TW201819053A - Coating method, coating device, and storage medium - Google Patents

Abstract

[Problem] When a coating liquid is applied to a wafer, particles are removed in a short time, and defects in the coating film are more reliably suppressed. [Solution] Before supplying the coating liquid (102) to the wafer (W) carried into the coating apparatus, firstly, supply a diluent (100) to wet the surface of the wafer (W), and secondly, The surface of the wafer (W) is dry. Thereby, the particles (101) on the surface of the wafer (W) become easy to flow. In addition, when the surface of the wafer (W) is dried and the diluent (100) is supplied to the surface of the wafer (W), the cross section of the gas-liquid interface of the fluid accumulated in the diluent is rounded. Since the particles (101) can be pushed with a large force, the particles (101) can be removed more reliably in a short time. Therefore, when the coating liquid (102) is applied to the wafer (W) thereafter, the formation of plaque on the SOC film due to the adhesion of the particles (101) can be suppressed.

Description

Coating method, coating device and memory medium

[0001] The present invention relates to a technique for forming a coating film by supplying a coating liquid to the surface of a substrate.

[0002] As one of semiconductor manufacturing processes, there is a method of supplying a coating liquid to a semiconductor wafer (hereinafter referred to as a “wafer”) to form a coating film such as a photoresist film, an antireflection film, or an etching mask. Manufacturing process of SOC (Spin On Cap) film with carbon as the main component. In this process, a spin coating method is widely used. [0003] For example, an etching mask such as a SOC film is formed by forming a step pattern on a wafer and then covering the surface of the wafer. However, for example, there is an etching process in which a step pattern is formed on a wafer. In the case where particles generated in previous processes are attached to the surface of the wafer. Thereafter, when the coating liquid is supplied to the wafer and spin-coated, the spread of the coating liquid is hindered by the particles, and a comet-type spot (coma) with the particles as the core is formed on the coating film. . Since semiconductor devices tend to be gradually miniaturized, when defects such as these occur in the coating film, it becomes the main cause of the decrease in yield. [0004] As a countermeasure against such coating defects, for example, as described in Patent Document 1, before coating the coating liquid, a diluent is supplied to the wafer, the surface is cleaned, and particles are removed to maintain the crystal. From the viewpoint of productivity, it is required to efficiently remove particles in a shorter period of time. In addition, from the viewpoint of avoiding an increase in the size of the device, cleaning of particles in the module to be coated is required. [Prior Art Document] [Patent Document] [0005] [Patent Document 1] Japanese Patent Laid-Open No. 2006-208456

[Problems to be Solved by the Invention] 0006 [0006] The present invention has been made in view of such circumstances, and an object thereof is to provide a technique such as applying a coating liquid to a substrate to form a coating. In the case of fabric film, fine particles can be removed in a short period of time to prevent the occurrence of defects in the coating film. [Means to Solve the Problem] [0007] The coating method of the present invention is characterized by including: (i) a process of horizontally holding a substrate; (ii) a process of wetting the entire surface of the substrate by a processing liquid; (ii) A process of rotating the substrate around the vertical axis to dry the surface of the substrate; 后 thereafter, a process of supplying the cleaning liquid to the surface of the substrate while rotating the substrate around the vertical axis; and then, supplying a coating liquid The process of forming a coating film on the surface of a substrate. [0008] The memory medium of the present invention stores a computer program used in a coating device that supplies a coating liquid to a substrate that is horizontally held and rotated about a vertical axis to perform coating. The memory medium is characterized by a step group incorporated therein to perform the above-mentioned coating method. [0009] The coating device of the present invention is characterized by having: ： a substrate holding section for horizontally holding the substrate; a rotation mechanism for rotating the substrate holding section about a vertical axis; a coating liquid nozzle for A coating liquid is supplied to a substrate held by the substrate holding portion; a processing liquid nozzle supplies a processing liquid to a substrate held by the substrate holding portion; a cleaning liquid nozzle supplies a washing liquid to a substrate held by the substrate holding portion; The cleaning solution and the control unit perform the following steps: a step of holding the substrate horizontally; a step of wetting the entire surface of the substrate by a processing liquid; and then, rotating the substrate about a vertical axis to make the substrate Surface drying step; thereafter, a step of supplying a cleaning solution to the surface of the substrate while rotating the substrate around a vertical axis; and a step of supplying a coating solution to the surface of the substrate to form a coating film. [Effects of the Invention] [0010] In the present invention, before the coating liquid is supplied to the substrate, the processing liquid is supplied to the substrate to wet the surface of the substrate, and then the surface of the substrate is dried. Thereby, the particles become easily detached from the surface of the substrate. In addition, in order to dry the surface of the substrate, when the cleaning liquid is continuously supplied to the surface of the substrate, the particles can be pushed by the gas-liquid interface with a large force, and more reliably in a short time Perform removal. Therefore, it is possible to suppress the formation of specks on the coating film due to the adhesion of particles when the coating liquid is applied to the substrate thereafter. Furthermore, according to the coating apparatus of the present invention, since the substrate has a cleaning function, it is not necessary to separately install a cleaning apparatus.

