KR20180099504A - Semiconductor manufacturing method and plasma processing apparatus - Google Patents

Abstract

An object of the present invention is to prevent corrosion of a conductive layer on an object to be processed during manufacturing of a semiconductor. The method for manufacturing a semiconductor includes a first step of etching an insulating film on the conductive layer of the object using a pattern of a mask, and exposing the conductive layer to a concave portion formed on the insulating film; and a second step of forming an organic film on the concave portion of the insulating film from which the conductive layer is expose. The second step includes a step of maintaining the inside of a chamber at a predetermined pressure, cooling a stage at a cryogenic temperature of -20°C or lower, and providing the object on the stage, a step of supplying gas containing gas of a low vapor pressure material into the chamber, and a step of forming the organic film by generating plasma from the supplied gas containing the gas of the low vapor pressure material, and depositing a precursor generated from the low vapor pressure material on the concave portion of the insulating film by using the plasma.

Description

Technical Field [0001] The present invention relates to a semiconductor manufacturing method and a plasma processing apparatus,

The present invention relates to a semiconductor manufacturing method and a plasma processing apparatus.

It is known to expose a part of a conductive layer including a metal such as a Cu wiring formed on a semiconductor wafer by performing dry etching on the semiconductor wafer (see, for example, Patent Documents 1 to 4). When the semiconductor wafer is exposed to the atmosphere in this state, the exposed conductive layer reacts with moisture in the atmosphere and changes with time and corrodes. Therefore, in order to minimize the corrosion of the conductive layer, the time from the end of the dry etching process to the start of the next process (so-called "Q-time") is managed.

In contrast, it has been proposed to coat the conductive layer with a protective film to suppress corrosion of the conductive layer. For example, Patent Document 1 proposes that a metal film such as Cu wiring is covered with a protective film by applying a liquid used for immersion exposure in a lithography process to the surface of the metal.

Patent Document 1: JP-A-2015-046449 Patent Document 2: Japanese Patent Application Laid-Open No. 2015-065396 Patent Document 3: Japanese Patent Application Laid-Open No. 2015-149410 Patent Document 4: JP-A-2016-103595

However, in the above technique, when the semiconductor wafer after etching is transferred to the exposure apparatus, the semiconductor wafer before being coated with the protective film is exposed to the atmosphere, so that it is not sufficient to prevent corrosion of the exposed metal film. Further, in the above technique, an exposure apparatus different from the etching apparatus is required, which is costly.

In view of the above problems, in one aspect, the present invention aims to prevent corrosion of a conductive layer on an object to be processed in semiconductor manufacturing.

According to an aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: a first step of etching an insulating film on a conductive layer of an object to be processed in a mask pattern and exposing the conductive layer to a concave portion of the insulating film; And a second step of forming an organic film in the concave portion of the exposed insulating film, wherein the second step is a step of holding the inside of the chamber at a predetermined pressure, cooling the stage to a cryogenic temperature of -20 占 폚 or less, A step of supplying a gas containing a gas of a low vapor pressure material to the inside of the chamber, a step of generating plasma from a gas containing the supplied gas of the low vapor pressure material, Depositing a precursor generated from the low vapor-pressure material on the concave portion of the insulating film by a chemical vapor deposition This crude method is provided.

According to one aspect, it is possible to prevent corrosion of the conductive layer on the object to be processed in semiconductor manufacturing.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a view showing an example of a process according to an embodiment and a process according to a comparative example;
2 is a flowchart showing an example of a semiconductor manufacturing method according to an embodiment;
3 is a view showing an example of experimental results of a film forming method in semiconductor manufacturing according to one embodiment;
4 is a diagram showing an example of experimental results of a film forming method in semiconductor manufacturing according to one embodiment;
5 is a graph showing an example of an experimental result of time variation of a film by a film forming method according to an embodiment.
6 is a view showing an example of experimental results of a film forming method in semiconductor manufacturing according to an embodiment;
7 is a view showing an example of experimental results of a film forming method in semiconductor manufacturing according to one embodiment;
8 is a view showing a vapor pressure curve.
9 is a view showing an example of a result of film thickness and metal corrosion by the film forming method according to one embodiment;
10 is a view showing an example of a result of film thickness and corrosion of a metal by a film forming method according to an embodiment;
11 is a diagram showing an example of the result of ashing by the ashing method according to the embodiment;
12 is a view showing an example of a processing system according to an embodiment;
13 is a view showing an example of a plasma processing apparatus according to an embodiment;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, modes for carrying out the present invention will be described with reference to the drawings. In the present specification and drawings, substantially the same constituent elements are denoted by the same reference numerals, and redundant description is omitted.

[Semiconductor manufacturing method]

First, an example of a semiconductor manufacturing method according to one embodiment of the present invention will be described in comparison with a semiconductor manufacturing method according to a comparative example. 1 (a-1) and 1 (a-2) show one example of a semiconductor manufacturing method according to a comparative example, An example of a manufacturing method is shown.

The semiconductor manufacturing method according to the present embodiment is a method for manufacturing a semiconductor device in which a semiconductor wafer (hereinafter referred to as " wafer W ") is etched to expose at least a part of a conductive layer, It is possible to carry out the processing of the next step. Here, the Q-time is a time limit from the end of a previous step such as a dry etching process to the start of the next process, and indicates that a conductive layer such as a metal wiring exposed by dry etching is oxidized (corroded) . When Q-time is set, time management is required to comply with Q-time. The wafer W is an example of an object to be processed.

The wafer W has, for example, a wiring layer 101, a liner film 103, and an interlayer insulating film 104 as shown in Figs. 1 (a-1) and 1 (b- These are stacked in this order of the wiring layer 101, the liner film 103 and the interlayer insulating film 104. A Cu wiring 102 is formed in the wiring layer 101. The Cu wiring 102 is an example of a conductive layer such as a metal wiring.

