JPH08203873A - Plasma processing device - Google Patents

Abstract

(57) [Summary] [Purpose] Especially, it has excellent basic characteristics, processing characteristics, and low damage during etching or film formation of large-diameter wafers, and long-term reliability of high-frequency power supply system consisting of spiral coil and capacitor. To provide an improved inductively coupled plasma processing apparatus. A chamber 18 in which a plasma-processed object is housed, a spiral coil 28 disposed outside the chamber 18, a spiral coil 28 disposed in parallel with the spiral coil 18 in close proximity, A plasma processing apparatus having a certain dielectric window portion 22 and a dielectric window portion 22 in which a magnet member 24 is integrated. The magnet member 24 is integrated with the dielectric window portion 22 so as to generate a multipolar magnetic field having a recoil action of electrons. Magnet member 2
Reference numeral 4 is integrated with the dielectric window portion 22 so as to compensate for the sparse and dense distribution of the induced electric field or electron density inside the plasma generated inside the chamber.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma processing apparatus such as a plasma etching apparatus and a plasma CVD apparatus used, for example, in the field of manufacturing semiconductor devices, and more specifically, to the uniformity and variation of etching of a large diameter wafer. The present invention relates to a plasma processing apparatus having an anisotropic process controllability, low damage property, and excellent film formation uniformity.

[0002]

2. Description of the Related Art Higher integration and densification of devices and higher performance and integration of devices, which are realized by current highly integrated semiconductor circuits such as VLSI and ULSI, are further advanced. For this, several technical methods have been found. For example, miniaturization of device dimensions by high integration technology, increase of chip dimensions by high density technology, or improvement of device structure or circuit. In these directions, semiconductor manufacturing equipment that bears process / production technology, especially plasma etching equipment or plasma C
VD devices are expected to have some performance improvements.

For example, improvement of basic characteristics such as controllability of fine processing having anisotropy and small dimensional conversion difference, processing speed for large diameter wafers, processing uniformity, selectivity, etc.,
Improvements such as reduction of plasma damage that correlates with device yield are expected.

In recent years, in order to obtain these improvements in performance, a plasma source capable of generating plasma at a high density (electron / ion density in the plasma is 1 × 10 ¹² / cm ³ or more) is mounted. Etching / CVD equipment has been proposed and is being applied to process / manufacturing technology. For example, an ECR plasma type device using a plurality of strong magnetic field coils, a helicon wave plasma type device using a helicon wave belonging to a whistler mode that can propagate in plasma, and an inductively coupled plasma using a spiral coil / helical coil. There is an inductively coupled plasma type device for generating the. In all of the apparatuses, the ion species generated at high density promoted the etching reaction with the material to be deposited, and as a single-wafer apparatus, a high-speed etching process that contributes to the productivity has been obtained.

In particular, inductively coupled plasma etching / CVD utilizing RF high frequency which is a conventional commercial frequency.
The device is relatively easy to simplify the device configuration and can generate high-density plasma, so in the semiconductor device manufacturing field,
Its application is expected. This device is characterized by a spiral coil (spiral coil) arranged on the upper surface of the dielectric window and an approximately closely-spaced electrode structure including an independently controlled lower radio frequency (RF) power source. In this device, the main components inside the vacuum chamber can also be made of a dielectric material, which is useful for cleaning and regeneration of the device.

Further, by increasing the number of turns of the spiral coil on the upper surface, it is possible to easily cope with a large diameter wafer.
Large area plasma processing can be enabled. These coils generate an induced electric field E due to a change in magnetic flux density B with time.
Is generated (Faraday's law), the induced electric field E is
It is distributed in a plane along the coil.

