JP2005045035A - Method of cleaning substrate, method of grinding and cleaning substrate, substrate cleaning device, and substrate grinding and cleaning system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning method which removes particles, chemicals, or the like left on a substrate after scrub cleaning a substrate with at least a part of its surface formed by a low-k material or a substrate with a part of its surface formed by a water-repellent material by chemicals. <P>SOLUTION: Rotating the substrate 2 with at least a part of its surface formed by the low-k material or the substrate 2 with a part of its surface formed by a water-repellent material at a rotational speed of not less than 600 min<SP>-1</SP>and supplying a cleaning water spread the cleaning water widely over the substrate 2 to be able to remove and clean the contaminant such as particles, chemicals or the like left on the substrate 2 after the scrub cleaning by chemicals. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a substrate cleaning method, a substrate polishing and cleaning method, a substrate cleaning apparatus, and a substrate polishing and cleaning system. In particular, the present invention relates to a method for cleaning a substrate in which at least a part of the surface is formed of a low-k material or a substrate in which at least a part of the surface is formed of a water-repellent material.

  In the manufacturing process of semiconductor devices, device layers are often formed on a semiconductor wafer. In order to accurately form several device layers, it is necessary to flatten and mirror the surface of the layer covering each device layer. Polishing is performed by a chemical mechanical polishing (hereinafter referred to as CMP) apparatus as a means for flattening and mirroring. The CMP apparatus has a turntable with a pad (polishing cloth) and a top ring, holds the substrate to be polished by the top ring, and rotates on a turntable while supplying slurry (abrasive liquid) to the sliding surface. The substrate to be polished is pressed against the pad with a constant pressure, and the surface of the substrate to be polished is polished flat and mirror-like. After such polishing, particles such as slurry and polishing debris remain on the substrate. Therefore, cleaning is performed by scrubbing with a sponge or the like while applying a chemical solution after polishing, and further, pure water (hereinafter referred to as DIW) or the like. It was washed away with a cleaning solution.

  In recent years, with the progress of high integration of semiconductor devices, the dimensions of integrated devices are becoming finer and the distance between wirings is becoming narrower. Therefore, if particles larger than the distance between the wirings are present on the substrate, problems such as short-circuiting of the wiring occur. Therefore, in the processing of the substrate, it is important to make the surface flat and mirror-finished and clean. In view of this, a polishing apparatus has been proposed that provides a substrate with high working efficiency and high cleanliness (see Patent Document 1).

JP 2001-35821 A

  In order to solve the problem of wiring delay (RC delay) caused by miniaturization of wiring for further high integration of semiconductor devices and narrowing of the distance between wirings, a low-k ( Lokei) (low dielectric constant) materials are being used. The low-k material has a water-repellent surface unlike a conventional substrate material. When a material having a surface having water repellency, such as a low-k material, is used, even if an attempt is made to wash away with cleaning water, the surface has water repellency. May flow out toward the outer periphery of the substrate, and may not reach the entire surface of the substrate and may remain unwashed. Therefore, the present invention relates to a method for cleaning a substrate for cleaning the entire surface of a substrate formed of a material having water repellency, represented by a low-k (low dielectric constant) material, with a cleaning water, and polishing the substrate. And a cleaning method, a substrate cleaning apparatus, and a substrate polishing and cleaning system.

In order to achieve the above object, the substrate cleaning method according to the first aspect of the present invention includes, as shown in FIG. 1, for example, a substrate 2 in which at least a part of the surface is formed of a low-k material. After the primary cleaning step ST2 for scrub cleaning with a chemical solution in the cleaning machine 20, and after the primary cleaning process ST2, the secondary cleaning machine 30 different from the primary cleaning machine 20 is rotated at a rotational speed of 600 min ⁻¹ or more for a predetermined time. A secondary cleaning step ST3 for supplying cleaning water to the substrate 2 and cleaning the substrate 2;

With this configuration, after scrub cleaning with a chemical solution, even if dirt such as particles or chemical solution remains on a substrate on which at least a part of the surface is formed of a low-k material, the rotation is 600 min ⁻¹ or more. Since the cleaning water is supplied to the substrate rotated at a speed to perform cleaning, the cleaning water spreads over the entire surface of the substrate, and particles and chemicals on the entire surface of the substrate can be washed away.

