JP6501576B2 - Method and apparatus for forming silicon film - Google Patents

Description

  The present invention relates to a method of forming a silicon film and a film forming apparatus.

  Silicon films are widely used, for example, as semiconductors / conductors, hard masks, etc. in the field of manufacturing semiconductor integrated circuit devices. The silicon film is formed not only on a flat surface to be processed but also on a surface to be processed having asperities. For example, it has a hole shape having a longitudinally long cross-sectional shape such as a trench, a via, or a groove. It is also used as an embedding material for line-shaped parts. For example, filling the inside of the groove with a silicon film is described in, for example, Patent Document 1.

JP, 2012-4542, A

  In semiconductor integrated circuit devices, for example, three-dimensional structuring of devices is in progress for further improvement of the degree of integration. As the three-dimensional structure of the device progresses, the depth of a recess represented by a trench, a via, a trench and the like becomes deeper. And since the processing minimum line width is also shrunk, the aspect ratio of the above-mentioned crevice will keep increasing (high aspect ratio).

  In addition, the structure of the device is also complicated. Depending on the device, there is also a process of removing the silicon film embedded in the recess by dry etching.

  However, if the aspect ratio of the recess is increased and the minimum line width of the recess is further narrowed, removal of the silicon film becomes difficult. For this reason, there existed a situation that the residue of a silicon will generate | occur | produce at the bottom of the said recessed part.

  The present invention forms a silicon film which can be easily removed from the recess even if the aspect ratio of the recess represented by the trench, the via, the trench, etc. is increased and the minimum line width is reduced. Provided are a method and a film forming apparatus capable of implementing the film forming method.

A silicon film forming method according to an aspect of the present invention is a silicon film forming method for forming a silicon film on a surface to be processed of an object to be processed, the method comprising: (1) the object to be processed; Performing a process of reducing the adhesion between the silicon film to be formed and the surface to be treated with respect to the treated surface; (2) the object to which adhesion with the silicon film to be deposited is reduced Supplying a silicon source gas to the treated surface, forming a silicon film on the treated surface, and the (1) step includes (II) a halogen-based gas in the treated surface The step of supplying the gas, (III) the step of supplying the gas containing the NH ₃ gas and the HF gas, the step (IV) supplying the gas containing the NH ₃ gas and the HF gas, and then the gas containing the NH ₃ gas It is any one process of heat processing while doing .

  A film forming apparatus according to a second aspect of the present invention is a film forming apparatus for forming a silicon film on a surface to be processed of an object to be processed, wherein the processing chamber accommodates the object to be processed; A processing gas supply mechanism for supplying a gas used for processing in a chamber, a heating device for heating the object to be treated accommodated in the processing chamber, the processing gas supply mechanism, and a controller for controlling the heating device And the controller controls the processing gas supply mechanism and the heating device such that the method for forming a silicon film according to the first aspect is performed.

  According to the present invention, the silicon film can be easily removed from the recess even if the aspect ratio of the recess represented by the trench, the via, the trench and the like is increased and the minimum line width is reduced. It is possible to provide a film forming method and a film forming apparatus capable of performing the film forming method.

Flow chart showing an example of the sequence of the method of forming a silicon film according to the first embodiment of the present invention FIG. 2 is a cross sectional view schematically showing the state of the object in the sequence shown in FIG. FIG. 2 is a cross sectional view schematically showing the state of the object in the sequence shown in FIG. FIG. 2 is a cross sectional view schematically showing the state of the object in the sequence shown in FIG. FIG. 2 is a cross sectional view schematically showing the state of the object in the sequence shown in FIG. FIG. 2 is a cross sectional view schematically showing the state of the object in the sequence shown in FIG. Sectional view schematically showing how a silicon film is removed according to a reference example Sectional view schematically showing how a silicon film is removed according to a reference example Sectional view schematically showing the state of removal of the silicon film formed by the first embodiment Sectional view schematically showing the state of removal of the silicon film formed by the first embodiment Sectional view schematically showing the state of removal of the silicon film formed by the first embodiment Sectional view schematically showing the state of removal of the silicon film formed by the first embodiment Sectional view schematically showing the state of removal of the silicon film formed by the first embodiment Diagram showing destruction energy (adhesion strength) K _IC Diagram for explaining the aspect ratio of the recess Sectional view schematically showing an example of a vertical batch-type film forming apparatus according to a second embodiment of the present invention

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that common parts are denoted by common reference symbols throughout the drawings.

