JPS6326367A - Cvd method - Google Patents

Abstract

PURPOSE:To form an excellent metal thin film on a part of a substrate on which an insulating film is not formed by keeping the flows of a gas contg. a metal element and a reducing gas laminar, and allowing the materials to react discriminatingly by utilizing a difference in the radiant heat absorption. CONSTITUTION:The gas contg. a metal element is introduced into a reaction vessel 1 under reduced pressure in parallel with the surface of the substrate 3, and the gas Q consisting essentially of an inert gas id introduced in opposition to the surface of the substrate 3. A first metal thin film 10 is formed on the part of the substrate 3 on which the insulating thin film 9 is not formed. The gas R' contg. a second metal element and the reducing gas R are then intro duced from gas inlets 4a and 4b in parallel with the substrate 3 in the same way as before. The light of a heating lamp 8 is projected on the substrate 3, and a chemical reaction is caused only on the surface of the metal thin film 10 by utilizing a difference in the light absorptivity between the thin films 9 and 10. The second metal thin film 11 is then formed on the surface of the thin film 10.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention provides a method for removing the insulating thin film on the surface when the insulating thin film is formed on a part of the surface of the substrate and no insulating thin film is formed on the other part of the surface. The present invention relates to a CVD method for forming a metal thin film on an unformed portion.

[Conventional technology]

The apparatus used in the conventional CVD method is shown in FIG. In the same figure, (21) is a horizontal vacuum reactor. One side of the horizontal vacuum reactor (211) is provided with a reaction gas inlet, and WF, which is a gas containing metal elements, and a reducing gas are A mixture of gas with H8 is produced in a horizontal vacuum reactor +
It has been introduced in 211. A reaction gas exhaust port f231 is provided on the other side of the horizontal vacuum reactor I211.

A mixed gas of H7 and H7 is exhausted. Inside the horizontal vacuum reactor Qυ, a substrate support plate (24+) is arranged horizontally,
A plurality of substrates (251) are vertically held on the substrate support plate (2) at regular intervals.A heating electric furnace is provided on the outer periphery of the horizontal vacuum reactor ρD.

Therefore, in the conventional CVD method, when the horizontal vacuum reactor ■ is heated with the heating electric furnace ■, the temperature of the furnace wall of the horizontal vacuum reactor (2υ) is raised, and the heat of the furnace wall of the horizontal vacuum reactor C? , and then to the substrate (251). Through such heat transfer, the heat is transferred to the substrate (251).
When 51 is heated, w
A chemical reaction occurs due to the mixed gas of F'6 and H2, and a thin film is formed on the substrate (g).

As shown in Fig. 16, an insulating thin film of SiO is formed on a part of the surface by the CVD method as described above.
1 substrate (the part where the insulating thin film τ of 251 is not formed)
When a metal thin film is formed on the substrate 25a), the portion (25a) on the surface of the substrate where the insulating thin film is not formed is initially expressed by the following equation (1).

wF11+3/2Si→3/2SiF, +w...song (1
) is thought to occur, and a W metal thin film 281 as shown in FIG. However, after that, the following (2) and (3)
) 3H, 6H・River・・・・・・・・・・・・・・・River・
(2) Back, +6H → 6I-IP + W song (
3) is thought to occur, and W grows over time, forming an initially formed W metal thin film (28
The next metal thin film (29) of W is formed on one surface as shown in FIG.

G= A [HLl v'2e x p (-Ea/k
Tm) --(4) where A is a positive constant, [general] is hydrogen concentration, Ea is activation energy, k is Boltzmann's constant, Tm
is the surface temperature of the part where the metal film grows.

[Problem that the invention seeks to solve]

In the conventional CVD method, as mentioned above, the temperature of the furnace wall of the horizontal vacuum reactor ρD is increased by heating the horizontal vacuum reactor ρD with the heating electric furnace (2). After the heat is transferred to the mixed gas of H2 and H2, it is transferred to the substrate (2) and the insulating thin film (5), heating them,
The part on the surface of 251 where no insulating thin film is formed (25
In a), a W metal thin film is formed.

However, since the surface temperature Tm of the portion (25a) on the surface of the substrate G where no insulating thin film is formed is equal to the surface temperature Ti of the insulating thin film, the insulating thin film (8) on the surface of the substrate is If the surface temperature - of the unformed portion (25a) is increased, the growth rate G of W increases, as can be seen from equation (4), but at the same time, the surface temperature Ti of the insulating thin film □□□ also increases. The W metal thin films (2) and (291) are not formed only on the part (25a) where the insulating thin film is not formed on the surface of the substrate, and the above (2) and (3) are not formed on the surface of the insulating thin film (27). ) chemical reaction occurs, and the first
There was a problem in that a metal thin film device of W greater than that shown in FIG. 8 was formed.

