JP2001319923A - Method for anisotropic etching of base material and apparatus for etching base material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an anisotropic etching method of a base material which makes anisotropic etching possible by casting charged particle beams such as ion beams, or high-speed neutral particle beams such as atomic and molecular beams, on the surface of the base material while an etching gas is brought into contact with the surface of the base material, to increase the activity of a desired part of the surface of the base material, and also provide an apparatus for etching the base material. SOLUTION: In a dry anisotropic etching method, a fluid which is highly reactive with the base material is brought into contact with the surface of the base material to compose a gas containing the constituent elements of the base material using a chemical reaction between the fluid and the base material. With generation of such a gas, the surface of the base material is successively removed. An organic gas [H(hfac)+O2] is used as the fluid highly reactive with the base material. By casting at least one beam selected among ultraviolet rays or laser beam, electron beam or charged particle beam, or atomic beam or molecular beam (Ar ion, Ar radical beam 15, or the like) on a desired part of the surface of the base material, the activity of the part can be locally increased to make anisotropic etching possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anisotropic etching method for a substrate and an apparatus for etching a substrate used for manufacturing a semiconductor device, and more particularly to copper (Cu) as a wiring material for a semiconductor device.
TECHNICAL FIELD The present invention relates to an anisotropic etching method for a substrate and an apparatus for etching a substrate suitable for forming a fine Cu wiring pattern using the same.

[0002]

2. Description of the Related Art High integration of semiconductor devices has progressed, wirings have become finer, and line widths have become smaller. At the order of several μm, Cu, which is excellent in terms of electric resistance, electromigration resistance, and the like, is attracting attention instead of aluminum as a wiring material. However, it is extremely difficult to anisotropically etch Cu (hereinafter, referred to as etching as necessary) by a dry etching method using gas without using a liquid chemical, and it has been put to practical use. No examples are found.

According to a few research cases, SiCl ₄ ,
The result of performing reactive ion etching (RIE) using a mixed gas composed of Cl ₂ , N ₂ and NH ₃ has been reported [Arita et al., Applied Physics, 61, 11 (1992)].
P. 1156]. According to this, as shown in FIG. 1, a favorable processed shape was obtained at an etching rate of about 100 nm / min. Here, NH ₃ is added to the source gas for the purpose of forming a SiN-based protective film on the side wall surface in order to maintain the directionality of the etching. Nevertheless, as shown in FIG. 1, there is a problem that the etching rate decreases as the NH ₃ flow rate increases.

On the other hand, different from the etching of a semiconductor substrate, as a method of removing a copper film adhered inside a chemical vapor deposition (CVD) apparatus of copper, gaseous hexafluoroacetylacetone [C ₅ H] is added to the copper film. ₂ O ₂ F ₆ , hereinafter H (hfa
abbreviated as c)] and contacting oxygen gas to form a vaporizable copper complex compound [Tomoaki Koide et al., Proceedings of the 47th Joint Lecture Meeting on Applied Physics ('00] .
3) 30P-YA-16]. Here, H (hf
ac) Reaction with copper does not occur just by contacting gas,
When O ₂ gas is added to H (hfac) gas, oxidation of metallic copper by the following formula (1), complexation of copper oxide by the following formula (2), and volatilization and removal of the adhered copper film by the reaction of desorption occur. Have been.

[0005] 4Cu + O ₂ → 2Cu ₂ O 2Cu + O ₂ → 2CuO (1) Cu ₂ O + 2H (hfac) → Cu (hfac) ₂ ↑ + Cu + H ₂ O CuO + 2H (hfac) → Cu (hfac) ₂ ↑ + H ₂ O (2)

FIG. 2 is a view showing an actual measurement example of the Cu removal rate reported above. As is clear from FIG.
The copper substrate heated to a temperature of ° C. is etched and removed at a rate of about 400 nm / min. However, if the principle of this report is applied to the etching process of semiconductor device manufacturing as it is, the etching isotropically occurs as shown in FIG.
Significant inconveniences occur in the formation of wiring for semiconductor devices.