First Embodiment
<Method of forming silicon film>
FIG. 1 is a flow chart showing an example of the sequence of the method for forming a silicon film according to the first embodiment of the present invention, and FIGS. 2A to 2C schematically show the states of the object in the sequence shown in FIG. FIG.

First, as shown in step 1 in FIG. 1, the object to be processed is carried into the processing chamber of the film forming apparatus. As a to-be-processed object, as shown to FIG. 2A, the silicon wafer (henceforth a wafer) 1 is prepared, for example. In the wafer 1 of this example, a silicon oxide film, for example, an SiO ₂ film 2 is formed on the surface, and a silicon film 3 is formed on the SiO ₂ film 2. For example, a trench 4 is formed in the silicon film 3 as a recess. Further, a silicon oxide film, for example, an SiO ₂ film 5 is formed on the surface of the silicon film 3 including the side wall of the trench 4. The processing surface of the wafer 1 is the surface on which the trench 4 is present. Therefore, the surface to be processed in this example is a silicon oxide such as the SiO ₂ film 2 or the SiO ₂ film 5 exposed at the bottom of the trench 4.

Next, as shown in step 2 in FIG. 1 and FIG. 2B, the adhesion between the silicon film to be formed and the surface to be processed is to the object to be processed, in this example, the surface to be processed of the wafer 1. Perform processing to reduce. As a result, the surfaces of the SiO ₂ film 2 and the SiO ₂ film 5 exposed at the bottom of the trench 4 become the processed surface 6 with reduced adhesion as shown by the broken line. As a process which reduces adhesiveness, five processes of following (I)-(V) can be mentioned.

(I) Supply a gas containing hydrocarbon gas to the surface to be treated
(II) Supply a gas containing a halogen-based gas to the surface to be treated
(III) Supply a gas containing NH ₃ gas and HF gas to the surface to be treated (COR treatment)
(IV) After supplying a gas containing NH ₃ gas and HF gas to the surface to be treated (COR process), annealing is performed while supplying a gas containing NH ₃ gas to the surface to be treated
(V) Supplying a gas containing a substance to be a raw material of the adhesion reduced layer to the surface to be treated. Examples of treatment conditions for each of the treatments (I) to (V) are as follows.

(I) An example of supplying a gas containing a hydrocarbon gas is
Hydrocarbon gas: C ₂ H ₄ gas
C ₂ H ₄ gas flow rate: 190 sccm
Processing time: 15min
Processing temperature: 530 ° C
Processing pressure: 133.3 Pa (1 Torr)
(In this specification, 1 Torr is defined as 133.3 Pa)
It is.

(II) An example of supplying a gas containing a halogen-based gas is
Halogen gas: Cl ₂ gas
Dilution gas: N ₂ gas
N ₂ / Cl ₂ gas _{flow: N 2 / Cl 2 = 1350} / 230sccm
Processing time: 15min
Processing temperature: 300 ° C
Processing pressure: 399.9 Pa (3 Torr)
It is.

(III) An example of performing COR processing is
NH ₃ gas flow rate: 1350 sccm
HF gas flow rate: 40 sccm
Dilution gas: N ₂ gas
N ₂ gas flow rate: 200 sccm
Processing time: 15min
Processing temperature: 150 ° C
Processing pressure: 266.6 Pa (2 Torr)
It is.

(IV) An example of annealing with NH ₃ gas after COR processing is
<< COR >>
NH ₃ gas flow rate: 1350 sccm
HF gas flow rate: 40 sccm
Dilution gas: N ₂ gas
N ₂ gas flow rate: 200 sccm
Processing time: 15min
Processing temperature: 150 ° C
Processing pressure: 266.6 Pa (2 Torr)
<< Annealing >>
NH ₃ gas flow rate: 230 sccm
Processing time: 30min
Processing temperature: 450 ° C
Processing pressure: 533.2 Pa (4 Torr)
It is.

