Substrate processing apparatus

Abstract

The substrate processing apparatus 1 is provided with an indexer robot that causes the substrate W to enter and exit with respect to a carrier, a polishing unit 22 that polishes the back surface of the substrate W while heating the substrate W, and a substrate transfer robot that transfers the substrate W transferred from the indexer robot to the polishing unit. The polishing unit 22 is provided with a holding rotation section 35 that rotates the substrate W while holding the substrate W in a horizontal attitude, a heat plate 45 that heats the substrate W, and a polishing tool 96 that polishes the back surface of the substrate W by chemical mechanical grinding while being in contact with the back surface of the substrate W that is rotated while being heated.

Description

Technical Field

[0001] This invention relates to a substrate processing apparatus for grinding the back side of a substrate. Examples of substrates include semiconductor substrates, substrates for FPDs (Flat Panel Displays), glass substrates for photomasks, substrates for optical discs, substrates for magnetic disks, ceramic substrates, and substrates for solar cells. Examples of FPDs include liquid crystal display devices and organic EL (electroluminescence) display devices. Here, the back side of the substrate refers to the side of the substrate from which electronic circuitry is not formed, relative to the surface of the substrate that is the side where electronic circuitry is formed (device surface). Background Technology

[0002] A polishing apparatus for polishing the back side of a substrate includes a polishing head and a holding and rotating unit. The polishing apparatus supplies polishing fluid, thereby bringing the polishing head into contact with the back side of the substrate to polish the substrate (see, for example, Patent Document 1). It should be noted that the holding and rotating unit rotates the substrate while holding it in a horizontal position.

[0003] In addition, as other polishing apparatuses, there are known polishing apparatuses that perform dry chemical-mechanical grinding (CMG) on substrates (see, for example, Patent Document 2). This polishing apparatus includes synthetic abrasive stones and a rotating holding unit. The synthetic abrasive stones are formed by fixing abrasive particles (grits) with a resin binder. This polishing apparatus polishes the substrate by bringing the synthetic abrasive stones into contact with the substrate. Furthermore, there are substrate processing apparatuses with polishing tools for removing contaminants and contact marks from the back side of the substrate (see, for example, Patent Document 3).

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent No. 6162417

[0007] Patent Document 2: Japanese Patent No. 6779540

[0008] Patent Document 3: Japanese Patent No. 6740065 Summary of the Invention

[0009] The problem that the invention aims to solve

[0010] However, existing devices with the above-described configuration have the following problems. Specifically, in recent years, there has been a problem of defocusing (so-called out-of-focusing) in EUV (Extreme Ultraviolet) exposure machines caused by the flatness of the substrate (e.g., the back of a wafer). One cause of poor flatness is considered to be scratches. Therefore, in order to remove scratches, the use of a synthetic abrasive stone as a polishing tool, as described in Patent Document 2, has been investigated. Here, since the polishing process is time-consuming, it is desirable to shorten the polishing time.

[0011] The present invention was made in view of the above-mentioned circumstances, and its object is to provide a substrate processing apparatus that can shorten the time of polishing process.

[0012] Problem-solving methods

[0013] To achieve the above objectives, the present invention employs the following configuration. Specifically, the substrate processing apparatus of the present invention includes: a sorting robot that moves a substrate in and out relative to a carrier; a grinding unit that grinds the back side of the substrate while heating it; and a substrate conveying robot that conveys the substrate from the sorting robot to the grinding unit. The grinding unit includes: a rotating holding unit that rotates the substrate while holding it in a horizontal position; a heating mechanism that heats the substrate; and a grinding tool that contacts the back side of the heated and rotating substrate and grinds the back side of the substrate by chemical mechanical grinding.

[0014] According to the substrate processing apparatus of the present invention, the polishing unit includes a rotating holding section, a heating mechanism, and a polishing tool. The polishing tool contacts the back side of a rotating substrate, and polishes the back side of the substrate by chemical mechanical grinding. During this polishing process, the substrate is heated by the heating mechanism. When the substrate is heated, the polishing rate increases. Therefore, the polishing processing time can be shortened.

[0015] Furthermore, preferably, the substrate processing apparatus further includes a control unit that, during polishing, adjusts the polishing rate by controlling the heating temperature of the substrate based on the heating mechanism. By raising or lowering the heating temperature of the substrate, the polishing rate can be increased or decreased.

[0016] Furthermore, in the aforementioned substrate processing apparatus, it is preferable that the control unit also adjusts the polishing rate by controlling at least one of the contact pressure of the polishing tool on the substrate, the moving speed of the polishing tool, the rotational speed of the polishing tool, and the rotational speed of the substrate. For example, by increasing the heating temperature of the substrate while maintaining the polishing rate, the contact pressure of the polishing tool on the substrate can be reduced. This suppresses the load of the contact pressure on the substrate. That is, excessive pressure on the substrate W can be prevented.

[0017] Furthermore, preferably, the substrate processing apparatus further includes an inspection unit for inspecting the substrate, wherein the control unit detects scratches formed on the back side of the substrate by the inspection unit before grinding the back side of the substrate, and the control unit grinds the back side of the substrate when the scratches are detected by the inspection unit. This allows the detected scratches, i.e., the selected scratches, to be removed.

[0018] Furthermore, preferably, in the aforementioned substrate processing apparatus, the control unit detects scratches formed on the back side of the substrate using the inspection unit, measures the depth of the scratches upon detection, and then grinds the back side of the substrate until a thickness corresponding to the depth of the scratches measured by the inspection unit is removed. This allows for the identification of scratch depth, thus ensuring that the amount of grinding in the thickness direction of the substrate is appropriate.

[0019] Furthermore, preferably, in the above-described substrate processing apparatus, the polishing unit also includes a cleaning fluid nozzle for supplying cleaning fluid to the back surface of the substrate held by the rotating holding portion. Since the polishing unit has a cleaning function, the substrate cleaned of polishing shavings can be removed from the polishing unit.

[0020] Furthermore, preferably, the aforementioned substrate processing apparatus further includes a cleaning unit for cleaning the substrate. The cleaning unit includes: a second holding and rotating portion that rotates the substrate while it is held in a horizontal position; and a second cleaning fluid nozzle that supplies cleaning fluid to the back surface of the substrate held by the second holding and rotating portion. Thus, by providing the cleaning unit separately from the polishing unit, the polishing unit and the cleaning unit can be configured compactly, for example.

[0021] Furthermore, preferably, the substrate processing apparatus further includes a flipping unit for flipping the substrate, and the holding and rotating part holds the substrate that has been flipped by the flipping unit with its back side facing upwards. Backside grinding can then be performed on the substrate with its back side facing upwards.

[0022] Furthermore, preferably, in the aforementioned substrate processing apparatus, the holding and rotating part includes: a rotating base capable of rotating about a rotation axis extending in the vertical direction; three or more retaining pins configured to be arranged in a ring shape on the upper surface of the rotating base in a manner surrounding the rotation axis, and holding the substrate separately from the upper surface of the rotating base by clamping the side surface of the substrate; and a gas ejection port, which opens on the upper surface of the rotating base, is provided at the center of the rotating base, and ejects gas in a manner that allows gas to flow from the center side of the substrate to the periphery of the substrate in the gap between the substrate and the rotating base. The device surface (surface) of the substrate faces the rotating base. When gas is ejected from the gas ejection port, gas is ejected to the outside from the gap between the outer edge of the substrate and the rotating base. Therefore, for example, grinding debris and liquid are prevented from adhering to the device surface of the substrate. That is, the device surface of the substrate can be protected.

[0023] Invention Effects

[0024] The substrate processing apparatus according to the present invention can shorten the grinding process time. Attached Figure Description

[0025] [ Figure 1 [This is a top view showing the configuration of the substrate processing apparatus of Embodiment 1.]

[0026] [ Figure 2 Figures (a) to (d) are used to illustrate the flip unit.

[0027] [ Figure 3 [This is a side view showing the configuration of the grinding unit.]

[0028] [ Figure 4 (a) is a top view showing the structure of the retaining rotation part; (b) is a longitudinal sectional view showing a partial enlarged view of the structure of the retaining rotation part.

[0029] [ Figure 5 [ ] is a diagram showing the configuration of the grinding mechanism of the grinding unit.

[0030] [ Figure 6 [ ] is a diagram showing the structure of the inspection unit.

