KR20000011360A - Single-substrate-heat-processing apparatus and method for performing reformation and crystallization - Google Patents

Abstract

PURPOSE: A sheet fed typed heat treating device is provided to improve a throughput and to reduce equipment cost and manufacturing cost. CONSTITUTION: A common returning chamber(3) of a film forming system(1) contains; two CVD devices(4, 6), a reforming device(8) and a heat treating device(10) being connected; and two cassette chambers(14A, 14B) connected for improving an efficiency of carrying in and out for a wafer. Therefore, the wafer is returned between each device and the cassette chambers through the common returning chamber while maintaining a vacuum state. In the heat treating device, the temperature of the wafer is raised from under the temperature of crystallizing of a metal oxide film to over the temperature of crystallizing in the state of the existence of an activated oxygen atom. Therefore, the reforming treatment of the metal oxide film formed on the top layer of the wafer and the crystallizing treatment of every metal oxide films filmed on the wafer are operated continuously.

Description

Single heat treatment apparatus and method for reforming and crystallization {SINGLE-SUBSTRATE-HEAT-PROCESSING APPARATUS AND METHOD FOR PERFORMING REFORMATION AND CRYSTALLIZATION}

The present invention relates to a sheet type heat treatment apparatus and method for performing a reforming treatment for removing organic impurities contained in a thin film disposed on a substrate to be processed and a crystallization treatment for crystallizing the thin film. In particular, it relates to a heat treatment apparatus and method for a metal oxide film deposited by MOCVD (Metal Organic Chemical Vapor Deposition).

When manufacturing a semiconductor device, a film formation process and a pattern etching process are performed repeatedly with respect to a semiconductor wafer. As the film forming process becomes more dense and highly integrated in semiconductor devices, the specifications thereof become stricter every year. For example, an extremely thin insulating film such as an insulating film or a gate insulating film of a capacitor is further thinned and a high insulating property is required.

As these insulating films, a silicon oxide film, a silicon nitride film and the like have conventionally been used. However, in recent years, metal oxide films such as tantalum oxide (Ta ₂ O ₅ ) films have been used as materials having better insulating properties. Such a film can be deposited by MOCVD, that is, by gasifying and using an organometallic compound. This metal oxide film can further improve insulation by performing a surface modification treatment after deposition. Japanese Patent Laid-Open No. 90-283022 discloses a modification treatment technique of this kind.

The formation of the tantalum oxide film is performed in a CVD apparatus. As the processing gas, for example, a source gas containing a tantalum alkoxide (Ta (OC ₂ H ₅ ) ₅ ) and an oxygen gas are used. Process pressure is set to about 0.2-0.3 Torr, and process temperature is set to about 250-450 degreeC. Under these conditions, the excitation species generated by dissociation of the source gas react with the oxygen gas so that the tantalum oxide film in an amorphous state (amorphous state) is formed on the semiconductor wafer. To be deposited.

The modification process of the tantalum oxide film after deposition is performed in the reforming apparatus. The wafer on which the tantalum oxide film is disposed is disposed in an atmospheric pressure atmosphere containing ozone. In order to generate active oxygen atoms, ozone is irradiated with ultraviolet rays from a mercury lamp. By active oxygen atoms, organic impurities such as C-C bonds contained in the tantalum oxide film are decomposed and released. As a result, the insulating properties of the tantalum oxide film are improved. The modification treatment is performed at a temperature below the crystallization temperature, for example, about 425 ° C, so as to maintain an amorphous state of the tantalum oxide film.

Next, the wafer is conveyed to the heat treatment apparatus for crystallization. Here, the tantalum oxide film is heated to a crystallization temperature or higher, for example 700 ° C., in the presence of oxygen gas. By this annealing, the tantalum oxide film is crystallized and densified at the molecular level, so that the insulating properties of the tantalum oxide film are further improved.

In addition, Japanese Patent Laid-Open No. 97-121035 discloses a technique of forming a tantalum oxide film in two layers. That is, first, an amorphous first layer is deposited on the semiconductor wafer, and the modification process is performed. Next, a second layer in an amorphous state is deposited on the first layer, and the modification process is performed. And finally, the wafer is heat treated at high temperature so that the first and second layers crystallize together. According to this technique, as each layer becomes thinner, organic impurities can be effectively removed at the time of each reforming process, and it becomes possible to improve the insulation characteristic of a tantalum oxide film further. However, this method has a problem that the throughput decreases while the number of processing steps and the number of transfer steps increases, while the equipment cost and the production cost increase.

Japanese Laid-Open Patent Publication No. 98-79377 (US Patent Application 08 / 889,590) relating to the invention of the inventors and the like discloses a cluster tool type film forming system in which a deposition apparatus, a reforming apparatus and a crystallization heat treatment apparatus are connected in a common transport chamber. Is disclosed. According to such a cluster tool type film forming system, the above-described problems such as throughput can be solved to some extent. However, further improvements are desired.

It is an object of the present invention to provide a single sheet heat treatment apparatus and method for performing modification and crystallization, which can improve throughput and reduce equipment cost and production cost.

In order to achieve the above object, the present invention provides a sheet type heat treatment apparatus and method having the configuration described in each section of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic block diagram which shows the principal part of the cluster tool type film formation system which concerns on the Example of this invention.

2A to 2D are diagrams showing a film forming method according to an embodiment of the present invention in the order of process;

3 is a graph showing a change in process temperature of a heat treatment apparatus;

4 is a graph showing the dielectric breakdown voltage characteristics of a tantalum oxide film;

5A to 5D show a film forming method according to another embodiment of the present invention in the order of process;

6A and 6B illustrate a film forming method according to still another embodiment of the present invention in the order of process;

7 is a schematic configuration diagram showing a main part of a heat treatment apparatus of the film forming system shown in FIG. 1;

8 is a plan view showing the shower head of the apparatus shown in FIG.

9 is a schematic configuration diagram showing a main part of a heat treatment apparatus according to another embodiment of the present invention;

10 is a schematic block diagram showing a main part of a cluster tool type film forming system according to another embodiment of the present invention;

11 is a schematic configuration diagram showing a main part of a heat treatment apparatus according to still another embodiment of the present invention;

12 is a graph showing a result of comparing the conventional method of performing modification with only ultraviolet rays and the method of the present invention performing modification using ultraviolet rays and infrared rays,

13 is a schematic configuration diagram showing a main part of a heat treatment apparatus according to still another embodiment of the present invention;

14 is a schematic plan view of the apparatus shown in FIG. 13;

15 is a graph showing a change in scanning speed of a light beam;

16 is a schematic structural diagram showing a main part of a heat treatment apparatus according to still another embodiment of the present invention;

17 is a schematic configuration diagram showing a main part of a heat treatment apparatus according to still another embodiment of the present invention;

18 is a schematic configuration diagram showing a main part of a heat treatment apparatus according to still another embodiment of the present invention;

19 is a schematic plan view of the apparatus shown in FIG. 18;

Explanation of symbols for the main parts of the drawings

1: film-forming system 3: common conveying chamber

4,6: CVD apparatus 8: reforming apparatus

10, 32, 72: heat treatment apparatus 14A, 14B: cassette seal

20,22,24: Tantalum oxide layer (metal oxide film)

34: treatment chamber 56: shower head

W: wafer

Best Mode for Carrying Out the Invention Embodiments of the present invention will be described below with reference to the drawings. In addition, in the following description, about the component which has substantially the same function and structure, the same code | symbol is attached | subjected and duplication description shall be made only when necessary.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram which shows the principal part of the cluster tool type film forming system which concerns on the Example of this invention.