(V) An example in the case of supplying a gas containing a substance to be a raw material of the adhesion lowering layer is
Gas containing material that is the source of adhesion reduction layer: C ₄ H ₆ gas
C ₄ H ₆ gas flow rate: 100 sccm
Halogen gas: Cl ₂ gas
Cl ₂ gas flow rate: 50 sccm
Processing time: 180 min
Processing temperature: 350 ° C
Processing pressure: 199.95 Pa (1.5 Torr)
It is. In the present example, the gas containing a substance to be a raw material of the adhesion reduction layer is a hydrocarbon-based gas. For this reason, a carbon layer is formed on the surface to be treated as an adhesion reducing layer. One of the reasons for adding a halogen-based gas to a hydrocarbon-based gas is to lower the thermal decomposition temperature of the hydrocarbon-based gas. The halogen-based gas may be added as needed.

  Next, as shown in step 3 in FIG. 1 and in FIG. 2C, silicon source gas is supplied to the surface 6 to be treated with reduced adhesion, and a silicon film is formed on the surface 6 to be treated. A silicon film 7 is formed. Thereby, the trench 4 is filled with the amorphous silicon film 7.

An example of processing conditions in step 3 is
Silicon source gas: SiH ₄ gas
SiH ₄ gas flow rate: 300 sccm
Processing time: 110 min
Processing temperature: 530 ° C
Processing pressure: 53.3 Pa (0.4 Torr)
It is.

  In addition, when the process which reduces adhesiveness is process (I)-(IV), it will be in the state to which the halogen and the organic substance adhered, for example. As a result of the treated surface being in such a state, the treated surface 6 has reduced adhesion. Then, when any of the processes (I) to (IV) is performed in step 2 shown in FIG. 1, as shown in FIG. 2C, an amorphous silicon film is formed on the surface 6 to be treated with reduced adhesion. 7 is deposited.

In the case of the treatment (V), as shown in FIG. 3A, a thin carbon layer 6a is formed as an adhesion decreasing layer on the surface to be treated, in this example, the surfaces of the SiO ₂ film 2 and the SiO ₂ film 5. It is formed. The thin carbon layer 6a formed on the surface to be treated is mainly composed of easily cleavable graphite and is amorphous even if the bond between amorphous silicon and carbon and / or the bond between carbon and SiO ₂ is strong. The adhesion between the silicon film 7 and the surface to be treated, in this example, the SiO ₂ films 2 and 5 can be reduced. Further, the adhesion lowering layer is not limited to carbon, and may be made of a substance having a cleaving property or a substance having a property of being easily broken such as fracture.

  According to the silicon film thus formed, for example, the amorphous silicon film 7, the following advantages can be obtained.

<In the case of reference example>
FIG. 4A and FIG. 4B are cross-sectional views schematically showing how the silicon film is removed according to the reference example.

As shown in FIG. 4A, when the aspect ratio of the trench 4 is increased and the minimum line width T _CD of the trench 4 is narrowed, removal of the amorphous silicon film 7 becomes difficult. For this reason, when the treatment for reducing the adhesion to the surface to be processed is not performed, the silicon residue 7 a is easily generated at the bottom of the trench 4 when the amorphous silicon film 7 is removed from the surface to be processed.

Assuming that the etching conditions for the amorphous silicon film 7 are made more severe in order to suppress the generation of such residues 7 a, the damage layer 2 a on the surface of the SiO ₂ film 2 exposed at the bottom of the trench 4 as shown in FIG. Will occur. The occurrence of the damaged layer 2a lowers the performance of the device, widens the variation in quality, and lowers the yield.

<In the case of the first embodiment>
5A to 5D and 6 are cross-sectional views schematically showing the state of removal of the silicon film formed according to the first embodiment.

With respect to such a reference example, according to the method for forming a silicon film of the first embodiment, the adhesion to the surface to be processed is reduced. Therefore, as shown in FIG. 5A, as the silicon residue 7a has occurred, as shown in FIG. 5B, for example, residue 7a is detached from the SiO ₂ film 2 and 5 to be processed surface.

  The peeled residue 7a is further finely divided by an etchant as shown by reference numeral 7b in FIG. 5C, and is exhausted from the inside of the trench 4 to the outside as shown in FIG. 5D.

  Further, as shown in FIG. 6, when the thin carbon layer 6a is formed on the surface to be treated, the residue 7a is peeled off from the surface to be treated together with the thin carbon layer 6a, for example.

  As described above, according to the amorphous silicon film 7 formed according to the first embodiment, the adhesion to the surface to be processed is reduced. Therefore, it is possible to obtain an advantage that even when the reduction of the high aspect ratio and the minimum line width of the recess represented by the trench 4 progresses, it can be easily removed from the recess. Such an amorphous silicon film 7 is effective for application as a protective material for filling the recess formed on the surface to be treated, for example, the trench 4 and protecting the trench 4 formed on the surface to be treated.

