Wafer drying apparatus, semiconductor cleaning apparatus, and wafer drying method

Abstract

The application discloses a wafer drying device, a semiconductor cleaning device and a wafer drying method. The device comprises a drying tank, a spraying plate arranged at the top of the drying tank and used for spraying a drying atmosphere into the drying tank during the drying process, a supporting plate arranged at the bottom of the drying tank and connected with the side wall of the drying tank, a supporting component arranged on the supporting plate and used for supporting a wafer to be dried, a first through hole penetrating through the supporting component in the vertical direction and arranged on the supporting component and located at the contact area of the supporting component and the wafer, a water injection pipe used for injecting deionized water into the drying tank, and a suction device used for discharging the deionized water in the drying tank during the drying process, so that the wafer immersed in the deionized water is exposed to the liquid surface and the Marangoni effect occurs between the wafer and the drying atmosphere, and the drying atmosphere is sucked after the deionized water is discharged. The maintenance difficulty of the drying tank is reduced, and the drying effect of the contact area of the wafer is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor equipment, more particularly, to a wafer drying device, a semiconductor cleaning equipment and a wafer drying method. BACKGROUND

[0002] With the continuous development of IC semiconductor manufacturing technology, the feature size of semiconductor devices is continuously reduced, and the demand for cleaning process continues to increase. At present, the mainstream process is in 65-28 nanometers. The slot cleaning equipment has an irreplaceable advantage because it can batch process wafers while meeting the process effect. Efficient drying process has a significant use on the overall effect of wafer process and the production capacity of the machine.

[0003] As shown in Figure 1 and Figure 2 , the drying slot mechanical arm of the existing cleaning machine includes a support component 4 (Combs) and a lifting component 1 (Lifter), wherein the support component 4 is fixed on the lifting component 1 by screws 5, and the support component 4 is provided with support teeth 3 for supporting the wafer 2. The drying slot mechanical arm is used for supporting and lifting the wafer (the lifting is controlled by the Lifter body motor, Figure 1 not shown).

[0004] The drying method based on the drying slot mechanical arm includes:

[0005] Step 1. As shown in Figure 3 , the wafer 2 to be dried is placed on the drying slot mechanical arm by the wafer conveying mechanical arm, and then enters the drying slot 6 filled with deionized water (DIW);

[0006] Step 2. As shown in Figure 4 , during the drying process, the motor controls the lifting component 1 to slowly speed up (<10mm / s) to expose the water surface at the bottom of the support component 4. In this process, the spray plate 7 sprays IPA (isopropyl alcohol) steam, which gradually replaces the water on the surface of the wafer 2 by using the Marangoni effect. After the evaporation of IPA, the wafer 2 surface achieves the effect of dryness without water (Marangoni drying method is to use the different surface tension of isopropyl alcohol and deionized water to absorb the water droplets on the wafer surface back into the tank, to achieve the effect of drying the wafer surface).

[0007] Step 3. As shown in Figure 5 , the water in the drying slot is drained, and finally the nitrogen gas is sprayed out by the spray plate 7 and the nitrogen gas spraying pipe 8 to blow dry the area not easy to dry at the contact point of the wafer 2 and the support component 4, realizing the complete drying of the wafer 2.

[0008] However, in the prior art, the height of the drying tank is high, and the maintenance is difficult and the cost is high. Moreover, because the contact area between the wafer 2 and the support teeth 3 of the support member 4 is small, it is difficult for the N2-driven IPA vapor to enter the contact area, and thus part of the water is easily left in the contact area between the wafer surface and the support teeth 3 after the process, which affects the process effect. SUMMARY

[0009] The purpose of the present application is to provide a wafer drying device, a semiconductor cleaning equipment and a wafer drying method, which can reduce the maintenance difficulty of the drying tank and improve the drying effect.

