WO2004042112A1

WO2004042112A1 - Cvd method using metal carbonyl gas

Info

Publication number: WO2004042112A1
Application number: PCT/JP2003/014152
Authority: WO
Inventors: Tatsuo Hatano; Hideaki Yamasaki
Original assignee: Tokyo Electron Limited
Priority date: 2002-11-06
Filing date: 2003-11-06
Publication date: 2004-05-21
Also published as: JP2004156104A; JP4126219B2

Abstract

A CVD method for forming a certain metal film on a substrate to be processed using a metal carbonyl gas is carried out by repeating a supplying step (S4) and a removing step (S5) many times. In the supplying step (S4), the substrate is substantially kept heated at a first temperature and the metal carbonyl gas is supplied into a vacuum chamber while exhausting the vacuum chamber at a first exhausting power. In the removing step (S5) following the supplying step, the supply of the metal carbonyl gas is stopped and the vacuum chamber is quickly exhausted at a second exhausting power which is sufficiently higher than the first exhausting power, thereby removing a decomposed gas formed through decomposition of the metal carbonyl gas.

Description

Specification

C V D method using metal carbonyl gas

Technical field

The present invention relates to a CVD (Chemical Vapor Deposition) method for forming a metal film such as tungsten (W) on a substrate to be processed using a metal carbonyl gas, and more particularly, to a semiconductor processing method for manufacturing a semiconductor device. Related to the CVD method used in the field. Here, semiconductor processing refers to the definition of semiconductor layers, insulating layers, conductive layers, etc. on substrates to be processed, such as semiconductor wafers and glass substrates for LCDs (Liquid Crystal Displays) and FPDs (Flat Panel Displays). By forming the substrate with the above-described pattern, various processes performed for manufacturing a structure including a semiconductor device, a wiring connected to a semiconductor device, an electrode, and the like on the substrate to be processed are performed. means.

Background art

In a semiconductor device, tungsten (W) is used as a wiring material of a wiring structure or a material of an interdiffusion barrier. For example, in this case, the W film fills a contact hole or a via hole formed in an interlayer insulating film on a semiconductor wafer as a substrate to be processed, or covers an inner surface of these holes. It is formed as follows.

Conventionally, PVD (Physical Vapor Deposition), typically sputtering, has been used as a method of forming a W film. It is difficult to accommodate the ledge. Such reason force, near In recent years, CVD has been used as a method for forming the W film, which can sufficiently cope with miniaturization of devices.

For example, as a processing gas for forming a W film by CVD, fusiden tungsten (WF e) and H 2 gas, which is a reducing gas, are used. In WF e

+ 3 H ₂ → W + 6 HF reaction, whereby a W film is formed on the wafer ο However, in recent years, the design rule has been increasingly miniaturized. The use of the contained gas causes F to die on the quality of the get oxide film, affecting the device and causing device failure.

On the other hand, Patent Documents 1, 2, and 3 below disclose tungsten compound luponyl (w (CO) 6), which is an organic compound gas, as a processing gas containing no F in order to form a W film by CVD. It is stated that it is used. Also, Non-Patent Document 1 below describes that a metal film is formed by CVD using a metal force luponyl such as W (co) 6. Further, in Patent Document 4 below,

It is disclosed that a W film is formed on a semiconductor device by CVD using W (co) 6. W (CO) ₆ metal force zone Les ball nil Do you Yo of promise as aヽCVD of the Soviet Union Sugasu because there is no Ji raw evil shadow fireman's standard to the device that by the Yo I Do not F ofヽWF ₆ is there.

Patent Document 1: Japanese Patent Application Laid-Open No. H02-202570

Patent Document 2: Japanese Patent Application Laid-Open No. H4-17-139776

Patent Document 3: Japanese Patent Application Laid-Open No. Hei 21-136

Patent Document 4: Japanese Patent Application Laid-Open No. 2000-112

Non-Patent Document 1: J. Vac. Scl. Technol., 14 (2), Mar / Apr, pp. 415 -424

However, there is a problem with the use of metallic compounds such as W (C O) 6. In other words, Co generated during the decomposition of such a metallic carbon gas has a strong affinity for the metal, so that the Co is adsorbed on the surface of the base and incorporated into the metal film as an impurity. Therefore, the electric resistance of the metal film is high (see Non-Patent Document 1, right column of page 417).

