JP3592233B2 - Substrate surface treatment apparatus and substrate surface treatment method - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
According to the present invention, a vapor containing an acid such as hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid (including HF and anhydrous HF), and acetic acid is guided to the surface of a substrate, and a film on the surface of the substrate is removed by a so-called gas phase etching process. The present invention relates to a substrate surface treatment apparatus and a substrate surface treatment method for performing the same. Substrates to be processed include various substrates such as semiconductor wafers, glass substrates for liquid crystal displays and plasma displays, and substrates for optical, magnetic and magneto-optical disks. The material of the substrate includes materials such as silicon, glass, resin, and ceramic. The removal of the film on the substrate surface may be for the purpose of selectively removing a part or all of a predetermined film, or may be for the purpose of cleaning the substrate surface.
[0002]
[Prior art]
In a manufacturing process of a semiconductor memory, when a memory capacitor film is formed on a semiconductor wafer (hereinafter, referred to as “wafer”), BSG (Boron-Silicate Glass), PSG (Phosphor-Silicate Glass), and BPSG (Boron-doped). An oxide film containing many impurities such as Phosphor-Silicate Glass is used as a sacrificial oxide film. These sacrificial oxide films can have a large selectivity with respect to a thermal oxide film or a CVD (chemical vapor deposition) oxide film in etching using hydrofluoric acid vapor, and the thermal oxide film or the CVD oxide film is used as an etching stopper film. And can be selectively removed.
[0003]
The etching selectivity in the etching process using hydrofluoric acid vapor depends on the temperature. For example, the etching rate of a thermal oxide film rapidly decreases with an increase in temperature, whereas the BPSG film maintains a relatively high etching rate irrespective of a temperature change. Therefore, when the BPSG film on the thermal oxide film formed on the surface of the wafer is selectively removed, the temperature of the semiconductor wafer is heated to 50 ° C. to 80 ° C., and a gas phase etching process using hydrofluoric acid vapor is performed.
[0004]
[Problems to be solved by the invention]
The etching process of an oxide film with hydrofluoric acid vapor is an extremely delicate process. In this process, the concentration of hydrofluoric acid vapor on the wafer surface is greatly involved. That is, if the concentration of the hydrofluoric acid vapor on the wafer surface is not uniform, it is not possible to perform a uniform etching process on the wafer surface.
[0005]
Conventionally, in order to perform this wafer etching process, the wafer is rotated in a horizontal plane while holding the wafer on a holding surface, and hydrofluoric acid vapor is supplied from the vapor supply means provided above the wafer toward the upper surface of the wafer. Further, the hydrofluoric acid vapor supplied to the wafer surface is exhausted through an exhaust port provided below the wafer. Here, the hydrofluoric acid vapor supplied to the upper surface of the wafer flows from the center of the wafer toward the peripheral edge due to the influence of the rotation of the wafer. Furthermore, the hydrofluoric acid vapor that has flowed out of the peripheral portion of the wafer due to the exhaust from the exhaust port flows downward at the exhaust port. Due to the influence of the hydrofluoric acid vapor flow, the concentration of the hydrofluoric acid vapor on the upper surface of the wafer is lower at the peripheral portion than at the center of the wafer surface. Therefore, the etching progress rate (etching rate) at the peripheral portion of the wafer surface is lower than that at the center portion of the wafer surface, and as a result, there is a problem that uniform etching cannot be performed in the wafer surface.
[0006]
Therefore, an object of the present invention is to solve the above-described technical problem, and to perform an etching process using a vapor containing an acid uniformly in a substrate surface, particularly, to prevent a decrease in an etching rate at a peripheral portion of the substrate. It is an object of the present invention to provide a substrate surface treatment apparatus and a substrate surface treatment method that can be used.