In FIG. 3, reference numeral 101 denotes a Si substrate,
An insulating layer 102 and a Cu wiring layer 10 are formed on the surface of the Si substrate 101.
3. A resist layer (mask) 104 is sequentially formed, and H (hfac) gas 10 is applied to the opening 104a of the resist layer 104.
6 is blown to etch the Cu wiring layer 103.
(Hfac) Corrosion holes 105 formed by isotropic etching of gas 106 have openings 1 under resist layer 104.
Since the cross-sectional area of the resist layer 104 is larger and larger than the cross-sectional area of the resist layer 104a, the corrosion hole 105 cannot be formed by being limited to a portion vertically below the opening 104a of the resist layer 104. That is, the Cu wiring layer 103
There is a problem that anisotropic (directional) etching cannot be performed.

[0008]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above points, and is directed to a charged particle such as ions or an atomic / molecular high-speed neutral particle beam while contacting an etching gas with a substrate surface. Is irradiated on the substrate surface, whereby
An object of the present invention is to provide an anisotropic etching method for a substrate and an apparatus for etching a substrate, which enable anisotropic etching by increasing the activity of a desired portion of the substrate surface.

[0009]

According to the first aspect of the present invention, a fluid having good reactivity with the substrate is brought into contact with the surface of the substrate, and the fluid accompanying the chemical reaction is formed between the two. In a dry-etching method of synthesizing a gas containing a base material constituent element and sequentially removing the base material surface, a gas is used as a fluid having a high reactivity with the base material, and the desired It is characterized by locally increasing the activity of the portion to be etched and performing anisotropic etching.

[0010] The invention described in claim 2 is the same as the claim 1.
In the anisotropic etching method of the substrate according to the above, in order to locally increase the activity of the substrate surface, selected from ultraviolet or laser beam irradiation, electron beam or particle beam irradiation, atomic beam or molecular beam irradiation Performing at least one of the operations described above.

As described above, gas is used as a fluid having good reactivity with the substrate, and at least a portion selected from ultraviolet or laser beam, electron beam or charged particle beam, atomic beam or molecular beam at a desired portion of the substrate surface. By irradiating one and locally increasing the activity to perform anisotropic etching, for example, it is possible to perform anisotropic etching of Cu, which has been said to be impossible by dry anisotropic etching. Become.

Further, the invention described in claim 3 is the first invention.
Or the anisotropic etching method of the substrate according to 2, wherein an ion beam, which is a form of a particle beam that locally enhances the activity of the substrate surface, or an atomic beam, or a molecular beam, is used as these particles. The energy is set to be 200 keV or more and 1 keV or less.

As described above, if the energy of these particles is set to 200 keV or more and 1 keV or less using an ion beam, an atomic beam, or a molecular beam, the sputtering of atoms on the surface of the base material is effectively caused, whereby the base is formed. The activity of the particle-irradiated portion on the material surface can be increased.

The invention described in claim 4 is the first invention.
Or in the anisotropic etching method of the substrate according to 2 or 3,
The base material is a substrate in which a copper film for wiring is formed on the surface of a silicon substrate for semiconductor device production, and a desired portion of the surface of the copper film is removed by anisotropic etching to form a fine copper wiring pattern. It is characterized by doing.

By etching the copper film for wiring formed on the surface of the silicon substrate for manufacturing a semiconductor device by the anisotropic etching method according to claim 1 or 2, it becomes impossible conventionally. The anisotropic dry etching of the copper film, which has been performed, becomes possible, and a fine copper wiring pattern can be formed on the silicon substrate.