Metallic carpinoles such as (C o) 6 have not been put to practical use despite promising as CVD soot gas

Disclosure of the invention

SUMMARY OF THE INVENTION An object of the present invention is to provide a CVD method using metal-powered gas, which has a low electric resistance without causing an adverse effect due to a decomposition gas such as CO generated by the decomposition of metal-powered gas. Consists of forming a film on a substrate to be processed

First aspect of the present invention? Is a CVD method for forming a predetermined metal film on a substrate to be processed using a metal gas.

Preparation of heating the substrate to the first temperature at which the metallic gas is decomposed in the vacuum chamber in order to apply a true pressure to the inside of the vacuum chamber for storing the substrate.

While the substrate is substantially heated to the first temperature, while exhausting the inside of the vacuum chamber with the first exhaust power, the metal gas is introduced into the chamber and the chamber. The supply step and the force that stops the supply of the metal gas after the supply step, and the inside of the vacuum chamber is more than the first discharge force.急速 u A removal step for removing the decomposition gas generated by the decomposition of the metal carbon gas;

, '

程 repeating the supplying step and the removing step a number of times.

A second aspect of the present invention relates to a CVD method for forming a predetermined metal film on a substrate to be processed by using a metal gas, such as a metal gas, and setting a vacuum pressure in a vacuum chamber for accommodating the substrate. Do

"!

And a preparation step of heating the substrate to a first temperature at which the self-repellent gas is decomposed in the vacuum chamber;

While the substrate is substantially heated to the first temperature, the vacuum chamber is evacuated at the first exhaust capacity while the HU metal canopy is inserted into the vacuum chamber. Following the supply step of supplying the non-reactive gas, the supply of the metal-powered non-repellent gas is stopped, and the inside of the vacuum chamber is evacuated with the second exhaust power while By purging by supplying a purge gas into the vacuum chamber, a removal process for removing a decomposition gas generated by the decomposition of the metal calporal gas,

,

程 repeating the supply step and the removal step many times.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram schematically showing a CVD device according to one embodiment of the present invention.

FIG. 2 is a flowchart showing a CVD method according to an embodiment of the present invention.

Figures 3A and 3B illustrate the film formation state of the conventional CVD method. Fig.

4A to 4D are schematic views for explaining a film formation state by the CVD method according to one embodiment of the present invention.

FIG. 5 is a diagram schematically showing a CVD device according to another embodiment of the present invention.

Figure 6 is a graph showing the resistivity of the W film formed under different conditions.

Best way to implement

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, components having substantially the same functions and configurations will be denoted by the same reference numerals, and redundant description will be omitted when necessary. Only row o

FIG. 1 is a view schematically showing a CVD apparatus according to one embodiment of the present invention. The o-film forming apparatus 100 is a substantially air-tightly formed, substantially cylindrical-, empty channel (processing chamber). ) Has one. A susceptor 2 for horizontally supporting a substrate W to be processed is disposed in the processing chamber 1. The susceptor 2 is supported by a cylindrical support member 3 provided at the lower center thereof.

At the outer edge of the susceptor 2, a guide for guiding the wafer W and a wing 4 are arranged. A resistance heating type heater 5 is embedded in the susceptor 2. The heater 5 heats the susceptor 2 by means of the heater power supply 6 and heats the heat of the susceptor 2 and heats the substrate W to be processed. (CO) 6 gas is thermally decomposed The container 2 is 300 to 600, which is convenient for film formation. Heated to a predetermined temperature of c. A heater (not shown) is connected to the heater power supply 6. By this controller,

The output of the heater 5 is controlled according to the signal of the ijm. degree sensor (not shown). A heater (not shown) is also embedded in the wall of the processing room 1. With this heater, the wall force of the processing chamber 1 is 0 to 80. Heated to about c.

On the top wall 1a of the processing room 1, -y 10 is installed to the shower. At the bottom of the Shah Wa one plates 1 0 a of head 1 0 Shah Wa ¹ to ~ plurality of gas injection holes 1 1 for discharging gas toward the susceptor 2 is formed. At the upper end of the shower head 10, a pipe 12 for supplying a processing gas, for example, a W (Co) ₆ gas, is connected. A space 10 c for diffusing the light is formed. The gas discharge port 11 communicates with the space 10 c to uniformly supply the processing gas into the processing 1. Further, in the shower plate 10a, for example, a concentric refrigerant flow passage 10b is formed to prevent the decomposition of the W (cO) ₆ gas in the shower head 10. . A coolant such as cooling water is supplied to the coolant flow path 10b from a coolant supply (not shown), and the coolant is controlled to a shear plate 10a power S20-: L00 ° C.