As shown in FIG. 1, in the film formation system 1, two CVD apparatuses 4 and 6, a reforming apparatus 8, and a heat treatment apparatus 10 are connected to the common transfer chamber 3. do. In addition, two cassette chambers 14A and 14B are connected to the common transfer chamber 3 in order to improve the carrying in and out efficiency of the wafer. The wafer is conveyed through the common conveyance chamber 3, maintaining the vacuum state between each apparatus 4, 6, 8, 10, and cassette chamber 14A, 14B. In order to convey a wafer, in the common conveyance chamber 3, the arm mechanism 16 which consists of an articulated arm which can be stretched and swiveled is arrange | positioned.

The common transfer chamber 3 and the cassette chambers 14A and 14B are connected via the gate valves G1 and G2, respectively. In the cassette chambers 14A and 14B, gate doors G3 and G4 for opening and closing the opening and closing with the external work room atmosphere are respectively provided.

The common transfer chamber 3, the CVD apparatuses 4 and 6, the reforming apparatus 8, and the heat treatment apparatus 10 are connected via gate valves G5, G6, G7, and G8, respectively.

The common conveyance chamber 3 and the cassette chamber 14A, 14B are each comprised by airtight structure. The cassette chambers 14A and 14B constitute a wafer carrying in / out port of the entire film forming system. Through the open gate doors G3 and G4, a cassette C for accommodating a plurality of semiconductor wafers is carried in and out of the cassette chambers 14A and 14B. The cassette chambers 14A and 14B are each provided with a cassette stage (not shown) which is free to move up and down. The cassette chambers 14A and 14B can be vacuumed in the state where the cassette C was accommodated.

The CVD apparatuses 4 and 6 are used for forming a metal oxide film in an amorphous state in a vacuum atmosphere in which a metal oxide film raw material in a vaporized state and an oxidizing gas are present on a substrate to be processed, such as the semiconductor wafer W. FIG. The reforming apparatus 8 is used for exposing the metal oxide film to active oxygen atoms in a vacuum atmosphere to perform the reforming treatment. The heat treatment apparatus 10 is used to continuously carry out the modification process of the metal oxide film and the crystallization process of heating and crystallizing the metal oxide film above the crystal temperature.

Each unit (4, 6, 8, 10) and the common transfer chamber (3), a cassette chamber (14A, 14B), the gas supply for purging (purge) the interior with an inert gas such as N ₂ gas equipment (not shown ) And a vacuum exhaust mechanism (not shown) for evacuating the inside are respectively connected. The N ₂ gas supply and vacuum exhaust of each of the apparatuses 4, 6, 8, 10, the common transfer chamber 3, and the cassette chambers 14A, 14B can be controlled independently of each other.

As the CVD apparatuses 4 and 6 and the reforming apparatus 8, those disclosed in Japanese Patent Application Laid-Open No. 98-79377 (US Patent Application 08 / 889,590) can be used. The disclosure of this patent is incorporated herein by reference. In each of the CVD apparatuses 4 and 6, for example, a tantalum oxide (Ta ₂ O ₅ ) layer is deposited on the wafer surface as an amorphous metal oxide film by CVD. As the metal oxide film raw material, a liquid metal alkoxide, such as Ta (OC ₂ H ₅ ) _{5, which} is an organic compound, is bubbled and supplied, for example, by He gas. This processing gas gas and O ₂ , which is an oxidizing gas, are mixed gas in the processing chamber, and the CVD film-forming reaction is performed in this atmosphere. The reason for providing two CVD apparatuses of the same structure is to improve the throughput. As the oxidizing gas, in addition to O ₂ , O ₃ , N ₂ O, NO, an alcohol in a vaporized state, or the like can be used.

In the reforming apparatus 8, the surface of the wafer provided on the mounting target in which the heating heater is embedded is exposed to active oxygen atoms, and the metal oxide film formed on the surface of the wafer is modified. Active oxygen atoms are obtained by introducing ozone (O ₃ ) from the outside and irradiating ultraviolet rays from the lamp 18 of the ceiling of the device. In addition, instead of ozone, N ₂ O gas may be used to generate active oxygen atoms. The active oxygen atoms decompose and desorb organic impurities such as CC bonds and hydrocarbons present in the metal oxide film. This reforming process is performed at a temperature below the crystallization temperature of the metal oxide film in order to completely remove the organic impurities.

In the heat treatment apparatus 10, in the presence of active oxygen atoms, the wafer is heated up from the crystallization temperature of the metal oxide film to the crystallization temperature or more. Thereby, the modification process of the metal oxide film formed in the uppermost layer of a wafer, and the crystallization process of all the metal oxide films formed on the wafer are performed continuously. Or it is also possible to raise a wafer in presence of active oxygen atom, and to achieve a reforming process and a crystallization process at about the same time.

FIG. 7: is a schematic block diagram which shows the principal part of the apparatus 32 used as the heat processing apparatus 10 of the film formation system 1 shown in FIG.

As shown in FIG. 7, this heat treatment apparatus 32 has a processing chamber 34 formed of, for example, aluminum whose surface is covered with alumite. The bottom plate 38 is airtightly arranged at the bottom of the processing chamber 34 via a sealing member 36 such as an O-ring.

The mounting table 44 for mounting the semiconductor wafer W is disposed in the processing chamber 34. The mounting table 44 has a base 45 and a cover 46 detachably attached to the base 45 via the clamp 48. The cover 46 is made of light transmissive quartz, and a plurality of quartz pins 47 for mounting the wafer W are disposed thereon. An airtight space is formed between the base 45 and the cover 46 to be isolated from the atmosphere in the processing chamber 34.

In the airtight space of the mounting table 44, the some heating lamp 50 which consists of halogen lamps etc. is arrange | positioned. By the lamp 50, the wafer W can be heated from its back side. Since the electric power input to each lamp 50 can be controlled by the controller 51, it becomes possible to set the temperature of the wafer W and the metal oxide film arrange | positioned on it to arbitrary temperature. Under each lamp 50, a reflecting mirror 52 whose cross section forms a substantially elliptic or parabolic curve is disposed. Thereby, the radiation light from the lamp 50 can be irradiated to the back surface of a wafer efficiently.

In the bottom plate 38 of the processing chamber 34, a plurality of exhaust ports 54 connected to the vacuum exhaust mechanism 55 are formed. The vacuum exhaust mechanism 55 allows the inside of the processing chamber 34 to be exhausted and set to a vacuum. On the side wall of the processing chamber 34, a gate valve G7 that opens and closes when carrying in and out of the wafer W is disposed. On the upper side of the mounting table 44, the shower head 56 is disposed. The showerhead 56 is connected to the gas source 59 of the processing gas O ₃ or O ₂ via a line 58 passing through the side wall of the processing chamber 54.

The showerhead 56 has a lattice shape as shown in FIG. 8. That is, the showerhead 56 has a ring pipe 60A connected to the line pipe 58 and an inner pipe 60B connected to the inside thereof and woven in a grid. In the inner pipe 60B, a plurality of gas injection holes 61 are formed at the same pitch at the lower side.

