Wafer cleaning equipment

Abstract

A wafer cleaning device includes: a housing to be positioned adjacent to a wafer; a hollow area in the housing; a laser module that outputs a laser beam, the distribution of which includes a first area with a first intensity and a second area with a second intensity greater than the first intensity, the laser beam being output into the hollow area; and a transparent window that covers an upper portion of the hollow area and transmits the laser beam so that the laser beam is incident on the entire lower surface of the wafer.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] Korean Patent Application No. 10-2019-0045209, entitled “Wafer Cleaning Equipment”, filed on April 18, 2019 in the Korean Intellectual Property Office, is incorporated herein by reference in its entirety. Technical Field

[0003] Embodiments relate to wafer cleaning equipment. Background Art

[0004] A wet cleaning process widely used in semiconductor manufacturing is a process of etching a hard mask or the like on a wafer using a high-temperature chemical solution. The wet cleaning process has been performed by a batch device that processes a plurality of wafers as a group at the same time in a conventional manner. When a batch device is used, problems such as flow defects, drying defects, and deterioration of dispersion uniformity may occur on the wafer.

[0005] In order to solve these problems, the use of a single wafer processing equipment that processes each wafer one by one has been urged. However, even in a single wafer equipment, the etching rate (E / R) varies from wafer to wafer. Summary of the invention

[0006] According to one aspect, a wafer cleaning device may include: a housing to be positioned adjacent to a wafer; a hollow area in the housing; a laser module that outputs a laser beam having a distribution including a first area having a first intensity and a second area having a second intensity greater than the first intensity, the laser beam being output into the hollow area; and a transparent window that covers an upper portion of the hollow area and transmits the laser beam so that the laser beam is incident on the entire lower surface of the wafer.

[0007] According to one aspect, a wafer cleaning device may include: a housing to be positioned adjacent to a wafer; a hollow area in the housing; a laser module that outputs a laser beam having a distribution including a central area having a first intensity and an edge area having a second intensity different from the first intensity, the laser beam being output into the hollow area; and a transparent window that covers an upper portion of the hollow area and transmits the laser beam so that the laser beam is incident on the entire lower surface of the wafer.

[0008] According to one aspect, a wafer cleaning device may include: a housing to be positioned adjacent to a wafer, the wafer including a first central area and a first edge area surrounding the first central area; a hollow area in the housing; a laser module to irradiate the wafer with a laser beam, the distribution of the laser beam including a second central area having a first intensity and a second edge area having a second intensity greater than the first intensity; and a transparent window covering an upper portion of the hollow area and transmitting the laser beam. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Features will become apparent to those skilled in the art by describing in detail exemplary embodiments with reference to the accompanying drawings, in which:

[0010] Figure 1 shows a cross-sectional view for explaining a wafer cleaning apparatus according to some embodiments;

[0011] Figure 2 Shown for detailed explanation Figure 1 A top view of a wafer rotating in a wafer cleaning apparatus;

[0012] Figure 3 Shown in detail Figure 1 A bottom view of the lower surface of the wafer;

[0013] Figure 4 Shows Figure 1 operation of the first rotor portion and the second rotor portion;

[0014] Figure 5 Shows Figure 1 Wafer cleaning equipment and cooling modules;

[0015] Figure 6 Shows Figure 1 The path of the laser beam in the wafer cleaning equipment;

[0016] Figure 7 Shows Figure 6 The distribution of the laser beam in the area A1;

[0017] Figure 8 Shows Figure 6 The distribution of the laser beam in the area A2;

[0018] Fig. 9 Shows arrival Figure 1 distribution of the laser beam on the wafer;

[0019] Fig.10 An aspheric lens of a wafer cleaning apparatus according to some embodiments is shown in detail;

[0020] Fig.11 shows a cross-sectional view of a wafer cleaning apparatus according to some embodiments;

[0021] Fig.12 Shown for detailed explanation Fig.11 a view of the shape of a second laser;

[0022] Fig.13 shows a cross-sectional view of a wafer cleaning apparatus according to some embodiments;

[0023] Fig.14 shows a cross-sectional view of a wafer cleaning apparatus according to some embodiments;

[0024] Fig.15 Shows Fig.14 Distortion of the optical system;

[0025] Fig.16 shows a cross-sectional view of a wafer cleaning apparatus according to some embodiments;

[0026] Fig.17 shows a cross-sectional view of a wafer cleaning apparatus according to some embodiments;

[0027] Fig.18 A perspective view showing a laser module of a wafer cleaning apparatus according to some embodiments;

[0028] Fig.19 Shows from Fig.18 A top view of the arrangement of lasers emitted by the laser modules;

[0029] Fig. 20 Shown according to Fig.19 a distributed output of the arrangement of lasers; and

[0030] Fig.21 Graphs are shown for explaining various heating profiles of a wafer cleaning apparatus according to some embodiments. DETAILED DESCRIPTION

[0031] In the following, reference will be made to Figures 1 to 9 Wafer cleaning apparatus according to some embodiments is described.

[0032] Figure 1 A cross-sectional view of a wafer cleaning apparatus according to some embodiments is shown. Figure 2 Shown for detailed explanation Figure 1 A top view of a wafer rotating in a wafer cleaning apparatus.

[0033] refer to Figure 1 and Figure 2The first wafer cleaning apparatus 10 according to some embodiments includes a housing 100 , a rotator 160 , a nozzle 170 , a bowl 180 , a laser module 110 , a hollow area 140 , a reflector 130 , a transparent window 150 , and a fixed rotor module 230 .

