KR100528446B1 - Fabricating method of bit line contact in semiconductor device - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a contact of a semiconductor memory device, and in particular, to form a multi-diffusion barrier film and a TiSi silicide at the same time, thereby simplifying the process and improving the electrical characteristics of the device. To this end, the present invention comprises the steps of forming a contact hole through the interlayer insulating film formed on the substrate to expose the region containing silicon; Forming a TiN film containing excess titanium along the step hole of the contact hole; Heat-treating in a silane gas plasma atmosphere to form Ti-Si bonds on the surface of the TiN film containing the excess titanium; Heat treating in a nitrogen atmosphere to form a TiSiN film on the surface of the TiN film containing excess titanium, and simultaneously reacting excess titanium of the TiN film containing excess titanium with silicon in the silicon-containing region to form titanium silicide; step; A surface treatment step of improving the film quality of the TiN film containing the excess titanium; And filling the contact hole with a plug.

Description

Method for forming contact of semiconductor device {FABRICATING METHOD OF BIT LINE CONTACT IN SEMICONDUCTOR DEVICE}

The present invention relates to a method for forming a bit line contact of a semiconductor memory device. In particular, the present invention simplifies and improves the process by simultaneously forming a plurality of diffusion barrier films and titanium silicide films by controlling the composition of the TiN film.

In manufacturing a semiconductor memory device, a bit line contact forming process is a process for electrical connection between a bit line and a semiconductor substrate or a bit line and a gate electrode. Referring to FIGS. 1A to 1C, a bit line contact forming process according to the prior art will be described. Is as follows.

First, FIG. 1A illustrates a gate stack formed on the semiconductor substrate 10 and a bit line contact hole A passing through the interlayer insulating layer 16.

Typically, the gate stack includes a gate insulating film 11, a gate polysilicon 12, a tungsten silicide 13, and a hard mask, but a hard mask is not shown in FIG. 1A.

After the gate stack is formed in this manner, the spacer 14 and the source / drain regions 15 doped with p-type or n-type are formed, and an interlayer insulating film 16 made of an oxide film or the like is deposited on the entire structure.

Thereafter, a predetermined portion of the interlayer insulating layer 16 is removed to form a bit line contact hole A exposing an upper portion of the semiconductor substrate or the gate stack.

Here, the bit line contact hole is formed in both the cell region and the peripheral circuit region. In particular, the bit line contact hole formed in the peripheral circuit region is formed in the upper portion of the gate stack in addition to the source / drain region.

After the bit line contact holes are formed in this manner, a state in which the Ti film 17 and the first TiN film 18 are stacked is shown in FIG. 1A.

Next, as shown in FIG. 1B, a high temperature thermal process of 800 ° C. or higher is performed for ohmic contact to react the titanium atom with silicon to form a silicide film TiSix 19. Next, the TiN film 20 is once again deposited.

The reason for depositing the TiN film 20 once again in the prior art is as follows. This is because the first TiN film 18 previously deposited through the preceding process is reduced in volume in a high temperature thermal process for forming silicide, thereby degrading its function as a diffusion barrier.

That is, after depositing the first TiN film 18, the bit line contact hole is filled with a plug material in a subsequent process. Tungsten or the like is used as the plug material, and the tungsten plug is formed using WF ₆ as a source.

At this time, the first TiN film 18 serves to block the diffusion of impurities (especially fluorine) that have an electrically bad effect, but since the volume is reduced, the first TiN film 18 does not perform such a role faithfully. In addition, the second TiN film 20 is deposited.

After forming the second TiN film in this manner, as shown in FIG. 1C, tungsten (W) is coated on the entire structure to fill the contact holes, and then the surface is flattened by chemical mechanical polishing or etchbeck process. In FIG. 1C, the portion denoted by 20 ′ is a combination of the first TiN film 18 and the second TiN film 20.

In the related art, the TiN film is deposited twice, thus adversely affecting the electrical characteristics and the process simplification of the transistor, and there is also a problem that the economic burden increases due to the introduction of excess process.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and by controlling the composition ratio of the TiN film, a plurality of diffusion barrier and silicide films are simultaneously formed to simplify the process and to provide a method for forming a bit line contact which improves the electrical characteristics of the device. It is done.

