KR20120129798A - Film formation method and film formation apparatus - Google Patents

Abstract

PURPOSE: An apparatus and a method for forming a film are provided to improve the quality of a thin film by exposing the film to gas activated by plasma generation source. CONSTITUTION: A substrate is put in a vacuum chamber(1). A rotation table(2) is installed in the vacuum chamber. A substrate is mounted in the rotation table. The rotation table rotates. A reaction gas is supplied to the substrate. A reaction gas is adsorbed on the substrate to form a reactant. A gas including hydrogen is supplied to a plasma generation unit to generate plasma. [Reference numerals] (100) Control unit; (101) Memory unit; (102) Media; (AA,BB,CC,DD) N_2 gas

Description

FILM FORMATION METHOD AND FILM FORMATION APPARATUS

This application claims the priority based on Japanese Patent Application No. 2011-111627 filed with the Japan Patent Office on May 18, 2011 and Japanese Patent Application 2011-252832 filed with the Japan Patent Office on November 18, 2011. , Japanese Patent Application No. 2011-111627 and Japanese Patent Application No. 2011-252832 are incorporated herein by reference.

The present invention relates to a film forming method and a film forming apparatus for forming a film on a substrate surface by alternately supplying at least two kinds of reactant gases reacting with each other with respect to the substrate.

In accordance with the further miniaturization of the circuit pattern of the semiconductor device, further thinning and uniformization of various films constituting the semiconductor device are required. As a film forming method in accordance with such a demand, a first reaction gas is supplied to a substrate to adsorb the first reaction gas to the surface of the substrate, and then the second reaction gas is supplied to the substrate to adsorb the first reaction gas to the surface of the substrate. A so-called molecular layer deposition (MLD) method (also referred to as an atomic layer deposition (ALD) method) is known in which a film composed of a reaction product of these reaction gases is deposited on a substrate by reacting a gas with a second reaction gas (example). For example, patent document 1). As a film-forming apparatus which performs the MLD method, what is called a rotating table type | mold is known.

For example, the MLD apparatus proposed by the inventors of the present invention includes a rotary table on which a substrate is loaded, a first reactive gas supply unit for supplying a first reactive gas toward the rotary table, and a second reactive gas toward the rotary table. It has a 2nd reaction gas supply part which supplies a, and a separation area provided between a 1st reaction gas supply part and a 2nd reaction gas supply part, and isolate | separates a 1st reaction gas and a 2nd reaction gas. The separation region is provided with a ceiling surface lower than the region supplied with the first reaction gas and the region supplied with the second reaction gas, and the separation gas supply unit for supplying the separation gas (Patent Document 2).

In such an MLD apparatus, by rotating the rotary table, the first reaction gas is adsorbed to the substrate surface on the rotary table, and the first reaction gas adsorbed on the substrate surface reacts with the second reaction gas, whereby the reaction product appears on the substrate surface. A film of reaction product is deposited on the substrate surface. In particular, since the first reaction gas and the second reaction gas can be sufficiently separated by the separation region, throughput can be improved by relatively increasing the rotation speed of the rotary table.

However, in the prior art, it was difficult to deposit a thin film having excellent film thickness distribution and film quality while maintaining the film formation rate.

Japanese Patent Laid-Open No. 2001-254181 Japanese Patent No. 4661990

The present invention provides a film forming method and a film forming apparatus which can deposit a thin film having excellent film thickness distribution and film quality while maintaining the film forming speed.

According to the first aspect of the present invention, a step of loading a substrate into a vacuum container, loading the substrate on a rotary table provided to be rotatable in the vacuum container, rotating the rotary table, and a first reactive gas supply unit An adsorption step of supplying a first reaction gas to the substrate from the substrate and adsorbing the first reaction gas to the substrate, and a second reaction reacting with the first reaction gas to the substrate from a second reaction gas supply unit A forming step of supplying a gas and reacting the first reaction gas adsorbed to the substrate with the second reaction gas to form a reaction product on the substrate; and the rotation from the first and second reaction gas supply units. Hydrogen-containing gas is supplied to the plasma generating unit spaced apart in the circumferential direction of the table, and above the rotary table. There is provided a film forming method comprising the step of generating a plasma.

According to the second aspect of the present invention, there is provided a substrate loading portion on which a substrate is loaded, and a first reaction gas is supplied to a rotary table provided to be rotatable in a vacuum container, and the substrate loaded on the substrate loading portion, A first reactive gas supply unit for adsorbing the first reactive gas to the substrate and spaced apart from the first reactive gas supply unit in the circumferential direction of the turntable to supply a second reactive gas to the substrate; A second reaction gas supply unit for reacting the first reaction gas adsorbed on the substrate with the second reaction gas to form a reaction product on the substrate, and the circumferential direction of the rotary table from the first and second reaction gas supply units A plasma generator that is spaced apart from each other and generates plasma above the rotary table, and the plasma generator The film forming apparatus having a gas supply pipe for supplying a gas containing hydrogen is provided for.

Other features of the present invention will become apparent by reading the following detailed description with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic sectional drawing which shows the film-forming apparatus by embodiment of this invention.
FIG. 2 is a schematic perspective view illustrating a configuration in a vacuum container of the film forming apparatus of FIG. 1. FIG.
FIG. 3 is a schematic plan view showing a configuration in a vacuum container of the film forming apparatus of FIG. 1. FIG.
4 is a schematic cross-sectional view of the vacuum container along a concentric circle of a rotary table provided to be rotatable in the vacuum container of the film forming apparatus of FIG. 1.
5 is another schematic cross-sectional view of the film forming apparatus of FIG. 1.
6 is a schematic cross-sectional view showing a plasma generation source provided in the film forming apparatus of FIG. 1.
FIG. 7A is another schematic cross-sectional view illustrating a plasma generation source provided in the film forming apparatus of FIG. 1. FIG.
7B is a schematic top view of a plasma generation source provided in the film forming apparatus of FIG. 1.
8A is a graph showing experimental results of an experiment conducted to investigate the effect of the film forming method according to the embodiment of the present invention, and a graph showing the NH ₃ gas flow rate dependency of the film forming rate.
8B is a graph showing experimental results of an experiment conducted to investigate the effect of the film forming method according to the embodiment of the present invention, and a graph showing NH ₃ gas flow rate dependency of film thickness uniformity.
9 is another graph showing experimental results of an experiment conducted to investigate the effect of the film forming method according to the embodiment of the present invention.
10 is another graph showing experimental results of an experiment conducted to investigate the effect of the film forming method according to the embodiment of the present invention.
11A and 11B are explanatory diagrams explaining the effects of the film forming method according to the embodiment of the present invention.
The graph which shows the result of the experiment performed in order to confirm the effect of the film-forming method by the modified example of embodiment of this invention.
FIG. 13 is a graph showing the results of another experiment conducted to confirm the effect of the film forming method according to the modification of the embodiment of the present invention. FIG.