In the ceiling plate 42 of the processing chamber 34, an opening having a diameter larger than the wafer diameter is formed. A window 64 made of light transmissive quartz is hermetically disposed through a sealing member 62 such as an O-ring so as to close the opening. A plurality of ultraviolet lamps 66 are arranged above the window 64. For example, 254 nm ultraviolet rays are generated from the lamp 66 and irradiated to the processing gas and the target surface of the wafer W through the window 64. As a result, active oxygen atoms are generated from the processing gas.

9 is a schematic configuration diagram showing a main part of another embodiment of the heat treatment apparatus 10.

As shown in FIG. 9, this heat processing apparatus 72 has the processing chamber 74 formed, for example with the aluminum whose surface was coat | covered with the alumite. In the heat treatment apparatus 72, the shower head 56, the window 64, and the ultraviolet lamp 66 like the apparatus shown in FIG. 7 are not arrange | positioned. Instead, the nozzle 78 connected to the gas source 59 of the processing gas O ₂ is connected to the ceiling plate 42 of the processing chamber 74 via the plasma cavity 76. In the plasma cavity 76, the processing gas is plasmaated by the power of the microwave power source 80. As a result, active oxygen atoms are supplied from the nozzle 78 into the processing chamber 72. Opposite the nozzle 78, a distribution plate 82 having a plurality of openings 84 is disposed. By the distribution plate 82, active oxygen atoms are uniformly supplied to the surface of the wafer.

Next, the film forming method of the present invention executed using the film forming system 1 shown in FIG. 1 will be described. Here, the case where the thin metal oxide film which consists of two layers as an insulating film is formed is demonstrated as an example.

First, the overall flow of the semiconductor wafer W, for example, an 8-inch wafer, will be described. The cassette C containing 25 unprocessed wafers W, for example, is mounted on a cassette stage (not shown) in the first cassette chamber 14A. Subsequently, the gate door G3 is closed to make the room an inert gas atmosphere of N ₂ gas, and the chamber 14 is vacuumed.

Next, the gate valve G1 is opened, and the inside of the cassette chamber 14A is evacuated in advance to communicate with the inside of the common transfer chamber 3 made of an inert gas atmosphere. The wafer W is loaded from the cassette chamber 14A using the arm mechanism 16 in the common transfer chamber 3.

Next, the wafer W is loaded into one CVD apparatus 4 which is evacuated in advance through the gate valve G5. Here, for example, a tantalum oxide (Ta ₂ O ₅ ) layer is deposited as the first layer of the insulating thin film. After completion of the deposition process of the first layer, the wafer W is output into the common transfer chamber 3 held in a vacuum state using the arm mechanism 16.

Next, the wafer W is carried into the reforming apparatus 8 which is previously vacuumed via the gate valve G6 opened. Here, by using ultraviolet rays or ozone generated from the ultraviolet irradiation means 18, organic impurities such as hydrocarbons and C-C bonds contained in the first tantalum oxide layer on the wafer surface are removed to perform the modification process.

After the modification process is completed, the wafer W is output into the common transfer chamber 3 held in a vacuum state by the arm mechanism 16. Next, the wafer W is brought into the second CVD apparatus 6 previously held in a vacuum state through the open gate valve G8, where the film forming process in the first CVD apparatus 4 and Under the same conditions, the second tantalum oxide layer is deposited.

After completion of the deposition process of the second layer, the wafer W is output using the arm mechanism 16 in the common transfer chamber 3 held in a vacuum state. Next, the wafer W is carried into the heat treatment apparatus 10 which has been previously vacuumed via the open gate valve G7. Here, first, the wafer W including the first and second tantalum oxide layers is reformed at a low temperature (about 450 ° C.) under an ultraviolet or ozone atmosphere, and subsequently heated up to a crystallization temperature of tantalum oxide or higher. , The temperature is lowered within 60 sec. As a result, the first and second tantalum oxide layers are crystallized in succession of performing the modification process of the second tantalum oxide layer. After completion of the crystallization step, the processed wafer W is taken out into the common transfer chamber 3 and accommodated in the cassette C in the second cassette chamber 14B.

Next, each process will be described with reference to FIGS. 2A to 2D.

First, as shown in FIG. 2A, the first tantalum oxide layer 20 is formed as a metal oxide film on the wafer W in the first CVD apparatus 4 to have a predetermined thickness. The source gas at this time is supplied by bubbling Ta (OC ₂ H ₅ ) _5, which is a liquid metal alkoxide, with He gas. At the same time, an oxidizing gas such as O ₂ is supplied. The supply amount of the metal alkoxide also depends on the deposition rate, for example, about several mg / min.

The process pressure of this CVD is set to about 0.2 to 0.3 Torr, and the process temperature is set in the range of 250 to 450 캜, for example, 400 캜. For example, the first tantalum oxide layer 20 having a thickness t1 of about 3.5 to 5.0 nm is deposited. At the end of the deposition process of the first layer 20, the first layer 20 is in an amorphous state. In addition, since an organic substance is used as a raw material, mixing of organic impurities in the first layer 20 is unavoidable.

Next, the wafer W is loaded into the reforming apparatus 8 and the reformed treatment is performed on the first tantalum oxide layer 20. In this reforming process, as shown in FIG. 2B, for example, ozone is supplied as a processing gas for providing an active oxygen atom, and a large amount of ultraviolet light is irradiated from the ultraviolet irradiation means 18. Thus, ozone is excited by ultraviolet irradiation to generate a larger amount of active oxygen atoms. The active oxygen atom oxidizes the organic impurities in the first tantalum oxide layer 20 formed on the wafer surface, and simultaneously decomposes and decomposes C-C bonds of the organic impurities by the energy of ultraviolet rays. As a result, the organic impurities in the first tantalum oxide layer 20 can be almost completely removed.

In the modification treatment, the ultraviolet rays are irradiated with a large amount of ultraviolet rays mainly composed of 185 nm and 254 nm. The process pressure is in the range of about 1 to 600 Torr, and the process temperature is set to 600 ° C or lower which is the crystallization temperature of tantalum oxide, and is set at, for example, about 425 ° C in the range of 320 to 600 ° C. When the process temperature is less than 320 ° C., the dielectric breakdown voltage of the first tantalum oxide layer 20 is not sufficient, and when the temperature exceeds 600 ° C., crystallization of the first tantalum oxide layer 20 may start to perform sufficient modification. none. The modification time is also dependent on the film thickness, but preferably 10 minutes or more. When the thickness t1 of the first tantalum oxide layer 20 is thinner than 4.5 nm, the modification treatment may be performed by supplying only ozone without irradiating ultraviolet rays.

After completion of the reforming process, the wafer W is loaded into the second CVD apparatus 6, and the second tantalum oxide layer 22 is deposited on the first tantalum oxide layer 20 as shown in FIG. 2C. The deposition conditions of the second layer 22 such as the source gas, the flow rate, the process pressure, the process temperature, and the like are set to be exactly the same as the deposition conditions of the first layer 20. The film thickness t2 of the second layer 22 is also set to, for example, 3.5 to 5.0 nm in the same manner as t1. At the end of the deposition process of the second layer 22, the first and second tantalum oxide layers 20, 22 are in an amorphous state.

Next, the wafer W is carried into the heat treatment apparatus 10 and the following processing is performed. That is, as shown in Fig. 2D, ozone is supplied as an active oxygen atom, for example, and the process pressure is set within a range of about 1 to 600 Torr. The process temperature is also varied with the crystallization temperature of tantalum oxide interposed. The control of the temperature of the wafer W (hereinafter simply referred to as the temperature of the wafer W) including the first and second tantalum oxide layers 20 and 22 described below is performed by the controller 51 (see FIG. 7). This is performed by adjusting the input power to each lamp 50.

