JP3768802B2 - Substrate processing method and substrate processing apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a substrate processing method and a substrate processing apparatus for removing metal deposits on a substrate with a processing liquid, for example, in a semiconductor device manufacturing process.
[0002]
[Prior art]
In recent years, in the semiconductor device manufacturing process, design rules have been increasingly miniaturized, and accordingly, from the viewpoint of speeding up, Cu having lower electrical resistance is being used as a wiring layer in place of conventional Al.
[0003]
When the Cu wiring layer is formed in multiple layers, a lower Cu wiring layer is formed on a semiconductor wafer which is a substrate to be processed, and a SiN barrier layer and an interlayer insulating layer are sequentially formed on the Cu wiring layer. A resist pattern is formed thereon by a lithography technique, and a contact hole reaching the metal wiring layer is formed by dry-etching a film formed on the semiconductor wafer according to the pattern using the resist as a mask. Thereafter, the resist mask is removed by dry ashing, and then the remaining resist mask and the polymer layer which is an etching residue in the hole are removed with hydrofluoric acid (HF), sulfuric acid (H₂SO₄Or an upper layer Cu wiring and a buried layer are formed on the interlayer insulating layer and in the contact hole.
[0004]
By the way, in the dry etching, the interlayer insulating layer is etched by plasma of the etching gas while forming the polymer layer on the side wall of the hole, so that the polymer layer remains in the hole as described above. When Cu reaches the Cu wiring layer, Cu is sputtered and scattered, so that the sputtered Cu adheres onto the polymer layer. Therefore, it is necessary to remove this Cu deposit along with the polymer layer.
[0005]
On the other hand, Cu is used as a plating metal in the semiconductor device manufacturing process, but Cu may adhere to the back surface of the semiconductor wafer during plating. It is necessary to remove the Cu adhering in this way, and in this case as well, it is conceivable to clean with the above-described cleaning treatment liquid.
[0006]
[Problems to be solved by the invention]
However, Cu is not removed by simply supplying the cleaning treatment liquid, and it is necessary to oxidize Cu to CuO once. That is, in the state of Cu, it is insoluble in the cleaning treatment solution, but becomes soluble in the cleaning treatment solution by being oxidized to CuO and can be removed.
[0007]
For this reason, in any of the above cases, when treated in air, it is conceivable that the Cu deposits are oxidized and then dissolved and removed with a chemical solution, but in this case, the Cu wiring layer and the Cu plating layer are dissolved. It is removed and damages these metal layers.
[0008]
This invention is made | formed in view of this situation, Comprising: It aims at providing the substrate processing method and substrate processing apparatus which can remove the metal adhering to a board | substrate without damaging a metal layer.
[0012]
[Means for Solving the Problems]
  To solve the above problem,First of the present invention1According to the aspect of the present invention, there is provided a substrate processing method for removing a polymer layer and metal deposits attached to a substrate having a metal layer with a processing liquid,
  Loading the substrate into the chamber;
  SaidIntroducing an inert gas into the chamberSaidMake the chamber an inert gas atmosphere,SaidSupplying a treatment liquid into the chamber to dissolve and remove the polymer layer;
  Introducing an inert gas and an oxygen-containing gas into the chamber;SaidInside the chamberIt is possible to oxidize the metal depositOxygen concentrationInert gasAtmosphereSaidSupplying a treatment liquid into the chamber and dissolving and removing deposits oxidized by oxygen in the atmosphere in the chamber;
A substrate processing method is provided.
[0013]
In this case, the step of dissolving and removing the deposit may be performed after the step of dissolving and removing the polymer layer, or may be performed before the step of dissolving and removing the polymer layer. Further, the step of dissolving and removing the polymer layer and the step of dissolving and removing the deposit may be alternately performed so that at least one step is performed a plurality of times.
[0014]
  First of the present invention2According to the above aspect, at least a metal layer and an insulating layer thereover are formed on the substrate, and the insulating layer exists after the etching until the metal layer is etched.,A substrate processing method for removing metal deposits deposited by sputtering a metal layer with a processing solution,
  Loading the etched substrate into the chamber;
  SaidIntroducing an inert gas into the chamberSaidMake the chamber an inert gas atmosphere,SaidSupplying a treatment liquid into the chamber to dissolve and remove the polymer layer to expose metal deposits;
  Thereafter, an oxygen-containing gas is introduced into the chamber,SaidInside the chamberIt is possible to oxidize the metal depositOxygen concentrationInert gasAn atmosphere, supplying a treatment liquid into the chamber, and dissolving and removing exposed deposits oxidized by oxygen in the chamber atmosphere;
  Then stop supplying oxygen-containing gas and againSaidMake the chamber an inert gas atmosphere,SaidSupplying a treatment liquid into the chamber and dissolving and removing the remaining polymer layer;
A substrate processing method is provided.
[0015]
  First of the present invention3According to the above aspect, the resist mask, the polymer layer, and the interior of the polymer layer that remain after forming at least the metal layer and the insulating layer thereover on the substrate and etching the insulating layer until reaching the metal layer using the photoresist layer as a mask A substrate processing method for removing metal deposits deposited by sputtering of a metal layer existing in a processing solution,
  Loading the etched substrate into the chamber;
  SaidIntroducing an inert gas into the chamber to make the chamber an inert gas atmosphere, supplying a treatment liquid into the chamber and dissolving and removing the resist mask;
  Inert gas atmosphereSaidSupplying a treatment liquid into the chamber to dissolve and remove the polymer layer, and exposing a metal deposit inside the polymer layer;
  Thereafter, an oxygen-containing gas is introduced into the chamber,SaidInside the chamberIt is possible to oxidize the metal depositOxygen concentrationInert gasAn atmosphere, supplying a treatment liquid into the chamber, and dissolving and removing exposed deposits oxidized by oxygen in the chamber atmosphere;
  Thereafter, the supply of the oxygen-containing gas is stopped, and the inside of the chamber is made an inert gas atmosphere again.SaidSupplying a treatment liquid into the chamber and dissolving and removing the remaining polymer layer;
A substrate processing method is provided.
[0016]
  Above3In this aspect, the step of dissolving and removing the resist mask and the step of dissolving and removing the polymer layer and exposing the metal deposit inside the polymer layer can be performed simultaneously.
[0017]
  First of the present invention4From the point of viewA first deposit made of a polymer attached to a substrate having a metal layer, a second deposit containing a metal, and a third deposit containing a metal and having a composition different from that of the second deposit A substrate processing method for removing the substrate with a processing solution,
Loading the substrate into the chamber;
Introducing an inert gas into the chamber to make the chamber an inert gas atmosphere, supplying a treatment liquid into the chamber to dissolve and remove the first deposit made of polymer;
An inert gas and an oxygen-containing gas are introduced into the chamber so that the inside of the chamber has an inert gas atmosphere having an oxygen concentration that can oxidize the second deposit, and a treatment liquid is contained in the chamber. And dissolving and removing the second deposit oxidized by oxygen in the atmosphere in the chamber;
An inert gas and an oxygen-containing gas are introduced into the chamber so that the inside of the chamber has an inert gas atmosphere having an oxygen concentration that can oxidize the third deposit, and a treatment liquid is contained in the chamber. And dissolving and removing the third deposit oxidized by oxygen in the atmosphere in the chamber;
A substrate processing method comprising:Is provided.
[0018]
  Above4In this aspect, the first deposit is obtained by performing the dissolution and removal treatment in the atmosphere having the first oxygen concentration, and the second deposit is obtained by performing the dissolution and removal treatment in the atmosphere having the second oxygen concentration. Can be removed. Further, the third deposit can be removed by performing the dissolution removal treatment of the deposit at a third oxygen concentration different from the first and second oxygen concentrations.
[0019]
  Above2Perspective and number3In this aspect, the step of dissolving and removing the deposit and the step of dissolving and removing the remaining polymer layer may be alternately performed so that at least one step is performed a plurality of times.
[0020]
  Above1Point of view, no.2Point of view, and3In this aspect, the polymer layer is preferably dissolved and removed by repeatedly supplying the treatment liquid and removing the treatment liquid from the substrate. In addition, the above3In this aspect, the resist mask is preferably dissolved and removed by repeatedly supplying the treatment liquid and removing the treatment liquid from the substrate.
