JPH1088353A - Formation of zrn coating using cvd system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce coating thickness and to obtain stabler thin coating by simultaneously feeding a specified source converted into a gaseous state and reactive gases into a chamber and forming coating. SOLUTION: A wafer 32 is placed on a susceptor 31 at the lower part of a reaction chamber 30 in a CVD device. Next, a valve 37 is opened, and by using a carrier gas such as He, any one of source among three kinds of Zr [N (CH3 )2 ] or the like in an isothermal chamber 38 is fed to a shower head 33 in the reaction chamber. At this time, preferably, the source is heated at about 40 to 200 deg.C, is evaporated to form into a gaseous state and is flowed into the shower head 33 together with reactive gases such as N2 and H2 fed through a valve 35. In this way, the CVD process is performed, and ZrN coating is deposited on a semiconductor or the like. This ZrN coating is stabler than the conventional TiN coating, is furthermore small in resistance, reduces the coating thickness of diffused coating and reduces the parasitic resistance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a ZrN film using a CVD apparatus, and particularly to a method for forming a ZrN film using a CVD apparatus which is easy to apply to wiring and high dielectric film electrodes.
The present invention relates to a method for forming a film.

[0002]

2. Description of the Related Art In general, in a vapor phase growth method (CVD), one or two or more individual gases or compounds composed of elements constituting a thin film material to be formed are supplied onto a substrate.
It refers to a method for forming a desired thin film by a gas phase or a chemical reaction on the surface of a substrate. This CVD method originated from the development of the epitaxial growth technology and has evolved in response to the advancement of device technology, and has become one of the basic technologies in LSI as of today. The formation of a CVD film is, as is literally, an application of a chemical vapor reaction, and the temperature, pressure, gas mixture ratio, concentration and the like are very important factors as in the case of epitaxial growth. In accordance with the type and purpose of the film to be formed by the CVD method, the material to be selected, the reaction type, the structure of the reactor, and the like should be sufficiently checked in advance. Materials that can be formed by the CVD method include amorphous materials (insulating films), polycrystals (polysilicon), single crystals (silicon, germanium), and the like.
Alternatively, an insulating film, a metal film, a semiconductor film, or the like can be considered.

[0003] Referring to the accompanying drawings,
A method for forming a thin film using the method will be described. FIG. 1 is a configuration diagram of a CVD apparatus for explaining a thin film forming method using a thermal CVD method. Susceptor 1 in reaction chamber 10
1 is disposed horizontally, and a shower head 13 is disposed above the horizontal position. The wafer 12 is placed on the susceptor 11. Further, a first gas supply pipe 14 connected to the shower head 13 is provided at an upper portion of the reaction chamber 10 (in the drawing, when a direction is indicated below, unless otherwise specified, all are on the drawing). A first control valve 15 for controlling the amount of gas flowing through the first gas supply pipe 14 is provided. On the left side of the reaction chamber 10, there is disposed a constant temperature chamber 18 for accommodating a liquid source, evaporating the liquid source constantly to generate gas, and a second gas supply pipe 16 between the constant temperature chamber 18 and the shower head 13. And a second control valve 17 for controlling the amount of gas flowing through the second gas supply pipe 16.

In the above-described conventional thin film forming method, TiN
To form a film, Ti [N (C ₂ H ₅ ) ₂ ] ₄ and Ti [N
(CH ₃ ) ₂ ] ₄ and Ti [N (CH ₃ ) (C ₂ H ₅ )] ₄ as a source using any one of thermal CV
Deposit in the D method. Susceptor 1 on which wafer 12 is placed
1 has a heating function. The wafer 12 is placed on the susceptor 11 having the heating function, the second control valve 17 is opened, and a constant temperature chamber 18 is formed using a carrier gas such as He, Ar, H ₂ , N ₂ , and a mixed gas. Ti in
[N (C ₂ H ₅ ) ₂ ] ₄ , Ti [N (CH ₃ ) ₂ ] ₄ , Ti [N
(CH ₃ ) (C ₂ H ₅ )] ₄ is supplied to the shower head 13 inside the reaction chamber 10. Further, the first control valve is opened and N ₂ , H ₂ , NH ₃ , H
e, and a reaction gas such as a mixed gas is caused to flow into the shower head 13 inside the reaction chamber 10 to deposit a TiN film on the wafer 12.