<M-ELT analysis result>
FIG. 7 is a view showing a breaking energy (adhesive strength) K _IC . FIG. 7 shows reference examples and cases of processes (I) to (V). The “APM” described in the figure is “W / O” when APM cleaning is performed on the surface to be treated (the surface of the SiO ₂ film 2 and the SiO ₂ film 5) before forming the amorphous silicon film. Indicates a case where APM cleaning was not performed.

The destruction energy K _IC was determined by the m-ELT (modified Edge Liftoff Test) method. In the m-ELT method, an amorphous silicon film is formed on a SiO ₂ film, and an epoxy resin is applied on the amorphous silicon film. Next, the epoxy resin is cured to shrink the epoxy resin, and the degree of peeling of the amorphous silicon film from the SiO ₂ film is examined.

(Reference example)
As shown in FIG. 7, in the case of the reference example in which the treatment for reducing the adhesion to the surface to be treated is not performed, the breaking energy K _IC of the amorphous silicon film 7 is
APM: Average value about 0.43MPa · m ^1/2
W / O: Average value about 0.41MPa · m ^1/2
Met. When the breaking energy K _IC is large, the adhesion between the amorphous silicon film and the SiO ₂ film is strong and it tends to be difficult to peel off. On the contrary, when the value is small, the adhesion is weak and peeling off Indicates that they tend to do so. Therefore, when the breaking energy K _IC falls below these values, the adhesion between the amorphous silicon film and the SiO ₂ film is reduced.

(I) In the case of supplying gas containing hydrocarbon gas Hydrocarbon gas: C ₂ H ₄
APM: Average value about 0.44MPa · m ^1/2 (+ about 0.01MPa · m ^1/2 )
W / O: Average value about 0.37MPa · m ^1/2 (-about 0.04MPa · m ^1/2 )
In the treatment (I), the adhesion between the amorphous silicon film and the SiO ₂ film was improved in “APM”, but the adhesion was decreased in “W / O”.

(II) When supplying a gas containing a halogen-based gas Halogen-based gas: Cl ₂
APM: Average value about 0.44MPa · m ^1/2 (+ about 0.01MPa · m ^1/2 )
W / O: The average value of about 0.39MPa ^{· m 1/2} (- about 0.02MPa ^{· m 1/2)}
In the treatment (II), as in the treatment (I), the adhesion between the amorphous silicon film and the SiO ₂ film was improved by “APM”, and the adhesion was lowered by “W / O”.

(III) When performing COR processing COR gas: NH ₃ + HF (dilution gas: N ₂ )
APM: Average value about 0.40MPa · m ^1/2 (-about 0.03MPa · m ^1/2 )
W / O: The average value of about 0.39MPa ^{· m 1/2} (- about 0.02MPa ^{· m 1/2)}
In the treatment (III), the adhesion between the amorphous silicon film and the SiO ₂ film decreased in both “APM” and “W / O”.

(IV) When annealing with NH ₃ gas after COR processing COR gas: NH ₃ + HF (dilution gas: N ₂ )
Annealing gas: NH ₃
APM: Average value about 0.40MPa · m ^1/2 (-about 0.03MPa · m ^1/2 )
W / O: The average value of about 0.39MPa ^{· m 1/2} (- about 0.02MPa ^{· m 1/2)}
Also in the treatment (IV), as in the treatment (III), the adhesion between the amorphous silicon film and the SiO ₂ film was lowered in both “APM” and “W / O”. The difference between the treatment (III) and the treatment (IV) is that, for example, the treatment (IV) is annealed with NH ₃ gas after the COR treatment, so the surface to be treated is compared with the treatment (III) not annealed Can improve the "roughness" of

(V) In the case of supplying a gas containing a material to be a material for the adhesion reduction layer A gas containing a material to be a material for the adhesion reduction layer: C ₄ H ₆ gas Halogen gas: Cl ₂ gas
APM: Average value about 0.135 MPa · m ^1/2 (-about 0.295 MPa · m ^1/2 )
W / O: The average value of about 0.13MPa ^{· m 1/2} (- about 0.28MPa ^{· m 1/2)}
In the case of (V), the adhesion between the amorphous silicon film and the SiO ₂ film significantly decreased to about 0.3 MPa · m ^1/2 in both “APM” and “W / O”.

