JP2007281082A - Film formation method, film-forming device, and storage medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique for improving in-plane uniformity for a film thickness when film-forming a thin film on a substrate by alternately supplying first feed gas and second feed gas by using a vertical heat-treating apparatus. <P>SOLUTION: In a process, the first feed gas is supplied into a reaction vessel for allowing the surface of the substrate to adsorb the first feed gas, then the second feed gas reacting with the first feed gas is supplied into the reaction vessel, and the feed gas supplied into the reaction vessel is switched for a plurality of times between the first feed gas and the second feed gas. In the process, hydrogen gas is supplied into the reaction vessel when at least one of the first feed gas and the second feed gas is being supplied into the reaction vessel. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention stores a film forming method and a film forming apparatus for forming a film on a plurality of substrates held in parallel with a substrate holder in a reaction vessel, and a computer program for executing the film forming method. Related to the storage medium.

  In the manufacturing process of a semiconductor device, since integration and thinning of devices are progressing, it is required to form a thin film with high accuracy. Therefore, as one of the film forming processes, the first source gas is adsorbed on the substrate, and then the processing atmosphere is evacuated, and then the second source gas is adsorbed on the substrate, and the components of the first source gas and the second The molecular layer is formed by reacting the components of the source gas on the substrate to form a molecular layer as a reaction product, and then adsorbing the first source gas and the second source gas alternately on the substrate. A method of stacking in multiple layers is known. According to this method, there is an advantage that the film thickness can be accurately controlled by setting the number of repetitions of the adsorption process. For example, a silicon nitride film (hereinafter referred to as “SiN film”) has the same electrical characteristics as a silicon oxide film even when the physical film thickness is large because of its high relative dielectric constant. It is a useful film used for a cap film or the like. In the case where the SiN film is formed by the above-described method, for example, a silane-based gas and ammonia gas can be alternately supplied into the processing container.

By the way, from the viewpoint of improving the characteristics of the circuit element, a low temperature process is required in order to minimize the thermal history of the film formed in the previous step in the heat treatment process. From such a background, Patent Document 1 describes a technique for suitably implementing a SiN film using a vertical heat treatment apparatus. This apparatus is configured by combining a vertical reaction vessel into which wafer holders on which wafers W are placed in multiple stages are carried, and a mechanism for converting the processing gas into plasma. When forming a SiN film, as shown in the cross-sectional plan view of FIG. 10, first, dichlorosilane (DCS) gas is supplied from the injector 14 to the surface of the wafer W to be adsorbed, and then the reaction vessel 10. After the inside is evacuated, ammonia (NH ₃ ) gas is supplied from the injector 14 into the plasma generation vessel 13 where an electric field is generated to activate it, and the generated NH ₃ active species (radicals) are converted into the wafer W To react the DCS gas molecules adsorbed on the surface of the wafer W with the NH ₃ active species. Subsequently, after the inside of the reaction vessel 10 is evacuated, DCS gas is supplied from the injector 14 to the surface of the wafer W, and by repeating such a series of operations, a thin film of SiN film is laminated on the surface of the wafer W one by one. Then, a SiN film having a desired thickness is formed on the surface of the wafer W (molecular layer deposition method). This technique can form a SiN film on the surface of the wafer W without exposing the wafer W to such a high temperature, and is suitable for the demand for a low temperature process.

By the way, the above-described apparatus has the following problems. The wafer holder 11 is slowly rotated by a driving unit (not shown) during the process. This is for suppressing the deviation of the concentration of the active species of NH ₃ or the DCS gas between the surface near the injector 14 and the surface far from the injector 14 on the surface of the wafer W placed on the wafer holder 11. However, as shown in FIG. 10, the wafer holder 11 includes, for example, three columns 16 a, 16 b, and 16 c that hold the periphery of the wafer W, and these columns 16 a, 16 b, and 16 c are arranged in front of the injector 14. In the region A of the wafer W which is a shadow of the pillars 16a, 16b and 16c when viewed through the injector 14, the SiN film is thinner than the central region B, and the in-plane uniformity of the wafer W is deteriorated with respect to the film thickness. There is a problem. In particular, when NH ₃ active species are used, the active species are deactivated when they collide with the support columns 16a, 16b, and 16c, so that it is difficult for them to enter the shadows of the support columns 16a, 16b, and 16c. It is difficult to ensure sex.

