JP2007059735A - Method for manufacturing semiconductor device, and substrate processing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a semiconductor device which is excellent in step coating and adhesion with a rapid film formation rate, high productivity, and less plasma damage; and also to provide a substrate processing apparatus. <P>SOLUTION: The semiconductor device manufacturing method is provided by a so-called CVD (Chemical Vapor Deposition) method or an ALD (Atomic Layer Chemical Vapor Deposition) method, where a process for depositing a thin film on a substrate by supplying a reactive gas excited with plasma is performed by following a process for supplying a raw material gas so as to be adopted as one step and the step is repeated. A plasma generator is arranged at a position facing a substrate where the film is deposited, being the same as the position of a supply port for directly supplying the raw material gas and the reactive gas to the substrate where the film is deposited, or being closer to the substrate with the deposited film than the supply port. The plasma is used, which is generated by high frequency wave applied to a part among at least not less than one group of opposing electrodes. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a semiconductor device manufacturing method and a substrate processing apparatus for forming a thin film on a substrate.

In order to ensure the accumulated charge capacity of a DRAM capacitor with miniaturization, research on increasing the dielectric constant of the capacitor insulating film and metallization of the lower electrode or the upper electrode has been active.
These materials include Al ₂ O ₃ , ZrO ₂ , HfO ₂ , Y ₂ O ₃ , La ₂ O ₃ , STO (SrTiO ₃ ), which have a high dielectric constant,
Ta ₂ O ₅ , BST ((Ba, Sr) TiO ₃ ), PZT ((Pb, Zr) TiO ₃ ), etc. are used as capacitive insulating films, Ti, Hf
, Zr, Al, Ru, Pt, Ir metals, oxides such as SRO (SrRuO3), RuO2, or TiN, HfN, ZrN
Such nitrides are candidates for electrodes.
The electrode shape is mainly a cylinder type with a high aspect ratio. In some cases, all the films including TiN, TaN, etc., which are barrier metal films, need to have excellent step coverage.
The film formation method has shifted from the conventional sputtering method to the CVD method with excellent step coverage, and the reaction between the organometallic liquid raw material and oxygen-containing gas, hydrogen-containing gas or nitrogen-containing gas is used. .

In order to improve the step coverage in the CVD method, lowering the temperature is inevitable. As the temperature is lowered, a large amount of carbon and hydrogen in the organic liquid raw material remain in the film as impurities, which degrades the electrical characteristics.
Further, impurities may be desorbed by heat treatment in a later process, and the film may peel off. Furthermore, there are reports that the incubation time increases for some organic liquid raw materials, resulting in poor productivity. Then, CVD which repeats film formation modification of several to several tens of kilometers and film quality by plasma under the CVD conditions that improve the step coverage is being studied.
In addition, a method of forming a film by supplying hydrogen or ammonia excited by plasma after supplying and adsorbing only the vaporized gas of the organic liquid material to the substrate, so-called ALD (Atomic Laye).
r Chemical Vapor Deposition) method is also used. As these plasma sources, parallel plate type capacitively coupled discharge plasma (CC) is used to uniformly supply plasma gas to the wafer.
P) is used. However, in this method, an electric field is applied between the deposition target substrate and the plasma source, and ions or electrons existing in the plasma directly collide with the deposition target substrate, so that the formation is attempted. There was a problem of damaging the base of the thin film.

Accordingly, an object of the present invention is to form a film using a plasma such as a CVD method in which film formation is improved by several to several tens of thousands under CVD conditions with good step coverage and plasma quality improvement by plasma, and an ALD method using plasma. Another object of the present invention is to provide a semiconductor device manufacturing method and a substrate processing apparatus that are excellent in step coverage and adhesion, have a high film formation rate, high productivity, and low plasma damage.

The first feature of the present invention is that, following the step of supplying the raw material gas, a step of supplying a reactive gas excited by plasma to form a thin film on the substrate is repeated as one step. The so-called CVD (Chemical Vapor Deposition) method or ALD (Atomic Layer)
In the method of manufacturing a semiconductor device by the Chemical Vapor Deposition method, the plasma generation unit faces the deposition target substrate and is at the same position as a direct supply port of the source gas and the reaction gas to the deposition target substrate, or A method for manufacturing a semiconductor device, comprising: using plasma generated by a high frequency applied between at least one pair of opposed electrodes disposed closer to a deposition target substrate than the supply port. is there.