Thus, in the silicon film formed according to the film forming method of the silicon film according to the first embodiment, the stress intensity factor analyzed by the m-ELT method that the adhesion with the surface to be treated is reduced. Also confirmed by K _IC .

When the treatment (I) and the treatment (II) are selected, if the surface to be treated, for example, the surface of the SiO ₂ film, is cleaned before the formation of the silicon film, the adhesion is improved. Also confirmed. For this reason, when the treatment (I) and the treatment (II) are selected, it is desirable not to clean the surface to be treated before the formation of the silicon film.

<Aspect ratio of recess>
Next, the aspect ratio of the recess suitable for applying the present invention will be described.

  FIG. 8 is a diagram for explaining the aspect ratio of the recess. In FIG. 8, the aspect ratio “b / a” is “5”, “10”, “20” and “30” when the diameter of the recess is “a” and the depth of the recess is “b”. The case is shown.

  As described above, according to the method for forming a silicon film according to the first embodiment of the present invention, the adhesion between the silicon film and the surface to be processed can be reduced. For this reason, as shown in FIG. 8, it is removed from the surface to be treated in the future on the surface to be treated on which a recess with a high aspect ratio having a finite value of aspect ratio “b / a = 10” or more is formed. It is effective for forming a silicon film that And even if the aspect ratio "b / a = 20" or more, and further the aspect ratio "b / a = 30" or more further advances, silicon according to the first embodiment of the present invention The film formation method of the film can be suitably applied.

  Also, the minimum line width of the recess is one of the important factors. For example, as the minimum line width a of the recess shown in FIG. 8 is reduced, it is difficult to remove the silicon film from the recess. Therefore, the silicon film forming method according to the first embodiment of the present invention is more preferably applied to, for example, a recess whose minimum line width a is reduced to “50 nm” or less. Therefore, in the method of forming a silicon film according to the first embodiment of the present invention, for example, the minimum line width a is a finite value of “50 nm” or less, or the aspect ratio is a finite value of “10” or more, This method is particularly effective when forming a silicon film on an object to be processed having a concave portion having an aspect ratio of “20” or more and a finite aspect ratio of “30” or more. .

<About treated gas>
Examples of hydrocarbon-based gases used for treatment (I) and treatment (V) are
C _n H _{2 n + 2} (A), or C _m H _{2 m} (B), or C _m H _{2 m-2} (C)
And a gas containing at least one of the hydrocarbon compounds represented by the molecular formula of
However, in formulas (A) to (C),
n is a natural number of "1" or more, and m is a natural number of "2" or more.

Also, for the above-mentioned hydrocarbon-based gas,
Benzene gas (C ₆ H ₆ )
May be included.

As hydrocarbon type gas represented by said (A) formula,
Methane gas (CH ₄ )
Ethane gas (C ₂ H ₆ )
Propane gas (C ₃ H ₈ )
Butane gas (C ₄ H ₁₀ : also includes other isomers)
Pentane gas (C ₅ H ₁₂ : also includes other isomers)
Etc. can be mentioned.

Moreover, as hydrocarbon type gas represented by said (B) Formula,
Ethylene gas (C ₂ H ₄ )
Propylene gas (C ₃ H ₆ : also includes other isomers)
Butylene gas (C ₄ H ₈ : also includes other isomers)
Pentengas (C ₅ H ₁₀ : also includes other isomers)
Etc. can be mentioned.

Moreover, as hydrocarbon gas represented by said (C) Formula,
Acetylene gas (C ₂ H ₂ )
Propine gas (C ₃ H ₄ : also includes other isomers)
Butadiene gas (C ₄ H ₆ : also includes other isomers)
Isoprene gas (C ₅ H ₈ : also includes other isomers)
Etc. can be mentioned.

As an example of the halogen-based gas used for the treatment (II) and the treatment (V), a gas containing a halogen element can be mentioned. As a halogen element,
Fluorine (F)
Chlorine (Cl)
Bromine (Br)
Iodine (I)
Can be mentioned.