First, in order to perform the modification process of the second tantalum oxide layer 22, the temperature of the wafer W is lower than the crystallization temperature (700 ° C or higher) of the tantalum oxide, preferably higher than the upper limit (600 ° C) of the modification temperature. Set to a low first temperature. Subsequently, in order to perform the crystallization treatment of the first and second tantalum oxide layers 20 and 22, the temperature of the wafer W is rapidly raised to a second temperature higher than the crystallization temperature, and then immediately lower than 600 ° C. Cool to temperature. Here, the period maintained at the first temperature is made longer than the period above the crystallization temperature.

Thus, the second tantalum oxide layer 22, which is the uppermost metal oxide film, is modified while reaching the crystallization temperature. Further, when the temperature reaches 700 ° C. or more, all tantalum oxide layers, that is, the first and second tantalum oxide layers 20 and 22 are crystallized together. That is, the modification process of the upper tantalum oxide layer 22 and the crystallization process of the 1st and 2nd tantalum oxide layers 20 and 22 can be performed continuously in the same chamber.

3 is a graph showing a change in process temperature of the heat treatment apparatus 10. In FIG. 3, the horizontal axis represents time Ti (sec), and the vertical axis represents process temperature PT.

For example, the wafer W is brought into the processing chamber 34 while the temperature of the wafer W and the temperature in the processing chamber 34 (refer to FIG. 7) are all about 450 ° C. The reforming process is performed by maintaining this temperature state for a predetermined time, for example, about 2 minutes. Subsequently, the power supply to the lamp 50 is increased to rapidly increase the temperature of the wafer W, thereby raising the temperature to 700 ° C or higher, for example, 750 ° C. At this time, a temperature increase rate is 30-130 degreeC / sec, for example, 100 degreeC / sec. At this time, the modification process is performed on the second tantalum oxide layer 22 during the temperature increase period up to about 600 ° C. In the temperature range exceeding 700 ° C, crystallization treatment of the first and second tantalum oxide layers 20 and 22 is performed.

The width of about 100 degreeC exists in the upper limit 600 degreeC of the modification temperature of a tantalum oxide layer, and 700 degreeC of a crystallization temperature. This is because crystallization does not occur instantaneously at a certain temperature boundary, but gradually progresses with a constant temperature range. Therefore, the modification of the second tantalum oxide layer 22 is also performed between 600 and 700 ° C, and the crystallization of the first and second tantalum oxide layers 20 and 22 is also started gradually, and both treatments are performed simultaneously. Going on.

In this case, the time T1 of modification of the tantalum oxide layer 22 also depends on the thickness of this layer. For example, when the thickness is about 4.5 nm, the time T1 is set to about 120 sec. On the other hand, since crystallization phenomenon occurs almost instantaneously, the length of time T2 of temperature 700 degreeC or more may be set to about 60 sec, for example. The crystallization temperature is preferably in the range of 700 to 800 ° C. When this temperature is higher than 800 degreeC, the base of a tantalum oxide layer will oxidize more and an effective film thickness will increase easily. Further, a problem arises in that the thermal influence on the semiconductor device is large and the characteristics deteriorate. The wafer after the treatment is purged with N ₂ gas at the same time as the process chamber 34, and the temperature is lowered to about 425 ° C. and carried out after pressure adjustment.

In the above description, in the step shown in FIG. 2D, it is possible to process the ultraviolet light without using only ozone. However, similarly to the process shown in FIG. 2B, ultraviolet light (UV) may be irradiated to accelerate the modification treatment. When the ultraviolet (UV) irradiation is applied, the modification process of the second tantalum oxide layer 22 can be further promoted, so that the modification time T1 of FIG. 3 can be shortened. However, even in this case, the period maintained at the reforming temperature becomes longer than the period above the crystallization temperature.

The insulation property of the insulating film which consists of the 1st and 2nd tantalum oxide layers 20 and 22 produced by the method of this invention, and the insulating film which consists of the 1st and 2nd tantalum oxide layers produced by the conventional method was evaluated. Here, the conventional method is to perform each reforming process and each crystallization process completely independently.

This experimental result is shown in FIG. In FIG. 4, the horizontal axis represents effective film thickness ET, and the vertical axis represents insulation breakdown voltage BV. In Fig. 4, the straight line LA shows the properties of the insulating film produced by the conventional method, the straight line LB shows the properties of the insulating film produced by the method of the present invention performed only by ozone without ultraviolet rays, and the straight LC shows the characteristics of the ultraviolet light and ozone. The characteristic of the insulating film produced by the method of the present invention performed is shown.

As shown in Fig. 4, the insulating film of the method of the present invention has a slightly higher dielectric breakdown voltage characteristic than the insulating film of the conventional method. That is, the method of the present invention can exhibit better characteristics than the conventional method even if the number of processes is reduced by one compared to the conventional method. In addition, as shown by the straight line LC, the insulation breakdown voltage characteristic can be further improved by using both ozone and ultraviolet rays.

In the method shown in FIGS. 2A to 2D, the thicknesses of the tantalum oxide layers 20 and 22 are all set to the same film thickness of approximately 3.5 to 5.0 nm. However, as shown in Figs. 5A to 5D, the thickness t1 of the lower first tantalum oxide layer 20 is set slightly thicker, for example, about 5.5 to 6.0 nm, and conversely, the upper second tantalum oxide layer 22 is formed. May be set slightly thinner, for example, about 2.5 to 4.0 nm. In this case, since the modification of the second tantalum oxide layer 22 becomes slightly thinner, the modification can be carried out quickly. Therefore, in the step shown in FIG. It is also possible to modify the layer 22 sufficiently and in a short time. That is, the modification time T1 in FIG. 3 can be made shorter.

Although the case where the tantalum oxide layer has a two-layer structure has been described as an example, the tantalum oxide layer 24 may be a single-layer structure as shown in Figs. 6A and 6B. In this case, after depositing a tantalum oxide layer 24 having a predetermined thickness as shown in Fig. 6A, the process proceeds to a modification and crystallization step as shown in Fig. 6B. As described in FIG. 2D, the tantalum oxide layer 24 is modified and crystallized at almost the same time. Also in this case, depending on the thickness of the tantalum oxide layer 24, it is sufficient to select whether to perform the treatment using only ozone or to perform the treatment by adding ultraviolet irradiation to the ozone. Also in this case, compared with the conventional method, the number of steps can be reduced from three steps to two steps while maintaining the insulation breakdown voltage characteristic.

It is a schematic block diagram which shows the principal part of the cluster tool type film forming system which concerns on other Example of this invention.

The film forming system 1M shown in FIG. 10 differs from the film forming system 1 shown in FIG. 1 in that it does not include the reforming apparatus 8 but includes two heat treatment apparatuses 10. According to the film forming system 1M shown in Fig. 10, a thin metal oxide film having a two-layer structure can be formed by the following method in which the modification and crystallization treatments of the respective layers are successively performed.

First, the cassette C containing 25 unprocessed wafers W, for example, is mounted on a cassette stage (not shown) in the first cassette chamber 14A. Subsequently, the gate door G3 is closed to make this room an inert gas atmosphere of N ₂ gas, and the chamber 14 is evacuated.

Next, the gate valve G1 is opened, and the inside of the cassette chamber 14A is evacuated in advance to communicate with the inside of the common transfer chamber 3 made of an inert gas atmosphere. The wafer W is loaded from the cassette chamber 14A using the arm mechanism 16 in the common transfer chamber 3.