The other end of the pipe 12 is inserted into a film forming material container 13 containing a solid W (CO) 6 material S as a film forming material. In addition, the carrier 13 also includes a carrier gas pipe 14. From the carrier gas supply source 15, for example, an Ar gas is blown into the film forming material container 13 as a carrier gas via a pipe 14. By supplying the carrier gas, the solid W (C O) ₆ raw material S is sublimated to W (CO) ₆ gas. The w (c O) ₆ gas is carried by the carrier gas and supplied to the shower head 10 via the pipe 12, is diffused in the space 10 c, and is discharged into the gas discharge hole 11. Is supplied to processing chamber 1 via

The piping 14 is provided with a mass flow controller 16 and valves 17 before and after the mass flow controller 16. Also, for example, W (C

0) _6. Flowmeter to grasp the flow rate based on the amount of gas

4 5 and the valves 17 before and after it are arranged. Flow meter for piping 1 2

A pre-flow line 41 is connected downstream of 45. The pre-flow line 41 is connected to an exhaust pipe 24 described later. The pre-flow line 41 is provided with a valve 42 immediately downstream of a branching point from the W (CO) 6 gas pipe 12. Piping 1 2, 1 4,

41 A heater (not shown) is provided around 1. The heater is at a temperature at which the W (CO) ₆ gas does not solidify, for example, 20 to 1.

0 0. c される It is preferably controlled at 25 to 60 ° C.

On the other hand, a purge gas pipe 18 is connected to the pipe 12. Nono ⁰ one purge gas and the other end of the pipe 1 8 Pas one purge gas supply source 1 9 connected to a purge gas supply source 1 9, and a purge gas, eg if A r gas, H e gas, which N _two gas Supply inert gas, Η2 gas, etc. The purge gas pipe 18 is provided with a mass controller 20 and valves 21 before and after it.

Mass flow controller 16, 20, Knob 17, 21,

42 is controlled by the controller 40. As a result, the supply / stop of the carrier gas, the W (CO) ₆ gas, and the purge gas, and the flow rates thereof are controlled. W (CΟ) ₆ Gas flow rate The flow meter 45 for grasping is also connected to the controller 40, and the control port 40 is provided with a flow meter so that a desired W (CO) ₆ gas flow value can be obtained. 45 Controls the carrier flow mass flow π 16 based on the value of 45

A circular opening 22 is formed at the center of the bottom wall 1 b of the processing chamber 1. The bottom wall 1b is provided with an exhaust chamber 23 communicating with the opening 22 and protruding downward. An exhaust pipe 24 is connected to the side of the exhaust 23. The exhaust pipe 24 has a valve 25a for adjusting the pressure and exhaust capacity inside the processing chamber 1 and a high-speed vacuum pump.

Discharge device 25 including 25 b is connected. By operating the exhaust device 25, it is possible to rapidly reduce the pressure in the processing chamber 1 to a predetermined degree of vacuum.

The susceptor 2 is provided with three support pins 26 (only two are shown) for supporting and raising and lowering the wafer w. Support pin

Reference numeral 26 denotes a susceptor 2 which is provided so as to be able to protrude and retract with respect to the surface thereof. The lower end of the support pin 26 is fixed to the support plate 27. Support pin 2

6 is moved up and down by a driving mechanism 28 such as an air cylinder via a support plate 27.

On the side wall of the processing chamber 1, a loading / unloading port 29 for loading / unloading the wafer W with respect to a transfer chamber (not shown) adjacent to the film forming apparatus 100 is formed. The loading / unloading port 29 is opened and closed by a gate valve 30.

FIG. 2 is a flowchart showing a CVD method according to one embodiment of the present invention, in which a W film is formed using such a film forming apparatus. First, the gate knob 30 is opened and the loading / unloading port 29 The wafer W is loaded into the processing chamber 1 and placed on the susceptor 2 (step S 1). Next, the susceptor is heated by the heater 5, and the wafer W is heated to 300 to 600 ° C. by the heat (step S 2). Further, the inside of the processing chamber 1 is evacuated by the exhaust device 25, and the pressure in the processing chamber 1 is evacuated to a predetermined pressure, for example, 6.7 Pa or less (step S3). Thereafter, a W film is deposited on the surface of the underlying film formed on the wafer W. The W film is deposited by using a W (CO) ₆ supply step (step S4) and a CO removal step (step S5).