The second feature of the present invention is that, in the first feature, the source gas is Al, Si, Ti,
V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Sr, Y, Zr, Nb, Mo, Ru, Rh, Pd, Ag, In, I,
Ba, La, Hf, Ta, W, Re, Os, Ir, Pt, Au, Pb, Bi, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy,
At least one kind of gas containing at least one element selected from the group consisting of Ho, Er, Tm, Yb, Lu, and the reaction gas is H, He, N, O, F, Ne, Cl , Ar, Kr, Xe, which is at least one kind of gas containing at least one element selected from the group consisting of Ar, Kr, and Xe.

The third feature of the present invention is that, following the step of supplying the source gas, a step of supplying a reactive gas excited by plasma to form a thin film on the substrate is repeated as one step. The so-called CVD (Chemical Vapor Deposition) method or ALD (Atomic Layer)
In the substrate processing apparatus by the Chemical Vapor Deposition) method, the plasma generator is
Opposite to the film formation substrate, it is disposed at the same position as the direct supply port of the source gas and the reaction gas to the film formation substrate, or at a position closer to the film formation substrate than the supply port, and faces the film formation substrate. In the substrate processing apparatus, plasma generated by a high frequency applied between at least one set of electrodes is used.

A fourth feature of the present invention is that, in the third feature, the source gas is Al, Si, Ti.
, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Sr, Y, Zr, Nb, Mo, Ru, Rh, Pd, Ag, In,
I, Ba, La, Hf, Ta, W, Re, Os, Ir, Pt, Au, Pb, Bi, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy
, Ho, Er, Tm, Yb, Lu, and at least one kind of gas containing at least one element selected from the group consisting of H, He, N, O, F, Ne, Cl, Ar, Kr, Xe
The substrate processing apparatus is characterized in that it is at least one kind of gas containing at least one element selected from the group consisting of:

ADVANTAGE OF THE INVENTION According to this invention, it can provide the manufacturing method of the semiconductor device which is excellent in level | step difference covering property and adhesiveness, is highly productive, and does not have a plasma damage.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

First, the configuration concept of a substrate processing apparatus in which the present invention is implemented will be described with reference to FIGS.
FIG. 1 is a cross-sectional view showing a configuration concept of an example of a single wafer processing apparatus in which a direct plasma unit which is a substrate processing apparatus according to an embodiment of the present invention is incorporated. FIG. 2 is a plan view showing a configuration of an example of a direct plasma unit of the substrate processing apparatus according to the embodiment of the present invention.

As shown in FIG. 1, a reaction chamber 1 for film formation is evacuated by a vacuum pump (not shown) connected to an exhaust port 10 and kept in a vacuum. The film formation surface is arranged to face the source gas supply port 4 and the reaction gas supply port 3. As shown in FIG. 2, the counter electrode unit 5 for generating plasma is configured as a unit in which a pair of electrodes 6 and 7 are alternately arranged to face each other. That is, both the electrodes 6 and 7 are configured in a comb-teeth shape, and are arranged so that portions corresponding to the respective comb teeth are alternately adjacent (opposed). In other words, one comb tooth of the other electrode is inserted between the comb teeth of one electrode. The electrodes 6 and 7 are arranged on the same plane. The counter electrode unit 5 faces the substrate 2 and is disposed at the same position as the shower hole 8 which is a direct supply port of the source gas and the reaction gas to the substrate.

Next, an ALD film forming method using this apparatus will be described.
First, (1) a gas gas containing a source gas is supplied to the substrate 2 through the supply port 4, and the source gas is adsorbed on the substrate surface. Subsequently, (2) an inert gas such as Ar, He, or N _{2 is} introduced from the supply port 4 to desorb / exhaust excess source gas remaining in the reaction chamber and gas adsorbed on the inner surface of the reaction furnace. (3) A reactive gas is supplied from the supply port 3 and a high frequency is applied between the counter electrodes 6 and 7 to generate plasma. Then, plasma is generated at a position 18 shown in FIG.
Plasma is also generated in the shower hole 8 which is a direct raw material supply port. The plasma contains the constituent elements, molecular ions, and radicals of the reaction gas, which are supplied to the substrate surface along with the flow of the reaction gas and cause a chemical reaction with the source gas molecules adsorbed on the substrate surface. Thus, a thin film is formed on the substrate. In addition, it reacts with the impurities generated at that time and desorbs from the film surface. (4) Next, an inert gas is introduced from the supply port 3 to desorb impurities adsorbed on the surface of the substrate 2. These (1) to (4) are repeated until the target film thickness is reached.