In addition, when used in the treatment (V), these halogen elements are not supplied as a compound gas, but a single fluorine (F ₂ ) gas, a single chlorine (Cl ₂ ) gas, a single bromine (Br ₂ ) gas, And is preferably supplied as a single iodine (I ₂ ) gas. This is because if it is a compound gas of a halogen element, the temperature is required to thermally decompose the compound gas, which may affect the effect of lowering the thermal decomposition temperature of the hydrocarbon-based gas. is there. However, even in the case of supplying a halogen element as a compound gas, for example, as long as it is a compound of a halogen element and hydrogen such as HCl and HBr, it can be used without any problem in practical use. .

  Moreover, it is preferable to select chlorine from the viewpoint of handling safety.

Second Embodiment
<Deposition apparatus>
The second embodiment relates to an example of a film forming apparatus capable of performing the film forming method of a silicon film according to the first embodiment.

  FIG. 9 is a cross sectional view schematically showing an example of a vertical batch type film forming apparatus according to a second embodiment of the present invention. In addition, the vertical batch-type film-forming apparatus which concerns on an example implements process (V), for example.

  As shown in FIG. 9, the film forming apparatus 100 has a cylindrical processing chamber 101 with a ceiling, the lower end of which is opened. The entire processing chamber 101 is made of, for example, quartz. On the ceiling in the processing chamber 101, a quartz ceiling plate 102 is provided. At the lower end opening of the processing chamber 101, for example, a manifold 103 formed in a cylindrical shape by stainless steel is connected via a seal member 104 such as an O-ring.

  The manifold 103 supports the lower end of the processing chamber 101. From the lower side of the manifold 103, a vertical wafer boat 105 made of quartz capable of mounting a plurality of wafers, for example, 50 to 100 wafers 1 in the height direction as an object to be processed is inside the processing chamber 101. It can be inserted into the The vertical wafer boat 105 has a plurality of columns 106, and the grooves formed in the columns 106 support the plurality of wafers 1 in the height direction.

  The vertical wafer boat 105 is mounted on the table 108 through a heat insulating cylinder 107 made of quartz. The table 108 is supported on a rotating shaft 110 which opens and closes the lower end opening of the manifold 103, for example, through a lid 109 made of stainless steel. For example, a magnetic fluid seal 111 is provided at a penetrating portion of the rotating shaft 110, and the rotating shaft 110 is rotatably supported while being airtightly sealed. A seal member 112 made of, for example, an O-ring is interposed between the peripheral portion of the lid portion 109 and the lower end portion of the manifold 103. Thereby, the sealing performance in the processing chamber 101 is maintained. The rotating shaft 110 is attached to, for example, the tip of an arm 113 supported by an elevating mechanism (not shown) such as a boat elevator. Thus, the wafer boat 105, the lid 109, etc. are integrally lifted and lowered into and out of the processing chamber 101.

  The film forming apparatus 100 has a processing gas supply mechanism 114 for supplying a gas used for processing in the processing chamber 101, and an inert gas supply mechanism 115 for supplying an inert gas in the processing chamber 101. ing.

  The processing gas supply mechanism 114 includes a silicon source gas supply source 117a, a hydrocarbon-based gas supply source 117b, and a halogen-based gas supply source 117c.

In this example, the silicon source gas supply source 117a is a SiH ₄ gas as a silicon source gas, the hydrocarbon based gas supply source 117b is a C ₄ H ₆ gas as a hydrocarbon based gas, and the halogen based gas supply source 117c is a halogen based gas. As the gas, Cl ₂ gas is supplied into the processing chamber 101, respectively.

The inert gas supply mechanism 115 includes an inert gas supply source 120. The inert gas supply source supplies N ₂ gas into the processing chamber 101 as the inert gas.

  The silicon source gas supply source 117a is connected to the dispersion nozzle 123a via the flow rate controller 121a and the on-off valve 122a. Similarly, the hydrocarbon-based gas supply source 117b is connected to the dispersion nozzle 123b (not shown) via the flow controller 121b and the on-off valve 122b, and the halogen-based gas supply source 117c is similarly connected via the flow controller 121c and the on-off valve 122c. Are connected to the dispersion nozzles 123c. In FIG. 9, the dispersion nozzle 123b is not shown.

  The dispersion nozzles 123a to 123c are made of quartz tubes and penetrate the side wall of the manifold 103 inwards, are bent upward and extend vertically. A plurality of gas discharge holes 124a to 124c are formed at predetermined intervals in the vertical portions of the dispersion nozzles 123a to 123c. The silicon source gas, the hydrocarbon-based gas, and the halogen-based gas are respectively discharged substantially uniformly in the horizontal direction from the gas discharge holes 124 a to 124 c into the processing chamber 101.