[0010] To achieve the above-mentioned purpose, in a first aspect, the present application provides a wafer drying device, comprising:

[0011] a drying tank;

[0012] a spray plate arranged at the top of the drying tank and used for spraying a drying atmosphere into the drying tank during the drying process;

[0013] a support plate arranged at the bottom of the drying tank and connected with the side wall of the drying tank;

[0014] a support member arranged on the support plate, the support member being used for supporting a wafer to be dried, the support member being provided with a first through hole penetrating the support member in the vertical direction, the first through hole being located in the contact area between the support member and the wafer, and the upper space and the lower space of the support plate being communicated through the first through hole;

[0015] a water injection pipe communicated with the drying tank, the water injection pipe being used for injecting deionized water into the drying tank;

[0016] a suction device communicated with the bottom of the drying tank through a drain pipe, the suction device being used for discharging the deionized water in the drying tank during the drying process, so that the wafer immersed in the deionized water is exposed to the liquid surface and the Marangoni effect occurs between the wafer and the drying atmosphere, and the suction device is used for sucking the drying atmosphere after the deionized water is discharged, so that the drying atmosphere flows from the upper space of the support plate to the lower space of the support plate through the first through hole and is discharged, thereby drying the wafer.

[0017] In a second aspect, the present application provides a semiconductor cleaning equipment, comprising the wafer drying device of the first aspect.

[0018] In a third aspect, the present application further provides a wafer drying method applied to the wafer drying device of the first aspect, the wafer drying method comprising:

[0019] Place the wafer to be dried on the support member, inject deionized water into the drying tank through the injection pipe, and make the wafer to be dried completely immersed in the deionized water;

[0020] Inject a dry atmosphere into the drying tank through the injection plate, and at the same time, open the suction device to drain water, so that the liquid level of the deionized water drops and exposes the wafer, the dry atmosphere and the deionized water on the surface of the wafer have a marangoni effect, and the deionized water on the surface of the wafer is replaced by the dry atmosphere;

[0021] When the deionized water is completely drained from the drying tank, continue to inject a dry atmosphere and a blow-drying gas into the drying tank through the injection plate for a first set time, and continue to extract the dry atmosphere and the blow-drying gas through the suction device during the first set time;

[0022] Stop injecting the dry atmosphere and continue to inject the blow-drying gas through the injection plate to blow-dry the wafer for a second set time, and extract the residual dry atmosphere and blow-drying gas through the suction device during the second set time, to complete the drying of the wafer.

[0023] The beneficial effects of the present application are:

[0024] The present application uses a support plate fixed to the bottom of the drying tank and a support member arranged on the support plate to support the wafer, and a suction device in communication with the bottom of the drying tank, which replaces the traditional lifting type drying tank mechanical hand structure through the combination of the support member and the suction device. During the liquid drainage process, the water level in the tank is stably lowered by the suction device instead of the marangoni effect caused by the existing lifting member driving the wafer to gradually rise, thereby simplifying the mechanical structure of the drying tank. Since the lifting member is omitted, the height of the drying tank is reduced, and the maintenance difficulty and cost of the drying tank device are effectively reduced. At the same time, by arranging the first through hole near the contact area between the support member and the wafer, when the suction device sucks the dry atmosphere after the drying tank is drained, the airflow flows through the first through hole on the support member, accelerates the replacement of water and dry atmosphere in the contact area between the wafer and the support member, reduces the moisture residue in the contact area of the wafer, and improves the process effect of drying.

[0025] The device of the present application has other characteristics and advantages, which will be apparent or will be described in detail in the accompanying drawings and subsequent specific embodiments incorporated herein, which together serve to explain the specific principles of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0026] The above and other objects, features and advantages of the present application will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which like reference characters refer to like parts throughout the figures, and in which:

[0027] Figures 1-2 A structural diagram of a conventional drying tank robot is shown.

[0028] Figures 3-5 A step demonstration diagram of a conventional wafer drying process by a drying tank robot is shown.

[0029] Figure 6 A side view of a wafer drying apparatus along a second direction according to an embodiment of the present application is shown.

[0030] Figure 7 A side view of a wafer drying apparatus along a first direction according to an embodiment of the present application is shown.

[0031] Figure 8 A top view of a support plate and support members in a wafer drying apparatus according to an embodiment of the present application is shown.

[0032] Figure 9 A side view of a support plate and support members in a wafer drying apparatus along a second direction according to an embodiment of the present application is shown.

[0033] Figure 10 A side view of a support plate and support members in a wafer drying apparatus along a first direction according to an embodiment of the present application is shown.

[0034] Figures 11-14 A step demonstration diagram of a wafer drying tank method according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0035] The present application will now be described in greater detail in connection with the accompanying drawings. Although preferred embodiments of the present application are shown in the drawings, it should be understood that the present application can be practiced with various changes, modifications, additions and omissions without departing from the scope thereof, which is defined by the appended claims. It is therefore intended that the present application not be limited by the illustrative embodiments set forth in the following detailed description and the drawings.