The following knowledge was obtained as a result of examination to further improve the throughput in the rotary table type film forming apparatus described as the related art. The faster the rotation speed of the turntable, the first reactant gas is adsorbed onto the substrate surface before the first reactant gas and the second reactant gas adsorbed on the substrate surface sufficiently react, and the reactant product in which the reaction by-product is produced. It may remain in the inside or the density of a reaction product may fall, and it may become difficult to improve throughput while obtaining a high quality thin film.

For this reason, it has been attempted to modify the thin film by providing a plasma generation source so as to face the turntable, and exposing the thin film generated on the surface of the substrate to the gas activated by the plasma generation source. As a result, although the improvement of film quality was recognized, the phenomenon that the film-forming speed | rate and film thickness distribution deteriorated came to be recognized.

DESCRIPTION OF THE EMBODIMENTS Hereinafter, non-limiting illustrated embodiments of the present invention will be described with reference to the accompanying drawings. This embodiment is made based on the above knowledge, and is a technique capable of depositing a thin film having excellent film thickness distribution and film quality while maintaining the film formation rate. In the accompanying drawings, the same or corresponding members or parts are given the same or corresponding reference numerals, and redundant descriptions are omitted. Further, the drawings are not intended to show the relative ratio between members or parts, and therefore, specific dimensions should be determined by those skilled in the art in light of the following non-limiting embodiments.

1 to 3, a film forming apparatus according to an embodiment of the present invention is provided with a flat vacuum container 1 having a substantially circular planar shape, provided in the vacuum container 1, and a vacuum container 1. The turntable 2 which has a rotation center in the center of the is provided. The vacuum container 1 has a bottomed cylindrical container body 12 and a top surface of the container body 12 via, for example, a seal member 13 (FIG. 1) such as an O-ring. It has the ceiling plate 11 arrange | positioned so that a gas is detachably attached.

The turntable 2 is fixed to the cylindrical core portion 21 at the center, and the core portion 21 is fixed to the upper end portion of the rotation shaft 22 extending in the vertical direction. The rotating shaft 22 penetrates the bottom part 14 of the vacuum container 1, and the lower end part is provided in the drive part 23 which rotates the rotating shaft 22 (FIG. 1) about a vertical axis. The rotating shaft 22 and the drive part 23 are accommodated in the cylindrical case body 20 with an upper surface opened. In the case body 20, the flange portion provided on the upper surface thereof is airtightly installed on the bottom surface of the bottom portion 14 of the vacuum container 1, and the airtight state of the inner body and the external atmosphere of the case body 20 is Maintained.

As shown in FIGS. 2 and 3, a surface of the turntable 2 is a semiconductor wafer (hereinafter referred to as a “wafer”) that is a plurality of substrates (five in the illustrated example) along the rotation direction (peripheral direction). The circular recessed part 24 for loading W is provided. 3, the wafer W is shown only by the one recessed part 24 for convenience. This recessed part 24 has an inner diameter which is only 4 mm larger than the diameter of the wafer W, for example, and a depth substantially equal to the thickness of the wafer W. FIG. Therefore, when the wafer W is accommodated in the recessed part 24, the surface of the wafer W and the surface of the rotating table 2 (region where the wafer W is not mounted) become the same height. The bottom surface of the recessed part 24 is provided with the through-hole (not shown) which the three lifting pins pass through, for example, for lifting up the wafer W by supporting the back surface of the wafer W. As shown in FIG.

2 and 3 are views for explaining the structure in the vacuum chamber 1, and the top plate 11 is omitted for convenience of explanation. As shown in FIG. 2 and FIG. 3, the reaction gas nozzle 31, the reaction gas nozzle 32, and the separation gas nozzles 41 and 42 each containing quartz, for example, above the turntable 2. And the gas introduction nozzles 92 are spaced apart from each other in the circumferential direction of the vacuum container 1 (the rotation direction of the turntable 2 (arrow A in FIG. 3)). In the example shown in figure, the gas introduction nozzle 92, the separation gas nozzle 41, the reaction gas nozzle 31, and the separation gas nozzle are carried out clockwise (rotational direction of the turntable 2) from the conveyance port 15 mentioned later. 42 and the reaction gas nozzle 32 are arranged in this order. These nozzles 92, 31, 32, 41, and 42 are gas introduction ports 92a, 31a, 32a, 41a, and 42a which are proximal ends of the nozzles 92, 31, 32, 41, and 42 (FIG. 3). Is fixed to the outer circumferential wall of the container body 12 to be introduced into the vacuum container 1 from the outer circumferential wall of the vacuum container 1, and horizontally with respect to the turntable 2 along the radial direction of the container body 12. It is installed to extend.

Moreover, the plasma generation source 80 is provided above the gas introduction nozzle 92 so that it may be simplified and shown with a broken line in FIG. The plasma generation source 80 will be described later.

The reaction gas nozzle 31 is connected to a supply source (not shown) of Si (silicon) -containing gas as the first reaction gas through a pipe (not shown), a flow regulator, and the like. The reaction gas nozzle 32 is connected to the supply source (not shown) of the oxidizing gas as a 2nd reaction gas through piping, a flow regulator, etc. which are not shown in figure. The separation gas nozzles 41 and 42 are both connected to a supply source (not shown) of nitrogen (N ₂ ) gas as the separation gas through a pipe (not shown), a flow control valve, and the like.

Si-containing gas, for example, may be used an organic aminosilane gas, oxidation gas, for example O ₃ (ozone) may be a gas or O ₂ (oxygen) gas or a mixed gas.

In the reaction gas nozzles 31 and 32, a plurality of gas discharge holes 33 opening toward the rotary table 2 are arranged along the longitudinal direction of the reaction gas nozzles 31 and 32, for example, at intervals of 10 mm. It is. The area | region below the reaction gas nozzle 31 becomes 1st process area | region P1 for making Si containing gas adsorb | suck to the wafer W. As shown in FIG. The lower region of the reaction gas nozzle 32 becomes the second processing region P2 for oxidizing the Si-containing gas adsorbed to the wafer W in the first processing region P1.

2 and 3, two convex portions 4 are provided in the vacuum chamber 1. The convex part 4 is provided in the back surface of the ceiling plate 11 so that it may protrude toward the rotating table 2 so that the convex part 4 may comprise the separation area D with the separation gas nozzle 41 and 42. . Further, the convex portion 4 has a fan-shaped planar shape in which the top portion is cut into an arc shape. In this embodiment, the inner circular arc is connected to the protrusion 5 (described later), and the outer circular arc is a vacuum container ( It is arrange | positioned so that the inner peripheral surface of the container main body 12 of 1) may be followed.