[0012] As an example of a coating apparatus according to an embodiment of the present invention, a coating apparatus for forming a SOC film on a wafer W will be described using FIG. 1. The coating device includes a cup module 1 and a cup module 1 including a spin chuck 11 that is a substrate holding portion that holds the central portion of the back surface of the wafer W and holds the wafer horizontally. The rotary chuck 11 is connected to the rotary mechanism 13 through the shaft portion 12 from below, and can be rotated around the vertical axis by the rotary mechanism 13. [0013] A circular plate 14 is provided below the spin chuck 11 so as to surround the shaft portion 12 through a gap. The circular plate 14 has three through holes 17 formed at equal intervals in the circumferential direction, and each of the through holes 17 is provided with a lift pin 15. The lift pin 15 is configured to be raised and lowered by the lift mechanism 16, and the wafer W is transferred between the transfer arm outside the coating apparatus and the rotary chuck 11 by the lift of the lift pin 15. [0014] A cup body 2 is provided so as to surround the rotary chuck 11. The cup body 2 receives the liquid discharged from the rotating wafer W by scattering or dropping, and discharges the liquid to the outside of the coating device. The cup body 2 is provided with a ring-shaped mountain-shaped guide 21 provided in a mountain shape in cross section around the circular plate 14 and extends downward from the outer peripheral end of the mountain-shaped guide 21. An annular vertical wall 23 is provided. The mountain-shaped guide portion 21 guides the liquid spilled from the wafer W toward the outside and below the wafer W. [0015] Furthermore, a vertical cylindrical portion 22 is provided to surround the outer side of the mountain-shaped guide portion 21, and an upper guide portion 24 extends obliquely from the upper edge of the cylindrical portion 22 toward the inside and upward. The upper guide portion 24 is provided with a plurality of openings 25 in the circumferential direction. In the lower side of the tubular portion 22, a ring-shaped liquid receiving portion 26 having a recessed cross section is formed below the mountain-shaped guide portion 21 and the vertical wall 23. The liquid receiving portion 26 is connected to a liquid discharge path 27 on the outer peripheral side, and is provided on the inner peripheral side of the liquid discharge path 27 in a shape protruding from below, and an exhaust pipe 28 is provided. In addition, a cylindrical portion 29 is provided so as to extend upward from the peripheral edge of the proximal end side of the upper guide portion 24, and an inclined wall 30 is provided so as to protrude from the upper edge of the cylindrical portion 29 toward the inside and upward. The liquid scattered by the rotation of the wafer W is received by the cylindrical portion 29, the inclined wall 30, the upper guide portion 24, and the vertical wall 23, and is introduced into the liquid discharge path 27. [0016] The coating apparatus is provided with a coating liquid nozzle 3 for supplying a coating liquid to the wafer W, and the coating liquid dissolves an organic material that becomes a precursor substance of the SOC film in a solvent. The coating liquid nozzle 3 is connected to the coating liquid supply mechanism 32 via a coating liquid supply pipe 31. As the coating liquid, an organic material containing a carbon compound is used, for example, a liquid in which a polymer raw material having a structure of a polyethylene structure ((-CH _2- ) _n ) is dissolved in a solvent. [0017] The coating device includes a nozzle unit 6 provided with a diluent nozzle 4 for supplying a diluent, which is a solvent serving as a cleaning liquid and a processing liquid; and N ₂ The gas nozzle 5 supplies nitrogen (N ₂ gas) to the wafer W. The diluent nozzle 4 is connected to the diluent supply mechanism 42 via a diluent supply pipe 41. The diluent supply mechanism 42 is provided with a device such as a pump, a valve, and a filter, and is configured to discharge a predetermined amount of diluent from the front end of the diluent nozzle 4. The N ₂ gas nozzle 5 is connected to an N ₂ gas supply mechanism 52 via an N ₂ gas supply pipe 51. The N ₂ gas supply mechanism 52 is provided with a device such as a pump, a valve, a filter, and the like, and is configured to discharge N ₂ gas from the N ₂ gas nozzle 5. The coating liquid nozzle 3 and the nozzle unit 6 are each configured to move between the upper portion of the wafer W and the standby position outside the cup body 2 by a moving mechanism (not shown). [0018] The coating device is provided with a control unit 10 composed of, for example, a computer. The control unit 10 has a program storage unit. The program storage unit stores a program programmed in order to receive and deliver wafers W between the external transfer arm and the rotary chuck 11 or rotate the rotary chuck 11. , Supply sequence of coating liquid, diluent and N ₂ gas. This program is stored in a storage medium such as a floppy disk, an optical disk, a hard disk, a MO (optical disk), or a memory card, and is installed in the control unit 10. [0019] Next, the operation of the embodiment of the present invention will be described with reference to the timing chart of FIG. 2 and the operation diagrams of FIGS. 3 to 10. The wafer W described above is transferred to the spin chuck 11 by the cooperation of an external transfer arm (not shown) and the lift pin 15. First, in order to make the directions of the wafers W coincide, as shown in FIG. 2 (a), the wafer W is rotated for 1 second from the time t ₀ at a rotation number of, for example, 2000 rpm. As shown in FIG. 3, the nozzle unit 6 is moved from the standby position, and the thinner nozzle 4 is moved to a position where the thinner, which is a processing liquid, is discharged toward the center of the wafer W. [0020] Next, FIG. 2 (a) as shown at time t _1, the number of rotations of the wafer W is maintained at 1000 rpm for the decline, and toward the wafer W, as shown in FIG 2 (b) and FIG. 4, From the time t ₁ to t ₂ , the diluent 100 is discharged at a flow rate of, for example, 75 sccm. As a result, the diluent 100 diffuses on the surface of the wafer W due to the centrifugal force, and the entire surface of the wafer W becomes wet. [0021] Next, FIG. 2 (a) as shown at time t _2, the number of rotations of the wafer W is maintained at 3000 rpm for rises, and FIG. 2 (c) and 5, the nozzle unit 6 is moved Then, the N ₂ gas nozzle 5 is moved to a position where the gas is discharged