[0007]
Means for Solving the Problems and Effects of the Invention
According to a first aspect of the present invention, there is provided a substrate surface treatment apparatus for removing a film on a surface of a substrate by supplying a vapor containing an acid to the surface of the substrate. Substrate holding means for rotating the substrate about a rotation axis passing through the center of the substrate and perpendicular to the substrate, and a steam supply for supplying the acid-containing steam to the surface of the substrate held by the substrate holding means Means, and a peripheral member provided on the holding surface of the substrate holding means so as to surround the periphery of the substrate held by the substrate holding means.And an inner peripheral surface extending upward from the holding surface is formed on a side of the peripheral member that faces the substrate.A substrate surface treatment apparatus characterized in that:
[0008]
According to this configuration, the peripheral member is provided on the holding surface of the substrate holding means so as to surround the periphery of the substrate held on the holding surface.On the side of the peripheral member facing the substrate, an inner peripheral surface extending upward from the holding surface is formed.ing. Thus, the flow of the vapor outward from the center of the substrate due to the rotation of the substrate is temporarily blocked by the peripheral member. Therefore, a decrease in the concentration of the acid-containing vapor at the peripheral portion of the substrate can be prevented, and a decrease in the etching rate at the peripheral portion of the substrate can be prevented. Therefore, the concentration of the vapor containing the acid on the substrate surface becomes uniform, and a uniform etching process can be performed in the surface of the substrate surface.
[0009]
Here, "holding the substrate on the holding surface" means that the substrate is directly placed on the holding surface and held, or the substrate is separated from the holding surface by a predetermined distance. It may be held. The holding surface may be a flat surface along the substrate, or may be a gentle curved surface.
[0010]
Claims2The invention described inIn a substrate surface treatment apparatus that removes a film on the surface of a substrate by supplying a vapor containing an acid to the surface of the substrate, a rotation axis perpendicular to the substrate passes through the center of the substrate while holding the substrate on a holding surface. Holding means for rotating the substrate around the substrate, steam supply means for supplying steam containing acid to the surface of the substrate held by the substrate holding means, and the substrate holding means on the holding surface of the substrate holding means. A peripheral member provided to surround the periphery of the substrate held by theThe substrate surface treatment apparatus is characterized in that an inclined surface is formed on a side of the peripheral member, which is viewed from the substrate, so as to move away from the center of the substrate as the distance from the holding surface increases.
[0011]
According to this configuration, on the substrate side (inside) of the peripheral member, an inclined surface is formed so as to move away from the center of the substrate as the distance from the holding surface increases. Thereby, the vapor supplied to the outside of the substrate near the substrate peripheral portion can be guided toward the substrate, so that a decrease in the concentration of the acid-containing vapor at the substrate peripheral portion is further prevented, and the etching at the substrate peripheral portion is prevented. A decrease in the rate can be further prevented. Therefore, the concentration of the vapor containing the acid on the substrate surface becomes more uniform, and a more uniform etching process can be performed in the surface of the substrate surface.
[0012]
Claims3The invention described inIn a substrate surface treatment apparatus that removes a film on the surface of a substrate by supplying a vapor containing an acid to the surface of the substrate, a rotation axis perpendicular to the substrate passes through the center of the substrate while holding the substrate on a holding surface. Holding means for rotating the substrate around the substrate, steam supply means for supplying steam containing acid to the surface of the substrate held by the substrate holding means, and the substrate holding means on the holding surface of the substrate holding means. A peripheral member provided to surround the periphery of the substrate held by theThe substrate surface treatment apparatus is characterized in that a concave portion that is depressed in a direction away from the center of the substrate is formed on a side of the peripheral member that faces the substrate.
[0013]
According to this configuration, on the substrate side (inside) of the peripheral member, a concave portion that is depressed outward when viewed from the substrate is formed. Thereby, the flow of the vapor flowing outward from the center of the substrate due to the rotation of the substrate is temporarily and reliably blocked by the concave portion, so that the reduction in the concentration of the vapor containing acid at the peripheral portion of the substrate is further prevented, It is possible to further prevent a decrease in the etching rate at the periphery of the substrate. Therefore, the concentration of the vapor containing the acid on the substrate surface becomes more uniform, and a more uniform etching process can be performed in the surface of the substrate surface.
[0014]
According to a fourth aspect of the present invention, in the substrate surface treatment apparatus according to any one of the first to third aspects, the peripheral member is formed in an annular shape surrounding the periphery of the substrate without any gap. It is a substrate surface treatment apparatus characterized by the following.