[0031] [ Figure 7 [ ] is a flowchart illustrating the operation of the substrate processing apparatus of Embodiment 1.

[0032] [ Figure 8 (a) is a schematic longitudinal sectional view of the substrate before the etching process; (b) is a schematic longitudinal sectional view of the substrate after the etching process (before the back-side grinding process); (c) is a schematic longitudinal sectional view of the substrate after the back-side grinding process.

[0033] [ Figure 9 [ ] is a flowchart showing the details of the wet etching process.

[0034] [ Figure 10 [1] is a graph showing the relationship between the heating temperature of the substrate and the polishing rate.

[0035] [ Figure 11 [This is a flowchart showing the details of the substrate cleaning process.]

[0036] [ Figure 12 [ ] is a flowchart illustrating the operation of the substrate processing apparatus of Embodiment 2.

[0037] [ Figure 13 The graph shows the relationship between the heating temperature of the substrate and the contact pressure (pressing) of the polishing tool.

[0038] [ Figure 14 [This is a side view showing the configuration of the grinding unit in Embodiment 4.]

[0039] [ Figure 15 [This is a side view showing the configuration of the liquid treatment unit of Example 4.]

[0040] [ Figure 16 (a) and (b) are diagrams showing heaters used to heat grinding tools.

[0041] [ Figure 17 [1] is a graph showing the relationship between the combination of heating mechanisms and the heating temperature of the substrate. Detailed Implementation

[0042] Example 1

[0043] Hereinafter, Embodiment 1 of the present invention will be described with reference to the accompanying drawings. Figure 1 This is a top view showing the configuration of the substrate processing apparatus of Embodiment 1.

[0044] (1) Composition of substrate processing device

[0045] Reference Figure 1 The substrate processing apparatus 1 includes a sorting block 3 and a processing block 5. Furthermore, the block is also referred to as a region.

[0046] The indexer block 3 includes multiple (e.g., four) carrier platforms 7 and an indexer robot 9. The four carrier platforms 7 are disposed on the outer surface of the housing 10. Each of the four carrier platforms 7 is an object that holds a carrier C. The carrier C houses multiple substrates W. Each substrate W within the carrier C is in a horizontal orientation with its device face up. The carrier C uses, for example, a front-open unified pod (FOUP), an SMIF (Standard Mechanical Interface) wafer cassette, or an open wafer cassette. The substrates W are silicon substrates, formed, for example, in a circular shape.

[0047] The indexing robot 9 removes the substrate W from the carrier C placed on each carrier platform 7, and then stores the substrate W back into the carrier C. The indexing robot 9 is disposed inside the housing 10. The indexing robot 9 has two hands 11 (11A, 11B), two articulated arms 13, 14, a lifting platform 15, and a guide rail 16. The two hands 11 hold the substrate W respectively. The first hand 11A is connected to the front end of the articulated arm 13. The second hand 11B is connected to the front end of the articulated arm 14.

[0048] The two articulated arms 13 and 14 are, for example, of the SCARA type. The base ends of each of the two articulated arms 13 and 14 are mounted on a lifting platform 15. The lifting platform 15 is configured to extend and retract in the vertical direction. Thus, the two hands 11 and the two articulated arms 13 and 14 can be raised and lowered. The lifting platform 15 is rotatable about a central axis AX1 extending in the vertical direction. This allows the orientation of the two hands 11 and the two articulated arms 13 and 14 to be changed. The lifting platform 15 of the indexing robot 9 can move along a guide rail 16 extending in the Y direction.

[0049] The indexing robot 9 is equipped with multiple electric motors. The indexing robot 9 is driven by multiple electric motors. The indexing robot 9 transports the substrate W between the carrier C placed on each of the four carrier platforms 7 and the flipping unit RV described later.

[0050] Processing block 5 includes a transport space 18, a substrate transport robot CR, a flipping unit RV, and multiple (e.g., 8) processing units (processing chambers) U1 to U4. Figure 1 In this configuration, each processing unit U1 to U4 is arranged in, for example, two layers in the vertical direction. Processing unit U1 is an inspection unit 20. Processing units U2, U3, and U4 are grinding units 22. The number and type of processing units can be appropriately changed.

[0051] A substrate transport robot CR and a flipping unit RV are configured in the transport space 18. The flipping unit RV is positioned between the indexing robot 9 and the substrate transport robot CR. Processing units U1 and U3 are arranged along the transport space 18 in the X direction. Additionally, processing units U2 and U4 are arranged along the transport space 18 in the X direction. The transport space 18 is positioned between processing units U1 and U3 and processing units U2 and U4.

[0052] The substrate transport robot CR is configured in a manner largely similar to that of the indexing robot 9. That is, the substrate transport robot CR has two hands 24. It should be noted that other configurations of the substrate transport robot CR are labeled with the same reference numerals as those of the indexing robot 9. Unlike the lifting platform 15 of the indexing robot 9, the lifting platform 15 of the substrate transport robot CR is fixed to the ground. However, it is also possible that the lifting platform 15 of the substrate transport robot CR has a guide rail extending in the X direction, enabling it to move in the X direction. The substrate transport robot CR transports substrates W between the flipping unit RV and the eight processing units U1 to U4.

[0053] (1-1) Flip unit RV

[0054] Figure 2 (a)~ Figure 2 Figure (d) illustrates the flipping unit RV. The flipping unit RV includes a support member 26, mounting members 28A and 28B, clamping members 30A and 30B, a sliding shaft 32, and multiple electric motors (not shown). Mounting members 28A and 28B are respectively provided on the left and right support members 26. Clamping members 30A and 30B are respectively provided on the left and right sliding shafts 32. Multiple electric motors drive the support member 26 and the sliding shafts 32. It should be noted that the mounting members 28A and 28B and the clamping members 30A and 30B are positioned in a non-interfering manner.

[0055] Reference Figure 2 (a) A substrate W, for example, conveyed by an indexing robot 9, is placed on mounting components 28A and 28B. (See reference...) Figure 2 (b) The left and right sliding shafts 32 move closer to each other along the horizontal axis AX2. Thus, the clamping members 30A and 30B clamp the two substrates W. (See reference...) Figure 2 (c) Then, the left and right mounting members 28A and 28B separate and descend. Then, the clamping members 30A and 30B rotate 180° around the horizontal axis AX2. As a result, each substrate W is flipped.

[0056] Reference Figure 2(d) Then, the left and right mounting members 28A and 28B move closer to each other while rising. Then, the left and right sliding shafts 32 separate from each other along the horizontal axis AX2. As a result, the clamping members 30A and 30B release the clamping of the two substrates W, and the two substrates W are placed on the mounting members 28A and 28B. Figure 2 (a)~ Figure 2 In (d), the flipping unit RV can flip two substrates W, but the flipping unit RV can also be configured to flip three or more substrates W.

[0057] (1-2) Grinding unit 22

[0058] Figure 3 This diagram shows the polishing unit 22. The polishing unit 22 includes a holding and rotating part 35, a polishing mechanism 37, and a substrate thickness measuring device 39. The holding and rotating part 35 corresponds to the holding and rotating part of the present invention.

[0059] The holding and rotating part 35 holds a substrate W in a horizontal position with the back side of the substrate W facing upwards, and rotates the held substrate W. Here, the back side of the substrate W refers to the side of the substrate W from which the electronic circuit is not formed (device side), i.e., the surface of the substrate W. The device side of the substrate W held in the holding and rotating part 35 faces downwards.

[0060] The rotating part 35 includes a rotating base 41, six retaining pins 43, a hot plate 45, and a gas outlet 47. The rotating base 41 is formed in the shape of a circular plate and is arranged in a horizontal position. A rotation axis AX3 extending in the vertical direction passes through the center of the rotating base 41. The rotating base 41 is capable of rotating about the rotation axis AX3.

[0061] Figure 4 (a) is a top view showing the rotating base 41 holding the rotating part 35 and the six retaining pins 43. The six retaining pins 43 are provided on the upper surface of the rotating base 41. The six retaining pins 43 are arranged in a ring around the rotating shaft AX3. In addition, the six retaining pins 43 are provided at equal intervals on the outer edge of the rotating base 41. The six retaining pins 43 hold the substrate W separately from the rotating base 41 and the hot plate 45 described later. Moreover, the six retaining pins 43 are configured to clamp the side of the substrate W. That is, the six retaining pins 43 can hold the substrate W separately from the upper surface of the rotating base 41.