The induction electric field E causes acceleration of electrons and Joule heating to generate a planar plasma. In this plasma generation system, if the RF angular frequency ω and the L and C matching circuits satisfy the resonance condition, the power applied to the upper coil is set to a high power above a certain threshold, so-called low density discharge: E- High density plasma (e ⁻ ≧ 1 × 10 ¹² / cm ³ ) transitionally from discharge (or capacitively coupled plasma discharge) to high density discharge: H-discharge (or inductively coupled plasma discharge) It is possible to

Since the high-density plasma is formed in a planar shape and the ion species are independently extracted by the RF bias of the lower electrode, etching excellent in basic characteristics such as in-plane uniformity of the wafer can be achieved relatively easily. Has been done. In the Al alloy etching with a 6-inch diameter wafer, the in-plane uniformity is ± 5.0% or less, and the in-wafer uniformity is ± 5.0%.
It has good characteristics such as 5.0% or less. However, in order to improve the uniformity, it is a precondition that a focus ring (reference numeral 35 shown in FIG. 1) is attached to the outer periphery of the lower electrode.

[0009]

As described above, in the inductively coupled plasma processing apparatus using the spiral coil, it is relatively easy to improve the basic etching characteristics required for a large-diameter wafer, and the apparatus configuration is also high. Since it is simplified, it has a useful aspect in semiconductor device manufacturing. However, strictly speaking, this device may present some disadvantages.

The induced electric field E formed by a coil electrode composed of a single spiral coil, an element consisting of a variable capacitor connected in series, and an RF power source was numerically analyzed by the finite element method centered on the Maxwell equation. The results are shown in Fig. 8. As shown in FIG. 8, it can be understood that the induction electric field E vector is generated in a spiral shape along the winding direction of the spiral coil 50. The induced electric field E vector is indicated by an arrow in the figure, and the larger the arrow, the stronger the vector strength.

As shown in FIG. 8, the strength of the vector (absolute value of electric field strength) is weakened in the center and outermost peripheral regions. The density is caused by, for example, the magnetic flux affected by the chamber wall surface at the outermost circumference or the divergence / attenuation of the induction electric field E. In the sparse electric field distribution between the center of the coil electrode and the outermost peripheral region, the distribution of ion species and electrons generated in the bulk plasma is non-uniform.

In particular, when components such as a focus ring are not used, the in-plane uniformity of the wafer deteriorates because the flux (bundle) of the ion species contributing to etching tends to be sparse in the outer peripheral region. For example, in Al alloy etching with a 6-inch diameter wafer, the in-plane uniformity of the wafer is ± 6% or more, and the distribution is obviously poor.
Therefore, in order to improve the uniformity of Al alloy etching with a 6-inch wafer, it is necessary to mount the focus ring that has been conventionally used.

However, when the focus ring is placed, residual chlorine Cl, which is a by-product at the time of etching,
Polymers containing carbon C, nitrogen N, boron B, etc. are deposited on the surface of the focus ring, and contamination of the wafer surface due to deterioration of dust due to re-desorption becomes a problem, resulting in problems such as reduction in manufacturing yield in mass production. appear.

Further, in order to deal with a large diameter wafer having a diameter of 8 inches or more, in an inductively coupled plasma source using a single spiral coil or the like, it is common to increase the number of turns of the spiral coil and the size of the coil. Is.
With these improvements, it is possible to easily set a coil configuration suitable for a large diameter wafer. However, in reality, as the size of the coil increases, a parasitic capacitor is generated between the coupling circuit composed of the coil and the variable capacitor and the ground portion (ground), and the capacitance thereof increases.

The self-inductor L of the coil is typically ~ 2
When the RF power supply of 13.56 MHz is used, the capacitance C of the variable capacitor that satisfies the resonance of the coupling circuit is approximately 70 pF. Here, it is necessary to consider a capacitance of the order of 10 pF as the parasitic capacitor. This parasitic capacitance disturbs the matching of the coupling circuit and hinders resonance at 13.56 MHz. These mismatches cause damage to the coil, the variable capacitor, and the matching circuit, and are regarded as problems.

The present invention has been made in view of such circumstances, and in particular, it is excellent in basic characteristics, processing characteristics, and low damage during etching or film forming processing of a large-diameter wafer, and has a high frequency including a spiral coil and a capacitor. An object of the present invention is to provide an inductively coupled plasma processing apparatus in which the long-term reliability of the power supply system is improved.