[0015]
According to this configuration, the annular peripheral member is provided on the holding surface of the substrate holding means so as to surround the periphery of the substrate held on the holding surface without any gap. Thus, the flow of the vapor outward from the center of the substrate due to the rotation of the substrate is temporarily and reliably blocked by the annular peripheral member. For this reason, a decrease in the concentration of the acid-containing vapor at the periphery of the substrate can be further prevented, and a decrease in the etching rate at the periphery of the substrate can be further prevented. Therefore, the concentration of the vapor containing the acid on the substrate surface becomes more uniform, and a more uniform etching process can be performed in the surface of the substrate surface.
[0016]
According to a fifth aspect of the present invention, there is provided a substrate surface treatment method comprising removing a film on the surface of a substrate by using the substrate surface treatment apparatus according to any one of the first to fourth aspects. is there.
[0017]
According to the above-described method, a uniform etching process can be performed in the surface of the substrate surface, similarly to the effect of the invention of the substrate surface treatment apparatus according to any one of the above-described claims. A substrate with good uniformity can be provided.
[0018]
In addition, the same modification as that described above with respect to the invention of the substrate surface treatment apparatus according to any one of the first to fourth aspects can be made in the invention of the substrate surface treatment method.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
[0020]
FIG. 1 is an illustrative plan view for explaining the configuration of the substrate surface treatment apparatus according to the first embodiment of the present invention. This apparatus is an apparatus for removing an oxide film formed on the surface of a semiconductor wafer (hereinafter, simply referred to as “wafer”) W. More specifically, for example, when a sacrificial oxide film (BPSG film or the like) used for forming a memory capacitor is formed on a thermal oxide film formed on wafer W, this sacrificial oxide film is It is a device for selective removal. For this processing, in this substrate surface treatment apparatus, a film removing step is performed by supplying a vapor of hydrofluoric acid to the surface of the wafer W, thereby performing a gas phase etching process of hydrofluoric acid.
[0021]
A description will be given of the configuration of the apparatus. This apparatus includes a loader unit 10 on which a cassette CL containing a wafer W before processing is placed, and a vapor phase etching process for performing a vapor phase etching process using hydrofluoric acid vapor on the surface of the wafer W. A processing unit 40, a water-washing / drying processing unit 50 for rinsing the wafer W after the gas phase etching processing, and then performing a water-drying process, and a wafer W after being processed by the water-washing / drying processing unit 50. And an unloader unit 60 on which the cassette CU is placed.
[0022]
The loader unit 10 and the unloader unit 60 are arranged behind the front panel 77 of the substrate surface treating apparatus. The loader unit 10, the vapor phase etching unit 40, the washing / drying unit 50, and the unloader unit 60 are arranged in this order along a substantially U-shaped wafer transfer path 78 in plan view.
[0023]
A loader transfer robot that takes out unprocessed wafers W one by one from a cassette CL placed in the loader unit 10 and loads the wafer W into the vapor phase etching unit 40 between the loader unit 10 and the vapor phase etching processing unit 40. 71 are arranged. Further, between the vapor-phase etching processing section 40 and the washing / drying processing section 50, an intermediate transfer for taking out the wafer W after the vapor-phase etching processing from the vapor-phase etching processing section 40 and carrying the wafer W into the washing / drying processing section 50. A robot 81 is arranged. An unloader is provided between the rinsing / drying processing section 50 and the unloader section 60 to take out the wafer W after the rinsing / drying processing from the rinsing / drying processing section 50 and store the wafer W in the cassette CU placed in the unloader section 60. A transfer robot 72 is provided.
[0024]
Each of the loader transfer robot 71, the intermediate transfer robot 81, and the unloader transfer robot 72 has a form of a bending and stretching robot having a lower arm LA and an upper arm UA. The lower arm LA is rotated along a horizontal plane by a rotation drive mechanism (not shown). At the tip of the lower arm LA, an upper arm UA is provided so as to be freely rotatable along a horizontal plane. When the lower arm LA rotates, the upper arm UA rotates in a direction opposite to the rotation direction of the lower arm LA by twice the rotation angle of the lower arm LA. As a result, the lower arm LA and the upper arm UA can assume a contracted state in which both arms are vertically overlapped, and an extended state in which both arms are deployed toward one side or the other side along the path 78. it can.