[0062] The six retaining pins 43 are divided into three retaining pins 43A that rotate and three retaining pins 43B that do not rotate. The three retaining pins 43A are rotatable about a rotation axis AX4 extending vertically. By rotating each retaining pin 43A about the rotation axis AX4, the three retaining pins 43A hold the substrate W and release the held substrate W. The rotation of each retaining pin 43A about the rotation axis AX4 is achieved, for example, by magnetic attraction or repulsion based on magnets. The number of retaining pins 43 is not limited to six; three or more are acceptable. The substrate W can also be held using three or more retaining pins 43, including the rotating retaining pins 43A and the non-rotating retaining pins 43B.

[0063] A hot plate 45 is provided on the upper surface of the rotating base 41. The hot plate 45 contains, for example, an electric heater with nickel-chromium alloy wire. The hot plate 45 is formed in a donut shape and a round plate shape. The hot plate 45 heats the substrate W using radiant heat. Furthermore, since the hot plate 45 also heats the gas ejected from the gas outlet 47 (described later), the substrate W is heated via this gas. The temperature of the substrate W is measured using a non-contact temperature sensor 46. The temperature sensor 46 includes a detection element that detects infrared radiation emitted by the substrate W. It should be noted that the hot plate 45 corresponds to the heating mechanism of the present invention. Additionally, in Embodiment 1, the grinding unit 22 does not include the heaters 147 and 154 (see [link to embodiment]). Figure 3 ).

[0064] A shaft 49 is provided on the lower surface of the rotating base 41. The rotating mechanism 51 has an electric motor. The rotating mechanism 51 rotates the shaft 49 about the rotating axis AX3. That is, the rotating mechanism 51 rotates the substrate W, which is held by six retaining pins 43 (specifically three retaining pins 43A) provided on the rotating base 41, about the rotating axis AX3.

[0065] Reference Figure 3 and Figure 4 (b) A gas outlet 47 is opened on the upper surface of the rotating base 41 and is located at the center of the rotating base 41. A flow path 53 with an upper opening is provided at the center of the rotating base 41. In addition, an ejection member 57 is provided in the flow path 53 by means of a plurality of spacers 55. The gas outlet 47 is formed by an annular opening, which is formed by the gap between the ejection member 57 and the flow path 53.

[0066] The gas supply pipe 59 is configured to pass through the shaft 49 and the rotating mechanism 51 along the rotation axis AX3. Gas (e.g., inactive gas such as nitrogen) is supplied from the gas supply source 63 to the gas supply pipe 59 via the gas supply pipe 61. An on / off valve V1 is provided on the gas pipe 61. The on / off valve V1 controls the supply and stop of gas. When the on / off valve V1 is open, gas is ejected from the gas outlet 47. When the on / off valve V1 is closed, gas is not ejected from the gas outlet 47. The gas outlet 47 ejects gas in such a manner that gas flows from the center side of the substrate W to the outer edge of the substrate W within the gap between the substrate W and the rotating base 41.

[0067] Next, the composition for supplying the chemical solution, rinsing solution, and gas will be described. The grinding unit 22 includes a first chemical solution nozzle 65, a second chemical solution nozzle 67, a first cleaning solution nozzle 69, a second cleaning solution nozzle 71, a rinsing solution nozzle 73, and a gas nozzle 75.

[0068] It should be noted that the first cleaning fluid nozzle 69, the second cleaning fluid nozzle 71, and the rinsing fluid nozzle 73 are equivalent to the cleaning fluid nozzles of the present invention.

[0069] A liquid supply pipe 78 is connected to the first liquid nozzle 65 for conveying a first liquid from a first liquid supply source 77. The first liquid is, for example, fluorinated acid (HF). An on / off valve V2 is provided on the liquid supply pipe 78. The on / off valve V2 controls the supply and cessation of the first liquid. When the on / off valve V2 is open, the first liquid is supplied from the first liquid nozzle 65. Conversely, when the on / off valve V2 is closed, the supply of the first liquid from the first liquid nozzle 65 is stopped.

[0070] A liquid supply pipe 81 is connected to the second liquid nozzle 67 for conveying a second liquid from a second liquid supply source 80. The second liquid is, for example, a mixture of hydrofluoric acid (HF) and nitric acid (HNO3), TMAH (tetramethylammonium hydroxide), or diluted hot ammonia water (Hot-dNH4OH). An on / off valve V3 is provided on the liquid supply pipe 81. The on / off valve V3 controls the supply and cessation of the second liquid.

[0071] A cleaning fluid pipe 84 is connected to the first cleaning fluid nozzle 69 for supplying first cleaning fluid from a first cleaning fluid supply source 83. The first cleaning fluid is, for example, SC2 or SPM. SC2 is a mixture of hydrochloric acid (HCl), hydrogen peroxide (H2O2), and water. SPM is a mixture of sulfuric acid (H2SO4) and hydrogen peroxide (H2O2). An on / off valve V4 is provided on the cleaning fluid pipe 84. The on / off valve V4 controls the supply and stop of the first cleaning fluid.

[0072] A cleaning fluid pipe 87 is connected to the second cleaning fluid nozzle 71 for supplying second cleaning fluid from a second cleaning fluid supply source 86. The second cleaning fluid is, for example, SC1. SC1 is a mixture of ammonia, hydrogen peroxide (H2O2), and water. An on / off valve V5 is provided on the cleaning fluid pipe 87. The on / off valve V5 controls the supply and cessation of the second cleaning fluid.

[0073] A rinsing fluid nozzle 73 is connected to a rinsing fluid pipe 90 for supplying rinsing fluid from a rinsing fluid supply source 89. The rinsing fluid is, for example, pure water such as DIW (Deionized Water) or carbonated water. An on / off valve V6 is provided on the rinsing fluid pipe 90. The on / off valve V6 controls the supply and stop of the rinsing fluid.

[0074] A gas pipe 93 is connected to the gas nozzle 75 for supplying gas from the gas supply source 92. The gas is an inert gas such as nitrogen. An on / off valve V7 is provided on the gas pipe 93. The on / off valve V7 controls the supply and stop of gas.

[0075] The first liquid nozzle 65 moves horizontally via a nozzle moving mechanism 95. The nozzle moving mechanism 95 is equipped with an electric motor. The nozzle moving mechanism 95 can also rotate the first liquid nozzle 65 around a predetermined vertical axis (not shown). Furthermore, the nozzle moving mechanism 95 can move the first liquid nozzle 65 in the X and Y directions. Additionally, the nozzle moving mechanism 95 can also move the first liquid nozzle 65 in the vertical direction (Z direction). Similarly, the five nozzles 67, 69, 71, 73, and 75 can each be moved via a nozzle moving mechanism (not shown).

[0076] Next, the configuration of the polishing mechanism 37 will be described. The polishing mechanism 37 polishes the back side of the substrate W. Figure 5 This is a side view showing the grinding mechanism 37. The grinding mechanism 37 includes a grinding tool 96 and a grinding tool moving mechanism 97. The grinding tool moving mechanism 97 includes a mounting component 98, a shaft 100, and an arm 101.

[0077] The grinding tool 96 grinds the back side of the substrate W using dry chemical-mechanical grinding (CMG). The grinding tool 96 is cylindrical. It has a resin body in which abrasive grains are dispersed. In other words, the grinding tool 96 is formed by fixing abrasive grains (grinding agent) with a resin binder. For example, oxides such as cerium oxide or silicon dioxide can be used as abrasive grains. The average particle size of the abrasive grains is preferably 10 μm or less. Thermosetting resins such as epoxy resin or phenolic resin are used as the resin body and resin binder. Alternatively, thermoplastic resins such as ethyl cellulose can also be used as the resin body and resin binder. In this case, grinding is performed in a manner that prevents the thermoplastic resin from softening.

[0078] Here, chemical mechanical grinding (CMG) will be explained. CMG is believed to perform grinding based on the following principle: the localized high temperature and pressure near the abrasive grains, such as cerium oxide, caused by contact between the abrasive grains and the workpiece, induces a solid-phase reaction between the abrasive grains and the workpiece, generating silicates. As a result, the surface layer of the workpiece softens, and the softened surface layer is mechanically removed by the abrasive grains. It should be noted that there is also a method called chemical mechanical polishing (CMP) in grinding. This method involves supplying a slurry solution to a pad that is in contact with the workpiece, and keeping the abrasive grains contained in the slurry solution on the uneven surface of the pad to perform chemical mechanical polishing. This invention employs the CMG method.