FIG. 2 is a configuration diagram of a CVD apparatus for explaining a thin film forming method using a plasma CVD method. In this case, the susceptor 21 is horizontally disposed in the reaction chamber 20 and the shower head 23 is disposed above the susceptor 21 as described above. The wafer 22 is placed on the susceptor 21. Further, a first gas supply pipe 24 connected to the shower head 23 and a first gas supply pipe 24
A first control valve 25 that adjusts the amount of gas flowing through the hopper and an RF generator 29 that activates the flowing gas are disposed. On the left side of the reaction chamber 20, a liquid source, a constant temperature chamber 28 for generating a gas by evaporating the liquid source constantly, a second gas supply pipe 26 through which the gas flows, and a second gas supply pipe 26
And a second control valve 27 for controlling the amount of gas flowing through the second control valve 27.

The thin film forming method according to the prior art described above includes:
Ti [N (C ₂ H ₅ ) ₂ ] ₄ , Ti [N (CH ₃ ) ₂ ] ₄ ,
Any one of Ti [N (CH ₃ ) (C ₂ H ₅ )] ₄
Using one of them as a source, a TiN film is deposited by a plasma CVD method. The wafer 22 is placed on the susceptor 21 having a heating function below the reaction chamber 20 of the CVD apparatus, the second control valve 27 is opened, and He, Ar, H ₂ , N ₂ , and mixed gas Ti in the constant temperature chamber 28 using carrier gas
A source such as [N (C ₂ H ₅ ) ₂ ] ₄ or Ti [N (CH ₃ ) ₂ ] ₄ flows into the shower head 23 inside the reaction chamber 20. A reaction gas such as N ₂ , H ₂ , NH ₃ , He, and a mixed gas is activated by applying a power of 0.01 to 5 KW to the RF generator 29 and then flows into the shower head 23 inside the reaction chamber 20. Then, a TiN film is deposited on the wafer 22.

[0007]

SUMMARY OF THE INVENTION In the prior art described above, T
An iN film was formed by a CVD method and used as a diffusion prevention film, an adhesion layer, a Ta ₂ O ₅ or BST dielectric film, or the like. However, from the viewpoint of securing a good step coverage to compensate for the unevenness due to the decrease in the pattern size of the device, in the case of the CVD method using TiN, instability of the deposited film, that is, deterioration due to the aging effect, or high There are limits to the application due to the deposition temperature. The present invention has been proposed to solve the above-mentioned conventional problems, and provides a film forming method using a CVD apparatus so as to reduce the thickness of a thin film and obtain a more stable thin film. The purpose is to:

[0008]

In order to achieve the above object, a method of forming a ZrN film using a CVD apparatus according to the present invention is as follows. A substrate is placed in a chamber of a CVD apparatus, and Zr [N (CH ₃ ) is used as a source. ₂ ] ₄ , Zr [N (C
_{2 H 5) 2] 4,} Zr [N (CH 3) (C 2 H 5)] 4 was prepared, and the source gas state by supplying a vaporized gas to its source, supplying it to the chamber I do. At the same time C
A VD reaction gas is supplied into the chamber and Z is supplied to the substrate.
It is characterized in that an rN film is formed.