[0025]
In this way, the loader transfer robot 71, the intermediate transfer robot 81, and the unloader transfer robot 72 can transfer the wafer W along the path 78 between the processing units or between the cassette and the processing unit.
[0026]
The rinsing / drying processing unit 50 for rinsing and drying the wafer W after the vapor phase etching process includes, for example, a spin chuck that holds the wafer W horizontally and rotates the wafer W, and a pure water cleaning unit 50 that holds the wafer W held by the spin chuck. A pure water supply nozzle for supplying water is provided. With this configuration, pure water is supplied to the front surface and / or the back surface of the wafer W to wash the front surface of the wafer W with water. After the completion of the water washing, the supply of pure water is stopped, and the spin chuck is rotated at a high speed to shake off and dry the surface of the wafer W.
[0027]
FIG. 2 is a schematic cross-sectional view for explaining the configuration of the vapor-phase etching processing section 40. The gas phase etching processing section 40 includes a hydrofluoric acid vapor generation container 43 in a housing 41 for storing a hydrofluoric acid aqueous solution 42 as an example of an aqueous solution containing an acid in a sealed state. At the bottom of the hydrofluoric acid vapor generation container 43, a disk-shaped punching plate 44 having a large number of through holes 44a is provided. The hydrofluoric acid vapor is supplied to the upper surface of the wafer W through a plurality of through holes 44 a formed in the punching plate 44.
[0028]
Below the punching plate 44, a hot plate 45 that horizontally holds the wafer W to be processed in a state of facing the punching plate 44 is arranged. Inside the hot plate 45, a heater 45b for heating the wafer W at a predetermined temperature (for example, 40 ° C. to 80 ° C.) is provided. Further, the hot plate 45 is fixed to an upper end of a rotating shaft 47 that is rotated (rotated) around a vertical axis OW (hereinafter, referred to as a rotating axis OW) passing through the center of the wafer W by a rotation driving mechanism 46 including a motor and the like. I have. An annular ring member R surrounding the wafer W is attached to the upper surface 45a of the hot plate 45, and details thereof will be described later.
[0029]
A bellows 48 that contracts up and down with respect to the bottom surface 41 a of the housing 41 is provided on the outer side of the hot plate 45 in plan view. The bellows 48 makes an annular contact portion 48 a provided at an upper end edge thereof come into contact with the periphery of the punching plate 44 (the lower surface of the hydrofluoric acid vapor generation container 43) to seal the space around the hot plate 45. A closed position (a position shown by a solid line in the figure) to form a processing chamber 85, and a retracted position (a position shown by a two-dot chain line in FIG. 2) in which the upper end edge is retracted below the upper surface 45a of the hot plate 45. In between, the drive mechanism is driven to extend / contract by a drive mechanism (not shown).
[0030]
The internal space of the bellows 48 is evacuated by an exhaust source 55 via an exhaust pipe 49 connected to an exhaust port 49a opened on the bottom surface 41a of the housing 41. The exhaust port 49a is located above the wafer W held on the hot plate 45, so that the hydrofluoric acid vapor supplied from above the wafer W can be exhausted smoothly. Note that the exhaust source 55 may be a forced exhaust mechanism such as an exhaust blower or an ejector, or may be an exhaust facility provided in a clean room where the substrate surface treatment apparatus is installed.
[0031]
On the side of the hot plate 45, a loading opening 21 for loading the wafer W and a loading opening 22 for discharging the wafer W are formed in the side wall of the housing 41. Shutters 38 and 39 are arranged in these openings 21 and 22, respectively. When the wafer W is loaded, the bellows 48 is lowered to the retracted position (the position indicated by the broken line in FIG. 2), the shutter 38 is opened, and the wafer W is received on the hot plate 45 by the loader transfer robot 71 (see FIG. 1). Passed. When the wafer W is carried out, the bellows 48 is set to the retreat position, the shutter 39 is opened, and the wafer W on the hot plate 45 is transferred to the intermediate transfer robot 81 and carried out. Note that the arrangement relationship between the opening 21 and the shutter 38 and the opening 22 and the shutter 39 is actually such that two line segments connecting these and the center of the wafer W are orthogonal to each other in plan view. In FIG. 2, for simplicity of illustration, these arrangement relations are such that two line segments connecting these and the center of the wafer W in a plan view overlap on a straight line (at the center of the wafer W). In contrast, the position is almost point-symmetrical.