[0034] The first direction X may be any direction in the horizontal direction. The second direction Y may be any direction different from the first direction X in the horizontal direction. The second direction Y may intersect with the first direction X. For example, the second direction Y may be a direction perpendicular to the first direction X. The third direction Z may be a direction intersecting with the first direction X and the second direction Y. The third direction Z may be, for example, perpendicular to the first direction X and the second direction Y. The third direction Z may be, for example, a vertical direction. Therefore, the first direction X, the second direction Y, and the third direction Z may be directions orthogonal to each other.

[0035] The housing 100 may be located below the wafer W. That is, the housing 100 and the wafer W may be continuously disposed in the third direction Z. The housing 100 may heat the lower surface W1 of the wafer W. The upper surface of the housing 100 may be adjacent to the lower surface W1 of the wafer W. However, the housing 100 and the wafer W may not contact each other.

[0036] The housing 100 may include a laser module 110, a hollow area 140, a reflector 130, and a transparent window 150. The housing 100 may be used to fix and support the positions of the laser module 110, the hollow area 140, the reflector 130, and the transparent window 150.

[0037] The housing 100 may be fixed below the wafer W. Therefore, even if the wafer W rotates in the first rotation direction a1 or the second rotation direction a2, the housing 100 may not rotate. In an embodiment, the housing 100 may also rotate together with the wafer W or may rotate separately.

[0038] The rotator 160 may include a clamping portion 161 , a chemical discharge guide 163 , an insulating block 164 , a first rotor portion 165 , a sidewall portion 168 , a bearing 166 , and a fixing portion 167 .

[0039] The clamping portion 161 may be a portion that contacts the side surface Ws of the wafer W to fix the wafer W. The clamping portion 161 together with the wafer W may rotate in the first rotation direction a1 or the second rotation direction a2.

[0040] The rotator 160 rotates the wafer W in the first rotation direction a1 or the second rotation direction a2 at an appropriate speed. This is because, if the rotation speed of the rotator 160 is too fast, the edge portion of the wafer W is relatively cooled and the temperature distribution is uneven. In this case, the etching rate between the center portion and the edge portion of the wafer W will also be different. For example, the rotation speed of the rotator 160 can be limited to, for example, 100 rpm to 300 rpm.

[0041] The clamping portion 161 may include a heat insulator. When the wafer W is heated by components in the housing 100 , such as the laser module 110 , the clamping portion 161 blocks heat transfer and can prevent thermal damage to other components of the first wafer cleaning apparatus 10 .

[0042] The chemical discharge guide 163 may guide a discharge path of the chemical solution 171. The chemical discharge guide 163 may be connected to the clamping portion 161. The chemical solution 171 may be pushed out to the side surface Ws of the wafer W by the flow F after being used in the etching process on the upper surface Wu of the wafer W.

[0043] Thereafter, the chemical solution 171 reaches the chemical discharge guide 163 via the clamping portion 161 on the side surface of the wafer W to become a discharged chemical solution 171 o. The discharged chemical solution 171 o may be discharged to the outside along the chemical discharge guide 163.

[0044] Since the chemical discharge guide 163 is located at a lower position than the bowl 180, the chemical solution 171 and the discharged chemical solution 171 can be prevented from leaking to the outside. In other words, the bowl 180 can extend farther than the chemical discharge guide 163 in the third direction Z. This enhances the durability of the first wafer cleaning apparatus 10 and prevents damage due to the discharged chemical solution 171o.

[0045] In addition, the chemical discharge guide 163 may be disposed farther from the wafer W than other components of the rotator 160 (i.e., the insulating block 164, the first rotor portion 165, the sidewall portion 168, the bearing 166, and the fixing portion 167). In other words, the chemical discharge guide 163 may extend toward the bowl 180 away from the wafer W in a horizontal direction (i.e., the first direction X and the second direction Y) to overlap with other components of the rotator 160 in the third direction Z and then extend in the third direction Z. This prevents the discharged chemical solution 1710 from damaging the insulating block 164, the first rotor portion 165, the sidewall portion 168, the bearing 166, and the fixing portion 167.

[0046] The insulating block 164 may constitute a side wall of the rotator 160 between the clamping portion 161 and the chemical discharge guide 163. The insulating block 164 is made of a heat insulator and may serve to block heat received by the clamping portion 161 and the chemical discharge guide 163 without transferring the heat to other components of the rotator 160.

[0047] Insulation block 164 Figure 1 160 is shown as being in contact with the clamping portion 161 and the chemical discharge guide 163. In an embodiment, the position of the insulating block 164 can be anywhere in the rotator 160. In addition, although the insulating block 164 is Figure 1 Although shown as a single component in FIG. 1 , in an embodiment, the insulating block 164 may be disposed at multiple locations.

[0048] The first rotor part 165 can rotate the rotator 160 in a magnetic suspension manner together with the second rotor part 210 to be described later. Since the first rotor part 165 is fixed to the insulating block 164, the side wall part 168, and the clamping part 161 of the rotator 160, the rotator 160 can be rotated as a whole by the rotation of the first rotor part 165. Therefore, the wafer W can also be rotated together with the rotator 160.

[0049] The first rotor portion 165 may include a magnetic material. The first rotor portion 165 and the second rotor portion 210 also including a magnetic material may also generate a rotational force through magnetic force. This will be explained in more detail below.

[0050] The side wall portion 168 may be in contact with the first rotor portion 165 to form a side wall of the rotator 160. Figure 1 160 as being located between the first rotor portion 165 and the bearing 166. In an embodiment, the sidewall portion 168 may include all of the portions that constitute the sidewall of the rotator 160. Thus, the sidewall portion 168 may be a single component or may include multiple components.

[0051] The bearing 166 may be located between the sidewall portion 168 and the fixed portion 167. In an embodiment, the bearing 166 may be provided at any position between the fixed portion 167 and the first rotor portion 165 to be rotated.