JP 2004-343017 (FIG. 1)

  The present invention has been made under such circumstances, and an object of the present invention is to supply a first raw material gas and a second raw material gas alternately using a vertical heat treatment apparatus to form a thin film on a substrate. It is an object of the present invention to provide a technique for further improving the in-plane uniformity of the film thickness.

The present invention relates to a method of forming a film on a substrate by holding a plurality of substrates in parallel with each other on a substrate holder and carrying them into a reaction vessel, heating the inside of the reaction vessel and supplying a processing gas.
Supplying a first source gas into the reaction vessel, adsorbing the first source gas on the surface of the substrate, and then supplying a second source gas that reacts with the first source gas into the reaction vessel; The step of switching the source gas supplied into the reaction vessel in this way between the first source gas and the second source gas a plurality of times,
Supplying hydrogen gas into the reaction vessel when supplying at least one of the first source gas and the second source gas into the reaction vessel. And

  In the above film forming method, it is desirable that at least one of the first source gas and the second source gas is activated. A step of supplying a hydrogen gas into the reaction vessel and performing a purge process when discharging at least one of the first source gas and the second source gas in the reaction vessel. It is good also as a structure. In the film forming method, it is preferable that the first source gas is, for example, a silane-based gas, the second source gas is, for example, ammonia gas, and a silicon nitride film, for example, is formed on the substrate. .

In the present invention, a plurality of substrates are held in parallel with each other by a substrate holder and carried into a reaction vessel, the inside of the reaction vessel is heated by a heating means provided around the substrate, and a processing gas is supplied to the substrate. In a film forming apparatus for performing film formation,
First source gas supply means for supplying the first source gas into the reaction vessel;
A second source gas supply means for supplying a second source gas into the reaction vessel;
Hydrogen gas supply means for supplying hydrogen gas into the reaction vessel;
Evacuation means for evacuating the reaction vessel;
Supplying a first source gas into the reaction vessel, adsorbing the first source gas on the surface of the substrate, and then supplying a second source gas that reacts with the first source gas into the reaction vessel; In this way, the source gas supplied into the reaction vessel is switched a plurality of times between the first source gas and the second source gas, and when the source gas is switched, the inside of the reaction vessel is evacuated, and the first reaction gas is placed in the reaction vessel. A control unit that controls each means so as to supply hydrogen gas into the reaction vessel when supplying at least one source gas of one source gas and the second source gas. It is characterized by.

Furthermore, in the present invention, a plurality of substrates are held in parallel with each other by a substrate holder and carried into a reaction vessel, the inside of the reaction vessel is heated by a heating means provided around the substrate, and a processing gas is supplied to the substrate. A storage medium for storing a computer program used in a film forming apparatus for forming a film,
The computer program includes a group of steps so as to execute the film forming method described above. Examples of the storage medium include a hard disk, a flexible disk, a compact disk, a magnetic optical disk (MO), and a memory card.

According to the present invention, when a first raw material gas such as dichlorosilane (DCS) gas and a second raw material gas such as ammonia (NH ₃ ) gas are supplied into the reaction vessel, a diffusion action is produced in the reaction vessel. Since a large amount of hydrogen (H ₂ ) gas is supplied, these source gases or active species (for example, NH ₃ active species) are shaded by the support column of the substrate holder as viewed from the first gas supply means. In addition, the film formation process with high in-plane uniformity can be performed.

  A film forming apparatus according to an embodiment of the present invention will be described. FIG. 1 and FIG. 2 are a schematic longitudinal sectional view and a schematic transverse sectional view of a batch type film forming apparatus comprising a vertical heat treatment apparatus, respectively. 2 in FIG. 1 and FIG. 2 is a reaction vessel formed of, for example, quartz in a vertical cylindrical shape, and a ceiling plate 21 made of quartz is provided on the ceiling in the reaction vessel 2 and sealed. Yes. Further, a flange 22 is integrally formed at the peripheral edge of the lower end opening of the reaction vessel 2, and a manifold 3 formed in a cylindrical shape with, for example, stainless steel is formed on the lower surface of the flange 22 such as an O-ring. It is connected via a seal member 31.