[0021]
  In addition, the above1Point of view, no.2Point of view, and3In the substrate processing method according to the above aspect, when oxidizing the metal deposit, it is preferable to control the oxygen concentration in the chamber in accordance with the adhesion state of the metal deposit. Furthermore, Cu, Ru and Pt can be cited as applicable metal deposits in any of the above substrate processing methods. Furthermore, the above4The substrate processing method according to the above aspect is applied to the treatment of deposits including a first deposit mainly composed of a polymer and a second deposit mainly composed of at least one of Cu, Ru and Pt. Can do.
[0022]
In any of the above substrate processing methods, it is preferable that the deposits are dissolved and removed by repeatedly supplying the processing liquid and removing the processing liquid from the substrate.
[0023]
  First of the present invention5According to the viewpoint, adhered to the substrate having a metal layerWith polymer layerMetal depositsWhenA substrate processing apparatus for removing the substrate with a processing liquid,
  A chamber for housing the substrate;
  An inert gas introduction means for introducing an inert gas into the chamber;
  Oxygen gas introducing means for introducing oxygen-containing gas into the chamber;
  An exhaust means for exhausting the chamber;
  First treatment liquid introduction means for introducing a first treatment liquid for removing the polymer layer attached to the substrate in the chamber;
  Remove metal deposits on the substrate in the chamberSecondIntroduce treatment solutionSecondTreatment liquid introduction means;
  A drainage means for draining the processing liquid supplied into the chamber;
Equipped withAnd
  When removing the polymer layer, an inert gas is introduced into the chamber to make the chamber an inert gas atmosphere, and a first treatment liquid is supplied into the chamber.
  When removing the metal deposit, an inert gas and an oxygen-containing gas are introduced into the chamber so that the inside of the chamber has an inert gas atmosphere with an oxygen concentration sufficient to oxidize the metal deposit. While supplying the second processing liquid into the chamberA substrate processing apparatus is provided.
[0025]
  First of the present invention1According to this aspect, the substrate is loaded into the chamber, an inert gas is introduced into the chamber to make the chamber an inert gas atmosphere, and then the treatment liquid is supplied into the chamber to remove the polymer layer. Introducing an inert gas and oxygen-containing gas into the chamberIt is possible to oxidize the metal depositOxygen concentrationInert gasSince the processing solution is supplied into the chamber after the atmosphere has been set up and the deposits oxidized by oxygen in the chamber atmosphere are dissolved and removed, the metal deposits are oxidized and removed when the metal deposits are removed. The amount of oxygen necessary to enable the treatment can be reduced, and the removal of the polymer layer is performed in an atmosphere that does not substantially contain oxygen gas. Metal deposits can be removed without causing damage to the metal layer. Specifically, the first aspect of the present invention.2As described above, at least a metal layer and an insulating layer thereon are formed on the substrate, and after the insulating layer is etched until it reaches the metal layer, the remaining polymer layer and the metal layer existing inside the polymer layer are sputtered and adhered. By performing such treatment when removing the deposited metal deposits with the treatment liquid, the metal deposits can be removed without causing damage to the metal layer by the treatment liquid as much as possible by preventing the metal layer from being oxidized. Can do.
[0026]
  First of the present invention3According to the above aspect, the resist mask, the polymer layer, and the interior of the polymer layer that remain after forming at least the metal layer and the insulating layer thereover on the substrate and etching the insulating layer until reaching the metal layer using the photoresist layer as a mask In removing the metal deposits deposited by sputtering the metal layer present in the substrate, the substrate after etching is loaded into the chamber, an inert gas is introduced into the chamber, and the chamber is filled with the inert gas. The atmosphere is removed, the resist mask and the polymer layer are removed, and metal deposits inside the polymer layer are exposed. Then, an oxygen-containing gas is introduced into the chamber,It is possible to oxidize the metal depositOxygen concentrationInert gasIn this state, a processing solution is supplied into the chamber to dissolve and remove the exposed deposits oxidized by oxygen in the atmosphere in the chamber. Since the remaining polymer layer is removed by supplying the treatment liquid into the chamber after making the atmosphere of inert gas, the minimum necessary to oxidize the metal deposit and make it removable when removing the metal deposit The amount of oxygen can be limited, and the resist mask and the polymer layer are removed in an atmosphere that does not substantially contain oxygen gas. The metal deposit can be removed without causing any damage.
[0027]
  First of the present invention5According to the above aspect, an inert gas introducing means for introducing an inert gas into the chamber, an oxygen gas introducing means for introducing an oxygen-containing gas into the chamber,First treatment liquid introduction means for introducing a first treatment liquid for removing the polymer layer attached to the substrate in the chamber;Remove metal deposits on the substrate in the chamberSecondIntroduce treatment solutionSecondA treatment liquid introduction means,When removing the polymer layer, an inert gas is introduced into the chamber to make the chamber an inert gas atmosphere, and the first treatment liquid is supplied into the chamber to remove metal deposits. Introducing an inert gas and an oxygen-containing gas into the chamber so that the inside of the chamber is an inert gas atmosphere having an oxygen concentration that can oxidize the metal deposit, and the second treatment is performed in the chamber. Supply liquidSoWhen removing metal deposits, the minimum amount of oxygen necessary to oxidize and remove the metal deposits can be obtained, and when removing the polymer layer, oxygen gas is substantially contained. Since it is performed in a non-atmosphere, the metal deposit can be removed without causing the metal layer to be oxidized as much as possible and causing no damage to the metal layer by the treatment liquid.
[0028]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. 1 and 2 are sectional views showing a substrate processing apparatus for carrying out the method of the present embodiment. FIG. 1 shows a state in which an inner chamber 8 is arranged inside an outer chamber 7, and FIG. The state where the chamber 8 is taken out of the outer chamber 7 is shown. FIG. 3 is a cross-sectional view taken along the line AA in FIG.
[0029]
The substrate processing apparatus 1 removes a resist mask, a polymer layer that is an etching residue, and metal deposits that are sputtered and attached after etching of a semiconductor wafer (hereinafter simply referred to as a wafer) W. The provided support wall 2, the motor 3 fixed to the support wall 2 with the rotary shaft 4 horizontal, the rotor 5 attached to the rotary shaft 4 of the motor 3, and the motor 5 attached horizontally to the support wall 2, 3 and a cylindrical casing 6 surrounding the rotary shaft 4, an outer chamber 7 supported by the casing 6 and configured to surround the rotor 5, and an inner side of the outer chamber 7 as shown in FIG. And an inner chamber 8 for performing the chemical treatment in the state.
[0030]
The rotor 5 can hold a plurality of (for example, 26) vertical wafers W arranged in a horizontal direction. Together with the held plurality of wafers W, the rotor 3 is rotated by the motor 3 via the rotating shaft 4. It is designed to be rotated. The structure of the rotor 5 will be described later.
[0031]
The outer chamber 7 has a vertical wall 7 a on the motor 3 side, a vertical wall 7 b on the tip side, and a cylindrical outer cylinder 7 c provided outside the rotor 5 at a predetermined interval. A seal mechanism 90 (to be described later) is provided at the center of the vertical wall 7b to seal between the rotary shaft 4 and the center. The outer cylinder 7c can be retracted to the casing 6 side when the wafer W is loaded.
[0032]
The inner chamber 8 has a cylindrical inner cylinder 8a having a smaller diameter than the outer cylinder 7c of the outer chamber 7, and the inner cylinder 8a is movable between the chemical solution processing position of FIG. 1 and the retracted position of FIG. It has become. As shown in FIG. 1, when the inner cylinder 8a is in the chemical solution processing position inside the outer cylinder 7c of the outer chamber 7, a processing space 30 defined by the inner cylinder 8a and the vertical walls 7a and 7b is formed. 2, when the inner cylinder 8a is in the retracted position, a processing space 20 defined by the outer chamber 7 is formed. Note that the processing space 20 and the processing space 30 are sealed by a sealing mechanism.
[0033]
In the vicinity of the upper end of the processing space 20, two discharge nozzles 22 (see FIG. 3) having a large number of discharge ports 21 are arranged along the horizontal direction. From the discharge nozzle 22, pure water, IPA, N supplied from a supply source (not shown)₂Gas and various chemicals can be discharged.
