JP6985987B2 - Board processing method and board processing equipment - Google Patents

Description

The present invention relates to a substrate processing method and a substrate processing apparatus.

Conventionally, in the manufacturing process of a semiconductor substrate (hereinafter, simply referred to as “substrate”), various treatments are performed on the surface of the substrate. For example, in Patent Document 1, while supplying a chemical solution for etching to the vicinity of the peripheral edge of the upper surface of a rotating substrate, pure water, which is an etching inhibitor, is supplied to the vicinity of the peripheral edge of the lower surface of the substrate. A part of the pure water wraps around the upper surface of the substrate beyond the edge of the substrate due to surface tension and collides with the chemical solution. As a result, the chemical solution is diluted at the site where the pure water and the chemical solution collide, and the etching rate can be lowered at the site.

Japanese Unexamined Patent Publication No. 2016-139743

By the way, in the method of Patent Document 1, since the etching rate is only lowered by diluting the chemical solution with pure water in the peripheral portion of the upper surface, there is a possibility that the peripheral portion is etched more than expected. If the peripheral portion is etched, there is a possibility that a problem may occur in the transfer of the substrate in the subsequent process. Therefore, there is a demand for a new method capable of appropriately etching a processing region located inside the peripheral portion while protecting the peripheral portion.

The present invention has been made in view of the above problems, and an object of the present invention is to appropriately etch a processed region while protecting a peripheral portion.

The invention according to claim 1 is a substrate processing method, in which a) an oxidizing liquid that oxidizes one main surface of the substrate while rotating the disk-shaped substrate in a horizontal state is directed toward the substrate. The step of supplying the oxide liquid to the peripheral edge of the one main surface by discharging from the nozzle, and b) the etching solution for etching the one main surface while rotating the substrate in a horizontal state. The present invention comprises a step of supplying the etching solution to a processing region located inside the peripheral edge portion on the one main surface by discharging the etching solution from the nozzle toward the central portion of the one main surface.
The invention according to claim 2 is the substrate processing method according to claim 1, wherein by performing the steps a) and b), the oxidized liquid and the said oxide are formed on the peripheral portion of the main surface of the one. It is mixed with the etching solution.

The invention according to claim 3 is the substrate processing method according to claim 1 or 2 , wherein in the step a), the nozzle located on the other main surface side of the substrate is transferred to the other main surface. The oxidizing liquid is discharged toward the surface, and the oxidizing liquid is supplied to the peripheral edge portion of the one main surface via the outer peripheral end surface of the rotating substrate.

The invention according to claim 4 is the substrate processing method according to claim 3 , wherein in the step a), the nozzle located on the other main surface side is directed toward the central portion of the other main surface. The oxide liquid is discharged.

The invention of claim 5 is a substrate processing method according to claim 3 or 4, wherein a) and b) are carried out simultaneously.

The invention according to claim 6 is the substrate processing method according to claim 5 , wherein the etching solution discharged to the one main surface and the oxidizing solution discharged to the other main surface. Both are heated.

Invention of claim 7, a substrate processing method according to claim 5 or 6, the radius of the substrate is 150 mm, the rotational speed of the substrate in the a) and b) is 50 It is 300 rpm.

The invention according to claim 8 is the substrate processing method according to any one of claims 1 to 7 , wherein a plurality of first material films formed of the first material and the first material are used. A laminated film including a plurality of second material films formed of different second materials is provided in the processing region on the one main surface of the substrate, and is provided in the thickness direction before the step b). The pores extending to the above are formed in the laminated film, and in the step b), the plurality of second material films contained in the laminated film are selectively etched through the pores.

The invention according to claim 9 is the substrate processing method according to any one of claims 1 to 8 , wherein the etching solution is alkaline.

The invention according to claim 10 is a substrate processing apparatus, in which a substrate holding portion for holding a disk-shaped substrate in a horizontal state and a substrate rotating portion for rotating the substrate holding portion about a central axis facing in the vertical direction are used. An oxide liquid supply unit that supplies the oxide liquid to the peripheral portion of the one main surface by discharging the mechanism and the oxide liquid that oxidizes one main surface of the substrate from a nozzle toward the rotating substrate. And, by ejecting the etching solution for etching the one main surface from the nozzle toward the central portion of the one main surface of the rotating substrate, the etching solution is located inside the peripheral portion on the one main surface. An etching solution supply unit for supplying the etching solution is provided in the processing area to be processed.
The invention according to claim 11 is the substrate processing apparatus according to claim 10, wherein the oxide liquid discharged from the nozzle of the oxide liquid supply unit and the oxide liquid at the peripheral portion of the main surface of the one. The etching solution discharged from the nozzle of the etching solution supply unit is mixed.

According to the present invention, it is possible to appropriately etch a treated region on one main surface of a substrate while protecting the peripheral portion with an oxidizing liquid.

It is a figure which shows the structure of the substrate processing apparatus. It is a figure which shows the vicinity of the peripheral edge part of a substrate. It is a figure which shows the flow of processing a substrate. It is a figure for demonstrating the processing of a substrate. It is a figure for demonstrating the processing of a substrate. It is a figure which shows another example of a substrate. It is a figure for demonstrating the processing of a substrate. It is a figure for demonstrating the processing of a substrate. It is a figure which shows the other example of the substrate processing apparatus.