toward the center of the wafer W, and N ₂ gas is discharged. The time from time t ₂ to time t ₃ is 3 seconds. In the previous process, although the wafer W was in a state of being wetted by the diluent 100, the diluent was supplied by increasing the number of rotations of the wafer W and supplying N ₂ gas toward the surface of the wafer W. 100 will be thrown away to dry the surface of the wafer W. [0022] Before the wafer W is supplied, moisture is adsorbed on the surface. Although the fine particles are adhered to the surface of the wafer W, when viewed microscopically, we think that the particles are in a state of being adsorbed by the surface-like moisture of the wafer W. Therefore, in this example, when the diluent 100 is supplied to the center portion of the rotating wafer W to expand the diluent, the moisture adsorbed on the surface of the wafer W is washed away by the diluent 100. In addition, the number of rotations of the wafer W is increased to shake off the diluent 100, and the surface of the wafer W is dried by spraying N ₂ gas, whereby the particles attached to the surface of the wafer W are easily moved. Although the diluent 100 supplied at time t ₁ is a liquid for removing water on the surface of the wafer W, that is, a processing liquid, it expands due to the rotation of the wafer W, and it exerts flushing and adhesion to the crystal. A part of the particles on the surface of the circle W acts as a cleaning solution. [0023] Thereafter, to stop the discharge gas of N _2, the nozzle unit 6 is moved to the diluent nozzle 4 is moved toward the center of the wafer W is discharged cleaning liquid diluent i.e. position 100. Further, as shown in FIG. 2 (b) and FIG. 6, at time t _3, the number of rotations of the wafer W is maintained at 1000 rpm for the decline, and toward the wafer W, between 3 seconds from time t ₃ to _{t. 4} to For example, the diluent 100 is discharged at a flow rate of 75 sccm. [0024] As described above, on the wafer W after the process of drying the surface of the wafer W, the particles on the surface become easy to move. In addition, since the surface of the wafer W is dried, the particles are washed away in a state where the peripheral edge of the liquid of the diluent 100 spreading on the surface of the wafer W is rounded in a cross-sectional view. Next, at time t ₄ , the number of rotations of the wafer W is increased, and after 3 seconds from time t ₄ to time t ₅ , it is maintained at 3000 rpm. As shown in FIG. 7, the nozzle unit 6 is moved to make N ₂ gas. The nozzle 5 is moved to a position where gas is discharged toward the center of the wafer W, and N ₂ gas is discharged. Thereby, the diluent 100 on the surface of the wafer W is thrown away, and the surface of the wafer W is dried. Thereafter, the discharge of the N ₂ gas is stopped, the nozzle unit 6 is moved, and the diluent nozzle 4 is moved to a position where the diluent is discharged toward the center of the wafer W. [0025] Thereafter, at time t _5, the number of rotations of the wafer W is maintained at 1000 rpm for the decline, and 8, toward the wafer W, the cleaning liquid in this system from time t ₅ to t ₆ In 6 seconds, the diluent 100 is discharged at a flow rate of, for example, 75 sccm. Thereby, the diluent 100 diffuses on the surface of the wafer W after drying, and the particles remaining on the surface of the wafer W are pushed and removed by the gas-liquid interface. That is, in this example, the effect is performed twice as follows: moisture is removed from the surface of the wafer W and formed into a dried state, and secondly, the diluent 100 spreading along the surface of the wafer W In a state where the peripheral edge of the accumulated liquid was rounded in cross-section, the particles 101 were washed away. [0026] Thereafter, the nozzle unit 6 is retracted out of the wafer W, and the wafer W is rotated at a rotation number of 2000 rpm for 0.3 seconds, and then, the wafer W is rotated at a rotation number of 500 rpm for 0.2 seconds. Further, the coating liquid nozzle 3 is moved to a position where the coating liquid 102 is applied toward the center of the wafer W. From time t ₇ , the number of rotations of the wafer W is increased to maintain the number of rotations of 3000 rpm, and as shown in FIG. 2 (d) and FIG. 9, the coating liquid 102 is supplied for 1.5 seconds. Thereby, the coating liquid 102 supplied to the surface of the wafer W is diffused by centrifugal force to the entire surface of the wafer W wetted with the diluent. [0027] In the above-mentioned embodiment, before the coating liquid 102 is supplied to the wafer W carried into the coating apparatus, the diluent 100 is first supplied to wet the surface of the wafer W, and secondly, the wafer W is supplied. The surface is dry. Thereby, the water | moisture content on the surface of the wafer W is removed, and the particle 101 becomes easy to flow. Next, when the diluent 100 is supplied to the surface of the wafer W, since the gas-liquid interface of the diluent 100 diffuses on the surface of the wafer W, the gas-liquid interface can push the particles with a large force. Remove particles more reliably in a short time. Therefore, when the coating liquid 102 is applied to the wafer W after that, the formation of plaque on the SOC film due to the adhesion of the particles 101 can be suppressed. [0028] At this time, the entire surface of the wafer W is wetted with the diluent 100, and then, the surface of the wafer W is dried, and then the diluent 100 is supplied. As a result, as shown in a verification test described later, the particles are changed To be easily removed. This mechanism is estimated as follows. When the surface of the wafer W is wet, the surface of the wafer W is fused with the diluent 100. Therefore, the contact angle of the fluid of the diluent flowing through the surface of the wafer W becomes smaller, and as shown in FIG. 10, the gas-liquid interface of the diluent 100 becomes smooth. Therefore, when the diluent 100 diffuses on the surface of the wafer W, the force pushing the particles 101 from the side becomes weak, causing the particles to flow above the particles, and in particular, the area of the force outside the wafer W becomes weaker. This makes it easy to leave particles. [0029] In this regard, in a manner that the surface of the wafer W is dried, the water repellency of the surface of the wafer W is improved, and the contact angle of the accumulated liquid of the diluent flowing through the surface of the wafer W is increased. Therefore, as shown in FIG. 11, when the diluent 100 is supplied to the surface of the wafer