[0052] The bearing 166 allows the rotator 160 to rotate. That is, the bearing 166 may be a minimum configuration that allows the rotator 160 to rotate, even if the rotator 160 includes a fixed fixing portion 167. The bearing 166 may rotate along with the rotation of the first rotor portion 165. The bearing 166 may simultaneously connect the fixing portion 167, the side wall portion 168, the first rotor portion 165, the insulating block 164, the clamping portion 161, and the chemical discharge guide 163. This enables the rotator 160 to be fixed and rotated at the same time.

[0053] The fixing portion 167 may fix and support the rotator 160 at the lower portion of the rotator 160. The fixing portion 167 may not rotate. Alternatively, the fixing portion 167 may be connected to the bearing 166 so that a portion of the rotator 160 rotates. Therefore, some portions of the rotator 160 other than the fixing portion 167 may rotate to rotate the wafer W.

[0054] The nozzle 170 may be located above the wafer W and the rotator 160 along the third direction Z. The nozzle 170 may supply the chemical solution 171 to the upper surface Wu of the wafer W, for example, on the central portion of the upper surface Wu of the wafer W. The rotation of the wafer W may cause the chemical solution 171 to spread over the entire upper surface Wu of the wafer W. The first wafer cleaning apparatus 10 may apply a flow F in a downward direction to fix the wafer W and uniformly supply the chemical solution 171. This enables the chemical solution 171 to move from the central portion of the upper surface of the wafer W to the periphery.

[0055] Nozzle 170 Figure 1 1 and 2 , the chemical solution 171 is shown as being sprayed in a downward direction to the upper surface of the wafer W. In an embodiment, the nozzle 170 may be disposed adjacent to the side surface Ws of the wafer W at a point higher than the upper surface Wu of the wafer W along the third direction Z. The nozzle 170 may discharge the chemical solution 171 in the direction of the side surface Ws to supply the chemical solution 171 to the upper surface Wu of the wafer W.

[0056] The chemical solution 171 may be a solution for etching the upper surface of the wafer W. The chemical solution 171 may vary according to the target material to be etched. For example, if the wafer to be etched is SiN or polysilicon, the chemical solution 171 may include, for example, at least one of phosphoric acid, an ammonia solution, and tetramethylammonium hydroxide (TMAH).

[0057] The chemical solution 171 is supplied by the nozzle 170. The nozzle 170 supplies the chemical solution 171 onto the upper surface Wu of the wafer W at an appropriate amount and speed. If the chemical solution 171 is supplied too much or too fast, the temperature rise of the wafer W may be delayed accordingly. Therefore, for example, the nozzle 170 may supply the chemical solution 171 onto the wafer W at a speed of 0.1 L / min to 1 L / min.

[0058] The bowl 180 may be located outside the wafer W, the rotator 160, and the housing 100, for example, spaced apart from these components in the first direction X and the second direction Y. The bowl 180 may extend in the third direction Z to be higher than the upper surface of the wafer W. The bowl 180 may block the outflow of the chemical solution 171 and the smoke from which the chemical solution 171 evaporates. The bowl 180 may prevent other parts of the first wafer cleaning apparatus 10 from being damaged by the chemical solution 171 and the smoke.

[0059] The laser module 110 may be inside the housing 100. The laser module 110 may irradiate the lower surface W1 of the wafer W with the laser beam L. The laser module 110 may be located below the hollow area 140. The laser beam L output by the laser module 110 may pass through the hollow area 140 and the transparent window 150 to reach the lower surface W1 of the wafer W.

[0060] The laser module 110 may include a laser supply portion 111 and an aspherical lens 120. The laser beam of the laser module 110 may be supplied through the laser supply portion 111. The laser supply portion 111 may be connected to the outside to form a path through which the laser beam is provided. The laser supply portion 111 may include, for example, an optical fiber or a waveguide. By supplying the laser beam from a laser outside the first wafer cleaning apparatus 10 via the laser supply portion 111, instead of using a module that uses a reflective mirror that requires a relatively long reflection distance, the size of the first wafer cleaning apparatus 10 may be reduced.

[0061] The aspherical lens 120 may include a plurality of lenses. The aspherical lens 120 may transform a profile of a laser beam supplied by the laser supplying part 111, as explained in more detail below.

[0062] The hollow area 140 may be an empty space in the housing 100. The hollow area 140 may be an area where the laser beam L emitted by the laser module 110 advances to the lower surface of the wafer W.

[0063] The upper surface of the hollow area 140 may be covered by the transparent window 150. This allows the hollow area 140 to be completely isolated from the outside by the housing 100 and the transparent window 150 to prevent the laser module 110 from being contaminated by the chemical solution 171 and the smoke generated by the chemical solution 171.

[0064] The interior of the hollow area 140 may be a vacuum. This can facilitate the advancement of the laser beam L. In an embodiment, the interior of the hollow area 140 may be filled with a gas medium that does not hinder the advancement of the laser beam L.

[0065] The hollow area 140 may have a hemispherical shape, and the reflector 130 may be lined on the surface of the housing 100 defining the hollow area 140. Therefore, the laser beam L reflected by the lower surface W1 of the wafer W is reflected by the reflector 130 to be incident on the lower surface W1 of the wafer W again.

[0066] When the light generated by the laser beam L reflected by the wafer W reaches other parts of the first wafer cleaning apparatus 10, damage to the apparatus may occur. Therefore, the reflector 130 may be used to block the reflected laser from reaching other parts of the first wafer cleaning apparatus 10. At the same time, the reflector 130 may improve the heating efficiency of the wafer W by reflecting the reflected laser again to reach the lower surface W1 of the wafer W.

[0067] The transparent window 150 may be a transparent material through which the laser beam L may pass. For example, the transparent window 150 may be made of quartz. However, the present embodiment is not limited thereto.