4 shows a cross section of the vacuum container 1 along the concentric circles of the turntable 2 from the reaction gas nozzle 31 to the reaction gas nozzle 32. As shown, since the convex part 4 is provided in the back surface of the ceiling plate 11, in the vacuum container 1, the flat low ceiling surface 44 which is the lower surface of the convex part 4 (first 1 ceiling surface and the ceiling surface 45 (2nd ceiling surface) higher than the ceiling surface 44 located in the circumferential direction both sides of this ceiling surface 44 exists. The ceiling surface 44 has a fan-shaped plane shape in which the top portion is cut into an arc shape. In addition, as shown, the convex part 4 is formed with the groove part 43 formed so that radially extended in the circumferential direction center, and the separation gas nozzle 42 is accommodated in the groove part 43. As shown in FIG. The groove 43 is similarly formed in the other convex part 4, and the separation gas nozzle 41 is accommodated here. In addition, the reaction gas nozzles 31 and 32 are provided in the space below the high ceiling surface 45, respectively. These reaction gas nozzles 31 and 32 are provided in the vicinity of the wafer W, spaced apart from the ceiling surface 45. For convenience of explanation, as shown in FIG. 4, a space below the high ceiling surface 45 on which the reaction gas nozzle 31 is provided is indicated by reference numeral 481, and the reaction gas nozzle 32 is The space below the high ceiling surface 45 to be installed is indicated by reference numeral 482.

Further, a plurality of gas discharge holes 41h (see FIG. 4) opening toward the rotary table 2 are separated from the separation gas nozzles 41 and 42 accommodated in the groove portion 43 of the convex portion 4. Along the longitudinal direction of the gas nozzles 41 and 42, for example, they are arranged at intervals of 10 mm.

The ceiling surface 44 forms the separation space H which is a narrow space with respect to the turntable 2. When the N ₂ gas is supplied from the discharge hole 42h of the separation gas nozzle 42, the N ₂ gas flows through the separation space H toward the space 481 and the space 482. At this time, since the volume of the separation space H is smaller than the volumes of the spaces 481 and 482, the pressure of the separation space H can be made higher than that of the spaces 481 and 482 by the N ₂ gas. That is, a separation space H having a high pressure is formed between the spaces 481 and 482. In addition, the N ₂ gas flowing from the separation space H into the spaces 481 and 482 serves as a counter flow for the Si-containing gas from the first region P1 and the oxidizing gas from the second region P2. Therefore, the Si-containing gas from the first region P1 and the oxidizing gas from the second region P2 are separated by the separation space H. Accordingly, the Si-containing gas and the oxidizing gas are mixed and reacted in the vacuum chamber 1.

Further, the rotary table (2) the top face 44, the height h1 is, the film formation when the pressure in the vacuum chamber (1), the rotary table (2) rotational speed, the separation gas supplying (N ₂ gas) for the upper surface of the In consideration of the supply amount and the like, it is preferable to set the pressure of the separation space H to a height suitable for increasing the pressure of the spaces 481 and 482.

On the other hand, the lower surface of the ceiling plate 11 is provided with the protrusion part 5 (FIG. 2 and FIG. 3) surrounding the outer periphery of the core part 21 which fixes the turntable 2. As shown in FIG. This protrusion part 5 is continuous with the site | part on the rotation center side in the convex part 4 in this embodiment, and the lower surface is formed in the same height as the ceiling surface 44. As shown in FIG.

FIG. 1 mentioned above is sectional drawing along the II 'line of FIG. 3, and has shown the area | region in which the ceiling surface 45 is provided. 5 is sectional drawing which shows the area | region in which the ceiling surface 44 is provided. As shown in FIG. 5, the periphery of the fan-shaped convex part 4 (part on the outer edge side of the vacuum container 1) is bent in an L shape so as to face the outer end surface of the turntable 2. The curved portion 46 is formed. Similar to the convex portion 4, the bent portion 46 suppresses intrusion of reaction gas from both sides of the separation region D and suppresses mixing of both reaction gases. Since the fan-shaped convex part 4 is provided in the ceiling plate 11, and the ceiling plate 11 is peeled off from the container main body 12, it is slightly between the outer peripheral surface of the curved part 46 and the container main body 12. There is a gap. The gap between the inner circumferential surface of the bent portion 46 and the outer end surface of the turntable 2 and the gap between the outer circumferential surface of the bent portion 46 and the container body 12 are, for example, a ceiling surface with respect to the upper surface of the turntable 2. It is set to the same dimension as the height of (44).

The inner circumferential wall of the container main body 12 is formed in a vertical plane near the outer circumferential surface of the bent portion 46 as shown in FIG. 4 in the separation region D, but is shown in FIG. As mentioned above, for example, it recesses outward over the bottom part 14 from the site | part which opposes the outer end surface of the turntable 2. Hereinafter, for convenience of explanation, the concave portion having a generally rectangular cross-sectional shape is referred to as an exhaust region. Specifically, the exhaust region communicating with the first processing region P1 is referred to as the first exhaust region E1, and the region communicating with the second processing region P2 is referred to as the second exhaust region E2. In the bottom part of these 1st exhaust area | region E1 and the 2nd exhaust area | region E2, as shown in FIGS. 1-3, the 1st exhaust port 610 and the 2nd exhaust port 620 are formed, respectively. As illustrated in FIG. 1, the first exhaust port 610 and the second exhaust port 620 are connected to, for example, a vacuum pump 640 as a vacuum exhaust means through an exhaust pipe 630. 1, reference numeral 650 denotes a pressure regulator.

In the space between the rotary table 2 and the bottom portion 14 of the vacuum container 1, as shown in Figs. 1 and 4, a heater unit 7 as a heating means is provided, and the rotary table 2 is mounted. The wafer W on the turntable 2 is heated to a temperature (for example, 450 ° C.) determined by the process recipe. At the lower side of the rotary table 2 near the periphery, the atmosphere from the upper space of the rotary table 2 to the exhaust regions E1 and E2 and the atmosphere in which the heater unit 7 is placed are divided into the rotary table 2. In order to suppress the invasion of the gas to a downward region, the ring-shaped cover member 71 is provided (FIG. 5). The cover member 71 is provided with an inner member 71a provided so as to face the outer circumferential side from the lower side than the outer edge portion and the outer edge portion of the turntable 2, and the inner member 71a and the vacuum container 1. The outer member 7lb provided between the inner wall surfaces of is provided. The outer member 7lb is provided near the bent portion 46 below the bent portion 46 formed in the outer edge portion of the convex portion 4 in the separation region D, and the inner member 71a is a turntable. The heater unit 7 is enclosed over the entire circumference below the outer edge portion (and slightly below the outer edge portion of the outer edge portion) in (2).

The bottom portion 14 at the portion closer to the rotation center than the space where the heater unit 7 is disposed is located upwards so as to approach the core portion 21 near the center of the lower surface of the turntable 2. It protrudes and forms the protrusion part 12a. The space between the protruding portion 12a and the core portion 21 is a narrow space, and the gap between the inner circumferential surface of the through hole of the rotating shaft 22 passing through the bottom portion 14 and the rotating shaft 22 is narrowed. These narrow spaces communicate with the case body 20. The case body 20 is provided with a purge gas supply pipe 72 for supplying and purging N ₂ gas, which is a purge gas, in a narrow space. Moreover, the bottom part 14 of the vacuum container 1 has several purge gas supply pipes which purge the arrangement space of the heater unit 7 at predetermined angle intervals in the circumferential direction below the heater unit 7 ( 73) (one purge gas supply pipe 73 is shown in FIG. 5). Moreover, between the heater unit 7 and the turntable 2, in order to suppress the invasion of the gas to the area | region in which the heater unit 7 was installed, the inner peripheral wall (upper surface of the inner member 71a) of the outer member 7lb. ) Is provided with a lid member 7a that covers the upper end of the protruding portion 12a over the circumferential direction. The lid member 7a can be made of, for example, quartz.