[0032]
A nitrogen gas supply pipe 54 for supplying nitrogen gas as a carrier gas is connected to the space 35 above the level of the hydrofluoric acid aqueous solution 42 in the hydrofluoric acid vapor generating container 43. The space 35 can be connected via a valve 37 to a hydrofluoric acid vapor supply passage 36 for guiding hydrofluoric acid vapor to the punching plate 44. Nitrogen gas from a nitrogen gas supply source 31 is supplied to the hydrofluoric acid vapor supply path 36 via a flow rate controller (MFC) 32, a valve 33, and a nitrogen gas supply pipe 34. The nitrogen gas from the nitrogen gas supply source 31 is supplied to a nitrogen gas supply pipe 54 via a flow rate controller 52 and a valve 53. The valves 33 and 53 for switching the supply / stop of the nitrogen gas and the flow controllers 32 and 52 for changing the supply amount of the nitrogen gas are controlled by the controller 80.
[0033]
Further, the hydrofluoric acid aqueous solution 42 stored in the hydrofluoric acid vapor generating container 43 has a concentration (for example, about 39.6% at 1 atm and room temperature (20 ° C.)) at which a so-called pseudo-cofluoric composition is obtained. Has been prepared. In the hydrofluoric acid aqueous solution 42 having the pseudo-cofluoric composition, the evaporation rates of water and hydrogen fluoride are equal, so that hydrofluoric acid vapor is led from the valve 37 to the punching plate 44 via the hydrofluoric acid vapor supply passage 36. Even if the amount of the hydrofluoric acid aqueous solution 42 in the hydrofluoric acid vapor generation container 43 decreases, the concentration of the hydrofluoric acid vapor guided to the hydrofluoric acid vapor supply passage 36 is kept unchanged. In FIG. 2, reference numeral 90 denotes a temperature control pipe through which temperature control water for maintaining the hydrofluoric acid aqueous solution 42 in the hydrofluoric acid vapor generation container 43 at a constant temperature flows.
[0034]
Here, the configuration around the hydrofluoric acid vapor generation container 43 will be described in more detail. Above the wafer W, there is formed a container 91 having an internal space into which hydrofluoric acid vapor from the hydrofluoric acid vapor supply passage 36 and nitrogen gas as a carrier gas are introduced. Is provided so as to close the opening 91b on the bottom surface. The inner space of the container 91 is a cylindrical space having the rotation axis OW of the wafer W as a central axis. Further, a discharge port 36 a communicating with the hydrofluoric acid vapor supply passage 36 is opened in the inner peripheral surface 91 a of the container 91.
[0035]
In addition, a large number of through holes 44a are arranged at regular intervals (for example, at 10 mm intervals) in a grid pattern on almost the entire surface of the punching plate 44. In addition, the arrangement of the plurality of through holes 44a may be radially arranged at equal angular intervals. In addition, they may not necessarily be arranged at equal intervals, and for example, the intervals may be increased toward the periphery.
[0036]
As described above, the BPSG film and the thermal oxide film have significantly different etching rates due to hydrofluoric acid vapor at a certain temperature (for example, a predetermined temperature in the range of 40 ° C. to 80 ° C.). Thus, the BPSG on the surface of the wafer W can be selectively removed. Therefore, the hot plate 45 is energized to the internal heater 45b so as to maintain the wafer W at the above-mentioned constant temperature.
