JP2002329716A - Plasma processing apparatus, plasma processing method and method for manufacturing element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plasma processing apparatus which can stably and uni formly generate of high electron density low electron temperature a plasma even in the center, and to provide a plasma processing method. SOLUTION: In the plasma processing apparatus comprising a means for holding an object in a plasma process chamber, a means for introducing a gas into the plasma process chamber, a means for exhausting the plasma process chamber, and a means for introducing a microwave for generating a plasma into the plasma process chamber through a waveguide having slots 114 and a dielectric window, the slots 114 are circular and provided with a predetermined angular interval and a predetermined opening angle by punching on a plurality of concentric circles having different radii on the surface in parallel to the microwave magnetic field surface 121 of the waveguide. Where n1 is the number (odd number) of antinodes of a surface standing wave generating between circular slots and λs is the wavelength of the surface wave, the radius difference Δrs between the plurality of concentric circles in nearly Δrs =n1 λs /2.

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 and a plasma processing method capable of generating stable plate-like plasma at high density, uniformity and low electron temperature in order to process large-area substrates at high speed and uniformly with high quality. And a method for manufacturing the element.

[0002]

2. Description of the Related Art Plasma processing apparatuses using microwaves as an excitation source for generating plasma include etching apparatuses, ashing apparatuses, cleaning apparatuses, CVD apparatuses, and the like.
A doping device, a surface modification device, and the like are known.

[0003] Etching of a substrate to be processed using a microwave plasma etching apparatus is performed, for example, as follows. That is, an etchant gas is introduced into a plasma processing chamber of a microwave plasma etching apparatus, and simultaneously, microwave energy is applied to excite and decompose the etchant gas, thereby etching the surface of a substrate to be processed disposed in the plasma processing chamber. .

An ashing process for a substrate to be processed using a microwave plasma ashing apparatus is performed, for example, as follows. That is, an ashing gas is introduced into a plasma processing chamber of a microwave plasma ashing apparatus, and simultaneously, microwave energy is supplied to excite and decompose the ashing gas, thereby ashing the surface of a substrate to be processed disposed in the plasma processing chamber. .

[0005] A film forming process of a substrate to be processed using a microwave plasma CVD apparatus is performed, for example, as follows. That is, a reactive gas is introduced into a plasma processing chamber of a microwave plasma CVD apparatus, and simultaneously, microwave energy is applied to excite and decompose the reactive gas, thereby forming a deposited film on a substrate to be processed disposed in the plasma processing chamber. Form.

The doping of a substrate to be processed using a microwave plasma doping apparatus is performed, for example, as follows. That is, a doping gas is introduced into a plasma processing chamber of a microwave plasma doping apparatus, and simultaneously, microwave energy is applied to excite and decompose a reaction gas, thereby doping the surface of a substrate to be processed disposed in the plasma processing chamber. Do.

In the plasma processing apparatus, since a microwave having a high frequency is used as a gas excitation source, the number of times of electron acceleration increases, so that the electron density increases, and gas molecules are efficiently ionized and excited. be able to. Therefore, the plasma processing apparatus has advantages in that gas ionization efficiency, excitation efficiency, and decomposition efficiency are high, and high-quality processing can be performed at high speed even at low temperature. In addition, since the microwave has a property of transmitting through the dielectric, the plasma processing apparatus can be configured as an electrodeless discharge type, and therefore, there is an advantage that a highly clean plasma processing can be performed.

In order to further increase the speed of such a plasma processing apparatus, a plasma processing apparatus using electron cyclotron resonance (ECR) has been put to practical use. ECR
When the magnetic flux density is 87.5 mT, the electron cyclotron frequency at which electrons rotate around the line of magnetic force matches the general microwave frequency of 2.45 GHz, and the electrons resonately absorb the microwaves and accelerate. This is a phenomenon in which high-density plasma is generated. In such an ECR plasma processing apparatus, the following four configurations are known as typical configurations of the microwave introduction unit and the magnetic field generation unit.