FIG. 1 is a diagram showing a configuration of a substrate processing apparatus 1 according to an embodiment of the present invention. The substrate processing device 1 is a single-wafer processing device that processes disk-shaped substrates 9 one by one. The substrate processing device 1 includes a substrate holding unit 21, a substrate rotation mechanism 22, a cup 23, an etching solution supply unit 3, and an oxide liquid supply unit 4.

The substrate holding portion 21 has a disk-shaped base portion 211 centered on a central axis J1 facing in the vertical direction. A plurality of chuck pins 212 are provided on the upper surface of the base portion 211. The plurality of chuck pins 212 are arranged at equal intervals in the circumferential direction on the circumference centered on the central axis J1. When the board holding portion 21 holds the board 9, a plurality of chuck pins 212 are pressed against the outer peripheral edge of the board 9. As a result, the substrate 9 is held in a horizontal state above the base portion 211. The center of the substrate 9 held by the substrate holding portion 21 is located on the central axis J1. The upper surface of the base portion 211 is parallel to the main surface 92 (hereinafter referred to as “lower surface 92”) facing downward of the substrate 9, and both face each other with a gap.

One end of the shaft portion 221 centered on the central axis J1 is fixed to the center of the lower surface of the base portion 211. The substrate rotation mechanism 22 having a motor rotates the other end of the shaft portion 221 so that the substrate holding portion 21 rotates with the substrate 9 about the central axis J1. The cup 23 has a substantially cylindrical shape that surrounds the base portion 211. In the treatment of the substrate 9, which will be described later, various treatment liquids scattered from the outer peripheral edge of the rotating substrate 9 are received by the inner peripheral surface of the cup 23 and recovered. In the substrate processing device 1, the upper portion of the cup 23 can be raised and lowered in the vertical direction by a cup raising and lowering mechanism (not shown). When the substrate 9 is carried in and out of the substrate processing device 1, the upper portion of the cup 23 is lowered to prevent the cup 23 from interfering with the external transport mechanism.

The oxidant liquid supply unit 4 includes a lower nozzle 41 and an oxidative liquid supply source 42. The lower nozzle 41 extends in the vertical direction. The base portion 211 and the shaft portion 221 are provided with a hollow portion extending in the vertical direction on the central axis J1, and the lower nozzle 41 is arranged in the hollow portion. The upper end surface of the lower nozzle 41 is arranged near the upper surface of the base portion 211. The lower nozzle 41 is located on the lower surface 92 side of the substrate 9 held by the substrate holding portion 21. The upper end surface of the lower nozzle 41 directly faces the lower surface 92 of the substrate 9. An oxide liquid supply source 42 is connected to the lower end of the lower nozzle 41 via a valve, and the oxide liquid is supplied from the oxide liquid supply source 42 to the lower nozzle 41. The oxidizing liquid is discharged upward from a discharge port provided in the center of the upper end surface of the lower nozzle 41. That is, the oxidizing liquid is discharged from the lower nozzle 41 toward the central portion of the lower surface 92 of the substrate 9. The details of the oxidizing liquid will be described later.

A chemical solution supply source 43 and a rinse solution supply source 44 are further connected to the lower nozzle 41 via a valve. By supplying the chemical solution from the chemical solution supply source 43 to the lower nozzle 41, the chemical solution is discharged from the lower nozzle 41 toward the central portion of the lower surface 92 of the substrate 9. By supplying the rinse liquid from the rinse liquid supply source 44 to the lower nozzle 41, the rinse liquid is discharged from the lower nozzle 41 toward the central portion of the lower surface 92. In the substrate processing device 1, the lower nozzle 41 and the chemical supply source 43 form a lower surface chemical supply unit, and the lower nozzle 41 and the rinse liquid supply source 44 form a lower surface rinse liquid supply unit. The lower nozzle 41 is shared by the oxide liquid supply unit 4, the lower surface chemical solution supply unit, and the lower surface rinse liquid supply unit. One or both of the lower surface chemical solution supply unit and the lower surface rinse liquid supply unit may have a nozzle separate from the lower nozzle 41.

The etching liquid supply unit 3 includes an upper nozzle 31 and an etching liquid supply source 32. The upper nozzle 31 extends in the vertical direction. The upper nozzle 31 is located on the main surface 91 (hereinafter referred to as “upper surface 91”) side facing upward of the substrate 9. Specifically, the upper nozzle 31 is arranged above the central portion of the upper surface 91. The lower end surface of the upper nozzle 31 directly faces the upper surface 91. An etching solution supply source 32 is connected to the upper end of the upper nozzle 31 via a valve, and the etching solution is supplied from the etching solution supply source 32 to the upper nozzle 31. The etching solution is discharged downward from a discharge port provided in the center of the lower end surface of the upper nozzle 31. That is, the etching solution is discharged from the upper nozzle 31 toward the central portion of the upper surface 91 of the substrate 9. The details of the etching solution will be described later.