[0034]
Near the upper end of the processing space 30, two discharge nozzles 32 having a large number of discharge ports 31 are provided in a state of being attached to the inner cylinder 8 a. From the discharge nozzle 32, various chemicals supplied from a supply source (not shown), pure water, IPA, N₂Gas can be discharged.
[0035]
The chemical liquid (processing liquid) discharged from the discharge nozzles 22 and 32 can dissolve and remove the resist, the polymer layer, and the metal deposit. Examples of such chemical liquid include hydrofluoric acid (HF) and sulfuric acid (H₂SO₄), Or organic release agents.
[0036]
A lower portion of the vertical wall 7b on the front end side of the outer chamber 7 is provided with a first drain port 41 for discharging the used chemical solution, pure water, and IPA from the processing space 30 in the state of FIG. Below the first drainage port 41, a second drainage port 42 for discharging the used chemical solution, pure water, and IPA from the processing space 20 in the state of FIG. 2 is provided. A first drain pipe 43 and a second drain pipe 44 are connected to the first drain port 41 and the second drain port 42, respectively.
[0037]
Further, a first exhaust port 45 for exhausting the processing space 30 in the state of FIG. 1 is provided above the vertical wall 7b, and above the first exhaust port 45, the processing space in the state of FIG. A second exhaust port 46 for exhausting 20 is provided. A first exhaust pipe 47 and a second exhaust pipe 48 are connected to the first exhaust port 45 and the second exhaust port 46, respectively.
[0038]
Further, an inert gas such as N is added to the processing space 30 at the center of the vertical wall 7b.₂An inert gas introduction port 51 for introducing gas, Ar gas, and the like, and an oxygen-containing gas such as O₂Gas, air, ozone (O₃) And the like, an oxygen-containing gas introduction port 52 is provided. An inert gas supply pipe 53 is connected to the inert gas introduction port 51, and the inert gas is supplied from the inert gas supply source 54 to the processing space 30 through the inert gas supply pipe 53. An oxygen-containing gas supply pipe 56 is connected to the oxygen-containing gas introduction port 52, and oxygen-containing gas is supplied from the oxygen-containing gas supply source 57 to the processing space 30 through the oxygen-containing gas supply pipe 56. Heaters 54a and 57a are respectively attached to the inert gas supply source 54 and the oxygen-containing gas supply source 57, and the inert gas and the oxygen-containing gas introduced into the processing space 30 are heated by the heaters 54a and 57a. By increasing the temperature in the chamber, it is possible to promote the dissolution reaction by the chemical solution. The inert gas supply pipe 53 and the oxygen-containing gas supply pipe 56 are provided with mass flow controllers 55 and 58, respectively.₂Gas and O₂The gas flow rate is controlled, and the atmosphere in the processing space 30 can be adjusted.
[0039]
The inert gas supply source 54 is further connected to inert gas supply pipes 53a and 53b provided with mass flow controllers 55a and 55b, respectively. The oxygen-containing gas supply source 57 is connected to oxygen-containing gas supply pipes 56a and 56b provided with mass flow controllers 58a and 58b, respectively. The inert gas supply pipe 53a and the oxygen-containing gas supply pipe 56a merge to form a gas supply pipe 53c, and the inert gas supply pipe 53b and the oxygen-containing gas supply pipe 56b merge to form a gas supply pipe 53d. It has become. The gas supply pipe 53c is connected to a cylindrical body 310, which will be described later, provided at the center of the vertical wall 7a. The gas supply pipe 53d branches into two systems and is connected to a boss 301 near the switching member 292a or 292b described later.
[0040]
The flow rate of these mass flow controllers 55, 55 a, 55 b, 58, 58 a and 58 b is controlled by the controller 60. A flow meter may be provided instead of the mass flow controller, and the flow rate may be adjusted manually.
[0041]
A switching mechanism 80 (to be described later) for switching the rotor 5 between the holding state and the released state is provided at a predetermined position of the vertical wall 7a.
[0042]
As shown in FIG. 4, the rotor 5 includes a pair of disks 270a and 270b arranged at a predetermined interval, and a first locking member that is installed on the disks 270a and 270b and that forms a pair on each side. 271a, 271b, second locking members 272a, 272b, and a pair of holding mechanisms 273a, 273b for holding the wafer W locked by the locking members 271a, 271b, 272a, 272b from below. .
[0043]
The first locking members 271a and 271b and the second locking members 272a and 272b have a plurality of grooves 275, and the wafer W is locked in a state where the peripheral edge of the wafer W is inserted into the grooves 275. Is configured to do. Note that a pressure sensor is attached to any of these locking members.
[0044]
The holding mechanism 273a includes an arm 280a arranged inside the disk 270a, a balance weight 281a arranged outside the disk 270a, an arm 284a arranged inside the disk 270b, and an outside of the disk 270b. A balance weight 285a and a holding member 283a for connecting the arms 280a and 284a are provided. The arm 280a and the balance weight 281a are connected to each other by a rotating shaft that passes through the disk 270a, and the arm 284a and the balance weight 285a are connected to each other by a rotating shaft that passes through the disk 270b, and rotate integrally. ing. On the other hand, the holding mechanism 273b, like the holding mechanism 273a, has an arm 280b arranged inside the disk 270a, a balance weight 281b arranged outside the disk 270a, an arm 284b arranged inside the disk 270b, A balance weight 285b disposed outside the disk 270b and a holding member 283b for connecting the arms 280b and 284b are provided. The arm 280b and the balance weight 281b are connected to each other by a rotating shaft that passes through the disk 270a, and the arm 284b and the balance weight 285b are connected to each other by a rotating shaft that passes through the disk 270b. ing. A plurality of grooves 286 into which the periphery of the wafer W is inserted are formed in the holding members 283a and 283b of the holding mechanisms 273a and 273b.
[0045]
Further, lock pins 287 for locking the balance weights 281a, 281b, 285a, 285b when the holding mechanisms 273a, 273b are closed are provided on the outer surfaces of the disks 270a, 270b. The lock pin 287 also functions as a stopper for preventing the balance weights 281a, 281b, 285a, 285b from opening more than necessary and hitting the chamber wall. Furthermore, as shown in FIGS. 5 and 6, the balance weights 285a and 285b are provided with projections 288a and 288b inserted into grooves 293a and 293b of switching members 292a and 292b, which will be described later, respectively.
[0046]
As shown in FIGS. 5 and 6, a circumferential guide groove 290 is formed in the vertical wall 7 a on the motor 3 side, and a position corresponding to the holding mechanisms 273 a and 273 b in the middle of the guide groove 290. Circular openings 291a and 291b are formed. Then, cylindrical switching members 292a and 292b are inserted into the openings 291a and 291b, respectively, so as to be rotatable in the θ direction. These switching members 292 a and 292 b function as one component of the switching mechanism 80. Arc-shaped grooves 293a and 293b are formed in front of the switching members 292a and 292b, respectively, and these grooves 293a and 293b are connected to the guide groove 290 by rotating the switching members 292a and 292b. Switching between a state (see FIG. 7) and a state not continuous with the guide groove 290 (see FIG. 6) is possible. In addition, protrusions 288a and 288b provided on the balance weights 285a and 285b are inserted into the grooves 293a and 293b, and a holding mechanism is provided via the balance weights 285a and 285b by the rotation of the switching members 292a and 292b. 273a and 273b can be switched between the holding state and the release state.
[0047]
When the switching members 292a and 292b are rotated so that the grooves 293a and 293b do not continue to the guide groove 290 and the balance weights 285a and 285b are in the vertical posture as shown in FIG. 8, the holding mechanisms 273a and 273b Is in the holding release state indicated by the solid line in FIG.
[0048]
On the other hand, as shown in FIG. 7, the switching members 292a and 292b are connected to the guide grooves 290 so that the balance weights 285a and 285b are opened on the upper side so that the holding mechanisms 273a and 293b are opened. 273b is in a closed state indicated by a two-dot chain line in FIG. Thus, when the holding mechanisms 273a and 273b are in the holding state, a plurality of, for example, 26 wafers W locked by the locking members 271a, 271b, 272a and 272b are held from below by the holding members 283a and 283b. At the same time, when the guide groove 290 continues, the protrusions 288a and 288b can move along the guide groove 290, and the rotor 5 can be rotated while maintaining the holding state. In this case, the holding mechanisms 273a and 273b are kept constant regardless of the rotation angle of the rotor 5, so that the holding of the wafer W is not released when the rotor 5 is rotated. For this reason, it is possible to prevent the wafer W from protruding from the rotor 5 during the cleaning process or the drying process to prevent the supply of the cleaning liquid or the dry gas, or the wafer W from jumping out of the rotor 5 and being damaged.