That is, (i) microwaves propagated through the waveguide are introduced into the cylindrical plasma generation chamber from the opposing surface of the substrate through the transmission window, and are coaxial with the central axis of the plasma generation chamber. (NTT type) in which the diverging magnetic field of the above is introduced through an electromagnetic coil provided around the plasma generation chamber;
i) The microwave transmitted through the waveguide is introduced into the bell-shaped plasma generation chamber from the opposite surface of the substrate to be processed, and a magnetic field coaxial with the center axis of the plasma generation chamber is provided around the plasma generation chamber. (Iii) a microwave is introduced into the plasma generation chamber from the periphery through a Risitano coil, which is a type of cylindrical slot antenna, and is connected to the center axis of the plasma generation chamber. A configuration in which a coaxial magnetic field is introduced through an electromagnetic coil provided around a plasma generation chamber (Rigitano method); (iv) A microwave transmitted through a waveguide is formed into a flat plate from an opposing surface of a substrate to be processed. A configuration in which a loop-shaped magnetic field parallel to the antenna plane is introduced through a permanent magnet provided on the back surface of the planar antenna (plane slot antenna). Tena method), it is.

In recent years, as an example of a plasma processing apparatus, an apparatus using an endless annular waveguide in which a plurality of linear slots are radially formed on a flat magnetic field surface as a uniform and efficient introduction apparatus for microwaves has been proposed. It has been proposed (JP-A-10-2
No. 33295). This plasma processing apparatus is shown in FIG.
FIG. 5A shows the plasma generation mechanism.
101 is a plasma processing chamber, 102 is a substrate to be processed, 103
Is a support for the base 102, 104 is a base temperature adjusting means for adjusting the temperature of the base 102, 105 is a high frequency bias applying means, 106 is a processing gas introducing means, 107 is an exhaust means, 108 is an exhaust conductance adjusting means, and 109 is an exhaust conductance adjusting means. A dielectric 110 that separates the plasma processing chamber 101 from the atmosphere;
Transmits microwave through the dielectric 109 to the plasma processing chamber 1
01 slotted endless annular waveguide for introduction into 01
11 is a microwave waveguide in the endless annular waveguide 110,
Reference numeral 112 denotes an E-branch that distributes the microwave introduced into the endless annular waveguide to the left and right, 113 denotes a standing wave generated by interference between the microwaves distributed by the E-branch 112, 114
Is a slot, 115 is a surface wave introduced through the slot 114 and propagated on the surface of the dielectric 109, 116 is a surface standing wave generated by interference between the surface waves 115 introduced from the adjacent slots 114, and 117 is a surface standing wave This is a surface wave interference plasma generated by electron excitation by waves.

The generation and processing of plasma are as follows.
Do it. Plasma processing chamber 10 via exhaust means 107
The inside of 1 is evacuated. Next, the plasma processing gas is processed.
Plasma processing at a predetermined flow rate through the
It is introduced into the science room 101. Next, the plasma processing chamber 101
Conductance adjustment provided between exhaust means 107
The means 108 is adjusted so that the inside of the plasma
Hold at pressure. If necessary, apply high frequency bias
Applying a bias to the substrate to be processed 102 through the step 105
You. Unterminated desired power from microwave power supply (not shown)
Provided in the plasma processing chamber 101 via the annular waveguide 110
Pay. At this time, it is introduced into the endless annular waveguide 110.
The microwaves are split right and left in the E-branch 112,
Propagation in waveguide 111 with longer guide wavelength than free space
I do. The distributed microwaves interfere with each other and generate
A standing wave 113 is generated for each half of the length. When the current is
Position, that is, an endless ring between two adjacent standing waves
Installed at the center of microwave waveguide 111 in waveguide 110
Through the dielectric 109 from the slot 114
The microwave introduced into the processing chamber 101 is in slot 1
Plasma is generated near 14. Electricity of generated plasma
The child density is n_ec= Ε₀m_eω^Two/ E^Two [Ε₀: Vacuum permittivity, m_e: Electronic mass, ω: Power supply angular frequency
Number, e: electron charge] (power supply frequency)
7 × 10 when the wave number is 2.45 GHz^Tencm ^-3) Beyond
Then, the microwave cannot propagate in the plasma,
Further, the electron density increases. At this time, the electron density is n_es= (1 + ε_d) Ε₀m_eω^Two/ E^Two [Ε_d: Relative dielectric constant of dielectric window]
Threshold density (quartz window [ε_d: 3.8] 3.4 ×
10¹¹cm^-3, AlN window [ε_d: 9.8], 7.6
× 10¹¹cm^-3), Δ = C / ω_p= C (ε₀m_e/ E^Twon_e)^1/2 = (2 / ωμ₀σ)^1/2 [C: speed of light, ω_p： Electron plasma angular frequency, μ₀： Vacuum transparent
Magnetic susceptibility, σ: plasma conductivity]
(For example, when the electron density is 1 × 10¹²cm^-3Over
Then, the skin thickness becomes 10 mm or less).
Is propagated as a surface wave 115. At this time,
Surface waves 115 introduced from the
Negotiate, λ_s= Λ_w｛1- (ε₀m_eω^Two/ E^Twon_e)^1/2｝ [Λ_w: Microwave wavelength in the dielectric window between complete conductors]
Surface standing wave 116 for each half of the wavelength of
Produces belly. This exuded into the plasma processing chamber 101
Electrons are accelerated by the surface standing wave 116 and the surface wave interference
Razuma (SIP: Surface-wave Interfered Plasma) 1
17 is generated. At this time, the processing gas introduction means 106
Process gas into the plasma processing chamber 101 through
The processing gas is excited by the generated high-density plasma.
The substrate to be processed 102 raised and placed on the support 103
Surface is treated.