[0017]

In order to achieve the above object, a plasma processing apparatus (a plasma CVD apparatus, a plasma etching apparatus, etc.) according to the present invention comprises a chamber in which a plasma processing object is housed, A spiral coil disposed outside the chamber, a dielectric window portion that is disposed in parallel with the spiral coil and is close to the spiral coil, and is a part of the chamber, wherein a magnet member is integrated. And a section.

It is preferable that the magnet member is integrated with the dielectric window so as to generate a multipolar magnetic field having a recoil action of electrons. It is preferable that the magnet member is embedded in an accommodation hole formed inside the chamber of the dielectric window portion, and the inside of the chamber of the accommodation hole in which the magnet members are embedded is closed by a plug.

It is preferable that the plug is made of an anodized aluminum thin plate, an alumite ceramic treated aluminum thin plate, or a thin plate made of the same material as the dielectric window portion. It is preferable that the magnet member is integrated with the dielectric window portion so as to compensate the induced electric field or the electron density distribution in the plasma generated in the chamber.

It is preferable that the magnet members are densely arranged in a region around the center of the spiral coil and an outer peripheral region. It is preferable that the magnet members are radially and dispersed so as not to prevent the magnetic flux generated by the spiral coil from entering the chamber.

In order to independently control the incident energy of the ion species generated in the plasma in the chamber, it is preferable to have an independent high frequency power source for the lower electrode, separately from the high frequency power source for the spiral coil. .

[0022]

The induced electric field E in the inductively coupled plasma processing apparatus has a spiral induced electric field E vector along the winding direction of the spiral coil. The distribution of the E vector has a sparse / dense distribution due to the magnetic flux affected by the chamber wall at the outermost circumference, the divergence / attenuation of the induction electric field E, or the like. In the electric field distribution having this sparse and dense distribution, the distribution of the ion species generated inside the bulk plasma and the distribution of the electrons are also non-uniform.

When a single spiral coil and a single dielectric window are used, the induction electric field E and the electron density have a concentric circular density distribution and nonuniformity. However, in the case of the present invention, since the magnet member is integrated with the dielectric window so as to generate a multi-pole magnetic field, the recoil action of electrons generated in plasma by the cusp magnetic field formed by the magnet member. However, it works effectively for bulk plasma. Since these magnet members are preferably radially arranged so as to reduce the sparse / dense distribution of the induction electric field E and the electron density, they are more effective.

Usually, there is an influence of the induced electric field E on the bulk plasma up to the skin depth σ = c / ω _pe, and to the same degree,
There is a sparse and dense distribution of electron density. Note that c = 2.997
925 × 10 ⁸ m / sec, ω _pe is the plasma frequency of electrons (rad / sec), and normal σ is 1 to 3 cm. In the present invention, the magnetic flux of the magnet members arranged in multiple poles,
By selecting a certain value, it is possible to adjust the recoil distance / range of the electrons. Since there is a compensation effect from these axial directions (plasma is locally confined), the distribution of electrons and ionic species in the plasma also tends to be uniform in the radial direction.

Therefore, the uniformity of ion species and electron density in the plasma is improved over the entire surface of the wafer. By these improvements, basic etching characteristics such as in-plane uniformity of wafer, processing characteristics, or film formation characteristics are significantly improved. Further, since the density distribution of ion species and electrons in the bulk plasma is improved, electrical damage to the wafer on which a fine high-density transistor element or the like is being formed is reduced.

When an 8-inch diameter wafer is subjected to plasma processing, the parasitic capacitor increases as the diameter of the spiral coil increases, and the effect on LC resonance cannot be ignored. In the present invention, the number of turns of the coil is increased (including an increase in the size of the coil) by adjusting the dispersed arrangement state of the magnet members integrally formed in the dielectric window portion or the magnetic flux.
It is possible to reduce Therefore, it is possible to suppress an increase in the capacitance of the parasitic capacitor. Also, the burden on the integrity of the coupling circuit is reduced. It is also useful from the viewpoint of long-term reliability of the high frequency power supply system.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A plasma processing apparatus according to the present invention will be described below in detail with reference to the embodiments shown in the drawings. FIG. 1 is a view showing a cross section of a main part of an inductively coupled plasma etching apparatus according to an embodiment of the present invention, FIG. 2 is a perspective view of a dielectric window part shown in FIG. 1, and FIG. 3 is a II-II shown in FIG. FIG. 4 (A) is a cross-sectional view of the main part along the line, FIG.
5C is a diagram showing an example of multipole arrangement, FIG. 5A is a graph showing an electron density distribution in the case of the embodiment of the present invention, and FIG. 5B is a graph showing an electron density distribution in the case of the conventional example. 6 and 7 are views showing an example of arrangement of magnet members according to another embodiment of the present invention.