A via hole H is formed in the wafer W by dry etching. The via hole H is a concave portion formed in the interlayer insulating film 104. The concave portion is formed by etching the interlayer insulating film 104 in the pattern of the TiN film 105. [ The concave portion reaches the wiring layer 101 by etching the liner film 103 and the surface of the Cu wiring 102 is exposed from the bottom of the concave portion of the via hole H. [ The interlayer insulating film 104 is an example of an insulating film, and may be a SiO ₂ film or an SiN film, for example. An insulating film is used for the liner film 103, and may be an SiN film, a SiC film, or an SiCN film, for example. The TiN film 105 is an example of a mask on an insulating film. The Cu wiring 102 is an example of a metal film.

In the comparative example, the wafer W after the dry etching is taken out of the etching apparatus in a state in which the Cu wiring 102 is exposed, and is transported to the cleaning apparatus in the next step. During the transportation, the Cu wiring 102 and the TiN film 105, which are the metal parts in the laminated film on the wafer W, are exposed to the atmospheric space and react with moisture in the air. Therefore, as shown in (a-2) of FIG. 1, when the wafer W is carried into the cleaning apparatus, the surfaces of the Cu wiring 102 and the TiN film 105 are corroded.

On the other hand, in the semiconductor manufacturing method according to the present embodiment, after the dry etching shown in FIG. 1 (b-1), a predetermined aspect ratio (A / R) The inside of the concave portion of the via hole H is filled with the fluid organic film 106 without blocking the top opening of the concave portion. Thus, during the transportation in the cleaning apparatus of the next step, the Cu wiring 102 and the TiN film 105 are not exposed to the atmospheric space. Therefore, as shown in FIG. 1 (b-3), when the wafer W is carried into the cleaning apparatus, the Cu wiring 102 and the TiN film 105 are not corroded. 1 (b-3), the flowable organic film 106 filled in the concave portion of the via hole H by the cleaning device while preventing the Cu wiring 102 and the TiN film 105 from being corroded, Can be removed.

[Etching process / film forming process / cleaning process]

The etching step, the film forming step and the cleaning step in the semiconductor manufacturing according to the embodiment described above will be described with reference to a flowchart showing an example of the semiconductor manufacturing method according to the embodiment of FIG. First, the etching apparatus carries the wafer W, and etches the interlayer insulating film 104 until the liner film 103 is exposed (step ST1). Next, the etching apparatus etches the liner film 103 until the Cu wiring 102 is exposed (step ST2). Thus, a via hole H is formed. Further, in the etching of step ST1 and step ST2, it may be used as the gas containing the halogen such as CF ₄ gas and NF ₃ gas. In order to treat the surface of the exposed Cu wiring 102 after the etching in the step ST2, even if a treatment with a plasma generated from a gas containing H ₂ and N ₂ or a gas containing NH ₃ gas is performed good.

Next, in the in-system, the wafer W is vacuum-transferred from the etching apparatus to the deposition apparatus, or in-situ is performed in the same chamber as the chamber in which the etching process of steps ST1 and ST2 has been performed The fluid organic film 106 is formed (step ST3).

Refers to a processing system capable of vacuum transferring from one plasma processing apparatus to another plasma processing apparatus. An example of the configuration of the processing system (Fig. 12) will be described later. In situ refers to a plasma processing apparatus capable of performing one substrate processing and another substrate processing in the same chamber. An example of the configuration of the plasma processing apparatus (Fig. 13) will be described later. After the film formation, the wafer W is transported to the cleaning apparatus under an atmospheric environment (step ST4). The cleaning apparatus cleans the wafer W (step ST5).

[Flowable organic film / film forming condition 1]

Next, the flowable organic film to be formed in step ST3 will be described with reference to Figs. 3 to 8. Fig. Figs. 3 to 7 show an example of experimental results of the film forming method of the fluid organic film in the semiconductor manufacturing according to the present embodiment. 8 shows a vapor pressure curve of a predetermined material. The film forming condition 1 of the fluid organic film in Experiment 1 shown in Fig. 3 is as follows.

<Film forming condition 1>

Pressure in the chamber: 100 mT (13.3 Pa)

Gas species / flow rate: C ₄ F ₆ 300 sccm

Stage temperature: -50 ° C

Duration: 5 sec

Power of high-frequency HF: 300 W

High frequency LF power: 0 W

Among the results of Experiment 1, "SiN L & S", "High A / R", and "(c)" Organic L & S "in FIG. 3A are examples of the object to be processed The state of the organic film deposited on each sample is shown. (a) In the &quot; SiN L &amp; S &quot;, a patterned SiN film 1 having a low density is formed on the wafer W. The aspect ratio of the concave portion patterned in the SiN film 1 is not uniform but has a concave portion with an aspect ratio of 3 to 5 and a flat portion shown at the lower end of Fig.

(b) In the sample of &quot; High A / R &quot;, the SiN film 1 on which the concave portion with the aspect ratio of 18 is formed is formed on the wafer W. (c) In the sample of &quot; Organic L &amp; S &quot;, a line and space having an aspect ratio of 2 is formed on the wafer W. In the sample of "Organic L &S", the base film is the SiO ₂ film 2, and the organic film 3 and the Si-ARC (Anti Reflective Coating) film 4 are stacked thereon. The aspect ratio of the concave portion formed in the sample of &quot; Organic L & S &quot; is 2, and in the semiconductor manufacturing method according to the present embodiment, the film is formed on the concave portion of each sample having the aspect ratio of 2 or more.

3 to 7, the SiN film 1 or the organic film 3 is described as an example of the interlayer insulating film 104 shown in FIG. According to the results of Figure 3, (a), "SiN L &S", (b) the in all samples of "High A / R", (c) "Organic L &S", produced from the C ₄ F ₆ gas in the recess on the sample A precursor in the plasma is deposited to form a fluid organic film (R). Voids do not occur because the fluid organic film R is deposited by being piled up from the bottom of the concave portion. The void is a cavity formed in the inside of the concave portion by closing the opening of the concave portion of the via hole (H). Experimental results shown in Figs. 3 to 7 show the state of the fluid organic film R deposited in this embodiment as an example of the fluid organic film 106 shown in Fig.

