JP2001144032A - TiSiN thin film and method for forming the same, semiconductor device and method for manufacturing the same, and apparatus for forming TiSiN thin film - Google Patents

Abstract

[PROBLEMS] To provide a TiSiN thin film which can be formed with high step coverage and a method of manufacturing the same. SOLUTION: Ti-containing gas, Si-containing gas, and N
TiS by thermal CVD using film forming gas containing gas
An iN thin film is formed, and TiCl is used as the Ti-containing gas.
₄ , at least one of tetraxydimethylaminotitanium and tetraxydiethylaminotitanium,
As i-containing gas, SiH ₂ Cl ₂ , SiHCl ₃ , S
At least one of iCl ₄ , Si ₂ H ₄ , and Si ₂ H ₆ is used, and at least one of NH ₃ and monomethylhydrazine is used as the N-containing gas.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a TiSiN thin film used as, for example, a barrier layer in a semiconductor device, a method of forming the same, a semiconductor device using the same, a method of manufacturing the same, and a TiSiN thin film forming apparatus.

[0002]

2. Description of the Related Art In the manufacture of semiconductor devices, in response to recent demands for higher density and higher integration, for example,
As a capacitor of a RAM memory part, a capacitor using (Ba, Sr) TiO ₃ (BST) having a high dielectric constant and a low leak current density as an insulating layer and a platinum (Pt) electrode having a low leak current density as an electrode layer is used. Proposed (IE
DM 97-249).

In this type of capacitor, when the lower electrode layer comes into contact with the underlying poly-Si plug, a reaction occurs between the two and a barrier layer is conventionally provided between the Si plug and the lower electrode layer of the capacitor. Is provided.
Conventionally, TiN has been used as such a barrier layer, but there is a problem that the barrier layer is oxidized when the insulating layer, which is an oxide, is formed. For this reason, in the above-mentioned document, a TiSiN thin film having less barrier to oxidation and high barrier properties is used as a barrier layer.

[0004]

By the way, this type of capacitor often has a bent structure from the viewpoint of increasing the capacitance. However, from the viewpoint of miniaturization, the barrier layer formed on such a portion has High step coverage is required. However, in the above document, TiSiN
The membrane is PVD (Physical Vapor Depo)
However, there is a problem that it is difficult to form a TiSiN thin film with a high step coverage because the film is formed by the D.I.

[0005] Further, the TiSiN thin film has various barrier applications such as a barrier layer in a contact hole or a via hole because of its excellent barrier property. It is required to form a TiSiN thin film with high step coverage.

[0006] The present invention has been made in view of the above circumstances, and a TiSiN thin film capable of being formed with high step coverage, a method of forming the same, a semiconductor device using the same, a method of manufacturing the same, and a TiSiN film. It is an object of the present invention to provide a thin film forming apparatus.

[0007]

As a result of repeated investigations to solve the above-mentioned problems, the present inventors have found that TiSiN
It has been found that by forming a thin film, film formation with high step coverage can be realized without causing inconvenience.

In general, this kind of barrier layer is formed by PVD as described in the above-mentioned literature, but recently, CVD (Che) has been used as a technique capable of responding to further miniaturization.
(Metal Vapor Deposition) has begun to be used, and the formation of a TiSiN thin film by CVD is being studied. However, since thermal CVD has a high film formation temperature, the film formation by plasma CVD at a lower film formation temperature has been aimed at. I have. However, if a TiSiN thin film is formed by plasma CVD, the step coverage is not sufficient. Therefore, when further investigation was made, the thermal CV
It has been found that even if a TiSiN thin film is formed by D, a high step coverage can be obtained without inconvenience due to a high film forming temperature, and the present invention has been completed.

That is, the first invention provides a TiSiN thin film characterized by being formed by thermal CVD.

In a second aspect of the present invention, the present invention relates to a Ti-containing gas,
An object of the present invention is to provide a method for forming a TiSiN thin film, wherein a TiSiN thin film is formed by thermal CVD using a film forming gas containing an i-containing gas and a N-containing gas.

In the above method for forming a TiSiN thin film,
As the Ti-containing gas, TiCl ₄, Tetraxydim
Tylaminotitanium, tetraxydiethylaminotitanium
At least one of the metals can be used. Also,
As the Si-containing gas, SiH₂Cl₂, SiHCl
₃, SiCl₄, Si₂H₄, Si₂H₆At least
One type can be used. Further, the N-containing gas and
And NH₃And at least one of monomethylhydrazine
One type can be used.

According to a third aspect of the present invention, there is provided an insulating layer made of a high dielectric constant material, a lower electrode layer provided thereunder, an upper electrode layer provided on the insulating layer, the insulating layer and the lower electrode layer. And a capacitor portion having a barrier layer provided between the first and second electrodes, wherein the upper electrode layer is formed of TiS formed by thermal CVD.
A semiconductor device characterized by being an iN thin film is provided.

According to a fourth aspect of the present invention, there is provided an insulating layer made of a high dielectric constant material, a lower electrode layer provided thereunder, an upper electrode layer provided on the insulating layer, the insulating layer and the lower electrode layer. And a capacitor section having a barrier layer provided between the first and second layers, wherein the barrier layer is formed of TiSi formed by thermal CVD.
A semiconductor device characterized by being an N thin film is provided.