[0037]
Here, the annular ring member R provided on the hot plate 45 will be described in detail with reference to FIG. The ring member R is attached with a bolt or the like so as to be in close contact with the upper surface 45a of the hot plate 45, and is composed of a rotating body having a cross section S about the vertical axis OW. That is, the ring member R is formed in an annular shape that entirely surrounds the periphery of the wafer W without gaps. On the side of the ring member R looking into the wafer W, there is formed a tapered surface R1 composed of a planar inclined surface that moves away from the center of the wafer W as the distance from the upper surface 45a increases. The tapered surface R1 is an inner surface of a truncated cone with the vertical axis OW as a center. Below the tapered surface R1, there is formed a depression R2 that is depressed in a direction away from the center of the wafer W. The recess R2 is a space between the curved surface of the ring member R and the upper surface 45a.
[0038]
Here, the processing operation of the wafer W in the processing chamber 85 will be described. When performing the film removing step of removing the film on the surface of the wafer W, the bellows 48 is raised to the close contact position (the position indicated by the solid line in FIG. 2) in close contact with the periphery of the punching plate 44, and the bellows 48 is closed around the hot plate 45. A processing chamber 85 is formed. In this state, the controller 80 holds the valves 33, 37, and 53 in the open state. Thereby, the hydrofluoric acid vapor generated in the space 35 in the hydrofluoric acid vapor generation container 43 is pushed out to the hydrofluoric acid vapor supply passage 36 through the valve 37 by the nitrogen gas from the nitrogen gas supply pipe 54. The hydrofluoric acid vapor is further discharged from the discharge port 36a into the container 91 by the nitrogen gas from the nitrogen gas supply pipe 34, and further formed on the punching plate 44 that closes the opening 91b on the bottom surface of the container 91. The wafer W is supplied to the surface of the wafer W through the through hole 44a. Then, on the surface of the wafer W, the hydrofluoric acid vapor reacts with the oxide film (silicon oxide) on the surface of the wafer W, thereby removing the oxide film.
[0039]
At this time, an annular ring member R is provided on the upper surface 45a of the hot plate 45 so as to surround the periphery of the wafer W without any gap, so that the flow of hydrofluoric acid vapor flowing outward from the center of the wafer W is reduced. , Will be temporarily blocked by the ring member R. Therefore, a decrease in the concentration of hydrofluoric acid vapor at the peripheral portion of the wafer W is prevented, and a decrease in the etching rate at the peripheral portion of the wafer W can be prevented.
[0040]
Further, since the tapered surface R1 is formed on the wafer W side (inside) of the ring member R, the vapor supplied above the tapered surface R1 located at a position close to the peripheral portion of the wafer W is directed toward the wafer W. Can lead. Furthermore, since the recessed part R2 is formed on the wafer W side (inside) of the ring member R, the flow of hydrofluoric acid vapor outward from the center of the wafer W is temporarily and reliably blocked. Therefore, with the configuration of the tapered surface R1 and the recessed portion R2, a decrease in the concentration of hydrofluoric acid vapor at the peripheral portion of the wafer W is further prevented, and a decrease in the etching rate at the peripheral portion of the wafer W is further prevented. it can.
[0041]
After performing the film removing step for a predetermined period of time as described above, the controller 80 closes the valves 37 and 53 to stop the film removing step. At the same time, the controller 80 keeps the valve 33 open and controls the flow rate controller 32 to increase the flow rate of the nitrogen gas flowing through the pipe 34 so that the nitrogen gas passes through the punching plate 44. The liquid is supplied to the surface of the wafer W through the hole 44a. As a result, water molecules and hydrofluoric acid molecules existing near the surface of the wafer W are replaced and removed, and are carried out of the processing chamber 85 by exhausting the processing chamber 85 through the exhaust pipe 49. When nitrogen gas as an inert gas is supplied to the surface of the wafer W immediately after the film removing step in this manner, water and hydrofluoric acid molecules near the surface of the wafer W are promptly removed, and gas phase is removed. The etching process stops immediately. Then, the supply of the nitrogen gas after the film removing step is continued for a predetermined time (for example, 10 seconds or more, preferably about 20 seconds), and then the controller 80 closes the valve 33 to supply the nitrogen gas. Stop.