In addition, FIG. 19 shows an enlargement of a part of the substrate (251) shown in FIG. The encroachment that grows
ment) phenomenon was inevitable. In FIG. 19, t4G represents a metal element penetration site (encroachment).

Furthermore, a cavity (41) may be formed in the Si substrate (251).

In the conventional method, turbulent flow or natural convection occurs near the substrate ω, and the inventors of the present invention speculated that this may promote the growth of the encroachments (40) and cavities (411) described above.

-However, the only control parameters are the two internal parameters of pressure and reaction gas flow rate, and it is impossible to control them externally to suppress turbulence generation, natural convection, etc. Therefore, there is a problem in that it is not possible to form a metal film with excellent reproducibility, controllability, and uniformity over a wide pressure and flow rate range while suppressing the growth of encroachments and cavities. In addition, in any of the conventional methods, since the reaction components diffuse throughout the interior of the furnace, adhesion of the reaction components to the furnace walls, observation windows, etc. is unavoidable. This causes problems such as the generation of dust and the introduction of impurities into the thin film.

Low-temperature, low-concentration growth is considered as a means of suppressing encroachment phenomena and cavity formation, but the growth rate is only a few tens of A/min (Broadken et al.
l.

+T, El ect rochem, Soc,
131, iQ (1984); Bluewer,
VMIC (1985)), for example, had a problem in that it took nearly two hours to fill a contact hole with a depth of 1 μm.

This invention solves the problems of the conventional methods as described above, and forms a metal thin film only on the part of the substrate where the insulating thin film is not formed, as described above. It is an object of the present invention to provide a CVD method that can form a film at high speed while suppressing the growth of encroachments and cavities.

[Means for solving problems]

The above purpose is to introduce a gas containing at least a metal element in a sheet-like flow approximately parallel to the surface of the substrate in a reaction tank under reduced pressure, and to introduce an inert gas so as to face the surface of the substrate. While introducing a gas flow or a gas flow mainly consisting of an inert gas, an insulating thin film is formed on a part of the surface of the substrate. After forming the metal thin film, a gas containing the metal element and a reducing gas are introduced into the reaction tank in a sheet-like flow approximately parallel to the surface of the substrate and facing the surface of the substrate. While introducing a gas flow of an inert gas or a gas flow mainly composed of an inert gas, the substrate is irradiated with light from a heating lamp, and the light is absorbed by each of the insulating thin film, the substrate, and the first metal thin film. Applying a temperature difference between the insulating thin film and the first metal thin film using the difference in rate, causing a chemical reaction only on the surface of the first metal thin film,
a second film having the metal element on the surface of the first metal thin film;
This is achieved by the CVD method, which is characterized by forming a thin metal film.

[For production]

The gas flow of the gas containing the metal element and the reducing gas can be maintained in a laminar flow state with good controllability throughout the vicinity of the substrate. In other words, a gas flow of an inert gas or a gas flow mainly composed of an inert gas dynamically suppresses the rise of the gas flow of the above-mentioned metal element-containing gas and reducing gas near the substrate, and also suppresses the components of these gases. Prevent turbulent diffusion.

Further, since there is a temperature difference between the insulating thin film and the first metal thin film, a chemical reaction occurs only on the surface of the first metal thin film. As a result, (1) the flow of the metal-containing gas and the reducing gas is laminar, which suppresses the growth of encroachments and cavities and improves the controllability and reproduction of the metal thin film on other parts of the substrate surface. Excellent in sex.

(2) The second metal thin film can be formed only on the first metal thin film at high speed.

(3) Since the components of the gas mentioned above are suppressed only near the substrate, contamination of the furnace wall and viewing window can be prevented.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram of an apparatus used in an embodiment of the present invention. In the figure, (1) is a reaction tank that is depressurized. A substrate (3) placed on a rotatable substrate holder (2) is disposed within the reaction tank (1).