W, the cross section of the accumulated liquid of the diluent 100 becomes round, and the particles 101 can be pushed from the side to the surface, and Even if it is pushed in the vicinity of the outer periphery of the wafer W, a strong force can be maintained. Therefore, it is estimated that the removal efficiency of the fine particles is improved. As a result, as shown in a verification test described later, even when the flow rate of the cleaning solution is reduced or the supply time of the cleaning solution is set to be short, the particles 101 can be efficiently removed. [0030] Further, before the wafer W will be supplied from the coating liquid 102 toward the wafer W between the time t ₅ to _{t. 6} of the supply time for supplying the diluent 100 is set to 6 seconds. Since drying is accelerated by injecting N ₂ gas toward the wafer W to promote vaporization, the temperature of the wafer W, especially the temperature of the area outside the wafer W, is facilitated by the vaporization cooling. If it falls, there exists a possibility that it may affect the drying time of a coating film, for example. Since the diluent 100 is supplied at normal temperature (25 ° C.), before the photoresist liquid is supplied to the wafer W, the supply time of the diluent 100 supplied to the wafer W is lengthened. The temperature of the wafer W, which is lowered by the blowing of the gas, returns to normal temperature. [0031] In the above embodiment, the process of supplying the diluent 100 to the rotating wafer W and the supply of N ₂ gas to the surface of the wafer W are repeated twice to dry the surface of the wafer W. The process of supplying the diluent 100 to the rotating wafer W and the process of supplying N ₂ gas to the surface of the wafer W and drying the surface of the wafer W may be performed once. [0032] As shown in the above embodiment, after the surface of the wafer W is dried, the diluent 100 is supplied to the wafer W, whereby the particles 101 can be pushed by the gas-liquid interface with a large force. . Therefore, since the process of supplying the diluent to the rotating wafer W and the process of supplying the N ₂ gas to the surface of the wafer W and drying the surface of the wafer W are repeated, the pushing at the gas-liquid interface can be increased. The number of times of the fine particles 101 makes it possible to more reliably remove the fine particles. In addition, the process of supplying the treatment liquid (cleaning liquid), ie, the diluent 100, to the rotating wafer W and the process of supplying N ₂ gas to the surface of the wafer W to dry the surface of the wafer W may be repeated three or more times. engineering. [0033] When the surface of the wafer W is dried, the wafer W may be dried by rotating the wafer W by rotating the wafer W, but as shown in the verification test 3 described later, After the diluent is supplied to the wafer W, the diluent is stopped to rotate the wafer W, and a nitrogen gas is supplied toward the wafer W, so that the particle removal rate can be improved even in a short drying time. Therefore, the processing time of the wafer W can be shortened. [0034] Furthermore, when the wafer W is first wetted, the supply time of the diluent, that is, the time to discharge the diluent, which is the processing liquid, may be set to be shorter than the time to discharge the diluent that becomes the cleaning liquid. For example, the time from the time t ₁ to t ₂ when the processing liquid is discharged as shown in FIG. 2 is set to 1 second, the time from the time t ₃ to t ₄ when the cleaning liquid is first discharged is 3 seconds, and the second The time from the time t ₃ to t ₄ at which the washing liquid is ejected twice is set to 6 seconds. As long as the processing liquid can be supplied in an amount sufficient to wet the surface of the wafer W, the inventors can obtain the following insights: in the case of shortening the supply time of the processing liquid, the removal performance does not occur. Variety. As a result, the processing time of the wafer W can be shortened. In addition, even when the processing liquid and the cleaning liquid are sequentially supplied, the discharge time of the processing liquid can be made shorter than the supply time of the cleaning liquid. [0035] In addition, since the processing liquid supplied to the wafer W only needs to remove the water on the surface of the wafer W, it may be, for example, alcohol. In addition, for example, TMAH (tetramethylammonium hydroxide) or APM cleaning treatment solution (ammonia / hydrogen peroxide / water mixed solution) can be used. Since these chemical liquids wet particles on the surface of the wafer W, the particles attached to the surface of the wafer W can be peeled off. Therefore, the particles can be removed more efficiently. In addition, since the method of supplying pure water to the surface of the wafer W and then drying it also has the effect of removing moisture, it can also be pure water. Furthermore, after the wafer W is carried in, a diluent may be used as the supplied processing liquid first, and after the wafer W is dried, for example, TMAH may be supplied as the cleaning liquid supplied to the wafer W, and thereafter, the crystal After the circle W was dried, a diluent was supplied as a washing liquid. The cleaning liquid may be a solvent for performing a pre-wetting treatment in which the coating liquid is easily diffused while the wafer W is in a wet state, and the same pretreatment as the cleaning liquid may be used for the processing liquid. Solvent for wet processing. [0036] In addition, when the processing liquid and the cleaning liquid are supplied to the wafer W, the processing liquid and the cleaning liquid may be discharged to the wafer W while the nozzle is moved in the circumferential direction of the wafer W, and The discharge positions of the processing liquid and the cleaning liquid are moved in the circumferential direction of the wafer W. The treatment liquid and the cleaning liquid may be the same chemical liquid such as a solvent, or different chemical liquids such as different solvents. [0037] When the supply of the drying-cleaning liquid is repeated a plurality of times, the rotation direction of the wafer W may be switched alternately between each time. When this method is applied to the embodiment described above, the rotation direction of the wafer between t ₃ -t ₄ and the rotation direction of the wafer W between t ₁ -t ₂ and t ₅ -t ₆ are Opposite each other. When the number of rotations of the wafer W becomes higher, the wafer W becomes easier to be cooled. Therefore, the