[0042]
As mentioned above, although one Embodiment of this invention was described, this invention can be implemented in another form. For example, in the above-described embodiment, the ring member R is a single member formed in an annular shape that surrounds the periphery of the wafer W without any gap. However, if the ring member R is provided so as to surround the periphery of the wafer W, Anything is fine. For example, the ring member R may be composed of a plurality of members in the circumferential direction, and a gap may be provided between the plurality of members. Further, in the ring member R of the above-described embodiment, a groove or a hole penetrating right and left of the cross section S in FIG. 3 may be further formed. However, in order to effectively prevent a decrease in the etching rate at the peripheral portion of the wafer W, it is preferable to adopt the above-described embodiment.
[0043]
Further, in the above-described embodiment, the tapered surface R1 and the recessed portion R2 are formed on the side of the ring member R looking into the substrate, but only the tapered surface R1 may be formed as shown in FIG. However, only the depression R2 may be formed as shown in FIG. Alternatively, neither the tapered surface R1 nor the depression R2 may be formed, and only the vertical surface V may be formed on the upper surface 45a of the hot plate 45 as shown in FIG.
[0044]
Furthermore, in the above-described embodiment, the tapered surface R1 is a flat inclined surface, but is not limited thereto, and may be a curved inclined surface as shown in FIG. Further, in the above-described embodiment, the depression R2 is a space interposed between the curved surface and the plane, but as shown in FIG. 5, even if the depression R2 is a space interposed between the plane and the plane. Good.
[0045]
In the above-described embodiment, the wafer W is directly placed and held on the planar upper surface 45a. However, the wafer W is held at a predetermined distance from the upper surface 45a by a plurality of pins or the like. May be. Further, in the above embodiment, the upper surface 45a is a flat surface along the lower surface of the wafer W, but may be a gentle curved surface.
[0046]
Further, in the above-described embodiment, the heater 45b is provided on the hot plate 45 as the substrate holding means. However, it is not necessary to particularly provide the heater 45b. For example, a flat plate on which a plurality of suction holes are arranged is provided. The wafer W may be rotated while suction-holding it.
[0047]
Further, in the above-described embodiment, the punching plate 44 as the vapor diffusion plate is provided in the opening 91b on the bottom surface of the cylindrical container 91, but may not be provided. However, in order to supply the vapor to the wafer W more uniformly, it is better to provide the punching plate 44.
[0048]
In the above-described embodiment, the center axis of the container 91 coincides with the rotation axis OW of the wafer W. However, the present invention is not limited to this, and the center axis of the container 91 is shifted from the rotation axis OW of the wafer W. Is also good. That is, the central axis of the container 91 and the rotation axis OW of the wafer W may be in a parallel relationship with a predetermined distance.
[0049]
In the above-described embodiment, hydrofluoric acid vapor is used as the vapor for etching the substrate surface. However, hydrofluoric acid vapor such as hydrochloric acid, nitric acid, sulfuric acid, hydrofluoric acid (including HF and anhydrous HF), and acetic acid are used. Any vapor containing an acid may be used. For example, it may be the vapor of an aqueous solution containing the above-mentioned acid, or a mixture of the above-mentioned acid-containing gas (in a gas phase) in steam.
[0050]
Further, in the above-described embodiment, an example in which nitrogen gas is used as the inert gas has been described, but another inert gas such as argon may be used.
[0051]
In addition, various design changes can be made within the scope of the matters described in the claims.
[0052]
【The invention's effect】
As described above in detail, according to the substrate surface treatment apparatus of the present invention, a decrease in the concentration of the vapor containing acid at the periphery of the substrate is prevented, and a decrease in the etching rate at the periphery of the substrate is prevented. Therefore, the concentration of the vapor containing the acid on the substrate surface becomes uniform, so that an effect of performing a uniform etching treatment on the surface of the substrate surface can be obtained.
[0053]
Further, according to the substrate surface treatment apparatus of the second aspect, the effect of the first aspect can be further improved.
[0054]
According to the substrate surface treatment apparatus of the invention according to claim 3,In oneThe effects of the described invention can be further improved.
[0055]
Further, according to the substrate surface treatment apparatus of the invention according to claim 4, the effect of the invention according to any one of claims 1 to 3 can be further improved.
[0056]
Further, according to the substrate surface treatment method of the invention according to claim 5, it is possible to provide a substrate surface treatment method having the same effect as that of the substrate surface treatment apparatus according to any one of claims 1 to 4.
