JP2003077863A - Method of forming cvd film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide method of forming CVD films which does not form warpages in a substrate even if the substrate is large in size. SOLUTION: In this CVD film forming method, a substrate W to be processed is placed on a board within a processing chamber 31, and a thin film is formed with the CVD on the substrate W to be processed while the substrate W is heated with a heating means 35 via the board 32. Within the processing chamber 31, first preheating is conducted to the substrate W with the heating means 35 under the condition that a substrate support pin 69 of the board 32 be lifted upward to hold the substrate W on the substrate support pin 69. Thereafter, the substrate support pin 69 is moved downward, to place the substrate W on the board 32. Here, second preheating is conducted to the substrate W. Thereafter, a film is formed to the substrate to be processed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CVD film forming method for forming a thin film such as a TiN film by CVD.

[0002]

2. Description of the Related Art In the manufacture of semiconductor devices, the circuit structure tends to have a multilayer wiring structure in response to the recent demand for higher density and higher integration. Embedding technology for electrical connection between layers, such as contact holes which are the connecting portions with the wiring layers and via holes which are the connecting portions between the upper and lower wiring layers, has become important.

Generally, Al (aluminum) or W is used to fill such contact holes and via holes.
(Tungsten) or an alloy mainly composed of these is used. In order to form a contact between such a metal or alloy and an underlying Si substrate or a poly-Si layer,
Prior to embedding these, a Ti film is formed inside the contact hole and the via hole, and a T film is formed as a barrier layer.
The iN film is formed.

Conventionally, such Ti film and TiN film have been formed using physical vapor deposition (PVD).
Recently, as device miniaturization and high integration are especially required, design rules become stricter, and line width and hole opening diameter become smaller accordingly, and PVD becomes higher. Membranes have increased electrical resistance, making it difficult to meet demands.

Therefore, these Ti film and TiN film are replaced by
The film is formed by chemical vapor deposition (CVD), which can be expected to form a film of higher quality. In forming these films, TiCl ₄ (titanium tetrachloride) is used as a film forming gas, and TiCl ₄ and H ₂ (hydrogen) are heated while a semiconductor wafer as a substrate is heated by a stage heater.
The Ti film is formed by reacting the door, TiCl ₄
By reacting NH ₃ (ammonia) with Ti
An N film is formed.

[0006]

By the way, recently, the size of a semiconductor wafer (hereinafter, simply referred to as a wafer) is 200.
Since the size of the wafer is increased from 300 mm to 300 mm, the wafer is likely to warp due to temperature change and the like in the heating process during film formation. For example, since the TiN film is heated to a high temperature of 500 to 700 ° C. by thermal CVD,
The wafer is actually warped in the preliminary heating process performed prior to the film formation. When the wafer is thus warped, a mask shift or the like occurs in a photolithography process, which is a post-process, and the wiring cannot be formed accurately. Therefore, it is extremely important in semiconductor manufacturing to prevent the wafer from warping.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a CVD film forming method in which the substrate does not warp even if the substrate is large.

[0008]

In order to solve the above-mentioned problems, a first aspect of the present invention mounts a substrate to be processed on a mounting table in a processing chamber and heats the substrate to be processed through the mounting table by heating means. A CVD film forming method for forming a thin film on a substrate to be processed by CVD while
In a state in which the substrate support pins of the mounting table are raised to hold the substrate to be processed on the substrate support pins, the substrate to be processed is first preheated by the heating means, and then the substrate support pins are lowered. Then, the substrate to be processed is placed on the mounting table, second preheating for preheating the substrate to be processed is performed, and then film formation is performed on the substrate to be processed. I will provide a.