According to a fifth aspect of the present invention, there is provided a substrate anisotropic etching apparatus for dry anisotropically etching a substrate, comprising a reaction chamber, a particle such as an ion beam or an atomic beam. Equipped with an ion generation / acceleration mechanism to be used as a source of rays and a reactive fluid supply mechanism to supply a reactive fluid having reactivity with the substrate surface, and to a substrate surface arranged at a predetermined position in the reaction chamber. A reactive fluid is supplied from a reactive fluid supply mechanism, and the surface of the substrate is irradiated with a particle beam such as an ion beam or an atomic beam from an ion generation / acceleration mechanism to locally activate a desired portion of the substrate surface. And anisotropic etching is performed.

As described above, the reactive fluid is supplied to the surface of the substrate disposed at a predetermined position in the reaction chamber, and the surface of the substrate is irradiated with an ion beam or an atomic beam to thereby obtain a desired surface of the substrate. By locally increasing the activity of a portion and performing anisotropic etching, for example, etching of a substrate capable of performing anisotropic etching of Cu, which has been said to be impossible by dry anisotropic etching. Device.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. Here, a case will be described in which the H (hfac) gas and the O ₂ gas are supplied in parallel with the particle beam irradiation using the resist provided with the wiring processing pattern as a mask to etch the deposited blanket copper surface. FIG. 4 is a conceptual diagram of the anisotropic etching method for a substrate according to the present invention. In FIG. 4, 11 is Si
And an insulating layer (Si) on the surface of the Si substrate 11.
O ₂ ) 12 and a Cu wiring layer 13 are formed.
Layer 14 provided with a wiring processing pattern on the surface of
Are formed.

Ar ⁺ is formed on the surface of the resist layer 14 of the substrate.
Anisotropic etching is performed by bringing a mixture of H (hfac) gas and O ₂ gas into contact with the substrate while irradiating with the ion or Ar radical beam 15. As a result, the Cu wiring layer 13 in the opening 14a of the resist layer 14 is etched away in a direction perpendicular to the substrate surface, so that a recess can be formed.

This is because the H (hfac) gas and the O ₂ gas adsorbed on the surface of the substrate (Cu wiring layer 13) or staying in the gas phase near the substrate surface have Ar ⁺ ions or A ⁺ ions.
By irradiating r atoms, if the pressure of the gas phase and the energy of the particles of the irradiation beam are adjusted appropriately, the amount of gas components staying in the gas phase attached to the substrate surface is increased, and the gas and By applying energy to the Cu wiring layer 13 or causing sputtering of the irradiated portion of the substrate surface, the reactivity of the irradiated portion can be increased.
In the portion of the Cu wiring layer 13 where the irradiation beam density of Ar ⁺ ions or Ar atoms is high (the bottom of the recess 16), a relatively active reaction occurs as compared with the side wall portion, and as a result, anisotropic etching proceeds. I do.

In FIG. 4, H is used as an etching gas.
A mixture of (hfac) gas and O ₂ gas is used,
However, the present invention is not limited to this. For example, as shown in FIG. 5, it is possible to irradiate the substrate 15 with a beam 15 of oxygen ions or oxygen radicals by using only H (hfac) gas as an etching gas.

FIG. 6 is a conceptual diagram showing the state of etching by the combination shown in FIG. Irradiation with the beam 17 of oxygen ions and oxygen radicals as described above
By supplying (hfac) gas, H (hfa)
c) As a result of the oxygen being supplied intensively to the portion where the irradiation beam density is high on the surface where the molecules are adsorbed, the reaction of Cu → Cu ₂ O → Cu (hfac) ₂ is limited only to the bottom of the concave portion. Occurs, and anisotropic etching of the Cu wiring layer 13 proceeds. In FIG. 6, unlike in the case of FIG. 4, the reaction energy is applied by the beam 17 of oxygen ions or oxygen radicals.