A chemical solution supply source 33 and a rinse solution supply source 34 are further connected to the upper nozzle 31 via a valve. When the chemical solution is supplied from the chemical solution supply source 33 to the upper nozzle 31, the chemical solution is discharged from the upper nozzle 31 toward the central portion of the upper surface 91 of the substrate 9. By supplying the rinse liquid from the rinse liquid supply source 34 to the upper nozzle 31, the rinse liquid is discharged from the upper nozzle 31 toward the central portion of the upper surface 91. In the substrate processing apparatus 1, the upper nozzle 31 and the chemical solution supply source 33 form an upper surface chemical solution supply unit, and the upper nozzle 31 and the rinse liquid supply source 34 form an upper surface rinse liquid supply unit. The upper nozzle 31 is shared by the etching solution supply section 3, the upper surface chemical solution supply section, and the upper surface rinse solution supply section. One or both of the upper surface chemical solution supply unit and the upper surface rinse liquid supply unit may have a nozzle separate from the upper nozzle 31. Further, the chemical solution supply source 33 may also serve as the chemical liquid supply source 43, and the rinse liquid supply source 34 may also serve as the rinse liquid supply source 44.

The substrate processing apparatus 1 further includes an organic solvent supply unit 5. The organic solvent supply unit 5 includes an auxiliary nozzle 51 and an organic solvent supply source 52. The auxiliary nozzle 51 is arranged above the substrate 9. An organic solvent supply source 52 is connected to the auxiliary nozzle 51 via a valve. By supplying the organic solvent from the organic solvent supply source 52 to the auxiliary nozzle 51, the organic solvent is discharged from the auxiliary nozzle 51 toward the central portion of the upper surface 91 of the substrate 9. The substrate processing device 1 may be provided with a nozzle moving mechanism for moving each of the upper nozzle 31 and the auxiliary nozzle 51. The nozzle moving mechanism selectively arranges the upper nozzle 31 and the auxiliary nozzle 51 at a position facing the upper surface 91 of the substrate 9 and a standby position horizontally separated from the substrate 9. The nozzle moving mechanism may move the upper nozzle 31 and the auxiliary nozzle 51 individually.

FIG. 2 is a view showing the vicinity of the peripheral edge portion 93 of the substrate 9, and shows a cross section of the substrate 9 on the surface including the central axis J1. The substrate 9 includes a substrate main body 90 and a thin film 911. The thin film 911 is formed on the upper surface of the substrate body 90 with a predetermined material (for example, amorphous silicon) and covers the entire upper surface. The upper surface 91 of the substrate 9 is the surface of the thin film 911. The lower surface 92 of the substrate 9 is the lower surface of the substrate main body 90. A thin film may be formed on the lower surface 92. The thin film 911 is also provided on a part of the outer peripheral end surface 94 (so-called bevel surface) of the substrate 9. The peripheral portion 93 described above is an annular portion of the substrate 9 including the outer peripheral end surface 94 and its vicinity. In the container for accommodating the substrate 9, the substrate 9 is held in a state where the peripheral edge portion 93 of the substrate 9 is in contact with the holding portion of the container and the portion inside the peripheral edge portion 93 is not in contact with any member. ..

Here, the etching solution used in the substrate processing apparatus 1 is capable of etching the thin film 911, and is TMY (trimethyl-2 hydroxyethylammonium hydroxide), TMAH (tetramethylammonium hydroxide), and ammonia. An etching solution having alkalinity such as water (NH _{4 OH) is exemplified.} In this embodiment, an aqueous solution of TMY is used as the etching solution. An acidic etching solution may be used. Further, the oxidizing liquid used in the substrate processing apparatus 1 is capable of oxidizing the thin film 911 (that is, forming an oxide film), and includes hydrogen peroxide solution (H ₂ O ₂ ) and ammonia water. Examples thereof include a mixed solution of hydrogen peroxide solution and ozone water. In this embodiment, hydrogen peroxide solution is used as the oxidizing liquid.

FIG. 3 is a diagram showing a flow in which the substrate processing apparatus 1 processes the substrate 9. In the substrate processing apparatus 1 of FIG. 1, the substrate 9 to be processed is carried in in advance by an external transfer mechanism and held by the substrate holding unit 21. In the processing of the substrate 9, first, the rotation of the substrate 9 is started by the substrate rotation mechanism 22 (step S11). The substrate 9 rotates together with the substrate holding portion 21 in a horizontal state. Further, the chemical solution is supplied to the central portion of the upper surface 91 of the substrate 9 by the upper surface chemical solution supply unit via the upper nozzle 31 arranged at the opposite position, and the central portion of the lower surface 92 is supplied by the lower surface chemical solution supply unit via the lower nozzle 41. The chemical solution is supplied to (step S12).

On the upper surface 91 and the lower surface 92, the chemical solution spreads toward the outer peripheral edge of the substrate 9 due to the rotation of the substrate 9, and the chemical solution is supplied to the entire upper surface 91 and the lower surface 92. The chemical liquid scattered from the outer peripheral edge of the substrate 9 is received and recovered by the inner peripheral surface of the cup 23 (the same applies when the rinse liquid, the oxidizing liquid and the etching liquid described later are supplied). The chemical solution is, for example, DHF (dilute hydrofluoric acid), and the supply of the chemical solution removes the natural oxide films on the upper surface 91 and the lower surface 92. In the substrate processing apparatus 1, other types of chemicals may be used.