  The lower end of the manifold 3 is opened as a loading / unloading port (furnace port), and a flange 33 is formed integrally with the peripheral portion of the opening 32. Below the manifold 3, the opening 32 is hermetically closed on the lower surface of the flange 33 via a sealing member 34 such as an O-ring. For example, a lid 4 made of quartz can be opened and closed vertically by a boat elevator 41. Is provided. A rotation shaft 42 is provided through the central portion of the lid 4, and a wafer boat 5 serving as a substrate holder is mounted on the upper end portion of the rotation shaft 42.

  This wafer boat 5 includes three or more, for example, three support columns 51, and supports a plurality of, for example, 125 wafers W to be processed in a shelf shape by supporting each outer edge portion. As shown in FIG. 3, a groove 52 (slot) is formed in the support column 51. A motor M that forms a drive unit for rotating the rotary shaft 42 is provided below the rotary shaft 42, so that the wafer boat 5 is rotated by the motor M. A heat insulating unit 43 is provided on the lid 4 so as to surround the rotating shaft 42.

An L-shaped first source gas supply pipe 60 is inserted in the side wall of the manifold 3, and at the tip of the first source gas supply pipe 60, as shown in FIG. Two first source gas supply nozzles 61 made of a quartz tube extending upward in the reaction vessel 2 are arranged with an elongated opening 81 of a plasma generation unit 80 described later interposed therebetween. In these first source gas supply nozzles 61, 61, a plurality (a large number) of gas discharge holes 61a are formed at predetermined intervals along the length direction, and the gas discharge holes 61a, 61a Gas can be discharged substantially uniformly in the horizontal direction. Further, a supply source of a silane-based gas, for example, SiH ₂ Cl ₂ (dichlorosilane: DCS) gas, which is the first source gas, is provided on the base end side of the first source gas supply pipe 60 via a supply device group 62. 63 is connected.

Further, an L-shaped second source gas supply pipe 70 is inserted in the side wall of the manifold 3, and the inside of the reaction vessel 2 is provided at the tip of the second source gas supply pipe 70. A second source gas supply nozzle 71 made of a quartz tube that extends upward and bends in the middle and is installed in a plasma generator 80 described later is provided. In the second source gas supply nozzle 71, a plurality of (many) gas discharge holes 71a are formed at predetermined intervals along the length direction thereof, and are directed from the gas discharge holes 71a in the horizontal direction. The gas can be discharged almost uniformly. Further, the base end side of the second source gas supply pipe 70 is branched into two, and one second source gas supply pipe 70 is supplied with ammonia as a second source gas via a supply device group 72. A supply source 73 of (NH ₃ ) gas is connected, and a supply source 75 of hydrogen (H ₂ ) gas is connected to the other second source gas supply pipe 70 via a supply device group 74. The supply device groups 62, 72, and 74 are configured by valves, a flow rate adjusting unit, and the like.

  A plasma generation unit 80 is provided along a height direction of a part of the side wall of the reaction vessel 2. The plasma generation unit 80 forms a vertically elongated opening 81 by scraping the side wall of the reaction vessel 2 with a predetermined width along the vertical direction, and forms a recess in a cross section so as to cover the opening 81. The partition wall 82 made of, for example, quartz that is vertically elongated is hermetically welded to the outer wall of the reaction vessel 2. The opening 81 is formed long enough in the vertical direction so as to cover all the wafers W held by the wafer boat 5 in the height direction. A pair of elongated plasma electrodes 83 are provided on the outer surfaces of both side walls of the partition wall 82 so as to face each other along the length direction (vertical direction). The plasma electrode 83 is connected to a high-frequency power source 84 for generating plasma via a power supply line 85 so that plasma can be generated by applying a high-frequency voltage of 13.56 MHz, for example, to the plasma electrode 83. It has become. An insulating protective cover 86 made of, for example, quartz is attached to the outside of the partition wall 82 so as to cover it.