Here, the above document [Tomoaki Koide et al., Proceedings of the 47th Lecture Meeting on Applied Physics ('00 .3) 3
0P-YA-16], H is used as an etching gas.
In the case where (hfac) and oxygen are used, it is considered that it is desirable to first introduce only H (hfac) gas and then add oxygen as a sequence for bringing the gas into contact with the substrate. This is done by first forming H (hfac) on the surface of the Cu wiring layer 13.
Is adsorbed and then oxygen is supplied, it is considered that the substance conversion of the following formula (3) proceeds simultaneously by the action of H (hfac) which is excessively present in the system, thereby realizing a rapid reaction. Can be

Cu → Cu ₂ O Cu ₂ O → Cu (hfac) ₂ (3)

It is said that a temperature equivalent to that of Cu-CVD (170 ° C.) is suitable for causing a reaction by applying only heat instead of the above-described particle energy, but as described above, H
When the (hfac) gas is combined with the beam 17 of oxygen ions or oxygen radicals, the above-described mechanism enables high-speed etching without generation of residues due to products without a temperature raising mechanism. Also, in the case of oxygen beam,
According to the same principle as in the case of the Ar beam, the anisotropy of the etching is realized because the reaction at the bottom of the recess 16 occurs significantly more severely than at the side wall.

As described above, the use of the above-described substrate etching method enables dry anisotropic etching of Cu, which has been practically impossible in the past.

The energy of the particles is desirably 200 eV or more and 1 keV or less. The reason will be described below. FIG. 7 is a diagram showing the energy of the particles and the penetration depth of the particle beam, in which the dominant phenomena occurring on the irradiated surface of the substrate are also shown. When performing sputter cleaning (physical etching) on the base material surface using a normal sputtering apparatus, 200 to 200 g
A having an energy of about 1,000 eV (see FIG. 7)
r ion is used. That is, it can be considered that sputtering of atoms on the substrate surface is caused by using Ar ions having an energy in this range.

Incidentally, when the copper surface is sputtered with, for example, 1,000 eV of Ar ions at an ion current density of 0.85 mA / cm ² , the etching rate of the copper surface is about 34 as a measured value.
nm / min, which is extremely slow [Ryuichi Shimizu and Kazuhiro Yoshiwara, edited by "Practical Auger Electron Spectroscopy", 1989. First Edition Kyoritsu Shuppan Co., Ltd. 233]. Therefore, although it is meaningful to perform Ar ion etching only for dry cleaning of the surface (removal of surface contamination), it is extremely inefficient as a method for shaving the surface into a desired shape and creating a dent. In short, since the etching rate is extremely low, there is no possibility of being applicable to a practical mass-produced processing apparatus.

When the ion beam irradiation causes in-plane non-uniformity due to electric charging on the substrate side or divergence due to electric mutual repulsion of ions,
Instead of ion beam irradiation, a neutral molecular beam or an atomic beam may be applied.

The physical etching rate using only Ar ions, which has been mainly used in conventional research, is described in the above-mentioned document [Practical Auger Electron Spectroscopy, edited by Ryuichi Shimizu and Kazuhiro Yoshihara, 198].
9.6 First Edition Kyoritsu Shuppan Co., Ltd. As shown in [233], a normal value is about 30 nm / min, which is about 400 nm / mi, which is easily obtained by reactive etching (RIE) performed in a semiconductor manufacturing process.
n is significantly lower than n.

As described above, when the surface of copper is etched by the anisotropic etching method for a substrate of the present invention, H (hf
Since the etching by the chemical action of ac) gas and the etching by the physical action of Ar ions occur simultaneously, an etching effect in which the etching by the chemical action and the etching by the physical action are superimposed is obtained.

As mentioned above, the substrate temperature according to FIG.
At 0 ° C., an etching rate of about 400 nm / min can be obtained as an etching rate by the above-mentioned chemical action. Further, when an acceleration voltage of Ar ions is 1.000 V, an etching rate of about 400 nm / min is obtained as an etching rate by the above-mentioned physical action. 30 nm / min can be obtained. Therefore, if the etching by the chemical action and the etching by the physical action operate simultaneously, it becomes possible to easily obtain a value of 10 times or more the etching rate when only the simple Ar ions are used. This provides an epoch-making effect as an anisotropic (directional) etching means for forming Cu wiring.