[0079] The grinding tool 96 can be attached to and detached from the mounting member 98 by means of, for example, screws. The mounting member 98 is fixed to the lower end of the shaft 100. A pulley 102 is fixed on the shaft 100. The upper end of the shaft 100 is received in the arm 101. That is, the grinding tool 96 and the mounting member 98 are mounted on the arm 101 via the shaft 100.

[0080] An electric motor 104 and a pulley 106 are disposed within the arm 101. The pulley 106 is connected to the rotational output shaft of the electric motor 104. A belt 108 is attached to the two pulleys 102 and 106. The pulley 106 rotates via the electric motor 104. The rotation of the pulley 106 is transmitted to the pulley 102 and the shaft 100 via the belt 108. As a result, the grinding tool 96 rotates around the vertical axis AX5.

[0081] Furthermore, the grinding tool moving mechanism 97 includes a lifting mechanism 110. The lifting mechanism 110 includes a guide rail 111, a cylinder 113, and an electric air conditioner 115. The base of the arm 101 is connected to the guide rail 111 in a lifting manner. The guide rail 111 guides the arm 101 in the vertical direction. The cylinder 113 raises and lowers the arm 101. The electric air conditioner 115 supplies the cylinder 113 with air or other gas whose pressure is set based on an electrical signal from the main control unit 134 (described later). It should be noted that the lifting mechanism 110 may replace the cylinder 113 with a linear actuator driven by an electric motor.

[0082] Furthermore, the grinding tool moving mechanism 97 includes an arm rotating mechanism 117. The arm rotating mechanism 117 is equipped with an electric motor. The arm rotating mechanism 117 rotates the arm 101 and the lifting mechanism 110 about the vertical axis AX6. That is, the arm rotating mechanism 117 rotates the grinding tool 96 about the vertical axis AX6.

[0083] The polishing unit 22 includes a substrate thickness measuring device 39. The substrate thickness measuring device 39 measures the thickness of the substrate W held by the holding and rotating part 35. The substrate thickness measuring device 39 is configured to irradiate the mirror and substrate W with light in a wavelength range (e.g., 1100 nm to 1900 nm) that is transmissible to the substrate W via an optical fiber from a light source. Furthermore, the substrate thickness measuring device 39 is configured to detect the reflected light from the mirror, the reflected light from the upper surface of the substrate W, and the reflected light from the lower surface of the substrate W, which interfere with each other, using a light-receiving element. Moreover, the substrate thickness measuring device 39 is configured to generate a beam splitting interference waveform representing the relationship between the wavelength and light intensity of the returned light, and to determine the thickness of the substrate W by performing waveform analysis on this beam splitting interference waveform. The substrate thickness measuring device 39 is a known device. The substrate thickness measuring device 39 may also be configured to move between a standby position outside the substrate and a measuring position above the substrate W via a moving mechanism (not shown).

[0084] (1-3) Inspection Unit 20

[0085] Figure 6 This is a side view showing the inspection unit 20. The inspection unit 20 includes a stage 121, an XY direction moving mechanism 122, a camera 124, an illumination 125, a laser scanning confocal microscope 127, a lifting mechanism 128, and an inspection control unit 130.

[0086] The stage 121 supports the substrate W with its back side facing upwards and in a horizontal position. The stage 121 includes a circular base member 131 and, for example, six support pins 132. The six support pins 132 are arranged in a ring around the central axis AX7 of the base member 131. Furthermore, the six support pins 132 are arranged at equal intervals in the circumferential direction. With this configuration, the six support pins 132 can support the outer edge of the substrate W even when it is detached from the base member 131. Additionally, an XY direction movement mechanism 122 moves the stage 121 in the XY direction (horizontal direction). The XY direction movement mechanism 122 includes, for example, two linear actuators driven by electric motors.

[0087] Camera 124 captures images of the back side of substrate W. Camera 124 is equipped with an image sensor such as CCD (charge-coupled device) or CMOS (complementary metal-oxide semiconductor). Illumination 125 illuminates the back side of substrate W. Thus, for example, scratches generated on the back side of substrate W can be easily observed.

[0088] Hereinafter, the laser scanning confocal microscope 127 will be referred to as "laser microscope 127". The laser microscope 127 includes a laser source, an objective lens 127A, an imaging lens, a light sensor, and a confocal optical system with a confocal pinhole. The laser microscope 127 acquires planar images by scanning the laser source in the XY direction (horizontal direction). Furthermore, the laser microscope 127 acquires planar images while moving the objective lens 127A relative to the object being observed in the Z direction (height direction). As a result, the laser microscope 127 acquires three-dimensional images (multiple planar images) containing three-dimensional shapes. It should be noted that the laser microscope 127 is referred to as a three-dimensional shape measuring device.

[0089] The laser microscope 127 acquires a three-dimensional image of an arbitrary scratch generated on the back side of the substrate W. For example, the control unit, described later, determines the depth of the scratch from the three-dimensional shape of the scratch in the acquired three-dimensional image. The lifting mechanism 128 moves the laser microscope 127 up and down in the vertical direction (Z direction). The lifting mechanism 128 is composed of a linear actuator driven by an electric motor.

[0090] The inspection control unit 130 includes one or more processors, such as a central processing unit (CPU), and a storage unit (not shown). The inspection control unit 130 controls each component of the inspection unit 20. The storage unit of the inspection control unit 130 includes at least one of ROM (Read-only Memory), RAM (Random-Access Memory), and a hard disk. The storage unit of the inspection control unit 130 stores computer programs for operating the inspection unit 20, observed images, scratch extraction results, and three-dimensional images.

[0091] Furthermore, the substrate processing apparatus 1 includes a main control unit 134 and a storage unit (not shown) that are communicatively connected to the inspection control unit 130. The main control unit 134 includes one or more processors, such as a central processing unit (CPU). The main control unit 134 controls various components of the substrate processing apparatus 1. Additionally, the storage unit of the main control unit 134 includes at least one of ROM (Read-only Memory), RAM (Random-Access Memory), and a hard disk. The storage unit of the main control unit 134 stores computer programs and the like for operating the substrate processing apparatus 1. The main control unit 134 corresponds to the control unit of the present invention.

[0092] (2) Operation of substrate processing device 1

[0093] Next, refer to Figure 7 The operation of the substrate processing apparatus 1 will be explained.

[0094] [Step S01] The substrate W is removed from the carrier C.

[0095] A carrier C is placed on a designated carrier platform 7. The indexing robot 9 removes the substrate W from the carrier C and transports the removed substrate W to the flipping unit RV. At this time, the device side of the substrate W is facing upwards, and the back side of the substrate W is facing downwards.

[0096] [Step S02] Flipping of substrate W

[0097] If one or two substrates W are placed on the mounting components 28A and 28B by the indexing robot 9, then as Figure 2 (a)~ Figure 2 As shown in (d), the flipping unit RV flips the two substrates W. Thus, the back side of substrate W faces upward.

[0098] The substrate transport robot CR removes substrate W from the flipping unit RV and transports substrate W to one of the two inspection units 20. Figure 6 The stage 121 of the inspection unit 20 shown holds the substrate W with its back side facing upward.

[0099] [Step S03] Scratch observation

[0100] Inspection unit 20 inspects the back side of substrate W. Inspection unit 20 detects scratches, particles, and other protrusions. In this embodiment, the detection of scratches formed on the back side of substrate W will be described in particular.

[0101] exist Figure 6 In the inspection unit 20 shown, illumination 125 shines light towards the back side of the substrate W. Camera 124 captures an image of the back side of the substrate W illuminated by the light. The image can be captured by camera 124 while the stage 121 holding the substrate W is moved using the XY direction movement mechanism 122. The acquired image shows scratches of varying sizes. Inspection control unit 130 performs image processing on the image, designating areas with relatively strong reflected light (i.e., areas with brightness exceeding a preset threshold) as polishing targets, and extracting one or more scratches. Alternatively, inspection control unit 130 can also extract scratches from polishing targets based on the length of the scratches.

[0102] Furthermore, when a scratch is detected, the inspection unit 20 measures the depth of the scratch. For example, when multiple scratches are inspected (extracted), the inspection unit 20 measures the depth of one or more representative scratches. The method of measuring the depth of the scratch will be explained.