  In addition, on the opposite side of the reaction vessel 2 facing the plasma generator 80, an elongated exhaust port formed by, for example, scraping the side wall of the processing vessel 2 in the vertical direction in order to evacuate the atmosphere in the reaction vessel 2. 88 is formed. An exhaust cover member 89 made of quartz and having a U-shaped cross section is attached to the exhaust port 88 by welding so as to cover it. The exhaust cover member 89 extends upward along the side wall of the reaction vessel 2 so as to cover the upper side of the reaction vessel 2, and a gas outlet 90 is provided on the ceiling side of the exhaust cover member 89. Is formed. Connected to the gas outlet 90 is a vacuum pump 91 that constitutes a vacuum evacuation means capable of evacuating the reaction vessel 2 to a desired degree of vacuum, and an exhaust pipe 93 provided with a pressure adjusting unit 92 such as a butterfly valve. .

  As shown in FIG. 1, a cylindrical heater 94 is provided as a heating means for heating the reaction vessel 2 and the wafer W in the reaction vessel 2 so as to surround the outer periphery of the reaction vessel 2. As the heater 94, a carbon wire or the like having no contamination and having excellent temperature rising / falling characteristics is used.

  In addition, the plasma processing apparatus includes a control unit 9, and the control unit 9 includes, for example, a computer, and controls the boat elevator 41, the heater 94, the supply device groups 62, 72, 74, the pressure adjustment unit 92, and the like. It is configured. More specifically, the control unit 9 stores a sequence program for executing a series of processing steps to be described later performed in the reaction vessel 2, reads instructions of each program, and sends a control signal to each unit. A means for outputting is provided. The program is stored in the control unit 9 in a state of being stored in a storage medium such as a hard disk, a flexible disk, a compact disk, a magnetic optical disk (MO), or a memory card.

Next, the operation of the above embodiment will be described. First, in this example, a large number of wafer boats 5 each having 50 300 mm size wafers W placed in multiple stages are raised from below into a reaction vessel 2 set at a predetermined temperature and loaded (loaded). Then, the inside of the reaction vessel 2 is sealed by closing the lower end opening 32 of the manifold 3 with the lid 4. Then, the inside of the reaction vessel 2 is evacuated by the vacuum pump 91 so that the inside of the reaction vessel 2 has a predetermined degree of vacuum. Next, the pressure in the reaction vessel 2 is set to, for example, 666.5 Pa (5 Torr), and DCS gas and H ₂ gas are supplied into the reaction vessel 2 from the first source gas supply nozzle 60 at a flow rate of, for example, 1000 sccm and 2000 sccm, for 3 seconds, for example. DCS gas molecules are adsorbed on the surface of the wafer W which is supplied and held in a shelf shape of the rotating wafer boat 5 (step 1).

The H ₂ gas supplied into the reaction vessel 2 has a much smaller molecular size than the DCS gas. Therefore, the H ₂ gas has a large diffusing action. Therefore, since DCS gas also diffuses with the diffusion of H ₂ gas, it spreads to every corner in the reaction vessel 2 as shown in FIG. Therefore, although the wafer boat 5 is rotated by the motor M, the DCS gas sufficiently flows into the shadowed area of the column 51 of the wafer boat 5 when viewed from the first gas supply nozzle 60, and as a result, the wafer W An adsorbed layer of DCS gas molecules is formed with high uniformity on the surface.

Thereafter, the supply of DCS gas is stopped, the H ₂ gas is continuously supplied into the reaction vessel 2, and the pressure in the reaction vessel 2 is set to 120 Pa (0.9 Torr), for example, and the reaction vessel 2 is purged with H ₂ ( Step 2). In this case, as described above, the DCS gas is surely discharged without staying in the reaction vessel 2 due to the large diffusion action of the H ₂ gas.