According to a fifth aspect of the present invention, there is provided an insulating layer made of a high dielectric constant material, a lower electrode layer provided thereunder, an upper electrode layer provided on the insulating layer, the lower electrode layer and a lower layer thereof. And a barrier portion provided between the first and second wiring layers, wherein the barrier layer is a TiSiN thin film formed by thermal CVD.

In a fifth aspect, at least one of the upper electrode layer and the lower electrode layer can be formed of Pt or Ru. In addition, the upper electrode layer is a thermal CV
D may be a TiSiN thin film. Further, a barrier layer composed of a TiSiN thin film formed by thermal CVD can be formed on the upper electrode layer.

According to a sixth aspect of the present invention, an insulating layer made of a high dielectric constant material, a lower electrode layer provided thereunder, an upper electrode layer provided on the insulating layer, the lower electrode layer and a lower layer A capacitor portion having a barrier layer provided between the upper electrode layer and the lower electrode layer.
A semiconductor device characterized by being a TiSiN thin film formed by VD.

In the third to sixth aspects, the high dielectric constant material is (Ba, Sr) TiO ₃ , Pb (Z
(r, Ti) It is preferably selected from O ₃ , Ta ₂ O ₅ , and RuO.

According to a seventh aspect of the present invention, there is provided a wiring layer, a buried wiring portion for connecting the wiring layer to the semiconductor substrate or a conductive layer thereon, and a wiring layer provided between the buried wiring portion and the semiconductor substrate or a conductive layer thereon. And a barrier layer, wherein the barrier layer is a TiSiN thin film formed by thermal CVD.

An eighth invention comprises a gate electrode formed on a main surface of a semiconductor substrate via an insulating layer and connected to a wiring layer, wherein the gate electrode is made of Ti formed by thermal CVD.
A semiconductor device having a SiN thin film is provided.

In the eighth invention, the gate electrode may have a structure having a lower layer made of a TiSiN thin film formed by thermal CVD and an upper layer made of W formed thereon. The gate electrode is formed on a semiconductor substrate, and is composed of Ba, Sr) TiO ₃ , Pb (Z
(r, Ti) an insulating layer made of a material selected from O ₃ , Ta ₂ O ₅ , and RuO, a conductive layer thereon, and TiSi formed between the insulating layer and the conductive layer by thermal CVD.
A structure having a barrier layer made of an N thin film can be employed. In this case, a SiO _x N _y thin film can be provided between the semiconductor substrate and the insulating layer.

According to a ninth aspect, a step of forming a lower electrode layer, a step of forming a barrier layer on the lower electrode layer, a step of forming an insulating layer made of a high dielectric constant material on the barrier layer, Forming a capacitor portion by the step of forming an upper electrode layer on the insulating layer, wherein the barrier layer comprises a Ti-containing gas,
Provided is a method for manufacturing a semiconductor device, which is obtained by forming a TiSiN thin film by thermal CVD using a film forming gas containing a Si-containing gas and a N-containing gas.

According to a tenth aspect, a step of forming a lower electrode layer, a step of forming a barrier layer on the lower electrode layer, a step of forming an insulating layer made of a high dielectric constant material on the barrier layer, Forming a capacitor portion by the step of forming an upper electrode layer on the insulating layer, wherein the upper electrode layer is formed of TiSiN by thermal CVD using a deposition gas containing a Ti-containing gas, a Si-containing gas, and a N-containing gas. A method for manufacturing a semiconductor device, which is obtained by forming a thin film, is provided.

According to an eleventh aspect, a step of forming a barrier layer on a wiring layer formed on a semiconductor substrate, a step of forming a lower electrode layer on the barrier layer, and a step of forming a high dielectric layer on the lower electrode layer Forming a capacitor portion by a step of forming an insulating layer made of a dielectric material and a step of forming an upper electrode layer on the insulating layer, wherein the barrier layer contains a Ti-containing gas, a Si-containing gas, and an N-containing gas. Provided is a method for manufacturing a semiconductor device, which is obtained by forming a TiSiN thin film by thermal CVD using a film forming gas.

According to a twelfth aspect, a step of forming a barrier layer on a wiring layer formed on a semiconductor substrate, a step of forming a lower electrode layer on the barrier layer, and a step of forming a high dielectric layer on the lower electrode layer Forming a capacitor portion by a step of forming an insulating layer made of a dielectric material and a step of forming an upper electrode layer on the insulating layer, wherein the barrier layer and the upper electrode layer include a Ti-containing gas, a Si-containing gas, Provided is a method for manufacturing a semiconductor device, which is obtained by forming a TiSiN thin film by thermal CVD using a film forming gas containing an N-containing gas.

According to a thirteenth aspect, a step of forming a lower electrode layer on a wiring layer formed on a semiconductor substrate, a step of forming an insulating layer made of a high dielectric constant material on the lower electrode layer, Forming a capacitor portion by forming an upper electrode layer on the upper electrode layer, and forming the lower electrode layer and the upper electrode layer by using a deposition gas containing a Ti-containing gas, a Si-containing gas, and an N-containing gas. Provided is a method for manufacturing a semiconductor device, which is obtained by forming a TiSiN thin film by CVD.