[Brief description of the drawings]
FIG. 1 is an illustrative plan view for describing a configuration of a substrate surface treatment apparatus according to an embodiment of the present invention.
FIG. 2 is an illustrative sectional view for explaining a configuration of a vapor phase etching processing unit according to one embodiment of the present invention.
FIG. 3 is an illustrative sectional view showing, in an enlarged manner, a configuration around a ring member according to an embodiment of the present invention.
FIG. 4 is an illustrative sectional view showing a modification of the ring member according to the embodiment of the present invention.
FIG. 5 is an illustrative sectional view showing a modification of the ring member according to the embodiment of the present invention.
FIG. 6 is an illustrative sectional view showing a modification of the ring member according to the embodiment of the present invention.
[Explanation of symbols]
21 Loading opening
22 Carrying opening
31 Nitrogen gas supply source
32 Flow controller
33 valve
34 Nitrogen gas supply piping
35 space
36 Hydrofluoric acid vapor supply path
36a Discharge port
37 valve
38, 39 shutter
40 Vapor phase etching unit (substrate surface processing unit)
41 Housing
41a Bottom of housing
42 Hydrofluoric acid aqueous solution
43 Hydrofluoric acid vapor generation container
44 Punching plate
44a Through hole
45 Hot plate (substrate holding means)
45a Top surface of hot plate (holding surface)
45b heater
46 Rotation drive mechanism
47 Rotation axis
48 Bellows
49 Exhaust piping
49a Exhaust port
52 Flow controller
53 valve
54 Nitrogen gas supply piping
55 Exhaust source
80 Controller
85 Processing room
90 Temperature control piping
91 container (steam supply means)
91a Inner circumference
91b opening
OW rotation axis (substrate rotation axis)
R ring member (peripheral member)
R1 tapered surface (inclined surface)
R2 recess (recess)
Cross section of S ring member
V vertical plane
W wafer (substrate)

Claims (5)

In a substrate surface treatment apparatus that removes a film on the surface of a substrate by supplying a vapor containing an acid to the surface of the substrate,
While holding the substrate on the holding surface, substrate holding means for rotating the substrate about a rotation axis perpendicular to the substrate through the center of the substrate,
Vapor supply means for supplying a vapor containing the acid to the surface of the substrate held by the substrate holding means,
A peripheral member provided on the holding surface of the substrate holding unit so as to surround a periphery of the substrate held by the substrate holding unit ;
The substrate surface treatment apparatus according to claim 1, wherein an inner peripheral surface extending upward from the holding surface is formed on a side of the peripheral member that faces the substrate. In a substrate surface treatment apparatus that removes a film on the surface of a substrate by supplying a vapor containing an acid to the surface of the substrate,
While holding the substrate on the holding surface, substrate holding means for rotating the substrate about a rotation axis perpendicular to the substrate through the center of the substrate,
Vapor supply means for supplying a vapor containing the acid to the surface of the substrate held by the substrate holding means,
A peripheral member provided on the holding surface of the substrate holding unit so as to surround a periphery of the substrate held by the substrate holding unit;
Above desire side in the substrate of the peripheral member, wherein the to that board surface treatment apparatus that inclined surface moves away from the center of the substrate is formed as the distance from the holding surface. In a substrate surface treatment apparatus that removes a film on the surface of a substrate by supplying a vapor containing an acid to the surface of the substrate,
While holding the substrate on the holding surface, substrate holding means for rotating the substrate about a rotation axis perpendicular to the substrate through the center of the substrate,
Vapor supply means for supplying a vapor containing the acid to the surface of the substrate held by the substrate holding means,
A peripheral member provided on the holding surface of the substrate holding unit so as to surround a periphery of the substrate held by the substrate holding unit;
On the side facing the substrate of the peripheral member, board surface treatment apparatus characterized in that the recess recessed in the direction away from the center of the substrate is formed. 4. The substrate surface treatment apparatus according to claim 1, wherein the peripheral member is formed in an annular shape surrounding the periphery of the substrate without any gap. A substrate surface treatment method, comprising: removing a film on the surface of a substrate using the substrate surface treatment device according to any one of claims 1 to 4.

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