[0103] Lifting mechanism 128 ( Figure 6 The laser microscope 127 is lowered to a predetermined height. Based on this, the XY direction movement mechanism 122 moves the stage 121 so that the scratch on the object being measured is located below the objective lens 127A of the laser microscope 127. The movement of the stage 121 is based on the coordinates of the scratch extracted from the observed image. The laser microscope 127 illuminates the scratch (entirely or partially) and its periphery with laser light from the objective lens 127A, while simultaneously collecting the reflected light through the objective lens 127A. As a result, the laser microscope 127 acquires a three-dimensional image containing the three-dimensional shape.

[0104] The inspection control unit 130 performs image processing on the three-dimensional image to determine the depth of the scratch. Figure 8 (a) is a longitudinal sectional view illustrating the state of the substrate W before the etching process. Figure 8 In (a), for example, a thin film such as a silicon oxide film, a silicon nitride film, or polycrystalline silicon is formed on the back side of the substrate W. Additionally, it is set that... Figure 8 In (a), the scratch SH1 on the left side reaches the bare silicon BSi. In this case, the inspection control unit 130 determines the depth (value DP1) of the scratch SH1 based on the three-dimensional image obtained by the laser microscope 127.

[0105] After inspecting for scratches, etc., the substrate transfer robot CR moves the substrate W from the stage 121 of the inspection unit 20 to one of the six polishing units 22 (U2 to U4). The substrate W, with its back side facing up, is placed on the holding and rotating part 35 of the polishing unit 22. Then, a magnet (not shown) is used to... Figure 4 The three retaining pins 43A shown in (a) rotate about the rotation axis AX4. Thus, the three retaining pins 43A hold the substrate W. Here, the substrate W is held in a state separated from the rotating base 41 and the hot plate 45.

[0106] Here, prior to the subsequent wet etching process, the substrate thickness measuring device 39 measures the thickness of the substrate W. Figure 8 The thickness TK1 of the substrate W as shown in (a).

[0107] [Step S04] Wet etching

[0108] If a thin film such as a silicon oxide film, silicon nitride film, or polycrystalline silicon film is formed on the back side of the substrate W, it is not possible to effectively polish the back side of the substrate W using the polishing tool 96. Some of these films are unintentionally formed during the device manufacturing process, while others are intentionally formed to suppress warping of the substrate W. Therefore, the polishing unit 22 removes the film FL formed on the back side of the substrate W by supplying a first solution (etching solution) to the back side of the substrate W.

[0109] Figure 9 This is a flowchart illustrating the details of the wet etching process in step S04. First, the silicon oxide film and silicon nitride film are removed (step S21).

[0110] Here, gas is ejected from the gas outlet 47 located at the center of the rotating base 41. That is, gas is ejected from the gas outlet 47 in such a way that gas flows from the center of the substrate W towards the outer edge of the substrate W within the gap between the substrate W and the rotating base 41. The device surface (surface) of the substrate W faces the rotating base 41. When gas is ejected from the gas outlet 47, gas is ejected outward from the gap between the outer edge of the substrate W and the rotating base 41. This prevents liquids such as polishing shavings and the first chemical solution from adhering to the device surface of the substrate W. In other words, the device surface is protected. Furthermore, due to the Bernoulli effect, the force that aims to adhere the substrate W to the rotating base 41 is activated.

[0111] The nozzle moving mechanism 95 moves the first liquid nozzle 65 from a standby position outside the substrate to any processing position above the substrate W. The holding rotating part 35 rotates the substrate W while keeping it in a horizontal position. Then, a first liquid (e.g., hydrofluoric acid) is supplied from the first liquid nozzle 65 to the back surface of the rotating substrate W. This allows the removal of the silicon oxide and silicon nitride films formed on the back surface of the substrate W.

[0112] It should be noted that the first liquid can be supplied while the first liquid nozzle 65 is moved horizontally. In addition, after the supply of the first liquid from the first liquid nozzle 65 is stopped, the first liquid nozzle 65 moves to a standby position outside the substrate.

[0113] Next, a rinsing process is performed (step S22). That is, rinsing liquid (e.g., DIW or carbonated water) is supplied from the rinsing liquid nozzle 73 to the center of the rotating substrate W. This rinses away the first solution remaining on the back side of the substrate W. Next, a drying process is performed (step S23). That is, the supply of rinsing liquid from the rinsing liquid nozzle 73 is stopped. Then, the rotating part 35 is kept rotating the substrate W at high speed to dry the substrate W. At this time, gas can also be supplied to the back side of the substrate W from the gas nozzle 75, which has moved above the substrate W. It should be noted that the drying process can also be performed by supplying gas from the gas nozzle 75 without rotating the substrate W at high speed.

[0114] After steps S21 to S23, a polysilicon film removal process is performed (step S24). The second chemical nozzle 67 is moved from a standby position outside the substrate to any processing position above the substrate W. The rotating part 35 is held to rotate the substrate W at a preset rotation speed. Then, a second chemical solution (e.g., a mixture of fluorine acid (HF) and nitric acid (HNO3)) is supplied from the second chemical nozzle 67 to the back side of the rotating substrate W. As a result, the polysilicon film formed on the back side of the substrate W can be removed.

[0115] The second liquid can also be supplied while the second liquid nozzle 67 is moved horizontally. In addition, after the supply of the second liquid from the second liquid nozzle 67 is stopped, the second liquid nozzle 67 moves to a standby position outside the substrate.

[0116] Then, similarly to the case of the first solution (steps S22 and S23), a rinsing process is performed (step S25), followed by a drying process (step S26). The rotating part 35 is held in place to stop the rotation of the substrate W.

[0117] [Step S05] Grinding the back side of substrate W

[0118] After the wet etching process, the polishing unit 22 polishes the back side of the substrate W. This polishing is performed by the inspection unit 20 on the back side of the substrate W, especially when scratches are detected. A detailed explanation follows.

[0119] The substrate W is rotated while the rotating part 35 remains in a horizontal position. The arm rotation mechanism 117 of the grinding mechanism 37 ( Figure 5The polishing tool 96 and arm 101 are rotated around the vertical axis AX6. This moves the polishing tool 96 from a standby position outside the substrate to a predetermined position above the substrate W. Additionally, the electric motor 104 of the polishing mechanism 37 rotates the polishing tool 96 around the vertical axis AX5 (axis 100).

[0120] Additionally, the hot plate 45 heats the substrate W by generating heat through an energized circuit. The temperature of the substrate W is monitored by a non-contact temperature sensor 46. The main control unit 134 adjusts the heating based on the temperature of the substrate W detected by the temperature sensor 46. To achieve a high polishing rate, the heating temperature of the substrate W is adjusted to be higher than room temperature (e.g., 25°C). However, to avoid thermal degradation of the polishing tool 96, it is preferable to adjust it to below 100°C.

[0121] Subsequently, the electric air conditioner 115 supplies gas with pressure based on an electrical signal to the cylinder 113. This causes the cylinder 113 to lower the polishing tool 96 and arm 101, bringing the polishing tool 96 into contact with the back surface of the substrate W. The polishing tool 96 is pressed against the back surface of the substrate W with a preset contact pressure. This performs polishing. During polishing, the arm rotation mechanism 117 of the polishing mechanism 37 (… Figure 5 The polishing tool 96 and arm 101 are oscillated about the vertical axis AX6. That is, the polishing tool 96 repeatedly performs reciprocating motion between the center side and the outer edge side of the back surface of the substrate W.

[0122] Furthermore, regarding the amount of grinding in the thickness direction (Z direction) of substrate W, even if scratches exist, grinding is considered unnecessary if substrate W meets a predetermined flatness. However, the edges of scratches may cause new damage to, for example, the stage of an exposure machine. Therefore, grinding continues until scratches of a predetermined size disappear.

[0123] like Figure 8 As shown in (a), the depth (value DP1) of the scratch SH1 is obtained by the laser microscope 127. Therefore, the polishing unit 22 polishes the back side of the substrate W until the thickness corresponding to the depth (value DP1) of the scratch SH1 measured by the laser microscope 127 is removed. The thickness corresponding to the depth of the scratch SH1 is the value DP1. Polishing is performed until the thickness of the substrate W becomes the value TK2 (=TK1-DP1). The thickness of the substrate W is periodically measured by the substrate thickness measuring device 39. The main control unit 134 compares the measured value of the substrate thickness with a target value (e.g., value TK2) and controls the process to continue polishing if the measured value does not reach the target value.