The present invention for achieving the above object comprises the steps of forming a contact hole through the interlayer insulating film formed on the substrate to expose the region containing silicon; Forming a TiN film containing excess titanium along the step hole of the contact hole; Heat treating in a nitrogen atmosphere to react the excess titanium of the excess titanium-containing TiN film with silicon in the silicon-containing region to form titanium silicide; A surface treatment step of improving the film quality of the TiN film containing the excess titanium; And filling the contact hole with a plug.

In addition, the present invention comprises the steps of forming a contact hole through the interlayer insulating film formed on the substrate to expose the region containing silicon; Forming a TiN film containing excess titanium along the step hole of the contact hole; Heat-treating in a silane gas plasma atmosphere to form Ti-Si bonds on the surface of the TiN film containing the excess titanium; Heat treating in a nitrogen atmosphere to form a TiSiN film on the surface of the TiN film containing excess titanium, and simultaneously reacting excess titanium of the TiN film containing excess titanium with silicon in the silicon-containing region to form titanium silicide; step; A surface treatment step of improving the film quality of the TiN film containing the excess titanium; And filling the contact hole with a plug.

In the present invention, a TiN film was deposited, but an excessive amount of titanium was contained in the TiN film in the composition of the TiN film. Subsequently, by applying a nitrogen atmosphere heat treatment or a silane gas heat treatment, multiple diffusion barrier films and silicide films were simultaneously formed to simplify the process and improve characteristics.

Hereinafter, the most preferred embodiments of the present invention will be described with reference to the accompanying drawings so that those skilled in the art can easily implement the technical idea of the present invention.

2A to 2C illustrate a method of forming a bit line contact according to a first embodiment of the present invention, with reference to the second embodiment of the present invention.

First, a gate stack made of a gate insulating film 21, a gate polysilicon 22, and tungsten silicide (WSix) 23 is formed on a semiconductor substrate 50. The gate stack typically includes a hard mask but is not shown in Figure 2A.

Next, spacers 24 are formed on sidewalls of the gate stack, and junction regions (source / drain) 25 doped with p-type or n-type on both sides of the gate stack are formed. Next, an interlayer insulating film 26 made of an oxide film or the like is formed on the semiconductor substrate including the gate stack.

Next, the interlayer insulating layer 26 is selectively removed to form a bit line contact hole B exposing the source / drain region 25 or the top of the gate stack.

Next, a Ti _x N _1-x film 27 is deposited along the steps between the interlayer insulating film and the bit line contact hole. The Ti _x N _1-x film 27 used in the embodiment of the present invention is a film in which the content ratio of titanium (Ti) is increased compared with the prior art, and specifically, x has a value of 50 to 90 at%.

The Ti _x N _1-x film 27 has a different microstructure from that of a pure Ti film. That is, the grain size will be considerably smaller compared to pure Ti film. This means that the energy of titanium is present in the TiN thin film in a high state, that is, the driving force for diffusion of titanium is high.

The Ti _x N _1-x film 27 according to the first embodiment of the present invention is deposited using physical vapor deposition, chemical vapor deposition, or monoatomic deposition, and has a deposition thickness of about 100 to 1000 Pa and a temperature of 25 to 700 ° C. Is deposited on.

When such a Ti _x N _1-x layer (27) to heat treatment in a nitrogen atmosphere, Ti _x N is formed in the film thin TiN surface of the _1-x film 27, and at the same time the silicon and Ti _x N _1-x layer (27 At the interface), TiSi ₂ phase is formed by interdiffusion and reaction of silicon and excess titanium.

The heat treatment process in the above-described nitrogen atmosphere will be described with reference to FIG. 2B. Referring to FIG. 2B, the Ti _x N _1-x film 27 is heat-treated in a nitrogen atmosphere to form TiSi 2 28 at the interface between the silicon and the Ti _x N _1-x film 27. _The thin TiN film is formed on the surface of the _x N _1-x film 27. In Fig. 2B, a thin TiN film formed on the surface of the Ti _x N _1-x film 27 is not shown separately.

The heat treatment of the nitrogen atmosphere shown in FIG. 2B will now be described. Heat treatment of the nitrogen atmosphere may be heat treatment in a furnace at a temperature of 500 to 800 ℃ in an atmosphere containing nitrogen and ammonia, or rapid heat treatment for 10 to 300 seconds at a temperature of 500 to 800 ℃ in an atmosphere containing nitrogen and ammonia. You may.