[0009]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 3 is a configuration diagram of a CVD apparatus for describing a method of forming a thin film by a thermal CVD method according to the first embodiment of the present invention. As in the conventional case, the susceptor 31 is kept substantially horizontal in the reaction chamber 30, and the shower head 33 is provided on the ceiling. Susceptor 31
A wafer 32 is placed on the wafer. In addition, a first gas supply pipe 34 connected to the shower head 33 and a first control valve 35 for adjusting an amount of gas flowing through the first gas supply pipe 34 are disposed above the reaction chamber 30. Also, the reaction chamber 30
A constant temperature chamber 38 for storing a liquid source, evaporating the liquid source at a constant rate, and generating gas is disposed on the left side of the liquid source, and the constant temperature chamber 38 and the shower head are connected by a second gas supply pipe 36. The second gas supply pipe 36 is provided with a second control valve 37 for controlling the amount of gas flowing therethrough.

In the method for forming a thin film according to the present embodiment, first, a wafer 32 is placed on a susceptor 31 having a heating function below a reaction chamber 30 of a CVD apparatus. Next, the second control valve 37 is opened, and He, Ar,
Using a carrier gas such as H ₂ , N ₂ and a mixed gas, Zr [N (CH ₃ ) ₂ ] ₄ and Zr [N (C
₂ H ₅ ) ₂ ] ₄ , Zr [N (CH ₃ ) (C ₂ H ₅ )] ₄ , and any one of the sources is used as a shower head 33 in the reaction chamber.
To supply. At this time, the source is heated at a temperature of about 40 to 200 ° C. to evaporate to a gaseous state, and then N ₂ , H ₂ , NH
₃ , it is preferable to flow into the shower head 33 inside the reaction chamber together with a reaction gas such as He and a mixed gas thereof. Further, the first control valve 35 is opened, and N ₂ , H ₂ , NH
_A CVD process is performed by flowing a reaction gas such as ₃ , He, and a mixed gas thereof into the shower head 33 inside the reaction chamber. At this time, the ZrN film is made of silicon (Si), a semiconductor such as a compound semiconductor such as GaAs, SiO ₂ , Si
N ₄ , a dielectric such as a polymer, Ti, Cu, Al, W,
It is deposited on a metal such as Mo, a high dielectric film such as Ta ₂ O ₅ , BST, PZT or the like. On the other hand, Ta ₂ O ₅ , BS
A dielectric such as T is deposited, and can be used again as a capacitor electrode formed of a ZrN film. During the formation of the ZrN film, the deposition temperature inside the reaction chamber is about 25 to 450 ° C., and the pressure is 10 ^{−3 to} 760 Torr. The temperature of the sauce is between 40 and 200C. After the formation of the ZrN film, N ₂ / H ₂ or NH ₃ or N ₂ / H ₂ / NH ₃ is used to reduce impurities such as carbon and increase the film density.
Annealing is preferably performed at 500 ° C. or more in the above atmosphere.

FIG. 4 is a configuration diagram of a CVD apparatus for explaining a method of forming a thin film by a plasma CVD (PECVD) method according to a second embodiment of the present invention. As described above, a susceptor 41 is disposed substantially horizontally in the reaction chamber 40, and a shower head 43 is attached to the ceiling. A wafer 42 is placed on the susceptor 41. Further, a first gas supply pipe 44 connected to the shower head 43, a first control valve 45 for controlling the amount of gas flowing through the first gas supply pipe 44, and a control valve 45 are provided above the reaction chamber 40. An RF generator 49 for activating the flowing gas is arranged. On the left side of the reaction chamber 40, a constant temperature chamber 48 for storing a liquid source, evaporating the liquid source constantly to generate gas, and a second gas supply between the constant temperature chamber 48 and the shower head 43 are provided. A pipe 46 is arranged, and a second gas supply pipe 46 is provided with a second gas supply pipe 46 for adjusting the amount of gas flowing therethrough.
A control valve 47 is attached.