Next, the pressure in the reaction vessel 2 is set to 93 Pa (0.7 Torr), for example, and NH ₃ gas and H ₂ gas are supplied into the reaction vessel 2 from the second source gas supply nozzle 71 at flow rates of, for example, 5000 sccm and 2000 sccm, respectively. Supply is performed with the high-frequency power supply 84 turned off for 1 second (step 3). Thereafter, while maintaining the degree of vacuum, NH ₃ gas and H ₂ gas are supplied into the reaction vessel 2 at a flow rate of, for example, 5000 sccm and 2000 sccm for 15 seconds, for example, with the high-frequency power supply 84 turned on. For example, active species such as N radicals, NH radicals, NH ₂ radicals, and NH ₃ radicals are adsorbed (step 4). On the surface of the wafer W, DCS gas molecules react with NH ₃ active species to form a silicon nitride film (SiN film). Since the inside of the reaction vessel 2 supplies H ₂ simultaneously with the NH ₃ gas, the NH ₃ gas is sufficiently supplied to the shadowed area of the column 51 of the wafer boat 5 as seen from the second gas supply nozzle 71 as described above. ₃ gas wraps around. Further, since the DCS gas floating in the reaction vessel 2 is surely exhausted, there is no possibility that an unscheduled SiN film is deposited on the surface of the wafer W by reacting with the floating DCS gas. A SiN film is formed on the surface of W with high in-plane uniformity.

Thereafter, the supply of NH ₃ gas is stopped, the supply of H ₂ gas into the reaction vessel 2 is continued, and the pressure in the reaction vessel 2 is set to 106 Pa (0.8 Torr), for example, and the inside of the reaction vessel 2 is purged with H _2. (Step 5). Similarly, the NH ₃ gas remaining in a floating state in the reaction vessel 2 is reliably discharged without being retained in the reaction vessel 2 due to the large diffusion action of the H ₂ gas. Then, as shown in FIG. 5, by repeating Step 1 to Step 5 a plurality of times, for example, 200 times, a thin film of SiN film is laminated on the surface of the wafer W one by one, and a SiN film having a desired thickness is formed on the surface of the wafer W. Formed (molecular layer deposition). Further, the adjustment of the valves and the flow rate adjustment unit of the supply device groups 62, 72 and 74 and the adjustment of the pressure adjustment unit 92 in a series of steps are performed based on a program stored in the control unit 9.

According to the above-described embodiment, when dichlorosilane (DCS) gas and ammonia (NH ₃ ) gas are supplied into the reaction vessel 2, hydrogen (H ₂ ) having a large diffusion action in the reaction vessel 2. Since the gas is supplied, the active species of DCS gas and NH ₃ are shadowed by the column 51 of the wafer boat 5 as seen from the first source gas supply nozzle 61 and the second gas supply nozzle 71 as described above. Therefore, the SiN film can be uniformly formed on the surface of the wafer W as shown in an example described later.

Further, according to the above-described embodiment, when the DCS gas and the NH ₃ gas source gas are discharged into the reaction vessel 2, the DCS gas and NH ₃ gas remaining in the reaction vessel 2 are efficiently used as described above. It can be discharged well, and the film formation uniformity can be further improved. In particular, when using activated species of NH ₃ gas, it is caused by the collision with the column 51 of the wafer boat 5 and dead life, particularly in the region that becomes a shadow of the column 51 when viewed from the second source gas supply nozzle 71. Although the film thickness is reduced, this tendency is mitigated by using H ₂ gas, which is extremely effective.

Further, the H ₂ gas may be supplied into the reaction vessel 2 only when either DCS gas or NH ₃ gas is supplied into the reaction vessel 2.

In the above embodiment, the DCS gas is used as the silane-based gas. However, the present invention is not limited to this, and other silane-based gas may be used. Examples of other silane gases include monosilane (SiH ₄ ), disilane (Si ₂ H ₆ ), hexachlorodisilane (HCD), hexamethyldisilazane (HMDS), tetrachlorosilane (TCS), disilylamine (DSA), trisilane. Silylamine (TSA), Vistabutylbutylaminosilane (BTBAS), etc. can also be used.

  Next, an experiment conducted for confirming the effect of the present invention will be described.

Example 1
A silicon nitride film was formed on the surface of the wafer W by repeating the above-described Step 1 to Step 5 a plurality of times, for example, 500 times, using the film forming apparatus shown in FIGS. As a film forming gas, DCS (SiH ₂ Cl ₂ ) gas and NH ₃ gas were used. The process conditions are as described in the previous embodiment.

(Example 2)
In Example 1, in the process of supplying NH ₃ gas into the reaction vessel 2 at a flow rate of 5000 sccm, and the _{N 2} gas is supplied in place of the _{H 2} gas and the subsequent purging process in place of the _{H 2} gas _{N 2} A silicon nitride film was formed on the surface of the wafer W in the same manner as in Example 1 except that the gas was used.