In addition, a separation gas supply pipe 51 is connected to a central portion of the top plate 11 of the vacuum vessel 1 so that the N ₂ gas serving as the separation gas is supplied to the space 52 between the top plate 11 and the core portion 21. It is configured to supply. Separation gas supplied to this space 52 is discharged toward the periphery along the surface of the wafer loading area side of the turntable 2 via the narrow gap 50 between the protrusion part 5 and the turntable 2. do. The space 50 can be maintained at a higher pressure than the space 481 and the space 482 by the separation gas. Therefore, the space 50 suppresses mixing of the Si-containing gas supplied to the first processing region P1 and the oxidizing gas supplied to the second processing region P2 through the central region C. FIG. That is, the space 50 (or the central region C) can function similarly to the separation space H (or the separation region D).

Moreover, as shown in FIG.2, FIG.3, the sidewall of the vacuum container 1 is a conveyance port for exchanging the wafer W which is a board | substrate between the external conveyance arm 10 and the turntable 2. As shown in FIG. (15) is formed. This conveyance port 15 is opened and closed by a gate valve (not shown). Moreover, since the recessed part 24 which is a wafer loading area in the turntable 2 exchanges the wafer W between the conveyance arms 10 in the position which faces this conveyance port 15, the turntable ( 2) a lifting pin and a lifting mechanism (not shown) for passing through the concave portion 24 to lift the wafer W from the back side and a lifting mechanism thereof (both not shown) are provided at a portion corresponding to the transfer position at the lower side of 2). have.

Next, the plasma generation source 80 will be described with reference to FIGS. 6 to 7B. FIG. 6 is a schematic cross-sectional view of the plasma generation source 80 along the radial direction of the turntable 2, and FIG. 7A is a schematic cross-sectional view of the plasma generation source 80 along a direction orthogonal to the radial direction of the turntable 2. 7B is a top view illustrating the outline of the plasma generation source 80. For convenience of illustration, some of the members are simplified in these drawings.

Referring to FIG. 6, the plasma generating source 80 is made of a high-frequency transmissive material, has a concave portion concave from an upper surface, and is fitted with a frame member 81 fitted into an opening 11 a formed in the top plate 11, The Faraday shielding plate 82 which is accommodated in the recessed part of the frame member 81, and has the substantially box-shaped shape which the upper part opened, the insulating plate 83 arrange | positioned on the bottom face of the Faraday shielding plate 82, and the insulating plate ( It is supported above 83, and has a coil-shaped antenna 85 having an approximately octagonal top surface shape.

The opening 11a of the top plate 11 has a plurality of stepped portions, one of which is formed with a groove portion over its entire circumference, and a seal member 81a such as an O-ring, for example, is formed in the groove portion. It is sandwiched. On the other hand, the frame member 81 has a plurality of stepped portions corresponding to the stepped portion of the opening 11a. When the frame member 81 is inserted into the opening 11a, the back surface of one of the plurality of stepped portions is formed. This is in contact with the sealing member 81a sandwiched in the groove portion of the opening 11a, whereby the airtightness between the ceiling plate 11 and the frame member 81 is maintained. 6, the pressing member 81c along the outer periphery of the frame member 81 inserted in the opening 11a of the ceiling plate 11 is provided, and the frame member 81 is a ceiling plate by this. It is pressed downward against (11). For this reason, the airtightness between the ceiling plate 11 and the frame member 81 is maintained more reliably.

The lower surface of the frame member 81 faces the rotary table 2 in the vacuum container 1, and the protrusion 81b protrudes downward (toward the rotary table 2) over its entire circumference on the outer periphery of the lower surface thereof. ) Is installed. The lower surface of the projection part 81b is close to the surface of the turntable 2, and the upper part of the turntable 2 is provided by the projection part 81b, the surface of the turntable 2, and the lower surface of the frame member 81. As shown in FIG. The space (hereinafter, referred to as the internal space S) is configured. In addition, the space | interval of the lower surface of the projection part 81b and the surface of the rotating table 2 is substantially equal to the height h1 with respect to the upper surface of the rotating table 2 of the ceiling surface 11 in separation space H (FIG. 4). It may be the same.

Moreover, the gas introduction nozzle 92 which penetrated the projection 81b is extended in this internal space S. As shown in FIG. In the present embodiment, as illustrated in FIG. 6, the gas introduction nozzle 92 is an argon gas supply source 93a filled with argon (Ar) gas and an oxygen gas supply source filled with oxygen (O ₂ ) gas. there are (93b) and ammonia (NH ₃₎ ammonia gas source (93c) where the gas is charged is connected. From the argon gas supply source 93a, the oxygen gas supply source 93b, and the ammonia gas supply source 93c, Ar gas, O ₂ gas, and NH ₃ gas controlled by the corresponding flow controllers 94a, 94b, and 94c are predetermined. The flow rate ratio (mixing ratio) is supplied to the internal space S.

In addition, a plurality of discharge holes 92h are formed in the gas introduction nozzle 92 at predetermined intervals (for example, 10 mm) along the longitudinal direction thereof, and the above-described Ar gas is discharged from the discharge holes 92. do. As shown in FIG. 7A, the discharge hole 92h is inclined from the direction perpendicular to the turntable 2 toward the upstream side of the turn direction of the turntable 2. For this reason, the gas supplied from the gas introduction nozzle 92 is a direction opposite to the rotation direction of the turntable 2, specifically, toward the clearance gap between the lower surface of the projection 81b and the surface of the turntable 2. Discharged. This suppresses the inflow of the reaction gas or the separation gas into the internal space S from the space below the ceiling surface 45 located upstream from the plasma generation source 80 along the rotation direction of the turntable 2. . In addition, as described above, since the projection 81b formed along the outer periphery of the lower surface of the frame member 81 is close to the surface of the turntable 2, the interior of the gas introduction nozzle 92 is opened by the gas from the gas introduction nozzle 92. The pressure in the space S can be easily maintained high. This also suppresses the inflow of the reaction gas and the separation gas into the internal space S.

The Faraday shield plate 82 is made of a conductive material such as metal, and is omitted although not shown. As clearly shown in FIG. 7B, a plurality of slits 82s are formed at the bottom of the Faraday shielding plate 82. Each slit 82s extends substantially perpendicular to the corresponding side of the antenna 85 having an approximately octagonal planar shape.

In addition, the Faraday shielding plate 82 has a supporting portion 82a that is bent outward at two positions at the upper end as shown in FIGS. 7A and 7B. By supporting the support portion 82a on the upper surface of the frame member 81, the Faraday shielding plate 82 is supported at a predetermined position in the frame member 81.