  The inert gas supply source 120 is connected to the nozzle 128 via the flow rate controller 121 d and the on-off valve 122 d. The nozzle 128 penetrates the side wall of the manifold 103 and discharges the inert gas horizontally from the tip thereof into the processing chamber 101.

  An exhaust port 129 for exhausting the inside of the processing chamber 101 is provided in a portion of the processing chamber 101 opposite to the dispersion nozzles 123 a to 123 c. The exhaust port 129 is elongated by cutting the side wall of the processing chamber 101 in the vertical direction. At a portion corresponding to the exhaust port 129 of the processing chamber 101, an exhaust port cover member 130 having a U-shaped cross section so as to cover the exhaust port 129 is attached by welding. The exhaust port cover member 130 extends upward along the side wall of the processing chamber 101 and defines a gas outlet 131 above the processing chamber 101. An exhaust mechanism 132 including a vacuum pump and the like is connected to the gas outlet 131. The exhaust mechanism 132 exhausts the inside of the processing chamber 101 to set the exhaust of the processing gas used for the processing and the pressure in the processing chamber 101 as the processing pressure according to the processing.

  A cylindrical heating device 133 is provided on the outer periphery of the processing chamber 101. The heating device 133 activates the processing gas supplied into the processing chamber 101 and heats the object to be processed, which is the wafer 1 in this example, accommodated in the processing chamber 101.

  Control of each part of the film forming apparatus 100 is performed by, for example, a controller 150 including a microprocessor (computer). A user interface 151 is connected to the controller 150. The user interface 151 visualizes and displays the operation status of the film forming apparatus 100 and an input unit including a touch panel display and a keyboard for performing an input operation of a command and the like in order for the operator to manage the film forming apparatus 100. A display unit including a display and the like is provided.

  A storage unit 152 is connected to the controller 150. The storage unit 152 is a control program for realizing various processes performed by the film forming apparatus 100 by the control of the controller 150, and for causing each component of the film forming apparatus 100 to perform the process according to the processing conditions. A program or recipe is stored. The recipe is stored, for example, in a storage medium in the storage unit 152. The storage medium may be a hard disk or a semiconductor memory, or may be a portable one such as a CD-ROM, a DVD, a flash memory or the like. Also, the recipe may be properly transmitted from another device, for example, via a dedicated line. The recipe is read from the storage unit 152 according to an instruction from the user interface 151 as necessary, and the controller 150 performs a process according to the read recipe. The desired processing is carried out under the control of 150. In this example, under the control of the controller 150, the method for forming a silicon film described in the first embodiment is performed. In this example, the method of forming a silicon film according to the process (V) is performed.

  When the method of forming a silicon film according to the process (I) is carried out, it is carried out by not using, for example, the halogen-based gas supply source 117c with the configuration of the film forming apparatus 100 shown in FIG. be able to. Of course, it is also possible to omit the halogen-based gas supply source 117 c from the processing gas supply mechanism 114.

  Further, also in the case of carrying out the film forming method of the silicon film according to the process (II), similarly, for example, the hydrocarbon-based gas supply source 117b is not used with the configuration of the film forming apparatus 100 shown in FIG. Alternatively, the process can be implemented by omitting the hydrocarbon-based gas supply source 117 b from the process gas supply mechanism 114.

When the silicon film forming method according to the treatment (III) and the treatment (IV) is carried out, the hydrocarbon-based gas supply source 117 b and the halogen-based gas supply source 117 c of the film forming apparatus 100 shown in FIG. May be replaced with an NH ₃ gas source and an HF gas source, respectively.

  As described above, the method of forming a silicon film according to the first embodiment can be performed by a film forming apparatus 100 as shown in FIG.

  As mentioned above, although this invention was demonstrated according to the 1st, 2nd embodiment, this invention is not limited to the said 1st, 2nd embodiment, It can variously deform in the range which does not deviate from the meaning. is there.

  For example, in the above-mentioned embodiment, although processing conditions were illustrated concretely, processing conditions are not restricted to the above-mentioned concrete illustration.

  In the above embodiment, an example of forming a silicon film by using a vertical batch type film forming apparatus has been described, but it is of course possible to use a single wafer type film forming apparatus, and a batch type other than vertical type It is also possible to use a deposition apparatus.