The anisotropic substrate etching method of the present invention has the following advantages over ordinary plasma etching. The present invention uses conventional dry etching (eg, RI
Unlike E), the substrate is not placed in a plasma environment,
Controlled etching can be performed. When the substrate is placed in the plasma, a chemical reaction occurs between the etching gas and the substrate and the members, generating unnecessary by-products, thereby contaminating the substrate and its surroundings, and causing the etching gas to reach the substrate. As a result of the previous decomposition reaction, the adverse effect of hindering the original etching action is likely to occur.

According to the present invention, a desired etching process can be performed under the condition that the adverse effect of the plasma is completely eliminated as described above. In addition, since an excessive rise in temperature of the substrate surface due to the application of plasma can be avoided, there is an advantage that the subsequent aggregation and granulation of the deposited copper can be suppressed. As described above, according to the method of anisotropic etching of a base material of the present invention, anisotropic dry etching of Cu, which has been almost impossible in the past, is made possible. The contribution is great.

In the above example, Cu is etched as a substrate, but the substrate is not limited to Cu. In short, a fluid having good reactivity with the substrate is brought into contact with the surface of the substrate, and a gas containing the element constituting the substrate accompanying the chemical reaction is synthesized between the two, and the surface of the substrate is sequentially removed with this. A dry anisotropic etching method, using an organic gas as a fluid having good reactivity with the base material, and further applying an ultraviolet or laser beam to a desired portion of the base material surface, an electron beam or a charged particle beam,
If irradiating at least one selected from an atomic beam or a molecular beam to locally increase the activity and perform anisotropic etching,
The substrate is not limited to Cu. In addition, depending on the type of the base material, an inorganic gas other than the organic gas can be used.

FIG. 8 is a view showing a conceptual configuration example of an anisotropic etching apparatus for executing the anisotropic etching method for a substrate according to the present invention. In FIG. 8, reference numeral 20 denotes a reaction chamber.
The base material 22 held by the susceptor 21 is arranged on the upper part of the substrate. The base material 22 is, for example, a substrate having a configuration in which an insulating layer 12, a Cu wiring layer 13, and a resist layer 14 provided with a wiring processing pattern are sequentially laminated on the surface of a Si substrate 11, as shown in FIG. The resist layer 22a formed on the surface of the Cu wiring layer of the base material 22 is disposed facing downward. The susceptor 21 has a heating / cooling mechanism 21a for heating / cooling.

At the lower part of the reaction chamber 20, a high-speed ion generating mechanism 23 for generating an Ar ⁺ ion beam or an Ar atom beam is disposed facing the resist layer 22a of the base material 22. The reaction chamber 20 is connected to a vacuum exhaust system 24. H (hfa) 25 stores H (hfac) gas.
c) a container, and an H (hfac) container 25 is connected to a He reservoir 28 for storing He gas via a mass flow controller (MFC) 26. He reservoir 2
The H (hfac) gas is supplied into the reaction chamber 20 by supplying He gas to the H (hfac) container 25 from 8 via a mass flow controller (MFC) 26. The reaction chamber 20 is supplied from an O ₂ gas source 30 via a mass flow controller (MFC) 29 to an O ₂ gas source 30.
Gas is supplied. Further, Ar gas is supplied to the high-speed ion generating mechanism 23 from an Ar gas source 31.

In the above anisotropic etching apparatus, the reaction chamber 20
When an H (hfac) gas and an O ₂ gas are supplied into the inside and an Ar ⁺ ion beam or an Ar atom beam is irradiated from the high-speed ion generation mechanism 23 toward the substrate 22, as shown in FIG. The H (hfac) gas and the O ₂ gas adsorbed on the surface or staying in the gas phase near the surface of the substrate 22 are given energy from Ar ⁺ ions or Ar atoms. Here, at the bottom of the concave portion of the substrate where the irradiation density of the Ar ⁺ ion or Ar atom beam of the Cu wiring layer of the substrate 22 becomes high, a relatively active reaction occurs as compared with the side wall portion. I do.