In the first embodiment of the present invention, there is an advantage in that a TiN film and a TiSi ₂ film having low electrical resistance can be simultaneously formed in one heat treatment process. In addition, in the first embodiment of the present invention, since the thickness of the silicide can be formed very thin, there is an advantage that the damage of the surface can be minimized by lowering the ion implantation energy during the ion implantation process.

As such, after forming a diffusion barrier film consisting of _two layers of TiN / TiSi ₂ at the interface with silicon through heat treatment in a nitrogen atmosphere, the surface treatment process is performed on the TiN film 27.

Through the surface treatment of the TiN film 27, the surface of the TiN film 27 is filled with oxygen to obtain a dense and uniform surface, thereby improving the characteristics of the diffusion barrier film.

The surface treatment of the TiN film 27 is performed by rapid heat treatment at a temperature of 100 to 650 ° C. for 1 to 5 minutes in an O ₂ , Ar, O ₂ + Ar or N ₂ + O ₂ atmosphere to provide a surface of the TiN film 27. Can be filled with oxygen.

Alternatively, after ionizing oxygen, the ionized oxygen may be accelerated to strike the TiN film 27 to make the film quality of the TiN film 27 dense. At this time, the process is performed for 1 to 5 minutes at a temperature of 100 to 650 ℃.

Alternatively, after ionizing nitrogen or argon, the surface of the TiN film 27 may be densified with ionized nitrogen or argon to densify the film, and then a uniform oxide layer may be formed of oxygen ions. At this time, the process is performed for 1 to 5 minutes at a temperature of 100 to 650 ℃.

Alternatively, oxygen and argon may be ionized simultaneously to strike the surface of the TiN film 27 to densify the film, and then form a uniform oxide layer with oxygen ions. At this time, the process is performed for 1 to 5 minutes at a temperature of 100 to 650 ℃.

Alternatively, oxygen and nitrogen may be ionized simultaneously to strike the surface of the TiN film 27 to densify the film, and then form a uniform oxide layer with oxygen ions. At this time, the process is performed for 1 to 5 minutes at a temperature of 100 to 650 ℃.

Alternatively, after the heat treatment with NH ₄ in the chamber, a uniform oxide layer may be formed with oxygen ions, or after heat treatment with NH ₄ plasma, a uniform oxide layer with oxygen ions may be formed. At this time, the process is performed for 1 to 5 minutes at a temperature of 100 to 650 ℃.

Alternatively, after the heat treatment using oxygen plasma and NH ₄ plasma in the chamber, a uniform oxide layer may be formed of oxygen ions, or the above-described process may be performed using UV ozone.

As described above, in the first embodiment of the present invention, the TiN / TiSi ₂ structure diffusion barrier layer may be simultaneously formed through the first TiN film deposition and the first nitriding treatment, thereby simplifying the process.

After such a surface treatment process, tungsten 29, which is used as a plug material, is applied to the entire structure including the contact hole as shown in FIG. 2C. After that, a chemical mechanical polishing process or an etchbeck process is applied to planarize the surface, and a series of conventional processes are performed to finish contact formation.

Hereinafter, a second embodiment of the present invention will be described with reference to FIGS. 3A to 3C. In the second embodiment of the present invention, after forming a TiN film containing excess Ti, the silane gas (SiH ₄ ) plasma heat treatment, and then heat treatment in a nitrogen atmosphere to simultaneously form a double diffusion barrier and a TiSi2 silicide film having a TiSiN / TiN structure. Formed.

First, as shown in FIG. 3A, a gate stack including a gate insulating layer 31, a gate polysilicon 32, and tungsten silicide (WSix) 33 is formed on a semiconductor substrate 30. The gate stack typically includes a hard mask but is not shown in FIG. 3A.

Next, spacers 34 are formed on sidewalls of the gate stack, and p-type or n-type doped junction regions (source / drain) 35 are formed on both sides of the gate stack. Subsequently, an interlayer insulating film 36 made of an oxide film or the like is formed on the semiconductor substrate including the gate stack.

Next, the interlayer insulating layer 36 is selectively removed to form a bit line contact hole C through which the source / drain region 35 or the top of the gate stack is exposed.