In the W (CO) ₆ supply step (step S 4), a carrier gas, for example, Ar gas is blown into the solid W (CO) ₆ raw material S stored in the film forming raw material container 13, and W (CO CO) ₆ Sublimates the raw material S. Then, the generated W (CO) ₆ gas is carried by the carrier gas and introduced into the processing chamber 1 through the pipe 12 and the shower head 10. During the process S 4, the exhaust unit 25 is operated at the first exhaust speed (first exhaust capacity) to exhaust the inside of the processing chamber 1. At this time, while the vacuum pump 25b is operated with the same output as in the step S3, the necessary first pumping capacity is obtained by adjusting the valve 25a.

After supplying the W (CO) ₆ gas to the surface of the wafer W for a predetermined time, the process shifts to a CO removal step (step S5). In the CO removal process (process S5), the supply of W (CO) ₆ gas is stopped (the supply of carrier gas is stopped), and the exhaust device 25 is set to a sufficiently higher speed than the first exhaust speed described above. Operate at the second pumping speed (second pumping capacity) to rapidly exhaust the inside of the processing chamber 1. At this time, vacuum port By operating the pump 25b with the same output as in the step S4, the necessary second exhaust capacity is obtained by adjusting the valve 25a. As a result, the CO gas generated by the decomposition of the W (CO) ₆ gas is removed from the processing chamber 1. The second exhaust capacity is preferably 3 to 700 times, more preferably 3 to: L00 times the first exhaust capacity. A pump that can provide a difference in exhaust capacity of 700 times or more has a high cost and is not preferable. The exhaust capacity of the exhaust pump is preferably 1 OOOOLZ sec or less.

The number of repetitions of the step of supplying W (CO) ₆ (step S 4) and the step of removing CO (step S 5) depends on the final thickness of the W film to be formed, but usually at least. Repeat 10 times or more. At this time, supply, stop, and control of the flow rate of the W (CO) ₆ gas, and adjustment of the valve 25a of the exhaust device 25 are performed in accordance with a predetermined program previously input to the controller 40. U.

In the conventional method, W (CO) ₆ gas is continuously supplied into the processing chamber until the final thickness of the W film is reached. In this case, as shown in FIGS. 3A and 3B, first, the W (CO) ₆ gas reaches the surface of the base film on the wafer W (FIG. 3A). The W (CO) ₆ gas is decomposed, and the decomposed CO is quickly adsorbed on the site where W should be adsorbed (Fig. 3B). As a result, CO is taken into the W film, the electrical resistance increases, and the film quality deteriorates.

And pairs to this, in the embodiment of the present invention, alternating and removal by high-speed exhaust of CO gas supply and W (CO) ₆ gas W (CO) ₆ gas against the wafer W is generated by decomposition Do to In this case, in step S4, as shown in FIGS. 4A and 4B, The W (CO) 6 gas reaches the surface of the underlayer on the wafer W, and the decomposed CO is adsorbed on the site where W is to be adsorbed in a short time. However, in step S5, Co is quickly removed by the high-speed exhaust as shown in FIG. 4C. Then, as shown in FIG. 4D, when the next W (CO) ₆ gas is supplied, W (Co) ₆ is adsorbed on the adsorption site from which ヽ CO has been removed. ·> The-step is repeated to form a w film having a predetermined thickness, so that deterioration of the film quality due to CO incorporation can be prevented.

In step S4, the pressure in the processing chamber 1 is 0.10 to o66.

It is desirable to be 7 Pa. If this pressure exceeds 66 6 • 7 Pa, the film quality of the W film may be degraded. On the other hand, if this pressure is less than 0 • 10 Pa, the deposition rate is too low. Further, it is preferable that the residence time of W (CO) 6 gas be set at 100 seconds or less. The W (CO) ₆ gas flow is 0.

0 1 to 5 L Zmi ri is preferred.

When removing the co gas, instead of performing the high-speed exhaust as described above, it is also possible to introduce the purge gas from the purge gas supply source 19 while evacuating the processing chamber 1. If good, W

(co) ₆ supply process (process S 4) and CO removal process (process

In step S5), the exhaust capacity of the exhaust device 25 is maintained substantially constant, and the required process can be performed only by switching the gas. In the process (process S 4), the same gas as the carrier gas supplied into the processing chamber 1 together with the W (CO) ₆ gas can be used.