In order to achieve the above object, a substrate cleaning method according to a second aspect of the present invention is directed to a substrate 2 in which at least a part of the surface is formed of a water-repellent material as shown in FIG. After the primary cleaning step ST2 for scrub cleaning with a chemical solution in the cleaning machine 20, and after the primary cleaning process ST2, the secondary cleaning machine 30 different from the primary cleaning machine 20 is rotated at a rotational speed of 600 min ⁻¹ or more for a predetermined time. A secondary cleaning step ST3 for supplying cleaning water to the substrate 2 and cleaning the substrate 2;

With this configuration, after scrub cleaning with a chemical solution, even if dirt such as particles or chemical solution remains on a substrate on which at least a part of the surface is formed of a water-repellent material, the rotation is 600 min ⁻¹ or more. Since the cleaning water is supplied to the substrate rotated at a speed to perform cleaning, the cleaning water spreads over the entire surface of the substrate, and particles and chemicals on the entire surface of the substrate can be washed away.

  Moreover, the substrate cleaning method according to the invention described in claim 3 is, for example, as shown in FIG. 1, in the substrate 2 cleaning method according to claim 1 or 2, after the secondary cleaning step ST <b> 3, After the pre-drying step ST4 for reducing the rotation speed of the substrate 2 and the pre-drying step ST4, the drying step ST5 for accelerating and rotating the substrate 2 without supplying cleaning water and removing the cleaning water on the substrate 2 Is provided.

  With this configuration, after the secondary cleaning, the rotation speed of the substrate is reduced, and then the rotation speed is accelerated and rotated at a high speed, so that the substrate can be dried in a short time. Therefore, it is possible to obtain a clean and dry substrate without leaving a watermark or the like.

In addition, the substrate cleaning method according to the invention described in claim 4 is the secondary cleaning method according to any one of claims 1 to 3, for example, as shown in FIG. The rotation speed of the substrate 2 in the cleaning step ST3 is 600 min ⁻¹ or more and 1,400 min ⁻¹ or less.

With this configuration, since the rotation speed of the substrate in the secondary cleaning process is 600 min ⁻¹ or more and 1,400 min ⁻¹ or less, the cleaning water spreads over the entire surface of the substrate, washing away dirt such as particles and chemicals on the entire surface of the substrate. In addition, the rotation speed is equal to or lower than the rotation speed at which the mist containing the chemical solution or the entrainment of liquid droplets caused by the airflow generated due to the high-speed rotation of the substrate occurs.

  In order to achieve the above object, a method for polishing and cleaning a substrate according to a fifth aspect of the present invention includes, for example, as illustrated in FIG. 1, the substrate according to any one of the first to fourth aspects. Substrate 2 cleaning steps ST2 to ST5 by a cleaning method and chemical mechanical polishing step ST1 are provided.

  If comprised in this way, since the board | substrate which carried out the chemical mechanical polishing, and was planarized and mirror-polished is wash | cleaned by the washing | cleaning method of the board | substrate of any one of Claim 1 thru | or 4, At least one part of the surface Even if the substrate is made of a low-k material or at least part of the surface is made of a water-repellent material, it is flattened and mirror-finished by chemical mechanical polishing, and has a higher degree of cleanliness. A substrate is provided.

In order to achieve the above object, a substrate cleaning apparatus according to a sixth aspect of the present invention includes a first rotating unit 24 that holds and rotates the substrate 2 as shown in FIG. 4 (see FIG. 2). And the first cleaning machine 20 having the first nozzles 25 and 27 (see FIG. 2) for spraying the chemical liquid onto the rotating substrate 2 held by the first rotating unit 24 and holding and rotating the substrate 2. The second rotating units 31 and 32 (see FIG. 3), which are different from the first rotating unit 24, and the second rotating unit 31 and 32 are used to supply cleaning water to the rotating substrate 2 that is rotating. Secondary cleaning machine 30 having two nozzles 34 (see FIG. 3), transporters 43 and 44 for transporting the substrate 2 held by the primary cleaning machine 20 to the secondary cleaning machine 30, and the primary cleaning machine 20. The substrate 2 cleaned in step 1 is transferred to the secondary cleaning machine 30 by the transfer machines 43 and 44, and is transferred to the secondary cleaning machine 30. There are, and a control unit 60 for controlling so that a predetermined time, washed by supplying washing water is rotated at 600 min ^-1 or more rotational speed.