[Fluid organic film / film forming condition 2]

Next, an example of the change of the film with the film formation time of the fluid organic film (R) using the sample of "SiN L & S" will be described with reference to FIG. The film forming condition 2 of the fluid organic film in Experiment 2 shown in Fig. 4 is as follows.

<Film forming condition 2>

Pressure in the chamber: 50 mT (6.65 Pa)

Gas species / flow rate: C ₄ F ₆ 300 sccm

Stage temperature: -50 ° C

Power of high-frequency HF: 300 W

High frequency LF power: 0 W

Among the results of Experiment 2, FIG. 4 (a) shows the fluid organic film R when the film forming time is 2 seconds. 4A, it can be seen that the concave portion F having a higher aspect ratio than the concave portions A, C, and E is filled with the fluid organic film R faster than the concave portions A, C, and E .

4 (b) shows the fluid organic film R when the film formation time is 4 seconds. 4B, the fluid organic film R is not deposited in the concave portions B and D and the fluid organic film R is formed in the holes of the concave portions A, C and E more than the concave portions B and D. It can be seen that the fluidized organic film R is deposited in the concave portion G as well. At this point in time, the fluid organic film R was hardly deposited on the plane portion H.

4 (c) shows the flowable organic film R when the film formation time is 7 seconds. In Fig. 4C, the deposition of the fluid organic film R is also seen in the plane portion H. Fig. 4 (d) shows the fluid organic film R when the film formation time is 10 seconds. 4 (d), the concave portions A to G are substantially filled with the fluid organic film R, and more fluid organic film R is deposited even in the flat portion H. 4 (e) shows the state of the fluid organic film R when the film formation time is 30 seconds. 4 (e), all of the concave portions and the flat portion H are filled with the fluid organic film R.

As described above, according to the semiconductor manufacturing method of the present embodiment, the flowable organic film R is formed by the precursor in the plasma generated from the C ₄ F ₆ gas. At this time, it can be seen that the fluid organic film R is formed by growing backwards from the bottom of the concave portion.

It is also understood that the higher the aspect ratio of the concave portion, the faster the film forming speed is. It can also be seen that the film forming speed at the concave portions A to G of the wafer W is faster than the film forming speed at the flat portion H of the wafer W. [

Fig. 5 is a graph showing the experimental results of Fig. The abscissa of the graph is the deposition time (sec), and the ordinate is the thickness of the deposit (nm). Curve J shows the temporal change of the film thickness of the small hole with the aspect ratio of 12 shown on the left side of Fig. And the curve K represents the time variation of the film thickness of the intermediate hole having an aspect ratio of 4.3. The curve L shows the time variation of the film thickness of a large hole having an aspect ratio of 3.6. The curve M shows the change with time of the film thickness of the deposit deposited on the top (top) of the SiN film 1 serving as the mask. Curve N shows the change with time of the film thickness of the deposit deposited in the open area.

5, when the height of the bottom of the SiN film 1 is 0 nm, the height of the top of the SiN film 1 is 110 nm. Therefore, no sediment is deposited on the top of the SiN film 1 in a time zone in which the curve M shows a thickness of 110 nm. In the graph, the curve begins to rise in the order of curve J → curve K → curve L. That is, it can be seen that the fluid organic film R is filled in the order of the small hole indicated by the curve J → the intermediate hole indicated by the curve K → the large hole indicated by the curve L in this order.

Further, the thickness of the sediment on the top (mask) of the SiN film 1 indicated by the curve M shows that the fluidized organic film R is in contact with the top of the SiN film 1 after the small holes, As shown in FIG. Further, in the plane portion indicated by the curve N, the fluidized organic film R begins to be deposited before the film formation time in which all of the small holes, the middle holes and the large holes are filled with the fluid organic film R, The deposition rate is approximately equal to the normal deposition rate of the SiN film 1.

[Fluid organic film / deposition condition 3]

Next, temperature dependence and pressure dependence of the fluid organic film R will be described with reference to FIG. 6, the temperature of the stage on which the wafers W are placed is set to a temperature of -20 DEG C or more at a cryogenic temperature and the pressure in the chamber is set to 50 mT or more. For example, FIG. 6A shows the state of the film at each temperature when the chamber is maintained at a pressure of 100 mT and C ₄ F ₆ gas is supplied at 300 sccm. According to this, in the case of -10 占 폚 and -20 占 폚, the film formation in the backward direction is performed, the opening of the SiN film 1 becomes narrow, and voids V are generated. That is, by the semiconductor manufacturing method according to the present embodiment, the film formation in which the fluid organic film R is stacked upside down is not performed. On the other hand, in the case of -30 占 폚 and -50 占 폚, the film formation in which the fluid organic film R was stacked upside down was performed, and the void V did not occur. In addition, the results in the case of -40 占 폚 were not obtained.

6 (b) shows the state of the film at each temperature when the chamber is maintained at a pressure of 50 mT and IPA (isopropyl alcohol: C ₃ H ₈ O) gas is supplied at 75 sccm. IPA is one kind of secondary alcohol. According to this, voids (V) are generated in the case of -10 DEG C and -30 DEG C and film formation in the backward direction is performed, and in the case of -40 DEG C and -50 DEG C, The flowable organic film R is formed upside down. In addition, the results in the case of -20 占 폚 were not obtained.

6 (c) shows the state of the film at each temperature when the inside of the chamber is maintained at a pressure of 50 mT and C ₄ F ₆ gas is supplied at 300 sccm. According to this, the voids (V) are generated in the case of -10 캜, and the film formation in the backward direction is performed. In the case of -20 캜, -30 캜 and -50 캜, the fluid organic film R is formed upside down . In addition, the results in the case of -40 占 폚 were not obtained.

6 (d) shows the state of the film at each temperature when the inside of the chamber is maintained at a pressure of 50 mT and C ₄ F ₆ gas is supplied at 125 sccm. According to this, voids (V) are generated in the case of -10 占 폚 and -20 占 폚 and film formation in the backward direction is carried out. In the case of -30 占 폚, the fluid organic film R is formed upside down. Also, the results in the case of -40 ° C and -50 ° C were not obtained.