When introducing the purge gas, the pressure in the processing chamber 1 is Since it is preferable to exhaust the gas to the same pressure as at the time, for example, the gas supply amount and the exhaust gas per unit time

J.

In the supply step (step S 4) and the removal step (step S 5). However, in order to effectively remove C ο gas, the valve 25a is opened normally (with the vacuum pump 25b operated at a constant output) and the exhaust capacity of the exhaust 25 May be increased. By introducing the purge gas in this way, it becomes possible to expel the adsorbed CO more quickly.

Further, as described above, after the high-speed exhaust is performed for a certain period of time, the gas may be introduced while the exhaust is performed at a high rate, as described above, in the process of removing co (step S5). . In this case, it is preferable that the pressure in the processing chamber 1 at the time of the purging is set to be approximately the same as the pressure in the supply step (step S4).

> Yu,

The adsorption of W (cO) ₆ is relatively easy to generate at low temperatures. <ヽ The desorption of co is relatively easy to generate as ϊ¾ tun.

(C o) 6 When supplying gas, keep wafer w at a relatively low temperature.

When removing Co, it is preferable to make Jeha W relatively high. For example, the wafer temperature when supplying W (Co) 6 gas is set to 1

Set the temperature to about 0 to 400 ° C, and set the temperature at the time of C o removal to 30 ° C.

By setting the temperature to about 0 to 600 ° C., a good film forming process can be performed. In this case, σ 力 It is necessary to switch the wafer temperature in a short period of time. Therefore, it is preferable to use A 1 N or the like with high thermal conductivity as the susceptor 2 and make it as thin as possible. Instead of the resistance heating type heater 5, a lamp heating type heating With a heat source, the temperature can be changed in a short time.

Supply of W (CO) ₆ 'Process (Process S 4) \ Here, W (C

O) It is preferable that the supply amount of the _six gases at one time corresponds to the thickness of the w film of 2 nm or less. If the thickness of the film formed at one time is about this, the amount of generated co is taken in less, and it is more preferable.

This corresponds to a thickness of the W film of 1.1 nm or less.

The time for one time of the CO removal process (step S5) is from 2 seconds to

Preferably, it is 60 seconds. If this time is 2 seconds or more, the CO on the wafer W can be effectively removed. More preferably, it is 3 seconds or more.

Almost all CO can be removed. On the other hand, if the time exceeds 60 seconds, the processing efficiency decreases.

The displacement per cycle in the C〇 removal process (step S5) is 30

L to 300 L is preferred. More desirably, this displacement is less than 40 L and even more than 45 L and less than 30 L.

Effective removal of C O does not work. If it exceeds 300 L, there is a problem that it is necessary to use a high-exhaust capacity exhaust system (expensive), or it takes a long time to exhaust.

Note that the carrier gas is not limited to the Ar gas, and another inert gas may be used. Further, it is preferable that the carrier gas is a gas capable of suppressing the temperature of the processing gas to a low level. Examples of such gas include N ₂ gas, H ₂ gas, and He gas power s.

Returning to FIG. 2, after the completion of the formation of the W film, The residual gas in the processing chamber 1 is exhausted by exhausting gas (Step S6). At this time, a purge gas may be supplied from the purge gas supply source 19 as a post flow. Then, the gate knob 30 is opened, and the wafer w is unloaded from the loading / unloading port 29 (Step S7).

FIG. 5 is a diagram schematically showing a CVD device according to another embodiment of the present invention. This film forming apparatus 100 ′ has the same structure as that of FIG. 1, but is different from the apparatus of FIG. 1 only in that a reducing gas can be supplied. That is, the reducing gas pipe 31 is connected to the pipe 12, and the other end of the reducing gas pipe 31 is connected to the reducing gas supply 32. The reducing gas supply source 32 supplies, for example, H 2 gas, SiH 4 gas, or the like as a reducing gas.

The vat gas pipe 31 is provided with a muff outlet 3r and a noreb 34 before and after the muffler outlet. This is the downstream side of the π 1 controller 33. Is connected to the pre-flow line 43. The pre-flow line 43 is connected to the pre-flow line 41. In the pre-flow line 43, a valve 44 is provided immediately downstream of the branching point with the gas pipe 31. The mass controller 33 and the valves 34 and 44 are also controlled by the π inlet port 40, and the supply, stop, and flow of the 3S gas are controlled. La 4

Controlled by 0.