According to a second aspect of the present invention, a substrate to be processed is placed on a mounting table in a processing chamber, and a thin film is formed on the substrate to be processed by CVD while the substrate is heated by the heating means via the mounting table. In the CVD film forming method, a process of loading a substrate to be processed into a chamber, raising a substrate support pin of a mounting table to receive the substrate to be processed, and holding the substrate to be processed on the substrate support pin. In this state, the first heating process is performed by introducing gas into the chamber which is evacuated while heating the mounting table by the heating means, and the gas is evacuated while the chamber is evacuated. Stopping the introduction, lowering the substrate support pins to place the substrate to be processed on the mounting table, and introducing a gas into the chamber while the substrate to be processed is mounted on the mounting table. 2 preheat A step, then, CVD, characterized by comprising a step of forming a film substrate to be processed
A film forming method is provided.

Further, according to a third aspect of the present invention, the substrate to be processed is placed on a mounting table in the processing chamber, and the substrate to be processed is heated by the heating means provided on the mounting table while C is applied to the substrate to be processed.
A CVD film forming method for forming a TiN thin film by VD, comprising a step of loading a substrate to be processed into a chamber, raising a substrate support pin of a mounting table to receive the substrate to be processed thereon, and the substrate support pin A step of performing a first preliminary heat treatment by introducing an inert gas into the chamber which is evacuated while heating the mounting table by the heating means while holding the substrate to be treated thereon; Stopping the introduction of the inert gas in a state where the inside is evacuated, placing the substrate to be processed on the mounting table by lowering the substrate support pins, and the state in which the substrate to be processed is mounted on the mounting table. And a step of introducing a reaction gas containing an inert gas and nitrogen into the chamber to perform second preheating, and thereafter,
And a step of further introducing a reaction gas containing Ti into the chamber to form a TiN film on the substrate to be processed.

According to the present invention, prior to the preheating performed by placing the substrate to be processed on the mounting table, the substrate supporting pins of the mounting table are raised in the processing chamber to place the substrate to be processed on the substrate supporting pins. Since preheating is performed while the substrate is held, the substrate to be processed is not heated rapidly as in the case where the substrate to be processed is immediately placed on a heated table, and the thermal stress of the substrate to be processed is not increased. Therefore, even if the substrate to be processed is large, it is possible to prevent warpage.

In the first aspect of the invention, the first preheating is performed while the substrate support pins of the mounting table are raised to hold the substrate to be processed on the substrate support pins, and the substrate support pins are lowered to be processed. Secondly, mounting the substrate on the mounting table
It is preferable to carry out the pre-heating while introducing gas into the chamber. As a result, the heating efficiency of the substrate to be processed is increased, so that the preheating time can be completed in a short time.

Further, the second invention may further comprise a step of gradually increasing the gas pressure in the chamber with the substrate to be processed placed on the mounting table, prior to the step of performing the second preheating. Preferably, in the third invention, prior to the step of performing the second preheating, the inert gas and nitrogen are introduced into the chamber while the substrate to be processed is placed on the placing table so that the gas pressure is gradually increased. It is preferable to further include a step of introducing. By adding such a step, the gas pressure in the chamber is prevented from rapidly increasing in the second preheating, and the stress exerted on the substrate to be processed is relaxed.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be specifically described below with reference to the accompanying drawings. FIG. 1 is a schematic configuration diagram showing a multi-chamber type film forming system equipped with a TiN film forming apparatus for carrying out the method of the present invention.

As shown in FIG. 1, this film forming system 10
0 has two Ti film forming devices 1 and 2 for forming a Ti film by CVD and two TiN film forming devices 3 and 4 for forming a TiN film by CVD, for a total of four film forming devices. The film forming apparatuses 1, 2, 3 and 4 are provided corresponding to the four sides of the hexagonal wafer transfer chamber 5, respectively. Load lock chambers 6 and 7 are provided on the other two sides of the wafer transfer chamber 5, respectively. A wafer loading / unloading chamber 8 is provided on the opposite side of the load transfer chambers 6 and 7 from the wafer transfer chamber 5, and a wafer W can be accommodated on the opposite side of the wafer loading / unloading chamber 8 from the load lock chambers 6 and 7. Ports 9 and 1 for attaching the three large hoops (FOUP) F
0 and 11 are provided. The Ti film forming apparatuses 1 and 2 and the TiN film forming apparatuses 3 and 4 have the same structure.