Next, a Ti _x N _1-x film 37 is deposited along the steps between the interlayer insulating film and the bit line contact hole. The Ti _x N _1-x film 37 used in the second embodiment of the present invention is a film in which the content ratio of titanium (Ti) is increased compared to the prior art. Specifically, x has a value of 50 to 90 at%.

The Ti _x N _1-x film 37 has a microstructure different from that of a pure Ti film. That is, the grain size will be considerably smaller compared to pure Ti film. This means that the energy of titanium is present in the TiN thin film in a high state, that is, the driving force for diffusion of titanium is high.

The Ti _x N _1-x film 37 according to the second embodiment of the present invention is deposited using physical vapor deposition, chemical vapor deposition, or monoatomic deposition, and the deposition thickness is about 100 to 1000 Pa and the temperature is 25 to 700 ° C. Is deposited on.

After depositing such a Ti _x N _1-x film 37, heat treatment as shown in Fig. 3B is performed.

First, the heat treatment is performed in a silylene (SiH ₄ ) plasma atmosphere.

Through the heat treatment in the above-mentioned xylene (SiH ₄ ) plasma atmosphere, Ti-Si bonds are formed on the surface of the Ti _x N _1-x film 37 by reaction between silicon and excess titanium atoms. As a result, the Ti _x N _1-x film 37 has a structure of a double layer of a Ti-Si film formed on the surface and a TiN film below it.

Next, when the heat treatment is performed at a high temperature of about 800 ℃ and nitrogen atmosphere, the Ti-Si layer formed on the surface of the Ti _x N _1-x film 37 reacts with nitrogen to form a TiSiN film 38, At the same time, in the source / drain region 35 or in the tungsten silicide region 33 above the gate stack, a reaction between silicon and excess titanium atoms occurs to form a TiSi ₂ film 39.

That is, in FIG. 3B, when the source / drain region 35 or the tungsten silicide region 33 on the gate stack is centered, a stack of TiSiN 38 / Ti _x N _1-x 37 / TiSi ₂ 39 is formed. The structure is formed.

The formation of such a layered structure of TiSiN (38) / Ti _x N _1-x (37) / TiSi ₂ (39) not only has to be simple, but also to reduce the influence on the electrical characteristics of the device. The interfaces are preferably clean. In the second embodiment of the present invention, a stacked structure of TiSiN (38) / Ti _x N _1-x (37) / TiSi ₂ (39) can be obtained through a simple process, thereby ensuring the simplicity and ease of the process.

In addition, TiSiN 38 obtained according to the second embodiment of the present invention is a ternary based film in which three elements are combined, and has an advantage of excellent characteristics as a diffusion barrier as compared to a TiN membrane conventionally used as a diffusion barrier.

Hereinafter, the SiH ₄ plasma heat treatment and the heat treatment in a nitrogen atmosphere applied in the second embodiment will be described. First, the SiH ₄ plasma heat treatment is performed at a temperature of 25 to 500 ° C.

Next, the heat treatment in a nitrogen atmosphere may be heat treated in a furnace at a temperature of 500 to 800 ° C. in an atmosphere containing nitrogen and ammonia, or 10 to 300 at a temperature of 500 to 800 ° C. in an atmosphere containing nitrogen and ammonia. Rapid heat treatment for seconds is also possible.

In the second embodiment of the present invention, a diffusion barrier layer having a structure of TiSiN / TiN / TiSi ₂ may be formed through a silane gas plasma heat treatment and a heat treatment process in a nitrogen atmosphere. In addition, in the second embodiment of the present invention, since the thickness of the silicide can be formed very thin, there is an advantage that the damage of the surface can be minimized by lowering the ion implantation energy during the ion implantation process.

After performing the silane gas plasma heat treatment and the heat treatment in a nitrogen atmosphere, the surface quality of the TiSiN film 38 is performed to improve the film quality.

Through the surface treatment of the TiSiN film 38, the surface of the TiSiN film 38 may be filled with oxygen to obtain a dense and uniform surface, thereby improving characteristics of the diffusion barrier film.

The surface treatment of the TiSiN film 38 is performed by rapid heat treatment at a temperature of 100 to 650 ° C. for 1 to 5 minutes in an O ₂ , Ar, O ₂ + Ar, or N ₂ + O ₂ atmosphere to provide a surface of the TiSiN film 38. Can be filled with oxygen.