[0036] Figure 6 A side view of a wafer drying apparatus along a second direction according to an embodiment of the present application is shown, Figure 7 A side view of a wafer drying apparatus along a first direction according to an embodiment of the present application is shown.

[0037] As Figure 6 and Figure 7As shown, a wafer drying device comprises:

[0038] a drying tank 101;

[0039] a spraying plate 102, which is arranged on the top of the drying tank 101 and used for spraying a drying atmosphere into the drying tank 101 during the drying process;

[0040] a supporting plate 103, which is arranged on the bottom of the drying tank 101 and connected with the sidewall of the drying tank 101;

[0041] a supporting component 105, which is arranged on the supporting plate 103 and used for supporting the wafer 104 to be dried, and a first through hole 110, which penetrates the supporting component 105 in the vertical direction, is arranged on the supporting component 105, the first through hole 110 is located at the contact area between the supporting component 105 and the wafer 104, and the space above the supporting plate 103 and the space below the supporting plate 103 are communicated through the first through hole 110;

[0042] a water injection pipe 107, which is communicated with the drying tank 101 and used for injecting deionized water into the drying tank 101;

[0043] a suction device 109, which is communicated with the bottom of the drying tank 101 through a drain pipe 108 and used for discharging the deionized water in the drying tank 101 during the drying process, so that the wafer 104 immersed in the deionized water is exposed to the liquid surface and the Marangoni effect occurs between the wafer 104 and the drying atmosphere, and the suction device 109 is used for sucking the drying atmosphere after the deionized water is discharged, so that the drying atmosphere flows from the space above the supporting component 105 to the space below the supporting plate 103 through the first through hole 110 and is discharged, thereby drying the wafer 104.

[0044] Specifically, the support plate 103 fixed on the bottom of the drying tank 101 and the support components 105 arranged on the support plate 103 are used to support the wafer 104, and the suction device 109 is arranged in communication with the bottom of the drying tank 101. The combination of the support components 105 and the suction device 109 replaces the traditional lifting type drying tank 101 mechanical hand structure. In the liquid drainage process, the suction device 109 is used to make the water level in the tank drop steadily instead of the existing lifting piece driving the wafer 104 to gradually rise to perform the Marangoni effect, thereby simplifying the mechanical structure of the drying tank 101. Since the lifting piece is omitted, the height of the drying tank 101 is reduced, and the maintenance difficulty and cost of the drying tank 101 device are effectively reduced. Meanwhile, the first through holes 110 penetrating through the support components 105 are arranged in the contact area between the support components 105 and the wafer, and the suction device 109 can make the drying atmosphere flow from top to bottom in one direction during the air jet drying process, so that the airflow flows through the first through holes 110, accelerates the replacement of water and drying atmosphere in the contact area between the wafer 104 and the support components 105, reduces the moisture residue in the contact area, and improves the drying effect.

[0045] The liquid / gas drainage pipeline composed of the drain pipe 8 and the suction device 109 can be arranged in one or multiple paths according to actual needs, for example, three paths.

[0046] As shown in Figures 8-10 In the embodiment, the support plate 103 is provided with a plurality of second through holes 106 and a plurality of third through holes 112 penetrating through the support plate in the vertical direction, the third through holes 112 are in communication with the first through holes 110, and the second through holes 106 are distributed on both sides of the support components 105.

[0047] As shown in Figure 8 In the embodiment, preferably, the diameters of the third through holes 112 and the first through holes 110 are the same, and the diameter of the first through holes 110 is less than 2 mm. The diameter of the second through holes is 1-5 mm, and the spacing between the second through holes is 1-10 mm. One to two rows of second through holes 106 are arranged on both sides of each support component 105, the spacing between the second through holes 106 is 1-10 mm, the number of the second through holes 106 is 15-50, and the diameter of the second through holes 106 is 1-5 mm.

[0048] The second through hole 106 is arranged, on one hand, to accelerate the liquid discharge process, so that the deionized water quickly flows from the upper space of the support plate 103 to the lower space of the support plate 103 and is discharged, and on the other hand, the second through hole 106 is arranged near the support tooth, when the suction device 109 sucks the dry atmosphere and the blow-drying gas after the water discharge of the drying tank 101 is completed, the airflow can flow through the second through hole 106 on the support plate 103 and the first through hole 110 on the support component 105 at the same time, because the diameter of the through hole is small, the flow rate of the airflow at the contact area of the wafer 104 and the support component 105 is fast, so that the replacement of the water at the contact area of the wafer 104 and the support component 105 by the dry atmosphere is accelerated, the water residue at the contact area is reduced, and the process effect of drying is improved.