[0049]
Next, the switching mechanism 80 including the switching members 292a and 292b and the surrounding structure will be described. In the switching mechanism 80, since the structure on the switching member 292a side and the structure on the switching member 292b side are substantially the same, only the structure on the switching member 292a side will be described here. FIG. 9 is an enlarged cross-sectional view schematically showing a portion of the switching mechanism 80 on the switching member 292a side and its peripheral portion.
[0050]
As shown in FIG. 9, a boss 301 having a through hole continuous with the opening 291a is disposed on the motor 3 side of the opening 291a provided in the vertical wall 7a. The switching member 292a The boss 301 is inserted into the through hole with a slight clearance 302. A gap 305 is formed between the tip of the switching member 292a and the opening 291a. A rotating cylinder 300 is provided on the motor 3 side of the boss 301, and the switching member 292 a is connected to the rotating cylinder 300 and is rotated by operating the rotating cylinder 300.
[0051]
A ring-shaped passage 303 is formed inside the boss 301, and the above-described gas supply pipe 53 d is connected to a predetermined portion of the passage 303. In addition, a narrow ring-shaped passage 304 extending toward the processing space 20 or 30 is provided inside the boss 301 so as to be continuous with the ring-shaped passage 303, and this passage 304 is a switching member. It communicates with a gap 305 between 292a and the vertical wall 7a. In such a configuration, by supplying an inert gas and / or an oxygen-containing gas via the gas supply pipe 53d, the gas flows from the passage 303 through the passage 304 into the processing space 20 or 30 through the gap 305. In this way, the inert gas and / or oxygen-containing gas can be supplied into the processing space 20 or 30 to assist the atmosphere adjustment, and the gap 305 between the switching member 292a and the vertical wall 7a. Therefore, it is possible to prevent the treatment liquid from being accumulated. When the processing liquid is accumulated and dried, it becomes particles and causes wafer contamination. However, by preventing the processing liquid from accumulating, such a problem is eliminated.
[0052]
Next, the seal mechanism 90 provided at the center of the vertical wall 7a will be described. FIG. 10 is an enlarged cross-sectional view showing a detailed structure of the sealing mechanism 90 schematically shown in FIG. 1 and its peripheral portion.
[0053]
As shown in FIG. 10, a hollow cylindrical body 310 is disposed at the center of the vertical wall 7 a so as to surround the rotation shaft 4, and between the distal end portion 310 a of the cylindrical body 310 and the rotation shaft 4. Is provided with a slight gap 312. A bearing 313 and a fluid seal member 9 are provided between the cylindrical body 310 and the rotary shaft 4, and the cylindrical body 310 seals the rotary shaft 4 so as to be rotatable. A ring-shaped passage 311 is provided between the cylindrical body 310 and the bearing 313, and the gas supply pipe 53 c and the gas discharge pipe 54 e for discharging the gas in the passage 311 are provided in the passage 311. It is connected. The passage 311 communicates with the processing space 20 or 30 through the gap 312. In such a configuration, by supplying an inert gas and / or an oxygen-containing gas through the gas supply pipe 54c, the gas passes through the gap 312 from the passage 311 and the processing space 20 or as indicated by an arrow in the figure. 30 flows in. In this way, the inert gas and / or oxygen-containing gas can be supplied into the processing space 20 or 30 to assist the atmosphere adjustment, and the processing liquid is placed in the gap 312 around the rotating shaft 4. Can be prevented from accumulating.
[0054]
Next, an operation when the chemical processing of the semiconductor device (wafer W) etched in the process shown in FIG. 11 is performed by the substrate processing apparatus 1 configured as described above will be described.
[0055]
First, the process of FIG. 11 will be described. As shown in FIG. 11A, a Cu wiring layer 71, a SiN barrier layer 72, and an interlayer insulating layer 73 are formed on a wafer W made of silicon, and a resist layer 74 is formed thereon, and photolithography is performed. A predetermined wiring pattern is formed on the resist layer 74 by a technique. The interlayer insulating layer 73 is made of SiO.₂It may be a film, or may be a so-called low-k film made of an organic low dielectric constant material that has been used recently for speeding up.
[0056]
Next, as shown in FIG. 11B, contact holes 75 are formed by plasma etching using plasma of a predetermined etching gas, using the resist layer 74 as a mask (resist mask). At this time, a polymer layer 76 is formed on the side wall of the contact hole 75 due to the etching gas component. In the etching, the polymer layer 76 acts as a protective layer, and etching with high anisotropy is performed.
[0057]
When the etching progresses and reaches the Cu wiring layer 71 as shown in FIG. 11C, Cu is sputtered and the Cu deposit 77 adheres to the outside of the polymer layer 76. Even after the etching reaches the Cu wiring layer 71, the predetermined over-etching is performed. As a result, a polymer is formed again, and the polymer layer 78 is formed outside the Cu deposit 77 as shown in FIG. It is formed. Accordingly, Cu is present inside the polymer layer.
[0058]
The wafer W in the state shown in FIG. 11D is processed by the substrate processing apparatus 1. As described below, this treatment removes the resist mask (resist layer), the polymer layer, and the Cu deposits. In this process, first, with the outer cylinder 7c of the outer chamber 7 and the inner cylinder 8a of the inner chamber 8 retracted onto the casing 6, a plurality of wafers W are transferred to the rotor 5 from below by a transfer means (not shown). The wafer W is mounted and the holding mechanisms 273a and 273b are held to hold the wafer W. At this time, the wafer W is prevented from being destroyed by being mounted on the rotor 5 while detecting the pressure received by the wafer W by the pressure sensor described above. Then, the outer cylinder 7c and the inner cylinder 8a are arranged outside the rotor 5 to form a sealed processing space 30 as shown in FIG.
[0059]
Next, from the viewpoint of preventing oxidation of the Cu wiring layer 71 as much as possible, an inert gas is supplied from the inert gas supply source 54 to the processing space 30 through the inert gas supply pipe 53 and the inert gas introduction port 51. The processing space 30 is an inert gas atmosphere substantially free of oxygen.
[0060]
Thereafter, the rotor 5 is rotated at a low speed of 1 to 500 rpm by rotational driving by the motor 3, and a predetermined chemical solution (processing solution) is discharged from the discharge nozzle 32 while rotating the wafer W, and the resist mask and the polymer layer are removed. Dissolve and remove.
[0061]
In removing the resist mask and the polymer layer, first, a predetermined chemical solution is discharged from the discharge nozzle 32 for several tens of seconds. At this time, the discharged chemical is diffused on the surface of the wafer W by rotating the wafer W together with the rotor 5 at a low speed of 1 to 500 rpm. In this case, by controlling the rotation speed of the rotor 5 according to the viscosity of the chemical solution, the chemical solution can be uniformly diffused on the surface of the wafer W, and the resist mask and the polymer layer can be uniformly dissolved. . For example, when the viscosity of the chemical solution is high, the rotor 5 is rotated at a relatively high rotational speed within the above range, and when the viscosity is low, the rotor 5 is rotated at a relatively low rotational speed. Thus, the chemical solution can be uniformly diffused.
[0062]
When the resist mask and the polymer layer are dissolved in this way, the chemical solution that has undergone dissolution reaction will stay on the surface of the wafer W. Since the reaction rate of the dissolved chemical solution is low, when such a dissolved chemical solution stays, the discharge of the chemical solution is once stopped and the heated N₂The gas is discharged from the discharge nozzle 32 for several seconds and the output of the motor 3 is increased so that the rotational speed of the rotor 5 is about 100 to 3000 rpm, which is higher than the rotational speed when supplying the chemical solution. Thereby, the chemical solution after the dissolution reaction is removed from the wafer W by the supply pressure of the inert gas and the centrifugal force generated by the rotation of the rotor 5. At this time, in order to effectively remove the dissolved chemical solution, the rotation speed of the rotor 5 is preferably controlled according to the viscosity of the chemical solution.