Next, the wafer W is loaded into one CVD apparatus 4 which is evacuated in advance through the gate valve G5. Here, for example, a tantalum oxide (Ta ₂ O ₅ ) layer is deposited as the first layer of the insulating thin film. After completion of the deposition process of the first layer, the wafer W is output using the arm mechanism 16 in the common transfer chamber 3 held in a vacuum state.

Next, the wafer W is loaded into one of the heat treatment apparatuses 10 which have been vacuumed in advance through the open gate valve G6. Here, first, the wafer W including the first tantalum oxide layer is modified at a low temperature (about 450 ° C.) under an ultraviolet or ozone atmosphere, and subsequently heated up to at least the crystallization temperature of tantalum oxide, and then within 60 sec. Lower the temperature. As a result, the first tantalum oxide layer is crystallized in succession of performing the modification process of the first tantalum oxide layer.

After the process in one heat processing apparatus 10 is complete | finished, it outputs using the arm mechanism 16 into the common conveyance chamber 3 hold | maintained in a vacuum state. Next, the wafer W is brought into the second CVD apparatus 6 previously held in a vacuum state through the open gate valve G8, where the film forming process in the first CVD apparatus 4 and The second tantalum oxide layer is deposited under the same conditions.

After completion of the deposition process of the second layer, the wafer W is taken out using the arm mechanism 16 in the common transfer chamber 3 held in a vacuum state. Next, the wafer W is carried into the other heat treatment apparatus 10 which has been previously vacuumed via the gate valve G7 which opened. Here, first, the wafer W including the first and second tantalum oxide layers is reformed at a low temperature (about 450 ° C.) under an ultraviolet or ozone atmosphere, and subsequently heated up to at least the crystallization temperature of tantalum oxide. The temperature is lowered within 60 sec. As a result, the second tantalum oxide layer is crystallized subsequent to performing the modification process of the second tantalum oxide layer. After the process in the other heat processing apparatus 10 is complete | finished, the processed wafer W is taken out in the common conveyance chamber 3, and is accommodated in the cassette C in the 2nd cassette chamber 14B.

In addition, according to the film forming system 1M shown in FIG. 10, as described with reference to the film forming system 1 shown in FIG. 1, the modification of the first tantalum oxide layer in one heat treatment apparatus 10 is performed. It is also possible to set the program to execute only the processing and to perform the modification process of the second tantalum oxide layer and the crystallization process of the first and second tantalum oxide layers in the other heat treatment apparatus 10.

11 is a schematic configuration diagram showing a main part of a heat treatment apparatus according to still another embodiment of the present invention. The structure shown in FIG. 11 can be used also as a main part of any one of the apparatus 8 and the heat treatment apparatus 10 of the film forming system 1 shown in FIG. 1 and FIG.

The heat treatment apparatus 102 has the process chamber 104 shape | molded in the substantially rectangular box shape, for example by the aluminum whose surface was covered with the alumite as shown. A plurality of exhaust ports 112 are disposed at the periphery of the bottom portion 106 of the processing chamber 104. The exhaust port 11 is connected to a vacuum exhaust mechanism 110 provided with a vacuum pump 108, so that the inside of the processing chamber can be evacuated.

A port 172 is formed on the side wall of the processing chamber 104, and a load lock chamber 174 configured to enable vacuum evacuation is connected via the gate valve 176. The semiconductor wafer W is carried in and out of the process chamber 104 via the load lock chamber 174. In addition, a supply mechanism (not shown) for purging N ₂ gas is connected to the processing chamber 2 and the load lock chamber 174.

In the processing chamber 104, a non-conductive material such as a disc-shaped mounting table 114 made of alumina is disposed. The semiconductor wafer W can be mounted on the mounting table 114 as an object to be processed. The lower center part of the mounting table 114 is supported and fixed to the front end of the hollow rotating shaft 116 provided through the process chamber bottom part 106 up and down. A magnetic fluid seal 118 is disposed in the penetrating portion of the rotary shaft 116 with the processing chamber bottom 106. The rotating shaft 116 is hermetically and rotatably supported by the sealing member 118, so that the mounting table 114 can rotate as needed. In addition, the rotating shaft 116 is rotated by a driving force from a rotating motor (not shown) or the like.

In the mounting table 114, for example, a resistive heating element 120 made of carbon coated with SiC is embedded, and the mounted semiconductor wafer W can be heated to a desired temperature. On the mounting table 114, a thin ceramic electrostatic chuck 124 in which electrodes 122 such as steel sheets are embedded is disposed. The wafer W is adsorbed and held on this upper surface by the Coulomb force generated by the electrostatic chuck 124.

At a predetermined position of the periphery of the mounting table 114, the plurality of holes 126 are formed to penetrate in the up and down direction, and the lifter pin 128 is disposed in the hole 126 so as to be elevated. The lifter pin 128 is driven up and down integrally by the pin lifting rod 130 which is movable up and down through the process chamber bottom 106. A metallic telescopic bellows 132 is disposed in the penetrating portion of the rod 130 to allow the rod 130 to move up and down while maintaining airtightness. During loading and unloading of the wafer W, the wafer W is lifted by a lifting mechanism (not shown) via the lifter pin 128. Generally, three lifter pins 128 are arranged corresponding to the wafer peripheral portion.

Further, a shower head 134 made of a heat-resistant material, for example, quartz, which is transparent to ultraviolet rays or infrared rays, is disposed in the ceiling of the processing chamber 104. Process gas is discharged from the showerhead 134 toward the processing space PF.

The showerhead 134 has the same lattice shape as the showerhead 56 shown in FIG. 8. That is, the showerhead 134 has a ring-shaped pipe 136 larger than the diameter of the wafer W connected to the line pipe 142, and an inner pipe 138 connected to the inside and woven in a lattice shape. . In the inner pipe 138, a plurality of gas injection holes 61 (see Fig. 8) are formed at the same pitch at the lower side. The inner diameters of the ring pipe 136 and the inner pipe 138 are set to about 16 mm and 4.35 mm, respectively, and the diameter of the gas injection hole 61 is set to about 0.3 to 0.5 mm.

It is preferable to set the projection area of the inner pipe 138 to the wafer W on the mounting table 114 to be smaller than 20% of the area of the wafer surface. Thereby, the light beam mentioned later is easily irradiated to the wafer surface to the space part between the gratings of the inner pipe 138 directly. However, as long as the showerhead 134 is transparent to ultraviolet rays or infrared rays, it is not limited to the structure of the figure.

The line pipe 142, which introduces the process gas into the showerhead 134, is hermetically penetrated through the process chamber sidewall and is led outward. The line pipe 142 is connected to the gas source 144 via a mass flow controller (not shown). Process gas, such as ozone, is introduced from the gas source 144 into the showerhead 134 via the line pipe 142.

In the ceiling of the processing chamber 104, a rectangular opening 146 set larger than the wafer diameter is formed. In this opening, a rectangular transmission window 148 formed of a material transparent to ultraviolet rays or infrared rays, such as quartz, is hermetically sealed by a fixing frame 152 through a sealing member 150 such as an O-ring between the ceiling and the ceiling. Is fitted. The transmission window 148 is set to a thickness of, for example, about 20 mm so as to withstand atmospheric pressure.

Above the transmission window 148, a light emitting mechanism 156 for emitting light 154 toward the inside of the processing chamber 104 is disposed. Active oxygen atoms are generated by irradiating light 154 to ozone, which is a processing gas.

