 placed in the top blade slot 21 forms a certain angle with the vertical plane; it should be noted that the parallel arrangement direction is the spacing direction between adjacent top blades 2.

[0067] In the above technical solutions, such as Figure 5 As shown, wafer 3 is placed in the top knife groove 21. Due to the offset of the groove bottom 23 of adjacent top knives 2 in the parallel arrangement direction, the bottom of wafer 3 is subjected to the force of the groove bottom 23 of the adjacent top knives 2. The force acts on the bottom of wafer 3 (causing the bottom of wafer 3 to tilt forward or backward), resulting in the upper part of wafer 3 tilting backward or forward under the action of gravity (the backward tilt of the wafer corresponds to...). Figure 5 The wafer tilts downwards and to the left, while the wafer tilts forward. Figure 5 (The wafer tilts upwards and to the right), thus changing the entire wafer from a vertical state to a backward tilted state.

[0068] It should be noted that when the bottom of wafer 3 is tilted forward, the upper part of wafer 3 is tilted backward under the influence of gravity; when the bottom of wafer 3 is tilted backward, the upper part of wafer 3 is tilted forward under the influence of gravity.

[0069] Compared with the prior art, this technical solution, through the setting of the slot opening 22 and the slot bottom 23 of the adjacent top knife slot 21, makes the wafer tilt backward or forward, avoiding the wafer 3 from adhering to each other or shaking due to the surface tension of water, and reducing the watermark problem during the wafer drying process.

[0070] Optimize the above technical solutions, such as Figures 5-8As shown, there are three top cutters 2, namely the first top cutter 24, the second top cutter 25, and the third top cutter 26 arranged in parallel.

[0071] The second cutting tool 25 is located between the first cutting tool 24 and the third cutting tool 26, and the slots 22 of the first cutting tool 24 and the third cutting tool 26 are located on the first horizontal plane, while the slot 22 of the second cutting tool 25 is located on the second horizontal plane, and the first horizontal plane is above the second horizontal plane.

[0072] In the above technical solution, the height difference between the first top knife 24 and the second top knife 25, and the height difference between the third top knife 26 and the second top knife 25, are the same, which is beneficial for better fixing of the wafer 3. After the wafer 3 is tilted, it only contacts the first top knife 24, the second top knife 25, and the third top knife 26. The first top knife 24 and the third top knife 26 each have one point of contact with the wafer 3 (i.e., the bottom fixing point of the wafer 3), while the second top knife 25 has two points of contact with the wafer 3 (i.e., the bottom fixing point of the wafer 3 and the contact point of the wafer 3 after tilting). With this setting, the device has fewer contact points with the wafer during drying, avoiding film rupture during the alternation of isopropanol gas film and water film, and further solving the problem of watermark residue.

[0073] Further optimize the above technical solutions, such as Figures 5-8 As shown, the first cutting tool 24 and the third cutting tool 26 are arranged in their parallel direction (the parallel direction here is the direction of the interval between the first cutting tool 24 and the third cutting tool 26, as shown). Figure 9 The projection on the direction indicated by the arrow in segment C shows that the groove 22 of the first top cutter 24 and the groove 22 of the corresponding third top cutter 26 are completely coincident, and the groove bottom 23 of the first top cutter 24 and the groove bottom 23 of the corresponding third top cutter 26 are completely coincident.

[0074] The first cutting tool 24 and the second cutting tool 25 are arranged in a parallel direction (the parallel arrangement direction here is the interval direction between the first cutting tool 24 and the second cutting tool 25, such as...). Figure 9 The projection of the first top cutter 24's slot 22 and the corresponding second top cutter 25's slot 22 onto the direction indicated by the arrow in segment A, at least partially overlaps, and the slot bottom 23 of the first top cutter 24 and the corresponding slot bottom 23 of the second top cutter 25 are at least partially offset from each other; it should be noted that the projection of the second top cutter 25 and the third top cutter 26 onto the parallel arrangement direction (here, the parallel arrangement direction is the interval direction between the second top cutter 25 and the third top cutter 26, such as...) Figure 9 (in the direction indicated by the arrow in section B), the groove 22 of the second top cutter 25 and the groove 22 of the corresponding third top cutter 26 at least partially overlap, and the groove bottom 23 of the second top cutter 25 and the groove bottom 23 of the corresponding third top cutter 26 at least partially offset from each other.