[0063]
As described above, after the chemical solution after the dissolution reaction is removed from the surface of the wafer W, the rotational speed of the rotor 5 is set again to 1 to 500 rpm, and a new chemical solution is discharged from the discharge nozzle 32. The process of supplying the chemical solution and the process of removing the dissolved chemical solution are repeated several times to several thousand times, thereby constantly supplying a new highly reactive chemical solution to the surface of the wafer W. The resist mask and the polymer layer can be efficiently removed.
[0064]
In this manner, the resist mask (resist layer) 74 and the polymer layer 78 are removed, and a part of the polymer layer 76 is also removed. However, since the inside of the processing space 30 is an inert gas atmosphere, the Cu deposit 77 is oxidized. Therefore, since it is not dissolved in the chemical solution, it remains without being removed together with the surrounding polymer layer as shown in FIG. That is, the hydrofluoric acid (HF) and sulfuric acid (H₂SO₄) However, chemicals such as organic stripping agents cannot be dissolved in the state of Cu, and can be dissolved by becoming CuO. Therefore, although the oxidation of the Cu wiring layer 71 is suppressed by an inert gas atmosphere, it is attached to Cu. The kimono 77 cannot be removed.
[0065]
Therefore, in this embodiment, after removing the resist mask and the polymer layer as described above, the oxygen-containing gas is supplied from the oxygen-containing gas supply source 57 in a state where the supply of the inert gas from the inert gas supply source 54 is continued. An oxygen-containing gas is supplied to the processing space 30 via the supply pipe 56 and the oxygen-containing gas introduction port 52, and the processing space 30 is set to an inert atmosphere having a predetermined oxygen concentration. In this case, the oxygen concentration is controlled by controlling the mass flow controllers 55 and 58 by the controller 60 so as to obtain a predetermined flow rate.
[0066]
After controlling the atmosphere in the processing space 30 as described above, the chemical solution is discharged from the discharge nozzle 32 while the rotor 5 is rotated in the same manner as in the conventional resist mask and polymer layer removal processing. At this time, since the Cu deposit is oxidized by the oxygen in the atmosphere to become CuO, the oxidized CuO deposit is dissolved and removed by the supplied chemical solution, as shown in FIG. .
[0067]
When removing such Cu deposits, if the removal treatment is performed in the air, the Cu deposits are surely oxidized and dissolved and removed by the chemical solution. In this case, the Cu wiring layer is also oxidized. A considerable part is dissolved and removed. On the other hand, as in this embodiment, by performing the treatment in an atmosphere in which a small amount of oxygen-containing gas is introduced into an inert gas atmosphere, the amount of the Cu wiring layer dissolved and removed is reduced as much as possible. The kimono can be removed.
[0068]
In this case, it is preferable to control the oxygen concentration in accordance with the adhesion state of the Cu deposit 77 and so as not to damage the Cu wiring layer 71 as much as possible. The appropriate oxygen concentration at this time varies depending on the state of Cu deposits, etc., but is set to a predetermined concentration of, for example, about 5% or less. In this case, the oxygen concentration can be controlled by switching the gas itself in addition to the concentration control of the oxygen-containing gas itself. For example, air and O₂Gas switching or the like can be considered.
[0069]
Thus, also when removing the Cu deposit 77, after discharging the chemical solution for a predetermined time, N₂The dissolved chemical solution is removed from the surface of the wafer W by discharging the gas and increasing the rotational speed of the rotor 5, and the Cu deposits are efficiently removed by repeating these steps several to several thousand times. be able to. This method is more effective because Cu deposits exposed when the chemical solution is removed can be oxidized by oxygen in the atmosphere.
[0070]
After removing the Cu deposit 77 in this manner, the supply of the oxygen-containing gas is stopped, the inside of the processing space 30 is again made an inert gas atmosphere substantially free of oxygen, and the previous resist mask and polymer layer are removed. In exactly the same manner as the treatment, the remaining polymer layer 76 is removed while preventing the oxidation of the Cu wiring layer 71 by repeatedly performing the chemical supply and the chemical removal after the dissolution reaction, and the state shown in FIG. It can be.
[0071]
After the removal process of the resist mask, the polymer layer, and the Cu deposit is completed in this manner, IPA or pure water is discharged from the discharge nozzle 32 to wash away the remaining reaction product from the wafer W.
[0072]
Next, the inner cylinder 8 a is retracted from the inside of the outer cylinder 7 c to the outside of the casing 6 so that the wafer W is positioned in the processing space 20 formed in the outer chamber 7. In this state, pure water is discharged from the discharge nozzle 22 to rinse the wafer W, and finally the rotor 5 is rotated at high speed to spin dry the wafer W.
[0073]
As described above, when removing Cu deposits, since a small amount of oxygen-containing gas is added to the inert gas atmosphere, the minimum oxygen amount necessary to oxidize and remove Cu deposits In addition, since the resist mask and the polymer layer are removed in an atmosphere substantially free of oxygen, the Cu wiring layer is prevented from being oxidized as much as possible, and the Cu wiring layer is hardly dissolved and removed. The resist mask, polymer layer, and Cu deposits can be removed with less damage to the wiring layer.
[0074]
Conventionally, when Cu is sputtered and deposited, the Cu wiring layer must be removed in order to remove it, so a method has been adopted in which Cu sputtering does not occur during etching. That is, in the state shown in FIG. 11A, first, only the interlayer insulating layer 73 is etched, the resist mask and the polymer layer are subsequently removed, and then the SiN barrier layer 72 is used using radicals having lower energy than ions. Was etched to prevent Cu sputtering. However, in this case, the process becomes complicated and radical etching is isotropic etching, so that the etching shape of the SiN barrier layer 72 is deteriorated. On the other hand, in this embodiment, since Cu deposits can be removed without damaging the Cu wiring layer 71, problems such as complicated processes and poor etching shapes arise. Absent.
[0075]
In the above embodiment, the resist mask and the polymer layer are first removed at the same time. However, they may be removed in different steps using different chemical solutions. In this case, for example, first, the chemical solution for removing the resist mask is supplied from the discharge nozzle 32 to the processing space 30 with the inner cylinder 8a attached to the inner side of the outer cylinder 7c, and then the inner cylinder 8a is retracted and discharged. A chemical solution for removing the polymer layer may be supplied from the nozzle 22 to the processing space 20.
[0076]
In addition, when the polymer layer and the metal deposit are attached at the same time, it is not always necessary to first dissolve and remove the polymer layer as described above. You may carry out prior to a removal process.
[0077]
Furthermore, as shown in the following 1-4, the step of dissolving and removing the polymer layer and the step of dissolving and removing the metal deposit may be alternately performed so that at least one of the steps is performed a plurality of times. . This makes it possible to more reliably remove the polymer layer and the Cu deposit from a state where the polymer layer and the Cu deposit are mixed in a complicated manner.
1. Polymer layer removal-Metal deposit removal-Polymer layer removal
2. Metal deposit removal-Polymer layer removal-Metal deposit removal
3. Polymer layer removal-metal deposit removal as a set, repeated twice or more
4). Metal deposit removal-Polymer layer removal as a set, repeated twice or more
[0078]
As described above, the step of dissolving and removing the polymer layer can be performed in an inert atmosphere, and the step of dissolving and removing the metal deposit can be performed in an atmosphere in which a trace amount of oxygen-containing gas is added to an inert gas. When these steps are alternately performed as described above, the two types of atmospheres may be switched, but the present invention is not limited to this.
[0079]
According to the analysis results of the present inventors, it has been found that there are cases where a plurality of metal deposits attached to the substrate have different oxygen contents. For example, Cu deposits may include Cu-rich deposits and CuO-rich deposits. Since the state of the metal deposit is closely related to the progress of the etching process, the Cu-rich deposit is mainly used near the surface, and the CuO-rich deposit is mainly used inside. The property of the deposit may change depending on the distance from the surface of the object to be removed.
[0080]
A large amount of oxygen is required to completely oxidize the Cu-rich deposit, but a small amount of oxygen is required for the CuO-rich deposit. Since it is desirable to minimize the amount of oxygen added to the inert gas from the viewpoint of protecting the Cu wiring layer, when there are Cu-rich deposits and CuO-rich deposits as described above, For example, it is preferable to perform the dissolution removal process according to the following description and the procedures (a) to (e) shown in FIG.
