JP2010027786A - Substrate treatment method, substrate-treating device, and storage medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate treatment method capable of reliably removing an etching residue or an ashing residue remaining on the surface of a prescribed film after plasma etching without damaging the film. <P>SOLUTION: The substrate treatment method removes an etching residue remaining on the surface of a prescribed film after performing dry etching to a substrate, or an ashing residue remaining on the surface of the film after ashing the etching residue. The substrate treatment method includes: a first process for forming a liquid-like organic acid on the surface of the substrate, decomposing a CF polymer by the liquid-like organic acid, and dissolving the decomposed material into the liquid-like organic acid; and a second process for annealing the substrate after that, and vaporizing the organic acid and the dissolved material of the CF polymer dissolved to the organic acid for removing from the substrate. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention is a process for removing etching residues remaining on the surface of a predetermined film after performing dry etching on a substrate such as a semiconductor wafer, or removing ashing residues remaining on the surface of the film after ashing the etching residue. The present invention relates to a substrate processing method, a substrate processing apparatus, and a storage medium.

  Recently, in response to demands for higher speeds of semiconductor devices, finer wiring patterns, and higher integration, there has been a demand for lower capacitance between wirings, improved wiring conductivity, and improved electromigration resistance. As a corresponding technology, copper (Cu), which has higher conductivity than aluminum (Al) and tungsten (W) and has excellent electromigration resistance, is used as a wiring material, and a low dielectric constant film (Low-k) is used as an interlayer insulating film. Cu multilayer wiring technology using a film) has attracted attention.

  In such a technique, a low-k film as an interlayer insulating film is etched to form holes and trenches, and Cu, which is a wiring material, is embedded therein, but when the low-k film is etched, A single wafer type plasma etching process is performed in which etching is performed by plasma using a resist as a mask.

  Since a CF-based gas is often used as an etching gas for plasma etching of a low-k film, a CF polymer is used as an etching residue in addition to a resist residue on the sidewall or bottom of a hole or trench formed by etching. Adhere to.

  Not only such low-k film etching, but also etching residues containing CF polymer produced by etching with resist residues and CF-based gas are generally removed by ashing. Therefore, the resist residue and the CF polymer often remain as an ashing residue after ashing. In order to remove these resist residues and CF polymer, wet cleaning with a chemical solution is often performed after ashing.

  However, in general wet cleaning, rinsing with pure water is performed after chemical cleaning, and when the resist residue and CF polymer adhering to the low-k film are removed by wet cleaning, the low-k film absorbs moisture. There is a risk of taking damage.

  As a technique for removing resist residues and CF polymer without damaging the Low-k film, dry cleaning using an organic acid vapor has been studied (Patent Documents 1 and 2). However, in practice, it is difficult to sufficiently remove the resist residue and the CF-based polymer by dry cleaning using an organic acid vapor.

On the other hand, Non-Patent Document 1 discloses a technique for removing a resist by condensing acetic acid vapor on a substrate, and this method can also be applied to removing an etching residue or an ashing residue containing a resist residue and a CF polymer. there is a possibility. However, in this technique, acetic acid vapor is condensed on the substrate to alter the resist, and then washed with water. When applied to a low-k film, damage due to moisture absorption is the same as in wet cleaning. Concerned.
JP 2006-216937 A JP 2006-286802 A S. Noda et al., J. Electrochem. Soc. 152 (1) G73 (2005)

  The present invention has been made in view of such circumstances, and etching residue remaining on the surface of a predetermined film after plasma etching or ashing residue remaining on the surface of the film after ashing the etching residue is added to the film. It is an object of the present invention to provide a substrate processing method and a substrate processing apparatus that can be reliably removed without causing damage. It is another object of the present invention to provide a storage medium storing a program for executing such a substrate processing method.

  In order to solve the above problems, in the first aspect of the present invention, the etching residue remaining on the surface of a predetermined film after performing dry etching on the substrate, or remaining on the surface of the film after ashing the etching residue and the resist. A substrate processing method for removing an ashing residue, wherein a liquid organic acid is formed on a substrate surface, the etching residue or ashing residue is decomposed by the liquid organic acid, and the decomposition product is converted into a liquid organic acid. And a second step of annealing the substrate to vaporize and remove the organic acid and the dissolved ashing residue dissolved in the organic acid from the substrate. A substrate processing method is provided.

  In the first aspect, the etching residue or ashing residue may include at least one of a resist residue and a CF polymer. The substrate includes a Cu wiring layer, and a cap film and a Low-k film formed thereon, and the cap film and the Low-k film are plasma etched up to the Cu wiring layer, or thereafter Further, ashing is performed, and at least the etching residue or the ashing residue attached to the Low-k film can be used. In this case, the etching residue or ashing residue can be at least one of a resist residue, a CF polymer, and copper oxide.

  In the first step, the substrate is placed on a mounting table provided in the processing chamber, and the organic acid vapor is introduced into the processing chamber in a state where the processing chamber is evacuated, and the organic acid vapor is condensed on the substrate surface. By doing so, a liquid organic acid can be formed on the substrate surface. In the second step, the substrate subjected to the first step is placed on a mounting table provided in the processing chamber, the substrate is evacuated, and the substrate is heated in a non-oxidizing atmosphere. Can be performed. In this case, it is preferable that the first step and the second step are performed without breaking the vacuum.

  In order to perform the first step and the second step without breaking the vacuum, a first processing unit that performs the first step, a second processing unit that performs the second step, and the first step A first processing unit is provided on the substrate in the first processing unit using a processing apparatus having a transfer device connected to the processing unit and the second processing unit, including a transfer device for transferring the substrate, and having a transfer chamber held in a vacuum. Then, the substrate can be transported to the second processing unit by the transport device, and the second process can be performed on the substrate by the second processing unit. Further, the first process and the second process may be performed in the same processing unit.

  The organic acid is preferably a carboxylic acid, and more preferably formic acid.

  When the organic acid is formic acid, the first step is to place the substrate on a mounting table provided in the processing chamber, and bring the liquid formic acid to 25 to 100 ° C. in a state where the processing chamber is evacuated. The formic acid vapor is formed by heating, the formic acid vapor is introduced into the processing chamber, and the substrate is maintained at a temperature of 8 ° C. (freezing point of formic acid) or more and 5 ° C. or less lower than the heating temperature. In the second step, the formic acid and the formic acid can be formed by heating the substrate on which the first step has been performed to 150 to 300 ° C. Etching residue or ashing residue dissolved in formic acid can be vaporized.

  In the second aspect of the present invention, the substrate having a Cu wiring layer and a cap film and a Low-k film formed thereon is compatible with the Cu wiring layer of the cap film and the Low-k film. A step of plasma etching the portion to be etched, a step of removing the etching residue and resist of the etching by ashing, and after ashing, a liquid organic acid is formed on the surface of the Low-k film to which the ashing residue adheres, Decomposing the ashing residue with an organic acid and dissolving the decomposition product in a liquid organic acid, and then annealing the substrate to vaporize the ashing residue dissolved in the organic acid and the organic acid. A barrier layer in the hole or trench reaching the exposed Cu wiring formed by the dry etching Forming, and forming a Cu seed layer over the barrier layer, to provide a substrate processing method which comprises carrying out without all of these steps to break the vacuum.