With this configuration, the substrate is rotated and cleaned by the first rotating unit while spraying the chemical solution from the first nozzle in the primary cleaning machine, and the substrate is transferred from the primary cleaning machine to the secondary cleaning machine by the transfer machine. In addition, since the substrate is rotated at a rotation speed of 600 min ⁻¹ or more for a predetermined time in the second rotating unit while supplying cleaning water with the secondary cleaning machine, the substrate is cleaned with the chemical solution by the first cleaning machine. The entire surface of the substrate can be washed away with cleaning water by a secondary cleaning machine. Therefore, even if the substrate is formed of at least a part of the surface with a water-repellent material or the substrate is formed of at least a part of the surface with a water-repellent material, particles, chemicals, etc. It becomes a substrate cleaning apparatus which can wash away dirt.

  Further, the substrate cleaning apparatus according to the invention described in claim 7 is the substrate cleaning apparatus according to claim 6, as shown in FIG. 4, for example. After the cleaning, the rotation speed of the substrate 2 is decreased, and thereafter, the substrate 2 is controlled to be accelerated and rotated at a high speed without supplying cleaning water.

  With such a configuration, after the secondary cleaning, the rotation speed of the substrate is reduced, and then the rotation speed is accelerated and rotated at a high speed, so that the substrate can be dried in a short time. Therefore, it is possible to obtain a clean and dry substrate without leaving a watermark or the like.

Further, the substrate cleaning apparatus according to the invention described in claim 8 is the substrate cleaning apparatus according to claim 6 or 7, in which, for example, as shown in FIG. Then, the substrate is controlled to be cleaned by rotating at a rotation speed of 600 min ⁻¹ or more and 1,400 min ⁻¹ or less.

With this configuration, since the rotation speed of the substrate in the secondary cleaning step is 600 min ⁻¹ or more and 1,400 min ⁻¹ or less, the cleaning water spreads over the entire surface of the substrate and is generated due to the high speed rotation of the substrate. Entrainment of mist and droplets containing chemicals due to airflow is unlikely to occur.

  Furthermore, in order to achieve the above object, a substrate polishing and cleaning system according to a ninth aspect of the present invention is the substrate according to any one of the sixth to eighth aspects as shown in FIG. The cleaning apparatuses 20, 30, 43, 44, and 60 and the substrate polishing apparatus 10 that chemically and mechanically polishes the substrate 2 using slurry are provided.

  With this configuration, the substrate mechanically polished by the substrate polishing apparatus can be washed away with the cleaning water by the substrate cleaning apparatus, so that at least a part of the surface is formed of a low-k material. Even if the surface of the substrate is made of a water-repellent material, the substrate surface is polished to a flat and mirror-like surface, and then the substrate polishing is performed to wash away particles and chemicals on the entire surface of the substrate. And a cleaning system.

After primary cleaning in which at least a part of the surface is formed of a low-k material or a substrate in which at least a part of the surface is formed of a water-repellent material is scrubbed with a chemical solution, at a rotation speed of 600 min ⁻¹ or more. When cleaning water is supplied to the substrate while rotating, the cleaning water spreads over the entire surface of the substrate, so that secondary cleaning for removing dirt such as particles and chemicals remaining on the substrate can be performed. Further, by performing the primary cleaning and the secondary cleaning with separate cleaning machines, it is possible to prevent back-contamination due to mist containing a chemical solution for the primary cleaning in the secondary cleaning.

  Embodiments of the present invention will be described below with reference to the drawings. In each figure, the same or equivalent devices are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a schematic view showing a work procedure of a substrate polishing and cleaning method according to the present invention. The substrate polishing apparatus 10 includes a top ring 12 that holds a substrate and a slurry nozzle 13 that supplies slurry on a circular turntable 11. A pad is affixed on the turntable 11. The top ring 12 holds the substrate 2 so as to cover the non-polished surface and the side surface of the substrate 2, and presses the vertical lower surface, which is the polished surface, against the rotating pad with a predetermined pressure to polish the substrate 2. From the slurry nozzle 13, slurry is supplied onto the pad. The substrate 2 is held on the top ring 12 with the surface in which the electric circuit is incorporated facing vertically downward, and is polished (CMP) to a flat and mirror surface by the slurry on the pad of the turntable 11 (step ST1).