(A) Inert gas atmosphere (N₂3 minutes to dissolve and remove the polymer layer in the atmosphere)
(B) 1 minute removal of Cu-rich deposits in an inert gas atmosphere containing 200 ppm oxygen
(C) 3 minutes to dissolve and remove the polymer layer in an inert gas atmosphere
(D) Dissolving and removing CuO-rich deposits in an inert gas atmosphere containing 100 ppm of oxygen for 1 minute
(E) 3 minutes to dissolve and remove the polymer layer in an inert gas atmosphere
By performing the dissolution removal process in such a procedure, it is possible to remove the metal deposit and the polymer layer while further reducing damage to the Cu wiring layer.
[0081]
The above shows the case where the Cu layer adhered together with the polymer layer is removed after the etching. However, in the semiconductor device manufacturing, there is a step of applying Cu plating to the surface of the wafer, and as shown in FIG. Although the plating layer 81 is formed, a Cu deposit 82 may be formed on the back surface or the like of the wafer W at that time. Also in this case, by using the apparatus shown in FIGS. 1 to 3, the processing space 30 is set to an inert gas atmosphere containing a predetermined concentration of oxygen, and a chemical solution is supplied to perform the same processing as in the previous embodiment, thereby performing plating. The Cu deposit 82 can be removed without damaging the layer 81.
[0082]
Next, another embodiment of the present invention will be described. Here, unlike the batch processing described above, an example of single wafer processing is shown. FIG. 15 is a view showing a single wafer type substrate processing apparatus. The substrate processing apparatus 101 has a chamber 102 for containing a wafer W, and an upper opening of the chamber 102 can be sealed with a lid 103, thereby forming a sealed processing space 110 in the chamber 102. It has become so.
[0083]
A holding member 104 that horizontally and rotatably supports the wafer W from the outside is provided in the chamber 102, and the holding member 104 is rotated by a motor 105.
[0084]
A discharge nozzle 106 is arranged vertically above the wafer W in the processing space 110. From the discharge nozzle 106, various chemicals, pure water, IPA, N supplied from a supply source (not shown)₂Gas and various chemicals can be discharged through the pipe 107.
[0085]
The bottom wall of the chamber 102 is provided with a drain port 111 that discharges used chemical liquid, pure water, and IPA, and an exhaust port 112 that exhausts the processing space 110. The drain port 111 and the exhaust port 112 include The drainage pipe 113 and the exhaust pipe 114 are connected to each other.
[0086]
On the side wall of the chamber 102, there is N in the processing space 110.₂Inert gas introduction port 121 for introducing an inert gas such as gas or Ar gas and O₂Gas, air, ozone (O₃) And the like, an oxygen-containing gas introduction port 122 for introducing an oxygen-containing gas is provided. An inert gas supply pipe 123 is connected to the inert gas introduction port 121, and an inert gas is supplied from the inert gas supply source 124 to the processing space 110 through the inert gas supply pipe 123. An oxygen-containing gas supply pipe 126 is connected to the oxygen-containing gas introduction port 122, and the oxygen-containing gas is supplied from the oxygen-containing gas supply source 127 through the oxygen-containing gas supply pipe 126 to the processing space 110. Heaters 124a and 127a are attached to the inert gas supply source 124 and the oxygen-containing gas supply source 127, respectively, and the inert gas and the oxygen-containing gas introduced into the processing space 110 are heated by the heaters 124a and 127a. Thus, by increasing the temperature in the chamber, it is possible to promote the dissolution reaction by the chemical solution. The inert gas supply pipe 123 and the oxygen-containing gas supply pipe 126 are provided with mass flow controllers 125 and 128, respectively, by which the flow rates of the inert gas and the oxygen-containing gas are controlled, and the atmosphere in the processing space 110 is controlled. Is adjustable. The flow rates of these mass flow controllers 125 and 128 are controlled by the controller 130. A flow meter may be provided instead of the mass flow controller, and the flow rate may be adjusted manually.
[0087]
When the substrate processing apparatus 101 configured as described above processes the wafer W in the state shown in FIG. 11D, first, the holding member is held by a transfer unit (not shown) with the lid 103 opened. After the wafer is sucked and held on 104 and the transfer means is retracted, the lid 103 is attached to form a sealed processing space 110.
[0088]
Next, from the viewpoint of preventing oxidation of the Cu wiring layer 71 as much as possible, an inert gas is supplied from the inert gas supply source 124 to the processing space 110 via the inert gas supply pipe 123 and the inert gas introduction port 121. The processing space 110 is an inert gas atmosphere that does not substantially contain oxygen.
[0089]
Thereafter, the holding member 104 is rotated at a predetermined speed by rotational driving by the motor 105, and a predetermined chemical solution (treatment liquid) is discharged from the discharge nozzle 106 to remove the resist mask and the polymer layer.
[0090]
In removing the resist mask and the polymer layer, first, a predetermined chemical solution is discharged from the discharge nozzle 106 for several tens of seconds. At this time, the discharged chemical solution is diffused on the surface of the wafer W by rotating the wafer W together with the holding member 104 at a predetermined speed. In this case, by controlling the rotation speed of the holding member 104 according to the viscosity of the chemical solution, the chemical solution can be uniformly diffused on the surface of the wafer W, and the resist mask and the polymer layer can be uniformly dissolved. it can.
[0091]
When the resist mask and the polymer layer are dissolved in this way, the chemical solution that has undergone dissolution reaction will stay on the surface of the wafer W. Since the reaction rate of the dissolved chemical solution is low, when such dissolved chemical solution stays, the discharge of the chemical solution is temporarily stopped, and the heated inert gas is discharged from the discharge nozzle 106 for about several seconds. At the same time, the output of the motor 105 is increased to increase the rotation speed of the holding member 104. Thereby, the chemical solution after the dissolution reaction is removed from the wafer W by the supply pressure of the inert gas and the centrifugal force generated by the rotation of the holding member 104. At this time, in order to effectively remove the dissolved chemical solution, the rotation speed of the holding member 104 is preferably controlled according to the viscosity of the chemical solution.
[0092]
After the chemical solution that has been dissolved and reacted is removed from the surface of the wafer W in this way, the rotation speed of the holding member 104 is restored, and a new chemical solution is discharged from the discharge nozzle 106. The process of supplying the chemical solution and the process of removing the dissolved chemical solution are repeated several times to several thousand times, thereby constantly supplying a new highly reactive chemical solution to the surface of the wafer W. The resist mask and the polymer layer can be efficiently removed.
[0093]
Next, after removing the resist mask and the polymer layer in this manner, N from the inert gas supply source 124 is removed.₂In a state in which the gas supply is continued, an oxygen-containing gas is supplied from the oxygen-containing gas supply source 127 to the processing space 110 through the oxygen-containing gas supply pipe 126 and the oxygen-containing gas introduction port 122, and the processing space 110 is supplied with predetermined oxygen. Concentration N₂The atmosphere. In this case, the oxygen concentration is controlled by controlling the mass flow controllers 125 and 128 by the controller 130, for example, so as to set them to a predetermined flow rate.
[0094]
After controlling the atmosphere in the processing space 110 as described above, the chemical solution is discharged from the discharge nozzle 106 in a state where the holding member 104 is rotated in the same manner as in the conventional resist mask and polymer layer removal processing. At this time, since the Cu deposit is oxidized by the oxygen in the atmosphere to become CuO, the oxidized CuO deposit is dissolved and removed by the supplied chemical solution, as shown in FIG. . In this case, it is preferable to control the oxygen concentration in accordance with the adhesion state of the Cu deposit 77 and so as not to damage the Cu wiring layer 71 as much as possible. The appropriate oxygen concentration at this time varies depending on the state of Cu deposits, etc., but is set to a predetermined concentration of, for example, about 5% or less. In this case, the oxygen concentration can be controlled by switching the gas itself in addition to the concentration control of the oxygen-containing gas itself. For example, air and O₂Gas switching or the like can be considered.
[0095]
In this way, when removing the Cu deposit 77, after the chemical solution is discharged for a predetermined time, the dissolved chemical solution is removed from the surface of the wafer W by discharging the inert gas and increasing the rotation speed of the holding member 104. By repeating this step several times to several thousand times, Cu deposits can be efficiently removed. This method is more effective because Cu deposits exposed when the chemical solution is shaken off can be oxidized by oxygen in the atmosphere.