The Ti film forming apparatuses 1 and 2, the TiN film forming apparatuses 3 and 4, and the load lock chambers 6 and 7 are connected to each side of the wafer transfer chamber 5 through a gate valve G as shown in FIG. These are communicated with the wafer transfer chamber 5 by opening the gate valves G, and are shut off from the wafer transfer chamber 5 by closing the gate valves G. A gate valve G is also provided in a portion of the load lock chambers 6 and 7 connected to the wafer loading / unloading chamber 8. The load lock chambers 6 and 7 are opened / closed by opening the gate valve G. 8 and is closed from the wafer loading / unloading chamber 8 by closing them.

In the wafer transfer chamber 5, a Ti film forming apparatus 1,
2, TiN film forming devices 3 and 4, and load lock chamber 6
7, a wafer transfer device 12 for loading and unloading the wafer W, which is the object to be processed, is provided. The wafer transfer device 12 is disposed in the approximate center of the wafer transfer chamber 5,
Two blades 14a and 14b for holding the wafer W are provided at the tip of the rotating / expanding / contracting portion 13 which can be rotated and expanded / contracted. Is attached to. The inside of the wafer transfer chamber 5 is kept at a predetermined vacuum level.

A HEPA filter (not shown) is provided on the ceiling of the wafer loading / unloading chamber 8, and clean air that has passed through the HEPA filter is supplied into the wafer loading / unloading chamber 8 in a downflow state. The wafer W is loaded and unloaded in a clean air atmosphere at atmospheric pressure. Three ports 9 and 1 for attaching the hoop F of the wafer loading / unloading chamber 8
A shutter (not shown) is provided on each of the ports 0 and 11, and an empty hoop accommodating a wafer W is directly attached to these ports 9, 10 and 11, and the shutter is removed when attached to the outside air. Of the wafer carrying-in / carrying-out chamber 8 while preventing the entry of the wafer. Also,
The alignment chamber 1 is provided on the side surface of the wafer loading / unloading chamber 8.
5 is provided, and the wafer W is aligned there.

In the wafer loading / unloading chamber 8, there is provided a wafer transfer device 16 for loading / unloading the wafer W to / from the hoop F and loading / unloading the wafer W to / from the load lock chambers 6, 7. The wafer transfer device 16 has a multi-joint arm structure, and the rail 1 is arranged along the arrangement direction of the hoops F.
The wafer W is placed on the hand 17 at the tip of the wafer 8 and is transferred.

In such a film forming system 100, first, one wafer W is taken out of any one of the FOUPs F by the wafer transfer device 16 in the wafer loading / unloading chamber 8 held in the clean air atmosphere at atmospheric pressure. Then, the wafer W is loaded into the alignment chamber 15 and the wafer W is aligned.
Next, the wafer W is loaded into one of the load lock chambers 6 and 7, the inside of the load lock is evacuated, and then the wafer in the load lock is taken out by the wafer transfer device 12 in the wafer transfer chamber 5. Is charged into the Ti film forming apparatus 1 or 2 to form a Ti film, and the wafer W after Ti film formation is continuously inserted into the TiN film forming apparatus 3 or 4 to form a TiN film. After that, the wafer W after the film formation is loaded into one of the load lock chambers 6 and 7 by the wafer transfer device 12 and returned to atmospheric pressure, and then the load lock is performed by the wafer transfer device 16 in the wafer loading / unloading chamber 8. The wafer W in the chamber is taken out and stored in one of the FOUPs F.
Such an operation is performed for one lot of wafers W and 1
The processing of the set ends. By such a film forming process,
As shown in FIG. 2, a Ti film 23 as a contact layer and a TiN film 24 as a barrier layer are formed in a contact hole 22 formed in the interlayer insulating film 21 and reaching the impurity diffusion region 20a. After that, by another device,
A film of Al, W, or the like is formed to fill the contact hole 22 and form a wiring layer.