[0075] In the above scheme, the coordinated arrangement of the slot 22 and slot bottom 23 of the first top knife 24, the slot 22 and slot bottom 23 of the second top knife 25, and the slot 22 and slot bottom 23 of the third top knife 26 can further improve the stability of the wafer after tilting backward or forward, and further reduce the watermark problem during the wafer drying process. Preferably, the first top knife 24 and the third top knife 26 are symmetrically arranged about the second top knife 25, and the interval between each pair of top knives 2 is equal, wherein the interval between the top knives 2 is in the range of 2.5mm-3.5mm.

[0076] Further optimize the above technical solutions, such as Figure 9 As shown, the interval between the first horizontal plane and the second horizontal plane is 6mm-6.5mm, which better matches the size and curvature of the wafer 3 surface and is conducive to better fixing the wafer 3. It should be noted that because the interval range is small, it is not shown in the other figures of this specification.

[0077] Further optimize the above technical solutions, such as Figure 8 and Figure 10 As shown, the top cutter groove 21 is a V-shaped groove;

[0078] The projections of the first cutting tool 24 and the second cutting tool 25 in their parallel arrangement direction show that the slot 22 of the first cutting tool 24 and the corresponding slot 22 of the second cutting tool 25 at least partially overlap, and the slot bottom 23 of the first cutting tool 24 and the corresponding slot bottom 23 of the second cutting tool 25 are offset from each other; it should be noted that the projections of the second cutting tool 25 and the third cutting tool 26 in their parallel arrangement direction show that the slot 22 of the second cutting tool 25 and the corresponding slot 22 of the third cutting tool 26 at least partially overlap, and the slot bottom 23 of the second cutting tool 25 and the corresponding slot bottom 23 of the third cutting tool 26 are offset from each other.

[0079] In the above technical solution, the V-groove setting can better fix the wafer 3, further improve the drying effect, and further avoid watermark problems during the wafer drying process.

[0080] Optimize the above technical solutions, Figure 10 As shown, the projections of the first top blade 24 and the second top blade 25 in their parallel arrangement direction are shown. The gap between the bottom 23 of the first top blade 24 and the bottom 23 of the second top blade 25 is 0.2mm-1mm. This setting allows the wafer to be placed behind the top blades and tilted forward or backward. It should also be noted that since the first top blade 24 and the third top blade 26 are aligned, the gap between the bottom 23 of the third top blade 2 and the bottom 23 of the second top blade 25 is also 0.2mm-1mm.

[0081] Figure 7 and Figure 8As shown, the multiple top knife grooves 21 of each top knife 2 are evenly spaced along the extension direction of the top knife 2. The evenly spaced arrangement of the top knife grooves 21 makes it easier to place the wafer and stabilize the structure. At the same time, multiple wafers can be dried.

[0082] In this technical solution, such as Figure 5 , Figure 11 as well as Figure 12 As shown, it also includes: a limiting component 4 and a stopper 5;

[0083] The cassette 5 is provided with multiple storage channels 51 along its longitudinal direction for storing wafers 3, and the number of multiple storage channels 51 and multiple top knife slots 21 correspond one-to-one;

[0084] The limiting component 4 is set on the base 1 to limit the plug 5 so that the longitudinal direction of the plug and the parallel arrangement direction of the ejector tool are set at a certain angle.

[0085] Among them, after the cartridge 5 is installed on the base 1 through the limiting component 4, the bottom of the wafer 3 located in the storage channel 51 falls into the aligned top knife groove 21 one by one.

[0086] In the above technical solution, due to the cooperation between the stopper 5 and the limiting component 4, when the stopper 5 falls into the base 1, the stopper 5 shifts to the upper left and lower right sides of the longitudinal direction of the base 1. Figure 5 On the upper left and lower right sides, the parallel relationship between the wafer 3 and the slot 51 in the cassette 5 is disrupted. After the bottom of the wafer 3 falls into the aligned top knife slot 21, the upper half of the wafer 3 tilts forward or backward under the action of gravity. It should be noted that when the cassette 5 shifts to the lower right side when it falls into the base 1, the upper half of the wafer 3 tilts backward under the action of gravity after the bottom of the wafer 3 falls into the aligned top knife slot 21. The same applies when the cassette 5 shifts to the upper left side when it falls into the base 1. These are not described in detail.