Specifically, the light emitting mechanism 156 includes a substantially spherical mercury-containing lamp 158 in which mercury is encapsulated mainly for generating ultraviolet (UV), and a substantially spherical spherical shape for generating infrared (IR). Has an infrared lamp 160. To the mercury encapsulation lamp 158, for example, a microwave generating mechanism 162 for generating 2.45 GHz microwaves is connected via a waveguide 164. In addition, a power source 166 is connected to the infrared lamp 160 via a lead 168.

The infrared lamp 160 is used to raise the temperature of the metal oxide film which is a film to be processed, as will be described later. Therefore, the power supply 166 of the infrared lamp 160 and the power supply 120A of the resistance heating element 120 on the mounting table 114 have a common temperature controller 51 (controller 51 shown in FIG. 7). The same role as).

An approximately dome shaped reflector 170 is disposed to cover the upper side of each lamp 158, 160 and reflect the light beam 154 made of a mixed light of ultraviolet (UV) and infrared (IR) toward the processing chamber 104. . The reflector 170 is configured by, for example, molding aluminum into a dome shape, and the curvature is set such that the reflected light of the light beam 154 is reflected approximately evenly on the surface of the mounting table 114.

Next, a heat treatment method performed using the apparatus shown in FIG. 11 will be described.

First, a semiconductor wafer W on which a metal oxide film such as Ta ₂ O ₅ is disposed as an insulating film is introduced into the processing chamber 104 held in a vacuum state from the load lock chamber 174 via the port 172. Next, the wafer W is mounted on the mounting table 114 and adsorbed and held by the Coulomb force of the electrostatic chuck 124.

The resistive heating element 120 maintains the wafer W at a predetermined process temperature. The inside of the processing chamber 104 is maintained at a predetermined process pressure by supplying a gas containing ozone as the processing gas from the shower head 134 to the processing space PF while evacuating the inside of the processing chamber 104. In this state, the modification treatment or the modification and crystallization treatment is started as described with reference to the film formation system of FIG. 1.

At the time of processing, a microwave of 2.45 GHz is generated from the microwave generating mechanism 162 of the light emitting mechanism 156 and irradiated to the mercury-containing lamp 158 via the waveguide 164. The irradiation of microwaves emits a large amount of ultraviolet (UV) light from the mercury-encapsulation lamp 158. At the same time, a large amount of infrared rays IR are emitted from the infrared lamp 160 by the power from the infrared power source 166. The light ray 154 including ultraviolet (UV) light and infrared light (IR) light is directly or reflected by the dome-shaped reflector 170 and then transmitted through the quartz transmission window 148 and maintained at a predetermined vacuum pressure. Enter 104. The light ray 154 passes through the shower head 134 made of quartz and is injected into the processing gas whose main component is ozone in the processing space PF.

Ozone is excited by irradiation with ultraviolet (UV) light to generate a large amount of active oxygen atoms. The active oxygen atom acts on the metal oxide film to dissociate organic impurities such as C-C bonds and hydrocarbons contained therein to perform the modification. At this time, since the surface of the wafer W is particularly heated by the infrared rays IR, thermal vibration between atoms in the crystal lattice of the metal oxide film vibrates more severely. For this reason, desorption of organic impurities when an active oxygen atom acts can be promoted.

Since the processing chamber 104 is maintained in a vacuum state or a reduced pressure state, the probability of generated active oxygen atoms colliding with other gas atoms or gas molecules becomes extremely small. In addition, since the absorption of the light rays 154 by gas molecules is small, the density of the active oxygen atoms can be improved by that amount, and the processing can be performed quickly. By this treatment, it is possible to rapidly and significantly improve the insulation of the metal oxide film.

The dome-shaped reflecting mirror 170 of the light emitting mechanism 156 is set to an appropriate curvature such that the reflected light therefrom is distributed approximately evenly on the surface of the mounting table 114. For this reason, the generated ultraviolet (UV) or infrared (IR) can be used for generation of active oxygen atoms without waste.

During the above heat treatment, the mounting table 114 supported by the rotating shaft 116 rotates the wafer W mounted thereon integrally. For this reason, the processing nonuniformity on a wafer surface can be eliminated and the whole surface of a metal oxide film can be processed substantially evenly.

The process pressure is set in the range of 1 to 600 Torr, for example, about 30 Torr. At a pressure outside this range, the progress of the process is delayed or insufficient, and the dielectric breakdown voltage of the metal oxide film decreases. In addition, the process temperature is set in the range of 320-600 degreeC, for example about 425 degreeC in the case of a reforming process, and makes it into the range of 700-800 degreeC, for example, 750 degreeC in the case of crystallization process.

Process gas, such as ozone, introduced into the shower head 134 first enters along the ring pipe 136 and flows into each inner pipe 138. Next, the processing gas is supplied into the processing chamber 104 from the plurality of injection holes 61 provided in the inner pipe 138.

For this reason, a process gas can be supplied uniformly with respect to a wafer surface.

Between the lattice inner pipes 138 of the shower head 134 is formed as an opening, many ultraviolet (UV) rays or infrared rays (IR) pass through the opening. Therefore, many ultraviolet rays (UV) or infrared rays (IR) are irradiated directly on the wafer surface without interfering with ozone or the like in the shower head 134. For this reason, the amount of active species on the wafer surface increases by that much, and the process can be performed more efficiently.

Since the mercury encapsulation lamp 158 can apply a large amount of power, it can emit a large amount of ultraviolet light mainly composed of wavelengths 185 nm and 254 nm, which can contribute to the activation of the gas. Further, instead of the lamp 158, by using an excimer lamp that emits a large amount of ultraviolet light having a wavelength of 180 nm or less, which can further contribute to the activation of the gas, it is possible to further accelerate the processing. As the ozone gas was added to in the process gas, O ₂ it is possible to use a gas, N ₂ O gas, or the like.

The conventional method which carried out the modification only by the ultraviolet-ray and the method of this invention which performed the modification using the ultraviolet-ray and infrared ray were compared. Reforming conditions at this time, the temperature is 425 ℃, pressure flow rate of 30Torr, O ₂ is the concentration of 10slm, O ₃ is 130g / ㎥, processing time was set to 30sec.

This experimental result is shown in FIG. In FIG. 12, the horizontal axis represents effective film thickness ET, and the vertical axis represents insulation breakdown voltage BV. In Fig. 12, line L11 represents the result of the conventional method, and line L12 represents the result of the method of the present invention. As is apparent from this graph, the breakdown voltage of the film is significantly higher in the case of the method of the present invention than in the conventional method. In particular, when the film thickness is 10 nm or less, the difference between them is remarkable, and the method of the present invention exhibits particularly good characteristics.

In the embodiment shown in FIG. 11, two different light sources, the mercury-encapsulation lamp 158 and the infrared lamp 160, are used as the light emitting mechanism 156. Instead, a lamp including at least wavelengths of an ultraviolet region and an infrared region may be used as one light source, for example, an electrodeless microwave light emitting lamp. A light emitting lamp of an electrodeless microwave system emits light (including a visible light region) in both bands of an ultraviolet region and an infrared region with one lamp. For this reason, the number of lamps used can be reduced, and operation cost and initial cost can be reduced.

In addition, in the Example shown in FIG. 11, the large-capacity mercury sealing lamp 158 and the ultraviolet lamp 160 are fixed and used. These lamps may be used to scan the semiconductor wafer W with the light rays 154 generated from the respective lamps using medium or small capacitances.