According to a fourteenth aspect, a step of forming an insulating layer on a semiconductor substrate or a conductive layer thereon, a step of forming a contact hole or a via hole in the insulating layer by etching, A step of forming a barrier layer in a contact hole or a via hole and a step of forming a wiring layer on the barrier layer to form a buried wiring portion, wherein the barrier layer comprises a Ti-containing gas,
Provided is a method for manufacturing a semiconductor device, which is obtained by forming a TiSiN thin film by thermal CVD using a film forming gas containing a Si-containing gas and a N-containing gas.

According to a fifteenth aspect, a gate electrode is formed by a step of forming a lower layer made of a TiSiN thin film on a semiconductor substrate via an insulating layer, and a step of forming an upper layer made of W on the lower layer. A method for manufacturing a semiconductor device, wherein a lower layer made of a TiSiN thin film is formed by thermal CVD using a deposition gas containing a Ti-containing gas, a Si-containing gas, and an N-containing gas.

According to a sixteenth aspect, a step of forming an insulating layer made of a high dielectric constant material on a semiconductor substrate, a step of forming a barrier layer on the insulating layer, and a step of forming a conductive layer on the barrier layer Forming a gate electrode, and the barrier layer is obtained by depositing a TiSiN thin film by thermal CVD using a deposition gas containing a Ti-containing gas, a Si-containing gas, and a N-containing gas. A method for manufacturing a semiconductor device is provided.

[0029] In the sixteenth aspect, the method may further include forming a SiO _x N _y thin film between the semiconductor substrate and the insulating layer.

According to a seventeenth aspect, a chamber for accommodating a substrate to be processed, a support member for supporting the substrate to be processed in the chamber, a film formation gas introducing mechanism for introducing a film formation gas into the chamber, A heating mechanism for heating the supported substrate to be processed, wherein the film-forming gas introduction mechanism comprises Ti
Forming a TiSiN thin film on a substrate to be processed heated by the heating mechanism and forming a TiSiN thin film on the substrate by thermal CVD on the substrate heated by the heating mechanism. A membrane device is provided.

[0031]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 shows a thermal CVD for forming a thermal CVD-TiSiN thin film according to the present invention.
It is sectional drawing which shows an apparatus. The thermal CVD apparatus 10 has an airtight, substantially cylindrical chamber 11 in which a susceptor 12 for horizontally supporting a semiconductor wafer W, which is an object to be processed, has a cylindrical support. Member 13
It is arranged in a state supported by. Susceptor 1
A guide ring 14 for guiding the semiconductor wafer W is provided at the outer edge of the second. Also, the susceptor 12
Has a heater 15 embedded therein.
5 is heated from a power supply 16 to heat the semiconductor wafer W as a processing target to a predetermined temperature. A controller 17 is connected to the power supply 16, whereby the output of the heater 15 is controlled according to a signal from a temperature sensor (not shown).

A shower head 20 is provided on a top wall 11 a of the chamber 11.
A gas for film formation is introduced from 0 to the chamber 11.

As a film forming gas, a Ti-containing gas and a Si-containing gas are used.
A gas and a N-containing gas are used. Ti-containing gas
The TiCl₄, Tetraxydimethylaminotitanium
(TDMAT), tetraxydiethylaminotitanium
(TDEAT) is exemplified. As the Si-containing gas,
SiH₂Cl₂, SiHCl₃, SiCl₄, Si
H ₄, Si₂H₆And the N-containing gas is N
H₃, Monomethylhydrazine (MMH).
In FIG. 1, TiCl is used as the Ti-containing gas.₄, Si containing gas
SiH₂Cl₂, N-containing gas as NH₃For
In the following, the case where these gases are used is shown.
The case will be described.

The shower head 20 has a susceptor 1
Numerous gas discharge holes 20 for discharging gas toward
a and 20b are formed alternately. A pipe of a gas supply mechanism 30 is connected to the shower head 20, and TiCl is supplied to a gas discharge hole 20a as described later.
A pipe 45 for supplying _four gases is connected, and a pipe 46 for supplying NH ₃ gas is connected to the gas discharge holes 20 b, and a predetermined gas is introduced into the chamber 11 via the shower head 20. It has become. As described above, the shower head 20 is of a matrix type, in which TiCl ₄ gas, NH ₃ gas and SiH
A post-mix method is adopted in which ₂ Cl ₂ is discharged from different discharge holes alternately formed and mixed after the discharge.

The gas supply mechanism 30 uses a cleaning gas.
Some ClF₃Supplying ClF₃Source 31, N₂Provide
N to feed₂Source 32, TiCl₄Supplying TiCl
₄Source 33, SiH₂Cl₂Supplying SiH₂Cl
₂Source 34, NH as N-containing gas₃Supply
NH₃It has a supply source 35. And ClF ₃
A gas line 39 is connected to the supply source 31.₂Source 32
Gas line 40 is made of TiCl₄The gas source is
41 is SiH₂Cl₂Gas line 4
2 is NH₃A gas line 43 is provided for the supply source 35, respectively.
It is connected. Each line has a valve 47 and
And a mass flow controller 48.