  In the third aspect of the present invention, a substrate having an etching residue remaining on the surface of a predetermined film after dry etching, or an ashing residue remaining on the surface of the film after ashing the etching residue and resist is carried in. A processing chamber capable of maintaining a vacuum; a mounting table provided in the processing chamber for mounting a substrate; an organic acid vapor supply mechanism for supplying an organic acid vapor into the processing chamber; and the substrate on the mounting table. A first processing unit having a temperature control mechanism for adjusting the temperature of the substrate to a temperature lower than the temperature of the organic acid vapor, and a process in which a substrate after processing in the first processing unit is carried in and can be maintained in a vacuum A second processing unit having a chamber, a mounting table on which the substrate is mounted, and a heating mechanism for heating the substrate on the mounting table. The substrate having the etching residue or the ashing residue is carried into the laboratory, the organic acid vapor is supplied from the organic acid supply mechanism to the processing chamber, and the temperature of the substrate is lower than the temperature of the organic acid vapor by the temperature control mechanism. The organic acid is condensed on the surface of the substrate and the liquid organic acid is formed on the surface of the substrate. The liquid organic acid decomposes the etching residue or the ashing residue and the liquid organic acid. Etching residue in which the decomposition product is dissolved in the acid, the substrate on which the liquid organic acid is formed is carried into the processing chamber of the second processing unit, heated by the heating mechanism, and dissolved in the organic acid and the organic acid Alternatively, a substrate processing apparatus is provided, in which a ashing residue melt is vaporized and removed from a substrate.

  In the third aspect, the first processing unit and the second processing unit are connected to each other, further including a transfer device that transfers the substrate, further including a transfer chamber held in a vacuum, and the first process. It is preferable that the processing by the unit and the processing by the second processing unit are performed without breaking the vacuum.

  In the fourth aspect of the present invention, a substrate having an etching residue remaining on the surface of a predetermined film after dry etching or an ashing residue remaining on the surface of the film after ashing the etching residue and resist is carried in. A processing chamber capable of maintaining a vacuum; a mounting table provided in the processing chamber for mounting a substrate; an organic acid vapor supply mechanism for supplying an organic acid vapor into the processing chamber; and the substrate on the mounting table. And a heating mechanism for heating the substrate on the mounting table, the processing chamber having the etching residue or the ashing residue. The substrate is carried in, the organic acid vapor is supplied from the organic acid supply mechanism to the processing chamber, and the temperature of the substrate is adjusted to a temperature lower than the temperature of the organic acid vapor by the temperature adjustment mechanism. When the organic acid is condensed on the substrate surface, a liquid organic acid is formed on the substrate surface, and the etching residue or the ashing residue is decomposed by the liquid organic acid and decomposed into a liquid organic acid. A substrate processing apparatus, wherein an object is dissolved, the substrate is heated by the heating mechanism, and the etching residue or the ashing residue dissolved in the organic acid is vaporized and removed from the substrate. provide.

  According to a fifth aspect of the present invention, there are provided a plurality of substrates having an etching residue remaining on the surface of a predetermined film after dry etching, or an ashing residue remaining on the surface of the film after ashing the etching residue and the resist. A processing vessel that is carried in and can be held in vacuum, a substrate holding member that holds a plurality of substrates in the processing vessel, an organic acid vapor supply mechanism that supplies organic acid vapor into the processing vessel, and a holding member A temperature adjustment mechanism for adjusting the temperature of the plurality of substrates held to a temperature lower than the temperature of the organic acid vapor; and a heating mechanism for heating the plurality of substrates held by the holding member, A substrate having the etching residue or ashing residue is carried into a container, and an organic acid vapor is supplied from the organic acid supply mechanism to the processing container. Is adjusted to a temperature lower than the temperature of the organic acid vapor to cause condensation of the organic acid on the substrate surface, thereby forming a liquid organic acid on the substrate surface, and the liquid organic acid causes the etching residue or The ashing residue is decomposed and the decomposition product is dissolved in a liquid organic acid, the substrates are heated by the heating mechanism, and the etching residue or the ashing residue solution dissolved in the organic acid and the organic acid is vaporized. The substrate processing apparatus is characterized by being removed from the substrate.

  In the third to fifth aspects, the etching residue or ashing residue may include at least one of a resist residue and a CF polymer. The substrate has a Cu wiring layer and a Low-k film formed thereon, and the Low-k film is plasma etched up to the Cu wiring layer, or is further ashed thereafter. The etching residue or the ashing residue can be used even if it adheres to the Low-k film. In this case, the etching residue or the ashing residue may include at least one of a resist residue, a CF polymer, and copper oxide.

  In a sixth aspect of the present invention, plasma etching is performed on a portion corresponding to the Cu wiring layer of the Low-k film on a substrate having a Cu wiring layer and a Low-k film formed thereon. An etching unit, an ashing unit that removes the etching residue and resist of the etching by ashing, and a liquid organic acid is formed on the surface of the low-k film to which the ashing residue adheres after ashing, and the liquid organic acid A dissolution unit that decomposes the ashing residue and dissolves the decomposition product in a liquid organic acid, and after the dissolution treatment in the dissolution unit, the substrate is annealed to remove the ashing residue dissolved in the organic acid and the organic acid. A vaporizing unit that vaporizes and removes the melt from the substrate; and a barrier layer forming unit for forming a barrier layer in a hole reaching the u wiring, a seed layer forming unit for forming a Cu seed layer on the barrier layer, the etching unit, the ashing unit, the melting unit, and the vaporizing unit The barrier layer forming unit, and the seed layer forming unit are connected to each other, and include a transfer device that transfers the substrate, and a transfer chamber that is held in vacuum, the etching unit, the ashing unit, the melting unit, Processing by the vaporization unit, the barrier layer forming unit, and the seed layer forming unit is performed in a vacuum, and the processing of all units is broken by performing the transfer between the units through the transfer chamber. Provided is a substrate processing apparatus which is characterized in that it is performed without any problem.

  According to a seventh aspect of the present invention, there is provided a storage medium that stores a program that operates on a computer and controls a processing device, and the program is a board according to the first aspect or the second aspect when executed. Provided is a storage medium characterized by causing a computer to control a processing device so that the processing method is performed.

  According to the present invention, a liquid organic acid is formed on the surface of the substrate, and the etching residue or ashing residue typically containing at least one of a resist residue and a CF polymer is decomposed and liquid by the liquid organic acid. Water or chemical solution by dissolving the decomposition product in the organic acid in the form of a liquid, and then annealing the substrate to vaporize and remove the organic acid and the dissolved ashing residue dissolved in the organic acid from the substrate. Etching residue or ashing residue can be removed with a liquid organic acid that is more reactive than organic acid vapor without using, so that etching residue or ashing residue can be reliably removed without damaging the substrate. be able to. Therefore, it is particularly effective when removing etching residues or ashing residues attached to the Low-k film after etching or ashing of the Low-k film which is easily damaged.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
Here, a case where a semiconductor wafer is used as the substrate to be processed will be described. FIG. 1 is a schematic configuration diagram showing an example of a substrate processing apparatus for carrying out the substrate processing method of the present invention.