By using such a plasma processing apparatus, the electron density is 2 × 10 ¹² with a uniformity of ± 3% or less within a large-diameter space having a diameter of 300 mm or more at a pressure of 1.33 Pa and a microwave power of 3 kW. cm ^-3 or more, less electron temperature 3 eV, since less dense low electron temperature plasma plasma potential 15V can be generated, the gas can be supplied to the substrate in a sufficiently active state by reacting, and the substrate surface by incident ions and charge-up It also reduces damage,
High quality and high speed processing becomes possible.

Further, 13 used in ashing processing or the like is used.
Under a high-pressure condition of about 3 Pa, high-density plasma having an electron density of about 5 × 10 ¹² cm ⁻³ is locally generated in the vicinity of the dielectric 109, so that high-speed and extremely low-damage processing can be performed.

[0014]

However, when processing is performed using a plasma processing apparatus that generates high-density low-electron temperature plasma as shown in FIG. 5, the electron density at the center is somewhat low, and depending on the processing, In some cases, the uniformity was reduced and the discharge became unstable.

A main object of the present invention is to solve the above-mentioned problems and to provide a plasma processing apparatus and a plasma processing method capable of stably generating a high-density low-electron temperature plasma having a high electron density at the center. .

[0016]

SUMMARY OF THE INVENTION The present inventor has solved the above-mentioned problems in the conventional plasma processing apparatus and has made intensive efforts to achieve the above object. As a result, the present inventors have developed means for supporting a substrate to be processed in a plasma processing chamber. A means for introducing a gas into the plasma processing chamber, a means for exhausting the plasma processing chamber, a plasma for introducing a microwave into the plasma processing chamber through a waveguide formed with a slot and a dielectric window. In the plasma processing apparatus having generation microwave introduction means, the slot is formed on a plurality of concentric circles having different radii on a plane parallel to the magnetic field surface of the microwave of the waveguide at a predetermined angular interval and a predetermined opening angle. a perforated with provided arcuate slot, n _l arcuate slot surface standing wave of the number of abdominal occurring between (odd), when the wavelength of the surface wave lambda _s, the Radius difference [Delta] r _s in the number of concentric circles was obtained substantially, the finding that it is possible to provide a plasma processing apparatus and plasma processing method which is a _{Δr s = n l λ s /} 2.

[0017]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIGS. 1 and 2 show an embodiment of the plasma processing apparatus of the present invention. FIG. 1A is an enlarged cross-sectional view of the entire device, FIG. 1B is an enlarged cross-sectional view of the vicinity of the slot, and FIG. 2 shows the arrangement of the slots.

Reference numeral 101 denotes a plasma processing chamber; 102, a substrate to be processed; 103, a support for the substrate 102;
2, a high-frequency bias applying means, 105 a processing gas introducing means, 107 an exhaust means, 108 an exhaust conductance adjusting means, 109 a dielectric material for separating the plasma processing chamber 101 from the atmosphere side, 110
Transmits microwave through the dielectric 109 to the plasma processing chamber 1
01 slotted endless annular waveguide for introduction into 01
Reference numeral 11 denotes an annular microwave waveguide in the endless annular waveguide 110, 112 denotes an E-branch for distributing the microwave introduced into the endless annular waveguide to the left and right, and 113 denotes a microwave distributed by the E-branch 112. Standing waves caused by interference between each other,
114 is a slot, 115 is a surface wave introduced through the slot 114 and propagated on the surface of the dielectric 109, 116 is a surface standing wave generated by interference between the surface waves 115 introduced from the adjacent slots 114, and 117 is a surface standing wave This is a surface wave interference plasma generated by electron excitation by a standing wave.