Fig. 13 is a schematic block diagram showing a main part of a heat treatment apparatus according to another embodiment of the present invention based on this aspect. 14 is a schematic plan view of the apparatus shown in FIG. 13.

As shown in FIG. 13, as the light emitting mechanism 156, an elongated rod-shaped mercury-sealing lamp 158A and an elongated rod-shaped infrared lamp 160A are used. On the back side of each of the lamps 158A and 160A, reflectors 170A and 170B having a substantially arcuate cross section are arranged, and ultraviolet (UV) or infrared (IR) are irradiated with high directivity downward.

The lamps 158A and 160A are accommodated in the frame 178 which is open downward. The frame 178 is attached to the scanning mechanism 192 and can move the upper part of the process chamber 104 in the horizontal direction as shown in FIG. Specifically, the scanning mechanism 192 consists of the guide rail 194 provided in the upper side of the process chamber 104, and the drive rail 196 which consists of ball screws provided on the other side. A frame 178 is disposed across these rails 194, 196 so as to be movable along the rails. When the drive motor 198 composed of a step motor and the like provided at one end of the drive rail 196 is driven to reverse rotation, the lamps 158A and 160A are integrally moved along the rail.

As described above, by the scanning mechanism 192, the light ray 154 composed of ultraviolet (UV) light from the mercury-encapsulation lamp 158A and infrared light (IR) from the infrared lamp 160A is formed on the surface of the wafer W. As shown in FIG. Inject As a result, as described with reference to FIG. 11, the metal oxide film on the surface of the wafer W can be efficiently and quickly processed by the light rays 154 including both ultraviolet (UV) and infrared (IR) light. In particular, in the case of the present embodiment, the wafer surface can be irradiated with the light beam 154 to increase the in-plane uniformity of the processing.

The light from each of the lamps 158A and 160A, although slightly, cannot be diffused laterally, so that the amount of light at the wafer end slightly decreases with respect to the center of the wafer in the scanning direction. Thus, as shown in Fig. 15, the scanning speed is set at a slightly lower speed at the scanning start end side and the scanning end end side. As a result, the amount of irradiation light at the scanning start end side and the scanning end end side is increased to compensate for the decrease by the degree to which the speed is lowered, and the in-plane uniformity of the processing can be further improved.

In addition, in this embodiment, since only two lamps 158A and 160A having a small capacity are used, a large number of lamps are provided on the upper side of the ceiling of the processing chamber 104, or as shown in FIG. As compared with the case of using a very powerful lamp as described above, the installation cost can be greatly reduced.

In the embodiment shown in FIG. 13, the frame 178 including two lamps 158A and 160A is moved. Instead, scanning may be performed by moving a reflection mirror that reflects light rays emitted from both lamps in the direction of the wafer W. FIG.

Fig. 16 is a schematic structural diagram showing a main part of a heat treatment apparatus according to another embodiment of the present invention based on this aspect.

In this embodiment, the frame 178 having the mercury encapsulation lamp 158A, the infrared lamp 160A, and the reflecting mirrors 170A, 170B is disposed and fixed in a horizontal direction on one side above the ceiling of the processing chamber 104. To face this, an elongated reflecting mirror 180 inclined at approximately 45 ° with respect to the horizontal direction is disposed between the guide rail 194 (see FIG. 14) and the drive rail 196 of the scanning mechanism 192. do. As a result, the reflective mirror 180 can move along the rails 194 and 196.

The light rays 154 composed of ultraviolet (UV) and infrared (IR) radiated horizontally from the two lamps 158A and 160A are reflected downward by the moving reflection mirror 180 to reflect the wafer W. Inject the surface. Therefore, as in the case shown in FIG. 13 above, the process can be executed quickly and efficiently. In addition, since the wafer surface is scanned by the light rays 154, it becomes possible to increase the in-plane uniformity of the processing.

In addition, the embodiment shown in FIG. 16 moves the reflection mirror 180 of a relatively light object compared with the embodiment shown in FIG. 13 which moves heavy objects, such as lamp 158A, 160A, the frame 178, and the like. For this reason, according to the embodiment shown in FIG. 16, not only operability is improved but also the intensity | strength of the injection mechanism 192, etc. can be reduced.

In the case of this embodiment, the amount of diffused light increases as the reflection mirror 180 moves away from the light source lamps 158A, 160A. For this reason, as shown in the scanning speed graph written in the upper part of FIG. 16, as the reflection mirror 180 moves away from the light source lamps 158A and 160A, it sets so that the movement speed may fall. As a result, the amount of light can be compensated for as the reflection mirror 180 is farther away, and the in-plane uniformity of the process can be further improved.

In the embodiment shown in Fig. 16, the light beam is driven by scanning by moving the reflection mirror 180 in the horizontal direction. Alternatively, the light beam may be scanned by rotating the mirror.

Fig. 17 is a schematic structural diagram showing a main part of a heat treatment apparatus according to another embodiment of the present invention based on this aspect.

In this embodiment, instead of the scanning mechanism 192 shown in FIG. 16, the reflection mirror mechanism 182 is disposed in the center of the ceiling of the processing chamber 104. Specifically, the mirror mechanism 182 is composed of an elongated reflective mirror 180 and a rotation shaft 184 that fixes and integrally rotates the reflective mirror 180. At one end of the rotating shaft 184, for example, a step motor (not shown) is disposed, and the reflection mirror 180 is rotated forward and backward within a predetermined angle range. The frame 178 having the mercury-encapsulating lamp 158A, the infrared lamp 160A, and both reflecting mirrors 170A, 170B is disposed and fixed in a horizontal direction on one side above the ceiling of the processing chamber 104.

Light rays 154 made of ultraviolet (UV) light and infrared light (IR) emitted from two lamps 158A and 160A in the horizontal direction are reflected by the reflection mirror 180 to scan the surface of the wafer W. . Therefore, also in this case, the process can be executed quickly and efficiently as in the case shown in FIG. In addition, since the wafer surface is irradiated with the light beam 154, the in-plane uniformity of the processing can be increased.

In addition, in this embodiment, since a large-scale injection mechanism as shown in FIG. 13 or FIG. 16 is unnecessary, the apparatus can be simplified and the cost can be reduced. In addition, in this embodiment, the rotation speed of the reflection mirror 180 is the fastest when the reflected light is reflected directly below. As the angle of rotation of the reflective mirror 180 in the left and right directions gradually increases, the optical path length becomes longer and the amount of diffused light gradually increases, so that the rotation speed is made low. As a result, the amount of light on the wafer surface reduced by diffusion can be compensated, and the in-plane uniformity of the modification process can be further improved.

18 is a schematic configuration diagram showing a main part of a heat treatment apparatus according to still another embodiment of the present invention. 19 is a schematic plan view of the apparatus shown in FIG. 18.

In this embodiment, the transmission window is not disposed on the ceiling of the processing chamber 104, and the entire ceiling is made of, for example, an aluminum plate. An opening 186 is formed on one side of the processing chamber 104, and a thin elongated transmission window 190 made of, for example, quartz and the same material as the transmission window 148 in FIG. 11 is disposed through the sealing member 188. do. On the outside of the transmission window 190, a frame 178 including two lamps 158A and 160A and two reflecting mirrors 170A and 170B similar to those shown in Fig. 17 and the like is disposed and fixed in the horizontal direction. In this case, the light rays 154 emitted from both lamps 158A and 160A pass through the processing space PF in the horizontal direction.