In the initial stage of film formation, it becomes a surface reaction that reacts with the raw material adsorbed on the substrate surface.
Film formation proceeds without incubation time. As shown in FIG.
An electric field is generated between two or more opposing electrodes, and ions and electrons existing in the plasma try to violently collide with the electrode, but no electric field is applied between the substrate and the plasma generating electrode. The ions and electrons in the plasma are accelerated by the electric field and do not collide with the substrate, but are carried by the gas flow and collide with the substrate, so that plasma damage does not occur.
Thus, by repeatedly supplying the source gas and the reactive gas activated by the plasma using this apparatus, a method for manufacturing a semiconductor device having excellent step coverage and adhesion, high productivity, and no plasma damage can be obtained. Can be provided.

However, when a metal film is formed by the ALD method using plasma, when a metal film is formed on the surface of the counter electrode unit shown in FIG. 2, an electric field extending between the counter electrodes is formed on the metal film. Since it is shielded, there is a risk that plasma will not be generated. In this case, as shown in FIG. 3, the counter electrode unit 5 is disposed at a position closer to the film formation substrate 2 than the shower head 12 including the shower hole 8, and as shown in FIG. By arranging each of the covered counter electrodes 6 and 7 with a space therebetween, a space capacity is maintained between the counter electrodes 6 and 7 even if a metal film is formed on the surface of the counter electrodes. As a result, plasma can be continuously generated as shown in FIG. Reference numeral 19 denotes a plasma generation location. Therefore, the film formation step (1
) To (4), by repeating the supply of the source gas and the plasma activated reaction gas using this apparatus, the semiconductor device has excellent step coverage and adhesion, high productivity and no plasma damage. The manufacturing method can be provided.

Next, an example of a substrate processing apparatus in which the present invention is implemented will be described with reference to FIG.
FIG. 7 is a schematic sectional view showing an example of a processing furnace of a single wafer processing apparatus in which a direct plasma unit as a substrate processing apparatus according to an embodiment of the present invention is incorporated.

As shown in FIG. 7, the reaction chamber 1 is provided with a processing table 20 that supports a substrate 2 such as a silicon wafer or a glass substrate that is a deposition target. A susceptor 21 that constitutes a part of the support and serves as a mounting plate on which the substrate is mounted is provided on the upper portion of the support base 20. A heater 22 as a heating means is provided inside the support base, and the substrate 2 placed on the susceptor 21 is heated by the heater 22. The heater 22 is controlled by a temperature controller 23 so that the temperature of the substrate 2 becomes a predetermined temperature.

An elevating mechanism 24 is provided outside the reaction chamber 1, and the elevating mechanism 24 allows the support 20 to be raised and lowered within the reaction chamber 1.

At the upper part of the support 20 in the reaction chamber 1, there are a large number of shower holes 8 as gas ejection means, and at least one pair of counter electrodes 6 and 7 for applying a high frequency for generating plasma are provided. An embedded counter electrode unit 5 is provided to face the susceptor 21. The counter electrode unit 5 is configured as shown in FIG. 2, and the counter electrode unit 5 is made of an insulator, for example, quartz, and an electrode insertion into which the counter electrode can be inserted. A hole 9 is provided. The counter electrode is a highly conductive metal, for example,
It is rod-shaped such as Al or Ni. The counter electrodes 6 and 7 are embedded in the electrode insertion hole 9, and the counter electrodes 6 and 7 are connected together and connected to the insulating transformer 11. By using a high frequency power supply unit 13 for the insulating transformer 11 and applying a high frequency voltage, plasma is generated on the surface of the counter electrode unit 5 as shown in FIG. That is, near the upper surface of the counter electrode unit 5 in the space between the ceiling wall of the reaction chamber 1 and the counter electrode unit 5 and near the lower surface of the counter electrode unit 5 in the space between the counter electrode unit 5 and the substrate 2. Plasma is generated. In addition, the source gas and the reaction gas supplied from the supply port 4 and the supply port 3 are respectively ejected separately or simultaneously in a shower shape from the shower hole 8 of the counter electrode unit 5. It can be done.