[0124] It should be noted that, Figure 8(b) is a diagram showing the state after the etching process (step S04). If the film FL is removed by the etching process, the depth of the scratch SH1 becomes shallower. Therefore, the amount of grinding in the vertical direction is reduced, but the grinding continues until the thickness of the substrate W is TK2, which remains unchanged. Figure 8 (c) is a diagram showing the state after the grinding process (step S05). It should be noted that... Figure 8 The scratch SH2 shown in (a) did not reach the bare silicon. Such scratches are removed along with the removal of films such as silicon oxide films (FL).

[0125] The substrate W is heated by the hot plate 45. Figure 10 This is a graph showing the relationship between the heating temperature of the substrate W and the polishing rate. The contact pressure of the polishing tool 96 and the rotational speed of the substrate W are constant. Here, compared to the case where the temperature of the substrate W is, for example, room temperature (e.g., 25°C), the polishing rate increases when the temperature TM2 of the substrate W is increased. Therefore, by heating the substrate W using the hot plate 45, the polishing rate can be increased. Thus, the polishing process time can be shortened.

[0126] During polishing, the polishing unit 22 can also adjust the polishing rate by controlling the heating temperature of the substrate W based on the hot plate 45. The polishing rate can be adjusted by raising or lowering the heating temperature of the substrate W. The polishing rate can be adjusted before or during polishing. For example, by varying the temperature of the substrate W between its center and outer edges, different polishing rates can be achieved between the center and outer edges of the substrate W. It should be noted that the polishing tool 96 moves to the standby position of the substrate W.

[0127] [Step S06] Cleaning of substrate W

[0128] After the back side of substrate W is polished, the back side of substrate W is cleaned. This removes polishing debris remaining on the back side of substrate W, as well as metals, organic matter, and particles. Figure 11 This is a flowchart showing the details of the cleaning process in step S06.

[0129] First, a first cleaning solution is supplied to the back side of the substrate W (step S31). This will be explained in detail. The holding and rotating unit 35 maintains the state of holding the substrate W. Furthermore, the holding and rotating unit 35 maintains the state of protecting the device surface of the substrate W by ejecting gas from the gas ejection port 47. The first cleaning solution nozzle 69 is moved from a standby position outside the substrate to any processing position above the substrate W. The holding and rotating unit 35 rotates the substrate W. Then, a first cleaning solution (e.g., SC2 or SPM) is supplied from the first cleaning solution nozzle 69 to the back side of the rotating substrate W. The first cleaning solution can be supplied while the first cleaning solution nozzle 69 is moved horizontally.

[0130] After supplying the first cleaning solution and performing the cleaning process, a rinsing process is performed (step S32). That is, rinsing solution (DIW or carbonated water) is supplied from the rinsing solution nozzle 73 to the center of the rotating substrate W. This washes away the first cleaning solution remaining on the back side of the substrate W. After that, a drying process is performed (step S33). That is, the supply of rinsing solution from the rinsing solution nozzle 73 is stopped. Then, the rotating part 35 is kept in operation to dry the substrate W by rotating it at high speed. At this time, gas can also be supplied to the back side of the substrate W from the gas nozzle 75, which has moved above the substrate W. It should be noted that the drying process can also be performed by supplying gas from the gas nozzle 73 without rotating the substrate W at high speed.

[0131] After steps S31 to S33, a second cleaning fluid is supplied (step S34). That is, the second cleaning fluid nozzle 71 is moved from a standby position outside the substrate to any processing position above the substrate W. The rotating part 35 is held to rotate the substrate W at a preset rotation speed. Then, a second cleaning fluid (e.g., SC1) is supplied from the second cleaning fluid nozzle 71 to the back side of the rotating substrate W.

[0132] The second cleaning fluid can be supplied while the second cleaning fluid nozzle 71 is moved horizontally. After the supply of the second cleaning fluid from the second cleaning fluid nozzle 71 is stopped, the second cleaning fluid nozzle 71 moves to a standby position outside the substrate.

[0133] Then, similarly to the case of the first cleaning solution (steps S32 and S33), a rinsing process is performed (step S35), followed by a drying process (step S36). The rotating part 35 is kept stationary to stop the rotation of the substrate W. Since the polishing unit 22 of this embodiment has a cleaning function, the substrate W, after being cleaned of polishing debris, can be removed from the polishing unit 22.

[0134] [Step S07] Flipping of substrate W

[0135] The substrate transfer robot CR removes the substrate W from the grinding unit 22 and transfers it to the flipping unit RV. At this time, the back side of the substrate W faces upwards, and the device side of the substrate W faces downwards. If one or two substrates W are placed on the mounting components 28A and 28B by the substrate transfer robot CR, then as follows... Figure 2 (a)~ Figure 2 As shown in (d), the flipping unit RV flips the two substrates W. Thus, the back side of substrate W faces down.

[0136] [Step S08] The substrate W is placed into the carrier C.

[0137] The indexing robot 9 removes the substrate W from the flipping unit RV and returns the substrate W to the carrier C.

[0138] According to this embodiment, the polishing unit 22 includes a rotating holding section 35, a hot plate 45 (heating mechanism), and a polishing tool 96. The polishing tool 96 contacts the back side of the rotating substrate W and polishes the back side of the substrate W by chemical mechanical grinding (CMG). During this polishing, the substrate W is heated by the hot plate 45. If the substrate W is heated, the polishing rate can be increased (see...). Figure 10 Therefore, the grinding process time can be shortened.

[0139] Furthermore, before polishing the back side of the substrate W, the inspection unit 20 inspects the substrate W to detect scratches formed on the back side of the substrate W. When the inspection unit 20 detects a scratch, the back side of the substrate W is polished. This allows the detected scratches, i.e., the selected scratches, to be removed.

[0140] Furthermore, when the inspection unit 20 detects a scratch, it measures the depth of the scratch. The polishing unit 22 polishes the back side of the substrate W until the thickness corresponding to the scratch depth measured by the inspection unit 20 is removed. Thus, since the scratch depth is identified, the amount of polishing in the thickness direction of the substrate W can be appropriate.

[0141] According to the substrate processing apparatus 1, the polishing tool 96 is brought into contact with the back side of the rotating substrate W, and the back side of the substrate W is polished by chemical mechanical polishing (CMG). It is known that when a film FL is formed on the back side of the substrate W, polishing cannot be performed effectively due to the film FL. Therefore, an etching process is performed before polishing to remove the film FL formed on the back side of the substrate W. This allows for effective polishing.

[0142] Example 2

[0143] Next, Embodiment 2 of the present invention will be described with reference to the accompanying drawings. It should be noted that descriptions that are repeated in Embodiment 1 are omitted. Figure 12 This is a flowchart illustrating the operation of the substrate processing apparatus of Embodiment 2.

[0144] In Example 1, no scratch observation was performed after backside grinding of substrate W (step S05). In Example 2, however, scratch observation was performed after grinding. Figure 12 Step S51).

[0145] It should be noted that, Figure 12 In steps S01 to S08 shown, the following steps are performed: Figure 7 The steps S01 to S08 shown are roughly the same. After the cleaning process of the substrate W (step S06), the substrate transfer robot CR takes the substrate W out of the grinding unit 22 and transfers the substrate W to the stage 121 of one of the two inspection units 20.

[0146] [Step S51] Observation of scratches after grinding

[0147] Inspection unit 20 specifically re-inspects the scratches formed on the back side of substrate W. That is, similar to the operation in step S03, inspection unit 20 acquires an observation image using camera 124 and illumination 125. Inspection control unit 130 performs image processing on the acquired observation image to extract the scratches on the object to be polished. If the scratches on the object to be polished cannot be extracted, main control unit 134 determines that further polishing is unnecessary and proceeds to step S07.

[0148] In contrast, when scratches are detected on the object to be polished, the main control unit 134 determines that further polishing is required. Furthermore, the inspection unit 20 measures the depth of the scratches on the object to be polished. Specifically, the laser microscope 127 acquires a three-dimensional image containing the scratches on the object to be polished. The inspection control unit 130 performs image processing on the acquired three-dimensional image and measures the depth of the scratches on the object to be polished. Figure 8 The value of (b) is DP3).