When a W film is formed using such a film forming apparatus shown in FIG. 5, the CO removal process (step S5) shown in FIG. Supply of reducing gas This promotes decomposition of adsorbed W (CO) ₆ and removal of C o, and can further increase the deposition rate Using the apparatus shown in Fig. 1, a W film was formed under different conditions. In the experiment, the pressure in the processing chamber 1 was set at 66.7 Ρa, the wafer temperature was set at 44 ° C, and a W film with a thickness of about 30 nm was formed under the following six film forming conditions. .

[Condition 1 ]

A W (CO) 6 gas was continuously supplied at a gas flow rate of 0.5 L / min to form a W film of 35 nm.

[Condition 2]

At a gas flow rate of 0.5 L / mi 11, W (C

O) ₆ gas was supplied (corresponding to a ^^ film with a thickness of 0.16 11 111) ₀ Subsequently, the W (CO) ₆ gas was stopped and 1

The supply and rapid evacuation as if high-speed evacuation were performed at an evacuation speed of 50 L / sec were repeated 190 times to form a w film of 30 ηm.

[Condition 3]

W (c) for 1.5 seconds at 0.5 L / min

O) ₆ gas was supplied (corresponding to a W film with a thickness of 0.16 nm) Then, the W (CO) ₆ gas was stopped and the Ar gas flow rate was 0.5 L / min for 3 seconds. (Purge speed 1

0.3 Sec) This supply and purging were repeated 190 times to form a 30 nm W film.

[Condition 4]

Gas flow ◦ .5 L / min for 1.5 seconds over W (C

Ii) ₆ gases were supplied (corresponding to a 0.17-nm-thick W film. Subsequently, the W (CO) ₆ gas was stopped, and A r Purging was performed at a gas flow rate of 0.5 L min (pumping speed 15.3 L / sec). Such supply and purging were repeated 190 times to form a 32 nm W film.

[Condition 5]

W (CO) ₆ gas was supplied at a gas flow rate of 0.5 L / min for 1.5 seconds (corresponding to a ^ film having a thickness of 0.16111111). Subsequently, the W (CO) ₆ gas was stopped, and purging was performed at an Ar gas flow rate of 0.5 L / min for 10 seconds (exhaust speed: 15.3 L / sec;). . Such supply and knowledge. The process was repeated 190 times to form a 30 nm W film.

[Condition 6]

W (CO) ₆ gas was supplied at a gas flow rate of 0.5 LZ min for 1.5 seconds (corresponding to a 0.16 11111 thick film). Subsequently, the W (CO) ₆ gas was stopped, and a high-speed evacuation was performed at a pumping speed of 150 L / sec for 5 seconds, followed by an Ar gas flow rate for 5 seconds. Purging was performed at 0.5 L / min (exhaust speed: 15.3 L / sec). With such supply and rapid exhaust. The process was repeated 190 times to form a 30 nm W film.

Figure 6 is a graph showing the resistivity of the W film formed under these conditions. As shown in Fig. 6, the conditions for continuous W film formation

At 1, the specific resistance of the W film was 300 βΩ · cm. On the other hand, under the conditions 2, 3, 4, 5, and 6 according to the embodiment of the present invention, the specific resistance of the w film was sufficiently lower than the condition 1. That is, according to the embodiment of the present invention, the specific resistance is low. It was confirmed that good film quality was obtained.

In conditions 3, 4, and 5, 3, 5, and 10 seconds were used as the time for removing CO by Ar purging, respectively. As shown in Fig. 6, c

The longer the O removal time, the lower the specific resistance of the W film.

Even when the CO removal time was the same for 10 seconds, the resistance of the W film was lower in Condition 6 in which purging was performed after evacuation than in Condition 5 in which only purging was performed.

In the above embodiment, w (Co) is used as the metallic luponyl gas.