  The substrate 2 polished by the substrate polishing apparatus 10 and adhering particles such as slurry and polishing scraps is conveyed to the primary cleaning machine 20. In the primary cleaning machine 20, primary cleaning is performed to remove particles on the substrate 2 by scrubbing the substrate 2 while spraying a chemical solution (step ST2).

Here, with reference to the block diagram of FIG. 2, the primary washing machine 20 is demonstrated in detail. FIG. 2A shows a portion that holds and rotates the substrate 2. That is, six rollers 24 are arranged so as to surround the periphery of the substrate. Each roller 24 has a cylindrical shape and includes a convex portion 24a at the center of the upper surface thereof. The substrate 2 is held by the upper surface of the roller 24 with the edge thereof being pressed horizontally by the convex portion 24 a on the upper surface of the roller 24. When the roller 24 rotates around the central axis, the edge thereof is rotated by the convex portion 24 a, so that the substrate 2 rotates as the roller 24 rotates. Note that the number of rollers 24 is not limited to six, but may be configured to support and rotate the substrate 2. The rotation speed of the substrate 2 is often a low rotation speed of about 100 min ⁻¹ , but may be other rotation speeds.

  FIG. 2B schematically shows a configuration for cleaning the substrate 2. The substrate 2 is carried and rotated by the roller 24 with the mirror surface side 2a in which an electric circuit (not shown) is incorporated facing vertically upward. As the substrate 2 is sandwiched, the back surface cleaning member 21 is disposed so as to contact the back surface side 2b of the substrate so that the mirror surface cleaning member 22 contacts the mirror surface side 2a of the substrate. The mirror surface cleaning member 22 and the back surface cleaning member 21 are configured to be movable up and down so as to be separated from and in contact with the surfaces 2 a and 2 b of the substrate 2 so as not to obstruct the replacement of the substrate 2. A mirror surface chemical nozzle 27 for spraying a chemical liquid from above toward the mirror surface side 2 a of the substrate 2, a mirror surface pure water nozzle 28 for supplying DIW, and a back surface chemical liquid nozzle for spraying a chemical liquid from below toward the back surface side 2 b of the substrate 2. The back surface pure water nozzle 26 which supplies 25 and DIW is arrange | positioned.

The chemical solution used in the primary cleaning machine 20 varies depending on the slurry used in CMP, but the optimal chemical solution is sprayed from the mirror surface chemical solution nozzle 27 and the back surface chemical solution nozzle 25 onto the mirror surface side 2a and the back surface side 2b of the substrate 2. The mirror surface cleaning member 22 and the back surface cleaning member 21 are in contact with the substrate 2 on which the chemical solution is sprinkled while rotating so as to rub the entire surface. The mirror surface cleaning member 22 is formed of PVA (polyvinyl alcohol) sponge or the like in a cylindrical shape, and the back surface cleaning member 21 is formed of PVA sponge, nonwoven fabric or the like in a cylindrical shape, and changes the contact surface with the substrate 2 respectively. Therefore, it rotates around the axis at 100 to 150 min ⁻¹ . However, the rotational speed of the mirror surface cleaning member 22 and the back surface cleaning member 21 is not limited to the above. The surface particles activated by the chemical solution are scrubbed when the mirror surface cleaning member 22 and the back surface cleaning member 21 rub the surface of the substrate 2 to clean the surface of the substrate. After scrubbing with a chemical solution, DIW may be further washed with DIW while supplying DIW from the mirror surface pure water nozzle 28 and the back surface pure water nozzle 26.

Returning to FIG. 1, the description of the work procedure of the substrate polishing and cleaning method will be continued. The substrate 2 that has undergone the primary cleaning is transported to the secondary cleaning machine 30. The chemical solution and particles used in the primary cleaning remain on the surface of the substrate 2, and the secondary cleaning machine 30 supplies DIW as cleaning water to wash away the remaining chemical solution and particles. Next cleaning is performed (step ST3). The cleaning water may be DIW, or highly functional water such as ion water, ozone (O ₃ ) water, hydrogen water, or the like.