number of rotations of the wafer W in the process of drying the wafer W is preferably 1000 to 3000 rpm. In addition, from the viewpoint of sufficiently drying the wafer W and suppressing the influence on productivity, the process of drying the wafer W (the time from the stop of the supply of the diluent to the start of the supply of the diluent) is 3 seconds to 6 Second is better. The time for supplying the cleaning liquid to the wafer W is preferably 3 seconds or more. [0038] The wafer W coated with the coating liquid may be a wafer W formed with a step pattern. In the process of forming a step pattern such as an etching process, particles are easily generated, and the wafer W after the step pattern is formed is liable to be adhered with particles. In addition, when the step pattern is formed on the wafer W, particles are likely to be caught in the step pattern and there is a problem that the particles are difficult to flow. As shown in the verification test to be described later, the present invention can also be used to obtain an effect even on a wafer W formed with a step pattern. The coating liquid may be a coating liquid for forming a photoresist film or an antireflection film. [Certification Test 1] The present inventors made various settings for the parameters such as the supply time of the diluent to the wafer, the rotation speed when the diluent was supplied, the flow rate of the diluent, and the cleaning method, and investigated The present invention was found to have an effect on particle removal efficiency. In the following, various verification tests related to the present invention and their results are described. In addition, the verification method also includes the method of the present invention. [Acquisition of Reference Example Materials] Polystyrene latex particles (PSL particles) with a diameter of 25 μm were attached to the surface of the inspection wafer W, and the coating device shown in the embodiment was rotated at a number of revolutions of 2000 rpm. The inspection wafer W was rotated for 1 second. Next, the inspection wafer W was rotated at a rotation number of 1000 rpm, and the diluent (OK73) was supplied at a flow rate of 75 ml / min for 12 seconds while facing the center of the inspection wafer W. Thereafter, the inspection wafer W was rotated at a rotation number of 2000 rpm for 4.5 seconds, rotated at a speed of 100 rpm for 1 second, and rotated at a speed of 1500 rpm for 15 seconds, and the wafer W after the surface was dried was used as a reference example. [Certification Test 1-1] The following example is referred to as the certification test 1-1. The time period during which the diluent is supplied while the inspection wafer W is rotated is set to 18 seconds. Do the same. [Certification Test 1-2] The following example is referred to as the certification test 1-2: except that the inspection wafer W is rotated while the diluent is supplied while the number of rotations of the wafer W is set to 2000 rpm, Others are treated in the same way as the verification test 1-1. [Certification Test 1-3] The following example is referred to as the certification test 1-3: except that the inspection wafer W is rotated while the diluent is supplied while the number of rotations of the wafer W is set to 3000 rpm, Others are treated in the same way as the verification test 1-1. [Certification Test 1-4] The following example is set as the certification test 4: except that the flow rate of the diluent when the diluent is supplied while rotating the inspection wafer W is set to 150 ml / min. The verification test 1-1 is also processed. [0041] For the reference example and each verification test 1-1 to 1-4, the number of adhesion (the number of adhesion before the test) of PSL particles (diameter 1 μm or more) in the inspection wafer W before being transferred to the coating apparatus The difference between the number of adhesion (the number of adhesions after the test) with the PSL particles (diameter 1 μm or more) in the inspection wafer W after each treatment, and the removal rate ((the number of adhesions before the test-the number of adhesions after the test) / test Number of front attachments × 100)%. [0042] FIG. 12 shows the results, and shows the removal rate of PSL particles in the reference examples and verification tests 1-1 to 1-4. In the reference example, the removal rate of PSL particles was 10.5%. In addition, the removal rates of PSL particles in Tests 1-1 to 1-4 were 13.0%, 14.8%, 15.4%, and 15.6%, respectively. Compared with the reference example, the removal rates of PSL particles were higher. [0043] From the point of view of the removal rate of the PSL particles in the reference example and the verification test 1-1, it can be said that the removal rate of the fine particles is improved by lengthening the supply time of the diluent. From the results of the verification tests 1-1 to 1-3, it can be said that when the inspection wafer W is rotated while the diluent is supplied, the number of rotations of the inspection wafer W is increased. To improve the removal rate of particles. In addition, since the removal rate of fine particles in the verification test 1-4 is higher than that in the verification test 1-1, it can be said that when the inspection wafer W is rotated and the diluent is supplied while the diluent is supplied, The method of flow improves the removal rate of particles. [Verification Test 2] The effect of moving the nozzle for supplying the diluent while rotating the inspection wafer W while supplying the diluent was verified. [Certification Test 2-1] The following example is referred to as the certification test 2-1. The diluent is supplied toward the center of the wafer W when the diluent is supplied while the inspection wafer W is rotated. 