The insulating plate 83 is made of, for example, quartz glass, has a size slightly smaller than that of the Faraday shielding plate 82, and is mounted on the bottom of the Faraday shielding plate 82. The insulating plate 83 insulates the Faraday shield plate 82 from the antenna 85, while transmitting the high frequency radiated from the antenna 85 downward.

The antenna 85 is formed by winding a copper hollow tube (pipe) in three layers, for example, so that a planar shape may become substantially octagonal. Cooling water can be circulated in the pipe, thereby preventing the antenna 85 from being heated to high temperature by the high frequency supplied to the antenna 85. Moreover, the vertical mounting part 85a is provided in the both ends of the antenna 83, and the support part 85b is provided in the vertical mounting part 85a. By the support portion 85b, the antenna 85 is held at a predetermined position in the Faraday shield plate 82. In addition, a high frequency power source 87 is connected to the support portion 85b via a matching box 86. The high frequency power supply 87 may generate a high frequency having a frequency of 13.56 MHz, for example.

According to the plasma generation source 80 having such a configuration, when the high frequency power is supplied from the high frequency power source 87 to the antenna 85 via the matching box 86, the electronic machine generates the antenna 85. Since the electric field component of this electromagnetic field is shielded by the Faraday shielding plate 82, it cannot propagate downward. On the other hand, the magnetic field component propagates in the internal space S through the plurality of slits 82s of the Faraday shielding plate 82. By this magnetic field component, plasma is generated from gases such as Ar gas, O ₂ gas and NH ₃ gas supplied from the gas introduction nozzle 92 to the internal space S at a predetermined flow rate ratio (mixing ratio). According to the plasma generated in this way, the damage to irradiation of the thin film deposited on the wafer W, the damage of each member in the vacuum container 1, etc. can be reduced.

In addition, as shown in FIG. 1, the film-forming apparatus by this embodiment is provided with the control part 100 which consists of a computer for controlling the operation | movement of the whole apparatus, and in the memory of this control part 100 is carried out. Under the control of the controller 100, a program for causing the film forming apparatus to perform the film forming method described later is stored. The program is organized in a step group so as to execute the film forming method described below, and is stored in a medium 102 such as a hard disk, a compact disk, a magneto-optical disk, a memory card, a flexible disk, and the like by a predetermined reading device. It is read by 101 and installed in the control part 100.

Next, the film forming method according to the embodiment of the present invention will be described taking the case of using the film forming apparatus 1 described above as an example. For this reason, the drawings referred to so far are appropriately referred to.

First, the gate valve which is not shown in figure is opened, and the wafer W is sent in the recessed part 24 of the turntable 2 via the conveyance port 15 (FIG. 3) by the conveyance arm 10 from the exterior. This transfer is carried out by the bottom of the vacuum container 1, not shown, through the through-hole of the bottom face of the recessed part 24 when the recessed part 24 stopped at the position which faces the conveyance opening 15. FIG. This is done by raising and lowering the pin. Such a transfer of the wafers W is performed by rotating the rotary table 2 intermittently, and the wafers W are respectively loaded in the five recesses 24 of the rotary table 2.

Subsequently, the gate valve is closed, and the vacuum container 1 is evacuated to the lowest achieved vacuum degree by the vacuum pump 640, and then the N ₂ gas serving as the separation gas is discharged from the separation gas nozzles 41 and 42 at a predetermined flow rate. The N ₂ gas is also discharged from the separation gas supply pipe 51 and the purge gas supply pipes 72 and 72 at a predetermined flow rate. Thereby, the pressure regulator 650 adjusts the inside of the vacuum container 1 to the preset process pressure. Subsequently, the wafer W is heated to, for example, 450 ° C. by the heater unit 7 while rotating the rotary table 2 in a clockwise direction, for example, at a rotational speed of up to 240 rpm.

Thereafter, the Si-containing gas and the O ₃ gas are discharged from the reaction gas nozzles 31 and 32, respectively. In addition, a mixed gas of Ar gas, O ₂ gas and NH ₃ gas mixed at a predetermined flow rate ratio is supplied from the gas introduction nozzle 92 to the internal space S, and the antenna of the plasma generation source 80 is supplied from the high frequency power source 87. The high frequency is supplied to the 85 at a power of, for example, 700W. As a result, plasma is generated in the internal space S. FIG. In this plasma, not only active oxygen species such as oxygen ions and oxygen radicals, but also active hydrogen species such as hydrogen ions and hydrogen radicals generated by decomposition of NH ₃ by the plasma are also present.

Here, silicon oxide is formed in the wafer W as follows while the turntable 2 rotates one time. That is, when the wafer W first passes the first processing region P1 below the reaction gas nozzle 31, the Si-containing gas is adsorbed onto the surface of the wafer W. Subsequently, when the wafer W passes through the second processing region P2 below the reaction gas nozzle 32, the Si-containing gas on the wafer W is oxidized by the O ₃ gas from the reaction gas nozzle 32 to oxidize it. One molecular layer (or water molecule layer) of silicon is formed. Subsequently, when the wafer W passes below the plasma generation source 80, the silicon oxide layer on the wafer W is exposed to active oxygen species and active hydrogen species. Active oxygen species, such as an oxygen radical, act to deviate from a silicon oxide layer, for example by oxidizing the organic substance contained in Si containing gas and remaining in the silicon oxide layer. As a result, the silicon oxide layer can be highly purified. In addition, when high energy of active oxygen species such as oxygen radicals is transferred to Si atoms or oxygen atoms in the silicon oxide layer, the Si atoms and oxygen atoms vibrate in the silicon oxide layer, and they may be rearranged. Through such high purity and rearrangement, the silicon oxide layer is modified to obtain a high quality silicon oxide layer. In addition, the effect considered to be exhibited by active hydrogen species is mentioned later with an experiment result.

Or less, the supply of and after the rotation the desired film by the rotary table the number of times that a silicon oxide film formed has a thickness (2), Si-containing gas and, O ₃ gas, and, Ar gas, O ₂ gas and NH ₃ gas mixture gas of The film formation method is terminated by stopping. Subsequently, the supply of the N ₂ gas from the separation gas nozzles 41 and 42, the separation gas supply pipe 51, and the purge gas supply pipes 72 and 72 is also stopped, and the rotation of the turntable 2 is stopped. Thereafter, the wafer W is taken out from the vacuum container 1 by the procedure opposite to that when the wafer W is loaded into the vacuum container 1.

Next, the experimental result of the experiment performed in order to confirm the effect of the film-forming method which concerns on this embodiment is demonstrated. The experiment was performed using the wafer W of 300 mm diameter and following the procedure of the film-forming method mentioned above on condition of the following.

Rotational speed of the turntable 2: 20 rpm

Pressure in vacuum vessel 1: 133 Pa (1 Torr)

Flow rate of Si-containing gas from the reaction gas nozzle 31: 100 sccm

Flow rate of the O ₃ gas from the reaction gas nozzle 32: 10000 sccm

Flow rate of Ar gas supplied to the gas introduction nozzle 92: 10000 sccm

Flow rate of the O ₂ gas supplied to the gas introduction nozzle 92: 50 sccm

Flow rate of NH ₃ gas supplied to the gas introduction nozzle 92: 0 to 150 sccm

High frequency power supplied to the plasma generator 80: 1400 W (frequency 13.56 MHz)

In the experiment, film forming is performed for several times I by changing the flow rate of the NH ₃ gas, a silicon oxide film deposited on the wafer W various properties was examined how the change by the flow rate of NH ₃ gas.