The lj1 part (Ia) of the reaction tank (1) is provided with two gas introduction parts (4a) and (4b) having slit-like openings, and reducing gas is introduced from one gas introduction part (4a). ,
is introduced into the reaction tank (]) in a sheet form, and from the other gas introduction part (4b), wp, which is a gas containing metal elements, is introduced into the reaction tank (]).
is introduced into the reaction tank (1) in the form of a sheet. H! introduced into the reaction tank (1)! and W are flowing along the surface of the substrate (3) in the reaction tank (1). The top (1)) of the reaction tank (1) is provided with a transparent quartz glass transmission window (5) and an inert gas introduction part (6). Gas ejection part of inert gas introduction part (6) (
6a) is made of transparent quartz glass in the form of a perforated plate, and is located below the quartz glass transmission window (5) to blow out M gas, which is an inert gas, downward into the reaction tank (1). It is supposed to be done. The M gas ejected downward into the reaction tank (1) flows along the surface of the substrate (3). In order to prevent the flow of H and WF from spreading upward during the flow, the flow is arranged so that it intersects the flow of H and WF almost perpendicularly upward. An exhaust part (7) is provided at the bottom (lc) of the reaction tank (1), and the ratio, WF, and M gas are pumped into the reaction tank (1).
The inside is being exhausted. An infrared lamp (8) is disposed outside the reaction tank (1) located above the main part (4b) of the reaction tank (1). The infrared rays from the infrared lamp (8) are transmitted through the quartz glass transmission window (5) and the gas ejection part (6a) of the inert gas introduction part (6) made of transparent quartz glass, and then are transmitted to the substrate ( 3) is designed to irradiate the surface.

Therefore, using the apparatus shown in FIG. 1, a part of the surface as shown in FIG. CVD when forming a W metal thin film on the portion (3a) where the insulating thin film (9) is not formed of the Si substrate (3) on which the insulating thin film (9) is formed.
The method involves introducing reducing gas H2 and gas containing metal elements into a reaction tank (1) under reduced pressure, and rotating the substrate holder (2) to maximize the strength. Infrared rays from an infrared lamp (8) with a wavelength of 1.1 to 3 μm are transmitted through a transmission window (5) made of quartz glass and a gas ejection part (6) of an inert gas introduction part (6) made of transparent quartz glass. 6a) is transmitted and irradiated onto the surface of the substrate (3), in the portion (3a) on the surface of the substrate (3) where the insulating thin film (9) is not formed, as in the conventional CVD method, At the initial stage, wF6+3 is expressed by the following equation (5).
/2Si→3/2SiF, +W curve (5) is thought to occur, and W corresponding to the first metal thin film
A metal thin film α0 is formed as shown in FIG. However, the chemical reaction shown by the above formula (1) stops automatically when the W metal thin film Q0 is formed on the part (3a) where the insulating thin film (9) is not formed on the surface of the substrate (3). S, W
It is known that the thickness of the metal thin film remains at less than 100 Å.

The substrate (3) of No. 31 has a very small absorption rate for infrared rays having a wavelength of 1.1 μm or more, and the insulating thin film (9) of Sin has a very small absorption rate for infrared rays of a wavelength of 31 tm or less.
It is known that the W metal thin film aQ has a large absorption rate in the entire wavelength range of 1.1 to 3 μm, as do the 8i substrate (3) and the 8102 insulating thin film (9). αQ is heated by the 8i0 insulating thin film @(9), and a pressure temperature difference is created between the W metal thin film and the Sin insulating thin film (9).

Therefore, only on the surface of the W metal thin film α0, 3H → 6H (6) shown by the following equations (6) and (7).
) WF + 6H→ 6HF + W... Mountain song (7
), W grows over time, and the W metal thin film corresponding to the second metal thin film becomes the W metal thin film α corresponding to the first metal thin film.
It is formed on the surface of Q as shown in FIG.

According to the above embodiment, initially, the portion (3a) on the surface of the substrate (3) where the insulating thin film (9) is not formed
After the W metal thin film Q0 is formed on and, the W metal thin film QQ and 8i0. The insulating thin film (9) and the infrared lamp (
The infrared rays from 8) create a temperature difference and a chemical reaction occurs only on the surface of the metal thin film part of W! As shown in FIG. In addition, the growth rate (symbol A) of the formation is higher than the growth speed (symbol B) obtained by the conventional method.

Furthermore, from the nozzle (4a), H8, which is a reducing gas, is ejected into the space A in the reaction tank (1) in the form of a two-dimensional jet as a reaction gas tank. Further, from the nozzle (4b), W, which is a gas containing a metal element, is supplied as a reaction gas R'.

is also ejected in the form of a two-dimensional jet. On the other hand, from the upper inert gas spouting part (6a), M
Gas is ejected downward. The ejection flow rates of the reaction gas R' and the inert gas Q can be controlled from the outside, but the flow rate of the latter is, for example, three times that of the former.