First, an inductively coupled plasma etching apparatus according to an embodiment of the present invention shown in FIGS. 1 to 4 will be described. As shown in FIG. 1, the inductively coupled plasma etching apparatus 1 according to the present embodiment has a chamber 18 in which a mounting plate 4 on which a semiconductor wafer 2 to be plasma-etched is mounted is installed. The surface of the mounting plate 4 is anodized. Since the mounting plate 4 consumes surface treatment such as plasma cleaning, it can be replaced with a spare part.

The chamber 18 is made of, for example, stainless steel. The mounting plate 4 is mounted on the top of the ceramic support 6. An inner chamber 8 is attached to the outer circumference of the support 6. A lower high frequency power supply conductor 10 is attached to the center of the support 6. The conductor 10 includes a coupling capacitor 14 and a radio frequency (RF) power supply 1.
6 is connected. The RF power supply 16 is provided separately from the power supply 32 described below and can generate an RF bias. A cooling passage 12 is formed in the support 6 and the mounting table 4. A cooling gas flows through the passage 12 to cool the wafer 2. As the cooling gas, for example, helium He or the like is used. The cooling gas directed to the back surface of the wafer 2 through the passage 12 is
It is supplied to the back surface of the wafer 2 from a groove or a fine hole formed in the mounting plate 4. The pressure of this cooling gas is controlled. Since the cooling gas is uniformly diffused on the back surface of the wafer 2, the heat exchange efficiency is improved and the heat storage of the wafer 2 can be prevented. To bring the wafer 2 into close contact with the mounting plate 4, a general electrostatic chuck method is used.

The mounting plate 2, which is also a lower electrode, is electrically insulated from the inner chamber 8 by a ceramic support 6 which is an insulator. Therefore, the bias application by the lower RF power source 16 can be accurately realized. Since the plasma etching apparatus is used in this embodiment, the inside of the ceramic support 6 is filled with a cooling medium to cool the support 6. When the apparatus 1 is used as a plasma CVD apparatus, a halogen lamp or a heater, which is a wafer heating mechanism, can be installed inside the support 6. Further, in the case of the plasma CVD apparatus, the lower RF power source 16 and the coupling capacitor 14 may not be mounted.

A gas inlet 20 is attached to the outer periphery of the upper portion of the chamber 18. An etching gas or the like is introduced from the gas inlet 20. Further, a dielectric window portion 22 is mounted on the upper portion of the chamber 18. The dielectric window portion 22 is made of a raw material such as alumina ceramic or quartz. The chamber 18 and the inner chamber 8 are
The inside is sealed with a vacuum seal or the like, a mixed etching gas whose flow rate is controlled is introduced from the inlet 20, and a desired internal pressure is obtained by a vacuum pump. Dielectric film 22 and mounting plate 4
The distance t between the and is adjustable by a moving means (not shown), but is on the order of several cm to several tens of cm.

Outside the dielectric window portion 22, this window portion 22 is provided.
A spiral coil 28 is arranged substantially parallel to the.
The spiral coil 28 is made of a conductor material (eg, copper) having a winding resistance R and a self-inductance L. A variable capacitor 30 and a radio frequency (RF) power source 32 are connected in series to the spiral coil 28. The change of the magnetic field by this spiral coil 28 is
It is transmitted to bulk plasma through the dielectric window portion 22.