From the above, it can be seen that the temperature at which the concave portion can be filled by the fluid organic film R differs depending on the gas species, the pressure and the gas flow rate. When the inside of the chamber is maintained at a pressure of 50 m and the C ₄ F ₆ gas is supplied at 300 sccm, the stage is kept at an extremely low temperature of -20 캜 or lower, and the pressure in the chamber is set to 50 mT or higher, And can be filled with the organic film R. [

[Fluid organic film / deposition condition 4]

Next, the dependence of the flowable organic film R on the gas species will be described with reference to FIGS. 7 and 8. FIG. Fig. 7 shows an example of the result of the film forming process according to the present embodiment by changing the gas species. According to the results of this experiment, in the C ₄ F ₆ gas, the IPA (C ₃ H ₈ O) gas, and the C ₄ F ₈ gas, the recess is filled with the fluid organic film (R) I did. On the other hand, CH ₄ gas, CH ₃ F gas, the CF ₄ gas, and a void (V) occurs, it could not be filled by a liquid organic film recess (R).

8 shows vapor pressure curves of C ₄ F ₆ gas, IPA (C ₃ H ₈ O) gas, C ₄ F ₈ gas, CH ₄ gas, CH ₃ F gas and CF ₄ gas. The CH ₄ gas, the CH ₃ F gas and the CF ₄ gas in which voids are formed in the film become vapor pressure at a lower temperature than the vapor pressure curve of the C ₄ F ₈ gas. On the other hand, C ₄ F ₈ , C ₄ F ₆ , and isopropyl alcohol (IPA) in which voids are not generated in the film and the fluid organic film (R) is formed in an inverted manner is the vapor pressure curve of the C ₄ F ₈ gas The vapor pressure becomes equal to or higher than the temperature. A gas that becomes a vapor pressure at a temperature higher than the temperature indicated by the vapor pressure curve of the C ₄ F ₈ gas is called a &quot; gas of a low vapor pressure material &quot;.

From the above results, it can be seen that the semiconductor manufacturing method according to the present embodiment includes the steps of: placing the wafer W on a stage cooled at a cryogenic temperature of -20 DEG C or lower while maintaining the inside of the chamber 10 at a predetermined pressure; , And supplying a gas containing a gas of a low vapor pressure material to the inside of the chamber (10). Further, in the semiconductor manufacturing method according to the present embodiment, a plasma is generated from a supplied gas containing a gas of the low vapor-pressure material, and a plasma is generated on the wafer W by a precursor generated from the low- As shown in FIG. According to this, it becomes possible to form the fluid organic film R, which is deposited from the bottom of the concave portion, upside down. At this time, it is preferable that the pressure inside the chamber 10 is not less than 50 mT (6.67 Pa), and is not more than the vapor pressure indicated by the vapor pressure curve of the gas of the low vapor-pressure material.

The "gas of low vapor pressure material" may be a carbon-containing gas. Specific examples of the carbon-containing gas include C ₄ F ₈ , C ₄ F ₆ and isopropyl alcohol (IPA). Thus, according to the semiconductor manufacturing method of the present embodiment, the precursor generated from the low vapor-pressure material can be deposited from the bottom of the concave portion formed in the wafer W to form the fluid organic film on the wafer W .

[Thickness and Corrosion of Metal]

Figs. 9 and 10 show an example of the effect of preventing corrosion of the metal film by the fluid organic film R formed in the step ST3 of Fig. In the present embodiment (b) of Fig. 9, a flowable organic film (R) having a thickness of 4 nm is formed on the bracket of a TiN film under the following film forming conditions, and the TiN film is coated. The comparative example (a) in Fig. 9 is a case in which the fluid organic film (R) is not coated on the bracket of the TiN film (no cap). With respect to these two kinds, there is shown an example of a change with time in the surface of the TiN film after being left in an atmospheric environment for 24 hours.

&Lt; Conditions for forming a fluid organic film &

Pressure in the chamber: 100 mT

Gas species / flow rate: C ₄ F ₆ 300 sccm

Stage temperature: -50 ° C

Power of high-frequency HF: 300 W

High frequency LF power: 0 W

According to the results shown in Fig. 9, in the case of the comparative example (a), the surface of the TiN film was altered as a result of the reaction of fluorine with moisture in the atmosphere, and it was found that the irregularities were formed and corroded. On the other hand, in the case of the present embodiment (b), it can be seen that the surface of the TiN film is not deteriorated by the fluidized organic film R, and is not corroded, and is not corroded.

Fig. 10 is a graph showing the relationship between the film forming conditions of the TiN film coated with the 40 nm thick fluidized organic film (R) (the present embodiment (b)) and the TiN film not coated (Comparative Example (a) , And an example of a change with time in the surface of the TiN film after being left in an atmospheric environment for 24 hours.

According to the results shown in Fig. 10, in the case of Comparative Example (a), as a result of the reaction of fluorine and moisture in the atmosphere, the surface of the TiN film was altered to form irregularities and corrosion . On the other hand, in the case of the present embodiment (b), it can be seen that the surface of the TiN film is not deteriorated by the fluidized organic film R, and is not corroded, and is not corroded. From the above experimental results, it can be seen that the thickness of the fluid organic film R is at least 4 nm.

[Ashing]

Next, an example of a cleaning process of the wafer W to be executed in step ST5 in Fig. 2 will be described with reference to Fig. The present embodiment shows an example of the result of ashing by oxygen plasma as an example of cleaning. The ashing conditions are shown below.

<Ashing condition>

Pressure in the chamber: 100 mT

Gas type / flow rate: O ₂ 900 sccm

Stage temperature: 80 캜

Power of high-frequency HF (60 MHz): 500 W

Power of high-frequency LF (400 kHz): 100 W

11A is a graph showing the relationship between the ashing time and the ashing time of the SiN film 1 when the ashing time is 0 second, the ashing time is 10 seconds, the ashing time is 15 seconds, and the ashing time is 20 seconds. Represents the state of the fluid organic film (R). According to this, it can be seen that the flowable organic film R is completely removed by the O ₂ plasma when the ashing time has passed 20 seconds.