In the case of the TE ₁₀ (E ₀₁ ) mode, 120 is the E plane of the waveguide, and 121 is the H plane of the waveguide.

As shown in FIG. 2, the slots 114 are not radial as in the prior art, but are
Arc-shaped slots provided at predetermined angular intervals and predetermined opening angles on two concentric circles, and _ng represents a guide wavelength (in-path wavelength) λ of a circumference 1 _g of the annular waveguide (path). magnification for _g, n _l arcuate slot surface standing wave of the number of abdominal occurring between (odd), when the wavelength of the surface wave lambda _s, the difference between the radii of the two concentric circles substantially, [Delta] r _s = n _l λ _s / 2. The process of reaching this conclusion will be described with reference to FIG. Surface wave 1 generated from inner and outer slots 114
An odd number of surface standing waves 116 are generated between the inner and outer slots 114 at an interval of 波長 of the wavelength λ _s of the surface wave due to the interference between the 15. Therefore, in order most efficiently generate a surface standing wave, and out slot interval was concluded that should be _{Δr s = n l λ s /} 2. Also, since the cause interference efficiently, when the microwave intensity to be introduced from the inner and outer slots want the same extent, equidistant from the waveguide central radius represented by _{r c = n g λ g /} 2π Inside and outside slots should be formed. Therefore, in this case, the radius of the concentric circles in the presence of inner and outer slots must be _{r s = (n g λ g} / 2π) ± (n l λ s / 4).

When it is desired to reduce the surface wave intensity near the outer periphery of the window in order to suppress the leakage of microwaves and the occurrence of abnormal discharge near the outer periphery of the window, the incident wave and the reflected wave at the outer edge of the window may cause interference. We need to be strong. To this end, if n _w is an odd number, it is effective to set the distance d _sw between the outer slot and the window edge to d _sw = n _w λ _s / 4. Therefore, the radius r _w of the window in this case is expressed by _{r w = (n g λ g} / 2π) + {(n l + n w) λ s / 4}.

The generation and processing of the plasma are as follows.
Do it. Plasma processing chamber 10 via exhaust means 107
The inside of 1 is evacuated. Next, the plasma processing gas is processed.
Plasma processing at a predetermined flow rate through the
It is introduced into the science room 101. Next, the plasma processing chamber 101
Conductance adjustment provided between exhaust means 107
The means 108 is adjusted so that the inside of the plasma
Hold at pressure. If necessary, apply high frequency bias
Applying a bias to the substrate to be processed 102 through the step 105
You. Unterminated desired power from microwave power supply (not shown)
Provided in the plasma processing chamber 101 via the annular waveguide 110
Pay. At this time, it is introduced into the endless annular waveguide 110.
The microwaves are split right and left in the E-branch 112,
Propagation in waveguide 111 with longer guide wavelength than free space
I do. The distributed microwaves interfere with each other and generate
A standing wave 113 having a "belly" is generated every half of the length.
Arc-shaped stripes formed inside and outside the center of the "belly"
Plasma processing chamber from lot 114 through dielectric 109
Microwave introduced into 101 is near slot 114
To generate plasma. Electron density of generated plasma
Is n_ec= Ε₀m_eω^Two/ E^Two [Ε₀: Vacuum permittivity, m_e: Electronic mass, ω: Power supply angular frequency
Number, e: electron charge] (power supply frequency)
7 × 10 when the wave number is 2.45 GHz^Tencm ^-3) Beyond
Then, the microwave cannot propagate in the plasma,
Further, the electron density increases. At this time, the electron density is n_es= (1 + ε_d) Ε₀m_eω^Two/ E^Two [Ε_d: Relative dielectric constant of dielectric window]
Threshold density (quartz window [ε_d: 3.8] 3.4 ×
10¹¹cm^-3, AlN window [ε_d: 9.8], 7.6
× 10¹¹cm^-3), Δ = C / ω_p= C (ε₀m_e/ E^Twon_e)^1/2 = (2 / ωμ₀σ)^1/2 [C: speed of light, ω_p： Electron plasma angular frequency, μ₀： Vacuum transparent
Magnetic susceptibility, σ: plasma conductivity]
(For example, when the electron density is 1 × 10¹²cm^-3Over
Then, the skin thickness becomes 10 mm or less).
Is propagated as a surface wave 115. At this time,
Surface waves 115 introduced from the
Negotiate, λ_s= Λ_w｛1- (ε₀m_eω^Two/ E^Twon_e)^1/2｝ [Λ_w: Microwave wavelength in the dielectric window between complete conductors]
Surface standing wave 116 for each half of the wavelength of
Produces belly. This exuded into the plasma processing chamber 101
Electrons are accelerated by the surface standing wave 116 and the surface wave interference
Razuma (SIP: Surface-wave Interfered Plasma) 1
17 is generated.