N₂Gas line 40 extending from source 32
Contains TiCl₄Gas line 41 extending from supply source 33
Merged and passed through the gas line 40 and the pipe 45.
And N ₂TiCl carried in gas₄Gas shower
The head 1 reaches the chamber 20 through the gas discharge holes 20a.
1 is introduced. ClF₃Gas extending from source 31
The line 39 joins the gas line 40 and the gas line 40
By opening the valve provided on the
ClF which is a fining gas₃Are gas lines 39, 40 and
To the shower head 20 through the pipe 45
It is introduced into the chamber 11 from the outlet 20a. Also,
NH₃The gas is NH₃From the source 35 to the gas line 43
To the shower head 20 through the pipe 46 and the gas.
It is introduced into the chamber 11 through the discharge hole 20b. SiH
₂Cl₂The gas line 42 connected to the supply source 34
Line 41₂Cl₂Gas rye
, Gas line 41, gas line 40 and pipe 4
5 to the shower head 20 and the gas discharge holes 20
a is introduced into the chamber 11. In addition, carrier
N as gas₂May be used instead of Ar.

An exhaust pipe 18 is connected to the bottom wall 11b of the chamber 11, and an exhaust device 19 including a vacuum pump is connected to the exhaust pipe. And the exhaust device 19
The pressure in the chamber 11 can be reduced to a predetermined degree of vacuum by operating.

Next, an example of a method for forming a TiSiN thin film on a semiconductor wafer W by using such an apparatus will be described. First, charged with the semiconductor wafer W into the chamber 11, exhaust system 19 while heating the wafer W by evacuating the chamber 11 to the chamber 11 to a high vacuum state by the heater 15, subsequently, N ₂ gas and NH ₃ gases are introduced into the chamber 11 at a predetermined flow rate ratio, and the inside of the chamber 11 is, for example, 133.3 to 1333.2 Pa (1 to 1).
0 Torr) and perform pre-annealing.

Next, the inside of the chamber 11 is provided with a place for film formation.
To a constant pressure, N₂Gas and NH ₃Maintain gas flow
TiCl₄Gas and SiH₂Cl₂Predetermined
Preflow for 5 to 20 seconds at the flow rate ratio,
A TiSiN thin film is formed for a predetermined time under the same conditions as the flow.
U.

Preferred examples of the film forming conditions at this time are as follows. Film forming pressure: 40.0 to 666.6 Pa (0.3 to 5 Torr)
r) Temperature: 450 to 650 ° C. Flow rate: TiCl ₄ 1.2 × 10 −3 to 3.0 × 1
_{0-3m3 / sec (20~50sccm) NH 3} 6.0 × 10-3~3.0 × 10-2m3 / s
ec (100 to 500 sccm) SiH ₂ Cl ₂ 6.0 × 10 −3 to 3.0 × 10 −2
m3 / sec (100-500sccm)

In this manner, TiSi is formed by thermal CVD.
By forming an N thin film on a portion having irregularities, good step coverage can be obtained. That is, when the film is formed by thermal CVD, unlike the case of plasma CVD, the step reaction can be essentially increased because of the surface reaction. Therefore, the film thickness can be reduced, which can contribute to miniaturization of the device.

As shown in FIG. 2, when the hole portion H exists as shown in FIG. 2, the film thickness at the portion other than the hole portion H is A, the film thickness at the bottom of the hole is B, Assuming that the film thickness at the side of the hole is C, the film is evaluated by the bottom coverage B / A and the side coverage C / A.

Specifically, for example, when a TiSiN thin film is formed by thermal CVD according to the present embodiment in a hole having a width of about 0.1 to 0.2 μm and a depth of about 0.5 μm as shown in FIG. , Both bottom coverage and side coverage were over 90%. On the other hand, in the case of plasma CVD, these values were inadequate values of 20 to 30%. When a TiSiN thin film is formed by thermal CVD according to the present embodiment, the plasma CV
Although the film formation temperature was higher than in the case of D, it was found that the film could be formed with good film quality.

After the TiSiN thin film is formed as described above,
The semiconductor wafer is carried out of the chamber 11, and a cleaning gas ClF ₃ gas is introduced into the chamber 11 to clean the inside of the chamber.

Next, TiS by thermal CVD according to the present invention is used.
An application example of the iN thin film will be described. In any of the following application examples, the thermal CVD-TiSiN thin film can be formed as described above.

FIG. 3 is a view showing a Ti film formed by thermal CVD according to the present invention.
An SiN thin film is formed on a MIS (Metal Isolation Si) such as a DRAM.
FIG. 3 is a cross-sectional view showing an example used for a (icon) type capacitor structure. A lower electrode layer 51 made of amorphous Si is connected to the impurity diffusion region 50a of the Si substrate 50.
On the lower electrode layer 51, RTN (Rapi)
d Thermal Nitrization)
BST, Pb (Zr, Ti) O via N barrier layer 52
_{3 (PZT), Ta 2 O} 5 or the insulating layer 53 made of a high dielectric constant material RuO is formed, the upper electrode layer 54 consisting of thermal CVD-TiSiN film of the present invention thereon is formed. Then, a metal wiring layer (not shown) is formed on the upper electrode layer 54. Conventionally, a TiN film has been used as the upper electrode layer 54, but O of Ta ₂ O ₅ diffuses into the TiN film by a heat treatment in a later process, so that the TN film is formed.
iO, and as a result, the thickness of the TiN film is reduced and Ta
There is a problem that the film thickness of ₂ O ₅ is increased and the capacity is reduced. On the other hand, such a problem can be solved by using the upper electrode layer 54 made of the TiSiN thin film of the present invention. Also, as described above, thermal CVD
Since the -TiSiN thin film has good step coverage, the thickness can be reduced, which contributes to miniaturization of a semiconductor device including such a capacitor structure.