[0149] Next, the substrate transfer robot CR transfers the substrate W from the stage 121 of the inspection unit 20 to the holding and rotating part 35 of the polishing unit 22. After transfer, the substrate W is held by the holding and rotating part 35, and gas is ejected from the gas ejection port 47. Then, the substrate thickness measuring device 39 moves above the substrate W and measures the thickness of the substrate W. Figure 8 The value of (b) is TK3). Return to step S05.

[0150] In step S05, while the inspection unit 20 extracts the scratches on the object to be polished, the polishing unit 22 performs backside polishing on the substrate W again. Polishing continues until the thickness (value DP3) corresponding to the depth of the scratches is removed. In other words, polishing continues until the thickness of the substrate W is... Figure 8 Up to the value TK2 (=TK3-DP3) shown in (b).

[0151] According to this embodiment, grinding is performed until the scratches on the object to be ground disappear, thus preventing new scratches from forming at the edges of the scratches, for example, on the stage of the exposure machine.

[0152] In addition, in this embodiment, the wet etching process (step S04) is not performed if there are scratches on the object being polished. However, wet etching may be performed as needed.

[0153] Example 3

[0154] Next, Embodiment 3 of the present invention will be described with reference to the accompanying drawings. It should be noted that descriptions that are repeated in Embodiments 1 and 2 are omitted.

[0155] Figure 13 This is a graph showing the relationship between the heating temperature of the substrate W and the contact pressure (pressing) of the polishing tool 96. Figure 13 This is a graph showing the grinding rate kept constant. Figure 13 In this process, a predetermined polishing rate RA is obtained when the temperature of the substrate W is at room temperature (e.g., 25°C) and a predetermined contact pressure P1 is applied. The polishing rate increases when the substrate W is heated. Therefore, if the temperature is kept above room temperature (e.g., temperature TM2) while maintaining the polishing rate RA, a contact pressure P2 lower than the contact pressure P1 can be set. That is, with the polishing rate RA constant, increasing the temperature of the substrate W can reduce the contact pressure.

[0156] According to this embodiment, the polishing unit 22 controls not only the heating temperature of the substrate W, but also the contact pressure of the polishing tool 96 on the substrate W, thereby adjusting the polishing rate. For example, by increasing the heating temperature of the substrate W while maintaining the polishing rate, the contact pressure of the polishing tool 96 on the substrate W can be reduced. This suppresses the load of the contact pressure on the substrate W, i.e., it prevents excessive pressure on the substrate W.

[0157] It should be noted that the adjustment of the grinding rate is not limited to the relationship between the heating temperature of the substrate W and the contact pressure of the grinding tool 96. That is, the grinding rate can also be adjusted based on the relationship between the heating temperature of the substrate W and the moving speed of the grinding tool 96. Furthermore, the grinding rate can also be adjusted based on the relationship between the heating temperature of the substrate W and the moving speed (oscillation speed) of the grinding tool 96 around the vertical axis AX6. The grinding rate can also be adjusted based on the relationship between the heating temperature of the substrate W and the rotational speed of the grinding tool 96 around the vertical axis AX5. Finally, the grinding rate can be adjusted based on the relationship between the heating temperature of the substrate W and the rotational speed of the substrate W.

[0158] That is, the polishing unit 22 may control, in addition to controlling the heating temperature of the substrate W, at least one of the contact pressure of the polishing tool 96 on the substrate W, the moving speed of the polishing tool 96, the rotational speed of the polishing tool 96 and the rotational speed of the substrate W, thereby adjusting the polishing rate.

[0159] Example 4

[0160] Next, Embodiment 4 of the present invention will be described with reference to the accompanying drawings. It should be noted that descriptions that are repeated in Embodiments 1 to 3 are omitted.

[0161] exist Figure 1In Example 1, processing unit U1 is inspection unit 20, and processing units U2 to U4 are grinding units 22. In Example 4, processing units U2 and U3 can be grinding units 141, and processing unit U4 can be liquid treatment unit 143. It should be noted that processing unit U1 is inspection unit 20.

[0162] That is, the substrate processing apparatus 1 of Embodiment 4 includes a 2-layer inspection unit 20, a 2-layer × 2 polishing unit 141, and a 2-layer liquid treatment unit 143. In other words, the substrate processing apparatus 1 includes 8 processing units U1 to U4. Figure 14 This is a diagram showing the grinding unit 141 of Embodiment 4. Figure 15 This is a diagram showing the liquid treatment unit 143 of Example 4.

[0163] The grinding unit 141 and the liquid treatment unit 143 are for grinding units 141 and 143 respectively. Figure 3 The grinding unit 22 shown is composed of two units. It should be noted that the liquid treatment unit 143 has a second retaining and rotating part 145 configured in the same way as the retaining and rotating part 35. In addition, the grinding unit 141 may also include a rinsing liquid nozzle 73, a rinsing liquid supply source 89, and a rinsing liquid piping 90.

[0164] It should be noted that grinding units 22 and 141 correspond to the grinding unit of the present invention. Liquid treatment unit 143 corresponds to the cleaning unit of the present invention. Second holding and rotating part 145 corresponds to the second holding and rotating part of the present invention. Furthermore, Figure 15 The first cleaning fluid nozzle 69 or the second cleaning fluid nozzle 71 shown corresponds to the second cleaning fluid nozzle of the present invention.

[0165] The operation of the substrate processing apparatus 1 is in accordance with Figure 7 or Figure 12 The flowchart shown is followed. However, for example, the substrate W is transferred between the polishing unit 141 and the liquid treatment unit 143. For example, in Figure 7 Between steps S03 and S06, the substrate W is transported by the substrate transport robot CR in the order of inspection unit 20, liquid treatment unit 143 (wet etching process), polishing unit 141, and liquid treatment unit 143 (cleaning process of substrate W).

[0166] According to this embodiment, it has the same effect as in Embodiment 1. Furthermore, since... Figure 2 The grinding unit 22 is composed of two parts, so that the grinding unit 141 and the liquid treatment unit 143 can be compactly configured respectively.

[0167] It should be noted that the configuration of the liquid treatment unit 143 involved in the wet etching process (step S04) can also be provided in the polishing unit 141. Additionally, the configuration involved in the cleaning process (step S06) of the substrate W of the liquid treatment unit 143 can also be provided in the polishing unit 141. Furthermore, in embodiment 4, the polishing unit 141 does not include the heaters 147 and 154 described later (see...). Figure 14 ).

[0168] The present invention is not limited to the above embodiments, and can be implemented in variations as described below.

[0169] (1) In the above embodiments, the polishing unit 22 includes a hot plate 45 as a heating mechanism. The polishing unit 22 may also be configured to eject heated gas from a gas outlet 47 instead of the hot plate 45. The heated gas from the gas outlet 47 can heat the substrate. In this case, for example, the polishing unit 22 may also include a heater 147 that heats the gas passing through the gas pipe 61 from the outside of the gas pipe 61 (see [link to relevant documentation]). Figure 3 , Figure 14 In this case, the grinding unit 22 may also be without the hot plate 45. Alternatively, the substrate W may be heated by both the hot plate 45 and the heating gas ejected from the gas outlet 47. The gas outlet 47 corresponds to the heating mechanism of the present invention.

[0170] (2) In the above embodiments and variations (1), the grinding unit 22 includes a hot plate 45 as a heating mechanism. Regarding this, as... Figure 16 of (a), Figure 16 As shown in (b), the grinding unit 22 may also include a heater 149 (152) for heating the grinding tool 96 instead of the hot plate 45. Alternatively, the grinding unit 22 may also include both the hot plate 45 and the heater 149 (152). Figure 16 In (a), the mounting member 98 is configured as a container with a recessed lower surface. An annular heater 149 is provided in the hollow cylindrical portion 150 surrounding the polishing tool 96 (vertical axis AX5) of the mounting member 98. The heater 149 heats the polishing tool 96. When the polishing tool 96 is heated, the substrate W can be heated via the polishing tool 96. Furthermore, the interface between the polishing tool 96 and the back surface of the substrate W can be effectively heated.

[0171] In addition, such as Figure 16As shown in (b), heater 152 can also be built into mounting component 98 and positioned between shaft 100 and grinding tool 96. It should be noted that each heater 149, 152 can also be heated by an electric heater such as a nickel-chromium alloy wire. Additionally, each heater 149, 152 can also be equipped with piping, through which heating gas or heating liquid is passed for heating. Each heater 149, 152 corresponds to the heating mechanism of the present invention.