6 seconds. Secondly, it takes 6 seconds to move the nozzle that discharges the diluent from the position to the center of the wafer W to the position to the periphery of the wafer W. The diluent is supplied while the other is for reference. The example is also processed. [0045] For the verification test 2-1, the difference between the number of adhesion of the PSL particles before the test and the number of adhesion of the PSL particles after the test in the inspection wafer W was similarly calculated, and the removal rate of the PSL particles was calculated. FIG. 13 is a characteristic diagram showing the results and the removal rate of the PSL particles in the reference example and the verification test 2-1. In the verification test 2-1, the removal rate of PSL particles was 18.4%, which was higher than the reference example. Therefore, it can be said that when the inspection wafer W is rotated and the diluent is supplied, the removal rate of the particles is improved by moving the nozzle for supplying the diluent. [Verification Test 3] The effect of intermittently supplying the diluent while rotating the inspection wafer W while supplying the diluent was verified. [Certification Test 3-1] In the reference example, the following example is referred to as the certification test 3-1. The inspection wafer W is rotated while the diluent is supplied, and the number of revolutions is 1000 rpm. The inspection wafer W is rotated for 6 seconds, and the diluent is supplied for 6 seconds while facing the center of the wafer W. Next, the inspection wafer W is rotated by 1000 rpm for 6 seconds while the diluent is stopped. After removing the diluent on the surface of the inspection wafer W in seconds, the inspection wafer W was further rotated for 6 seconds at a rotation number of 1000 rpm, and the diluent was supplied toward the center of the wafer W for 6 seconds. [Verification Test 3-2] The following example is referred to as verification test 3-2: In addition to rotating the inspection wafer W while supplying diluent, the surface of the inspection wafer W is removed. In the case of the thinner, the number of rotations of the inspection wafer W is set to a number of rotations of 2000 rpm and the rotation is performed for 6 seconds, and the other processes are performed in the same manner as in the verification test 3-1. [Verification Test 3-3] The following example is referred to as Verification Test 3-3. In addition to rotating the inspection wafer W while supplying diluent, the surface of the inspection wafer W is removed. In the case of the thinner, the number of rotations of the inspection wafer W is set to a rotation number of 3000 rpm and the rotation is performed for 6 seconds, and the same processing as that of the verification test 3-1 is performed. [Certification Test 3-4] The following example is referred to as the certification test 3-4. In addition to rotating the inspection wafer W while supplying diluent, the surface of the inspection wafer W is removed. In the case of the thinner, the number of rotations of the inspection wafer W is set to a number of rotations of 3000 rpm and the rotation is performed for 2 seconds, and the same processing as in the verification test 3-1 is performed. [Certification Test 3-5] The following example is referred to as the certification test 3-5: In addition to rotating the inspection wafer W on one side and supplying diluent on the other, the dilution on the surface of the inspection wafer W is removed. In the case of a chemical agent, the number of rotations of the inspection wafer W is set to a number of rotations of 3000 rpm and the rotation is performed for 4 seconds. [0047] For the verification tests 3-1 to 3-5, the difference between the number of adhesion of the PSL particles before the test and the number of adhesion of the PSL particles after the test in the inspection wafer W is similarly calculated, and the number of PSL particles is calculated. Removal rate. FIG. 14 is a characteristic diagram showing the results and the removal rate of PSL particles in the reference examples and verification tests 3-1 to 3-3. 15 is a characteristic diagram showing removal rates of PSL particles in the verification tests 3-4, 3-5, the verification tests 3-3, and the reference examples. [0048] As shown in FIG. 14, in the verification tests 3-1 to 3-3, the removal rates of the PSL particles were 10.7%, 12.9%, and 53.7%, respectively. The inspection wafer W after the test was not dried in the verification tests 3-1 and 3-2, but was sufficiently dried in the verification test 3-3. Based on the results, it can be said that the surface of the wafer W can be dried when the number of rotations of the inspection wafer W is set to 3000 rpm when the diluent on the surface of the inspection wafer W is removed. When the diluent is supplied, particles on the surface of the wafer W can be efficiently removed. [0049] As shown in FIG. 15, in the verification tests 3-4 and 3-5, the removal rates of the PSL particles were 10.5% and 14.6%, respectively. Based on the results of 3-3 to 3-5, it can be said that when the thinner on the surface of the inspection wafer W is removed, the number of revolutions of the inspection wafer W is set to 3000 rpm and the number of revolutions is 4 For more than seconds, it is more effective to rotate the surface for more than 6 seconds to dry the surface of the wafer W. Then, when a diluent is supplied, particles on the surface of the wafer W can be efficiently removed. [0050] [Additional Test for Verification Test 3] It was also verified that after the inspection wafer W is rotated and the diluent is supplied, the supply of the diluent is stopped, and N ₂ gas is supplied, and thereafter, the dilution is supplied. Agent effect. [Certification Test 3-3a] In the Certification Test 3-3, the following example is referred to as the Certification Test 3-3a. When the thinner on the surface of the inspection wafer W is removed, the inspection wafer W is removed. The number of rotations is set to the number of rotations of 3000 rpm, and N ₂ gas is supplied to the inspection wafer W. [Certification Test 3-4a] In the Certification Test 3-4, the following example is set as the Certification Test 3-4a. When the thinner on the surface of the inspection wafer W is removed, the inspection wafer W is removed. The number of rotations is set to the number of rotations of 3000 rpm and the rotation is performed for 2 seconds, and N ₂ gas is supplied toward the inspection wafer W. [Certification Test 3-5a] In the Certification Test 3-5, the following example is set as the Certification Test 3-5a. When the thinner on the surface of the inspection wafer W is removed, the inspection wafer W is removed. The number of rotations is set to the number of rotations of 3000 rpm and the rotation is performed for 4 seconds, and N ₂ gas is supplied toward the inspection wafer W. [Certification Test 3-4b] The following example is referred to as the certification test 3-4b: Except that N ₂ gas is supplied to the surface of the inspection wafer W, the inspection wafer is rotated at 1000 rpm on one side. W is rotated, and the time for supplying the diluent toward the center of the wafer W is set to other than 3 seconds, and other processing is performed in the same manner as in the verification test 3-4a. For the verification tests 3-3a to 3-5a and verification tests 3-4b, the difference between the number of PSL particles before the test and the number of PSL particles after the test is also calculated and calculated. The removal rate of PSL particles is shown. 