(Comparative example)
In Example 1, when DCS gas and NH ₃ gas were supplied into the reaction vessel 2, N ₂ gas was supplied instead of H ₂ gas, and the purge process in the reaction vessel 2 was performed with N ₂ gas. Otherwise, a silicon nitride film was formed on the surface of the wafer W in the same manner as in Example 1.
(Inspection method)
After forming a SiN film on the surface of the wafer W, the wafer boat 5 is unloaded from the reaction vessel 2, and the wafer (TOP) placed on the upper stage of the wafer boat 5 is placed on the middle stage of the wafer boat 5. One wafer (CTR) and one wafer (BTM) placed on the lower stage of the wafer boat 5 were taken out, and the in-plane uniformity of the film thickness of each wafer (TOP, CTR, BTM) was examined. Here, in-plane uniformity means ((maximum film thickness-minimum film thickness) / (2 × average film thickness)) × 100%. In addition, in the SiN film formed on the surface of each wafer (TOP, CTR, BTM), the deposition rate at which the SiN film was formed on the surface of the wafer W was also examined.
(Results and discussion)
In FIG. 6, the result of Example 1, Example 2, and a comparative example is shown. In FIG. 6, the bar graph indicates the film formation rate, and the line graph indicates the uniformity of the film thickness of the SiN film. As shown in FIG. 6, in Example 1 and Example 2, the uniformity of the film thickness of the SiN film is improved compared to the comparative example, and the film formation rate for forming the SiN film on the surface of the wafer W is higher. It can be seen that it has increased. When the uniformity of the SiN film is described in detail, as a result of measuring the film thickness with a film thickness measuring device at a plurality of points on the surface of the wafer W processed in Example 1, Example 2 and Comparative Example, as shown in FIG. In each of Example 1, Example 2, and Comparative Example, on the surface of the wafer W, the portion A that is a shadow of the support column 51 has a thinner SiN film than the central part B. However, Examples 1 and 2 are comparative examples. It was found that the difference between the film thickness of the SiN film formed in the portion A which is a shadow of the support column 51 and the film thickness of the SiN film formed in the central part B is small. From this, it can be understood that it is effective to supply H ₂ gas into the reaction vessel 2 instead of N ₂ gas. Further, in Example 1, the difference in film thickness between the SiN film formed in the central portion of the wafer W and the SiN film formed in the peripheral portion of the wafer W is smaller than that in the second embodiment. container also supplied H ₂ gas into the 2 when supplying the NH ₃ gas not only during the supply of the DCS gas and also a still more effective to perform with H ₂ gas during the purging process the reaction vessel 2 I can understand.

  Further, the SiN film formed on the surface of the wafer W was immersed in a hydrofluoric acid solution, and the etching rate of the SiN film with respect to hydrofluoric acid was examined (wet etching). The result is shown in FIG. As shown in FIG. 8, the etching rate of Example 1 was 13.37, the etching rate of Example 2 was 13.86, and the etching rate of the comparative example was 15.15. From this result, it is estimated that in Example 1 and Example 2, the SiN film formed on the surface of the wafer W is denser than in the comparative example.

The composition of the SiN film formed on the surface of the wafer W was also measured using a secondary ion mass spectrometer (SIMS). The result is shown in FIG. The vertical axis in FIG. 9 indicates the concentration (atoms / cm ³ ), and the horizontal axis indicates H atoms, C atoms, O atoms, and Cl atoms contained in the SiN film. As shown in FIG. 9, it can be seen that Example 1, Example 2, and Comparative Example do not have a significant change in the quality of the SiN film. From the above, it can be seen that the present invention can form a SiN film having a composition equivalent to the conventional one and slightly good film quality with high in-plane uniformity.