8A is a graph showing the NH ₃ gas flow rate dependency of the deposition rate. The deposition rate was determined by obtaining the average film thickness of the silicon oxide film measured at 49 points in the plane of each wafer W and dividing the average film thickness by the film formation time. As shown, it can be seen that the deposition rate becomes substantially constant, and in the increase with the increase in the flow rate of NH ₃ gas, NH ₃ gas flow rate of 15sccm over, more preferably not less than 30sccm. The reason why the film formation rate is increased by supply of the NH ₃ gas will be described later in accordance with the following experimental results.

8B is a graph showing NH ₃ gas flow rate dependency of film thickness uniformity. Film thickness uniformity was calculated | required by (maximum film thickness-minimum film thickness) / (average film thickness) about the film thickness of the silicon oxide film measured at 49 points in-plane of each wafer W. As shown in FIG. , And the film thickness uniformity as shown castle improved by accompanying the increase in the NH ₃ gas flow rate, it seems a tendency of deteriorating If further increasing the NH ₃ gas flow rate. In the range from 15 sccm to 75 sccm of NH ₃ gas flow rate, the film thickness uniformity is included in the range from 1.67% to 2.88%, and it can be said that sufficient uniformity is obtained. In addition, when the NH ₃ gas flow rate was in the range of 25 sccm to 50 sccm, the film thickness uniformity was included from 1.67% to 1.82%, and it can be said that a silicon oxide film having excellent uniformity was obtained. In addition, the flow rate of the Ar gas supplied to the gas inlet nozzle (92) 10000sccm with NH ₃ gas, NH ₃ to the flow rate It is preferable when the gas flow rate is in the range of 0.15% to 0.75%, and more preferably in the range of 0.3% to 0.5%.

9 is a graph showing the results of a breakdown voltage test of a silicon oxide film formed by supplying 30 sccm of a NH ₃ gas flow rate. The measurement was performed at nine points in the plane of the wafer W (see the insertion drawing in the graph of FIG. 9). The current density-electric field curve is almost superimposed at nine measurement points, and from this result, it can be said that the breakdown voltage characteristic of the silicon oxide film is almost uniform in the wafer W plane.

10 is a transform infrared spectroscopy (FTIR) Fourier the density of Si-OH bond and an OH group included the NH ₃ gas to a film forming the silicon oxide film and the NH ₃ gas, without supplying to 30sccm supplied to a film forming the silicon oxide film The result of the measurement is shown. If the supply of NH ₃ gas in comparison with the case that does not supply, NH ₃ gas as shown, it is possible the Si-OH bond OH groups than seen that increased relatively. From this result, it is suggested that the plasma generated in the internal space S by the plasma generation source 80 decomposes NH ₃ gas to generate active hydrogen species such as H radicals and bonds with oxygen atoms on the wafer W surface. The OH group of the Si-OH bond thus produced can be considered to act as an adsorption site for Si-containing gas. As shown in Fig. 11A, when an oxygen atom surface appears on the outermost surface of the silicon oxide film during film formation, the Si-containing gas is difficult to adsorb to the outermost surface thereof, or is adsorbed before being oxidized by O ₃ gas even if adsorbed on the outermost surface thereof. Throw it away. However, as shown in Fig. 11B, when an oxygen atom is terminated with a hydrogen atom by an active hydrogen species derived from NH ₃ gas, the Si-containing gas is easily caused by, for example, an intermolecular force acting between its OH groups. It is thought to be adsorbed. Therefore, the adsorption of the Si-containing gas is promoted, and as a result, the deposition rate of the silicon oxide film is considered to be increased as compared with the case of not supplying the NH ₃ gas.

In addition, the Si-OH bond formed by the active hydrogen species generated by decomposition of the NH ₃ gas is uniformly distributed on the outermost surface of the silicon oxide film, and the Si-containing gas is adsorbed thereon, thereby oxidizing the ozone gas. It is considered that the film thickness uniformity of the formed silicon oxide film is further improved. The improvement in film thickness uniformity as shown in FIG. 8B can be considered to be for this reason.

Further, in the results of measurement of the etching rate carried out by the inventors of the present invention, also it did not show a significant increase in the etching rate when the supply of NH ₃ gas. For this reason, it is thought that the hydrogen atom of the OH group in a Si-OH bond will leave with reaction product at the time of oxidation of Si containing gas, and will not remain to such an extent that it affects an etching characteristic. Furthermore, secondary ion mass spectrometry (SIMS) the result of the measurement, if even if the supplying NH ₃ gas in the inner space S, the nitrogen increases in the silicon oxide film obtained using there was little. That is, the adverse effect of the supply of the NH ₃ gas may substantially not.

Next, the modified example of embodiment mentioned above is demonstrated. In this modification, the Si-containing gas is adsorbed on the surface of the wafer W (hereinafter simply referred to as adsorption) by supplying the Si-containing gas from the reaction gas nozzle 31 while rotating the rotary table 2 to react. By supplying ozone gas from the gas nozzle 32, the adsorbed Si-containing gas is oxidized to produce silicon oxide (hereinafter simply referred to as oxidation), and the plasma generating source 80 contains a hydrogen-containing gas. Prior to the cycle of irradiating the silicon oxide with plasma generated gas (mixed gas of Ar, O ₂ and NH ₃ ) to silicon oxide (hereinafter simply referred to as plasma irradiation), the silicon oxide film is formed by adsorption and oxidation. The reason for this film formation is as follows.

In the initial stage of forming the silicon oxide film, the plasma may pass through the silicon oxide film and reach the underlying silicon layer (or wafer). In this case, since the silicon layer is oxidized and becomes a silicon oxide layer (plasma silicon oxide layer) at the portion where the plasma reaches, the thickness of the silicon layer becomes thin. For example, if there is a conductive polysilicon wiring layer as a base on which a silicon oxide film is formed, the thickness of the polysilicon wiring layer may become thin and the electrical resistance thereof may be smaller than a desired value.

In addition, since the oxidation of the silicon layer is greatly influenced by the plasma intensity, if there is a variation in the in-plane distribution of the plasma intensity, the variation occurs in the film thickness of the plasma silicon oxide layer. The film thickness distribution of the silicon oxide film (ALD silicon oxide film) by adsorption, oxidation, and plasma irradiation is almost identical to the in-plane distribution of plasma intensity because Si-OH bonds are uniformly formed by active hydrogen species as described above. Almost unaffected. However, when the ALD silicon oxide film is thin, even if the film thickness of the ALD silicon oxide film is uniform, the variation in the film thickness of the plasma silicon oxide layer based on the plasma intensity distribution becomes dominant, so that the film thickness on the appearance of the ALD silicon oxide film is uniform. The properties deteriorate (relatively large deviations may occur in the total film thickness of the ALD silicon oxide film and the plasma silicon oxide layer).