[0068] The transparent window 150 and the wafer W may be very close. The interval between the transparent window 150 and the wafer W may be a width d. The width d may be small enough to prevent the laser beam L from being incident on a surface other than the lower surface W1 of the wafer W. If the housing 100 does not rotate with the wafer W, the transparent window 150 and the wafer W may not contact each other.

[0069] Because the entire lower surface W1 of the wafer W needs to be heated, the interface between the lower surface W1 of the wafer W and the transparent window 150 may correspond to each other, for example, may completely overlap along the third direction Z. The side surface Ws of the wafer W may also be exposed to the laser beam L through the transparent window 150 .

[0070] The aspherical lens 120 can transform the laser beam. Specifically, the laser beam L supplied by the laser supply portion 111 can have a Gaussian distribution, and the aspherical lens 120 can transform it into a desired distribution, such as a more uniform intensity distribution, which will be discussed in detail below.

[0071] The fixed rotor module 230 may be spaced apart from the rotator 160. The fixed rotor module 230 may surround the rotator 160. Specifically, the fixed rotor module 230 may be located between the chemical discharge guide 163 and the first rotor portion 165.

[0072] The fixed rotor module 230 may include a second rotor part 210 connected to the rotor support part 220. The second rotor part 210 may include a magnetic material. The second rotor part 210 may generate a rotating force through magnetic force together with the first rotor part 165 described above. The second rotor part 210 is spaced apart from the insulating block 164, the side wall part 168, and the clamping part 161 of the rotator 160, and may be protected by the chemical discharge guide 163.

[0073] Figure 3 Shown in detail Figure 1 A bottom view of the lower surface W1 of the wafer W. Figure 3 , the lower surface W1 of the wafer W may include a central region Rc and an edge region Re. The central region Rc of the wafer W may refer to a central portion of the wafer W, and the edge region Re may refer to an edge region surrounding the central region Rc.

[0074] Reference Figures 1 to 3 , the first wafer cleaning apparatus 10 according to some embodiments may uniformly heat the central region Rc. In addition, the first wafer cleaning apparatus 10 may heat the edge region Re to a different degree than the central region Rc. That is, the first wafer cleaning apparatus 10 may heat the edge region Re more strongly than the central region Rc.

[0075] The first wafer cleaning apparatus 10 may have a flow F in a downward direction on the upper surface Wu of the wafer W. Since the flow F passes the edge or side surface Ws of the wafer W to be discarded from the wafer W, unintended cooling of the edge portion of the wafer W may occur.

[0076] To compensate for the unexpected cooling, the first wafer cleaning apparatus 10 may adjust the properties of the aspheric lens 120 and / or the reflector 130 to adjust the distribution of the laser beam L. Therefore, the central region Rc of the lower surface W1 of the wafer W may be uniformly heated, and the edge region Re thereof may be relatively strongly heated compared to the central region Rc.

[0077] The laser beam L of the laser module 110 may be a continuous wave laser beam that is continuously irradiated without turning the laser on / off. Of course, the frequency and wavelength components of the laser beam itself also exist in the continuous wave laser beam. The laser beam L of the laser module 110 may be continuously irradiated with a constant intensity and wavelength region. Using a continuous wave laser beam may significantly improve the temperature rise efficiency and etching rate of the first wafer cleaning device 10.

[0078] In an embodiment, the laser beam L of the laser module 110 of the first wafer cleaning device 10 may be a pulsed laser beam generated when the laser is periodically turned on / off and the laser is irradiated discontinuously. Of course, in addition to the above-mentioned on / off frequency, when the laser is turned on, the frequency and wavelength components of the laser itself also exist in the pulsed laser beam.

[0079] The period of the pulsed laser beam L may be in units of several nanoseconds (nsec) or several picoseconds (psec). Specifically, the frequency of the pulsed laser beam L may be 10 MHz to 1000 MHz. If the frequency is too low, it is not suitable because physical punching rather than heating may be performed on the wafer. Even without adjusting the thermal energy, the pulse frequency of the pulsed laser beam L may be changed to adjust the heating intensity.

[0080] Figure 4 Shows Figure 1 The operation of the first rotor part and the second rotor part. Figures 1 to 4 , the first rotor portion 165 may include a first magnetic pole region 165a and a second magnetic pole region 165b having different magnetic poles from each other. For example, the first magnetic pole region 165a may be an N pole, and the second magnetic pole region 165b may be an S pole, or vice versa. The first magnetic pole region 165a and the second magnetic pole region 165b may be arranged alternately with each other.

[0081] Similarly, the second rotor portion 210 may include a first magnetic pole region 210a and a second magnetic pole region 210b having different magnetic poles from each other. For example, the first magnetic pole region 210a may be an N pole, and the second magnetic pole region 210b may be an S pole, or vice versa. Alternatively, the first magnetic pole region 210a of the second rotor portion may be an S pole, and the second magnetic pole region 210b of the second rotor portion may be an N pole.

[0082] The magnetic poles of the first magnetic pole region 165a of the first rotor portion may be the same as the magnetic poles of the first magnetic pole region 210a of the second rotor portion. The magnetic poles of the second magnetic pole region 165b of the first rotor portion may be the same as the magnetic poles of the second magnetic pole region 210b of the second rotor portion.

[0083] The first magnetic pole region 165a of the first rotor part, the second magnetic pole region 165b of the first rotor part, the first magnetic pole region 210a of the second rotor part, and the second magnetic pole region 210b of the second rotor part may be arranged alternately with each other. The first magnetic pole region 165a of the first rotor part, the second magnetic pole region 165b of the first rotor part, the first magnetic pole region 210a of the second rotor part, and the second magnetic pole region 210b of the second rotor part may be implemented by an electromagnet.

[0084] Since the first magnetic pole region 165a of the first rotor part, the second magnetic pole region 165b of the first rotor part, the first magnetic pole region 210a of the second rotor part and the second magnetic pole region 210b of the second rotor part are arranged alternately with each other, the first rotor part 165 can rotate in the first rotation direction a1 and the second rotation direction a2.