Next, the TiN film forming apparatus 3 for carrying out the CVD film forming method of the present invention will be described. In addition, as described above, the TiN film forming apparatus 4 has the completely same structure. Figure 3
FIG. 3 is a cross-sectional view showing a TiN film forming apparatus for performing the CVD film forming method according to the present invention. The TiN film forming apparatus 3 has an airtightly configured substantially cylindrical chamber 31 in which a susceptor 32 for horizontally supporting a wafer W to be processed is provided in the lower center part. It is arranged in a state of being supported by the provided cylindrical supporting member 33. A guide ring 34 for guiding the wafer W is provided on the outer edge of the susceptor 32. Further, a heater 35 is embedded in the susceptor 32, and the heater 35 is heated by a heater power supply 36 to heat the wafer W, which is a substrate to be processed, to a predetermined temperature. The susceptor 32 can be made of ceramics such as AlN, and in this case, a ceramics heater is formed.

A shower head 40 is provided on the ceiling wall 31a of the chamber 31 via an insulating member 39.
The shower head 40 includes an upper block body 40a, a middle block body 40b, and a lower block body 40c. Then, discharge holes 47 and 48 for discharging gas are alternately formed in the lower block body 40c. The first gas inlet 41 is provided on the upper surface of the upper block body 40a.
And a second gas introduction port 42 are formed. In the upper block body 40a, a large number of gas passages 43 are branched from the first gas inlet 41. Middle block body 40
The gas passage 45 is formed in b.
3 communicates with these gas passages 45 through a horizontally extending communication passage 43a. Further, the gas passage 45 communicates with the discharge hole 47 of the lower block body 40c. Further, in the upper block body 40a, a large number of gas passages 44 are branched from the second gas introduction port 42. Gas passages 46 are formed in the middle block body 40b, and the gas passages 44 communicate with these gas passages 46. Further, the gas passage 46 is connected to a communication passage 46a extending horizontally in the middle block body 40b, and the communication passage 46a communicates with a large number of discharge holes 48 of the lower block body 40c. Then, the first and second gas introduction ports 41, 4
2 is connected to the gas line of the gas supply mechanism 50.

The gas supply mechanism 50 uses a cleaning gas.
A certain ClF_ThreeClF supplying gas _ThreeGas supply source 51,
TiCl, a Ti-containing gas_FourTiCl supplying gas
_FourGas supply source 52, N_TwoFirst N supplying gas_Twogas
Source 53 and second N_TwoGas supply source 55, NH_ThreeMoth
NH supplying gas_ThreeIt has a gas supply source 54. That
ClF_ThreeClF is used as the gas supply source 51._ThreeGas supply line
56 is TiCl_FourTiCl is used as the gas supply source 52._FourMoth
Supply line 57 is the first N_TwoThe gas source 53 has a
N of 1_TwoThe gas supply line 58 is NH_ThreeGas supply source 54
NH_ThreeThe gas supply line 59 is the second N_TwoGas supply
Source 53 has a second N_TwoEach gas supply line 60 is connected
Has been continued. And, for each gas supply line,
-Controller 62 and mass flow controller 62
Two valves 61 are provided with the valve interposed therebetween. The first
The gas inlet 41 of the_FourExtend from gas source 52
BiTiCl_FourThe gas supply line 57 is connected,
This TiCl_FourClF in the gas supply line 57_ThreeGas supply
ClF extending from source 51_ThreeGas supply line 56 and
First N_TwoFirst N extending from gas source 53_TwoGas supply
The supply line 58 is connected. Also, the second gas
NH at the inlet 42_ThreeNH extending from gas source 54_Three
The gas supply line 59 is connected to this NH_Threegas
The supply line 59 has a second N_TwoExtending from gas source 55
The second N_TwoThe gas supply line 60 is connected. Shi
Therefore, during the process, TiCl_FourGas source 52
From TiCl_FourGas is the first N_TwoFrom gas source 53
N_TwoTiCl with gas_FourVia gas supply line 57
Then, from the first gas inlet 41 of the shower head 40,
To the inside of the hour head 40, and through the gas passages 43 and 45.
While being discharged from the discharge hole 47 into the chamber 31, N
H_ThreeNH from gas source 54_ThreeGas is the second N _Twogas
N from source 55_TwoNH with gas_ThreeGas supply gas
The second gas guide of the showerhead 40 via the line 59.
From the inlet 42 to the inside of the shower head 40, the gas passage 4
Discharge from the discharge hole 48 into the chamber 31 through 4, 46
To be done. That is, the shower head 40 is made of TiCl_Four
Gas and NH_ThreeIn the chamber 31 completely independent of the gas
It is a matrix type supplied, these are
After ejection, they are mixed and a reaction occurs.