From the above circumstances, it is understood that the oxidation of the underlying silicon layer (or wafer) needs to be suppressed. Therefore, in the present modification, after the silicon oxide film is formed by adsorption and oxidation, a silicon oxide film is formed on the wafer W by a cycle of adsorption, oxidation and plasma irradiation (ALD). According to this, it is possible to suppress the plasma from reaching the underlying silicon by the silicon oxide film formed by the adsorption and oxidation, and the generation of the plasma silicon oxide layer by the plasma can be suppressed.

Since the following experiment was performed in order to examine the preferable film thickness of the silicon oxide film obtained by the film forming by adsorption and oxidation, the experiment and the test result are demonstrated here.

(Experiment 1)

In this experiment, first, a plurality of bare wafers of silicon were prepared. For these bare wafers, removal of the native oxide film by hydrofluoric acid etchant and treatment with hydrogen peroxide (H ₂ O ₂ aq.) Are performed in advance, and as a result, about 1 nm of oxidation is performed on the surface thereof. The silicon layer is formed. On this bare wafer, a silicon oxide film was formed by adsorption and oxidation, and then a silicon oxide film was formed by a cycle of adsorption, oxidation and plasma irradiation. Here, the silicon oxide film during the cycle of adsorption, oxidation, and plasma irradiation was made constant at 100 nm, and five samples were prepared by changing the film thickness (between film formation) of the silicon oxide film by adsorption and oxidation, and the total of the silicon oxide films The film thickness was measured. In addition, the high frequency electric power supplied to the antenna 85 (FIG. 6 etc.) at the time of plasma irradiation was 3300W. Further, the flow rate of the gas introducing nozzle 92, the flow rate of the Ar gas supplied to the (FIG. 7) of the flow, the O ₂ gas to the 15000sccm and to 75sccm, NH ₃ gas was set to 45sccm.

12 is a graph showing the difference (incremental ΔT) between the measured value and the predetermined value of the total film thickness with respect to the film thickness of the silicon oxide film by adsorption and oxidation. For example, when the thickness of the silicon oxide by adsorption and oxidation is zero (when not forming silicon oxide by adsorption and oxidation), the predetermined value of the total film thickness is 101 nm (film thickness of the silicon oxide film by hydrogen peroxide treatment). (Including 1 nm), as shown in the graph of Fig. 12, the measured value of the total film thickness is about 1.45 nm thicker than the predetermined value. It is thought that the result is that the bare wafer is oxidized by the plasma and the plasma silicon oxide layer is formed when the silicon oxide film is formed by forming a thick silicon oxide film. Specifically, when the thickness of the silicon oxide film by adsorption and oxidation is 1.2 nm, the increment ΔT becomes minimum, and slightly increases when the thickness exceeds 1.2 nm to 1.45 nm. When the thickness of the silicon oxide film by adsorption and oxidation exceeds 1.2 nm, the increase in the increment? T increases when the silicon oxide film is formed by adsorption and oxidation. It is considered that the amount of ozone diffused to the bare wafer is increased, but since the increment? T is constant even if the thickness of the silicon oxide film is increased by adsorption and oxidation, the amount of diffusion of ozone to the bare wafer is saturated. In addition, the oxidation of the bare wafer by plasma irradiation is also considered to be suppressed.

(Experiment 2)

In Experiment 2, the film thickness of the silicon oxide film by adsorption and oxidation was made constant (1.2 nm in which increment ΔT was minimum in Experiment 1), and the film formation time of the silicon oxide film by adsorption, oxidation, and plasma irradiation was changed. A plurality of samples were produced. In addition, the high frequency electric power at the time of plasma irradiation was 3300W. Further, the flow rate of the gas introducing nozzle 92, the flow rate of the Ar gas supplied to the (FIG. 7) of the flow, the O ₂ gas to the 15000sccm and to 75sccm, NH ₃ gas was set to 45sccm.

Fig. 13 is a graph showing the change in the film thickness thereof with respect to the deposition time of the silicon oxide film by adsorption, oxidation and plasma irradiation. As shown in the figure, it can be seen that the film thickness of the silicon oxide film increases linearly with the increase of the film formation time. Here, the deposition time is x and the film thickness y is based on the least square method from the result of the graph in FIG.

&Quot; (1) "

y = 1.80x + 2.57

&Quot; (2) "

R ² = 1

Results are obtained. The value of 2.57 nm of the y-intercept of Equation 1 is generated on the bare wafer when plasma is irradiated to the silicon oxide film by adsorption and oxidation without forming a silicon oxide film by adsorption, oxidation and plasma irradiation. It corresponds to the film thickness of a silicon oxide film. As described above, the thickness of the silicon oxide film formed on the surface of the bare wafer by pretreatment using hydrogen peroxide water is 1 nm, and the film thickness of the silicon oxide film formed by adsorption and oxidation is 1.2 nm. It can be seen that the increment ΔT of becomes about 0.4 nm {= 2.57- (1 + 1.2)}. In other words, it is thought that the plasma silicon oxide film is formed by passing through the silicon oxide film by adsorption and oxidation and the silicon oxide film by hydrogen peroxide, and the bare wafer is oxidized to form a plasma silicon oxide layer having a film thickness of about 0.4 nm. .

Further, as shown in Equation 2, since the square of the correlation coefficient R is 1, it can be seen that the film thickness can be controlled with high precision by the film formation time.

(Experiment 3)

Next, the result of having investigated the in-plane uniformity of the said total film thickness with respect to the total film thickness (measured value) of a silicon oxide film is demonstrated. A silicon oxide film by adsorption and oxidation having a thickness of 1.2 nm is formed on a bare wafer treated with hydrogen peroxide, and silicon oxide is subjected to a cycle of adsorption, oxidation, and plasma irradiation, so that the total thickness is 3 nm, 6 nm, and 9 nm, respectively. Three samples were produced by forming a film. For each of the samples, the total film thickness was measured at 49 points in the wafer plane, and the average film thickness and the deviation thereof were determined. The results are shown in Table 1 below.

As shown in Table 1, it can be seen that when the total film thickness increases from 3 nm to 9 nm, the film thickness uniformity in the wafer plane is remarkably improved. This result means that the film thickness uniformity of the silicon oxide film on the outermost surface of the bare wafer is significantly improved as the silicon oxide film formed by the cycle of adsorption, oxidation and plasma irradiation becomes thicker. Therefore, it is considered that the film thickness uniformity in the wafer surface of the silicon oxide film by the cycle of adsorption, oxidation and plasma irradiation is particularly excellent.

In addition, when the total film thickness is 3 nm, the film thickness of the plasma silicon oxide layer by oxidation of the bare wafer is 0.4 nm, the film thickness of the silicon oxide film by hydrogen peroxide treatment is 1 nm, and the silicon oxide film by adsorption and oxidation Since the film thickness is 1.2 nm, the film thickness of the silicon oxide film due to the cycle of adsorption, oxidation and plasma irradiation is 0.4 nm. In this case, it is substantially equivalent to deposit a silicon oxide film by adsorption and oxidation having a film thickness of 1.6 nm and to irradiate the silicon oxide film with the plasma. In the case of the total film thickness of 3 nm of experiment 3, the silicon oxide film by adsorption and oxidation which has a film thickness of 1.6 nm was deposited, and plasma irradiation was performed on the conditions similar to experiment 2.