In this example, a W film is formed using 6 gases. However, as a metal canopy gas, W (CO) 6 6 Ni

(CO) 4, Mo (CO) ₆ヽ CO2 (CO) ₈ , Rh4 (co) _12. , Re2 (CO) 10, Cr (CO) 6 ヽ RU3 (co)

12 At least one gas can be selected from the group. A person who used these gases alone

Says w,

Ni, Mo, Go oRh ヽ Re, Cr, Ru metal films can be formed respectively

Table

In the embodiment | 1, the semiconductor wafer is exemplified as the substrate to be processed. However, the substrates to be processed are LCD and F

Glass substrate for PD can be used

Industrial applicability

According to the present invention, the supply of the metallic gas to the substrate to be processed and the removal of the decomposition gas such as the gas generated by the decomposition of the metallic gas are alternately performed. For this reason, even if the decomposition gas such as CO is adsorbed on the metal film, it is quickly removed and the incorporation of the decomposition gas such as co into the film is reduced. A good quality metal film with low resistance can be formed.

Claims

The scope of the master's request

1. A CVD method for forming a predetermined metal film on a substrate to be processed using a metal carbon gas.

The pressure inside the vacuum chamber storing the substrate is set to BX at a true pressure, and the substrate is heated inside the vacuum chamber at a temperature of 1 m, which is the time when the metal gas is decomposed. About

In the state where the plate is substantially heated to the first temperature, the ftu

■,

While the inside of the vacuum chamber is evacuated with the first exhaust capacity, a supply process for supplying the metal gas gas into the vacuum chamber and a supply gas for supplying the metal gas gas to the vacuum chamber are performed. While the supply was stopped, the inside of the chamber was rapidly evacuated with the second exhaust capacity sufficiently higher than the first exhaust capacity, thereby generating the above-mentioned metal carbonyl gas by decomposition. A removal process for removing cracked gas;

Repeating the supply step and the removal step many times.

2. The method according to claim 1, wherein:

The second exhaust capacity is 3 to 700 times the first exhaust capacity.

3. The method of claim 1, wherein:

The removing step further includes a step of supplying a purge gas into the vacuum chamber to perform purging following the rapid evacuation.

4.CVD method of forming a predetermined metal film on a substrate to be processed using metal carbonyl gas,

The inside of the vacuum chamber containing the substrate is set to a vacuum pressure. And a preparation step of heating the plate to a first temperature at which 刖 H5 metallurgical gas is decomposed in a 真空 sd vacuum chamber;

With the substrate substantially heated to the first temperature / temperature of the HU,

While the inside of the vacuum chamber is evacuated with the first exhaust capability, the supply process for supplying the metal canol gas to the vacuum chamber and the metal supply force following the supply process. While stopping the supply of luponyl gas, 7

口 mouth; = 1 neck i

By discharging the inside of the D-channel with the second pumping capacity and supplying and purging the purge gas into the vacuum chamber, the metal gas is decomposed. A removal process for removing the decomposition gas generated by the

,

供給 It has a process and a process that repeat the supply process and the previous BB removal process many times.

5. Regarding the method described in claim 4

The first and second exhaust capacities are substantially the same α

6. Claim 4 4 ΰ% method

The metallized vapor gas includes a metallized liquid gas and a carrier gas, and the purge gas is composed of the same gas as the SB carrier gas.

7. In the method described in claim 1 or 4,

In the removing step, the substrate is heated to a second temperature higher than the first temperature of HH.

8. The method described in claims 1 or 4

The number of repetitions of the supply process and the removal process should be at least 10 times ο ₀

9. The method described in claims 1 or 4, The time of the removal step is 2 seconds to 60 seconds

10. The method as defined in claim 9

The displacement capacity of the removal step is S30L to 300L.

11. The method according to claim 1 or 4, wherein, in the removing step, m. Original gas is supplied into the vacuum chamber.

12. The method according to claim 1 or 4, wherein a supply amount of the metallic force gas in the supply step corresponds to a thickness of the metal film of 2 nm or less.

1 3. The method according to claim 1 or 4, wherein the metal canopy gas is W (Co) 6 ヽ Ni (Co).

_{4, M o (CO) 6} , co 2 (CO) 8ヽR h 4 (CO) 12,

At least one gas selected from the group consisting of Re2 (CO) ₁₀ , Cr (CO) ₆ , and Ru3 (CO) 12

1 4. In the method described in claim 13 ヽ

The metal canolepo gas is W (CO) 6 gas, and the SB first temperature is 300 to 600 ° C.

15. The method according to claim 3 or 4, wherein the total gas per unit time when supplying the m13 purge gas into the vacuum channel is:

The supply amount and exhaust gas are the same as in the supply process.