The substrate processing apparatus includes a first processing unit 1 for processing a low-k film after plasma etching existing on the surface of a semiconductor wafer (hereinafter simply referred to as a wafer) as a substrate to be processed with a liquid organic acid, A second processing unit 2 is provided for performing an annealing process on the wafer after the processing in one processing unit 1, and these first and second processing units 1 and 2 are provided in two transfer chambers 5 having an octagonal shape. It is provided corresponding to each side. Load lock chambers 6 and 7 are provided on the other two sides of the transfer chamber 5, respectively. A load / unload chamber 8 is provided on the opposite side of the load lock chambers 6 and 7 from the transfer chamber 5, and a semiconductor wafer W as a substrate to be processed is provided on the opposite side of the load lock chambers 6 and 7 of the load / unload chamber 8. Are provided with ports 9, 10, and 11 for attaching three carriers C capable of accommodating the.

  The inside of the transfer chamber 5 and the first and second processing units 1 and 2 are held in a vacuum atmosphere, and the carry-in / out chamber 8 is held in an air atmosphere. The load lock chambers 6 and 7 can be switched between an air atmosphere and a vacuum atmosphere.

  As shown in the figure, the first and second processing units 1 and 2 are connected to each side of the transfer chamber 5 via a gate valve G, and these transfer chambers 5 are opened by opening the corresponding gate valve G. Is closed from the transfer chamber 5 by closing the corresponding gate valve G. The load lock chambers 6 and 7 are connected to corresponding sides of the transfer chamber 5 via the first gate valve G1, and are connected to the loading / unloading chamber 8 via the second gate valve G2. . The load lock chambers 6 and 7 are communicated with the transfer chamber 5 by opening the first gate valve G1, and are shut off from the transfer chamber by closing the first gate valve G1. The second gate valve G2 is opened to communicate with the loading / unloading chamber 8, and the second gate valve G2 is closed to shut off the loading / unloading chamber 8.

  In the transfer chamber 5, a transfer device 12 for loading and unloading the semiconductor wafer W with respect to the first and second processing units 1 and 2 and the load lock chambers 6 and 7 is provided. The transfer device 12 is disposed substantially in the center of the transfer chamber 5 and has two support arms 14a and 14b that support the wafer W at the tip of a rotatable / extensible / retractable portion 13 that can be rotated and extended. These two support arms 14a and 14b are attached to the rotation / extension / contraction section 13 so as to face in opposite directions.

  Three ports 9, 10, 11 for attaching a FOUP (Front Opening Unified Pod) which is a wafer storage container of the loading / unloading chamber 8 are provided with shutters (not shown), respectively. The wafer W is accommodated or directly attached with the empty hoop F placed on the stage S, and when attached, the shutter is released so as to communicate with the loading / unloading chamber 8 while preventing intrusion of outside air. It has become. An alignment chamber 15 is provided on the side surface of the loading / unloading chamber 8 where the semiconductor wafer W is aligned.

  In the loading / unloading chamber 8, a transfer device 16 for loading / unloading the semiconductor wafer W into / from the FOUP F and loading / unloading the semiconductor wafer W into / from the load lock chambers 6, 7 is provided. The transfer device 16 has an articulated arm structure, and can run on the rail 18 along the direction in which the hoops F are arranged. The semiconductor wafer W is placed on the support arm 17 at the tip of the transfer device 16. Transport.

  The processing apparatus includes a control unit 20, and the control unit 20 includes a process controller 21, a user interface 22, and a storage unit 23. The process controller 21 includes each component of the processing apparatus, for example, a drive system of the transfer device 12, a gas supply system of the first and second processing units 1 and 2, a transfer chamber 5, and the first and second processing units 1 and 2. The evacuation system of the load lock chambers 6 and 7, the drive system of the gate valve G, and the like are connected, and these are controlled by the process controller 21.

  The user interface 22 is connected to the process controller 21 and includes a keyboard on which an operator inputs commands to manage the processing apparatus, a display that visualizes and displays the operating status of the plasma processing apparatus, and the like.

  The storage unit 23 is connected to the process controller 21 and is stored in each component of the processing device according to a control program for realizing various processes executed by the processing device under the control of the process controller 21 and processing conditions. A program for executing the process, that is, a recipe is stored. The recipe is stored in a storage medium in the storage unit 23. The storage medium may be a fixed medium such as a hard disk or a portable medium such as a CDROM, DVD, or flash memory. Moreover, you may make it transmit a recipe suitably from another apparatus via a dedicated line, for example.

Then, if necessary, an arbitrary recipe is called from the storage unit 23 by an instruction from the user interface 21 and the process controller 2
1, the desired processing is performed in the processing device under the control of the process controller 21.

Next, the first processing unit 1 will be described.
FIG. 2 is a cross-sectional view showing a schematic configuration of the first processing unit 1. The first processing unit 1 includes a chamber 31 that can hold a wafer W and can be held in a vacuum, an organic acid supply mechanism 32 that supplies organic acid vapor into the chamber 31, and a chamber 31 that uses, for example, nitrogen gas or argon gas as a dilution gas. A dilution gas supply mechanism 33 for supplying the inside of the chamber 31 and an exhaust mechanism 34 for evacuating the chamber 31 are provided.

  A mounting table 35 for mounting the accommodated wafer W is provided at the bottom of the chamber 31. The mounting table 35 has a predetermined temperature as a temperature control mechanism for controlling the temperature of the wafer W. The temperature control medium flow path 36 through which the controlled temperature control medium flows is provided. A loading / unloading port 37 for loading / unloading the wafer W is formed on the side wall of the chamber 31, and the loading / unloading port 37 is opened and closed by a gate valve G.

  A shower head 40 is provided on the upper portion of the chamber 31 so as to face the mounting table 35. The shower head 40 has a diffusion space 41 for diffusing the organic acid supplied from the organic acid supply mechanism 32 and the dilution gas supplied from the dilution gas supply mechanism 33 inside, and has an organic surface on the surface facing the mounting table 35. A plurality of discharge holes 42 for discharging acid vapor or dilution gas into the chamber 31 are formed.

  An exhaust port 38 is formed in the bottom wall of the chamber 31. The exhaust mechanism 34 includes an exhaust pipe 46 connected to the exhaust port 38 and a vacuum pump 47 that exhausts the interior of the chamber 31 through the exhaust pipe 46. And a pressure adjusting valve 48 provided in the exhaust pipe 46.

  The organic acid supply mechanism 32 includes an organic acid reservoir 51 in which a liquid organic acid is stored, a heater 52 for vaporizing the organic acid in the organic acid reservoir 51, and a shower of the vaporized organic acid. An organic acid vapor supply line 53 guided into the diffusion space 41 of the head 40, a mass flow controller 54 as a flow rate adjusting mechanism for adjusting the flow rate of the organic acid vapor flowing through the organic acid vapor supply line 53, and the organic acid vapor supply line 53 And an open / close valve 55 for opening and closing the valve.

As the organic acid, a carboxylic acid can be preferably used. As the carboxylic acid, formic acid (HCOOH), acetic acid (CH ₃ COOH), propionic acid (CH ₃ CH ₂ COOH), butyric acid (CH ₃ (CH ₂ ) ₂ COOH), valeric acid (CH ₃ (CH ₂ ) ₃ COOH) Among these, formic acid (HCOOH), acetic acid (CH ₃ COOH), and propionic acid (CH ₃ CH ₂ COOH) are preferable, and formic acid (HCOOH) is particularly preferable.