From the above, it can be seen that the fluid organic film R can be removed by the O ₂ plasma. However, the fluid organic film R is not limited to the plasma cleaning by the O ₂ plasma, and may be removed by wet cleaning.

[Processing system]

Next, an example of a processing system in which the etching process in steps ST1 and ST2 in FIG. 2 and the film forming process in step ST3 are performed will be described with reference to FIG. 12 shows an example of the processing system 100 in which the etching process by the etching apparatus according to the present embodiment and the film forming process by the film forming apparatus can be executed in the In-system.

The processing system 100 has an etching apparatus PM1 for performing the etching process in steps ST1 and ST2 and a film forming apparatus PM2 for performing the film forming process in step ST3. In the processing apparatus PM3 and the processing apparatus PM4, an etching step or a film forming step may be performed.

The etching apparatus PM1, the film forming apparatus PM2, the processing apparatus PM3 and the processing apparatus PM4 are provided corresponding to the four sides of the hexagonal transport chamber 5, respectively. Further, load lock chambers 6 and 7 are provided on the other two sides of the transport chamber 5, respectively. A loading / unloading chamber (8) is provided on the side of these load lock chambers (6, 7) opposite to the carrying chamber (5). Ports 9, 10, and 11 for attaching three Foups F capable of accommodating the wafers W are provided on the opposite side of the load lock chambers 6 and 7 of the loading / unloading chamber 8.

The etching apparatus PM1, the film forming apparatus PM2, the processing apparatuses PM3 and PM4 and the load lock chambers 6 and 7 are connected to the respective sides of the hexagonal shape of the transfer chamber 5 via gate valves G . Each chamber communicates with the transfer chamber 5 by opening each gate valve G and is shut off from the transfer chamber 5 by closing each gate valve G. [ A gate valve G is also provided at a portion connected to the loading / unloading chamber 8 of the load lock chambers 6, 7. The load lock chambers 6 and 7 communicate with the loading and unloading chamber 8 by opening the gate valve G and are shut off from the loading and unloading chamber 8 by closing.

The transfer chamber 5 is provided with a transfer device for transferring and unloading the wafers W to the etching apparatus PM1, the film forming apparatus PM2, the processing apparatuses PM3 and PM4 and the load lock chambers 6 and 7 112 are installed. The transfer device 112 includes two blades 114a and 114b which are disposed substantially at the center of the transfer chamber 5 and which hold the wafer W at the tip of the rotation and expansion and contraction portion 113 I have. The blades 114a and 114b are attached to the rotation / extension portion 113 so as to face opposite directions. The inside of the transport chamber 5 is maintained at a predetermined degree of vacuum.

A HEPA filter (not shown) is provided on the ceiling of the loading / unloading chamber 8. Clean air, which has passed through the HEPA filter and has been removed from organic matter or particles, is supplied into the loading / unloading chamber 8 in a downflow state. Therefore, the wafer W is carried in and out in a clean air atmosphere at atmospheric pressure. Shutters (not shown) are provided in the three ports 9, 10, 11 for mounting the hoop F of the loading / unloading chamber 8, respectively. A Foup F accommodating the wafer W or accommodating the wafer W is directly attached to these ports 9 and 10 and the shutters are released when they are attached to prevent the entrance of the outside air into the loading / unloading chamber 8 As shown in Fig. In addition, an alignment chamber 115 is provided on the side surface of the loading / unloading chamber 8, so that alignment of the wafer W is performed.

A transfer device 116 is provided in the loading and unloading chamber 8 for loading and unloading the wafers W into and from the FOUP F and carrying the wafers W into and out of the load lock chambers 6 and 7. The transfer device 116 has two multi-joint arms and is structured to be able to travel on the rails 118 along the arrangement direction of the FOUP F. The transfer of the wafer W is carried out by placing the wafer W on the hand 117 at the front end. 12 shows a state in which one hand 117 is present in the loading / unloading chamber 8 and the other hand is inserted in the FOUP F. As shown in FIG.

The components (for example, the etching apparatus PM1, the film forming apparatus PM2, the processing apparatuses PM3 and PM4, the load lock chambers 6 and 7, and the transport apparatuses 112 and 116) of the processing system 100 are connected to a computer And is controlled by being connected to the control unit 120. [ The control unit 120 is also connected to a user interface 121 composed of a keyboard for an operator to input a command or the like for managing the system or a display for visualizing and displaying the operating status of the system.

The control unit 120 is also provided with a control program for realizing the various processes shown in Fig. 2 executed by the system under the control of the control unit 120, and a program for executing processes to the respective constituent units ) Is stored in the storage unit 122. [0051] The process recipe is stored in the storage medium in the storage unit 122. [ The storage medium may be a hard disk, a portable storage medium such as a CD ROM, a DVD, a flash memory, or the like. Further, the recipe may be appropriately transmitted from another apparatus, for example, via a dedicated line.

The processing in the processing system 100 is performed by calling an arbitrary processing recipe from the storage unit 122 and executing the processing recipe to the control unit 120, for example, by an instruction from the user interface 121. [ Further, the control unit 120 may directly control the respective constituent units, or the controllers may be separately provided in the respective constituent units and controlled through them.

In the processing system 100 according to the embodiment of the present invention, the hoop F is loaded first. Then, one wafer W is taken out from the FOUP F and brought into the alignment chamber 115 to align the wafer W. Subsequently, the wafer W is carried into any one of the load lock chambers 6 and 7 to bring the inside of the load lock chamber into a vacuum state. The wafer W in the load lock chamber is taken out by the transfer device 112 in the transfer chamber 5 and the wafer W is brought into the etching device PM1 and the etching process in steps ST1 and ST2 is performed.