  In addition, the present invention can be variously modified without departing from the scope of the invention.

DESCRIPTION OF SYMBOLS 1 ... silicon wafer, 2 ... SiO ₂ film, 3 ... silicon film, 4 ... trench, 5 ... SiO ₂ film, 6 ... processed surface with reduced adhesion, 6a ... thin carbon layer, 7 ... amorphous silicon film.

Claims (13)

A silicon film forming method for forming a silicon film on a surface to be processed of an object to be processed, comprising:
(1) performing a process of reducing the adhesion between a silicon film to be formed and the surface to be processed on the surface to be processed of the object to be processed;
(2) supplying a silicon source gas to the surface to be treated to which adhesion with the silicon film to be deposited is reduced, and depositing the silicon film on the surface to be treated;
Equipped with
In the step (1), the surface to be treated is
(II) Process of supplying gas containing halogen-based gas
(III) Process of supplying gas containing NH ₃ gas and HF gas
(IV) NH ₃ after supplying a gas containing a gas and HF gas, film formation characteristics and to Resid silicon film that is one of a step of heat treatment while supplying a gas containing NH ₃ gas Method. The halogen-based gas described in the step (II) is
Fluorine Chlorine Bromine Iodine HCl
HBr
The method for forming a silicon film according to claim 1 , wherein the method is selected from a gas containing at least one of Wherein (1) step Te smell, when selecting the pre Symbol (II) step,
Before performing pre Symbol (II) step, the process of manufacturing a film according to claim 1 or claim 2 wherein the treated surface is characterized by not washing.   A silicon film forming method for forming a silicon film on a surface to be processed of an object to be processed, comprising:
  (1) performing a process of reducing the adhesion between a silicon film to be formed and the surface to be processed on the surface to be processed of the object to be processed;
  (2) supplying a silicon source gas to the surface to be treated to which adhesion with the silicon film to be deposited is reduced, and depositing the silicon film on the surface to be treated;
Equipped with
  In the step (1), the surface to be treated is
    (V) a step of supplying a gas containing a substance to be a raw material of the adhesion lowering layer
And
  The step (V) is a step of forming, on the surface to be treated, an adhesion reduced layer composed of a substance having a cleaving property or a substance having a property of being easily broken physically.
  The gas containing the substance to be the raw material of the adhesion reduced layer described in the step (V) is one obtained by adding a gas containing a halogen-based gas to a hydrocarbon-based gas,
  The method for forming a silicon film, wherein the adhesion reducing layer is a carbon layer. The hydrocarbon-based gas is
C _n H _{2n + 2} (A)
C _m H _{2 m} (B)
C _m H _{2 m-2} (C)
5. The method for forming a silicon film according to claim 4 , wherein the gas is selected from gases containing hydrocarbons represented by at least one of the following formulas.
However, in formulas (A) to (C),
n is a natural number greater than or equal to "1" m is a natural number greater than or equal to "2" The halogen-based gas is
The method for forming a silicon film according to claim 4 or 5 , which is selected from a gas containing at least one of fluorine, chlorine, bromine and iodine. The method for forming a silicon film according to any one of claims 1 to 6 , wherein a concave portion is formed on the surface to be processed. 8. The method for forming a silicon film according to claim 7 , wherein an aspect ratio of the recess is a finite value of “10” or more. Method of forming a silicon film according to claim 7 or claim 8, wherein the minimum line width of the recess is a finite value of "50 nm" or less. The silicon film formed on the surface to be treated is a protective material for filling the recess formed on the surface to be treated and protecting the recess formed on the surface to be treated. The method for forming a silicon film according to any one of claims 7 to 9 . The silicon film according to any one of claims 1 to 10 , wherein the silicon film formed on the processing surface is a film to be removed from the processing surface. Membrane method. The surface to be processed is the process of manufacturing a film according to any one of claims 1 to 11, wherein a silicon oxide is exposed. A film forming apparatus for forming a silicon film on a surface to be processed of a processing object, comprising:
A processing chamber for containing the object to be processed;
A processing gas supply mechanism for supplying a gas used for processing into the processing chamber;
A heating device for heating the object housed in the processing chamber;
Comprising the processing gas supply mechanism and a controller for controlling the heating device;
The controller controls the processing gas supply mechanism and the heating device such that the method for forming a silicon film according to any one of claims 1 to 12 is performed. Membrane device.

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