  Here, with reference to the perspective view of FIG. 3, the secondary washing machine 30 is demonstrated in detail. In the secondary cleaning machine 30, a plurality of arms 31 are installed on the rotary table 32 at equal intervals. The substrate 2 is rotated by holding the substrate 2 with the arm 31 and rotating the rotary table 32. DIW is supplied to the vicinity of the center of the rotating substrate 2 from the cleaning water nozzle 34 in order to spread DIW over the entire substrate surface. In FIG. 3, only the cleaning water nozzle 34 for supplying DIW from the upper side is shown, but the lower side is similarly provided with a cleaning water nozzle 34 (not shown) to supply DIW onto the substrate 2. The upper surface (mirror surface) 2a and the lower surface (back surface) 2b are simultaneously cleaned.

The rotation speed of the substrate 2 is set to a high speed rotation of 600 min ⁻¹ or more. The rotation speed is preferably 600 min ⁻¹ or more and 1,400 min ⁻¹ or less, more preferably 800 min ⁻¹ or more and 1,200 min ⁻¹ or less, and most preferably 900 min ⁻¹ or more and 1,100 min ⁻¹ or less. ^-1 or less. With such high-speed rotation, even if the substrate 2 is at least part of the surface formed of a low-k material or at least part of the surface is formed of a water-repellent material, The DIW supplied from the cleaning water nozzle 34 onto the substrate 2 forms a narrow channel and does not flow out toward the outer periphery of the substrate 2, and the cleaning water spreads over the entire surface of the substrate 2. For this reason, the portion that has not been washed off remains on the substrate 2 and the cleanliness of the entire surface of the substrate 2 is increased. The low-k material here refers to a material having a relative dielectric constant k of about 3 or less, and the substrate 2 in which at least a part of the surface is formed of the low-k material is a low-k material. It does not need to be formed, and includes a substrate 2 on which a low-k film is formed on a surface on which an electric circuit is incorporated. Further, the water repellency means that the contact angle according to JIS R 3257 is 70 ° or more, and the substrate 2 in which at least a part of the surface is formed of a water repellant material is formed entirely of the water repellant material. The substrate 2 includes a substrate 2 on which a film of a water-repellent material is formed on a surface on which an electric circuit is incorporated.

For a general substrate having a substrate diameter of 300 mm, if the substrate is rotated at a high speed of about 1,500 min ⁻¹ or more, a mist or liquid containing a chemical solution in the cleaning machine chamber is generated by an air flow in the cleaning machine chamber generated by the rotation of the substrate or the like. The possibility of back-contamination by entraining drops increases. Therefore, the reverse contamination can be prevented from occurring by not rotating at a high speed exceeding 1,400 min ⁻¹ . However, in the case of a substrate having a substrate diameter of 200 mm, the above-mentioned counter-contamination may occur at a rotational speed of about 2,000 min ⁻¹ or more. Therefore, the rotational speed of the substrate may be increased to about 2,000 min ⁻¹ .

  Further, since the primary cleaning process (step ST2) and the secondary cleaning process (step ST3) are performed by the separate primary cleaning machine 20 and secondary cleaning machine 30, the primary cleaning machine 20 and the secondary cleaning process are performed as described later. By storing the cleaning machine 30 in a room partitioned by a partition wall (see FIG. 4), the secondary cleaning process (step ST3) from the mist and droplets containing the chemical solution generated in the primary cleaning process (step ST2). No back-contamination occurs.

  It should be noted that the predetermined time required for the secondary cleaning step may be a time sufficient for DIW to reach the entire surface of the rotating substrate 2, and may be 10 seconds or more as described later in the description of the embodiment. , Preferably 20 seconds or longer.

Returning to FIG. 1, the description of the work procedure of the polishing and cleaning method for the substrate 2 will be continued. When the secondary cleaning is completed, a pre-drying process for lowering the rotational speed of rotating the substrate 2 in the secondary cleaning machine 30 to a low rotational speed is performed (step ST4). This makes the difference in rotational speed from the high speed rotation in the subsequent drying process (step ST5) noticeable, and the DIW on the substrate 2 is removed earlier in the acceleration stage of the rotational speed in the drying process (step ST5). Process. The rotational speed to the well to a 500 min ^-1 or less, more preferably, to 200 min ^-1 or less. Note that it is preferable to continue supplying DIW onto the substrate 2 also in the pre-drying step (step ST4). This is because when the supply of DIW is stopped, the surface of the substrate 2 is in a dry state and a watermark or the like may be formed.