A high frequency power source 64 is connected to the shower head 40 via a matching unit 63, and high frequency power is supplied from the high frequency power source 64 to the shower head 40 as needed. Normally, this high frequency power supply 64 is not necessary, but if it is desired to increase the reactivity of the film forming reaction, the high frequency power supply 64 supplies high frequency power to the gas supplied into the chamber 31 via the shower head 40. It is also possible to form a film by converting into plasma.

A circular hole 65 is formed in the center of the bottom wall 31b of the chamber 31, and the bottom wall 31b is provided with an exhaust chamber 66 projecting downward so as to cover the hole 65. . An exhaust pipe 66 is connected to the side surface of the exhaust chamber 66, and an exhaust device 68 is connected to the exhaust pipe 67. By operating the exhaust device 68, the inside of the chamber 31 can be depressurized to a predetermined degree of vacuum.

The susceptor 32 is provided with three wafer support pins 69 (only two are shown) for supporting and raising and lowering the wafer W so as to project and retract with respect to the surface of the susceptor 32. 69 is fixed to the support plate 70. Then, the wafer support pin 69 is moved up and down via the support plate 70 by a drive mechanism 71 such as an air cylinder.

A side wall of the chamber 31 is provided with a loading / unloading port 72 for loading / unloading the wafer W to / from the transfer chamber 1, and a gate valve 73 for opening / closing the loading / unloading port 72.

Next, using such a TiN film forming apparatus, T
A film forming method for forming the iN film will be described with reference to FIGS. FIG. 4 is a flow chart for explaining the steps in forming the TiN film, and FIG. 5 is a schematic diagram showing the state inside the chamber 31 in the main steps.

First, the susceptor 32 is heated to about 500 to 700 ° C. by the heater 35, and the chamber 31 is cut off by the exhaust device 68 (STEP).
1), the gate valve 73 is opened (STEP 2), and as shown in FIG. 5A, the wafer W is transferred from the wafer transfer chamber 5 in the vacuum state via the loading / unloading port 72 by the blade 14a or 14b of the transfer device 12. Are carried into the chamber 31 (STEP 3). Next, as shown in FIG. 5B, the wafer W is placed on the wafer support pins 69 with the wafer support pins 69 protruding from the surface of the susceptor 32 (STEP 4). With the wafer W placed on the wafer support pins 69, the gate valve 73 is closed (STEP
5), subsequently, the N ₂ gas flowing through the TiCl ₄ gas supply line 57 and the NH ₃ gas supply line 59 is
As shown in FIG. 5C, the wafer W is introduced into the chamber 31 through the shower head 40, and the wafer W is subjected to first preliminary heating (STEP 6). In this case, the preferable flow rate range of the N ₂ gas is 1 to 10 L / for both the TiCl ₄ gas supply line 57 and the NH ₃ gas supply line 59.
It is min. In addition, the first preheating step is 5 to
A range of 30 seconds is preferred, for example 10 seconds.