It is a schematic longitudinal cross-sectional view which shows an example of the plasma processing apparatus which concerns on embodiment of this invention. It is a schematic cross-sectional view which shows an example of the plasma processing apparatus of implementation of this invention. It is the schematic which shows the wafer boat which is a part of the said plasma processing apparatus. It is explanatory drawing which shows a mode that a gas flows in the surface of the wafer mounted in the said wafer boat. It is explanatory drawing which shows the timing of supply of various gas. It is a characteristic view which shows the result of the experiment example performed in order to confirm the effect of this invention. It is a figure which shows the mode of the wafer W surface in the experiment example performed in order to confirm the effect of this invention. It is a characteristic view which shows the result of the experiment example performed in order to confirm the effect of this invention. It is a characteristic view which shows the result of the experiment example performed in order to confirm the effect of this invention. It is the schematic longitudinal cross-sectional view and schematic cross-sectional view which show an example of a plasma processing apparatus.

Explanation of symbols

W Semiconductor wafer M Motor 2 Reaction vessel 3 Manifold 41 Boat elevator 5 Wafer boat 51 Post 60 First source gas supply pipe 61 First source gas supply nozzle 63 Silane-based gas supply source 70 Second source gas supply pipe 71 Second source gas supply nozzle 73 NH ₃ gas supply source 75 H ₂ gas supply source 80 Plasma generation unit 83 Plasma electrode 84 High frequency power supply 89 Exhaust cover member 9 Control unit 91 Vacuum pump 92 Pressure adjustment unit

Claims (9)

In a method in which a plurality of substrates are held in parallel with each other by a substrate holder and carried into a reaction vessel, the inside of the reaction vessel is heated and a processing gas is supplied to form a film on the substrate.
Supplying a first source gas into the reaction vessel, adsorbing the first source gas on the surface of the substrate, and then supplying a second source gas that reacts with the first source gas into the reaction vessel; The step of switching the source gas supplied into the reaction vessel in this way between the first source gas and the second source gas a plurality of times,
Supplying hydrogen gas into the reaction vessel when supplying at least one of the first source gas and the second source gas into the reaction vessel. A film forming method.   2. The film forming method according to claim 1, wherein at least one of the first source gas and the second source gas is activated.   And a step of performing a purging process by supplying hydrogen gas into the reaction vessel when discharging at least one of the first source gas and the second source gas in the reaction vessel. The film forming method according to claim 1, wherein:   4. The method according to claim 1, wherein the first source gas is a silane-based gas, the second source gas is an ammonia gas, and a silicon nitride film is formed on the substrate. The film-forming method as described in one. A plurality of substrates are held in parallel with each other by a substrate holder and carried into a reaction vessel, and the inside of the reaction vessel is heated by heating means provided around the substrate and a processing gas is supplied to form a film on the substrate. In the film forming apparatus,
First source gas supply means for supplying the first source gas into the reaction vessel;
A second source gas supply means for supplying a second source gas into the reaction vessel;
Hydrogen gas supply means for supplying hydrogen gas into the reaction vessel;
Evacuation means for evacuating the reaction vessel;
Supplying a first source gas into the reaction vessel, adsorbing the first source gas on the surface of the substrate, and then supplying a second source gas that reacts with the first source gas into the reaction vessel; In this way, the source gas supplied into the reaction vessel is switched a plurality of times between the first source gas and the second source gas, and when the source gas is switched, the inside of the reaction vessel is evacuated, and the first reaction gas is placed in the reaction vessel. A control unit that controls each means so as to supply hydrogen gas into the reaction vessel when supplying at least one source gas of one source gas and the second source gas. A film forming apparatus characterized by the above.   6. The film forming apparatus according to claim 5, further comprising an activating means for activating at least one of the first source gas and the second source gas.   When the controller discharges at least one of the first source gas and the second source gas in the reaction vessel, the control unit performs a purge process by supplying hydrogen gas into the reaction vessel. The film forming apparatus according to claim 5, wherein the film forming apparatus is controlled.   8. The method according to claim 5, wherein the first source gas is a silane-based gas, the second source gas is an ammonia gas, and a silicon nitride film is formed on the substrate. The film-forming apparatus as described in one. A plurality of substrates are held in parallel with each other by a substrate holder and carried into a reaction vessel, and the inside of the reaction vessel is heated by heating means provided around the substrate and a processing gas is supplied to form a film on the substrate. A storage medium for storing a computer program used in a film forming apparatus,
5. A storage medium in which the computer program includes a set of steps so as to execute the film forming method according to claim 1.

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