16 is a characteristic diagram showing the removal rate of PSL particles in verification tests 3-3a to 3-5a and the removal rate of PSL particles in verification tests 3-3a to 3-5a. 17 is a characteristic diagram showing the removal rate of the PSL particles in the verification test 3-4b and the removal rate of the PSL particles in the verification test 3-4a and the reference example. As shown in FIG. 16, the removal rates of the PSL particles in the verification tests 3-3a to 3-5a were 54.2%, 50.2%, and 53.8%, respectively, and the removal rates exceeded 50%. As shown in FIG. 17, in the verification test 3-4b, the removal rate of the PSL particles showed a value as high as 59.1%. In addition, in the additional test of the verification test 3 and the verification test 4 to be described later, the reference example is acquired again. As a result, the removal rate of the PSL particles in the reference example was 12.2%, which was approximately the same as the value obtained in the verification test 1, and the removal rate was unchanged. [0052] In the verification tests 3-4 and 3-5 in which the time intervals during which the diluent was discharged toward the inspection wafer W were set to 2 seconds and 4 seconds, respectively, the removal rates of the PSL particles were 12.2, respectively. %, 14.6%. Therefore, it can be said that when the diluent on the surface of the inspection wafer W is removed, the rotation number of the inspection wafer W is set to 3000 rpm, and the inspection wafer W is supplied to the inspection wafer W. The method of N ₂ gas can efficiently remove particles even in a short time. In addition, as shown in FIG. 17, in either of the verification test 3-4a and the verification test 3-4b, the removal rate of the PSL particles is also a high value. Therefore, it can be said that the wafer In the case of W drying, the method of blowing N ₂ gas to dry it, and then setting the time for supplying the diluent to a short time can also efficiently remove particles. [Verification Test 4] In addition, when the diluent was intermittently supplied to the inspection wafer W, the drying time and the wafer W when the diluent was repeatedly stopped to dry the wafer W were verified. The effect of supply of thinner and drying of wafer W. [Certification Test 4-1] In the certification test 3-4b, the following example is set as the certification test 4-1. When the thinner on the surface of the inspection wafer W is removed, one side faces the inspection crystal. The circle W is supplied with N ₂ gas, and the number of rotations of the inspection wafer W is set to the number of rotations of 3000 rpm, and the rotation is performed for 3 seconds. [Certificate Test 4-2] The following example is referred to as the Certify Test 4-2. In a state where the diluent is stopped following the processing of the certify test 4-1, the number of revolutions is set to 1000 rpm on one side. The inspection wafer W is rotated for 3 seconds, and while the N ₂ gas is supplied to remove the diluent on the surface of the inspection wafer W, the inspection wafer W is further rotated at a rotation speed of 1000 rpm, while the inspection wafer W faces the wafer W. The central portion was supplied with the diluent for 3 seconds. For the verification tests 4-1 to 4-2, the difference between the number of PSL particles before the test and the number of PSL particles after the test in the inspection wafer W was similarly calculated, and the removal rate of the PSL particles was calculated. [0054] FIG. 18 is a graph showing the results and characteristic diagrams of the removal rate of PSL particles in verification test 3-4b and the removal rate of PSL particles in verification test 4-1 and verification test 4-2 . In the verification test 3-4b, the removal rate of PSL particles is as high as 59.1%, but in the verification test 4-1, the removal rate of PSL particles is 67.2%, and in the verification test 4- In 2, the removal rate of PSL particles was 72.9%. [0055] Based on the results, it can be said that the inspection wafer W is rotated while the diluent is stopped, and the time for supplying the N ₂ gas is lengthened, so that the removal rate of the particles is improved, and more In a state where the diluent is stopped, the inspection wafer W is rotated while supplying the N ₂ gas while the inspection wafer W is rotated, and the diluent is supplied to the surface of the inspection wafer W while the inspection wafer W is rotated. The engineering method improves the removal rate of particles. [0056] As described above, in the case where the supply time of the diluent is lengthened, the rotation speed of the wafer W is increased, and the flow rate of the diluent is increased, the removal rate of the particles will be improved, in particular, It can be said that after the diluent is supplied and dried, fine particles can be efficiently removed by further supplying the diluent. In addition, when drying the wafer W, it is also possible to shorten the drying time and reduce the flow rate of the diluent by blowing gas onto the wafer W. In addition, by repeating the process of supplying the diluent to the wafer W several times and the process of drying the wafer W, particles can be efficiently removed. [0057] The SOC film was continuously formed on the inspection wafer W subjected to each of the reference example, verification test 3-4b, and verification test 4, and the number of plaques formed on the SOC film was counted. The number of plaques counted in each of the inspection wafers W of the reference example, verification test 3-4b, and verification test 4 were 214, 118, and 7, respectively. Compared with the reference example, the number of genital plaques was significantly reduced in the known verification test 3-4b, and in the verification test 4, the number was significantly reduced. [0058] Instead of the inspection wafer W, a wafer having a step pattern is formed, and each of the reference example, verification test 3-4b, and verification test 4 is performed thereon, and then a SOC film is formed and counted The number of plaques formed on the SOC film. The number of plaques counted in wafer W of the reference example, verification test 3-4b, and verification test 4 were 84, 20, and 4, respectively. From the results, it can be said that when the present invention is applied to a wafer W on which a step pattern is formed, particles can be similarly removed, and the formation of plaque in the coating film can be suppressed.