FIG. 4 has the same basic structure as FIG. 3, but
Instead of the SiN barrier layer 52 on the lower electrode layer 51,
A barrier layer 55 made of the TiSiN thin film of the present invention is formed. Thereby, the barrier property between the lower electrode layer 51 and the insulating layer 53 can be further enhanced. As described above, since the upper electrode layer 54 and the barrier layer 55 are formed of a thermal CVD-TiSiN thin film having good step coverage, the thickness can be reduced, which contributes to miniaturization of a semiconductor device.

FIG. 5 is a view showing a Ti film formed by thermal CVD according to the present invention.
A SiN thin film is formed on a MIM (Metal Isolation Mesh) such as a DRAM.
FIG. 3 is a cross-sectional view showing an example used for a (tal) type capacitor structure. On the poly-Si plug 61 connected to the impurity diffusion region of the Si substrate, the thermal CVD-TiSiN according to the present invention is provided.
A barrier layer 62 made of a thin film is formed. On the barrier layer 62, a lower electrode layer 6 made of Pt, Ru or the like is formed.
3, BST, Pb (Zr, Ti) O ₃ (PZT), Ta
Insulating layer 6 made of high dielectric constant material of ₂ O ₅ or RuO
4, and an upper electrode layer 65 made of Pt, Ru or the like is formed in this order.

In such a structure, by using the above-mentioned high dielectric constant material as the insulating layer 64, it is possible to obtain a large capacity as a capacitor of the DRAM memory portion, to reduce the leak current density, Pt and Ru used as materials can also reduce the leak current density, which contributes to higher density and higher integration of semiconductor devices. Further, since the electrodes are made of metal such as Pt and Ru instead of Si, the speed can be increased. Further, the thermal CVD-TiS according to the present invention
Since the barrier layer 52 is formed of the iN thin film, the reaction between the lower electrode layer 53 and the poly-Si plug 61 thereunder can be effectively prevented, and the barrier layer 52 can be formed when the insulating layer 64 is formed. Is not easily oxidized. Further, as described above, the thermal CVD-TiSiN thin film has a good step coverage, so that the film thickness can be reduced, which also contributes to miniaturization of a semiconductor device including a capacitor structure.

FIG. 6 shows an MIM type capacitor structure in which an upper electrode layer 66 made of thermal CVD-TiSiN of the present invention is formed instead of the upper electrode layer 65 made of Pt, Ru, etc. of FIG. FIG. 7 shows the thermal CVD-TiSiN of the present invention instead of forming the upper electrode layer 66 and replacing the lower electrode layer 63 made of Pt, Ru or the like in FIG.
The lower electrode layer 67 made of In any case, thermal CVD-TiSi with good step coverage
Since N is used as an electrode material, it contributes to further miniaturization of a semiconductor device including a capacitor structure. In particular, FIG.
In the case of (1), since the lower electrode layer is made of thermal CVD-TiSiN having a good barrier property, the barrier layer 62 becomes unnecessary and further miniaturization can be achieved.

In the case of the structure shown in FIG. 5, in order to reliably prevent a reaction between the upper electrode layer 65 and a wiring layer (not shown) thereover, as shown in FIG. Electrode layer 6
A barrier layer 68 made of the thermal CVD-TiSiN of the present invention may be formed on 5.

FIG. 9 shows a thermal CVD-TiSi according to the present invention.
FIG. 4 is a cross-sectional view showing an example in which an N thin film is used for a contact portion of a metal wiring layer. An interlayer insulating film 71 is formed on a Si substrate 70, and a contact hole 72 reaching the impurity diffusion region 70a of the Si substrate 70 is formed in the interlayer insulating film 71. Interlayer insulating film 71 and contact hole 72
Is formed with a barrier layer 73 made of a thermal CVD-TiSiN thin film according to the present invention. A metal wiring layer 74 made of W is formed on the barrier layer 73. The metal wiring layer 74 made of W is formed in the contact hole 72.
The buried wiring portion 74a is also filled therein, and the buried wiring portion 74a electrically connects the impurity diffusion region 70a of the Si substrate 70 to the metal wiring layer 74. Ti
Since the SiN thin film has a higher barrier property than the conventional TiN thin film, its presence causes the W of the metal wiring layer 74 and the underlying Si
The formation of a compound due to the reaction with is extremely effectively prevented. Further, as described above, thermal CVD-TiSiN
Since the thin film has good step coverage, the thickness can be reduced, which contributes to miniaturization of a semiconductor device including such a contact portion. The thermal CVD according to the present invention
Can be used as a barrier layer for other wiring layers such as Cu and Al. Also, the metal wiring layer 7
4 can also be applied to the connection between the wiring layer and the wiring layer on the substrate.