In the above-described thin film forming method according to the present embodiment, the wafer 42 is placed on the susceptor 41, the second control valve 47 is opened, and carriers such as He, Ar, H ₂ , N ₂ , and a mixed gas are mixed. Using a gas, Zr [N (C
_{H 3) 2] 4, Zr} [N (C 2 H 5) 2] 4, and Zr [N (C
H ₃ ) (C ₂ H ₅ )] ₄ is supplied to the shower head 43 inside the reaction chamber 40. At this time, the source is heated at a temperature of about 40 to 200 ° C. to evaporate to a gaseous state, and then is showered inside the reaction chamber together with a reaction gas such as N ₂ , H ₂ , NH ₃ , He, and a mixed gas. It is preferable to flow into the head 43. At the same time, the first control valve 45 is opened, and the reaction gas is activated by applying a power of 10 to 500 KW to the RF generator 49, and then flows into the shower head 43 inside the reaction chamber 40, and Then, a ZrN film is deposited.

This ZrN film is made of silicon (Si) and Ga
Semiconductors such as compound semiconductors such as As, SiO ₂ , SiN ₄ ,
It is deposited on a dielectric such as a polymer, a metal such as Ti, Cu, Al, W, and Mo, or a high dielectric film such as Ta ₂ O ₅ , BST, or PZT. On the other hand, a dielectric such as Ta ₂ O ₅ or BST is deposited on the ZrN film, and can be used again as a capacitor electrode formed of the ZrN film. The deposition temperature inside the reaction chamber 40 during the formation of the ZrN film is about 25 to 450 ° C., and the pressure is 10 ^{−3 to} 760 Torr. After the formation of the ZrN film, N ₂ / H ₂ , NH ₃ , or N ₂ / H is used to reduce impurities such as carbon and increase the film density.
Annealing is preferably performed at 500 ° C. or higher in an atmosphere of ₂ / NH ₃ .

[0014]

According to the present invention described above,
The ZrN film is more stable than the TiN film, has lower resistivity, reduces the thickness of the diffusion film, and reduces the parasitic resistance. Also, R
This has the effect of increasing the operating speed of the device due to the decrease in the C time constant. The present invention is not limited to the above-described embodiments, and it is apparent that various modifications can be made by those having ordinary knowledge in the art within the technical spirit of the present invention.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a CVD apparatus for explaining a thin film forming method using thermal CVD according to a conventional technique.

FIG. 2 is a configuration diagram of a CVD apparatus for explaining a thin film forming method using plasma CVD according to a conventional technique.

FIG. 3 is a configuration diagram of a CVD apparatus for explaining a thin film forming method using thermal CVD according to an embodiment of the present invention.

FIG. 4 is a configuration diagram of a CVD apparatus for explaining a thin film forming method using a plasma enhanced chemical vapor deposition method according to an embodiment of the present invention.

[Explanation of symbols]

 30, 40 Reaction chamber 31, 41 Susceptor 32, 42 Wafer 33, 43 Shower head 34, 44 First gas supply pipe 35, 45 First control valve 36, 46 Second gas supply pipe 37, 47 Second control valve 38, 48 constant temperature room 49 RF generator

Claims (4)

[Claims] 1. A substrate is placed in a chamber of a CVD apparatus; Zr [N (CH ₃ ) ₂ ] ₄ and Zr [N
(C ₂ H ₅ ) ₂ ] ₄ and Zr [N (CH ₃ ) (C ₂ H ₅ )] ₄ are prepared; a gas for vaporization is supplied to the source to convert the source into a gaseous state; Into the chamber; CVD
Reaction gas is supplied into the chamber and ZrN
Forming a film; Z using a CVD apparatus
A method for forming an rN film. 2. The gas for vaporization is He, Ar,
_{2. The} Z using a CVD apparatus according to claim 1, wherein the Z is one of N ₂ , H ₂ , and a mixed gas.
A method for forming an rN film. 3. The CVD gas is N ₂ , He,
_{2. The} method for forming a ZrN film using a CVD apparatus according to claim 1, wherein the ZrN film is one of H ₂ , N ₂ H ₃ , and a mixed gas. 4. The ZrN film includes a semiconductor, a dielectric, a metal,
2. The ZrN using a CVD apparatus according to claim 1, wherein the ZrN is deposited on any one of the first dielectric film and the high dielectric film.
Method of forming a film.