When the rotation speed of the substrate 2 becomes low in the pre-drying process (step ST4), the supply of DIW from the cleaning water nozzle 34 onto the substrate 2 is stopped, and the rotation speed of the substrate 2 is rapidly rotated at a high speed of 1,500 min ⁻¹ or more. Accelerate to. Due to the acceleration of the rotational speed, the water droplets of DIW on the surface of the substrate 2 are blown off in a short time. Then, the substrate 2 can be completely dried by rotating at a high rotation speed for about 30 seconds (step ST5). A high rotation speed is preferable, but if it is too high, the substrate 2 may be damaged, and if it is damaged, it is dangerous because fragments are scattered at a high speed. Therefore, the rotation speed is preferably about 3,000 min ⁻¹ or less. In the drying process (step ST5), drying may be performed while supplying a clean inert gas to the substrate 2 in order to accelerate drying and prevent back-contamination due to mist or the like. In addition, in the drying process (step ST5), since supply of DIW is stopped, in general, back contamination due to mist or the like does not occur.

  Next, a substrate polishing apparatus and a substrate polishing and cleaning system according to the present invention will be described with reference to the schematic diagram of FIG. FIG. 4 is a schematic diagram showing a substrate polishing and cleaning system having two series of the substrate polishing apparatus 10, the primary cleaning machine 20, and the secondary cleaning machine 30. The substrate polishing apparatus 10, the primary cleaning machine 20, and the secondary cleaning machine 30 are each installed in a room partitioned by a partition, and each room is independently evacuated so that the atmosphere does not interfere with each other. It has become. Therefore, the mist containing the slurry in the substrate polishing apparatus 10 does not adversely affect the primary cleaning machine 20 and the secondary cleaning machine 30, and the mist containing the chemical solution in the primary cleaning machine 20 is secondary cleaned. The machine 30 is not adversely affected. A delivery table 41 for temporarily placing the substrate 2 is also installed in the room of each substrate cleaning apparatus 10. A room for the primary cleaning machine 20 is disposed adjacent to the room for the substrate cleaning apparatus 10. A transporter 43 that transports the substrate 2 is installed between the rooms of the two primary cleaning machines 20. Next to the room of the primary cleaning machine 20, a reversing machine 42 that reverses the front and back of the substrate 2 is installed for each series, and the room of the secondary cleaning machine 30 is arranged beyond that. Between the chambers of the two secondary cleaning machines 30, a transporter 44 that transports the substrate 2 is installed. A loading / unloading unit 50 is installed adjacent to the room of the secondary cleaning machine 30 and the transfer unit 44 to install a cassette for storing a plurality of substrates 2 that are to be polished / cleaned or have been polished / cleaned. Is arranged.

The substrate 2 taken out from the load / unload unit 50 and having the electric circuit incorporated therein by the reversing machine 42 is directed downward, and is transferred to the substrate polishing apparatus 10. The substrate 2 is polished (CMP) using the slurry by the substrate polishing apparatus 10, and the surface on which the electric circuit is incorporated is flattened and mirror-finished. The polished substrate 2 is transferred to the primary cleaning machine 20 by the transfer machine 43 through the delivery table 41, and the front and back sides are reversed by the reversing machine 42 (the mirror side is turned upward). The primary cleaning machine 20 scrubs the surface of the substrate 2 with the front surface cleaning member 22 and the back surface cleaning member 21 (see FIG. 1) while spraying the chemical solution. The scrubbed substrate 2 is transferred to the secondary cleaning machine 30 by the transfer machine 43 or the transfer machine 44. In the secondary cleaning machine 30, first, dirt such as particles and chemicals on the substrate 2 is removed by secondary cleaning that supplies DIW as cleaning water while rotating the substrate 2 at a high speed of 600 min ⁻¹ or more. Subsequently, after the rotational speed is lowered to 500 min ⁻¹ or less, the supply of DIW is stopped, and the substrate 2 is dried by accelerating and rotating the rotational speed at a high speed of 1,500 min ⁻¹ or more at a stretch. The dried substrate 2 is returned to the load / unload unit 50 by the transporter 44. In the substrate polishing and cleaning system shown in FIG. 4, since the substrate polishing apparatus 10, the primary cleaning machine 20, and the secondary cleaning machine 30 are provided in two lines, operations from polishing to cleaning / drying can be performed in parallel.