When the discharge of the chemical solution is continued for a predetermined time, the discharge of the chemical solution is stopped. Subsequently, the upper surface rinse liquid supply unit supplies the rinse liquid to the central portion of the upper surface 91 via the upper nozzle 31, and the lower surface rinse liquid supply unit supplies the rinse liquid to the central portion of the lower surface 92 via the lower nozzle 41. It is supplied (step S13). On the upper surface 91 and the lower surface 92, the rinsing liquid spreads toward the outer peripheral edge of the substrate 9 due to the rotation of the substrate 9, and the rinsing liquid is supplied to the entire upper surface 91 and the lower surface 92. The rinsing solution is, for example, pure water, and the supply of the rinsing solution removes the chemical solution adhering to the upper surface 91 and the lower surface 92. In the substrate processing apparatus 1, a rinsing liquid other than pure water may be used. Discharge of the rinse liquid is continued for a predetermined time, and then stopped.

Subsequently, the oxidizing liquid supply source 42 supplies the oxidizing liquid to the lower nozzle 41, so that the oxidizing liquid is continuously discharged from the lower nozzle 41 toward the central portion of the lower surface 92 (step S14). Further, when the etching liquid supply source 32 supplies the etching liquid to the upper nozzle 31, the etching liquid is continuously discharged from the upper nozzle 31 toward the central portion of the upper surface 91 (step S15). In this processing example, the ejection of the oxidizing liquid from the lower nozzle 41 and the ejection of the etching liquid from the upper nozzle 31 are started almost at the same time.

At this time, on the lower surface 92, the oxidizing liquid spreads toward the outer peripheral edge of the substrate 9 due to the rotation of the substrate 9, and the oxidizing liquid is supplied to the entire lower surface 92. The substrate body 90 is formed of non-oxide (for example, silicon), and a uniform oxide film is formed on the entire lower surface 92 by an oxidation reaction with an oxidizing liquid. At the outer peripheral edge, a part of the oxidizing liquid is scattered. The other part of the oxidizing liquid adheres to the outer peripheral end surface 94 due to surface tension and reaches the peripheral edge portion 93 of the upper surface 91. In other words, the oxidizing liquid discharged from the lower nozzle 41 toward the lower surface 92 is supplied to the peripheral edge portion 93 of the upper surface 91 via the outer peripheral end surface 94.

On the upper surface 91, the etching solution spreads toward the outer peripheral edge of the substrate 9 due to the rotation of the substrate 9. As described above, the oxidizing liquid is present on the peripheral portion 93 of the upper surface 91. Therefore, as shown in FIG. 4, the etching solution 81 and the oxidizing solution 82 are mixed at the peripheral edge portion 93 of the upper surface 91. FIG. 4 schematically shows the etching solution 81 and the oxidizing solution 82 in the vicinity of the peripheral edge portion 93, and a reference numeral 83 is attached to a portion where the etching solution 81 and the oxidizing solution 82 are mixed. At the peripheral portion 93 of the upper surface 91, the etching of the substrate 9 (here, the etching of the thin film 911) is suppressed by mixing the oxidizing liquid 82 with the etching liquid 81. The reason why the etching of the substrate 9 is suppressed by the mixing of the etching solution 81 and the oxidizing solution 82 is not clear, but the upper surface 91 is microscopically oxidized by the oxidizing solution 82 (a oxide film is microscopically formed). It is considered that this is because it is protected from the etching solution 81. When a hydrogen peroxide solution is used as the oxidizing solution 82, the concentration of hydrogen peroxide in the oxidizing solution 82 is, for example, 8% by weight or more, preferably 15% by weight, in order to more reliably suppress the etching in the peripheral portion 93. % Or more.

On the other hand, the thin film 911 is etched by the etching solution 81 in the region 95 (hereinafter referred to as “processed region 95”) inside the peripheral edge portion 93 on the upper surface 91. FIG. 5 shows the substrate 9 on which the thin film 911 is etched in the processing region 95, and the etching solution 81 and the oxidizing solution 82 are not shown. In the substrate processing apparatus 1, the oxidizing liquid 82 discharged from the lower nozzle 41 toward the lower surface 92 while appropriately etching the processing region 95 with the etching liquid discharged from the upper nozzle 31 toward the processing region 95 on the upper surface 91. This makes it possible to protect the peripheral edge portion 93 of the upper surface 91 (sufficiently lower the etching rate or prevent etching). Actually, the outer peripheral end surface 94 (bevel surface) of the substrate 9 is also protected by the oxidizing liquid 82.

In the preferred substrate processing apparatus 1, the etching solution supply source 32 has a heater, and the etching solution 81 heated to a predetermined temperature (for example, 85 ° C.) is discharged to the upper surface 91. As a result, the thin film 911 is etched at a relatively high etching rate in the processing region 95. More preferably, the oxidizing liquid supply source 42 has a heater, and the oxidizing liquid 82 heated to a predetermined temperature (for example, 70 ° C.) is discharged to the lower surface 92. As a result, the high temperature state of the etching solution 81 can be easily maintained, and the etching rate of the processing region 95 can be further increased. The high-temperature oxidizing liquid 82 is produced, for example, by mixing high-temperature pure water and normal-temperature hydrogen peroxide. Similarly, the high-temperature etching solution 81 may be produced by mixing high-temperature pure water with room temperature TMY or the like.