The processed wafer W is taken out of the etching apparatus PM1 by the transfer device 112 and brought into the film forming apparatus PM2. The film forming apparatus PM2 deposits a fluid organic film 106 having a thickness of 4 nm or more on the Cu wiring 102 and the TiN film 105 of the wafer W by the film forming method according to the present embodiment. Thereafter, the wafer W is taken out by the transfer device 112, and the wafer W is brought into one of the load lock chambers 6 and 7 by the transfer device 112, and the inside of the wafer W is returned to the atmospheric pressure. The wafer W in the load lock chamber is taken out by the transfer device 116 in the loading and unloading chamber 8 and accommodated in any one of the FOUP F. The FOUP F is returned to the next process.

As described above, in the case of the In-system, the wafer W is transferred to the next path. (c) the load lock chambers 6 and 7 → (d) the transfer chamber 5 → (e) the etching apparatus PM1 (etching) → (b) (f) transport chamber 5 → (g) film forming apparatus PM2 (fluid organic film) → (h) transport chamber 5 → (i) load lock chamber 6, 7 → (j) 8)? (K) Hoop (F)? Next step

During the transportation, the wafer W is transported under the atmospheric environment and exposed to the atmosphere in (a) to (c) and (i) to (k). In this embodiment, however, the Cu wiring 102 and the TiN film 105 of the mask exposed in the etching process (e) performed by the etching apparatus PM1 are (g) the film formed by the film forming apparatus PM2 And is coated by a flowable organic film in the process. Further, the wafer W is vacuum-transferred to the atmosphere between the film forming apparatuses (e), (e), (g), (g)

Therefore, even if the wafer W is transported under the atmospheric environment and exposed to the atmosphere in (i) to (k), the flowable organic film becomes a protective film, and the Cu wiring 102 and the TiN film 105 are moisture Can be prevented. As a result, corrosion of the Cu wiring 102 and the TiN film 105 formed on the wafer W can be prevented.

In this embodiment, the fluid organic film in step ST3 may be formed in the same chamber as the chamber in which the etching process of steps ST1 and ST2 is performed in-situ. For example, in the processing system 100 of FIG. 12, the etching process and the film formation process may be performed continuously in the processing device PM3.

In this case, the wafer W is transported to the next path.

(a) hoop F → b loading and unloading chamber 8 c load lock chamber 6 d transfer chamber 5 processing unit PM3 etching + (I) the load lock chambers 6 and 7 → (j) the loading and unloading chamber 8 → (k) the hoop F → the next process

Even in this path, even if the wafer W is transported under the atmospheric environment and exposed to the atmosphere in (i) to (k), the flowable organic film becomes a protective film, and the Cu wiring 102 and the TiN film 105 It is possible to prevent the reaction with moisture. As a result, corrosion of the Cu wiring 102 and the TiN film 105 formed on the wafer W can be prevented.

As described above, the processing system 100 according to the present embodiment includes a plasma processing apparatus capable of forming an etching apparatus and a fluid organic film forming apparatus (In-system) in the system, or capable of performing both etching and a fluid organic film In-situ). Thus, the precursor generated from the gas of the low vapor-pressure material of the carbon-containing gas can be deposited from the bottom of the concave portion formed in the wafer W without exposing the metal film exposed by the etching to the atmosphere. Accordingly, Q-time can be managed by forming a fluid organic film on the wafer W and capping the metal film.

[Configuration Example of Plasma Processing Apparatus]

Next, an example of the configuration of the plasma processing apparatus arranged in the processing system according to the present embodiment will be described with reference to Fig. 13 is an example of the configuration of the plasma processing apparatus according to the present embodiment. The plasma processing apparatus according to the present embodiment functions as an etching apparatus that performs etching in steps ST1 and ST2 in FIG. 2 and a film forming apparatus that performs film formation in step ST3.

In this embodiment, as an example of the plasma processing apparatus, an inductively coupled plasma (ICP) processing apparatus 200 will be described as an example.

The inductively coupled plasma processing apparatus 200 is configured as a plasma processing apparatus using a flat coil type RF antenna and has a cylindrical vacuum chamber 10 made of metal such as aluminum or stainless steel. The chamber 10 is securely grounded.

A disk-shaped stage 12, in which a semiconductor wafer (hereinafter referred to as &quot; wafer W &quot;) is disposed as a substrate to be processed as a substrate to be processed, Respectively. The stage 12 is made of, for example, aluminum and is supported by an insulating tubular support portion 14 extending from the bottom of the chamber 10 to a vertical upper side.

An annular exhaust passage 18 is formed between the inner surface of the chamber 10 and the conductive cylindrical support 16 extending from the bottom of the chamber 10 to the vertical upper side along the outer periphery of the insulating tubular support portion 14 have. An annular baffle plate 20 is attached to the upper or inlet of the exhaust passage 18 and an exhaust port 22 is provided at the bottom. In order to make the flow of the gas in the chamber 10 uniform in the axisymmetric manner with respect to the wafer W on the stage 12, it is preferable that a plurality of the exhaust ports 22 are provided at regular intervals in the circumferential direction.

An exhaust device 26 is connected to each exhaust port 22 through an exhaust pipe 24. The exhaust device 26 has a vacuum pump such as a turbo molecular pump and can reduce the plasma processing space in the chamber 10 to a desired degree of vacuum. A gate valve 28 for opening and closing the loading and unloading port 27 of the wafer W is attached to the outside of the side wall of the chamber 10.

The second high frequency power source 30 is electrically connected to the stage 12 through the matching device 32 and the power feeding bar 34. [ The second high frequency power source 30 is capable of outputting a high frequency power LF for bias attraction of a constant frequency (for example, 400 kHz) suitable for controlling the energy of the ions drawn into the wafer W with a variable power have. The matching device 32 accommodates a reactance variable matching circuit for matching between the impedance on the side of the second high frequency power supply 30 and the impedance on the side of the load (mainly the stage, the plasma, and the chamber). And a blocking capacitor for generating a magnetic bias is included in the matching circuit.

An electrostatic chuck 36 for holding the wafer W with an electrostatic attraction force is provided on the upper surface of the stage 12 and a focus ring 36 surrounding the periphery of the wafer W is provided on the outer peripheral side of the electrostatic chuck 36. [ (Not shown). The electrostatic chuck 36 is formed by sandwiching an electrode 36a made of a conductive film between a pair of insulating films 36b and 36c and a high voltage direct current power source 40 is connected to the electrode 36a via a switch 42 and a cap 43 As shown in Fig. The wafer W can be held on the electrostatic chuck 36 by electrostatic force by the DC current supplied from the DC power supply 40.