As shown in FIG. 6A, the flow of the reaction gas R1R' is limited to the vicinity of the substrate (3) and is in a laminar flow state. This seems to be because the flow of the inert gas Q suppresses the flow of the reactant gases R and R' from above, but this stabilizing effect is due to the combination of numerical values, millage, and tetrachloride. Confirmed by titanium method visualization experiment. Furthermore, when looking at the flow as a whole, as shown in Figure 3C, the flow of the reactant gases R and R' (hatched) is a localized laminar flow, and the flow of the inert gas Q is a localized laminar flow. The scope is defined. In other words, by controlling the flow rate of the inert gas Q, the shape, size, or area of the hatched portion can be controlled.

FIG. 6B shows a case where there is no flow of inert gas Q from above, but in this case, the flow of reactant gas R/ is diffused as shown, and becomes turbulent in the region of space r. This flow causes contamination of the furnace walls, viewing windows, etc., as in the conventional system.

However, according to this embodiment, the flow of the reactant gas R1' is stabilized as shown in FIG. 6A or FIG. 6C, so that the reactant components are limited only to the vicinity of the substrate (3) and are not exposed to the reactor wall. , contamination of viewing windows etc. is prevented. Therefore, the substrate (3
), it is possible to improve the film quality of the metal thin film W and reduce dust particles. That is,
As shown in FIG. 4, the next W metal thin film CIη corresponding to the second metal thin film is formed on the W metal thin film αQ.
The growth of 4α and cavities (4υ) can be suppressed, and the yield of device manufacturing can be improved.

In addition, since the flow of the reaction gas R5 is laminar, controllability is improved.
The substrate (3
) It becomes possible to control the thickness distribution of the metal film formed on the metal thin film (10) and the depth of encroachment.

Here, the theoretical basis of the effect of one type of gas 70 in this embodiment will be briefly described.

Although there are still some unknown points regarding the mechanism by which the flow conditions of the reactant gases 几 and 几′ affect the encroachment phenomenon,
It may be possible to formulate the following working hypothesis. Significant encroachment is caused by a silicon reduction reaction that should originally stop spontaneously when the silicon (Si) surface is covered with a thin metal film, i.e., +-8i→W + -Si F
4↑ This is a phenomenon in which the reaction continues even after the initial stage of the reaction.

At this time, the reaction gas is thought to be supplied through the gap between the metal thin film @α0qη and the side wall of the insulating film (9) and the fine gap between the metal thin film C*cIη crystal grain boundaries. In order for silicon reduction to continue to proceed at the metal thin film-silicon interface, the reaction product (Sin in the above reaction equation) must be effectively discharged into space. When a turbulent region exists near the surface of the substrate, the reaction products are rapidly diffused and discharged through the gap due to the pumping action caused by turbulent diffusion.

However, when the entire surface is covered with laminar flow, the discharge of reaction products is only due to molecular diffusion, and if the gap is sufficiently narrow, this is a slow process that can be ignored compared to turbulent diffusion. be. Based on the above hypothesis, it can be understood that gas flow control near the substrate surface is greatly involved in the encroachment phenomenon.

In this example, a comparative experiment was conducted under the same conditions of growth temperature, total pressure, and partial pressure of the reaction gas, with and without rectification of the gas flow R by the inert gas flow Q. At this time, the reactive gases used were tungsten hexafluoride () and hydrogen Ht as described above, and the inert gas used was argon M, the growth temperature was 400°C, and the total pressure was about 0.7To.
According to cross-sectional observation using an electron microscope when a tungsten (III) film was deposited in the contact hole by approximately 7000 mm, the horizontal and vertical erosion lengths were each 3200.8000 A or more when no inert gas flow Q was used. When using the inert gas flow Q, it was confirmed that the values were 400.8000λ or less.

Furthermore, through film formation experiments under a wide variety of conditions, it was confirmed that the encroachment suppression effect due to the rectification effect acts as a parameter independent of the growth temperature and pressure.