[0049] In the embodiment, the support component 105 is multiple, the multiple support components 105 are arranged on the support plate along the first direction at intervals, different support components 105 are used to support different positions of the bottom edge of the wafer 104, the multiple wafers 104 are vertically arranged on the multiple support components 105 and arranged along the second direction perpendicular to the first direction, the height of the multiple support components 105 corresponds to the height of the supported position of the bottom edge of the wafer 104 (for example, different heights are set for the two sides and the middle), and the height of the top of the support component 105 is preferably 1-15 mm.

[0050] The support component 105 is comb-shaped, the top end of the support component 105 is provided with multiple support teeth along the second direction, the two sides of the support tooth have support inclined surfaces, and the opposite support inclined surfaces of adjacent two support teeth jointly support the two sides of the edge of the wafer 104; the first through hole 110 is arranged between the adjacent support teeth and communicates the space above the support plate 103 and the space below the support plate 103. The support component 105 is fixed on the support plate 103 through the first connecting piece, and the first connecting piece is a screw 111.

[0051] In the embodiment, the support plate 103 and the support component 105 are preferably made of any non-metallic material capable of supporting 50 wafers 104, so that batch processing drying of the wafers is realized.

[0052] In the embodiment, the support plate 103 is fixed on the side wall of the drying tank 101 through the second connecting piece, and the height of the support plate 103 is located at one third of the height of the side wall of the drying tank 101. The second connecting piece can be a screw, a fixing block or any connecting piece.

[0053] In the embodiment, the dry atmosphere is IPA gas driven by nitrogen, the IPA gas can cause the Malan-Goni effect with the deionized water on the surface of the wafer, replace the residual deionized water on the surface of the wafer, realize the drying of the surface of the wafer, and the blow-drying gas is nitrogen.

[0054] The embodiment of the present application also provides a semiconductor cleaning equipment comprising the wafer drying device in the above embodiment.

[0055] The semiconductor cleaning equipment may also include all other components of existing wafer batch processing tank cleaning equipment, such as wafer handling robots, which will not be described in detail here.

[0056] This invention also proposes a wafer drying method, applied to the wafer drying apparatus of the above embodiments, the wafer drying method comprising:

[0057] S101: As Figure 11 As shown, the wafer 104 to be dried is placed on the support component 105, and deionized water is injected into the drying tank 101 through the liquid injection pipe 107 so that the wafer 104 to be dried is completely immersed in the deionized water.

[0058] S102: As Figure 12 As shown, a drying atmosphere (IPA atmosphere driven by nitrogen) is sprayed into the drying tank 101 through the spray plate 102. At the same time, the suction device 109 is turned on and the water is drained at the set drainage flow rate, so that the liquid level of deionized water drops and exposes the wafer 104. The IPA atmosphere and the deionized water on the surface of the wafer 104 undergo the Marangoni effect, and the deionized water on the surface of the wafer 104 is replaced by IPA.

[0059] In this process, the level of deionized water is gradually lowered by controlling the drainage flow rate, thus gradually exposing wafer 104.

[0060] S103: As Figure 13 As shown, after the deionized water is completely discharged from the drying tank 101, IPA atmosphere and drying gas (nitrogen) are simultaneously sprayed into the drying tank 101 through the spray plate 102 for a first set time, and the IPA atmosphere and nitrogen are continuously extracted through the suction device 109.

[0061] S104: As Figure 14 As shown, the spray plate 102 stops spraying IPA atmosphere and continues to spray nitrogen to dry the wafer 104 for a second set time. During this period, the residual IPA atmosphere and nitrogen are extracted by the suction device 109 to complete the drying.

[0062] The suction device 109 provides a stable drainage flow rate, allowing the liquid level in the drying tank 101 to drop steadily during the drainage process, replacing the original lifting mechanism that drives the wafer 104 to rise. This allows the water and IPA atmosphere in the drying tank to be discharged through the first through hole 110 on the support component 105 and the second through hole 106 on the support plate 103. During the drying stage, the IPA atmosphere is discharged from the second through hole 106, the first through hole 110, and the third through hole 112. The IPA atmosphere can further replace the water with IPA in the contact area between the wafer 104 and the support component 105, and nitrogen can further dry the contact area, improving the drying process effect.