In the interior of the stage 12, for example, an annular coolant chamber or a coolant passage 44 extending in the circumferential direction is provided. A coolant, for example, cooling water cw at a predetermined temperature is circulated through the piping 46, 48 from the chiller unit to the refrigerant passage 44. The temperature during processing of the wafer W on the electrostatic chuck 36 can be controlled by the temperature of the coolant. In this connection, a heat transfer gas, for example, He gas from the heat transfer gas supply unit is supplied between the upper surface of the electrostatic chuck 36 and the back surface of the wafer W through the gas supply pipe 50. Further, a lift pin capable of vertically moving the stage 12 to vertically move for loading / unloading the wafer W, and a lift mechanism thereof are also provided.

Next, the configuration of each part related to the plasma generation in the inductively-coupled plasma processing apparatus 200 will be described. In the ceiling of the chamber 10, a circular dielectric window 52 made of, for example, a quartz plate is hermetically attached at a relatively large distance from the stage 12. A coil-shaped RF antenna 54 is disposed horizontally on the dielectric window 52 coaxially with the chamber 10 or the stage 12. The RF antenna 54 preferably has a form of, for example, a spiral coil or a concentric circle having a constant radius within each circle, and is fixed on the dielectric window 52 by an antenna fixing member made of an insulator .

An output terminal of the first high frequency power source 56 is electrically connected to one end of the RF antenna 54 through a matching device 58 and a feeder line 60. The other end of the RF antenna 54 is electrically connected to the ground potential through a ground line.

The first high frequency power supply 56 is capable of outputting a plasma generating high frequency HF having a frequency (for example, 27 MHz or more (60 MHz or the like)) suitable for generation of plasma by high frequency discharge with variable power. The matching device 58 accommodates a reactance variable matching circuit for matching between the impedance of the first high frequency power source 56 side and the impedance of the load side (mainly the RF antenna, the plasma, and the correction coil).

The gas supply for supplying a predetermined gas to the processing space in the chamber 10 is an annular manifold or buffer installed in (or outside) the sidewall of the chamber 10 at a location somewhat lower than the dielectric window 52, A plurality of sidewall gas discharge holes 64 facing the plasma generation space S from the buffer portion 62 at regular intervals in the circumferential direction and a plurality of sidewall gas discharge holes 64 extending from the gas supply source 66 to the buffer portion 62 And has an extended gas supply pipe 68. The gas supply source 66 includes a flow controller and an on-off valve.

The control unit 74 includes a microcomputer and is connected to various units in the inductively coupled plasma processing apparatus 200 such as an exhaust unit 26, a second high frequency power source 30, a first high frequency power source 56, the matching unit 32, the matching unit 58, the switch 42 for the electrostatic chuck, the gas supply source 66, the chiller unit, the heating gas supply unit, and the like.

In order to form the film in the inductively coupled plasma processing apparatus 200, the gate valve 28 is first opened to bring the wafer W to be processed into the chamber 10 and the electrostatic chuck 36, . After the gate valve 28 is closed, the predetermined gas is supplied from the gas supply source 66 through the gas supply pipe 68, the buffer unit 62, and the sidewall gas discharge hole 64 at a predetermined flow rate and flow rate, (10), and the pressure in the chamber (10) is set to a set value by the exhaust device (26). The first RF power supply 56 is turned on to output a plasma generating high frequency HF with a predetermined RF power and the RF antenna 54 is supplied with power of high frequency HF through the matching device 58 and the feed line 60 .

On the other hand, when the power of the high frequency LF for ion attraction control is applied, the second high frequency power supply 30 is turned on to output the high frequency power LF and the power of the high frequency LF is supplied to the matching device 32 and the power supply rod 34 To the stage 12 through the contact hole (not shown). In the case of not applying the power of the high frequency LF for ion attraction control, the high frequency power is set to 0 W. The electrothermal gas is supplied from the electrostatic chuck 36 to the contact interface between the electrostatic chuck 36 and the wafer W and the electrostatic chuck 36 is turned on by the electrostatic chuck 36 by turning on the switch 42, Shielding at the contact interface.

The predetermined gas discharged from the side wall gas discharge hole 64 is uniformly diffused into the processing space below the dielectric window 52. [ An RF magnetic field passing through the dielectric window 52 and passing through the plasma generating space S in the chamber is generated around the RF antenna 54 by the current of the high frequency HF flowing through the RF antenna 54, The RF induced electric field is generated in the azimuth direction of the processing space due to the temporal change of the RF magnetic field. Then, electrons accelerated in the azimuth direction by the induced electric field cause ion collision with molecules or atoms of the supplied gas, and a donut-shaped plasma is generated. The radicals and ions of the donut-type plasma are diffused in four directions in a wide processing space, the radicals are poured downward in the backward direction, and the ions are supplied to the upper surface of the wafer W . In this manner, the active species of the plasma brings chemical reaction and physical reaction on the surface of the wafer W, and the processed film is etched in a desired pattern.

The inductively coupled plasma processing apparatus 200 generates the inductively coupled plasma under the dielectric window 52 close to the RF antenna 54 as described above and the donut type plasma is applied to the inside of the wide processing space And the density of the plasma is averaged near the stage 12 (that is, on the wafer W). Here, the density of the donut-shaped plasma depends on the strength of the induced electric field, and furthermore, on the magnitude of the power of the high frequency HF (more precisely, the current flowing through the RF antenna 54) supplied to the RF antenna 54. That is, the higher the power of the high frequency HF, the higher the density of the donut-shaped plasma, and the density of the plasma near the stage 12 through the diffusion of the plasma becomes higher as a whole. On the other hand, the shape in which the donut-shaped plasma is diffused in four directions (particularly in the radial direction) mainly depends on the pressure in the chamber 10, and as the pressure is lowered, more plasma is collected in the center of the chamber 10, The plasma density distribution tends to rise at the center. In addition, the plasma density distribution in the donut-shaped plasma may change depending on the power of the high-frequency HF supplied to the RF antenna 54, the flow rate of the process gas introduced into the chamber 10, and the like.