[0172] (3) In the above embodiments and modifications, the back surface of the substrate W is polished using a polishing tool 96 via dry chemical mechanical polishing. Alternatively, the back surface of the substrate W can be polished by chemical mechanical polishing while liquid is supplied to it using the polishing tool 96. For example, liquid can be supplied from the rinsing fluid nozzle 73 ( Figure 3 , Figure 14 Heated pure water (e.g., DIW) is supplied to the back surface of the substrate W and near the polishing tool 96. The heated pure water heats the substrate W. Additionally, the heated pure water can be used to rinse away polishing debris from the back surface of the substrate W. For example, the polishing unit 22 (141) may also include a heater 154 that heats the pure water flowing through the rinsing fluid pipe 90 from the outside of the rinsing fluid pipe 90. Alternatively, the substrate W may be heated without the hot plate 45, but instead heated by the heated pure water from the rinsing fluid nozzle 73. In this case, the polishing unit 22 may not include the hot plate 45. It should be noted that the rinsing fluid nozzle 73 corresponds to the heating mechanism of the present invention.

[0173] It should be noted that the substrate W can also be heated by at least one of the following: hot plate 45, gas outlet 47 that sprays heated gas, heater 149 (or heater 152) that heats the grinding tool 96, and rinsing fluid nozzle 73 that supplies heated pure water to the back of the substrate W.

[0174] Alternatively, the polishing unit 22 may also include these heating mechanisms, and the heating temperature of the substrate W can be controlled by combining the heating mechanisms. For example, heating can be performed using only the hot plate 45. Figure 17 (Ref. H1 in the attached diagram). If further heating is desired, in addition to the hot plate 45, the substrate W can also be heated via the gas ejection port 47, which ejects heated gas. Figure 17 (Ref. H1 and H2 in the accompanying drawings). Additionally, if further heating is desired, the substrate W can be heated by a heater 149 (or heater 152) that heats the grinding tool 96, in addition to the hot plate 45 and the gas outlet 47. Figure 17(Referring to the reference numerals H1, H2, and H3). In cases where it is desired to suppress heating from this state, the substrate W (reference numeral H1) may be heated solely by the hot plate 45.

[0175] (4) In the above embodiments and variations, the substrate thickness measuring device 39 measures the thickness of the substrate W before the wet etching process (step S04). In this respect, the substrate thickness measuring device 39 can also measure the thickness of the substrate W between step S04 and the backside grinding process of the substrate W (step S05). In this case, the scratch observation process (step S03) can also be moved between steps S04 and S05.

[0176] (5) In the above embodiments and variations, the polishing unit 22 and the main control unit 134 are provided together with the indexing block 3, etc., on the substrate processing apparatus 1. In this respect, the polishing unit 22 and the main control unit 134 may also be provided in the polishing apparatus.

[0177] (6) In the above embodiments and modifications, the contact pressure of the polishing tool 96 on the substrate W can be detected, for example, by a force sensor. Additionally, the moving speed of the polishing tool 96 can be detected by a rotary encoder that detects the angle of the polishing tool 96 around the vertical axis AX6. Furthermore, the rotational speed of the polishing tool 96 can be detected by a rotary encoder that detects the angle of the polishing tool 96 around the vertical axis AX5. Additionally, the rotational speed of the substrate W can be detected by a rotary encoder that detects the angle of the substrate W around the rotation axis AX3. The main control unit 134 can also control each component based on these detection results.

[0178] (7) In the above embodiments and modifications, the retaining rotation unit 35 holds the substrate W with the back side facing upward in a horizontal position. Furthermore, the rotating base 41 of the retaining rotation unit 35 is disposed below the substrate W. In this respect, the retaining rotation unit 35 can also be disposed upside down. That is, the rotating base 41 of the retaining rotation unit 35 is disposed above the substrate W. Additionally, the retaining rotation unit 35 holds the substrate W with the back side facing downward in a horizontal position. In this case, the polishing tool 96 contacts the substrate W with the back side facing downward from the lower side of the substrate W.

[0179] (8) In the above embodiments and variations, steps S21 to S26 are performed as a wet etching process. Figure 9 Alternatively, only steps S21 to S23 of the six steps S21 to S26 can be performed. Alternatively, only steps S24 to S26 of the six steps S21 to S26 can be performed. It should be noted that the wet etching process can be omitted if it is not required.

[0180] (9) In the above embodiments and variations, steps S31 to S36 were performed as the cleaning process for the substrate W. Figure 11 Alternatively, only steps S31 to S33 of the six steps S31 to S36 can be executed. Alternatively, only steps S34 to S36 of the six steps S31 to S36 can be executed.

[0181] Explanation of reference numerals in the attached figures

[0182] 1. Substrate processing apparatus

[0183] 9 Indexing Robot

[0184] CR substrate transport robot

[0185] 20 Inspection Units

[0186] Grinding Units 22 and 141

[0187] RV flip unit

[0188] 35. Maintain the rotating part

[0189] 37 Grinding Mechanism

[0190] 41 Rotating base

[0191] 43 Keep the pin

[0192] 45 Hot Plate

[0193] 47 Gas ejection outlet

[0194] 69 First cleaning fluid nozzle

[0195] 71 Second cleaning fluid nozzle

[0196] 73 Rinse Fluid Nozzle

[0197] 96 Grinding tools

[0198] 127 Laser Scanning Confocal Microscope

[0199] 130 Inspection and Control Department

[0200] 134 Main Control Unit

[0201] 143 Liquid treatment unit

[0202] 145 Second retaining rotating part

Claims

1. A substrate processing apparatus, comprising: Indexing robot, which moves the substrate in and out of the carrier; A grinding unit that grinds the back side of the substrate while heating it; A substrate transport robot transports the substrate from the indexing robot to the grinding unit. in, The grinding unit includes: a rotating holding unit that rotates the substrate while holding it in a horizontal position; a heating mechanism that heats the substrate; and a grinding tool that contacts the back side of the heated and rotating substrate to grind the back side of the substrate using a chemical mechanical grinding method. The rotating retaining part includes: A rotating base that can rotate about a rotation axis extending in the vertical direction; Three or more retaining pins are configured to be arranged in a ring shape on the upper surface of the rotating base in a manner surrounding the rotating shaft, and to retain the substrate separately from the upper surface of the rotating base by clamping the side of the substrate. and A gas outlet is provided, which opens on the upper surface of the rotating base, is located at the center of the rotating base, and ejects gas in such a way that gas flows from the center of the substrate to the periphery of the substrate in the gap between the substrate and the rotating base.

2. The substrate processing apparatus of claim 1, wherein It also has a control unit. During grinding, the control unit adjusts the grinding rate by controlling the heating temperature of the substrate based on the heating mechanism.

3. The substrate processing apparatus of claim 2, wherein The control unit further adjusts the grinding rate by controlling at least one of the contact pressure of the grinding tool on the substrate, the moving speed of the grinding tool, the rotational speed of the grinding tool, and the rotational speed of the substrate.

4. The substrate processing apparatus of claim 2, wherein It also includes an inspection unit for inspecting the substrate. The control unit enables the inspection unit to detect scratches formed on the back side of the substrate before grinding the back side of the substrate. The control unit causes the back side of the substrate to be polished when the scratch is detected by the inspection unit.

5. The substrate processing apparatus of claim 4, wherein The control unit enables the inspection unit to detect scratches formed on the back side of the substrate, and when a scratch is detected, to measure the depth of the scratch. The control unit causes the back side of the substrate to be ground until the thickness corresponding to the depth of the scratch measured by the inspection unit is removed.

6. The substrate processing apparatus according to any one of claims 1 to 5, wherein The grinding unit also includes a cleaning fluid nozzle for supplying cleaning fluid to the back side of the substrate held by the rotating holding part.

7. The substrate processing apparatus according to any one of claims 1 to 5, wherein It also includes a cleaning unit for cleaning the substrate. The cleaning unit includes: a second holding and rotating part that rotates the substrate while holding it in a horizontal position; and a second cleaning fluid nozzle that supplies cleaning fluid to the back side of the substrate held by the second holding and rotating part.

8. The substrate processing apparatus according to any one of claims 1 to 5, characterized in that, It also includes a flipping unit for flipping the substrate. The retaining rotation unit retains the substrate that has been flipped by the flipping unit with the back side of the substrate facing upwards.

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