FIG. 10 shows a thermal CVD-TiS according to the present invention.
An example in which an iN thin film is used for a gate electrode will be described. A gate electrode 84 including a lower layer 82 formed of a thermal CVD-TiSiN thin film and an upper layer 83 formed of a W thin film thereon is provided on a Si substrate with an insulating film 81 interposed therebetween.
On the upper layer 83, a W wiring layer 83a is formed. Reference numeral 85 indicates a spacer made of SiN. The TiSiN thin film used as a gate electrode has low resistance, excellent barrier properties, and is thermally stable, and thus exhibits excellent characteristics as a gate electrode. Further, since the thermal CVD-TiSiN thin film has good step coverage, the thickness of the lower layer 82 can be reduced,
The gate size can be reduced.

FIG. 11 shows that a BST,
An insulating layer 86 made of a high-permittivity material such as Pb (Zr, Ti) O ₃ (PZT), Ta ₂ O _5, or RuO is formed, and a thermal CVD-TiSiN thin film according to the present invention is formed thereon. 87, and an upper layer 88 made of an Al or W thin film is further formed thereon to form a gate electrode 89.
And In FIG. 11, 90 and 91 are a source and a drain, respectively. FIG. 12 shows that a SiO ₂ film is formed on a Si substrate 80 and the surface thereof is nitrided to form SiO _x N
_y thin film 92 is formed, and BST, Pb (Zr, T
i) An insulating layer 93 made of a high dielectric constant material of O ₃ (PZT), Ta ₂ O _5, or RuO is formed, and a barrier layer 9 made of a thermal CVD-TiSiN thin film according to the present invention is formed thereon.
4 is formed thereon, and an upper layer 95 made of a W or Al thin film is further formed thereon to form a gate electrode 96. All of these are structures that can cope with high speed, and thermal CV
Barrier layers 87 and 94 made of D-TiSiN thin film
Are the upper layers 88 and 95 and the insulating layer 8 made of a high dielectric constant material.
6,93 can be effectively prevented. In addition, since the thermal CVD-TiSiN thin film has good step coverage, the thickness of the barrier layers 87 and 94 can be reduced. In the case of FIG. 11, S
Since the insulating layer 86 is brought into direct contact with the i-substrate 80, interface control may be difficult in some cases. In that case,
As shown in FIG. 12, after forming a SiO ₂ film between the Si substrate 80 and the insulating layer 93, the surface thereof is nitrided SiO _x.
By providing the _Ny thin film 92, such inconvenience can be solved.

The present invention can be variously modified without being limited to the above embodiment. For example, the above manufacturing conditions are merely examples, and the conditions may be set appropriately according to the process. Further, the substrate to be used is not limited to a semiconductor wafer, and may be another substrate, or a substrate having another layer formed on the surface.

[0056]

As described above, according to the present invention,
Since the TiSiN thin film is formed by thermal CVD, the film can be formed with high step coverage without causing any inconvenience. The thermal CVD-TiSiN thin film of the present invention is suitable as a barrier layer or an electrode in a capacitor structure of a DRAM or the like, a barrier layer in a contact portion of a metal wiring layer, or an electrode material or a barrier layer in a gate electrode portion.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically showing a thermal CVD apparatus applied to forming a thermal CVD-TiSiN thin film according to the present invention.

FIG. 2 is a schematic diagram for explaining a step coverage evaluation method.

FIG. 3 shows a thermal CVD-TiSiN thin film according to the present invention,
Sectional drawing which shows the example used for the capacitor structure, such as AM.

FIG. 4 shows a thermal CVD-TiSiN thin film according to the present invention,
Sectional drawing which shows the example used for the capacitor structure, such as AM.

FIG. 5 shows a thermal CVD-TiSiN thin film according to the present invention,
Sectional drawing which shows the other example used for the capacitor structures, such as AM.

FIG. 6 shows a thermal CVD-TiSiN thin film according to the present invention,
Sectional drawing which shows the other example used for capacitor structures, such as AM.

FIG. 7 shows a thermal CVD-TiSiN thin film according to the present invention as a DR.
Sectional drawing which shows the further another example used for the capacitor structure of AM etc.

FIG. 8 shows the thermal CVD-TiSiN thin film according to the present invention being DR.
Sectional drawing which shows the further another example used for the capacitor structure of AM etc.

FIG. 9 is a sectional view showing an example in which a thermal CVD-TiSiN thin film according to the present invention is used for a contact portion of a metal wiring layer.

FIG. 10 is a sectional view showing an example in which a thermal CVD-TiSiN thin film according to the present invention is used for a gate electrode portion.

FIG. 11 is a sectional view showing another example in which the thermal CVD-TiSiN thin film according to the present invention is used for a gate electrode portion.

FIG. 12 is a sectional view showing still another example in which the thermal CVD-TiSiN thin film according to the present invention is used for a gate electrode portion.