  The dilution gas supply mechanism 33 includes a dilution gas supply source 56 for supplying a dilution gas, for example, nitrogen gas or argon gas, a dilution gas supply line 57 for introducing the dilution gas into the diffusion space 41 of the shower head 40, and a dilution gas supply line. A mass flow controller 58 as a flow rate adjusting mechanism for adjusting the flow rate of the nitrogen gas flowing through 57 and an open / close valve 59 for opening and closing the dilution gas supply line 57 are provided.

Next, the second processing unit 2 will be described.
FIG. 3 is a cross-sectional view showing a schematic configuration of the second processing unit 2. The second processing unit 2 includes a chamber 61 that can hold a wafer W and can be held in vacuum, an atmosphere forming gas supply mechanism 62 that supplies an atmosphere forming gas into the chamber 61, and an exhaust mechanism 63 that evacuates the chamber 61. It has.

  On the bottom of the chamber 61, a mounting table 64 for mounting the accommodated wafer W is provided. Inside the mounting table 64, a heater 65 for heating the wafer W is provided. Electric power is supplied to the heater 65 from a heater power supply 66. A loading / unloading port 67 for loading / unloading the wafer W is formed on the side wall of the chamber 61, and the loading / unloading port 67 is opened and closed by a gate valve G.

  A gas inlet 69 is provided in the upper portion of the side wall of the chamber 61. The atmosphere forming gas supply mechanism 62 includes an atmosphere forming gas supply source 71 for supplying an atmosphere forming gas, for example, nitrogen gas or argon gas, and an atmosphere forming. An atmosphere forming gas supply line 72 for introducing gas from the gas inlet 69 into the chamber 61; a mass flow controller 73 as a flow rate adjusting mechanism for adjusting the flow rate of the atmosphere adjusting gas flowing through the atmosphere forming gas supply line 72; An open / close valve 74 for opening and closing the supply line 72 is provided.

  An exhaust port 75 is formed in the bottom wall of the chamber 61. The exhaust mechanism 63 includes an exhaust pipe 76 connected to the exhaust port 75 and a vacuum pump 77 that exhausts the inside of the chamber 61 through the exhaust pipe 76. And a pressure adjustment valve 78 provided in the exhaust pipe 76.

  Next, an example of a procedure for applying the substrate processing method of the present invention to the formation of a dual damascene structure by the processing apparatus configured as described above will be described.

  Here, a low-k film 202, which is an upper interlayer insulating film, is formed on the low-k film 201, which is a lower interlayer insulating film, via a barrier insulating film from the cap film 206. As shown in FIG. 4A, the Cu wiring layer 203 of the Low-k film 202 is formed on the wafer W having the hard mask layer 207 formed thereon and the Cu wiring layer 203 formed on the lower Low-k film 201 as shown in FIG. When the trench 204 and the hole 205 are formed by plasma etching at a position corresponding to, etching residue 209 adhering to the side wall and the bottom wall of the trench 204 and the hole 205, or as shown in FIG. When the etching residue 209 and the resist film 208 are ashed, the side walls and bottom walls of the trench 204 and the hole 205, and the Removing ashing residue 210 adhering to the upper surface of Domasuku layer 207. Note that the hard mask layer 207 is not necessary when the resist mask 208 is sufficient as the etching mask. The etching residue 209 and the ashing residue 210 include at least one of a resist residue and a CF polymer.

Hereinafter, a description will be given with reference to the flowchart of FIG.
First, the wafer W is taken out from any one of the FOUPs F by the transfer device 16 in the loading / unloading chamber 8 and transferred to the load lock chamber 6 or 7. The wafer W is taken out and loaded into the first processing unit 1 (step 1). In the first processing unit 1, the wafer W loaded into the chamber 31 from the loading / unloading port 37 with the gate valve G opened is placed on the placing table 35, and then the gate valve G is closed to seal the inside of the chamber 31. .

  Then, the inside of the chamber 31 is adjusted to a predetermined degree of vacuum by the exhaust mechanism 34, the organic acid vapor is supplied into the chamber 31 together with the dilution gas, the vapor is condensed on the wafer W, and the Low-k film on the surface of the wafer W In this state, a liquid organic acid is present over the entire surface (step 2).

  That is, the organic acid vapor is formed by heating the liquid organic acid stored in the organic acid storage unit 51 of the organic acid supply mechanism 32 with the heater 52, but the temperature of the organic acid vapor at that time is By controlling the temperature of the temperature control medium flowing through the temperature control medium flow path 36 of the mounting table 35 so that the wafer W temperature becomes lower, the organic acid can be condensed on the surface of the wafer W.

  The heating temperature for forming the organic acid vapor varies depending on the organic acid, but when formic acid is used as the organic acid, it is preferably in the range of 25 to 100 ° C. In order to suppress liquefaction, it is preferable to heat to a temperature of 60 ° C. or higher.

  At this time, if the temperature of the wafer W (mounting table 35) is lower than the heating temperature of the organic acid, dew condensation can be performed. It is preferable that it is low. When formic acid is used as the organic acid, it is set to 8 ° C. or higher, for example, about 50 ° C., which is the freezing point of formic acid. As a result, the organic acid is condensed on the wafer W, and the surface of the low-k film 202 on the surface of the wafer W is covered with the liquid organic acid 211 as shown in the schematic diagram of FIG.

By liquefying the organic acid in this way, for example, when the organic acid is formic acid,
HCOOH → H ⁺ + HCOO ⁻
Therefore, the reactivity with the resist residue and the CF polymer constituting the etching residue or the ashing residue 209 can be increased.

  In this case, a reaction occurs between the ionized organic acid and the etching residue 209 or ashing residue 210. For example, the resist residue or CF polymer is decomposed into a low molecular weight organic compound or HF and dissolved in a liquid organic acid. And some are vaporized.

  After the processing in the first processing unit 1, the wafer W is taken out from the first processing unit 1 by the transfer device 12, and transferred to the second processing unit 2 without breaking the vacuum (step 3). In the second processing unit 2, the wafer W loaded into the chamber 61 from the loading / unloading port 67 with the gate valve G opened is placed on the placing table 64, and then the gate valve G is closed to seal the inside of the chamber 61. .

  Then, the inside of the chamber 61 is adjusted to a predetermined degree of vacuum by the exhaust mechanism 63 and, for example, nitrogen gas or argon gas is introduced into the chamber 61 as an atmosphere forming gas so that the atmosphere in the chamber 61 becomes a non-oxidizing atmosphere. At the same time, by heating and annealing the wafer W with the heater 65, the resist residue and the CF polymer existing on the wafer W are decomposed into low molecular weight organic compounds and HF as shown in the schematic diagram of FIG. Then, the solution 212 dissolved in the liquid organic acid is vaporized. That is, the organic acid present as a liquid in the solution 212 is vaporized, and at the same time, the CF polymer and the resist residue decomposition product constituting the etching residue or ashing residue 209 dissolved in the liquid organic acid are also vaporized. Is removed (step 4). When the organic acid is formic acid, a low molecular weight organic compound or HF dissolved in liquid formic acid is vaporized together with formic acid (HCOOH).