The conditions for allowing the oxidizing liquid 82 discharged from the lower nozzle 41 toward the lower surface 92 to reach the peripheral edge portion 93 of the upper surface 91 are appropriately determined according to the radius of the substrate 9, the type of the oxidizing liquid 82, and the like. In one example, when the radius of the substrate 9 is 150 mm and the oxidizing liquid 82 is discharged from the lower nozzle 41 at a flow rate of 1 to 2 L / min, the rotation speed of the substrate 9 is set to, for example, 50 to 300 rpm. Ru. This makes it possible to appropriately bring the oxidizing liquid 82 to the peripheral edge portion 93 of the upper surface 91. In the substrate processing apparatus 1, the lower the rotation speed of the substrate 9, the width of the region of the upper surface 91 where the oxidizing liquid 82 reaches from the outer peripheral end surface 94 (the width in the radial direction from the outer peripheral end surface 94 toward the inside, and hereinafter, “mixing”. The average value of "width in the region") becomes large, and the variation of the width in the circumferential direction also becomes large. Therefore, from the viewpoint of reducing the variation in the width while ensuring a certain width (for example, 1 to 3 mm) in the mixed region, the rotation speed of the substrate 9 is preferably set to 100 to 200 rpm. More preferably, the rotation speed of the substrate 9 is 150 to 200 rpm.

When the discharge of the oxidizing liquid 82 and the etching liquid 81 is continued for a predetermined time, the discharge of both is stopped. Subsequently, the upper surface rinse liquid supply unit supplies the rinse liquid to the central portion of the upper surface 91 via the upper nozzle 31, and the lower surface rinse liquid supply unit supplies the rinse liquid to the central portion of the lower surface 92 via the lower nozzle 41. It is supplied (step S16). On the upper surface 91 and the lower surface 92, the rinsing liquid spreads toward the outer peripheral edge of the substrate 9 due to the rotation of the substrate 9, and the rinsing liquid is supplied to the entire upper surface 91 and the lower surface 92. By supplying the rinsing liquid, the etching liquid 81 adhering to the upper surface 91 and the oxidizing liquid 82 adhering to the lower surface 92 are removed. Discharge of the rinse liquid is continued for a predetermined time, and then stopped.

Subsequently, the organic solvent is supplied to the central portion of the upper surface 91 by the organic solvent supply unit 5 via the auxiliary nozzles 51 arranged at the facing positions (step S17). On the upper surface 91, the organic solvent spreads toward the outer peripheral edge of the substrate 9 due to the rotation of the substrate 9, and the organic solvent is supplied to the entire upper surface 91. The organic solvent is, for example, IPA (isopropyl alcohol), and the rinsing solution on the upper surface 91 is replaced with the organic solvent. In the substrate processing apparatus 1, an organic solvent other than IPA may be used. Discharge of the organic solvent is continued for a predetermined time and then stopped.

When the supply of the organic solvent is completed, the substrate rotation mechanism 22 causes the rotation speed of the substrate 9 to be higher than that at the time of supplying the treatment liquid (that is, the chemical liquid, the rinsing liquid, the oxidizing liquid, the etching liquid and the organic solvent), thereby making the substrate higher. The drying process (spin drying) of 9 is started (step S18). When the drying process is completed, the rotation of the substrate 9 is stopped (step S19). The substrate 9 is carried out from the substrate processing device 1 by an external transfer mechanism. As described above, the processing of the substrate 9 in the substrate processing apparatus 1 is completed.

In the above processing example, in order to simplify the explanation, a case where the thin film 911 is removed in the processing region 95 on the upper surface 91 of the substrate 9 and the thin film 911 is left in the peripheral portion 93 has been described. It may be used in various treatments against.

FIG. 6 is a diagram showing another example of the substrate. In the substrate 9a of FIG. 6, the laminated film 912 is formed inside the peripheral edge portion 93 on the upper surface of the substrate main body 90. That is, the laminated film 912 is provided in the processing region 95 on the upper surface 91. The laminated film 912 includes a plurality of first material films 913 formed of the first material and a plurality of second material films 914 formed of a second material different from the first material. The first material film 913 and the second material film 914 are alternately provided in the thickness direction (stacking direction). For example, the first material film 913 is an insulating film such as a silicon oxide film. The first material film 913 may be a film made of a material having a sufficiently low etching rate by an etching solution (a material that is hardly etched), and may be a silicon nitride film, TEOS (tetraethoxysilane), or the like. The second material film 914 is a polysilicon film. The second material film 914 may be a film of another material having a relatively high etching rate with the etching solution.

On the other hand, the laminated film 912 is not formed on the surface of the peripheral edge portion 93 on the upper surface of the substrate main body 90. The surface of the peripheral edge portion 93 of the upper surface 91 of the substrate 9a is the surface of the substrate main body 90. The substrate body 90 is formed of non-oxide (for example, silicon), and the etching rate of the substrate body 90 by the etching solution is relatively high. Further, the surface of the substrate body 90 can be oxidized by the oxidizing liquid. The peripheral edge portion 93 of the upper surface 91 may be a film surface of a material such as a second material film 914 that is etched by an etching solution and can be oxidized by an oxidizing solution. The lower surface 92 of the substrate 9a is the lower surface of the substrate main body 90. The lower surface 92 of the substrate 9a may be the surface of a thin film formed on the lower surface of the substrate body 90.