[Explanation of symbols]

11; chamber 12; susceptor 15; heater 18; exhaust pipe 19; vacuum pump 20; shower head 33; TiCl ₄ source supply 34; SiH ₂ Cl ₂ supply 35; NH ₃ supply 51; lower electrode layer (poly Si) 52) barrier layer 53; insulating layer 54; upper electrode layer (thermal CVD-TiSiN thin film) 55; barrier layer (thermal CVD-TiSiN thin film) 61; poly Si plug 62; barrier layer (thermal CVD-TiSiN thin film) 63 Lower electrode layer 64; insulating layer 65; upper electrode layer 66; upper electrode layer (thermal CVD-TiSiN thin film) 67; lower electrode layer (thermal CVD-TiSiN thin film) 68; barrier layer (thermal CVD-TiSiN thin film) 63; Barrier layer (thermal CVD-TiSiN thin film) 72; contact hole 73; barrier layer (thermal CVD-TiSiN thin film) ) 74; the metal wiring layers 82; lower (thermal CVD-TiSiN film) 87,94; barrier layer (thermal CVD-TiSiN film) 84,89,96; gate electrode W; semiconductor wafer

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 21/822 H01L 27/10 621Z 5F083 27/108 621C 21/8242 651 29/78 29/78 301G F-term (Reference) 4K030 AA02 AA06 AA11 AA13 BA01 BA18 BA20 BA22 BA29 BA38 BA42 BB12 FA10 LA02 LA12 4M104 AA01 BB01 BB04 BB25 BB30 CC05 DD44 DD45 EE03 FF13 FF18 GG09 GG16 GG19 HH05 HH13 HH08HJ13HH13 GG19 GG19 GG19 GG13 MM13 QQ09 QQ37 XX02 XX03 XX10 XX20 XX28 5F038 AC05 AC09 AC15 DF05 EZ20 5F040 DA01 DB09 DC01 EA08 EC01 EC04 EC09 EC12 EC19 ED03 ED04 5F083 AD21 GA09 GA27 GA30 JA02 JA06 JA14 JA15 JA19 JA36 JA36 JA36 JA36 JA36

Claims (28)