A raw material supply unit 25 for supplying a liquid raw material is provided outside the reaction chamber 1,
A liquid raw material supply pipe 26 and a liquid raw material flow rate controller 29 as a flow rate controller for controlling the liquid raw material supply amount are connected to a vaporizer 30 for vaporizing the liquid raw material. The raw material supply unit 25 stores a liquid raw material 28, and the liquid raw material 28 is supplied to the vaporizer 30 by the pressure of an inert gas such as He or Ar supplied from the pumping line 27. A raw material gas supply pipe 31 is connected to the vaporizer 30, and the raw material gas supply pipe 31 is connected to the raw material gas supply port 4 via a valve 32. As the liquid source, for example, an organometallic material that is liquid at room temperature, that is, an organometallic liquid source is used. Alternatively, if the raw material is solid at room temperature but becomes liquid when heated to several tens of degrees, the raw material supply unit 25,
A heater for heating the liquid source supply pipe 26 and the liquid source flow rate control device 29 to about several tens of degrees can be provided and used.

An inert gas supply unit 33 is provided outside the reaction chamber 1. The inert gas supply unit 33 supplies an inert gas as a non-reactive gas to the vaporizer 30 as a carrier gas. A carrier gas supply pipe 34 is connected. The carrier gas supply pipe 34
It is connected to the vaporizer 30 via a gas flow rate control device 35 as a flow rate controller for controlling the supply flow rate of the carrier gas. Inside the vaporizer 30, the liquid raw material 28 is ejected together with the carrier gas to increase the vaporization efficiency. As the inert gas, for example, Ar, He, N2 or the like is used.

A purge gas supply pipe 36 for supplying an inert gas as a non-reactive gas to the source gas supply pipe 31 as a purge gas is connected to the inert gas supply unit 33.
The purge gas supply pipe 36 is connected to the source gas supply pipe 31 via a gas flow rate control device 37 as a flow rate controller for controlling the supply flow rate of the purge gas and a valve 38.

When the source gas vaporized by the vaporizer 30 is not supplied from the source gas supply pipe 31 to the source gas supply port 4, the valve 32 is closed, the valve 39 is opened, and the source gas bypass pipe 4
Flow source gas to zero. At this time, by opening the valve 38 and supplying an inert gas from the purge gas supply pipe 36, the piping of the source gas supply port 4 from the valve 32 of the source gas supply pipe 31, the counter electrode unit 5, and It becomes possible to remove the source gas adsorbed on the surface of the reaction chamber 1.

A reaction gas supply unit 41 for supplying a reaction gas is provided outside the reaction chamber 1 and is supplied to the reaction gas supply pipe 42. The reaction gas supply pipe 42 is connected to the reaction gas supply port 3 via a gas flow rate control device 43 as a flow rate controller for controlling the gas supply amount and a valve 44.

The inert gas supply unit 33 is connected to a purge gas supply pipe 45 for supplying an inert gas as a non-reactive gas to the reaction gas supply pipe 42 as a purge gas.
The purge gas supply pipe 45 is connected to the reaction gas supply pipe 42 via a valve 47 to a gas flow rate control device 46 as a flow rate controller for controlling the supply flow rate of the purge gas.

When the reactive gas is not supplied from the reactive gas supply pipe 42 to the reactive gas supply port 3,
The valve 44 is closed, the valve 48 is opened, and the reaction gas is caused to flow through the reaction gas bypass pipe 49. At this time, by opening the valve 47 and supplying an inert gas from the purge gas supply pipe 45, the piping of the reaction gas supply port 3 from the valve 44 of the reaction gas supply pipe 42,
It becomes possible to remove the reaction gas adsorbed on the surfaces of the counter electrode unit 5 and the reaction chamber 1.

A cleaning gas supply unit 5 for supplying a cleaning gas is provided outside the reaction chamber 1.
0 is provided and supplied to the cleaning gas supply pipe 51. The cleaning gas supply pipe 51 is connected to the reactant gas supply port 3 via a gas flow rate control device 52 as a flow rate controller for controlling the gas supply amount and a valve 53.

An exhaust port 10 is provided in the lower part of the side wall of the reaction furnace 1, and the exhaust port 10, the vacuum pump 54, the raw material recovery trap 57 and a detoxifying device (not shown) are connected by an exhaust pipe 56. Also,
The exhaust pipe 56 is provided with a pressure controller 55 that adjusts the pressure in the reaction chamber 1.