  In this case, the atmosphere in the chamber 61 may be a non-oxidizing atmosphere so that the Cu wiring is not oxidized. In addition to supplying an inert gas such as the nitrogen gas or the argon gas, a vacuum is simply applied. It may be performed only or may be an organic acid vapor atmosphere, for example, a formic acid vapor atmosphere. Alternatively, hydrogen gas may be supplied.

  The heating temperature in step 4 may be any temperature that can vaporize the organic acid and the resist residue or CF polymer decomposition product, which is an etching residue or ashing residue contained therein, but is higher than the supply temperature of the organic acid vapor. It needs to be temperature. The temperature at this time varies depending on the organic acid, but when formic acid is used as the organic acid, the temperature needs to be higher than the formic acid vapor supply temperature, and when the formic acid vapor supply temperature is about 50 ° C. It is necessary to heat to a temperature exceeding 60 ° C. More preferably, it is 150-300 degreeC.

  As described above, in the present embodiment, by causing the liquid organic acid to be present on the surface of the low-k film of the wafer W in the first processing unit 1, the ions generated by the ionization reaction and the etching residue or the ashing residue. A certain resist residue or CF polymer reacts with high reactivity, these are decomposed and dissolved in a liquid organic acid, and then heat-treated (annealed) in the second processing unit 2, thereby converting into an organic acid. Since the dissolved resist residue and the decomposition product of the CF polymer are vaporized together with the organic acid, the etching residue and the ashing residue can be surely removed without damaging the low-k film. Further, during etching or ashing, copper oxide may adhere to the Low-k film as an etching residue or ashing residue. Such copper oxide also damages the Low-k film with an organic acid such as formic acid. Can be removed without any problems.

  Moreover, in this embodiment, since the process by the liquid organic acid by the 1st process unit 1 and the annealing process by the 2nd process unit 2 are performed continuously, without being exposed to air | atmosphere, it is contained in air | atmosphere. There is no concern that Cu reacts with liquid organic acid, for example, liquid formic acid, and Cu corrosion progresses or damage to the low-k film increases.

  Further, before the processing of the wafer W, copper oxide is formed by natural oxidation of the surface of the Cu wiring layer by the atmospheric atmosphere or oxidation by an oxidizing gas used in etching or ashing, but an organic acid such as formic acid is used. As a result, the copper oxide on the surface of the Cu wiring layer can be removed simultaneously with the removal of the resist residue and the CF polymer.

  As another embodiment, a process in which the treatment with the liquid organic acid and the annealing treatment are performed in the same processing unit (the same chamber) can be exemplified. In this case, since the risk of exposure to the atmosphere can be further reduced, Cu corrosion and low-k film damage can be more effectively prevented.

  As such a processing apparatus, as shown in FIG. 8, a heater 80 is provided in addition to the temperature control medium flow path 36 inside the mounting table 35 of the apparatus of FIG. 2, and power is supplied to the heater 80 from a heater power supply 81. Can be mentioned. As a result, the process of causing the liquid organic acid to be present on the surface of the Low-k film can be performed in exactly the same manner as in the first processing unit 1, and the subsequent annealing process heats the mounting table 35 by the heater 80. Can be done. However, when the above two processes are performed in the same chamber as described above, a low temperature organic acid process and a high temperature annealing process are performed on one wafer, and then a low temperature organic acid process is performed on the next wafer. Since the cooling time becomes long, the processing apparatus as shown in FIG. 1 is preferable when the processing throughput is important. Alternatively, if the annealing treatment is performed by lamp heating, the lamp can be cooled in a relatively short time after the annealing with the lamp OFF.

  The above has described so-called single-wafer substrate processing in which the wafers W are heated one by one in a vacuum atmosphere. However, as yet another embodiment of the present invention, so-called batch-type substrate processing in which a plurality of wafers W are simultaneously heated. Can be mentioned. In the case of such a batch type substrate processing, it is not necessary to take into consideration a decrease in throughput as in the case of a single wafer type, so that the organic acid treatment and the annealing treatment can be performed in the same apparatus. Hereinafter, such a batch type substrate processing apparatus will be described. FIG. 9 is a sectional view showing such a batch type substrate processing apparatus.

  The substrate processing apparatus includes a substantially cylindrical processing container 101 for storing and processing wafers W, a wafer boat 103 for holding and storing a plurality of wafers W in the processing container 101, and the wafer boat 103. A boat elevator 104 that moves up and down between the inside and outside of the processing chamber 101, an organic acid supply mechanism 112 that supplies an organic acid into the processing vessel 101, and a dilution gas that dilutes the organic acid in the processing vessel 101, for example, nitrogen A dilution gas supply mechanism 113 that supplies gas or argon gas into the processing container 101 and an exhaust mechanism 114 that evacuates the processing container 101 are provided. The organic acid supply mechanism 112 has an organic acid supply line 121 that guides the organic acid into the processing container 101, and the dilution gas supply mechanism 113 has a dilution gas supply line 122 that guides the dilution gas into the processing container 101, and an exhaust mechanism. Reference numeral 114 denotes an exhaust pipe 123 that exhausts the processing container 101. The organic acid supply mechanism 112 is configured in the same manner as the organic acid supply mechanism 32, the dilution gas supply mechanism 113 is configured in the same manner as the dilution gas supply mechanism 33, and the exhaust mechanism 114 is configured in the same manner as the exhaust mechanism 34. Is done.

  A quartz process tube 102 is provided in the processing vessel 101, and a heater 105 for heating the inside of the process tube 102 to a predetermined temperature is provided on the outer periphery of the process tube 102 so as to surround the process tube 102. . An annular or cylindrical manifold 106 is provided at the lower end of the process tube 102. The manifold 106 includes a supply line 121 for the organic acid supply mechanism 112, a supply line 122 for the dilution gas supply mechanism 113, and an exhaust mechanism. 114 exhaust pipes 123 are connected.

  The boat elevator 104 is provided with a lid 107 that abuts the manifold 106 and holds the inside of the process tube 102 in a sealed state, and a heat retaining cylinder 108 is mounted on the lid 107.

  Each component of the substrate processing apparatus is controlled by the control unit 130. The control unit 130 is configured similarly to the control unit 20.

  In the substrate processing apparatus configured as described above, first, a plurality of wafers W are held on the wafer boat 103 in a state where the wafer boat 103 is lowered by the boat elevator 104. Next, the wafer boat 103 is raised by the boat elevator 104 and accommodated in the processing container 101. Then, the inside of the processing container 101 is adjusted to a predetermined vacuum level by the exhaust mechanism 114, and the organic acid vapor is supplied into the processing container 101 together with the dilution gas. At this time, the temperature of the wafer W is adjusted to a temperature lower than the organic acid vapor by the heater 105, and the organic acid is condensed on the surface of the low-k film of the wafer W. Thereafter, the temperature of the heater 105 is raised to vaporize the CF polymer on the wafer W together with the organic acid.

  Thus, even in such a batch type processing apparatus, the CF polymer can be removed without damaging the Low-k film.

Next, another embodiment of the present invention will be described.
As described above, the copper oxide formed on the surface of the Cu wiring layer can be removed by the organic acid, but if the copper oxide is removed and taken out to the atmosphere, it may be oxidized again. In addition, when it is taken out to the atmosphere after etching or ashing, there is a concern that the Low-k film absorbs moisture and is damaged by moisture contained in the atmosphere.