[0087] Optimize the above technical solutions, such as Figure 11 As shown, the limiting component 4 includes: a first set of limiting blocks and a second set of limiting blocks arranged along the longitudinal direction of the base 1;

[0088] The first set of limiting blocks includes: a first limiting block 41 and a second limiting block 42 arranged laterally along the base 1; the second set of limiting blocks includes: a third limiting block 43 and a fourth limiting block 44 arranged laterally along the base 1, wherein the interval between the first limiting block 41 and the second limiting block 42 is equal to the interval between the third limiting block 43 and the fourth limiting block 44; it should be noted that the lateral direction of the base 1 is... Figure 11 The vertical direction of the base 1 is [not specified], and the horizontal direction of the base 1 is [not specified]. Figure 11 The direction indicated by the arrow in the image;

[0089] A limiting space is formed between the first limiting block 41, the second limiting block 42, the third limiting block 43 and the fourth limiting block 44 to assemble the bottom of the stopper 5;

[0090] The first limiting block 41 and the end face of the bottom of the contact plug 5 are projected off from each other in the longitudinal direction of the base 1, as are the end faces of the third limiting block 43 and the bottom of the contact plug 5; the second limiting block 42 and the end face of the bottom of the contact plug 5 are projected off from each other in the longitudinal direction of the base 1, as are the end faces of the fourth limiting block 44 and the bottom of the contact plug 5.

[0091] In the above technical solution, the arrangement of the first limiting block 41, the second limiting block 42, the third limiting block 43, and the fourth limiting block 44 in different directions makes the limiting space a virtual parallelogram (e.g., Figure 11 As shown by the dotted line in the diagram, the center line of the virtual parallelogram forms a certain angle with the longitudinal direction of the base 1. This arrangement causes the clip 5 to shift to the longitudinal sides of the base 1 when it falls into the base 1.

[0092] To optimize the above technical solutions, such as Figure 11 As shown, the projection interval between the end face of the first limiting block 41 contacting the bottom of the plug 5 and the end face of the third limiting block 43 contacting the bottom of the plug 5 in the longitudinal direction of the base 1 is 0.5mm-1.5mm.

[0093] The projection interval between the end face of the second limiting block 42 and the end face of the bottom of the contact plug 5 on the longitudinal direction of the base 1 is 0.5mm-1.5mm.

[0094] In the above technical solution, the projection interval range is 0.5mm-1.5mm, which allows the cartridge 5 to be better offset to the longitudinal sides of the base 1 when it falls into the base 1, thereby improving the drying effect.

[0095] To further optimize the above technical solutions, such as Figure 11 As shown, the end faces of the contact plug 5 at the bottom of the first limiting block 41, the second limiting block 42, the third limiting block 43 and / or the fourth limiting block 44 include: an inclined surface and a vertical surface connected to each other. The inclined surface is located on the upper side of the vertical surface. The inclined surface is a ramp. Guided by the ramp, the plug 5 is offset to both sides of the longitudinal direction of the base 1 when it falls into the base 1, and the parallel relationship between the wafer 3 and the storage slot 51 in the plug 5 is disrupted. It should also be noted that the wafer 3 tilts backward under the action of the second top knife 25 and the weight of the wafer 3 itself. The top position of the slot 51 of the plug 5, which is offset to the right and forward, contacts the lower left side of the wafer 3 (the back side of the wafer 3), which increases the stability of the wafer 3. During the process of the wafer entering the device and during the slow drying process, the wafer 3 is prevented from shaking back and forth due to the surface tension of water, and the generation of watermarks is reduced.

[0096] This technical solution also includes: a support frame 6; the top blade 2 is mounted on the base 1 through the support frame 6. The support frame 6 is used to make the top blade 2 and the base 1 a certain distance apart, which helps to isolate the water vapor at the bottom and improve the drying effect.

[0097] A method for drying a wafer, using the wafer drying apparatus described above, includes the following steps:

[0098] S1. Place multiple wafers 3 one by one into multiple top knife slots 21. After placing the wafers 3 into the top knife slots 21, the wafers 3 are tilted forward or backward.

[0099] S2. Dry the wafer 3 located in the top knife groove 21 according to the Marangoni drying process;

[0100] It should be noted that the Marangoni drying process includes: First, forming a water film – using flowing ultrapure water to form a thin water film on the outer surface of wafer 3; Second, introducing a large amount of nitrogen gas carrying isopropanol gas (IPA); Third, controlling the movement speed of the ultrapure water layer and the isopropanol gas layer on the wafer surface to generate a surface tension gradient, thereby removing moisture.

[0101] S3. After the wafer 3 has finished drying, the dried wafer 3 is taken out from the multiple top knife slots 21.