After the completion of the first preheating step, the supply of N ₂ gas is stopped, the chamber 31 is again cut off (STEP 7), the wafer support pins 69 are lowered, and the state shown in FIG. ), The wafer W is transferred to the susceptor 3
Place on top of 2 (STEP 8). After that, N ₂ gas, N
The H ₃ gas is introduced into the chamber 31 by gradually increasing the flow rate until the inside of the chamber 31 reaches a predetermined pressure (STE
P9), this state is maintained for a predetermined time to perform the second preheating step (STEP 10). The preferable gas flow rate range at this time is that the N ₂ gas is the TiCl ₄ gas supply line 57.
And the NH ₃ gas supply line 59 is 1 to 10 L
/ A min, NH ₃ is 0.1~5L / min. Moreover, the preferable range of the pressure in the second preheating step is 100 to 1000 Pa, for example, 667 Pa.
Is set to. The second preheating step is preferably performed for 5 to 30 seconds, for example 10 seconds. In addition, the time for each of the three steps of STEPs 7 to 9 is preferably set to 10 seconds or less, and for example, set to 5 seconds each.

[0031] After the second preheating step is completed, while maintaining the flow rate of _{N 2} gas and NH ₃ gas in the same flow rate, Ti
Preflow is performed by introducing Cl ₄ gas into the chamber 31 at a flow rate of preferably 0.01 to 0.1 L / min (STEP 11). The pressure at this time is preferably 100
Is about 1000 Pa, for example 667 Pa, and is preferably carried out for 5 to 30 seconds, for example 10 seconds. Then, the TiN thin film forming step is carried out while keeping the gas flow rate and pressure the same (STEP 12). In this film forming step, a TiN film having a thickness of 5 to 100 nm is formed.
Since the film thickness is proportional to the film forming time, the film forming time is appropriately set according to the desired film thickness. That is, the film thickness at the time of film formation can be adjusted by the film formation time within the above range of 5 to 100 nm. For example, if the film thickness is 20 nm, 3
It is carried out for 5 seconds. The heating temperature of the substrate at this time is 400 to
The temperature is about 700 ° C, preferably about 600 ° C. At the time of this film formation, it is not always necessary to supply high-frequency power from the high-frequency power source 64 to turn the gas into plasma, but the gas may be turned into plasma with high-frequency power in order to enhance the reactivity. In this case, at a frequency of 450 kHz to 60 MHz, preferably 450 kHz to 13.56 MHz, 20
A high frequency power of 0 to 1000 W, preferably 200 to 500 W is supplied. In this case, the temperature of the wafer W is 300 to 700 ° C., preferably 40 because the gas reactivity is high.
It is about 0 to 600 ° C.

After the film forming process, NH ₃ gas and TiC are added.
The l ₄ gas is stopped, and the N ₂ gas is supplied as a purge gas through the TiCl ₄ gas supply line 57 and the NH ₃ gas supply line 59 at a flow rate of preferably 1 to 10 L / min to purge the chamber 31. (STE
P13). This purging step is preferably carried out for 5 to 30 seconds, for example 10 seconds.

Then, if necessary, N ₂ gas and N ₂
H ₃ gas is preferably flowed at a flow rate in the range of 1 to 10 L / min to perform the nitride treatment on the surface of the formed TiN thin film (STEP 14). The pressure in the chamber at this time is preferably 100 to 1000 Pa, for example 6
67 Pa, and the time is preferably 5 to 180 seconds, for example 25 seconds. The supply of N ₂ gas at this time is the first
From the N ₂ gas supply source 53 to the TiCl ₄ gas supply line 5
7, or the second N ₂ gas supply source 55
To NH ₃ gas supply line 59, or both of them may be used.

After the lapse of a predetermined time, the N ₂ gas and the NH ₃ gas are gradually stopped (STEP 15), and the film forming process is terminated when the supply of these gases is completely stopped (STEP 16).

Thereafter, the wafer support pins 69 are raised to lift the wafer W, the gate valve 73 is opened, and the blade 14a or 14b of the transfer device 12 is moved to the chamber 31.
The wafer W is mounted on the blade 14a or 14b by lowering the wafer support pin 69, and is unloaded to the wafer transfer chamber 5 (STEP 17).

[0036] After this manner predetermined number deposition, the chamber 31 is cleaned by supplying ClF ₃ gas from ClF ₃ gas supply source 51.