  Therefore, in the present embodiment, a multi-chamber type substrate processing apparatus capable of continuously performing etching, ashing, residue removal processing, barrier layer formation, and seed layer formation is used without breaking the vacuum. Do.

  FIG. 10 is a schematic configuration diagram showing such a substrate processing apparatus. This substrate processing apparatus includes an etching unit 151 for plasma etching a low-k film existing on the surface of a wafer as a substrate to be processed, an ashing unit 152 for ashing and removing a resist remaining after etching, and an ashing residue in a liquid state. The ashing residue is decomposed with a liquid organic acid by being treated with an organic acid, and a dissolution unit 153 for dissolving the decomposition product in the liquid organic acid, and the wafer W is annealed after the dissolution treatment in the dissolution unit 153 A vaporizing unit 154 that vaporizes and removes the organic acid and a dissolved ash residue dissolved in the organic acid from the wafer W, a barrier layer forming unit 155 that forms a barrier layer in holes reaching the Cu wiring, and the like, A seed layer forming unit 156 for forming a Cu seed layer on the layer; These units are connected to the transfer chamber 160.

  As the etching unit 151, a known plasma etching apparatus can be used. The ashing unit 152 can also use a known ashing device. The dissolution unit 153 has the same configuration as the first processing unit 1 shown in FIG. 2, and the vaporization unit 154 has the same configuration as the second processing unit 2 shown in FIG. The barrier layer forming unit 155 forms a film such as Ta, TaN, Ti, TiN, or Ru as a barrier layer by a known PVD or CVD, and the seed layer forming unit 156 is a known PVD or CVD. Thus, a Cu seed layer is formed on the barrier layer.

  Load lock chambers 166 and 167 are also connected to the transfer chamber 160. A load / unload chamber 168 is provided on the opposite side of the load lock chambers 166 and 167 from the transfer chamber 160, and a semiconductor wafer W as a substrate to be processed is provided on the opposite side of the load lock chambers 166 and 167 of the load / unload chamber 168. Are provided with ports 169, 170, and 171 for attaching three carriers C capable of accommodating the above.

  The inside of the transfer chamber 160 and the units 151 to 156 is held in a vacuum atmosphere, and the carry-in / out chamber 168 is held in an air atmosphere. The load lock chambers 166 and 167 can be switched between an air atmosphere and a vacuum atmosphere.

  As shown in the figure, the units 151 to 156 are connected to the transfer chamber 160 via a gate valve G, and these units communicate with the transfer chamber 160 by opening the corresponding gate valve G. Is closed from the transfer chamber 160. The load lock chambers 166 and 167 are connected to the transfer chamber 160 via the first gate valve G1, and are connected to the loading / unloading chamber 168 via the second gate valve G2. The load lock chambers 166 and 167 are communicated with the transfer chamber 160 by opening the first gate valve G1, and are shut off from the transfer chamber by closing the first gate valve G1. The second gate valve G2 is opened to communicate with the carry-in / out chamber 168, and the second gate valve G2 is closed to be shut off from the carry-in / out chamber 168.

  In the transfer chamber 160, a transfer device 161 that loads and unloads the semiconductor wafer W with respect to the first and second processing units 1 and 2 and the load lock chambers 166 and 167 is provided. This transfer device 161 is provided at the tip of a base 163 that travels on a rail 162 provided in the center of the transfer chamber 160, a rotation / extension / contraction part 164 that is provided to be rotatable and extendable with respect to the base 163, and the like. The two support arms 165a and 165b support the wafer W, and the two support arms 165a and 165b are attached to the rotation / extension / contraction section 164 so as to face in opposite directions.

  Three ports 169, 170, and 171 for attaching a FOUP (Front Opening Unified Pod) that is a wafer storage container of the loading / unloading chamber 168 are provided with shutters (not shown), respectively. A wafer H is accommodated or directly attached with an empty hoop F placed on the stage S, and when attached, the shutter is released to communicate with the loading / unloading chamber 168 while preventing intrusion of outside air. It has become. An alignment chamber 175 is provided on the side surface of the loading / unloading chamber 168, and the wafer W is aligned there.

  In the loading / unloading chamber 168, a transfer device 176 for loading / unloading the semiconductor wafer W into / from the FOUP F and loading / unloading the semiconductor wafer W into / from the load lock chambers 166, 167 is provided. The transfer device 176 has an articulated arm structure, and can travel on the rail 178 along the direction in which the hoops F are arranged. The semiconductor wafer W is placed on the support arm 177 at the tip thereof. Transport.

  Each component of the substrate processing apparatus is controlled by the control unit 180. The control unit 180 is configured similarly to the control unit 20.

  In the substrate processing apparatus configured as described above, the wafer W having the Low-k film as the interlayer insulating film is taken out from any one of the FOUPs F by the transfer device 176 in the loading / unloading chamber 168, and the load lock chamber 166. Alternatively, the wafer W is transported to 167 and the inside thereof is evacuated, and then the wafer W is taken out by the transport device 161 in the transport chamber 160 and transported to the etching unit 151 where Cu wiring is formed on the low-k film as an interlayer insulating film. Plasma etch to layer. Thereafter, the wafer W is taken out from the etching unit 151 by the transfer device 161 and loaded into the ashing unit 152, where the remaining resist is removed by ashing.

  Thereafter, the wafer W is taken out from the ashing unit 151 by the transfer device 161 and loaded into the melting unit 153. The dissolution unit 153 basically performs the same processing as the first processing unit 1. That is, the ashing residue is treated with a liquid organic acid, the ashing residue is decomposed with the liquid organic acid, and the decomposition product is dissolved in the liquid organic acid.

  Subsequently, the wafer W is taken out from the melting unit 153 by the transfer device 161 and loaded into the vaporization unit 154. The vaporization unit 154 basically performs the same processing as the second processing unit 2. That is, the ashing residue dissolved in the organic acid and the organic acid is vaporized and removed from the wafer W.

  The wafer W from which the ashing residue has been removed in this manner is carried into the barrier layer forming unit 155 from the vaporization unit 154 by the transfer device 161. In the barrier layer forming unit 155, for example, a film of Ta, TaN, Ti, TiN, Ru or the like is formed on the inner wall of the hole or the like from which the ashing residue has been removed to a thickness of about 2 to 50 nm by PVD or CVD. To do. Subsequently, the wafer W is taken out from the barrier layer forming unit 155 by the transfer device 161 and loaded into the seed layer forming unit 156. In the seed layer forming unit 156, a Cu seed layer is formed on the barrier layer to a thickness of about 5 to 50 nm by PVD or CVD.

  The wafer W that has been processed in the seed layer forming unit 156 is loaded into one of the load lock chambers 166 and 167 by the transfer device 161 and returned to the atmosphere there, and is transferred to any FOUP F by the transfer device 176. Returned. The wafer W subjected to these processes is transferred to a plating apparatus or the like, and a Cu buried layer is formed in a hole or the like by electrolytic plating or the like.

  As described above, in this embodiment, etching of the low-k film, ashing, residue removal processing, barrier layer formation, and seed layer formation can be performed without breaking the vacuum, so that formation of undesired copper oxide is performed. The Cu seed layer can be formed while suppressing as much as possible, and a high quality device can be obtained. Such a multi-chamber type substrate processing apparatus can be variously modified. For example, etching and ashing may be performed in the same chamber. Further, if the influence of moisture absorption by moisture in the atmosphere is small, a four-unit configuration of a dissolution unit 153, a vaporization unit 154, a barrier layer formation unit 155, and a seed layer formation unit 156 may be employed.