[Claims] 1. A TiSiN thin film formed by thermal CVD. 2. A gas containing Ti, a gas containing Si, and N
TiS by thermal CVD using film forming gas containing gas
A method for forming a TiSiN thin film, comprising forming an iN thin film. 3. The method according to claim 1, wherein the Ti-containing gas is TiCl ₄ ,
3. The method according to claim 2, wherein at least one of tetraxydimethylaminotitanium and tetraxydiethylaminotitanium is used. 4. The method according to claim 1, wherein the Si-containing gas is SiH ₂ Cl.
₂ , SiHCl ₃ , SiCl ₄ , Si ₂ H ₄ , Si ₂ H
_6. The method according to claim 2, wherein at least one of the above ₆ is used.
Alternatively, the method for forming a TiSiN thin film according to claim 3. 5. The method for forming a TiSiN thin film according to claim 2, wherein at least one of NH ₃ and monomethylhydrazine is used as the N-containing gas. 6. An insulating layer made of a high dielectric constant material, a lower electrode layer provided thereunder, an upper electrode layer provided on the insulating layer, and a gap between the insulating layer and the lower electrode layer. A capacitor portion having a barrier layer provided on the substrate, wherein the upper electrode layer is formed of TiSiN formed by thermal CVD.
A semiconductor device characterized by being a thin film. 7. An insulating layer made of a high dielectric constant material, a lower electrode layer provided thereunder, an upper electrode layer provided on the insulating layer, and a portion between the insulating layer and the lower electrode layer. A capacitor portion having a barrier layer provided on the substrate, wherein the barrier layer is a TiSiN thin film formed by thermal CVD. 8. An insulating layer made of a high dielectric constant material, a lower electrode layer provided thereunder, an upper electrode layer provided on the insulating layer, the lower electrode layer and a wiring layer therebelow. And a barrier portion provided between the first and second semiconductor devices, wherein the barrier layer is a TiSiN thin film formed by thermal CVD. 9. The semiconductor device according to claim 8, wherein at least one of the upper electrode layer and the lower electrode layer is formed of Pt or Ru. 10. The method according to claim 8, wherein said upper electrode layer is a TiSiN thin film formed by thermal CVD.
Alternatively, the semiconductor device according to claim 9. 11. The semiconductor device according to claim 8, further comprising a barrier layer comprising a TiSiN thin film formed by thermal CVD on the upper electrode layer. 12. An insulating layer made of a high dielectric constant material, a lower electrode layer provided thereunder, an upper electrode layer provided on the insulating layer, the lower electrode layer and a wiring layer thereunder. A capacitor portion having a barrier layer provided between the upper electrode layer and the lower electrode layer, wherein the upper electrode layer and the lower electrode layer are TiSiN thin films formed by thermal CVD. 13. The high dielectric constant material is (Ba, Sr)
TiO ₃ , Pb (Zr, Ti) O ₃ , Ta ₂ O ₅ , Ru
7. The method according to claim 6, wherein the selected one is O.
The semiconductor device according to claim 1. 14. A wiring layer, a buried wiring portion for connecting the wiring layer to a semiconductor substrate or a conductive layer thereon, and a barrier provided between the buried wiring portion and the semiconductor substrate or a conductive layer thereon. A TiSiN layer formed by thermal CVD.
A semiconductor device characterized by being a thin film. 15. A semiconductor device comprising: a gate electrode formed on a main surface of a semiconductor substrate via an insulating layer; and a gate electrode connected to a wiring layer, wherein the gate electrode is formed of TiSi formed by thermal CVD.
A semiconductor device having an N thin film. 16. The semiconductor device according to claim 15, wherein said gate electrode has a lower layer made of a TiSiN thin film formed by thermal CVD and an upper layer made of W formed thereon. 17. The gate electrode is formed on a semiconductor substrate, and is composed of Ba, Sr) TiO ₃ , Pb (Zr, Ti) O.
₃ , an insulating layer made of a material selected from Ta ₂ O ₅ and RuO, a conductive layer thereon, and a barrier layer made of a TiSiN thin film formed between the insulating layer and the conductive layer by thermal CVD. 16. The semiconductor device according to claim 15, comprising: 18. The semiconductor device according to claim 17, further comprising an SiO _x N _y thin film between said semiconductor substrate and said insulating layer.
3. The semiconductor device according to claim 1. 19. A step of forming a lower electrode layer; a step of forming a barrier layer on the lower electrode layer; a step of forming an insulating layer made of a high dielectric constant material on the barrier layer; Forming a capacitor portion by forming an upper electrode layer thereon; and forming the barrier layer by thermal CVD using a deposition gas containing a Ti-containing gas, a Si-containing gas, and an N-containing gas.
A method for manufacturing a semiconductor device, which is obtained by forming a SiN thin film. 20. A step of forming a lower electrode layer; a step of forming a barrier layer on the lower electrode layer; a step of forming an insulating layer made of a high dielectric constant material on the barrier layer; Forming a capacitor portion by a step of forming an upper electrode layer thereon, and forming the upper electrode layer by thermal CVD using a deposition gas containing a Ti-containing gas, a Si-containing gas, and a N-containing gas.
A method for manufacturing a semiconductor device, which is obtained by forming an iSiN thin film. 21. A step of forming a barrier layer on a wiring layer formed on a semiconductor substrate, a step of forming a lower electrode layer on the barrier layer, and a step of forming a lower electrode layer on the lower electrode layer from a high dielectric constant material. Forming a capacitor portion by a process of forming an insulating layer and a process of forming an upper electrode layer on the insulating layer, wherein the barrier layer is a film forming gas containing a Ti-containing gas, a Si-containing gas, and an N-containing gas. By thermal CVD using Ti
A method for manufacturing a semiconductor device, which is obtained by forming a SiN thin film. 22. A step of forming a barrier layer on a wiring layer formed on a semiconductor substrate; a step of forming a lower electrode layer on the barrier layer; Forming a capacitor portion by a step of forming an insulating layer and a step of forming an upper electrode layer on the insulating layer, wherein the barrier layer and the upper electrode layer include a Ti-containing gas,
A method for manufacturing a semiconductor device, characterized by being obtained by forming a TiSiN thin film by thermal CVD using a film forming gas containing a Si-containing gas and a N-containing gas. 23. A step of forming a lower electrode layer on a wiring layer formed on a semiconductor substrate; a step of forming an insulating layer made of a high dielectric constant material on the lower electrode layer; Forming a capacitor portion by the step of forming an upper electrode layer, wherein the lower electrode layer and the upper electrode layer are made of TiSiN by thermal CVD using a deposition gas containing a Ti-containing gas, a Si-containing gas, and an N-containing gas. A method for manufacturing a semiconductor device, which is obtained by forming a thin film. 24. A step of forming an insulating layer on a semiconductor substrate or a conductive layer thereon, a step of forming a contact hole or a via hole in the insulating layer by etching, A step of forming a barrier layer in the via hole and a step of forming a wiring layer on the barrier layer to form a buried wiring portion, wherein the barrier layer contains a Ti-containing gas, a Si-containing gas, and an N-containing gas. Ti by thermal CVD using a deposition gas containing
A method for manufacturing a semiconductor device, which is obtained by forming a SiN thin film. 25. TiS on a semiconductor substrate via an insulating layer
A gate electrode is formed by a step of forming a lower layer made of an iN thin film, and a step of forming an upper layer made of W on the lower layer. The lower layer made of the TiSiN thin film contains a Ti-containing gas, S
A method for manufacturing a semiconductor device, characterized by being formed by thermal CVD using a film forming gas containing an i-containing gas and an N-containing gas. 26. A step of forming an insulating layer made of a high dielectric constant material on a semiconductor substrate; a step of forming a barrier layer on the insulating layer; and a step of forming a conductive layer on the barrier layer. A gate electrode is formed by using a deposition gas containing a Ti-containing gas, a Si-containing gas, and an N-containing gas.
A method for manufacturing a semiconductor device, which is obtained by forming a SiN thin film. 27. The method according to claim 26, further comprising forming a SiO _x N _y thin film between the semiconductor substrate and the insulating layer. 28. A chamber accommodating a substrate to be processed, a support member for supporting the substrate to be processed in the chamber, a film formation gas introduction mechanism for introducing a film formation gas into the chamber, and a support member supported by the support member. A heating mechanism for heating the substrate to be processed; wherein the film formation gas introducing mechanism has a supply source of a Ti-containing gas, a Si-containing gas, and a N-containing gas, and the substrate to be heated heated by the heating mechanism. Thermal CVD on
Forming a TiSiN thin film on a substrate by using the method.