In the above embodiments, the reducing gas KH and the gas containing a metal element are used, but the reducing gas and the gas containing a metal element are not limited to these. For example, gases containing metal elements are MoF, , TaF, , CrF, , TiF, , Ti
CL, , MoCL, , S■L, , ALCL, etc. are also good. Also, although SiO is used for the insulating thin film (9), it is not limited to this, and for example, AI, o
l ,BSG(Borosil icateglass
) P2O (Phosphosilicate gl
ass), BPSG (Borophosphosil
oxide glass), or BN
, a nitride such as SiNx, or a compound such as 5iNxOy (where x and y are numerical values). Further, although a W metal thin film is used as the first metal thin film and the second metal thin film, the first metal thin film is not limited to this.
The metal thin film and the second metal thin film are, for example, Mo,
It may be a metal such as Ta, Cr, Ti, AI, or an alloy of these or an alloy of W.
Four elements (6) belonging to the genus are implanted by ion implantation to create a substrate in which at least the Si element is exposed in the portion (3a) on the surface of the Si substrate (3) where the insulating thin film (9) is not formed. But that's fine. Further, the substrate (3) may have any structure as long as a thin Si film is formed on the top layer.

For example, as shown in FIG. 8, a thin film α of Si may be formed on the surface of sapphire. Furthermore, when a W metal thin film corresponding to the first metal thin film is grown, the Si element previously exposed on the surface of the substrate (3) may be diffused into the W metal thin film. Mo corresponding to the metal thin film of No. 1,
When a metal thin film of metal such as Ta, Cr, Ti, AI, or an alloy of these or an alloy of W is grown, the Si previously exposed on the surface of the substrate (3) is grown.
The element may be diffused into a W metal thin film.

The wavelength that gives the maximum intensity of the infrared lamp (8) is 1.1~
Although the wavelength is set at 3 μm, the wavelength is not limited thereto, and may be any wavelength, for example, from 0.75 to 5 μm.

As shown in Fig. 9, a heating lamp is used, an optical filter is placed between the heating lamp α and a transparent quartz glass transmission window (5), and the light passes through the optical filter αO. For example, the wavelength that gives the maximum intensity of the light is 077i5~5.
It may be expressed in μm or the like. The infrared radiation from the infrared lamp (8) may be from the back side of the substrate (3), as shown in FIGS. i0 and 11. In FIGS. 10 and 11, the substrate holder (2) is made of a transparent material such as quartz, and α is an inert gas inlet. This inert gas prevents reactants from adhering to the infrared lamp (8) and the substrate holder (2). As shown in FIG. 12, the substrate holder (2) may be equipped with a heating means (g). Alternatively, an infrared lamp (8) may be provided within the transparent substrate holder (2). In this case, the upper infrared lamp (8) can be omitted. Further, although the substrate holder (2) is shown to be rotated in FIG. 1, it may not be rotated.

Furthermore, in the above embodiments, the nozzles (4a) and (4b) for ejecting the reaction gas tank R' had slit-like openings, but as shown in FIG. A large number of small holes f51) may be formed in the end wall of the hollow tube (50). In this case, a mixed gas of a gas containing a metal element and a reducing gas is ejected from the small hole 6D. Alternatively, as shown in FIG. 14, slits [11t6
3 may be formed.

Furthermore, in the above embodiments, a so-called perforated plate was used for the inert gas ejection part (6a), but instead of this, a transparent strainer or honeycomb (hon) having an appropriate aspect ratio may be used.
eycom) may also be used. Alternatively, this and a perforated plate may be used together.

Further, in the above embodiments, an inert gas was used as the gas facing the substrate, but instead of this, a gas partially containing a reactive gas may be used. In that case, this reactive gas needs to be a gas species that does not generate dust particles. For example, H!・N...0! etc. may be included.

In addition, in the above embodiment, the rice inlet (4a) and the toro (4b) were provided separately, but it is possible to integrate these into one and introduce the mixed gas into the tank (1). You may also do so.