Also in this case, since the light ray 154 introduced into the processing space PF from the horizontal direction excites a processing gas containing ozone, it is possible to efficiently process the metal oxide film on the wafer surface. In this embodiment, as a result of providing both lamps 158A and 160A on the side of the processing chamber 104, the light beam 154 does not pass through the portion of the showerhead 134 provided in the ceiling. For this reason, the absorption amount in the middle of the irradiated light ray 154 reduces, and many light rays can be thrown into the processing space PF by that much. Therefore, the processing can be performed quickly as the amount of light of the light ray 154 to be injected into the processing space PF is large.

In addition, the amount of light in a portion close to both lamps 158A and 160A increases somewhat compared to the far portion where the amount of light decreases due to diffusion. However, since the wafer W is rotated during the treatment by the rotation of the mounting table 114, the in-plane uniformity of the treatment can be maintained high.

In addition, in the Example shown to FIGS. 13-19, the heating lamp 50 as shown in FIG. 7 and FIG. 9 is used instead of the resistance heating body 120 as a heater of the mounting table 114 side. It is possible. In particular, when using these heat treatment apparatuses as a device for reforming and crystallization treatment, it is preferable to use the heating lamp 50 rather than the resistance heating element 120 from the viewpoint of the heating power.

13 to 18 can be applied not only to the use of the ultraviolet lamp 158A and the infrared lamp 160A, but also to the use of only the ultraviolet lamp 158A. The shape of each lamp is not limited to a straight one, but may be used, for example, bent in a U shape.

In each of the above embodiments, a case where a tantalum oxide layer is formed as a metal oxide film has been described as an example. However, the present invention is not limited to a tantalum oxide film, but the titanium oxide film, zirconium oxide film, barium oxide film, and strontium oxide film are described. The present invention can also be applied to forming metal oxide films such as metal oxide films, titanium nitride and tungsten nitride, or metal films such as Ti, Pt, Ru, and Ir. As the processing gas, it is preferable to use ozone or oxygen when treating a metal oxide film or a metal nitride film, and to use an inert gas such as nitrogen, hydrogen, Ne, He, or Ar instead of ozone which is a corrosive gas when treating a metal film. 22.

As described above, according to the sheet type heat treatment apparatus and method for carrying out the modification and crystallization of the present invention, throughput can be improved while equipment cost and production cost can be reduced.

In the case where the deposited metal oxide film has a single layer structure, when the crystallization step is performed, the reforming process and the crystallization process are continuously performed in the same chamber, whereby the total number of steps can be reduced while maintaining high insulation characteristics.

In the case where the deposited metal oxide film has a two-layer structure, the uppermost metal oxide film is reformed and the crystallization of the metal oxide film of the first and second layers as a whole is continuously performed in the same chamber, thereby maintaining the high insulation characteristics. Process water can be reduced.

Claims (4)

A sheet type heat treatment apparatus for performing a modification treatment for removing organic impurities contained in a thin film disposed on a substrate to be processed and a crystallization treatment for crystallizing the thin film, wherein the thin film is a group consisting of metal oxides, metal nitrides, and metals. In the single wafer type heat treatment apparatus, which comprises a material selected from With a confidential treatment chamber, A mounting table for mounting the target substrate disposed in the processing chamber; An exhaust mechanism for exhausting the processing chamber, A supply mechanism for supplying a processing gas containing oxygen atoms into the processing chamber; A heating mechanism for heating the thin film in a state in which the target substrate is mounted on the mounting target; A control unit for controlling the heating mechanism; The control unit heats the thin film to a first temperature lower than the crystallization temperature of the material over a first period of time to perform the reforming treatment, and subsequently causes the thin film to be higher than the crystallization temperature to perform the crystallization treatment. The heating mechanism is controlled to raise to a second temperature and cool to a temperature lower than the crystallization temperature, wherein the first period is longer than a second period when the thin film is above the crystallization temperature. Single sheet heat treatment device. A film forming system for forming a crystallized thin film on a substrate to be processed, wherein the thin film is made of a material selected from the group consisting of metal oxides, metal nitrides, and metals. Confidential common return room, A transport mechanism disposed in the common transport chamber for transporting the substrate to be processed, A sheet-fed CVD apparatus connected to said common transfer chamber via a gate valve for depositing an amorphous thin film on said substrate to be processed by CVD; A sheet type heat treatment apparatus connected to the common transfer chamber via a gate valve to perform a reforming process for removing organic impurities contained in the thin film and a crystallization process for crystallizing the thin film, The heat treatment apparatus, With a confidential treatment chamber, A mounting table for mounting the target substrate disposed in the processing chamber; An exhaust mechanism for exhausting the processing chamber, A supply mechanism for supplying a processing gas containing oxygen atoms into the processing chamber; A heating mechanism for heating the thin film in a state where the substrate to be processed is mounted on the mounting object; And a control unit for controlling the heating mechanism, the control unit heating the thin film to a first temperature lower than the crystallization temperature of the material over a first period in order to perform the modification treatment, and subsequently performing the crystallization treatment. Controlling the heating mechanism to raise the thin film to a second temperature higher than the crystallization temperature and to cool to a temperature lower than the crystallization temperature to perform the first period, wherein the first period of time is characterized in that the thin film is above the crystallization temperature. Longer than 2nd period Membrane forming system. A method of forming a crystallized thin film on a substrate to be processed, wherein the thin film is made of a material selected from the group consisting of metal oxides, metal nitrides, and metals. Depositing an amorphous thin film on the substrate to be treated by CVD; Mounting the to-be-processed substrate on which the thin film is disposed on a mounting target in an airtight processing chamber; The first temperature lowering the crystallization temperature of the material over the first period of time while supplying a processing gas containing oxygen atoms into the processing chamber while evacuating the processing chamber, and at the same time. Performing a reforming treatment to remove organic impurities contained in the thin film by heating with; Following the reforming process, the thin film of the substrate to be mounted is heated to a second temperature higher than the crystallization temperature and cooled to a temperature lower than the crystallization temperature, thereby performing a crystallization process of crystallizing the thin film. Steps, The first period is longer than a second period during which the thin film is above the crystallization temperature. A method of forming a crystallized thin film on a substrate to be processed. A method of forming a crystallized thin film on a substrate to be processed, wherein the thin film includes first and second layers made of a material selected from the group consisting of metal oxides, metal nitrides, and metals. Depositing an amorphous first layer by CVD on the substrate; Performing a reforming treatment to remove organic impurities contained in the first layer by heating the first layer to a temperature lower than the crystallization temperature of the material in an atmosphere containing active oxygen atoms; Depositing a second layer in an amorphous state by CVD on the first layer subjected to the modification treatment; Mounting the to-be-processed substrate on which the second layer is disposed on a mounting target in an airtight processing chamber; While exhausting the inside of the processing chamber, while supplying a processing gas containing oxygen atoms into the processing chamber, the two layers of the substrate to be mounted are subjected to a first temperature lower than the crystallization temperature over a first period. Performing a reforming treatment to remove organic impurities contained in the second layer by heating; Following the modification treatment of the second layer, the first and second layers of the substrate to be mounted are heated to a second temperature higher than the crystallization temperature and cooled to a temperature lower than the crystallization temperature, Performing a crystallization process to crystallize the first and second layers, The first period is longer than a second period in which the first and second layers are above the crystallization temperature. A method of forming a crystallized thin film on a substrate to be processed.