A substrate loading / unloading port 59 is provided on the side surface of the reaction chamber 1 opposite to the exhaust port 10, and the substrate loading / unloading port 59 is provided by a gate valve 60 as a partition valve with the vacuum substrate transfer chamber 58. The substrate 2 is opened and closed, and the substrate 2 can be carried into and out of the processing chamber 1 from the substrate carry-in / out port 59.

FIG. 7 shows an example in which the counter electrode unit 5 itself is a shower head, but FIG. 8 shows a case where the shower head 12 and the counter electrode unit 5 are independent. The parts other than the shower head 12 and the counter electrode unit 5 are the same as in FIG.

At least one or more sets of counter electrodes for applying a high frequency for generating plasma are opposed to the deposition target substrate 2 and are closer to the source gas and reaction gas supply port 8 directly to the deposition target substrate. A configuration example in the case where it exists will be described below with reference to FIGS. In this case, the shower head 12 and the counter electrode unit 5 having a plurality of direct supply ports 8 of the source gas and the reaction gas to the film formation substrate 2 are arranged so as to face the film formation substrate 2. Specifically, the shower head 12 is disposed to face the counter electrode unit 5, and the counter electrode unit 5 is disposed to face the film formation substrate 2. As shown in FIG. 9, the counter electrode unit 5 has a hole (through hole) on the side surface of the holding electrode plate 14 having a circular opening (through hole) 14a in the center.
15 is inserted, and an electrode tube 16 made of an insulator such as quartz is inserted therein, and rod-like electrodes 6 and 7 made of a material such as Al or Ni are embedded in the tube, Provided.
In order to keep the reaction chamber 1 in a vacuum, the electrode tube 16 is vacuum sealed with an O-ring 17 against the inner wall of the hole 15 of the electrode plate 14. The counter electrodes 6 and 7 are connected together and connected to the insulating transformer 11. When a high frequency voltage is applied to the insulating transformer 11 by the high frequency power supply unit 13, plasma is generated on the surface of the counter electrode unit 5 as shown in FIG. 6. That is, the shower head 12 and the counter electrode unit 5
Plasma is generated near the upper surface of the counter electrode unit 5 in the space between and the lower surface of the counter electrode unit 5 in the space between the counter electrode unit 5 and the substrate 2.

Next, a method for depositing a thin film on a substrate as one step of a semiconductor device manufacturing process using the substrate processing apparatus having the above-described configuration will be described.

Below, CVD (Chemical Vapor Deposition) using organometallic liquid raw material that is liquid at room temperature
Method, especially MOCVD (Metal Organic Chemical Vapor Deposition) method or ALD (Atomi)
The case where a thin film is formed on a substrate by the c Layer Deposition method will be described with reference to FIG.
In the following description, the operation of each part constituting the substrate processing apparatus is the main controller 6.
1 is controlled.

When the gate valve 60 is opened and the substrate loading / unloading port is opened with the support 20 lowered to the substrate transfer position, the substrate 2 is loaded into the processing chamber 1 by a substrate transfer machine (not shown). Is done. At this time, the support 20 is in the transfer position by the lifting mechanism. At the transfer position, the tip of the substrate push-up pin 62 is higher than the surface of the support table 20, and the loaded substrate 2 is transferred onto the substrate push-up pin (substrate loading step). After the substrate 2 is carried into the reaction chamber 1, the gate valve 60 is closed. The support 20 moves up from the transfer position to the upper substrate processing position. Meanwhile, the substrate 2 is placed on the susceptor 21 (substrate placing step).

When the support 20 reaches the substrate processing position, electric power is supplied to the heater 22 and the substrate 2 is uniformly heated to a predetermined temperature (substrate heating step). At the same time, the reaction chamber 1
The vacuum pump 54 is evacuated and controlled to a predetermined pressure (pressure adjustment step). When the substrate 2 is transported, the substrate is heated, and the pressure is adjusted, the valves 38 and 47 provided in the inert gas supply pipes 36 and 45 are opened, and the inert gas supply unit 33 is opened. Thus, an inert gas is always flowed into the reaction chamber 1. Thereby, adhesion of particles or metal contaminants to the substrate 2 can be prevented.