〔Effect of the invention〕

Since the present invention has the above-described structure, it is possible to form a metal thin film at a high speed only on the part of the substrate where the insulating thin film is not formed on a part of the surface of the substrate. become. Moreover, a high-quality metal thin film can be formed by suppressing the growth of encavities and cavities.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view of a device used in an embodiment of the present invention, and FIG. 2 shows a portion of the surface of a substrate (3) having a sintered surface. An insulating thin film (9) is formed on the other parts of the surface (3a
3 is a cross-sectional view showing a state where the insulating thin film (9) is not formed on the substrate (3), and FIG. FIG. 4 is a cross-sectional view showing a state in which a W metal thin film αQ corresponding to the first metal thin film αQ is formed, and FIG.
A metal thin film aυ of W corresponding to the second metal thin film is placed on the surface of 0.
5 is a cross-sectional view showing the state in which the horizontal axis is 1000
7. The temperature of the substrate (K), the growth rate of the W metal thin film (
X/m1n) and W by the method of the embodiment of this invention
Growth rate of metal thin film (symbol A) and W by conventional method
Figures 6A to 6C are graphs showing the growth rate of a metal thin film (symbol B) and experimental data, respectively; Figures 6A to 6C are graphs showing the effect of gas flow; (3) is a cross-sectional view showing a state in which at least Si element is exposed in the part (3a) where the insulating thin film (9) is not formed, and FIG. FIG. 9 is a cross-sectional view showing the substrate (3) on which the grooves are formed. 10 and 11 are schematic configuration diagrams of a device that adjusts the wavelength that gives the maximum intensity of the light that has passed through the substrate (3) to, for example, 0.75 to 5 μm. ), and FIG. 12 is a cross-sectional view showing the substrate holder (2) equipped with heating means (to). FIGS. 13 and 14 are front views of main parts showing fifth and sixth modifications. FIG. 15 is a schematic cross-sectional view of an apparatus used in the conventional method, and FIG. 16 is a schematic sectional view of a device used in the conventional method.
, an insulating thin film (271) is formed, and other parts of the surface (
2Sa) is a cross-sectional view showing a state in which no insulating thin film □□□ is formed, and FIG. 17 is a state in which W metal thin film beads are formed on the portion (25a) on which the insulating thin film is not formed on the surface of the substrate. Figure 18 is a cross-sectional view showing the next W metal thin film formed on the surface of the initially formed W metal thin film, and Figure 19 is a partially enlarged cross-section of the substrate in Figure 18. It is a diagram. In the figure, (1)・・・・・・・・・・・・Reaction tank (3
)・・・・・・・・・・・・・・・Substrate (3a)・・
・・・・・・Part where insulating thin film is not formed (8)
・・・・・・・・・・・・Infrared lamp (heating lamp) (9)・・・・・・・・・・・・Insulating thin film αO・・・・・・・・・......W metal thin film (first metal thin film) cIl)...
- W metal thin film (second metal thin film) In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (7)

[Claims] (1) A gas containing at least a metal element is introduced in a sheet-like flow approximately parallel to the surface of the substrate in a reaction tank under reduced pressure, and a gas flow of an inert gas or A first metal thin film containing the metal element is applied to a portion of the substrate on which an insulating thin film is not formed, on which an insulating thin film is formed on a part of the surface while introducing a gas flow mainly consisting of an inert gas. After forming the metal element, a gas containing the metal element and a reducing gas are introduced in a sheet-like flow approximately parallel to the surface of the substrate in the reaction tank, and are arranged so as to face the surface of the substrate. While introducing a gas flow of an active gas or a gas flow mainly composed of an inert gas, the substrate is irradiated with light from a heating lamp, and the difference in light absorption of the insulating thin film substrate and the first metal thin film is detected. A temperature difference is created between the insulating thin film and the first metal thin film, a chemical reaction is caused only on the surface of the first metal thin film, and the metal element is applied to the surface of the first metal thin film. A CVD method characterized by forming a second metal thin film that is sticky. (2) Reducing gas is H_2, gas containing metal elements is W
F_6, MoF_6, TaF_3, CrF_4, TiF
_4, TiCL_6, MoCL_5, WCL_6ALC
The CVD method according to claim 1, characterized in that the gas is any one of metal halides such as L_3 or a combination of two or more thereof. (3) Insulating thin film of SiO_2, Al_2O_3, BSG
, PSG, BPSG, etc., or BN, Si
3. The CVD method according to claim 1 or 2, wherein any one of a nitride such as N_x or a compound such as SiN_xO_y or a combination of two or more thereof is used. (4) The second metal thin film is made of W, Mo, Ta, Cr, Ti,
The CVD method according to any one of claims 1 to 3, characterized in that any one of metals such as Al or an alloy thereof is used. (5) Any one of claims 1 to 4, characterized in that the substrate is made of Si, and at least Si element is exposed on the surface of the substrate where no insulating thin film is formed. CVD method described in the section. (6) The CVD method according to any one of claims 1 to 4, wherein the substrate has a thin film of Si formed on the uppermost layer. (7) Set the wavelength that gives the maximum intensity of the infrared lamp light to 0.
The CVD method according to any one of claims 1 to 6, characterized in that the thickness is 75 to 5 μm.