Alternatively, after ionizing the oxygen, the ionized oxygen may be accelerated to strike the TiSiN film 38 to densify the film quality of the TiSiN film 38. At this time, the process is performed for 1 to 5 minutes at a temperature of 100 to 650 ℃.

Alternatively, after ionizing nitrogen or argon, the surface of the TiSiN film 38 may be densified with ionized nitrogen or argon to densify the film, and then a uniform oxide layer may be formed of oxygen ions. At this time, the process is performed for 1 to 5 minutes at a temperature of 100 to 650 ℃.

Alternatively, oxygen and argon may be ionized simultaneously to strike the surface of the TiSiN film 38 to densify the film, and then form a uniform oxide layer with oxygen ions. At this time, the process is performed for 1 to 5 minutes at a temperature of 100 to 650 ℃.

Alternatively, oxygen and nitrogen may be ionized simultaneously to strike the surface of the TiSiN film 38 to densify the film, and then form a uniform oxide layer with oxygen ions. At this time, the process is performed for 1 to 5 minutes at a temperature of 100 to 650 ℃.

Alternatively, after the heat treatment with NH ₄ in the chamber, a uniform oxide layer may be formed with oxygen ions, or after heat treatment with NH ₄ plasma, a uniform oxide layer with oxygen ions may be formed. At this time, the process is performed for 1 to 5 minutes at a temperature of 100 to 650 ℃.

Alternatively, after the heat treatment using oxygen plasma and NH ₄ plasma in the chamber, a uniform oxide layer may be formed of oxygen ions, or the above-described process may be performed using UV ozone.

After such a surface treatment process, tungsten 40 used as a plug material is coated on the entire structure including the contact hole as shown in FIG. 3C. After that, a chemical mechanical polishing process or an etchbeck process is applied to planarize the surface, and a series of conventional processes are performed to finish contact formation.

In the second embodiment of the present invention, the TiSiN / TiN / TiSi ₂ structure diffusion barrier film can be simultaneously formed by silane gas plasma heat treatment and heat treatment in a nitrogen atmosphere after the first TiN film deposition. Providing a prevention film has the advantage that it is possible to surely prevent the diffusion of impurities.

As described above, the present invention is not limited to the above-described embodiments and the accompanying drawings, and the present invention may be variously substituted, modified, and changed without departing from the spirit of the present invention. It will be apparent to those of ordinary skill in Esau.

Applying the present invention, not only the simplification of the process but also the ease of the process can be obtained, and since the clean interface can be maintained, it is possible to manufacture a semiconductor device having excellent characteristics.

1A to 1C are cross-sectional views illustrating a process for forming a bit line contact according to the prior art;

2A to 2C are cross-sectional views illustrating a bit line contact forming process according to a first embodiment of the present invention;

3A to 3C are cross-sectional views showing a bit line contact forming process according to a second embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

30: substrate

31: gate insulating film

32: gate polysilicon

33: Tungsten Silicide

34: spacer

35: source / drain area

36: interlayer insulating film

37: Ti _x N _1-x

38: TiSiN

39: TiSi ₂

40: tungsten

Claims (24)