In this embodiment, as shown in FIGS. 2 to 4, the magnet member 24 is integrally embedded in the dielectric window portion 22. The magnet member 24 is made of, for example, a ferromagnetic material that generates a magnetic flux. In this embodiment, as shown in FIG. 4 (A), the magnet member 24 is composed of an inner peripheral side magnet member 24a and an outer peripheral side magnet member 24b, and the induced electric field or electron density of the plasma generated inside the chamber is reduced. The area around the center of the spiral coil to compensate for the sparse and dense distribution,
They are densely arranged in the outer peripheral region. Moreover, the magnet member 2
4 are arranged radially and in a distributed manner so as not to prevent the magnetic flux generated by the spiral coil from entering the chamber.

In the present embodiment, these magnet members 24 constitute a multi-pole magnet, and as shown in FIG. 4 (B) or (C), N poles and S poles are arranged alternately. Has become. As shown in FIG. 4A, the inner peripheral side magnet member 24a
Are arranged radially and not in the center thereof. The diameter d of the central region where these magnet members 24a are not arranged is
Although not particularly limited, it is, for example, about 5 to 10 cm. Further, the width ba of the pair of inner circumferential side magnet members 24a is NS.
Is NS and the width bc of the pair of outer peripheral side magnet members 24b.
Although not particularly limited, it is about 1 to 5 cm.

The length La in the longitudinal direction of the inner magnet member 24a and the length Lb in the longitudinal direction of the outer magnet member 24b are substantially equal, and their lengths are not particularly limited.
For example, when the radius of the dielectric window portion 22 is r, the length is 10 to 30% of the radius r. Further, the radial length Lc of the region formed between the inner peripheral side magnet member 24a and the outer peripheral side magnet member 24b in which the magnet member is not arranged is
The length is 40 to 80% with respect to the radius r of the dielectric window portion 22.

The individual magnetic flux densities and the number of the magnetic members 24 arranged are determined by how many multipole magnetic fields can be formed on the inner peripheral side and the outer peripheral side as a whole.
As an example, it is preferable that the strength of the multipole magnetic field by the inner peripheral side magnet member 24a is 10 to 200 Gauss, and the strength of the multipole magnetic field by the outer peripheral side magnet member 24b is 10 to 200 Gauss.

As shown in FIG. 3, these magnet members 24 are embedded in an accommodation hole 25 formed inside the chamber of the dielectric window portion 22, and the inside of the chamber of the accommodation hole 25 is closed by a plug 26. I am doing it. The plug 26 is formed of an anodized aluminum thin plate, an alumite ceramic treated aluminum thin plate, a thin plate made of the same material as the dielectric window portion, and the like so as to allow the magnetic flux to pass therethrough.

As shown in FIG. 1, in the device 1 of this embodiment, the spiral coil 28 arranged substantially parallel to the outside of the dielectric window portion 22 is used as an RF drive electrode. Further, the wafer mounting plate 4 itself, which is the lower electrode, is also used as an RF biased cathode electrode. Gas inlet 2
0, an etching gas is introduced, the inside of the chamber 18 is evacuated by a vacuum pump, and a vacuum state is obtained with a desired etching gas composition. In this state, plasma is generated with the same gas species. By applying high power equal to or higher than the threshold value to the spiral coil 28, high density plasma having an e ⁻ belonging to ICP (inductively coupled plasma) of 1 × 10 ¹² / cm ³ or more is obtained.

In this embodiment, since the magnet members 24 for generating a multi-pole magnetic field are integrated in the dielectric window portion 22 so as to be dispersed, the magnet members 24 are separated from the magnetic field generated by the spiral coil 28. Cusp-like magnetic field (lines of magnetic force)
Occur inside the chamber of the dielectric window portion 22. In the chamber axial direction, the action of recoiling e ⁻ effectively works, and the loss due to recombination of e ^{− on} the lower surface of the window is reduced. By the function of alleviating the density of the electron density, the electron density distribution in the chamber axial direction and the radial direction inside the plasma becomes more uniform.

When a spiral coil driven by an RF power source is used by using the dielectric window portion 22 having the distributed multipole magnets according to this embodiment, it is generated inside the bulk plasma generated in the chamber 18. An example of the radial electron density distribution is shown in FIG. For comparison, a conventional example in which the electron density distribution in the radial direction generated in the bulk plasma was obtained in the same manner except that a single dielectric window portion in which a multi-pole magnet was not used was used is shown in FIG. Shown in.