  The above operation is controlled by the control device 60. In FIG. 4, only main communication paths are illustrated, but each device of the substrate polishing and cleaning system is connected to the control device 60 and operates according to a signal from the control device 60. The control device 60 stores a program for each operation. For example, the rotation speed and the cleaning time at the time of transporting the substrate 2 by the transporters 43 and 44, and the secondary cleaning by the secondary cleaning machine 30 are decreased in the pre-drying stage. Rotation speed and high rotation speed when drying are also incorporated. Since the operation program is incorporated in the control device, the above-described polishing, cleaning and drying operations can be easily realized.

  The substrate cleaning apparatus is obtained by removing the substrate polishing apparatus 10, the delivery table 41 and the reversing machine 42 from the substrate polishing and cleaning system shown in FIG. 4, and the substrate 2 is directly removed from the load / unload unit 50. Except for being carried to 20, the configuration is the same as that of the substrate polishing and cleaning system described above.

  As described above, according to the substrate cleaning method, the substrate polishing and cleaning method, the substrate cleaning apparatus, and the substrate polishing and cleaning system according to the present invention, an extra DIW is supplied without providing a special apparatus. Therefore, it is possible to provide a clean substrate regardless of whether the surface is a substrate formed of a low-k material or a substrate formed of a water-repellent material. it can. It can also be realized by changing a necessary operation method or incorporating the operation method into the control device.

  Hereinafter, the substrate cleaning method according to the present invention will be described in more detail with reference to Examples and Comparative Examples. In this example, a substrate in which a surface on which an electric circuit is incorporated is formed of a low-k material film is used. After the substrate is polished (CMP) using slurry, primary cleaning and secondary cleaning are performed as described below. As an example and a comparative example, on the film (mirror surface) of the low-k material after the secondary cleaning. The dirt was observed.

In the examples, scrubbing with a roll sponge while spraying the acid-based chemical solution for cleaning the Low-k material, and after performing the primary cleaning, 0.5 L / min is applied to the substrate rotating at a rotation speed of 1,000 min ⁻¹ . DIW was supplied to perform secondary cleaning for 20 seconds. On the other hand, as Reference Example 1, scrubbing with a roll sponge while spraying a low-k material cleaning acid chemical solution, and after performing primary cleaning, a substrate rotating at a rotational speed of 1,000 min ⁻¹ was added to the substrate. Secondary cleaning was performed for 5 seconds by supplying DIL at 5 L / min. In this reference example 1, the rotation speed of the substrate in the secondary cleaning is the same as that in the example, but the cleaning in which the time of the secondary cleaning does not satisfy the predetermined time is performed. Further, in Reference Example 2, scrubbing with a roll sponge while spraying DIW and performing primary cleaning, then supplying 0.5 L / min DIW to a substrate rotating at a rotation speed of 100 min ⁻¹ for 5 seconds. Secondary cleaning was performed. Furthermore, in Reference Example 3, scrubbing with a roll sponge while spraying a low-k material cleaning acid chemical solution, and after performing primary cleaning, 0.5 L / min is applied to the substrate rotating at a rotation speed of 100 min ^−1. DIW was supplied to perform secondary cleaning for 5 seconds. In Reference Example 2 and Reference Example 3, the substrate was cleaned by a conventional cleaning method.

  FIG. 5 shows the state of contamination on the low-k material film (mirror surface) after the secondary cleaning. 5A shows an example, FIG. 5B shows the reference example 1, FIG. 5C shows the reference example 2, and FIG. 5D shows the state of the stain on the mirror surface of the reference example 3. FIG. As is apparent from FIG. 5, the contamination of the example is extremely less than that of other cleaning methods. Furthermore, when the number of stains on the mirror surface of each substrate was counted, the ratio of the numbers was as follows: Example: Reference Example 1: Reference Example 2: Reference Example 3: 1: 2.5: 11.5: 4. 4. Thus, in the embodiment according to the present invention, the cleanliness of the substrate surface can be remarkably increased.