[0059]

2‧‧‧ cup body

3‧‧‧ coating liquid nozzle

4‧‧‧ thinner nozzle

5‧‧‧N ₂ gas nozzle

6‧‧‧ Nozzle unit

100‧‧‧ thinner

101‧‧‧ particles

102‧‧‧coating liquid

W‧‧‧ Wafer

[0011] [FIG. 1] A cross-sectional view of an SOC film coating apparatus according to an embodiment of the present invention. [Fig. 2] An explanatory diagram corresponding to the timing chart of the number of wafer rotations and the corresponding process. [Fig. 3] An explanatory diagram for explaining the effect of the embodiment of the present invention. [Fig. 4] An explanatory diagram for explaining the effect of the embodiment of the present invention. [FIG. 5] An explanatory diagram for explaining the effect of the embodiment of the present invention. [FIG. 6] An explanatory diagram for explaining the effect of the embodiment of the present invention. [FIG. 7] An explanatory diagram for explaining the effect of the embodiment of the present invention. [FIG. 8] An explanatory diagram for explaining the effect of the embodiment of the present invention. [FIG. 9] An explanatory diagram for explaining the effect of the embodiment of the present invention. [FIG. 10] An explanatory diagram for explaining the effect of the embodiment of the present invention. [FIG. 11] An explanatory diagram for explaining the effect of the embodiment of the present invention. [Fig. 12] A characteristic diagram showing the removal rate of PSL particles in the verification test 1. [Fig. [Fig. 13] A characteristic diagram showing the removal rate of PSL particles in the verification test 2. [Fig. [Fig. 14] A characteristic diagram showing the removal rate of PSL particles in the verification test 3. [Fig. [Fig. 15] A characteristic diagram showing the removal rate of PSL particles in the verification test 3. [Fig. [Fig. 16] A characteristic diagram showing the removal rate of PSL particles in the verification test 3. [Fig. [Fig. 17] A characteristic diagram showing the removal rate of PSL particles in the verification test 3. [Fig. [Fig. 18] A characteristic diagram showing the removal rate of PSL particles in the verification test 4. [Fig.

Claims (14)

A coating method comprising: (i) a process of holding a substrate horizontally; (ii) a process of wetting the entire surface of a substrate by a processing liquid; (ii) rotating the substrate about a vertical axis to make the surface of the substrate A process of drying; (ii) a process of supplying a cleaning solution to the surface of the substrate while rotating the substrate about a vertical axis; and a process of supplying a coating solution to the surface of the substrate to form a coating film. For example, the coating method according to the scope of application of the patent, wherein: the aforementioned cleaning solution is an organic solvent. For example, the coating method according to item 1 or 2 of the scope of patent application, wherein: The aforementioned treatment liquid is any of tetramethylammonium hydroxide or ammonia / hydrogen peroxide / water mixed liquid. For example, the coating method according to item 1 or 2 of the scope of patent application, wherein: The aforementioned treatment liquid and cleaning liquid are the same organic solvent. For example, the application method of the scope of patent application item 1 or 2, wherein: after the process of supplying the cleaning liquid to the surface of the substrate, perform: 的 the process of rotating the substrate around a vertical axis to dry the surface of the substrate; and The process of supplying the cleaning liquid to the surface of the substrate while rotating the substrate around the vertical axis. For example, the application method of the first or second patent application scope, wherein: (i) the process of rotating the substrate around the vertical axis to dry the surface of the substrate, the substrate is rotated around the vertical axis, and gas is emitted toward the substrate. For example, the application method of the first or second patent application scope, wherein: (1) the rotation direction of the substrate in the process of supplying the processing liquid to the substrate and the rotation direction of the substrate in the process of supplying the first cleaning liquid to the substrate; , Are opposite to each other. For example, the application method of the first or second patent application range, wherein: (1) the process of supplying the cleaning liquid to the aforementioned substrate is to supply the cleaning liquid for more than 3 seconds. For example, the application method of the first or second patent application range, wherein the supply time of the processing liquid in the process of wetting the entire surface of the substrate by the processing liquid is comparable to the supply of the cleaning liquid to the surface of the substrate The supply time of the cleaning liquid in the process is short. For example, the application method of the scope of patent application No. 1 or 2, in which: (1) the process of supplying the processing liquid to the substrate and the process of supplying the cleaning liquid to the substrate include a side so that the supply position of the cleaning liquid is from the center of the substrate A process in which a processing liquid and a cleaning liquid are supplied while moving toward the peripheral edge of the substrate. A memory medium stores a computer program used in a coating device. The coating device supplies a coating liquid to a substrate that is held horizontally and rotated about a vertical axis to perform coating. The memory medium has characteristics In order to implement the coating method according to any one of the scope of patent applications No. 1 to 10, a group of steps is incorporated. A coating device is characterized in that: a substrate holding portion for horizontally holding a substrate; a rotating mechanism for rotating the substrate holding portion about a vertical axis; a coating liquid nozzle for holding the substrate A coating liquid is supplied to the substrate of the substrate holding portion; a processing liquid nozzle supplies a processing liquid to the substrate held by the substrate holding portion; a cleaning liquid nozzle supplies a cleaning liquid to the substrate held by the substrate holding portion; and control In this step, the following steps are performed: a step of holding the substrate horizontally; a step of wetting the entire surface of the substrate with a processing liquid; and a step of rotating the substrate around a vertical axis to dry the surface of the substrate; Thereafter, a step of supplying the cleaning liquid to the surface of the substrate while rotating the substrate around the vertical axis, and a step of forming a coating film by supplying the coating liquid to the surface of the substrate. For example, the coating device according to item 12 of the application, wherein: the processing liquid and the cleaning liquid are the same solvent, and the processing liquid nozzle and the cleaning liquid nozzle are shared. For example, the coating device according to item 12 or 13 of the patent application scope includes: a gas supply nozzle to supply gas toward the substrate, the aforementioned control unit outputs a control signal so that, in the step of drying the surface of the substrate, The substrate rotates about a vertical axis, and one side emits gas toward the substrate.