In the conventional method, the wafer W is placed on the susceptor 32.
Although the gas was introduced into the chamber and pre-heat treatment was performed after the wafer W was mounted on the wafer W, the wafer W is rapidly heated, so that a warp occurs in the case of a 300 mm wafer. On the other hand, in the present embodiment, the N ₂ gas is introduced into the chamber 31 in a state where the wafer W is first placed on the wafer support pins 69 protruding above the susceptor 32, and the first preliminary heat treatment (STEP 6). ) Is not performed rapidly, but the second heating process on the susceptor 32 is performed after being heated to a certain degree, so that the thermal stress exerted on the wafer W is relaxed, and the wafer W is as large as 300 mm. Even a thing can be prevented from warping.

After completion of the first preheating step, S
Prior to the step of placing the wafer W of the TEP 8 on the susceptor 32, in step 7, the supply of N ₂ gas is stopped and the inside of the chamber 31 is cut off, so that when the wafer W is lowered, the wafer W is lowered by the resistance of the gas. Are prevented from slipping on the wafer support pins 69. Furthermore, STEP
In FIG. 9, N ₂ gas and NH ₃ gas are gradually increased in flow rate and introduced into the chamber 31 until the gas pressure of the second preheating (STEP 10) is reached. It is avoided that W is affected.

Next, the result of actually confirming the effect of the method of the present invention will be described. Here, from the first preheating step (STEP 6) to the second preheating step (STE).
The gas flow rate, gas pressure, and time up to P10) were set as shown in FIG. That is, in the first preheating step (STEP 6), N ₂ gas is flowed at a flow rate of 1.8 L / min in the TiCl ₄ gas supply line 57 and 1.8 L / min in the NH ₃ gas supply line 59, and is supplied for 10 seconds. After that, STEP 7 to STEP 9 are performed for 5 seconds each, and the N ₂ gas flow rate in the _second preheating step (STEP 10) is 1.8 in the TiCl ₄ gas supply line 57.
L / min, 3.7 L / m in NH ₃ gas supply line 59
In, the NH ₃ gas flow rate was 0.225 L / min, and the pressure was 667 Pa for 30 seconds. afterwards,
After TiCl ₄ gas was added at a flow rate of 0.045 L / min and pre-flow was performed for 10 seconds (STEP 11), film formation was performed for 35 seconds at the same gas flow rate (STEP 1).
2). The pressure during film formation was 667 Pa. As a result of forming the TiN film on the large-diameter 300 mm wafer in this way, there was no wafer warpage.

The present invention can be variously modified without being limited to the above embodiment. For example, although the TiN film is formed in the above embodiment, the present invention is not limited to this, and Ti, Al, W formed by heating may be formed.
It is also effective when forming a film of another material such as. Further, in the above-described embodiment, N ₂ gas is used in the first preheating and N ₂ gas and NH ₃ are used in the _second preheating, but the present invention is not limited to this. Furthermore, in the above-described embodiment, the gas is introduced during the first preheating and the second preheating, but a certain effect can be obtained without supplying the gas. However, the effect is greater when gas is introduced. Furthermore, in the above embodiment, the substrate to be processed is not limited to a semiconductor wafer, and may be another substrate such as a liquid crystal display (LCD) substrate.
Other layers may be formed on the substrate.

[0041]

As described above, according to the present invention,
Prior to the preheating performed by placing the substrate to be processed on the mounting table, the substrate supporting pins of the mounting table are raised in the processing chamber to perform the preheating while the substrate to be processed is held on the substrate supporting pins. Therefore, the substrate to be processed is not heated abruptly as in the case where the substrate to be processed is immediately placed on a heated mounting table, the thermal stress of the substrate to be processed is relaxed, and the substrate to be processed is large. Even in this case, the warp can be prevented from occurring.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a multi-chamber type film forming system equipped with a TiN film forming apparatus for carrying out the method of the present invention.

FIG. 2 is a sectional view showing a contact hole portion of a semiconductor device using a TiN film as a barrier layer.