In addition, as a low-k film in which the processing method of the present embodiment is particularly effective, for example, HSQ (Hydrogen-silsesquioxane) containing Si, O, and H, which are siloxanes, and MSQ (SiQ, Si, O, and H) are used. Methyl-Silsesquioxane), FLAME (manufactured by Honeywell) composed of organic polyarylene ether, SILK (manufactured by Dow Chemical), polyarylene hydrocarbon, Parylene, BCB, PTFE, fluorinated polyimide, etc. What is formed as a coating film such as porous MSQ, porous SILK, and porous silica that is a porous film, and Black Diamond (Applied Materials), Coral (Novellus), Aurora (ASM) Of SiOC-based material (SiO ₂ methyl groups to the SiO bond (-CH ₃₎ to introduce those mixed with Si-CH ₃₎ and SiOF-based materials (obtained by introducing fluorine (F) to SiO ₂₎ And the like formed by CVD.

  The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the idea of the present invention. For example, in the above embodiment, the organic acid vapor is formed and condensed on the wafer in the chamber to form the liquid organic acid. However, the liquid organic acid is directly applied on the wafer by spin coating or the like. You may do it.

  In the above-described embodiment, the low-k film is used as an object to be etched. However, the present invention is not limited to this, and other interlayer insulating films or other films may be used. Moreover, although the case where the etching which reaches a Cu wiring layer was performed was shown in the said embodiment, it does not restrict to this. Although the case where a barrier insulating film is used as the cap film has been described as an example, a cap metal film or a CuSiN film selectively grown on Cu may be used.

  Furthermore, in the above embodiment, the case where the etching residue or ashing residue containing a resist residue, CF polymer, or the like is removed using an organic acid has been described, but the remaining resist itself can be removed together with the etching residue after etching, In that case, ashing is unnecessary. Furthermore, although the resist residue, CF polymer, and copper oxide were shown as an etching residue and an ashing residue in the said embodiment, not only this but another substance may be contained according to the film | membrane to etch.

  Furthermore, although the case where the Cu wiring is formed by dual damascene has been described in the above embodiment, the present invention can be applied to the case where the Cu wiring is formed by single damascene.

Furthermore, the case where a semiconductor wafer is used as the substrate has been described as an example, but other substrates such as an FPD glass substrate can also be applied.

  The present invention is suitable for removing CF polymer adhering to a predetermined film of a substrate such as a semiconductor wafer, particularly a low-k film after plasma etching.

The schematic block diagram which shows an example of the processing apparatus for enforcing the substrate processing method of this invention. Sectional drawing which shows schematic structure of the 1st processing unit 1 mounted in the processing apparatus of FIG. Sectional drawing which shows schematic structure of the 2nd processing unit 2 mounted in the processing apparatus of FIG. Sectional drawing which shows the structure of the wafer to which the substrate processing method of this invention is applied. The flowchart for demonstrating the substrate processing method which concerns on one Embodiment of this invention. The schematic diagram which shows the state at the time of forming a liquid organic acid in the Low-k film | membrane surface. The schematic diagram which shows the state at the time of annealing, after forming a liquid organic acid on the surface of a Low-k film | membrane. The schematic block diagram which shows the substrate processing apparatus for enforcing other embodiment of the substrate processing method of this invention. The schematic block diagram which shows the substrate processing apparatus for enforcing further another embodiment of the substrate processing method of this invention. The schematic block diagram which shows the substrate processing apparatus for enforcing another embodiment of the substrate processing method of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1; 1st processing unit 2; 2nd processing unit 5,160; Transfer chamber 6,7,166,167; Load lock chamber 8,168; Loading / unloading chamber 12,16,161,176; 180; control unit 31, 61; chamber 32, 112; organic acid supply mechanism 34, 114; exhaust mechanism 35, 64; mounting table 36; temperature control medium flow path 37, 67; loading / unloading port 40; shower head 101; 102; Process tube 103; Wafer boat 151; Etching unit 152; Ashing unit 153; Dissolution unit 154; Vaporization unit 155; Barrier layer formation unit 156; Seed layer formation unit 201, 202; Low-k film 203; Cu wiring layer 204 ; Trench 205; hole 209; etching residue 210; Residue 211; liquid organic acid 212; solution G; gate valve W; semiconductor wafer

Claims (23)