When the substrate processing apparatus 1 processes the substrate 9a, as shown in FIG. 7, a plurality of holes 915 extending in the thickness direction with respect to the laminated film 912 are formed in advance by an external device. Each hole 915 penetrates a plurality of first material films 913 and a plurality of second material films 914. The formation of the pores 915 is performed, for example, by reactive ion etching.

In the processing of the substrate 9a in the substrate processing apparatus 1, the chemical solution is supplied to the upper surface 91 and the lower surface 92 and the rinse solution is supplied to the upper surface 91 and the lower surface 92 in order while rotating the substrate 9a in the same manner as described above. (FIG. 3: Steps S11 to S13). Subsequently, the ejection of the oxidizing liquid from the lower nozzle 41 to the central portion of the lower surface 92 and the ejection of the etching liquid from the upper nozzle 31 to the central portion of the upper surface 91 are started substantially at the same time (steps S14 and S15).

On the lower surface 92, the oxidation liquid spreads toward the outer peripheral edge of the substrate 9a due to the rotation of the substrate 9a, and an oxide film is formed. Further, a part of the oxidizing liquid is supplied to the peripheral edge portion 93 of the upper surface 91 via the outer peripheral end surface 94 (see FIG. 4). On the upper surface 91, the etching solution spreads toward the outer peripheral edge of the substrate 9a due to the rotation of the substrate 9a. At the peripheral edge portion 93 of the upper surface 91, etching is suppressed by mixing the etching solution and the oxidizing solution.

In the processing region 95 of the upper surface 91, the second material film 914 is selectively etched by the etching liquid that has entered the hole 915. The first material film 913 is hardly etched by the etching solution. As a result, as shown in FIG. 8, the second material film 914 recedes from the inner peripheral surface of the pore portion 915. In other words, a structure in which the first material film 913 projects inward is obtained from the inner peripheral surface of the widened hole 915. If the oxide liquid adheres to the surface of the second material film 914 in the pore portion 915, the surface of the second material film 914 is oxidized, so that the oxide liquid is not limited to the peripheral portion 93 of the upper surface 91. It can be said that the treatment region 95 is also a treatment liquid that can be oxidized.

Discharge of the oxidizing liquid and the etching liquid is continued for a predetermined time, and then stopped. Subsequently, the rinse liquid is supplied to the upper surface 91 and the lower surface 92, and the organic solvent is supplied to the upper surface 91 in order (steps S16 and S17). After the substrate 9a is dried at high speed, the rotation of the substrate 9a is stopped (steps S18 and S19), and the processing of the substrate 9a in the substrate processing apparatus 1 is completed.

In the treatment of the substrate 9a on which the laminated film 912 is provided, it takes a long time to selectively etch the second material film 914 through the pores 915. Therefore, if the treatment is performed without supplying the oxidizing liquid, the etching amount at the peripheral edge portion 93 of the upper surface 91 becomes large (for example, the etching amount becomes several tens of μm with respect to the original thickness of 775 μm). , A problem occurs in the transfer of the substrate 9a in the subsequent process.

On the other hand, in the substrate processing apparatus 1, by protecting the peripheral edge portion 93 of the upper surface 91 with an oxidizing liquid, it is possible to prevent the peripheral edge portion 93 from being etched in the selective etching of the second material film 914 which requires a long time. can do. As a result, it is possible to prevent the above-mentioned problems from occurring. Since the thickness of the oxide film formed on the lower surface 92 of the substrate 9a and the peripheral edge portion 93 of the upper surface 91 is several nm, there is no problem in transporting the substrate 9a and it is necessary to remove it. No. In the above process, since the outer peripheral end surface 94 (bevel surface) of the substrate 9a is also protected by the oxidizing liquid, it is possible to prevent the diameter of the substrate 9a from becoming smaller.

FIG. 9 is a diagram showing another example of the substrate processing apparatus. In the substrate processing apparatus 1a of FIG. 9, the configuration of the oxide liquid supply unit 4a is different from that of the substrate processing apparatus 1 of FIG. Other configurations are the same as those of the substrate processing apparatus 1 of FIG. 1, and the same configurations are designated by the same reference numerals.

The oxide liquid supply unit 4a includes an oxide liquid nozzle 41a located on the upper surface 91 side of the substrate 9. The oxidant nozzle 41a extends in the vertical direction, and is supported so as to be inclined with respect to the vertical direction so that the lower end surface on which the discharge port is formed is located radially outside the upper end surface. .. Further, the discharge port of the oxide liquid nozzle 41a faces the vicinity of the peripheral edge portion 93 of the upper surface 91. The oxidant liquid is discharged from the oxidative liquid nozzle 41a toward the peripheral edge portion 93 of the upper surface 91. The discharge direction of the oxidative liquid in the oxidant liquid nozzle 41a is downward and outward in the radial direction.