As shown in FIG. 5, in the conventional example using a single dielectric window portion without using a multi-pole magnet, the nonuniformity of the induction electric field E affects and the electron density distribution in the radial direction is also nonuniform. is there.
On the other hand, in the present embodiment using the dielectric window portion in which the multi-pole magnets are dispersedly arranged, the density of plasma in the chamber axial direction and the radial direction is relaxed, so that the uniformity of the electron density distribution in the radial direction is particularly improved. .

As a result, the plasma density in the radial direction of the wafer is made uniform, and a good sheet-shaped plasma is generated. Therefore, various characteristics such as etching basic characteristics such as wafer in-plane uniformity, processing characteristics, and low damage characteristics are improved. Next, an example of improving the basic characteristics during Al etching will be shown.

As a basic characteristic, Al (1.0%)-using a resist-patterned 8-inch diameter wafer was used.
The etching rate of the Si (0.5%)-Cu alloy and the in-plane uniformity of the wafer were examined. The plasma etching apparatus 1 of the present embodiment having the dielectric window portion 22 in which the multi-pole magnet is arranged shown in FIGS. 1 to 4 and the plasma etching apparatus of the conventional example having the single dielectric window portion in which the multi-pole magnet is not arranged. Then, the etching rate and the in-plane uniformity of the wafer were compared under the same etching conditions shown in Table 1 below.

[0044]

[Table 1]

In the conventional apparatus, the etching rate is 1
While it was 210 nm / min ± 6.8%, it was 1320 nm / min ± 4.8% in the device of this example. In the apparatus of the present embodiment, the average etching rate is improved as compared with the conventional apparatus, and the in-plane uniformity of the wafer is a value suitable for large-diameter wafer processing (≦ 5.0.
%) Has been confirmed. Therefore, unlike the conventional case, there is no problem caused by inserting the focus ring 35 shown in FIG.

In addition, when the processing controllability during Al alloy etching in the apparatus of this embodiment was also investigated,
It is possible to obtain the shape control (anisotropic) of the wiring pattern at a half micron level (line width L ≦ 0.5 μm) or less.
According to the present embodiment, by using the inductively coupled plasma etching apparatus having the dielectric window portion 22 in which the multi-pole magnets are dispersedly arranged, basic characteristics such as etching uniformity and processing controllability such as anisotropy are improved. In addition, it is possible to obtain process performance with low damage to the microfabricated transistor element.

The present invention is not limited to the above-mentioned embodiments, but can be variously modified within the scope of the present invention. For example, the arrangement of multi-pole magnets is as shown in FIGS.
4 is not limited to the embodiment shown in FIG. 4, the magnet member 34 may be replaced by a dot-shaped inner peripheral side magnet member 34a as shown in FIG.
And a dot-shaped outer circumference side magnet member 34b, which are arranged around the center of the spiral coil and the outer circumference so as to compensate for the density distribution of the induced electric field or electron density inside the plasma generated inside the chamber. The areas may be densely arranged. Moreover, these magnet members 34
Are distributed and arranged so as not to prevent the magnetic flux generated by the spiral coil from entering the chamber.

Further, as shown in FIG. 7, the magnet member 44
Is composed of a ring-shaped inner peripheral side magnet member 44a and a ring-shaped outer peripheral side magnet member 44b, and these are configured to compensate for the sparse and dense distribution of the induction electric field or electron density inside the plasma generated inside the chamber. In addition, the spiral coil may be densely arranged in the peripheral region and the central peripheral region. Moreover, these magnet members 44 are dispersedly arranged so as not to prevent the magnetic flux generated by the spiral coil from entering the chamber.

The arrangement and arrangement of these multi-pole magnets also have the same effect as that of the above embodiment. The etching target film processed by the etching apparatus according to the embodiment of the present invention is an Al alloy film (including a laminated film of a refractory metal such as W) applied to multilayer wiring of a semiconductor device, Cu, Ag. , Au
In addition to metal films such as the above, an insulating film mainly composed of a silicon dioxide film (SiO ₂ ) forming the interlayer insulating film, a refractory metal silicide film applied as a gate electrode, or a polycide film (WSix _). / Poly-S
i, etc. TiSi _x / Poly-Si), may be an salicide film.