[0096]
After removing the Cu deposit 77 in this manner, the supply of the oxygen-containing gas is stopped, the inside of the processing space 110 is again made an inert gas atmosphere substantially free of oxygen, and the previous resist mask and polymer layer are removed. In exactly the same manner as the treatment, the remaining polymer layer 76 is removed while preventing the oxidation of the Cu wiring layer 71 by repeatedly performing the chemical supply and the chemical removal after the dissolution reaction, and the state shown in FIG. It can be.
[0097]
After the resist mask, polymer layer, and Cu deposit removal process is completed, IPA or pure water is discharged from the discharge nozzle 106 to wash away the remaining reaction product from the wafer W. Then, pure water is discharged from the discharge nozzle 106 to rinse the wafer W, and finally the wafer W is rotated at a high speed together with the holding member 104 to spin dry the wafer W.
[0098]
As described above, also in this embodiment, when removing Cu deposits, a small amount of oxygen-containing gas is added to the inert gas atmosphere. Therefore, the minimum amount necessary to oxidize and remove Cu deposits. In addition, when removing the resist mask and polymer layer in an atmosphere that does not substantially contain oxygen, oxidation of the Cu wiring layer is prevented as much as possible, and the Cu wiring layer is almost dissolved and removed. Without doing so, damage to the Cu wiring layer can be reduced, and the resist mask, polymer layer, and Cu deposits can be removed.
[0099]
In such a single wafer type substrate processing apparatus, instead of removing the resist mask and the polymer layer at the same time, they may be removed in different steps using different chemical solutions. In this case, for example, the resist mask removing chemical solution may be first supplied from the discharge nozzle 106 to remove the resist mask, and then the polymer layer removing chemical solution may be supplied from the discharge nozzle 106.
[0100]
Further, as in the previous embodiment, when the polymer layer and the metal deposit are attached at the same time, it is not always necessary to first dissolve and remove the polymer layer as described above. The removal step may be performed prior to the dissolution removal step of the polymer layer.
[0101]
Furthermore, as shown in the following 1-4, the step of dissolving and removing the polymer layer and the step of dissolving and removing the metal deposit may be alternately performed so that at least one of the steps is performed a plurality of times. .
1. Polymer layer removal-Metal deposit removal-Polymer layer removal
2. Metal deposit removal-Polymer layer removal-Metal deposit removal
3. Polymer layer removal-metal deposit removal as a set, repeated twice or more
4). Metal deposit removal-Polymer layer removal as a set, repeated twice or more
[0102]
Furthermore, when there is a Cu-rich deposit near the surface of the deposit and a CuO-rich deposit is present inside the deposit, the deposit is dissolved in the same manner as in the previous embodiment. Can be removed.
[0103]
Such a single wafer processing apparatus can also be applied to the processing of the wafer after Cu plating shown in FIG. In this case, the wafer W is held by the holding member 104 with its back surface facing up, the processing space 110 is set to an inert gas atmosphere containing a predetermined concentration of oxygen, and a chemical solution is supplied to perform the same processing. By doing so, the Cu deposit 82 can be removed without damaging the plating layer 81. In this case, from the viewpoint of further reducing damage to the plating layer 81, it is preferable that only the portion of the wafer W on which the plating layer 81 is formed by means such as providing a partition wall be in an atmosphere having a low oxygen concentration. Further, in this case, since there is a space below the holding member 104, a discharge nozzle can be provided in that space. Therefore, even if the wafer W is held with its surface facing up, the plating layer 81 Cu deposits can be removed without causing damage.
[0104]
In addition, this invention is not limited to the said embodiment, A various deformation | transformation is possible. For example, in the above-described embodiment, the case of removing Cu deposits has been described. However, any metal whose solubility is changed by oxidation can be dissolved and removed by the same mechanism. Such metals include Ru and Pt.
[0105]
In the above embodiment, oxygen is supplied by introducing an oxygen-containing gas into an inert gas atmosphere. However, the present invention is not limited thereto, and oxygen is dissolved in a chemical solution supplied as a processing solution, so that the chemical solution and oxygen are simultaneously mixed. You may supply. Also in this case, if the amount of dissolved oxygen is controlled, the minimum amount of oxygen necessary to oxidize and remove the metal deposit can be reduced, and the metal layer is prevented from being oxidized as much as possible. The kimono can be removed.
[0106]
Furthermore, although the case where both the resist mask and the polymer layer are removed with a chemical solution (treatment solution) has been shown, the present invention can also be applied to the case where the polymer layer is removed after the resist mask is removed by dry ashing. Furthermore, although the case where it applied to a semiconductor wafer was shown, it is not restricted to this, It can apply also to processing of other board | substrates, such as a board | substrate for liquid crystal display devices (LCD).
[0108]
【The invention's effect】
  As explained above, according to the present invention,When the polymer layer and metal deposits attached to the substrate having the metal layer are removed by the treatment liquid, specifically, at least the metal layer and the insulating layer thereon are formed on the substrate, and the insulating layer reaches the metal layer. When the polymer layer remaining after etching until the metal layer and the metal layer existing inside the polymer layer are sputtered and adhered, or in addition to these, the resist mask is removed by the treatment liquid, an inert gas is introduced into the chamber. After introducing an inert gas atmosphere inside the chamber, a processing solution is supplied into the chamber to remove the polymer layer or resist mask and polymer layer, and an inert gas and an oxygen-containing gas are introduced into the chamber. Inside the chamberIt is possible to oxidize the metal depositOxygen concentrationInert gasSince the processing solution is supplied into the chamber after the atmosphere has been set up and the deposits oxidized by oxygen in the chamber atmosphere are dissolved and removed, the metal deposits are oxidized and removed when the metal deposits are removed. The minimum amount of oxygen necessary to enable the removal of the polymer layer or the resist mask and the polymer layer is performed in an atmosphere substantially free of oxygen gas, so that the metal layer is oxidized. As much as possible, metal deposits can be removed without causing damage to the metal layer by the treatment liquid.
[0109]
  Furthermore, an inert gas introduction means for introducing an inert gas into the chamber; an oxygen gas introduction means for introducing an oxygen-containing gas into the chamber;A first treatment liquid introduction means for introducing a first treatment liquid for removing the polymer layer attached to the substrate in the chamber;HSecond treatment liquid introduction means for introducing a second treatment liquid for removing metal deposits adhering to the substrate in the chamber;Provided,When removing the polymer layer, an inert gas is introduced into the chamber to make the chamber an inert gas atmosphere, and the first treatment liquid is supplied into the chamber to remove metal deposits. Introducing an inert gas and an oxygen-containing gas into the chamber so that the inside of the chamber is an inert gas atmosphere having an oxygen concentration that can oxidize the metal deposit, and the second treatment is performed in the chamber. Supply liquidSoWhen removing metal deposits, the minimum amount of oxygen necessary to oxidize and remove the metal deposits can be obtained, and when removing the polymer layer, oxygen gas is substantially contained. Since it is performed in a non-atmosphere, the metal deposit can be removed without causing the metal layer to be oxidized as much as possible and causing no damage to the metal layer by the treatment liquid.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a state in which an inner chamber is arranged inside an outer chamber of a substrate processing apparatus according to an embodiment used for carrying out the method of the present invention.
FIG. 2 is a cross-sectional view showing a state where an inner chamber of a substrate processing apparatus according to an embodiment used for carrying out the method of the present invention is brought out of an outer chamber.
3 is a cross-sectional view taken along line AA of the substrate processing apparatus of FIG.
4 is a perspective view showing a rotor of the substrate processing apparatus of FIG. 1. FIG.
FIG. 5 is an exploded perspective view showing a main part of a switching member for switching a holding mechanism of a rotor between a holding state and a released state and a vertical wall on the motor side.
FIG. 6 is a perspective view showing a state of the switching member and the protrusion when the holding mechanism is in a released state.
FIG. 7 is a perspective view showing a state of the switching member and the protrusion when the holding mechanism is in a holding state.
8 is a perspective view showing an arm, a balance weight, and a protrusion of the rotor shown in FIG. 4. FIG.
9 is an enlarged cross-sectional view of a switching mechanism and its peripheral part of the substrate processing apparatus of FIG.