[0063] In summary, the present application replaces the existing lifting structure with the suction device 109 and the support component 105, simplifies the mechanical structure of the drying tank 101, reduces the height of the drying tank 101, and reduces the difficulty of maintenance. Through the new design of the drying tank and components, the process step of wafer drying is improved. After the end of the drainage of the drying tank 101, the IPA / N2 atmosphere can be sucked through the through holes on the support plate 103 and the support component 105 by the bottom suction device 109, thereby accelerating the IPA-water replacement of the contact area between the wafer 104 and the fixed support, reducing the water residue in the contact area, making the drying effect more thorough, and improving the drying effect.

[0064] The above has described the embodiments of the present application, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes are obvious to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A wafer drying method applied to a wafer drying apparatus, the wafer drying apparatus comprising: A drying tank; A spray plate is arranged on the top of the drying tank for spraying dry atmosphere into the drying tank during the drying process; A support plate is arranged on the bottom of the drying tank and connected with the side wall of the drying tank; a support component is arranged on the support plate, which is used for supporting the wafer to be dried; the support component is provided with a first through hole penetrating the support component in the vertical direction, which is located in the contact area of the support component and the wafer, and the upper space and the lower space of the support plate are communicated through the first through hole; a water injection pipe is communicated with the drying tank, which is used for injecting deionized water into the drying tank; a suction device is communicated with the bottom of the drying tank through a drain pipe; The wafer drying method comprises: Placing the wafer to be dried on the support component, injecting deionized water into the drying tank through the water injection pipe, and making the wafer to be dried completely immersed in the deionized water; Spraying dry atmosphere into the drying tank through the spray plate, and simultaneously starting the suction device to drain water, so that the liquid level of the deionized water drops and exposes the wafer; the dry atmosphere and the deionized water on the surface of the wafer produce the Marangoni effect, and the deionized water on the surface of the wafer is replaced by the dry atmosphere; After the deionized water is completely drained from the drying tank, continue to spray dry atmosphere and dry gas into the drying tank through the spray plate for a first set time, and continue to extract the dry atmosphere and the dry gas through the suction device, so that the gas flow of the dry atmosphere and the dry gas flows from the upper space of the support plate to the lower space of the support plate through the first through hole arranged near the contact area of the support component and the wafer, and is then discharged; Stop spraying the dry atmosphere and continue to spray the dry gas to dry the wafer for a second set time, and extract the residual dry atmosphere and dry gas through the suction device to complete the drying of the wafer.

2. The wafer drying method according to claim 1, wherein The support plate is provided with a plurality of second through holes and a plurality of third through holes penetrating the support plate in the vertical direction, the third through holes are communicated with the first through holes, and the second through holes are distributed on at least two sides of the support component.

3. The wafer drying method according to claim 1, wherein The support component is a plurality of support components, which are arranged on the support plate in a first direction, different support components are used for supporting different positions of the edge of the wafer, and a plurality of wafers are vertically arranged on the plurality of support components and arranged in a second direction perpendicular to the first direction.

4. The wafer drying method according to claim 3, wherein The support component is comb-shaped, the top end of the support component is provided with a plurality of support teeth in the second direction, the two sides of the support tooth have support inclined surfaces, and the opposite support inclined surfaces of adjacent two support teeth jointly support the two sides of the edge of the wafer; The first through hole is arranged between the adjacent two support teeth.

5. The wafer drying method according to claim 2, wherein The diameter of the first through hole is less than 2mm; The diameter of the second through hole is 1-5mm, and the spacing between the second through holes is 1-10mm.

6. The wafer drying method according to claim 1, wherein The material of the support plate and the support component is non-metal material, and the support component is arranged on the support plate through a first connecting piece.

7. The wafer drying method according to claim 1, wherein The support plate is fixedly connected with the side wall of the drying groove through a second connecting piece, and the height of the support plate is located at one third of the height of the side wall of the drying groove.

8. The wafer drying method according to claim 1, wherein The drying atmosphere is nitrogen-driven IPA gas.

9. A semiconductor cleaning apparatus characterized by comprising: The application further provides a wafer drying device applying the wafer drying method.

Images