[0102] To optimize the above technical solution, the wafer drying apparatus also includes: a limiting component 4 and a stopper 5;

[0103] The cassette 5 is provided with multiple storage channels 51 along its longitudinal direction for storing wafers 3, and the number of multiple storage channels 51 and multiple top knife slots 21 correspond one-to-one;

[0104] The limiting component 4 is set on the base 1 to limit the jamb 5 so that the longitudinal direction of the jamb 5 and the parallel arrangement direction of the ejector 2 are set at a certain angle.

[0105] Placing multiple wafers 3 one-to-one within multiple top knife slots 21 specifically includes:

[0106] The cartridge 5 is mounted on the base 1 by the limiting components 4, and the bottom of the wafer 3 located in the storage slot 51 falls into the aligned top knife slot 21 one by one.

[0107] In the above technical solution, the wafer drying apparatus of the present invention (with a 6-inch silicon carbide wafer pre-placed) is placed in a Marangoni drying chamber and inspected on a KLA8520 machine. The wafer surface is observed under the SCN channel, and no watermark residue (such as...) is found. Figure 15 (as shown); Figure 13 and Figure 14 The wafer surface after drying using existing wafer drying equipment.

[0108] The wafer drying apparatus of the present invention can increase the yield of SCN white (watermark) from 43% to 99.8%.

[0109] In some implementations, the robotic arm transfers the cassette 5 containing the wafer 3 to the device and slowly lowers it, gradually separating the wafer 3 from the cassette, and then lifting the wafer 3 upwards.

[0110] The technical features mentioned above, those to be mentioned below, and those shown individually in the accompanying drawings can be combined arbitrarily, provided that the combined technical features are not contradictory. All feasible combinations of features are the technical content explicitly described herein. Any one of the multiple sub-features contained in the same statement can be applied independently, without necessarily being applied together with other sub-features.

[0111] The beneficial effects of this invention are:

[0112] I. This solution designs the structure and relative positions of each component in the device. The entire device has only four contact points with the wafer surface. However, the wafer can remain stable when subjected to the surface tension of water during the drying process. The small contact area between the wafer and the chuck / top knife avoids the formation of watermarks on the wafer surface, thus preventing contamination of the silicon carbide wafer.

[0113] Second, using this drying device, there are no cleaning problems with the wafers after drying, the SCN white yield is increased, there are no water stains, and the particle size is basically not increased, thus improving the application quality of the wafers.

[0114] III. This drying device can be used for drying 6 / 8-inch silicon carbide (silicon) substrate wafers / epitaxial wafers.

[0115] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0116] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An apparatus for drying wafers, characterized in that, include: Base (1), limiting component (4), jammer (5) and at least two top blades (2); Each of the top blades (2) has multiple top blade slots (21) for placing wafers (3) on its top; the bottom of each of the top blades (2) is arranged in parallel on the base (1) so that the multiple top blade slots (21) of adjacent top blades (2) are aligned one-to-one. The slot openings (22) of the adjacent top knife slots (21) are at least partially overlapped in the parallel arrangement direction, and the bottoms (23) of the top knife slots (21) are at least partially offset in the parallel arrangement direction, so that the wafer (3) placed in the top knife slot (21) and the vertical plane form a certain angle. The number of top cutters (2) is three, namely the first top cutter (24), the second top cutter (25) and the third top cutter (26) arranged in parallel. The second top cutter (25) is located between the first top cutter (24) and the third top cutter (26), and the slot (22) of the first top cutter (24) and the slot (22) of the third top cutter (26) are located on the first horizontal plane, and the slot (22) of the second top cutter (25) is located on the second horizontal plane, and the first horizontal plane is located above the second horizontal plane; The projections of the first top cutter (24) and the third top cutter (26) in their parallel arrangement direction are such that the slot (22) of the first top cutter (24) and the slot (22) of the corresponding third top cutter (26) completely overlap, and the bottom (23) of the slot of the first top cutter (24) and the bottom (23) of the corresponding third top cutter (26) completely overlap. The projections of the first top cutter (24) and the second top cutter (25) in their parallel arrangement direction, the slot (22) of the first top cutter (24) and the slot (22) of the corresponding second top cutter (25) at least partially overlap, and the bottom (23) of the slot of the first top cutter (24) and the bottom (23) of the corresponding slot of the second top cutter (25) at least partially offset from each other; The cassette (5) is provided with a plurality of storage channels (51) along its longitudinal direction for storing the wafer (3), and the number of the plurality of storage channels (51) and the plurality of top knife slots (21) correspond one-to-one; The limiting component (4) is disposed on the base (1) to limit the plug (5) so that the longitudinal direction of the plug (5) and the parallel arrangement direction of the top knife (2) are set at a certain angle; In this process, after the cassette (5) is installed on the base (1) by the limiting component (4), the bottom of the wafer (3) located in the storage channel (51) falls into the aligned top knife groove (21).