[0085] Specifically, the first magnetic pole region 165a of the first rotor portion and the first magnetic pole region 210a of the second rotor portion have a force that pushes each other, and the first magnetic pole region 165a of the first rotor portion and the second magnetic pole region 210b of the second rotor portion have a force that attracts each other. Similarly, the second magnetic pole region 165b of the first rotor portion and the second magnetic pole region 210b of the second rotor portion have a force that pushes each other, and the second magnetic pole region 165b of the first rotor portion and the first magnetic pole region 210a of the second rotor portion have a force that attracts each other.

[0086] As a result, the first rotor part 165 and the second rotor part 210, which are alternately arranged, have a rotational force so that different regions face each other. That is, the first rotor part 165 and the second rotor part 210 rotate toward the side where the first magnetic pole region 165a of the first rotor part and the second magnetic pole region 210b of the second rotor part face each other, and the second magnetic pole region 165b of the first rotor part and the first magnetic pole region 210a of the second rotor part face each other. Thereafter, if the magnetic pole region in which the first rotor part 165 or the second rotor part 210 is alternately arranged is reversed, the rotation can be further accelerated again.

[0087] In this way, the rotator 160 can rotate according to the magnetic suspension method. In this manner of the first wafer cleaning device 10 according to some embodiments, since the rotational force is generated without contact, mechanical wear is limited and durability can be maintained. In addition, since heat conduction does not occur, the expected life of the device can also be extended. Finally, since there is no friction, the rotation of the wafer W can be performed uniformly and stably.

[0088] The rotor support part 220 may support the second rotor part 210 below the second rotor part 210. The rotor support part 220 may be fixed to the second rotor part 210. The rotor support part 220 may have a fixed position. Therefore, the second rotor part 210 is also fixed, and the first rotor part 165, which is relatively rotatable through the bearing 166, may rotate in the first rotation direction a1 or the second rotation direction a2.

[0089] Since the first rotor portion 165 and the second rotor portion 210 are magnetic materials, they may be sensitive to heat. Therefore, the refrigerant C may be provided between the first rotor portion 165 and the second rotor portion 210 to cool the first rotor portion 165 and the second rotor portion 210. The refrigerant C may be, for example, N 2 gas.

[0090] Figure 5 Shows Figure 1 Wafer cleaning equipment and cooling modules. Figure 5 , the cooling module 240 may provide the refrigerant C to the first wafer cleaning apparatus 10. Therefore, the first wafer cleaning apparatus 10 may cool the first rotor part 165 and the second rotor part 210. In an embodiment, the cooling module 240 may be located inside the first wafer cleaning apparatus 10.

[0091] Figure 6 Shows Figure 1 The path of the laser beam outside the wafer cleaning equipment. Figure 7 Shows Figure 6 Distribution of the laser beam in area A1. Figure 8 Shown in Figure 6 Distribution of the laser beam in area A2. Fig. 9 Shows the incident Figure 1 Distribution of the laser beam on the wafer.

[0092] Reference Figures 6 to 9 In the first wafer cleaning apparatus 10 according to some embodiments, the aspherical lens 120 may expand the laser beam L to be wider than the transparent window 150 and the wafer W. Therefore, the outermost portion of the laser beam L is incident on the reflector 130, instead of the lower surface Wl of the wafer W, and then is reflected to be incident on the lower surface Wl of the wafer W. Light having the lowest energy (e.g., red light Lr) may be located at the outermost portion of the laser beam L. Light having higher energy (e.g., yellow light Ly and green light Lg) may be located inside the red light Lr. Figure 6 , for convenience, the red light Lr, the yellow light Ly, and the green light Lg are shown as being separated from each other, but the red light Lr, the yellow light Ly, and the green light Lg are continuous in the laser beam L, and lights of other colors in between are omitted.

[0093] exist Figure 7 , the energies of red light Lr, yellow light Ly, and green light Lg in region A1 are shown. The energy of red light Lr is the lowest, and the energy of green light Lg is the highest. Yellow light Ly has an energy between red light Lr and green light Lg. Figure 8, in area A2, after having been reflected by the reflector 130, the positions of the red light Lr, the yellow light Ly, and the green light Lg are reversed, the green light Lg is irradiated to the outermost side, and the yellow light Ly and the red light Lr may be irradiated to the inside in sequence.

[0094] Because the laser beam L is directly incident on and reflected on the edge region Re, but is only directly incident on the center region Rc, light having a higher intensity than the light incident on the center region Rc may be incident on the edge region Re, as shown in FIG. Fig. 9 In other words, the distribution of the laser beam incident on the wafer may have a first region with a first intensity, such as incident on the central region Rc, and a second region with a second intensity, such as incident on the edge region Re. Fig. 9 As shown, the second intensity may be greater than the first intensity. Thus, additional heating of the edge region Re may increase the etching rate of the edge region Re to provide a consistent etching rate across the wafer W, or may be used to intentionally etch the edge region Re further than the center region Rc. In an embodiment, different laser beam profiles with different intensity regions may be incident on the wafer to control the heating profile of the wafer, and thus the etching rate across the wafer.

[0095] In the following, reference will be made to Figure 1 , Figure 3 and Fig.10 A first wafer cleaning apparatus 10 according to some embodiments is described. Repeated parts of the above embodiments will be simplified or omitted. Fig.10 is a view for explaining in detail an aspherical lens of a wafer cleaning apparatus according to some embodiments.

[0096] Reference Figure 1 , Figure 3 and Fig.10 The aspherical lens 120 of the first wafer cleaning apparatus 10 according to some embodiments may include a first lens 121, a second lens 122, and a third lens 123. Although three lenses are shown, the number of lenses may be variously changed as needed.