FIG. 9 is a view showing another conceptual configuration example of an anisotropic etching apparatus for performing the anisotropic etching method for a substrate according to the present invention. In FIG. 9, the portions denoted by the same reference numerals as those in FIG. 8 indicate the same portions. The anisotropic etching apparatus of FIG. 9 is different from that of FIG. 8 in that an ion neutralizing mechanism 32 for electrically neutralizing ions is disposed above the high-speed ion generating mechanism 23. The high-speed ion generating mechanism 23 has an O ₂ gas source 33.
Is supplied with O ₂ gas. Anisotropic etching in the anisotropic etching apparatus having the above configuration is the same as that shown in FIG.

By using the ion neutralizing mechanism 32 for electrically neutralizing ions as described above, it is easy to increase the diameter of the apparatus. That is, when a charged particle beam such as an ion beam is used, the individual particles have the same polarity of charge, and therefore tend to repel each other when the flight distance of the beam is long, as is often the case with a large-diameter device. . as a result,
As shown in FIG. 10A, the inclination in the etching direction is likely to increase on the outer peripheral side of the base material 22. On the other hand, if a neutral particle beam generated by neutralizing ions is used, the irradiation direction is maintained parallel as shown in FIG. It is easy to manufacture the device. Further, since the irradiated particles are electrically neutral, damage due to excessive charging of the substrate 22 can be avoided.

[0041]

As described above, according to the invention described in each claim, the following excellent effects can be obtained.

According to the first and second aspects of the present invention, gas is used as a fluid having high reactivity with the substrate, and the activity of a desired portion on the surface of the substrate is locally increased to perform anisotropic etching. By doing so, for example, anisotropic etching of Cu, which has been said to be impossible in dry anisotropic etching, becomes possible.

According to the third aspect of the present invention, an ion beam, an atomic beam, or a molecular beam for locally increasing the activity of a desired portion on the surface of the substrate is used as the energy of these particles. Is set to 200 keV or more and 1 keV or less, sputtering of atoms on the substrate surface can be effectively caused.

According to the fourth aspect of the present invention, the copper film for wiring formed on the surface of the silicon substrate for manufacturing a semiconductor device is etched by the anisotropic etching method according to the first, second or third aspect. By engraving, it becomes possible to dry-etch a copper film, which has been impossible in the past, and a fine copper wiring pattern can be formed on a silicon substrate.

According to the fifth aspect of the present invention, the reactive fluid is supplied to the surface of the substrate disposed at a predetermined position in the reaction chamber, and the surface of the substrate is irradiated with an ion beam or an atomic beam. By locally increasing the activity of the desired portion of the base material surface and performing anisotropic etching, for example, anisotropic etching of Cu, which has been said to be impossible to dry anisotropic etching until now, A possible substrate etching apparatus can be provided.

[Brief description of the drawings]

1 shows the effect of S on the reactive ion etching rate of Cu
iCl ₄ . Cl ₂ . FIG. ₃ is a diagram showing the effect of adding NH ₃ to a N ₂ mixed gas.

FIG. 2 is a view showing an actual measurement example of a removal rate of Cu by H (hfac) + O ₂ gas.

FIG. 3 is a conceptual diagram illustrating isotropic etching using H (hfac) + O ₂ gas.

FIG. 4 shows anisotropic etching (etching) of a substrate according to the present invention.
Gas = H (hfac) + O _Two, Particle beam = Ar y
FIG. 3 is a conceptual diagram for explaining (on or Ar radical).
You.

FIG. 5 is a diagram showing an example of a combination of an etching gas and a particle beam used for anisotropic etching of a substrate according to the present invention.

FIG. 6 is a conceptual diagram for explaining anisotropic etching (etching gas = H (hfac), particle beam = oxygen ions or oxygen radicals) of a substrate according to the present invention.