2. The wafer drying apparatus according to claim 1, characterized in that, The interval between the first horizontal plane and the second horizontal plane is 6mm-6.5mm.

3. The wafer drying apparatus according to claim 1, characterized in that, The top cutter groove (21) is a V-shaped groove.

4. The wafer drying apparatus according to claim 3, characterized in that, The projections of the first top cutter (24) and the second top cutter (25) in their parallel arrangement direction, the interval between the groove bottom (23) of the first top cutter (24) and the groove bottom (23) of the second top cutter (25) is 0.2mm-1mm.

5. The wafer drying apparatus according to claim 1, characterized in that, The multiple top cutter grooves (21) of each top cutter (2) are evenly spaced along the extension direction of the top cutter (2).

6. The wafer drying apparatus according to claim 1, characterized in that, The limiting component (4) includes: a first set of limiting blocks and a second set of limiting blocks arranged along the longitudinal direction of the base (1); The first set of limiting blocks includes: a first limiting block (41) and a second limiting block (42) arranged laterally along the base (1); the second set of limiting blocks includes: a third limiting block (43) and a fourth limiting block (44) arranged laterally along the base (1), and the interval between the first limiting block (41) and the second limiting block (42) is equal to the interval between the third limiting block (43) and the fourth limiting block (44); A limiting space is formed between the first limiting block (41), the second limiting block (42), the third limiting block (43) and the fourth limiting block (44) to assemble the bottom of the plug (5); The first limiting block (41) contacts the end face of the bottom of the plug (5), and the end face of the third limiting block (43) contacts the end face of the bottom of the plug (5) is projected to be offset from each other in the longitudinal direction of the base (1); the second limiting block (42) contacts the end face of the bottom of the plug (5), and the end face of the fourth limiting block (44) contacts the end face of the bottom of the plug (5) is projected to be offset from each other in the longitudinal direction of the base (1).

7. The wafer drying apparatus according to claim 6, characterized in that, The first limiting block (41) contacts the end face of the bottom of the plug (5), and the third limiting block (43) contacts the end face of the bottom of the plug (5) with a projection interval of 0.5mm-1.5mm in the longitudinal direction of the base (1). The second limiting block (42) contacts the end face of the bottom of the plug (5), and the fourth limiting block (44) contacts the end face of the bottom of the plug (5) with a projection interval of 0.5mm-1.5mm in the longitudinal direction of the base (1).

8. The wafer drying apparatus according to claim 7, characterized in that, The end faces of the first limiting block (41), the second limiting block (42), the third limiting block (43) and / or the fourth limiting block (44) that contact the bottom of the stopper (5) include: an inclined surface and a vertical surface connected to each other, wherein the inclined surface is located on the upper side of the vertical surface.

9. A method for drying wafers, characterized in that, The wafer drying apparatus according to any one of claims 1-8 includes the following steps: Multiple wafers (3) are placed one-to-one in multiple top knife slots (21); The wafer (3) located in the top knife groove (21) is dried according to the Marangoni drying process; After the wafer (3) is dried, the dried wafer (3) is taken out from the multiple top knife slots (21).

10. The method for drying wafers according to claim 9, characterized in that, The wafer drying apparatus further includes: a limiting component (4) and a stopper (5); The cassette (5) is provided with a plurality of storage channels (51) along its longitudinal direction for storing the wafer (3), and the number of the plurality of storage channels (51) and the plurality of top knife slots (21) correspond one-to-one; The limiting component (4) is disposed on the base (1) to limit the plug (5) so that the longitudinal direction of the plug (5) and the parallel arrangement direction of the top knife (2) are set at a certain angle; The step of placing multiple wafers (3) one-to-one in multiple top knife slots (21) specifically includes: Multiple wafers (3) are placed one-to-one in multiple storage slots (51) of the cassette (5); The stopper (5) is installed on the base (1) by the limiting component (4), and the bottom of the wafer (3) located in the storage channel (51) falls into the aligned top knife groove (21).

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