In the substrate processing apparatus 1a, the discharge of the oxide liquid from the oxide liquid nozzle 41a to the peripheral portion 93 of the upper surface 91 and the discharge of the etching liquid from the upper nozzle 31 to the central portion of the upper surface 91 are started almost at the same time. In the processing region 95 of the upper surface 91, the thin film 911 (see FIG. 2) is etched by the etching solution. At the peripheral edge portion 93 of the upper surface 91, etching is suppressed by mixing the etching solution and the oxidizing solution. As described above, also in the substrate processing apparatus 1a, it is possible to appropriately etch the processing region 95 while protecting the peripheral edge portion 93 of the upper surface 91 with the oxidizing liquid. Of course, the substrate 9a of FIG. 6 may be processed in the substrate processing apparatus 1a of FIG.

As described above, in the processing of the substrates 9 and 9a in the substrate processing apparatus 1, 1a, the step of supplying the oxidizing liquid to the peripheral edge portion 93 of the upper surface 91 and the etching to the processing region 95 located inside the peripheral edge portion 93. The process of supplying the liquid is performed. As a result, it is possible to appropriately etch the processed region 95 on the upper surface 91 of the substrates 9 and 9a while protecting the peripheral portion 93 with the oxidizing liquid.

By the way, in the substrate processing apparatus 1a of FIG. 9, in the processing of the substrates 9, 9a, the processing region 95 of the upper surface 91 is caused by the liquid splashing of the oxide liquid discharged from the oxide nozzle 41a toward the peripheral edge portion 93 of the upper surface 91. Oxidation liquid may adhere to. In this case, when the surface of a part of the thin film 911 or the second material film 914 is oxidized, the surface (oxide film surface) is hardly etched by the etching solution. On the other hand, in the substrate processing apparatus 1 of FIG. 1, since the oxidizing liquid is discharged from the lower nozzle 41 located on the lower surface 92 side of the substrates 9 and 9a toward the lower surface 92, it is discharged toward the substrates 9 and 9a. It is possible to prevent the oxidizing liquid from adhering to the processing region 95 on the upper surface 91 due to the splashing of the oxidizing liquid.

In the substrate processing devices 1 and 1a, it is also possible to individually perform a step of supplying the oxidizing liquid to the peripheral edge portion 93 of the upper surface 91 and a step of supplying the etching solution to the processing region 95 located inside the peripheral edge portion 93. be. For example, in the substrate processing apparatus 1 of FIG. 1, the oxide liquid is discharged from the lower nozzle 41 toward the lower surface 92 while rotating the substrates 9, 9a. Further, in parallel with the discharge of the oxidizing liquid, pure water is discharged from the upper nozzle 31 toward the central portion of the upper surface 91. As a result, the oxide liquid reached through the outer peripheral end surface 94 forms an oxide film on the peripheral portion 93 of the upper surface 91, and the infiltration of the oxide liquid into the treatment region 95 by pure water is suppressed. After that, the etching solution is discharged from the upper nozzle 31 toward the central portion of the upper surface 91. This makes it possible to appropriately etch the processed region 95 on the upper surface 91 of the substrates 9 and 9a while protecting the peripheral edge portion 93 by using the oxide film formed by the oxidizing liquid. The same applies to the substrate processing apparatus 1a of FIG. Even when an oxide film is formed on the peripheral edge portion 93 of the upper surface 91 before the etching solution is supplied to the processing region 95, it can be considered that the peripheral edge portion 93 is substantially protected by the oxidizing solution. ..

On the other hand, when the step of supplying the oxidizing liquid to the peripheral edge portion 93 of the upper surface 91 and the step of supplying the etching solution to the processing region 95 located inside the peripheral edge portion 93 are simultaneously performed, the treatment of the substrates 9 and 9a is performed. It is possible to perform it efficiently (that is, shorten the time required for processing). Further, in this case as well, the infiltration of the oxidizing liquid into the treated region 95 can be suppressed by the etching liquid, and the treated region 95 can be appropriately etched.

Various modifications are possible in the substrate processing and substrate processing devices 1, 1a.

In the substrate processing apparatus 1 of FIG. 1, the oxide liquid is discharged from the upper nozzle 31 and the etching liquid is discharged from the lower nozzle 41, so that the peripheral portion 93 of the lower surface 92 is protected by the oxide liquid that wraps around from the upper surface 91 to the lower surface 92. On the other hand, the processing region (processed region on the lower surface 92) located inside the peripheral edge portion 93 may be etched. Similarly, in the substrate processing apparatus 1a of FIG. 9, the etching liquid may be discharged from the lower nozzle 41 while discharging the oxidizing liquid from the oxidizing liquid nozzle facing the peripheral edge portion 93 of the lower surface 92.

As described above, in the substrate processing devices 1, 1a, the oxidizing liquid that oxidizes the main surface of the substrates 9, 9a is discharged from the nozzle toward the substrates 9, 9a, whereby the peripheral edge of the main surface of the substrate 9, 9a is discharged. By the step of supplying the oxidizing liquid to the portion 93 and the etching liquid for etching the one main surface being discharged from the nozzle toward the substrates 9, 9a, the position is located inside the peripheral edge portion 93 on the one main surface. The step of supplying the etching solution to the processing area to be processed is performed. Thereby, on the one main surface of the substrates 9, 9a, the treated region can be appropriately etched while protecting the peripheral portion 93 with the oxidizing liquid.