Here, the &quot; Donut type plasma &quot; is not limited to a strictly ring-like plasma in which the plasma is not radially inward (radially inward) in the radial direction of the chamber 10 but only in the radially outer side, Means that the plasma has a larger volume or density in the radially outer side than in the radially inner side. Depending on the conditions such as the kind of gas used for the processing gas and the value of the pressure in the chamber 10, the term &quot; donut type plasma &quot;

The control unit 74 has a CPU, a ROM (Read Only Memory), and a RAM (Random Access Memory), which are not shown in the drawing. The control unit 74 controls the inductively coupled plasma processing apparatus 200, and controls the semiconductor manufacturing method according to the present embodiment.

The inductively coupled plasma processing apparatus 200 having such a configuration can perform at least one of an etching process and a film forming process.

The plasma processing apparatus for implementing the semiconductor manufacturing method according to the present embodiment includes an inductively coupled plasma processing apparatus (ICP apparatus) and a capacitively coupled plasma processing apparatus for applying high-frequency power for plasma generation to the upper electrode side Two-frequency CCP apparatus), and may be any of a microwave plasma processing apparatus and a remote plasma processing apparatus.

As described above, according to the semiconductor manufacturing method of the present embodiment, it is possible to prevent the corrosion of the metal on the object to be processed in semiconductor manufacturing.

The semiconductor manufacturing method and the plasma processing apparatus according to the present invention are not limited to the above embodiments and various modifications and improvements can be made within the scope of the present invention. It is possible. The matters described in the plural embodiments can be combined within a range that does not contradict each other.

For example, although the wafer W has been described as an example of the object to be processed in this specification, the object to be processed is not limited to this, and various substrates used for an LCD (Liquid Crystal Display) or an FPD (Flat Panel Display) , A CD substrate, or a printed substrate.

In the embodiment of the present invention, a case where a metal such as Cu is used as the conductive layer on the wafer W has been described, but the present invention is not limited thereto. As the conductive layer, for example, a metal such as ruthenium (Ru), a silicide including nickel (Ni), cobalt (Co), carbon (C), doped silicon in which boron (B) Polycrystalline silicon, amorphous silicon, and silicon germanium (SiGe).

1: SiN film
2: SiO ₂ film
3: organic film
4: Si-ARC
5: Carrier
6, 7: load lock room
10: chamber
12: stage
20: Baffle plate
26: Exhaust system
30: Second high frequency power source
36: electrostatic chuck
40: DC power source
44: refrigerant passage
52: Dielectric window
54: RF antenna
56: first high frequency power source
64: Side wall gas discharge hole
66: gas supply source
74:
100: Processing system
101: wiring layer
102: Cu wiring
103: liner film
104: Interlayer insulating film
105: TiN film
106: fluid organic film
200: Inductively Coupled Plasma Processing Device
H: Via hole
PM1: etching apparatus
PM2: Deposition device

Claims (11)

A first step of etching the insulating film on the conductive layer of the object to be processed with a pattern of a mask and exposing the conductive layer to a recess of the insulating film;
And a second step of forming an organic film in a concave portion of the insulating film from which the conductive layer is exposed,
In the second step,
A step of holding the interior of the chamber at a predetermined pressure, cooling the stage to a cryogenic temperature of -20 占 폚 or less and placing the object to be processed on the stage,
Supplying a gas containing a gas of a low vapor pressure material into the chamber;
Forming a plasma from a gas containing the gas of the supplied low vapor pressure material and depositing a precursor generated from the low vapor pressure material by the plasma on a concave portion of the insulating film to form the organic film
And a semiconductor layer. The method of claim 1, wherein the first process and the second process are performed in different chambers,
Wherein the object to be processed is transported under a vacuum environment between one chamber for executing the first process and another chamber for executing the second process. The semiconductor manufacturing method according to claim 1, wherein the first process and the second process are performed in the same chamber. The semiconductor manufacturing method according to any one of claims 1 to 3, wherein the second step forms the organic film having a fluidity of a film thickness of 4 nm or more. 4. The method according to any one of claims 1 to 3, wherein the mask comprises a metal,
Wherein the organic film is formed so as to cover the mask. 5. The cleaning method according to claim 4, wherein after the second step is performed, the object to be processed is transported to the cleaning device under an atmospheric environment,
Wherein the cleaning device removes the organic film. The method of manufacturing a semiconductor according to any one of claims 1 to 3, wherein the gas of the low vapor-pressure material is a gas which becomes a vapor pressure at a temperature higher than a temperature indicated by a vapor pressure curve of C ₄ F ₈ . 8. The method of claim 7, wherein the gas of the low vapor pressure material is a carbon-containing gas. The method of claim 8, wherein the gas of the low vapor pressure material is any one of C ₄ F ₈ , C ₄ F ₆ , and isopropyl alcohol (IPA). The semiconductor manufacturing method according to any one of claims 1 to 3, wherein the conductive layer includes a metal film or a conductive silicon-containing film. 1. A plasma processing apparatus comprising a stage for disposing an object to be processed, a gas supply unit for supplying gas, and a control unit,
Wherein,
The insulating film on the conductive layer of the object to be processed is etched in the pattern of the mask, the conductive layer is exposed in the recess of the insulating film formed,
An organic film is formed on the concave portion of the insulating film from which the conductive layer is exposed,
In the formation of the organic film,
The inside of the chamber is maintained at a predetermined pressure, the stage is cooled to a cryogenic temperature of -20 DEG C or lower, an object to be processed is placed on the stage,
Supplying a gas containing a gas of a low vapor pressure material into the chamber,
A plasma is generated from a gas containing the gas of the supplied low vapor pressure material and a precursor generated from the low vapor pressure material by the plasma is deposited on the concave portion of the insulating film to control the formation of the organic film / RTI &gt;

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