FIG. 3 is a TiN carrying out a CVD film forming method according to the present invention.
Sectional drawing which shows a film-forming apparatus.

FIG. 4 is a flowchart for explaining a process for forming a TiN film.

FIG. 5 is a schematic view showing a state inside the chamber in main steps.

FIG. 6 is a graph showing the gas flow rate, gas pressure, and time from the first preheating step to the second preheating step in the experiment in which the effect of the method of the present invention was confirmed.

[Explanation of symbols]

3,4 ... TiN film forming equipment 31 ... Chamber 32 ... Susceptor 35: heater 40 ... Shower head 50 ... Gas supply mechanism 69 ... Wafer support pin W: Semiconductor wafer

Continued front page    F-term (reference) 4K030 AA03 AA13 BA38 CA04 DA02                       FA10 LA15                 4M104 BB14 BB30 CC01 DD43 DD44                       DD45 FF22 HH20                 5F033 HH08 HH18 HH19 HH33 JJ08                       JJ18 JJ19 JJ33 KK01 MM05                       MM13 NN06 NN07 PP03 PP06                       XX00 XX19

Claims (6)

[Claims] 1. A substrate to be processed is placed on a mounting table in a processing chamber, and a thin film is formed on the substrate to be processed by CVD while heating the substrate to be processed by the heating means via the mounting table.
A VD film forming method, wherein a substrate supporting pin of a mounting table is raised in a processing chamber to hold the substrate to be processed on the substrate supporting pin, and the first substrate is heated by the heating unit. Second preheating for lowering the substrate support pins to place the substrate to be processed on the mounting table and preheating the substrate to be processed, and thereafter to the substrate to be processed. A CVD film forming method characterized by forming a film. 2. The CVD film forming method according to claim 1, wherein the first preheating and the second preheating are performed while introducing gas into the chamber. 3. A substrate to be processed is placed on a mounting table in a processing chamber, and a thin film is formed on the substrate to be processed by CVD while heating the processing substrate via the mounting table by a heating means.
A VD film forming method, comprising: loading a substrate to be processed into a chamber, raising a substrate support pin of a mounting table to receive the substrate to be processed, and holding the substrate to be processed on the substrate support pin. In the state where the heating means is used to heat the mounting table, a step of introducing gas into the chamber that is evacuated and performing a first preliminary heating process; Stopping the introduction, lowering the substrate support pins to place the substrate to be processed on the mounting table, and introducing a gas into the chamber while the substrate to be processed is mounted on the mounting table. 2. A CVD film forming method comprising: a step of performing preheating 2 and a step of forming a film on a substrate to be processed thereafter. 4. The method further comprising the step of gradually increasing the gas pressure in the chamber while the substrate to be processed is placed on the mounting table prior to the step of performing the second preheating. The CVD film forming method according to claim 3. 5. A CVD method in which a substrate to be processed is placed on a mounting table in a processing chamber, and a TiN thin film is formed on the substrate to be processed by CVD while heating the substrate to be processed by a heating means provided on the mounting table. In the film method, the step of loading the substrate to be processed into the chamber, raising the substrate support pins of the mounting table to receive the substrate to be processed thereon, and the state of holding the substrate to be processed on the substrate support pins. And a step of introducing an inert gas into the chamber that is being evacuated while heating the mounting table by the heating means to perform a first preheating treatment; and being inert while the chamber is evacuated. Stopping the introduction of gas, lowering the substrate support pin to place the substrate to be processed on the mounting table, and an inert gas in the chamber while the substrate to be processed is mounted on the mounting table. A step of introducing a reaction gas containing an element to carry out a second preliminary heating; and a step of introducing a reaction gas further containing Ti into the chamber to form a TiN film on the substrate to be processed. A CVD film forming method comprising: 6. Prior to the step of performing the second preheating, an inert gas and nitrogen are introduced into the chamber while the substrate to be processed is placed on the placing table so that the gas pressure gradually rises. The CVD film forming method according to claim 5, further comprising a step of introducing.