In the substrate processing apparatus 1 of FIG. 1, the lower nozzle 41 may be arranged at a position facing the peripheral edge portion 93 of the lower surface 92 of the substrates 9, 9a. Also in this case, the oxidizing liquid can be supplied to the peripheral edge portion 93 of the upper surface 91 via the outer peripheral end faces 94 of the rotating substrates 9, 9a. From the viewpoint of making the entire lower surface 92 uniform (forming a uniform oxide film) when the lower surface 92 of the substrates 9, 9a is oxidized by the oxidizing liquid, the lower nozzle 41 is directed toward the central portion of the lower surface 92. It is preferable that the oxidizing liquid is discharged. When an oxide film is formed on the entire lower surface 92, the lower surface 92 can be protected by the oxide film in a subsequent step.

The etching solution does not necessarily have to be discharged toward the central portion of the upper surface 91, and the etching solution is directed from the upper nozzle 31 toward the position inside the peripheral portion 93 and outside the central portion on the upper surface 91. May be ejected. That is, the processing region where etching is performed does not necessarily have to include the central portion.

When none of the treatment liquids is discharged toward the central portion of the lower surface 92 of the substrates 9 and 9a, a substrate holding portion that adsorbs and holds the central portion of the lower surface 92 may be provided.

The substrate to be processed in the substrate processing devices 1 and 1a is not limited to the semiconductor substrate, and may be another substrate.

The above-described embodiments and configurations in the respective modifications may be appropriately combined as long as they do not conflict with each other.

1,1a Substrate processing device 3 Etching liquid supply part 4, 4a Oxidation liquid supply part 9, 9a Substrate 21 Board holding part 22 Board rotation mechanism 31 Upper nozzle 41 Lower nozzle 41a Oxidizing liquid nozzle 81 Etching liquid 82 Oxidizing liquid 91 (Substrate ) Top surface 92 (board) bottom surface 93 (board) peripheral edge 94 (board) outer peripheral end face 95 (board) processing area 912 Laminated film 913 First material film 914 Second material film 915 Hole J1 Central axis S11 ~ S19 step

Claims (11)

It is a board processing method
a) While rotating the disk-shaped substrate in a horizontal state, an oxidizing liquid that oxidizes one main surface of the substrate is discharged from a nozzle toward the substrate to reach the peripheral edge of the one main surface. The step of supplying the oxide liquid and
b) While rotating the substrate in a horizontal state, the etching solution for etching the one main surface is discharged from the nozzle toward the central portion of the one main surface, whereby the peripheral edge of the one main surface is discharged. The step of supplying the etching solution to the processing area located inside the portion, and
A substrate processing method comprising. The substrate processing method according to claim 1.
A substrate processing method characterized in that the oxidizing liquid and the etching liquid are mixed at the peripheral portion of the one main surface by performing the steps a) and b). The substrate processing method according to claim 1 or 2.
In the step a), the oxidizing liquid is discharged from the nozzle located on the other main surface side of the substrate toward the other main surface, and the oxidizing liquid is passed through the outer peripheral end surface of the rotating substrate. Is supplied to the peripheral portion of the one main surface. The substrate processing method according to claim 3.
A substrate processing method, characterized in that, in the step a), the oxidizing liquid is discharged from the nozzle located on the other main surface side toward the central portion of the other main surface. The substrate processing method according to claim 3 or 4.
The substrate processing method, wherein said a) and b) are carried out simultaneously. The substrate processing method according to claim 5.
A substrate processing method comprising heating both the etching solution discharged to the one main surface and the oxidizing solution discharged to the other main surface. The substrate processing method according to claim 5 or 6.
The radius of the substrate is 150 mm.
A substrate processing method characterized in that the rotation speed of the substrate in the steps a) and b) is 50 to 300 rpm. The substrate processing method according to any one of claims 1 to 7.
A laminated film including a plurality of first material films formed of the first material and a plurality of second material films formed of a second material different from the first material is the one main surface of the substrate. It is provided in the processing area in
Before the step b), a hole extending in the thickness direction is formed in the laminated film.
A substrate processing method, characterized in that, in the step b), the plurality of second material films contained in the laminated film are selectively etched through the pores. The substrate processing method according to any one of claims 1 to 8.
A substrate treatment method, wherein the etching solution is alkaline. It is a board processing device
A board holding part that holds a disk-shaped board in a horizontal state,
A board rotation mechanism that rotates the board holding portion around a central axis facing in the vertical direction,
An oxidant liquid supply unit that supplies the oxidant liquid to the peripheral edge of the one main surface by ejecting the oxidant liquid that oxidizes one main surface of the substrate from a nozzle toward the rotating substrate.
A process of ejecting an etching solution for etching the one main surface from a nozzle toward the central portion of the one main surface of the rotating substrate so as to be located inside the peripheral portion on the one main surface. An etching solution supply unit that supplies the etching solution to the region,
A substrate processing apparatus characterized by comprising. The substrate processing apparatus according to claim 10.
The peripheral portion of the one main surface is characterized in that the oxide liquid discharged from the nozzle of the oxide liquid supply unit and the etching liquid discharged from the nozzle of the etching liquid supply unit are mixed. Board processing equipment.

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