[0097] The first lens 121, the second lens 122, and the third lens 123 provide the laser beam L to the lower surface W1 of the wafer W in an appropriate distribution by refraction. Because the first gap g1 between the second lens 122 and the third lens 123 is adjusted, the distribution of the laser beam L also changes. Therefore, by adjusting the first gap g1, the aspheric lens 120 can further heat the edge area Re of the wafer W instead of the central area Rc. For example, the size of the edge area Re can be changed according to the size of the first gap g1. By adjusting the first gap g1, the second gap g2 can be changed. Therefore, the aspheric lens 120 can adjust the distribution of the laser beam L through the first gap g1 and the second gap g2.

[0098] The first gap g1 and the second gap g2 may be selected and fixed when manufacturing the first wafer cleaning apparatus 10, and may be adjustable in real time according to the size and type of the wafer W. If the first gap g1 and the second gap g2 are adjustable, an optimized cleaning process may be performed on several types of wafers W.

[0099] Fig.10 The change of the first gap g1 between the second lens 122 and the third lens 123 is exemplarily shown, but the gap between the first lens 121 and the second lens 122 may also be adjusted. In addition, if more lenses are included, the gaps between the respective lenses may be precisely adjusted to adjust the distribution of the laser beam L. In addition, the beam diameter or area of ​​the laser beam incident on the first lens 121 may be adjusted to adjust the final distribution of the laser beam L.

[0100] In the following, reference will be made to Figure 3 , Fig.11 and Fig.12 The second wafer cleaning apparatus 11 according to some embodiments is described. The repeated parts of the above-mentioned embodiments will be simplified or omitted. Fig.11 is a cross-sectional view for explaining a wafer cleaning apparatus according to some embodiments, Fig.12 is used to explain in detail Fig.11 A view of the shape of the second laser.

[0101] refer to Figure 3 , Fig.11 and Fig.12 According to some embodiments, the second wafer cleaning apparatus 11 includes a first laser module 110a and a second laser module 110b. Fig.11 Two laser modules are shown, but some embodiments may include three or more laser modules.

[0102] The first laser module 110a, the first laser supply part 111a, and the first aspherical lens 120a may be respectively Figure 1 The laser module 110, the laser supply part 111 and the aspherical lens 120 are the same. Fig.11 In, different from Figure 1 , the first laser module 110 a is disposed to be inclined with respect to the side of the hollow area 140 rather than being disposed at the center of the hollow area 140 .

[0103] The first laser beam La emitted by the first laser module 110a may uniformly heat the lower surface of the wafer W. For example, the first laser beam La may not be wider than the transparent window 150 so that the first laser beam La is not incident on and reflected by the reflector 130. Therefore, the first laser beam La may have a uniform distribution over the entire lower surface W1 of the wafer W (i.e., both the edge region Re and the center region Rc).

[0104] The second laser module 110b may be inside the housing 100. The laser module 110b may irradiate the lower surface W1 of the wafer W with the annular second laser beam Lb. The second laser module 110b may be located below the hollow area 140. The second laser beam Lb output by the second laser module 110b may pass through the hollow area 140 and the transparent window 150 to reach the edge area Re of the lower surface of the wafer W.

[0105] The second laser module 110b may include a second laser supplying part 111b, a refractive lens 120b1, and an axicon lens 120b2. The second laser beam Lb of the second laser module 110b may be supplied by the second laser supplying part 111b. The second laser supplying part 111b may be connected to the outside to form a path for supplying the second laser beam Lb.

[0106] The refractive lens 120b1 may guide the second laser beam Lb of the second laser module 110b to the axicon lens 120b2. That is, the refractive lens 120b1 may refract the second laser beam Lb to reach the axicon lens 120b2. The axicon lens 120b2 may process the second laser beam Lb into a ring shape, such as Fig.12 The axicon lens 120b2 can transform the second laser beam Lb into a symmetrical ring shape to reach the edge region Re of the wafer W.

[0107] Therefore, the second wafer cleaning apparatus 11 according to some embodiments can increase the heating of the edge region Re to increase the etching rate of the edge region Re. Since the ring shape of the second laser beam Lb heats all parts of the edge region Re at the same time, the temperature of the edge region Re can be uniformly increased regardless of the rotation of the edge region Re of the wafer W.

[0108] Now refer to Fig.13 A third wafer cleaning apparatus 12 according to some embodiments is described. Repeated parts of the above-mentioned embodiments will be simplified or omitted. Fig.13 is a cross-sectional view of a wafer cleaning apparatus according to some embodiments. Fig.13 The third wafer cleaning apparatus 12 according to some embodiments may include a beam splitter 115 and a source laser supplying part 116 .

[0109] The beam splitter 115 may receive a supply of a laser beam from the source laser supplying portion 116. The beam splitter 115 may be connected to the first laser supplying portion 111a and the second laser supplying portion 111b. The beam splitter 115 splits the laser supplied from the source laser supplying portion 116 into a first laser beam La and a second laser beam Lb, which are then supplied to the first laser supplying portion 111a and the second laser supplying portion 111b, respectively.

[0110] The first laser beam La output by the first laser module 110a may, for example, uniformly heat the center region Rc and the edge region Re of the wafer W. The second laser beam Lb output by the second laser module 110b may heat only the edge region Re of the wafer W. Therefore, the heating of the edge region Re may be relatively enhanced compared to the heating of the center region Rc.

[0111] In the following, reference will be made to Figure 3 and Fig.14 A fourth wafer cleaning apparatus 13 according to some embodiments is described. Repeated parts of the above-mentioned embodiments will be simplified or omitted. Fig.14 is a cross-sectional view for explaining a wafer cleaning apparatus according to some embodiments. Figure 3 and Fig.14 , the fourth wafer cleaning equipment 13 according to some embodiments may include a third laser module 110 c .