Under the same conditions as in the above example, only the rotation speed of the substrate was changed and the degree of DIW reaching the entire surface of the substrate was observed. As a result, the rotation speed of 100 min ⁻¹ was not sufficient as in Reference Example 3 above. However, it was observed that the rotation speed was almost 600 min ⁻¹ .

  In addition, when only the secondary cleaning time was changed under the same conditions as in the above example and the degree of DIW reaching the entire surface of the substrate was observed, 5 seconds was not sufficient as in Reference Example 1 above. In 10 seconds, it was observed that it was almost complete.

It is a schematic diagram which shows the operation | movement procedure of the grinding | polishing and washing | cleaning method of the board | substrate which concerns on this invention. It is a block diagram explaining a primary washing machine. FIG. 2A shows a portion that holds and rotates the substrate. FIG. 2B schematically shows a configuration for cleaning the substrate. It is a perspective view explaining a secondary washing machine. It is a schematic diagram explaining the substrate polishing and cleaning system according to the present invention. It is an observation result which shows the mode of the stain | pollution | contamination of the substrate surface after secondary cleaning.

Explanation of symbols

2 Substrate 10 Substrate polishing device 20 Primary cleaning machine 21 Back surface cleaning member 22 Mirror surface cleaning member 24 Roller 30 Secondary cleaning machine 31 Arm 32 Rotating table 34 Washing water nozzle 41 Transfer table 42 Reversing machine 43, 44 Transporter 50 Load / Unload Part

Claims (9)

A primary cleaning step of scrubbing a substrate having a surface formed of a low-k material with a chemical in a primary cleaning machine;
After the primary cleaning step, in a secondary cleaning machine different from the primary cleaning machine, cleaning water is supplied to the substrate rotated at a rotation speed of 600 min ⁻¹ or more for a predetermined time to clean the substrate. A secondary cleaning step to perform;
Substrate cleaning method. A primary cleaning step of scrubbing a substrate having a surface formed of a water-repellent material with a chemical in a primary cleaning machine;
After the primary cleaning step, in a secondary cleaning machine different from the primary cleaning machine, cleaning water is supplied to the substrate rotated at a rotation speed of 600 min ⁻¹ or more for a predetermined time to clean the substrate. A secondary cleaning step to perform;
Substrate cleaning method. A pre-drying step of reducing the rotation speed of the substrate after the secondary cleaning step;
After the pre-drying step, the method includes a drying step of removing the cleaning water on the substrate by accelerating and rotating the substrate at a high speed without supplying cleaning water;
The method for cleaning a substrate according to claim 1 or 2. The rotation speed of the substrate in the second cleaning step is 600 min ⁻¹ or more and 1,400 min ⁻¹ or less;
The method for cleaning a substrate according to any one of claims 1 to 3. A step of cleaning the substrate by the method for cleaning a substrate according to any one of claims 1 to 4;
And chemical mechanical polishing the substrate;
A method for polishing and cleaning a substrate. A primary cleaning machine having a first rotating part for holding and rotating a substrate, and a first nozzle for spraying a chemical on the substrate held and rotating by the first rotating part;
A second rotating unit different from the first rotating unit that holds and rotates the substrate, and a second nozzle that supplies cleaning water to the rotating substrate held and rotated by the second rotating unit. A secondary washer having:
A transporter for transporting the substrate held by the primary cleaning machine to the secondary cleaning machine;
The substrate cleaned by the primary cleaning machine is transferred to the secondary cleaning machine by the transfer machine, and the secondary cleaning machine is rotated at a rotational speed of 600 min ⁻¹ or more for a predetermined time to supply cleaning water. And a control device that performs control so as to perform cleaning.
Substrate cleaning device. The control device controls the secondary cleaning machine to reduce the rotation speed of the substrate after the second cleaning, and then to accelerate and rotate the substrate without supplying cleaning water. I do;
The substrate cleaning apparatus according to claim 6. The control device performs control so that the rotation speed of the secondary cleaning machine is 600 min ⁻¹ or more and 1,400 min ⁻¹ or less;
The substrate cleaning apparatus according to claim 6 or 7. A substrate cleaning apparatus according to any one of claims 6 to 8;
A substrate polishing apparatus for chemically and mechanically polishing the substrate using a slurry;
Substrate polishing and cleaning system.

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