Further, the plasma processing apparatus according to the present invention is
The plasma etching apparatus is not limited to the plasma etching apparatus, and the plasma C
The VD device can be similarly applied. CVD subject to the plasma CVD apparatus according to the present embodiment
The film is not particularly limited, but various films that can be thinned and are used in the field of highly integrated semiconductor devices are exemplified.

[0051]

As described above, according to the plasma processing apparatus of the present invention, the etching uniformity (or one of the basic characteristics of the CVD film formation) of a wafer whose diameter is increasing is formed. Uniformity) and the controllability of processing such as anisotropy. further,
It is possible to realize process performance with low damage to a microfabricated transistor element or the like.

[Brief description of drawings]

FIG. 1 is a diagram showing a cross section of a main part of an inductively coupled plasma etching apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view of the dielectric window portion shown in FIG.

FIG. 3 is a cross-sectional view of relevant parts taken along the line II-II shown in FIG.

4A is a diagram showing an arrangement example of a magnet member, FIG.
(B), (C) is a figure which shows the example of multipole arrangement.

5A is a graph showing an electron density distribution in the case of the embodiment of the present invention, and FIG. 5B is a graph showing an electron density distribution in the case of the conventional example.

FIG. 6 is a view showing an arrangement example of magnet members according to another embodiment of the present invention.

FIG. 7 is a diagram showing an arrangement example of magnet members according to still another embodiment of the present invention.

FIG. 8 is a diagram showing a numerical analysis example of an induction electric field E formed by a single spiral coil to which RF power is applied by a finite element method.

[Explanation of symbols]

 2 ... Wafer 4 ... Mounting plate 6 ... Support 8 ... Inner chamber 10 ... Lower high frequency power conductor 12 ... Cooling passage 14 ... Coupling capacitor 16 ... High frequency power 18 ... Chamber 20 ... Gas inlet 22 ... Dielectric window 24 , 34, 44 ... Magnet member 25 ... Housing hole 26 ... Plug body 28 ... Spiral coil 30 ... Variable capacitor 32 ... High frequency power supply 35 ... Focus ring

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication H01L 21/304 341 D H05H 1/46 A 9216-2G

Claims (8)

[Claims] 1. A chamber in which an object to be plasma-processed is housed, a spiral coil arranged outside the chamber, a spiral coil arranged close to and parallel to the spiral coil, and a part of the chamber. A plasma processing apparatus having a certain dielectric window part, which is integrated with a magnet member. 2. The plasma processing apparatus according to claim 1, wherein the magnet member is integrated with the dielectric window portion so as to generate a multipolar magnetic field having a recoil action of electrons. 3. The magnet member is embedded in an accommodation hole formed inside the chamber of the dielectric window portion, and the inside of the chamber of the accommodation hole in which the magnet members are embedded is
The plasma processing apparatus according to claim 1 or 2, which is closed with a plug. 4. The plug according to claim 3, wherein the stopper is made of an anodized aluminum thin plate, an alumite ceramic treated aluminum thin plate, or a thin plate made of the same material as the dielectric window portion. Plasma processing equipment. 5. The magnet member is integrated with the dielectric window portion so as to compensate for an induced electric field or a density distribution of electron density in plasma generated inside the chamber. The plasma processing apparatus according to claim 1. 6. The plasma processing apparatus according to claim 5, wherein the magnet members are densely arranged in an area around the center of the spiral coil and an area around the outer circumference of the spiral coil. 7. The magnetic members are radially and dispersedly arranged so as not to prevent the magnetic flux generated by the spiral coil from entering the chamber.
7. The plasma processing apparatus according to any one of 6 to 6. 8. A plasma having an independent high frequency power supply for the lower electrode, separately from the high frequency power supply for the spiral coil, for independently controlling the incident energy of the ion species generated in the plasma in the chamber. Processing equipment.