[0112] The third laser module 110c may include a third laser supplying part 111c and a first lens array 120c. The third laser beam Lc of the third laser module 110c may be supplied through the third laser supplying part 111c. The third laser supplying part 111c may be connected to the outside to form a path for supplying the third laser beam Lc.

[0113] The first lens array 120c may guide the third laser beam Lc to be incident on a portion of the edge region Re of the wafer W. Since the wafer W is rotated by the rotator 160, even if the third laser beam Lc is irradiated to a portion of the edge region Re, the entire edge region Re may be heated by the third laser beam Lc during the rotation of the wafer W. Therefore, the fourth wafer cleaning apparatus 13 according to some embodiments may efficiently enhance the heating of the edge region Re at a relatively low cost.

[0114] In the following, reference will be made to Figure 3 , Fig.14 and Fig.15 A fourth wafer cleaning apparatus 13 according to some embodiments is described. Repeated parts of the above-mentioned embodiments will be simplified or omitted. Fig.15 yes Fig.14 The distortion curve of the optical system. Figure 3 , Fig.14 and Fig.15 According to some embodiments, the first lens array 120c of the fourth wafer cleaning apparatus 13 may be a distortion optical system.

[0115] refer to Fig.15 , the distribution of the source laser beam L0 before passing through the first lens array 120c can be converted into a tilted third laser beam Lc. Here, the first lens array 120c is a distortion optical system that distorts the distribution of the source laser beam in one direction, such as a tilted plate. Therefore, the third laser beam Lc can further enhance the heating of the edge region Re.

[0116] In the following, reference will be made to Figure 3 and Fig.16 A fifth wafer cleaning apparatus 14 according to some embodiments is described. Repeated parts of the above-mentioned embodiments will be simplified or omitted. Fig.16 is a cross-sectional view of a wafer cleaning apparatus according to some embodiments. Figure 3 and Fig.16 , the fifth wafer cleaning equipment 14 according to some embodiments may include a fourth laser module 110 d .

[0117] The fourth laser module 110d may be disposed adjacent to the upper surface Wu of the wafer W. The fourth laser module 110d may heat the edge region Re of the wafer W independently of the first laser module 110a heating the lower surface W1 of the wafer W. This enables more efficient heating of the edge region Re.

[0118] The fourth laser module 110d may include a fourth laser supplying part 111d and a second lens array 120d. The fourth laser beam Ld of the fourth laser module 110d may be supplied through the fourth laser supplying part 111d. The fourth laser supplying part 111d may be connected to the outside to form a path for supplying the fourth laser beam Ld.

[0119] The second lens array 120d may guide the fourth laser beam Ld of the fourth laser module 110d to be incident on a portion of the edge region Re of the wafer W. Since the wafer W is rotated by the rotator 160, even if the fourth laser beam Ld is incident on only a portion of the edge region Re, the entire edge region Re may be heated by the rotation of the wafer W. Therefore, the fifth wafer cleaning apparatus 14 according to some embodiments may efficiently enhance the heating of the edge region Re at a relatively low cost.

[0120] The following will refer to Figure 3 and Fig.17 A sixth wafer cleaning apparatus 15 according to some embodiments is described. Repeated parts of the above-mentioned embodiments will be simplified or omitted. Fig.17 is a cross-sectional view for explaining a wafer cleaning apparatus according to some embodiments. Figure 3 and Fig.17 , the sixth wafer cleaning apparatus 15 may include a second reflector 130b, wherein the reflector 130 is used as the first reflector 130a.

[0121] The second reflector 130b may be located above the wafer W and may completely overlap the wafer W along the third direction Z. When the fourth laser beam Ld output by the fourth laser module 110d is reflected by the upper surface Wu of the wafer W, the second reflector 130b may reflect the reflected fourth laser beam Ld to be incident on the upper surface Wu of the wafer W again. Therefore, the heating efficiency of the fourth laser beam Ld on the upper surface Wu of the wafer W may be significantly improved. In addition, the fourth laser beam Ld may be prevented from being reflected and damaging other components of the sixth wafer cleaning apparatus 15. Therefore, the durability of the sixth wafer cleaning apparatus 15 may also be improved.

[0122] In the following, reference will be made to Figures 18 to 20 A first wafer cleaning apparatus 10 according to some embodiments is described. Repeated parts of the above embodiments will be simplified or omitted. Fig.18 is a perspective view for explaining a laser module of a wafer cleaning apparatus according to some embodiments. Fig.19 is used to explain Fig.18 A view of the arrangement of laser modules irradiating the laser. Fig. 20 Is used to explain the Fig.19 A view of the distribution of lasers. Figures 18 to 20 , the wafer cleaning apparatus according to some embodiments may include a fifth laser module 110 e .

[0123] The fifth laser module 110e may include a plurality of laser sources Le. Each laser source Le may output a laser beam L. The laser sources Le may irradiate the laser beam L in the same direction through the fifth laser module 110e.

[0124] The fifth laser module 110 e may include a plurality of fifth laser supplying portions 111 e . The plurality of fifth laser supplying portions 111 e may correspond to the plurality of laser sources Le, respectively. The plurality of fifth laser supplying portions 111 e may be aligned and guided by a laser supplying portion guide 117 .

[0125] The laser source Le can be arranged as follows Fig.19 As shown. In an embodiment, the arrangement of the laser sources Le may be symmetrical. In addition, the outputs of the plurality of laser sources Le may be adjusted individually.

[0126] Therefore, if Fig. 20 As shown, the laser distribution Le_p may have a somewhat uniform distribution as from a single laser source. The wafer cleaning apparatus according to the present embodiment may use a plurality of laser sources Le to more strongly heat the wafer W. This can significantly improve the etching rate of the wafer W.