An etching residue remaining on the surface of a predetermined film after dry etching the substrate, or a substrate processing method for removing an ashing residue remaining on the surface of the film after ashing the etching residue and resist,
Forming a liquid organic acid on the substrate surface, decomposing the etching residue or ashing residue with the liquid organic acid, and dissolving the decomposition product in the liquid organic acid;
And a second step of annealing the substrate to vaporize and remove the organic acid and the dissolved ashing residue dissolved in the organic acid from the substrate.   The substrate processing method according to claim 1, wherein the etching residue or the ashing residue includes at least one of a resist residue and a CF polymer.   The substrate has a Cu wiring layer, and a cap film and a Low-k film formed thereon, and the cap film and the Low-k film are plasma-etched up to the Cu wiring layer, or further 2. The substrate processing method according to claim 1, wherein the substrate is processed by ashing, and the etching residue or the ashing residue is attached to at least the Low-k film.   The substrate processing method according to claim 3, wherein the etching residue or the ashing residue is at least one of a resist residue, a CF polymer, and copper oxide.   In the first step, the substrate is placed on a mounting table provided in the processing chamber, and the organic acid vapor is introduced into the processing chamber in a state where the processing chamber is evacuated, and the organic acid vapor is condensed on the substrate surface. 5. The substrate processing method according to claim 1, wherein a liquid organic acid is formed on the surface of the substrate.   In the second step, the substrate subjected to the first step is placed on a mounting table provided in the processing chamber, the substrate is evacuated, and the substrate is heated in a non-oxidizing atmosphere. The substrate processing method according to claim 5, wherein the substrate processing method is performed.   The substrate processing method according to claim 6, wherein the first step and the second step are performed without breaking a vacuum. A first processing unit that performs the first step; a second processing unit that performs the second step; and a transport device that transports the substrate by connecting the first processing unit and the second processing unit. Equipped with a processing apparatus having a transfer chamber held in a vacuum,
After the first process is performed on the substrate by the first processing unit, the substrate is transported to the second processing unit by the transport device, and the second process is performed on the substrate by the second processing unit. The substrate processing method according to claim 7.   The substrate processing method according to claim 1, wherein the first process and the second process are performed in the same processing unit.   The substrate processing method according to claim 1, wherein the organic acid is a carboxylic acid.   The substrate processing method according to claim 10, wherein the organic acid is formic acid.   In the first step, a substrate is placed on a mounting table provided in a processing chamber, and formic acid vapor is formed by heating liquid formic acid to 25 to 100 ° C. in a state where the processing chamber is evacuated. The formic acid vapor is introduced into the processing chamber, and the formic acid vapor is condensed on the substrate surface by maintaining the substrate at a temperature of 8 ° C. or more and 5 ° C. or more lower than the heating temperature, thereby forming liquid formic acid on the substrate surface. The substrate processing method according to claim 11.   The said 2nd process heats the board | substrate with which the said 1st process was performed at 150-300 degreeC, and vaporizes the dissolved substance of the etching residue or the ashing residue which melt | dissolved in formic acid and formic acid, The substrate processing method according to claim 12. Plasma etching a portion corresponding to the Cu wiring layer of the cap film and the Low-k film on a substrate having a Cu wiring layer and a cap film and a Low-k film formed thereon;
Removing the etching residue and resist of the etching by ashing;
After ashing, forming a liquid organic acid on the surface of the low-k film to which the ashing residue adheres, decomposing the ashing residue with the liquid organic acid, and dissolving the decomposition product in the liquid organic acid; ,
Thereafter, annealing the substrate, evaporating the ashing residue dissolved in the organic acid and the organic acid, and removing from the substrate,
Forming a barrier layer in a hole or trench reaching the exposed Cu wiring formed by the dry etching;
Forming a Cu seed layer on the barrier layer, and performing all the steps without breaking the vacuum. A processing chamber in which a substrate having an etching residue remaining on the surface of a predetermined film after dry etching, or a substrate having an ashing residue remaining on the surface of the film after ashing the etching residue and the resist is carried in, and can be maintained in a vacuum. A mounting table on which the substrate is placed, an organic acid vapor supply mechanism that supplies organic acid vapor into the processing chamber, and a temperature of the substrate on the mounting table, the temperature of the organic acid vapor. A first processing unit having a temperature adjustment mechanism for adjusting the temperature to a lower temperature,
A processing chamber in which a substrate after processing in the first processing unit is carried in and can be maintained in vacuum, a mounting table on which the substrate is mounted, and a substrate on the mounting table are heated. A second processing unit having a heating mechanism,
The substrate having the etching residue or the ashing residue is carried into the processing chamber of the first processing unit, the organic acid vapor is supplied from the organic acid supply mechanism to the processing chamber, and the substrate is The organic acid is condensed on the surface of the substrate by adjusting the temperature to a temperature lower than the temperature of the substrate, thereby forming a liquid organic acid on the substrate surface, and the etching residue or ashing residue is decomposed by the liquid organic acid. And the decomposition product is dissolved in the liquid organic acid.
The substrate on which the liquid organic acid is formed is carried into the processing chamber of the second processing unit, heated by the heating mechanism, and the etching residue or the ashing residue dissolved in the organic acid is vaporized. And removing the substrate from the substrate.   The first processing unit and the second processing unit are connected to each other, and includes a transport device that transports the substrate, and further includes a transport chamber held in a vacuum, and the processing by the first processing unit and the second The substrate processing apparatus according to claim 15, wherein the processing by the processing unit is performed without breaking a vacuum. A processing chamber in which a substrate having an etching residue remaining on the surface of a predetermined film after dry etching, or a substrate having an ashing residue remaining on the surface of the film after ashing the etching residue and the resist is carried in, and can be maintained in a vacuum. ,
A mounting table for mounting a substrate provided in the processing chamber;
An organic acid vapor supply mechanism for supplying organic acid vapor into the processing chamber;
A temperature adjustment mechanism for adjusting the temperature of the substrate on the mounting table to a temperature lower than the temperature of the organic acid vapor;
A heating mechanism for heating the substrate on the mounting table,
The substrate having the etching residue or the ashing residue is carried into the processing chamber, the organic acid vapor is supplied from the organic acid supply mechanism to the processing chamber, and the substrate is lower than the temperature of the organic acid vapor by the temperature control mechanism. The temperature is adjusted to a temperature and the organic acid is condensed on the substrate surface, whereby a liquid organic acid is formed on the substrate surface, and the etching residue or ashing residue is decomposed by the liquid organic acid and the liquid state. The decomposition product is dissolved in the organic acid of
The substrate processing apparatus, wherein the substrate is heated by the heating mechanism, and the etching residue or the dissolved ashing residue dissolved in the organic acid is vaporized and removed from the substrate. A process in which a plurality of substrates having an etching residue remaining on the surface of a predetermined film after dry etching, or an ashing residue remaining on the surface of the film after ashing the etching residue and resist are carried in, and can be maintained in a vacuum. A container,
A substrate holding member for holding a plurality of substrates in the processing container;
An organic acid vapor supply mechanism for supplying organic acid vapor into the processing vessel;
A temperature adjustment mechanism for adjusting the temperature of the plurality of substrates held by the holding member to a temperature lower than the temperature of the organic acid vapor;
A heating mechanism for heating the plurality of substrates held by the holding member,
The substrate having the etching residue or the ashing residue is carried into the processing container, the organic acid vapor is supplied from the organic acid supply mechanism to the processing container, and the substrate is lower than the temperature of the organic acid vapor by the temperature control mechanism. Liquid organic acid is formed on the substrate surface by dew condensation on the substrate surface by adjusting the temperature to the temperature, and the etching residue or ashing residue is decomposed by the liquid organic acid and the liquid state The decomposition product is dissolved in the organic acid,
The substrate processing apparatus, wherein the substrate is heated by the heating mechanism, and the etching residue or dissolved ashing residue dissolved in the organic acid is vaporized and removed from the substrate.   19. The substrate processing apparatus according to claim 15, wherein the etching residue or the ashing residue includes at least one of a resist residue and a CF polymer.   The substrate has a Cu wiring layer and a Low-k film formed thereon, and the Low-k film is plasma-etched up to the Cu wiring layer or is further ashed. 19. The substrate processing apparatus according to claim 15, wherein the etching residue or the ashing residue is attached to the Low-k film.   21. The substrate processing apparatus according to claim 20, wherein the etching residue or the ashing residue includes at least one of a resist residue, a CF polymer, and copper oxide. An etching unit for plasma etching a portion of the Low-k film corresponding to the Cu wiring layer with respect to a substrate having a Cu wiring layer and a Low-k film formed thereon;
An ashing unit for removing the etching residue and resist of the etching by ashing;
After ashing, a dissolution unit that forms a liquid organic acid on the surface of the low-k film to which the ashing residue adheres, decomposes the ashing residue with the liquid organic acid, and dissolves the decomposition product in the liquid organic acid When,
After the dissolution treatment in the dissolution unit, the substrate is annealed to vaporize and remove the ashing residue dissolved in the organic acid and the organic acid from the substrate,
A barrier layer forming unit for forming a barrier layer in a hole reaching the exposed Cu wiring formed by the dry etching;
A seed layer forming unit for forming a Cu seed layer on the barrier layer;
The etching unit, the ashing unit, the melting unit, the vaporization unit, the barrier layer forming unit, and the seed layer forming unit are connected to each other, and includes a transfer device that transfers a substrate, and a transfer chamber that is held in a vacuum. Equipped,
Processing by the etching unit, the ashing unit, the dissolution unit, the vaporization unit, the barrier layer forming unit, and the seed layer forming unit is performed in a vacuum, and transfer between each unit is performed through the transfer chamber. Accordingly, the substrate processing apparatus can perform processing of all the units without breaking the vacuum.   15. A storage medium that operates on a computer and stores a program for controlling a processing apparatus. The program is stored in a computer so that the substrate processing method according to claim 1 is performed at the time of execution. A storage medium for controlling a processing device.

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