When the temperature of the substrate 2 and the pressure in the processing chamber 1 reach a predetermined processing temperature and a predetermined processing pressure, respectively, and stabilize, the source gas is supplied into the processing chamber 1. That is, the liquid of the organometallic liquid raw material supplied from the raw material supply unit 28 is flow-controlled by the liquid flow control device 29, supplied from the inert gas supply unit 33, and flow-controlled by the gas flow control device 35. Together with the carrier gas, it is supplied to the vaporizer 30 and vaporized. At this time, the vaporized source gas flows to the source gas bypass pipe 40 with the valve 32 closed and the first valve 39 opened, but when the vaporization amount is stabilized, the valve 39 is closed and the valve 32 is closed. The vaporized raw material gas is introduced into the reaction chamber 1 through the raw material gas supply pipe 31, guided onto the shower head 12, dispersed in a number of shower holes 8, and deposited on the substrate 2. It is supplied at a uniform concentration. (Raw gas supply process)

After the supply of the source gas is performed for a predetermined time, the valve 32 is closed, the supply of the source gas to the substrate 2 is stopped, the valve 38 is opened, and the inert gas as a purge gas is The reaction gas is introduced into the reaction chamber 1 through the source gas supply pipe 31. Thereby, the source gas supply pipe 31 and the reaction chamber 1 are purged with the inert gas, and the residual gas is removed. (Raw material gas purge process)

At this time, the valve 39 provided in the source gas bypass pipe 40 is opened, the source gas is exhausted from the gas bypass pipe 40 so as to bypass the reaction chamber 1, and the source from the vaporizer 30 is exhausted. It is preferable not to stop the gas. Since it takes time to vaporize the liquid raw material and to stably supply the vaporized raw material gas, it is allowed to bypass the reaction chamber 1 without stopping the supply of the raw material gas from the vaporizer 30. In this case, in the next source gas supply process, the source gas can be immediately supplied to the substrate 2 by simply switching the flow.

However, when the organometallic liquid raw material is very expensive, especially in the case of a noble metal such as Pt, Ir, Ru, the raw material is wasted during the time when the reaction chamber 1 is bypassed. It may be desirable to frequently stop the vaporization operation from the vaporizer and stop the wasteful use of the liquid raw material. In this case, the valve 39 provided in the source gas bypass pipe 40 is opened, the source gas is exhausted from the gas bypass pipe 40 so as to bypass the reaction chamber 1, and then the inside of the vaporizer 30. The valve (not shown) is closed and only the carrier gas is allowed to flow. (Material consumption saving material purge process)

In the next source gas supply process, in order to be able to supply the source gas to the substrate 2 immediately by switching the flow, only the carrier gas bypasses the reaction chamber 1 during the reaction gas purge process described later. In such a state, the valve in the vaporizer 30 is opened to stabilize the vaporized state.

After purging the reaction chamber 1 for a predetermined time, a reaction gas is supplied to the reaction chamber 1. That is, from the state where the valve 48 is opened and the valve 44 is closed and the reaction gas bypasses the reaction chamber 1, the valve 48 is closed and the valve 44 is opened and the reaction gas is supplied to the reaction chamber 1. After being guided upward and dispersed in a large number of shower holes 8 and supplied onto the counter electrode unit at a uniform concentration, a high frequency is applied between the counter electrodes 6 and 7, and plasma is applied. Active species such as atomic hydrogen and hydrogen ions are supplied onto the substrate 2 in accordance with the flow of the reaction gas, here hydrogen gas. (Reactive gas supply process)

After the reaction gas is supplied for a predetermined time, the valve 44 is closed, and the supply of the reaction gas to the substrate 2 is stopped. At the same time, the valve 47 is opened, and the inert gas as the purge gas The reaction gas is introduced into the reaction chamber 1 through the reaction gas supply pipe 42. Thereby, the reaction gas supply pipe 42 and the reaction chamber 1 are purged with the inert gas, and the residual gas is removed. (Reaction gas purge process)

At this time, the valve 48 provided in the reaction gas bypass pipe 49 is opened, and the reaction gas is exhausted from the gas bypass pipe 49 so as to bypass the reaction chamber 1. It is preferable not to make the reaction gas flow rate zero. Since it takes time to stabilize the reaction gas flow rate from zero to the predetermined flow rate, the reaction gas flow from the reaction gas supply unit 41 is stopped without stopping the reaction chamber 1 to flow. In the next reaction gas supply step, the reaction gas can be immediately supplied to the substrate 2 by simply switching the flow.