The present invention has been described above with reference to some embodiments and examples, but the present invention is not limited to the above-described embodiments and examples, and various modifications or changes are possible in light of the appended claims.

For example, in the above-described embodiment, the plasma generation source 80 is configured as a so-called inductively coupled plasma (ICP) source having an antenna 85, but may be configured as a capacitively coupled plasma (CCP) source. Also in this case, since the activated hydrogen is generated from the NH ₃ gas by the plasma, and the OH group can be formed on the surface of the wafer W, the above-described effect is exerted.

Further, by being of the OH groups are generated on the silicon oxide film is the outermost surface film formation, since the absorption of the Si-containing gas can be promoted, and may be used for H ₂ gas instead of NH ₃ gas. It is also possible to use NH ₃ gas and H ₂ gas both. In addition, a person that is capable of forming an OH gas, NH ₃ gas and H ₂ is not limited to a gas, such as H ₂ O _{(water), H 2 N-NH 2} ( hydrazine), H ₂ O ₂ (hydrogen peroxide ) May be used.

In addition, in the above-described embodiment, the Si-containing gas is adsorbed onto the wafer W (hereinafter, simply adsorbed), the oxidation (hereinafter simply referred to as oxidation) by the O ₃ gas of the Si-containing gas adsorbed onto the wafer W and the plasma generation source ( 80) it was carried out with, for each one rotation of the modified rotary table (2) using a mixed gas of Ar gas, O ₂ gas and NH ₃ gas is activated by, but not limited to this. For example, modification of the silicon oxide film (hereinafter, simply modified) by the mixed gas of the activated Ar gas and O ₂ gas, and OH at the outermost surface of the silicon oxide film by the mixed gas of the activated Ar gas and NH ₃ gas Formation of a group (hereinafter, surface modification) may be performed separately. That is, in the period in which the rotary table 2 is rotated a plurality of times, adsorption, oxidation, and surface modification are performed for each revolution of the rotary table 2, and in the next few revolutions, one of the rotary tables 2 is rotated. Only modification may be performed for each rotation. Even in this case, since the OH group can be generated on the outermost surface of the wafer W by the mixed gas of the activated Ar gas and the NH ₃ gas, adsorption of the Si-containing gas is promoted, and it is possible to avoid a decrease in the film formation rate. . In addition, the deposited silicon oxide film can be made of high quality by reforming with a mixed gas of activated Ar gas and O ₂ gas, that is, through high purity and rearrangement with active oxygen species.

Further, with respect to in the above embodiment, Ar gas, O ₂ gas and NH but supply a mixed gas of the _third gas in the inner space S from the gas introduction nozzle (92), Ar gas, O ₂ gas and NH ₃ gas respectively, You may provide a gas introduction nozzle.

According to the embodiment of the present invention, there is provided a film forming method and a film forming apparatus capable of depositing a thin film having excellent film thickness distribution and film quality while maintaining the film forming speed.

Claims (14)

Loading a substrate into a vacuum container and loading the substrate on a rotary table provided to be rotatable in the vacuum container;
Rotating the rotary table;
Supplying a first reaction gas to the substrate from a first reaction gas supply unit, adsorbing the first reaction gas to the substrate,
A second reaction gas that reacts with the first reaction gas is supplied from the second reaction gas supply unit to the substrate, and the first reaction gas adsorbed on the substrate reacts with the second reaction gas on the substrate. To form the reaction product,
Hydrogen-containing gas is supplied from the first and second reactive gas supply units to a plasma generating unit provided spaced apart in the circumferential direction of the rotary table to generate a plasma above the rotary table, and plasma is supplied to the reaction product. And a adsorption-forming-irradiation step of irradiation. The film-forming method of Claim 1 whose said hydrogen containing gas is one or both of hydrogen gas and ammonia gas. The film forming method according to claim 1, wherein in the adsorption-forming-irradiating step, argon gas is supplied to the plasma generating unit. The argon gas according to claim 1, wherein in the adsorption-forming-irradiation step, argon gas is supplied to the plasma generating unit,
The hydrogen-containing gas is ammonia gas,
A film forming method in which the ratio of the supply amount of the ammonia gas to the supply amount of the argon gas is in the range of 0.15% to 0.75%. The argon gas according to claim 1, wherein in the adsorption-forming-irradiation step, argon gas is supplied to the plasma generating unit,
The hydrogen-containing gas is ammonia gas,
A film forming method, wherein the ratio of the supply amount of the ammonia gas to the supply amount of the argon gas is in the range of 0.3% to 0.5%. The method of claim 1, wherein prior to the adsorption-forming-irradiation step,
Supplying the first reaction gas to the substrate from the first reaction gas supply unit, adsorbing the first reaction gas to the substrate,
The second reaction gas is supplied from the second reaction gas supply unit to the substrate to react with the first reaction gas, and the first reaction gas adsorbed onto the substrate reacts with the second reaction gas, And a forming step of forming a reaction product on the substrate. The method of claim 6, wherein the thickness of the reaction product formed on the substrate in the forming step is determined so that the plasma does not reach the substrate in the adsorption-forming-irradiation step. A rotary table including a substrate mounting portion on which a substrate is loaded, the rotary table being rotatable in a vacuum container;
A first reaction gas supply unit for supplying a first reaction gas to the substrate mounted on the substrate loading unit and adsorbing the first reaction gas on the substrate,
It is provided spaced apart from the first reaction gas supply part in the circumferential direction of the turntable, supplies a second reaction gas to the substrate, and reacts the first reaction gas adsorbed on the substrate with the second reaction gas. A second reactive gas supply unit forming a reaction product on the substrate;
A plasma generator that is spaced apart from the first and second reactive gas supply parts in the circumferential direction of the rotary table, and generates plasma above the rotary table;
And a gas supply pipe for supplying a hydrogen-containing gas to the plasma generating unit. The said plasma generating part opens to the surface of the said rotary table, and has a member which comprises the space which produces the plasma between the said surfaces,
The film forming apparatus, wherein the gas supply pipe supplies the hydrogen-containing gas to the space. The film forming apparatus according to claim 8, wherein the plasma generating unit includes an inductively coupled plasma source having a coil to which high frequency power is supplied. The film-forming apparatus of Claim 8 whose said hydrogen containing gas is one or both of hydrogen gas and ammonia gas. The film-forming apparatus of Claim 8 which further contains the argon gas supply source which supplies an argon gas to the said space. The film-forming apparatus of Claim 12 whose ratio of the supply amount of the said ammonia gas with respect to the supply amount of the said argon gas is in the range from 0.15% to 0.75%. The film-forming apparatus of Claim 12 whose ratio of the supply amount of the said ammonia gas with respect to the supply amount of the said argon gas is in the range from 0.3% to 0.5%.

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