Forming a contact hole through the interlayer insulating film formed on the substrate to expose a region containing silicon; Forming a TiN film containing excess titanium along the step hole of the contact hole; Heat treating in a nitrogen atmosphere to react the excess titanium of the excess titanium-containing TiN film with silicon in the silicon-containing region to form titanium silicide; A surface treatment step of improving the film quality of the TiN film containing the excess titanium; And Filling the contact hole with a plug; Contact forming method of a semiconductor device comprising a. The method of claim 1, The excess titanium containing TiN film, A method of forming a contact for a semiconductor device, comprising a composition of Ti _x N _1-x (x = 50 to 90 at%). The method of claim 1, The heat treatment in the nitrogen atmosphere, A method for forming a contact in a semiconductor device, characterized in that the heat treatment in a furnace at a temperature of 500 ~ 800 ℃ in an atmosphere containing nitrogen and ammonia. The method of claim 1, The heat treatment in the nitrogen atmosphere, A rapid thermal treatment for 10 to 300 seconds at a temperature of 500 to 800 ℃ in an atmosphere containing nitrogen and ammonia. The method of claim 1, The surface treatment step, A method of forming a contact in a semiconductor device, characterized by rapid thermal treatment in an atmosphere of O ₂ , Ar, O ₂ + Ar or N ₂ + O ₂ . The method of claim 1, The surface treatment step, A method for forming a contact in a semiconductor device, wherein the ionized oxygen is accelerated by an electric field to improve the film quality of the TiN film. The method of claim 1, The surface treatment step, The ionized nitrogen or argon is accelerated by an electric field to hit the surface of the TiN film to make the film densely formed, and then forming a uniform oxide layer with oxygen ions. The method of claim 1, The surface treatment step, And ionizing oxygen and argon simultaneously to strike the surface of the TiN film to densify the film, and then form a uniform oxide layer with oxygen ions. The method of claim 1, The surface treatment step, And ionizing oxygen and nitrogen at the same time to strike the surface of the TiN film to densify the film, and then form a uniform oxide layer with oxygen ions. The method of claim 1, The surface treatment step, A method of forming a contact in a semiconductor device, characterized by forming a uniform oxide layer with oxygen ions after heat treatment with NH ₄ or NH ₄ plasma in the chamber. The method of claim 1, The surface treatment step, And heat-treating the chamber using oxygen plasma and NH ₄ plasma to form a uniform oxide layer with oxygen ions. The method according to any one of claims 5 to 11, The surface treatment step is a contact forming method of a semiconductor device, characterized in that performed for 1 to 5 minutes at a temperature of 100 ~ 650 ℃. Forming a contact hole through the interlayer insulating film formed on the substrate to expose a region containing silicon; Forming a TiN film containing excess titanium along the step hole of the contact hole; Heat-treating in a silane gas plasma atmosphere to form Ti-Si bonds on the surface of the TiN film containing the excess titanium; Heat treating in a nitrogen atmosphere to form a TiSiN film on the surface of the TiN film containing excess titanium, and simultaneously reacting excess titanium of the TiN film containing excess titanium with silicon in the silicon-containing region to form titanium silicide; step; A surface treatment step of improving the film quality of the TiN film containing the excess titanium; And Filling the contact hole with a plug; Contact forming method of a semiconductor device comprising a. The method of claim 13, The excess titanium containing TiN film, A method of forming a contact for a semiconductor device, comprising a composition of Ti _x N _1-x (x = 50 to 90 at%). The method of claim 13, The heat treatment in the nitrogen atmosphere, A method for forming a contact in a semiconductor device, characterized in that the heat treatment in a furnace at a temperature of 500 ~ 800 ℃ in an atmosphere containing nitrogen and ammonia. The method of claim 13, The heat treatment in the nitrogen atmosphere, A rapid thermal treatment for 10 to 300 seconds at a temperature of 500 to 800 ℃ in an atmosphere containing nitrogen and ammonia. The method of claim 13, The surface treatment step, A method of forming a contact in a semiconductor device, characterized by rapid thermal treatment in an atmosphere of O ₂ , Ar, O ₂ + Ar or N ₂ + O ₂ . The method of claim 13, The surface treatment step, And ionizing oxygen by an electric field to improve the film quality of the TiN film. The method of claim 13, The surface treatment step, The ionized nitrogen or argon is accelerated by an electric field to hit the surface of the TiN film to make the film densely formed, and then forming a uniform oxide layer with oxygen ions. The method of claim 13, The surface treatment step, And ionizing oxygen and argon simultaneously to strike the surface of the TiN film to densify the film, and then form a uniform oxide layer with oxygen ions. The method of claim 13, The surface treatment step, And ionizing oxygen and nitrogen at the same time to strike the surface of the TiN film to densify the film, and then form a uniform oxide layer with oxygen ions. The method of claim 13, The surface treatment step, A method of forming a contact in a semiconductor device, characterized by forming a uniform oxide layer with oxygen ions after heat treatment with NH ₄ or NH ₄ plasma in the chamber. The method of claim 13, The surface treatment step, And heat-treating the chamber using oxygen plasma and NH ₄ plasma to form a uniform oxide layer with oxygen ions. The method according to any one of claims 17 to 23, The surface treatment step is a contact forming method of a semiconductor device, characterized in that performed for 1 to 5 minutes at a temperature of 100 ~ 650 ℃.