In the film formation of noble metals such as Pt, Ir, and Ru films, as described above, in the next source gas supply process, in order to be able to immediately supply source gas to the substrate 2 by simply switching the flow,
Several to dozens of seconds before the end time of the reaction gas purge step, with only the carrier gas from the carrier gas supply pipe bypassing the reaction chamber 1, the valve in the vaporizer 30 is opened to enter the vaporizer. Pour liquid raw material, start vaporization and stabilize the vaporized state. This is because it takes several to several tens of seconds to stabilize the vaporized state of the vaporizer 30.

After purging the reaction chamber 1 for a predetermined time, the valve 39 is closed, the valve 32 is opened, and the source gas prepared in advance to be vaporized at a stable flow rate passes through the source gas supply pipe 31. Then, it is introduced into the reaction chamber 1 and a source gas supply process is performed.

As described above, source gas supply process, source consumption saving type material purge process, reaction gas supply process,
A thin film having a predetermined film thickness can be formed on the substrate 2 by a cycle process in which the reaction gas purging step is one cycle and this cycle is repeated a plurality of times. (Thin film deposition process)

After the thin film deposition process on the substrate 2 is completed, the processed substrate 2 is carried out of the reaction chamber 1 by a procedure reverse to the substrate carrying-in process. (Substrate unloading process)

When the thin film forming process is performed by the CVD method, the substrate temperature is controlled so as to be in a temperature range in which the source gas is self-decomposed. In this case, in the raw material gas supply step, the raw material gas is thermally decomposed, and a thin film of about several to several tens of thousands (2, 3 to several atomic layers) is formed on the substrate 2. In the reactive gas supply step, impurities such as carbon atoms (C) and hydrogen atoms (H) are removed from the thin film formed on the substrate 2 by several to several tens of thousands by the active species of the reactive gas converted into plasma. .

Further, when the thin film forming process is performed by the ALD method, the substrate temperature is controlled so as to be a temperature range in which the source gas does not self-decompose. In this case, in the raw material supply process, the raw material gas is adsorbed on the substrate 2 without being thermally decomposed. In the reactive gas supply step, the raw material adsorbed on the substrate 2 and the reactive gas react with the active species activated by the plasma, thereby causing
A thin film of about 1 mm or less (1 atomic layer or less) is formed. At this time, impurities such as carbon atoms (C) and hydrogen atoms (H) mixed in the thin film can be eliminated by the active species of the reaction gas.

In the reaction furnace in the embodiment of the present invention, the processing conditions for processing the substrate by the CVD method include, for example, a processing temperature of 350 to 500 ° C. and a processing pressure of 50 when a HfO ₂ film is formed. ~ 20
At 0 Pa, Hf (MMP) ₄ (Hf (OC (CH ₃ ) ₂ CH ₂ OCH ₃ ) ₄ : tetrakis (1-methoxy-2-methyl-2-fluorooxy) -hafnium) as the organometallic liquid raw material, supply flow rate A case where 0.01 to 0.1 sccm is used, O2 as a reaction gas, and a supply flow rate of 500 to 1500 sccm is exemplified.

In the reaction furnace according to the embodiment of the present invention, the processing conditions for processing the substrate by the ALD method include, for example, when forming a Ru film, a processing temperature of 150 to 300 ° C., a processing pressure of 10 to 200P
In a, the organic metal liquid raw material is DER (2,4-Dimethylpentadienyl Ethylcyclopentadie
nyl Ruthenium, (2,4 dimethyl phenethyl ethyl cyclohexyl diruthenium)), supply flow rate 0.01-0.1sccm, reactive gas is hydrogen, oxygen, or
A case where ammonia or the like is used at a supply flow rate of 500 to 1500 sccm is exemplified.