FIG. 7 is a diagram showing the energy of particles and the depth of penetration into a surface to be irradiated by particle beam irradiation.

FIG. 8 is a diagram showing an example of a conceptual configuration of an anisotropic etching apparatus that executes the anisotropic etching method for a base material according to the present invention.

FIG. 9 is a diagram showing a conceptual configuration example of an anisotropic etching apparatus for executing the anisotropic etching method for a base material according to the present invention.

FIG. 10 is a conceptual diagram for explaining a tendency of etching by an ion beam and a neutral particle beam.

[Explanation of symbols]

Reference Signs List 11 Si substrate 12 Insulating layer (SiO ₂ ) 13 Cu wiring layer 14 Resist layer 15 Ar ion or Ar radical beam 16 Depression 17 Oxygen ion or oxygen radical beam 20 Reaction chamber 21 Susceptor 22 Base material 23 High-speed ion generating mechanism 24 Vacuum exhaust system 25 H (hfac) container 26 Mass flow controller (MFC) 28 He reservoir 29 Mass flow controller (MFC) 30 O ₂ gas source 31 Ar gas source 32 Ion neutralization mechanism 33 O ₂ gas source

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yuji Araki 11-1 Haneda Asahimachi, Ota-ku, Tokyo Ebara Corporation (72) Inventor Hiroshi Nagasaka 4-2-1 Motofujisawa, Fujisawa City, Kanagawa Prefecture (72) Inventor Momoko Kadoya 4-2-1 Motofujisawa, Fujisawa-shi, Kanagawa F-term (reference) 4K057 DA11 DA12 DA13 DD04 DD05 DD06 DD08 DE14 DE20 DN01 5F004 AA02 AA05 BA11 BA19 BB01 BB02 BB03 DA00 DA22 DA23 DA26 DB08 EB02

Claims (5)

[Claims] 1. A substrate and a fluid having good reactivity with the substrate are brought into contact with the surface of the substrate, and a gas containing the element constituting the substrate accompanying a chemical reaction is synthesized between the two. In the dry etching method of sequentially removing, using a gas as a fluid having a good reactivity with the base material, further locally increasing the activity of a desired portion of the base material surface and performing anisotropic etching. Characteristic anisotropic etching method for substrates. 2. The anisotropic etching method for a substrate according to claim 1, wherein the activity of the surface of the substrate is locally increased by irradiating an ultraviolet ray or a laser beam, irradiating an electron beam or a particle beam, A method of anisotropically etching a substrate, wherein at least one selected from irradiation of an atomic beam or a molecular beam is performed. 3. The anisotropic etching method for a substrate according to claim 1 or 2, wherein the ion beam or the atomic beam is one form of a particle beam that locally increases the activity of the surface of the substrate. Using a molecular beam, the energy of these particles is 1 at 200 eV or more.
An anisotropic etching method for a substrate, wherein the method is keV or less. 4. The method for anisotropically etching a substrate according to claim 1, wherein the substrate is a substrate having a copper film for wiring formed on a surface of a silicon substrate for manufacturing a semiconductor device. A method of anisotropically etching a substrate, comprising removing a desired portion of the surface of the copper film by the anisotropic etching to form a fine copper wiring pattern. 5. An anisotropic etching apparatus for a substrate for dry anisotropic etching of a substrate, comprising: a reaction chamber; and an ion generating and / or ion generating source used as a source of a particle beam such as an ion beam or an atomic beam. An acceleration mechanism, and a reactive fluid supply mechanism that supplies a reactive fluid having reactivity with the substrate surface, wherein the reactive fluid supply mechanism reacts with the substrate surface disposed at a predetermined position in the reaction chamber. While supplying an anaerobic fluid, the surface of the substrate is irradiated with a particle beam such as an ion beam or an atomic beam from the ion generation / acceleration mechanism to locally increase the activity of a desired portion of the substrate surface and anisotropically etch the substrate. An apparatus for etching a substrate, wherein the apparatus performs engraving.