[0127] Fig.21 is a graph of various heating profiles for wafer cleaning equipment according to some embodiments. Fig.21 , the above-mentioned wafer cleaning apparatus can keep the central region Rc and the edge region Re uniformly heated, as in the first distribution P1, can increase the heating of the central region Rc relative to the edge region Re, as in the second distribution P2, or can increase the heating of the edge region Re relative to the central region Rc, as in the distribution P3. That is, the degree of heating of the central region Rc and the edge region Re can be freely adjusted according to the purpose and need. This makes it possible to variously adjust the etching rates of the central region Rc and the edge region Re and accurately etch the wafer W.

[0128] As a summary and review, a wafer cleaning apparatus according to one or more embodiments can easily adjust the difference in etching rate across a wafer by controlling the distribution of a laser beam that heats the wafer.

[0129] Example embodiments have been disclosed herein, and although specific terms are employed, they are used and interpreted in a general and descriptive sense only, and not for purposes of limitation. In some cases, as will be apparent to one of ordinary skill in the art at the time of filing this application, features, characteristics, and / or elements described in conjunction with a particular embodiment may be used alone or in combination with features, characteristics, and / or elements described in conjunction with other embodiments, unless otherwise specifically noted. Therefore, it will be understood by those skilled in the art that various changes in form and detail may be made without departing from the spirit and scope of the invention as set forth in the appended claims.

Claims

1. A wafer cleaning device, comprising: a housing to be positioned adjacent to the wafer; a hollow region, the hollow region being within the housing; a laser module, the laser module being located in the housing and outputting a laser beam, the laser beam being output into the hollow region; a reflector that reflects the laser beam along a surface of the housing that defines the hollow region; as well as a transparent window covering an upper portion of the hollow region and transmitting the laser beam so that the laser beam is incident on the entire lower surface of the wafer, The distribution of the laser beam incident on the entire lower surface of the wafer includes a first region having a first intensity and a second region having a second intensity greater than the first intensity.

2. The wafer cleaning apparatus according to claim 1, wherein: The laser module comprises: a laser supplying section that supplies the laser beam, and An aspherical lens transforms the distribution of the laser beam.

3. The wafer cleaning device according to claim 2, in, The aspherical lens adjusts the width of the laser beam to be greater than the width of the transparent window so that the outermost portion of the laser beam is reflected by the reflector before being incident on the transparent window.

4. The wafer cleaning apparatus according to claim 2, wherein: The aspheric lens includes a first lens and a second lens, and The distance between the first lens and the second lens is adjustable to control the distribution of the laser beam.

5. The wafer cleaning apparatus according to claim 1, wherein: The distribution of the laser beam includes: a first laser beam having a uniform distribution in the first region and the second region, and A second laser beam, wherein the second laser beam is only in the second area.

6. The wafer cleaning apparatus according to claim 5, wherein: The laser module comprises: an aspherical lens that transforms the distribution of the first laser beam into the uniform distribution, and An axicon lens converts the distribution of the second laser beam into a ring shape.

7. The wafer cleaning device according to claim 5, further comprising: A rotator rotates the wafer, wherein the second laser beam heats a portion of the lower surface of the wafer.

8. The wafer cleaning apparatus according to claim 5, wherein: The laser module includes an anamorphic optical system that tilts the distribution of the second laser beam.

9. The wafer cleaning apparatus according to claim 5, wherein: The position and angle of the second laser beam are adjustable.

10. The wafer cleaning apparatus according to claim 5, wherein: The laser module further includes a beam splitter that splits a source laser beam to generate the first laser beam and the second laser beam.

11. The wafer cleaning apparatus according to claim 5, wherein: Before reaching the lower surface of the wafer, a distribution of the first laser beam and a distribution of the second laser beam are individually adjustable. 12 . The wafer cleaning apparatus according to claim 1 , further comprising an auxiliary laser module which provides an auxiliary laser beam to a portion of an upper surface of the wafer. 13 . The wafer cleaning apparatus according to claim 12 , further comprising an upper reflector overlapping the wafer and reflecting the laser beam reflected from the wafer back onto the upper surface of the wafer.

14. The wafer cleaning apparatus according to claim 1, wherein: The first region is incident on a central region of the wafer, and The second region is incident on an edge region of the wafer surrounding the central region.

15. A wafer cleaning device, comprising: a housing to be positioned adjacent to the wafer; a hollow region, the hollow region being within the housing; a laser module, the laser module being located in the housing and outputting a laser beam, the laser beam being output into the hollow region; a reflector that reflects the laser beam along a surface of the housing that defines the hollow region; as well as a transparent window covering an upper portion of the hollow region and transmitting the laser beam so that the laser beam is incident on the entire lower surface of the wafer, The distribution of the laser beam incident on the entire lower surface of the wafer includes a central region having a first intensity and an edge region having a second intensity different from the first intensity.

16. The wafer cleaning apparatus according to claim 15, wherein: The second intensity is greater than the first intensity.

17. The wafer cleaning apparatus according to claim 16, wherein: The distribution of the laser beam provides uniform heating to the entire lower surface of the wafer.

18. The wafer cleaning apparatus according to claim 15, wherein: The laser module includes a plurality of laser sources.

19. A wafer cleaning device, comprising: a housing to be positioned adjacent to a wafer, the wafer comprising a first central region and a first edge region surrounding the first central region; a hollow region, the hollow region being within the housing; a laser module, the laser module being located in the housing and irradiating the wafer with a laser beam; a reflector that reflects the laser beam along a surface of the housing that defines the hollow region; as well as a transparent window covering an upper portion of the hollow region and transmitting the laser beam, The distribution of the laser beam irradiating the wafer includes a second central region having a first intensity and a second edge region having a second intensity greater than the first intensity.

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