It is a longitudinal cross-sectional view which shows the structural concept of the reactor when the shower head and counter electrode unit in embodiment of this invention are integrated. It is a top view which shows the structure of a counter electrode unit when the shower head and counter electrode unit in embodiment of this invention are integrated. It is a longitudinal cross-sectional view which shows the structural concept of the reaction furnace in case the shower head and counter electrode unit in embodiment of this invention are independent. It is a top view which shows the structure of a counter electrode unit in case the shower head and counter electrode unit in embodiment of this invention are independent. It is a conceptual diagram which shows the plasma generation image in the reaction chamber when the shower head and counter electrode unit in embodiment of this invention are integrated. It is a conceptual diagram which shows the plasma generation image in the reaction chamber in case the shower head and counter electrode unit in embodiment of this invention are independent. It is a longitudinal cross-sectional view which shows the structure of the reaction furnace when the shower head and counter electrode unit in embodiment of this invention are integrated. It is a longitudinal cross-sectional view which shows the structure of the reaction furnace in case the shower head and counter electrode unit in embodiment of this invention are independent. It is an arrow line view from the C direction in FIG. 3 of a counter electrode unit in case the shower head and counter electrode unit in embodiment of this invention are independent.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Reaction chamber 2 Substrate 3 Reaction gas supply port 4 Raw material gas supply port 5 Counter electrode unit 6 Electrode 7 Electrode 8 Shower hole 9 Electrode insertion hole 10 Exhaust port 11 Insulation transformer 12 Shower head 13 High frequency power supply unit 14 Counter electrode unit 15 Quartz tube Insertion hole 16 Quartz electrode tube 17 O-ring 18 Plasma generation point 19 Plasma generation point 20 Support base 21 Susceptor 22 Heater 23 Temperature controller 24 Elevating mechanism 25 Raw material supply unit 26 Liquid raw material supply pipe 27 Pressure feed line 28 Liquid raw material 29 Liquid raw material flow rate control Apparatus 30 Vaporizer 31 Source gas supply pipe 32 Valve 33 Inert gas supply unit 34 Carrier gas supply pipe 35 Gas flow rate control device 36 Purge gas supply pipe 37 Gas flow rate control device 38 Valve 39 Valve 40 Source gas bypass pipe 41 Reaction gas supply unit 42 reactions Gas supply pipe 43 Gas flow control device 44 Valve 45 Purge gas supply pipe 46 Gas flow control device 47 Valve 48 Valve 49 Reactive gas bypass pipe 50 Cleaning gas supply unit 51 Cleaning gas supply pipe 52 Gas flow control device 53 Valve 54 Vacuum pump 55 Pressure Controller 56 Exhaust pipe 57 Raw material recovery trap 58 Vacuum substrate transfer chamber 59 Substrate loading / unloading port 60 Gate valve 61 Main controller 62 Substrate push-up pin

Claims (4)

Subsequent to the process of supplying the source gas, the process of forming a thin film on the substrate by supplying the reaction gas excited by plasma is repeated as one step, so-called CVD (Chemical Va
por deposition) method or ALD (Atomic Layer Chemical Vapor Deposition) method for manufacturing a semiconductor device, wherein the plasma generation unit faces the deposition substrate, and the deposition substrate of the source gas and the reactive gas Uses plasma generated by a high frequency applied between at least one pair of electrodes disposed at the same position as the direct supply port or at a position closer to the deposition target substrate than the supply port. A method for manufacturing a semiconductor device. The source gas is Al, Si, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Sr, Y, Zr, Nb,
Mo, Ru, Rh, Pd, Ag, In, I, Ba, La, Hf, Ta, W, Re, Os, Ir, Pt, Au, Pb, Bi, Ce, Pr
, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and at least one kind of gas containing at least one element selected from the group consisting of: H, He, N, O,
2. The method of manufacturing a semiconductor device according to claim 1, wherein the gas is at least one kind of gas containing at least one element selected from the group consisting of F, Ne, Cl, Ar, Kr, and Xe. Subsequent to the process of supplying the source gas, the process of forming a thin film on the substrate by supplying the reaction gas excited by plasma is repeated as one step, so-called CVD (Chemical Va
In a substrate processing apparatus by a por deposition (Pode Deposition) method or an ALD (Atomic Layer Chemical Vapor Deposition) method, the plasma generation unit faces the deposition substrate, and a source gas and a reactive gas are applied to the deposition substrate. Use plasma generated by a high frequency applied between at least one pair of electrodes arranged at the same position as the direct supply port, or at a position closer to the deposition target substrate than the supply port. A substrate processing apparatus. The source gas is Al, Si, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Sr, Y, Zr, Nb,
Mo, Ru, Rh, Pd, Ag, In, I, Ba, La, Hf, Ta, W, Re, Os, Ir, Pt, Au, Pb, Bi, Ce, Pr
, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and at least one kind of gas containing at least one element selected from the group consisting of: H, He, N, O,
4. The substrate processing apparatus according to claim 3, wherein the substrate processing apparatus is at least one kind of gas containing at least one element selected from the group consisting of F, Ne, Cl, Ar, Kr, and Xe.

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