10 is an enlarged cross-sectional view of a sealing mechanism and its peripheral part of the substrate processing apparatus of FIG. 1;
FIG. 11 is a cross-sectional view showing a manufacturing process of a semiconductor device to which a substrate processing method according to an embodiment of the present invention is applied.
FIG. 12 is a cross-sectional view for explaining a processing step of the substrate processing method according to one embodiment of the present invention.
FIG. 13 is a graph showing the relationship between processing time and oxygen concentration in a processing procedure for removing a plurality of types of Cu deposits to which a substrate processing method according to an embodiment of the present invention is applied.
FIG. 14 is a cross-sectional view showing a semiconductor wafer applied to a substrate processing method according to another embodiment of the present invention.
FIG. 15 is a sectional view showing a substrate processing apparatus according to another embodiment used for carrying out the method of the present invention.
[Explanation of symbols]
1,101 …… Substrate processing equipment
5 …… Rotor
7, 8, 102 ... Chamber
20, 30, 110 ... processing space
22, 32, 106 ... discharge nozzle
51, 121 …… Inert gas introduction port
52,122 ... Oxygen-containing gas introduction port
54,124 ... inert gas supply source
57,127 …… Oxygen-containing gas supply source
55, 58, 125, 128 ... Mass flow controller
60, 130 ... Controller
71 …… Cu wiring layer
72 …… SiN barrier layer
73 …… Interlayer insulation layer
74 …… Resist layer (resist mask)
75 …… Contact hole
76,78 …… Polymer layer
77 …… Cu deposit (metal deposit)
W …… Semiconductor wafer (substrate)

Claims (16)

A substrate processing method for removing a polymer layer and metal deposits attached to a substrate having a metal layer with a processing liquid,
Loading the substrate into the chamber;
A step of introducing an inert gas into the chamber to the chamber in an inert gas atmosphere to dissolve and remove the polymer layer by supplying a process liquid into the chamber,
Wherein by introducing an inert gas and an oxygen-containing gas into the chamber, the chamber in the inert gas atmosphere having an oxygen concentration of the degree capable of oxidizing the metal deposit, supplying the processing liquid into the chamber And a step of dissolving and removing deposits oxidized by oxygen in the atmosphere in the chamber. Process, the substrate processing method according to claim 1, characterized in that after the step of dissolving and removing the polymer layer is dissolved and removed the deposits. Process, the substrate processing method according to claim 1, characterized in that before the step of dissolving and removing the polymer layer is dissolved and removed the deposits. Alternating a step of dissolving and removing step and the deposits are dissolved removing the polymer layer, any one of claim 1, wherein according to claim 3 that is repeated so that at least one of the process becomes more times 1 The substrate processing method according to item. At least a metal layer and an insulating layer on the substrate are formed on the substrate, the polymer layer remaining after etching the insulating layer until reaching the metal layer and the metal deposit on which the metal layer is sputtered and adhered A substrate processing method for removing the substrate with a processing solution,
Loading the etched substrate into the chamber;
Wherein by introducing an inert gas into the chamber to the chamber in an inert gas atmosphere, the polymer layer dissolved is removed by supplying a processing liquid into said chamber, thereby exposing the metal deposit,
Thereafter, the by introducing oxygen-containing gas into the chamber, the chamber in the inert gas atmosphere having an oxygen concentration of the degree capable of oxidizing the metal deposit, by supplying the processing liquid into the chamber, Dissolving and removing exposed deposits oxidized by oxygen in the chamber atmosphere;
Thereafter, to stop the supply of oxygen-containing gas, wherein the chamber is an inert gas atmosphere, characterized by comprising the step of dissolving and removing the polymer layer remaining by supplying the processing liquid into the chamber again Substrate processing method. A resist mask, a polymer layer, and a metal layer existing inside the polymer layer are formed after forming at least a metal layer and an insulating layer thereover on the substrate and etching the insulating layer until the metal layer is etched using the photoresist layer as a mask. A substrate processing method for removing metal deposits deposited by sputtering with a processing solution,
Loading the etched substrate into the chamber;
The chamber an inert gas atmosphere by introducing an inert gas into the chamber and removing dissolve the resist mask by supplying the processing liquid into the chamber,
Thereby dissolving and removing the polymer layer by supplying a process liquid into the chamber of an inert gas atmosphere, a step of exposing the polymer layer inside the metal deposit,
Thereafter, the by introducing oxygen-containing gas into the chamber, the chamber in the inert gas atmosphere having an oxygen concentration of the degree capable of oxidizing the metal deposit, by supplying the processing liquid into the chamber, Dissolving and removing exposed deposits oxidized by oxygen in the chamber atmosphere;
Thereafter, to stop the supply of oxygen-containing gas, again in the chamber in an inert gas atmosphere, characterized by comprising the step of dissolving and removing the polymer layer remaining by supplying the processing liquid into the chamber substrate Processing method. 7. The substrate processing method according to claim 6 , wherein the step of dissolving and removing the resist mask and the step of dissolving and removing the polymer layer and exposing the metal deposit inside the polymer layer are simultaneously performed. A step of dissolving and removing the polymer layer step and residual dissolving and removing the deposits are alternately one of claims 5 to claim 7, characterized in that repeated so that at least one of the steps is a plurality of times The substrate processing method according to claim 1. Dissolving and removing the polymer layer, the substrate processing according to any one of claims 1 to 8, characterized in that it is made by repeating the removal of the processing fluid from the supply and the substrate of the treatment liquid Method. The resist dissolution removal of the mask, the substrate processing method according to claim 6 or claim 7 characterized in that it is made by repeating the processing liquid removal from the feed and the substrate of the processing solution. When oxidizing the metal deposit, the substrate processing method as claimed in any one of claims 10, characterized in that controlling the oxygen concentration in the chamber in accordance with the state of adhesion of the metal deposit. The substrate processing method as claimed in any one of claims 11 wherein the metal deposits, characterized in that it is mainly formed of at least one Cu, Ru and Pt. A first deposit made of a polymer attached to a substrate having a metal layer, a second deposit containing a metal, and a third deposit containing a metal and having a composition different from that of the second deposit A substrate processing method for removing the substrate with a processing solution,
  Loading the substrate into the chamber;
  Introducing an inert gas into the chamber to make the chamber an inert gas atmosphere, supplying a treatment liquid into the chamber to dissolve and remove the first deposit made of polymer;
  An inert gas and an oxygen-containing gas are introduced into the chamber so that the inside of the chamber has an inert gas atmosphere having an oxygen concentration that can oxidize the second deposit, and a treatment liquid is contained in the chamber. And dissolving and removing the second deposit oxidized by oxygen in the atmosphere in the chamber;
  An inert gas and an oxygen-containing gas are introduced into the chamber so that the inside of the chamber has an inert gas atmosphere having an oxygen concentration that can oxidize the third deposit, and a treatment liquid is contained in the chamber. And dissolving and removing the third deposit oxidized by oxygen in the atmosphere in the chamber;
The substrate processing method characterized by comprising. The substrate processing apparatus for removing the treatment solution and the polymer layer deposited on the substrate and the metal deposit having a metal layer,
A chamber for housing the substrate;
An inert gas introduction means for introducing an inert gas into the chamber;
Oxygen gas introducing means for introducing oxygen-containing gas into the chamber;
An exhaust means for exhausting the chamber;
First treatment liquid introduction means for introducing a first treatment liquid for removing the polymer layer attached to the substrate in the chamber;
And second treatment liquid introduction means for introducing a second treatment liquid to remove metal deposits adhered to the substrate in a chamber,
A drainage means for draining the processing liquid supplied into the chamber ;
When removing the polymer layer, an inert gas is introduced into the chamber to make the chamber an inert gas atmosphere, and a first treatment liquid is supplied into the chamber.
When removing the metal deposit, an inert gas and an oxygen-containing gas are introduced into the chamber so that the inside of the chamber has an inert gas atmosphere with an oxygen concentration sufficient to oxidize the metal deposit. A substrate processing apparatus , wherein a second processing liquid is supplied into the chamber . 15. The substrate processing apparatus according to claim 14 , wherein at least one of the inert gas introducing unit and the oxygen gas introducing unit has a flow rate adjusting mechanism. 16. The substrate processing apparatus according to claim 14 , further comprising substrate holding means for rotatably holding the substrate accommodated in the chamber.

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