At this time, when the processing gas is introduced into the plasma processing chamber 101 via the processing gas introducing means 106, the processing gas is excited by the generated high-density plasma and is placed on the support 103. The surface of the processed substrate 102 is processed.

It is preferable that the ratio of one circumference to the wavelength magnification in tube _ng be 2 to 5. Further, it is more effective to set the number n _l of antinodes of the surface standing wave between the arc-shaped slots to one of 1, 3, and 5. The angular interval of the arc-shaped slot is π / _ng
The relationship is more effective.

[0026] The opening angle of the arcuate slot, it is more effective to the [pi / 2n _g to 15π / 16n _g. Further, it is more effective if the opening angle of the arc-shaped slot is larger on the outside than on the inside.

The material of the endless annular waveguide 110 can be used as long as it is a conductor. However, in order to minimize the microwave propagation loss, Al, Cu, Ag /
SUS plated with Cu or the like is optimal.

The direction of the inlet of the endless annular waveguide 110 used in the present embodiment is such that the microwave can be efficiently introduced into the microwave waveguide 111 in the endless annular waveguide 110. The distribution may be two-way in the right and left direction inside the waveguide at the introduction part in the direction parallel to the interface and tangential to the propagation space or perpendicular to the magnetic field plane. Further, in order to improve the symmetry of the antenna, the antenna may be bifurcated at the center of the antenna and introduced into the endless annular waveguide 110 from two or more inlets.

Inner / outer slot 1 of endless annular waveguide 110
When it is desired to adjust the intensity of the microwave introduced from the slot 14, the opening angle of the slot may be changed, or the inner and outer slots may be shifted in the radial direction without changing the interval together.

The microwave frequency used is
It can be appropriately selected from the range of 0.8 GHz to 20 GHz.

The dielectric 109 used is SiO.
₂ based quartz and various _{glasses, Si 3 N 4, NaCl,} KC
1, LiF, CaF ₂ , BaF ₂ , Al ₂ O ₃ , AlN, M
Inorganic substances such as gO are suitable, but polyethylene, polyester, polycarbonate, cellulose acetate,
Films and sheets of organic materials such as polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyamide, and polyimide are also applicable.

In order to speed up the processing, a magnetic field generating means may be used. As a magnetic field to be used, a mirror magnetic field or the like can be applied. However, a magnetron magnetic field whose magnetic flux density near the slot 114 is larger than that of the magnetic field near the substrate 102 is optimal. As the magnetic field generating means, a permanent magnet other than a coil can be used.
When using a coil, other cooling means such as a water cooling mechanism or air cooling may be used to prevent overheating.

In order to improve the quality of the treatment, the surface of the substrate may be irradiated with ultraviolet light. As the light source, any light source that emits light absorbed by the substrate to be processed 102 or a gas attached to the substrate 102 can be used, and an excimer laser, an excimer lamp, a rare gas resonance line lamp, a low-pressure mercury lamp, and the like are suitable. .

The pressure in the plasma processing chamber 101 is 1.33.
× 10 ^-2 Pa or range of 1330 Pa, more preferably, if 1.33 × 10 ^-1 Pa to 13.3P of CVD
a, In the case of etching, from 6.65 × 10 ^-2 Pa to 6.6
5Pa, 13.3Pa to 1330P for ashing
It can be selected from the range of a.

An element is manufactured by performing the following processing. Formation of a deposited film using the plasma processing apparatus, Si ₃ by selecting the gas to be used suitably
N ₄ , SiO ₂ , Ta ₂ O ₅ , TiO ₂ , TiN, Al
Insulating film such as ₂ O ₃ , AlN, MgF ₂ , a-Si, poly
Semiconductor films such as Si, SiC, GaAs, Al, W,
Various deposited films such as metal films of Mo, Ti, Ta, etc. can be formed efficiently.

The substrate 102 to be processed may be a semiconductor, a conductive material, or an electrically insulating material.

As the conductive substrate, Fe, Ni, Cr,
Al, Mo, Au, Nb, Ta, V, Ti, Pt, Pb
And alloys thereof, such as brass and stainless steel.

Examples of the insulating substrate include SiO ₂ -based quartz and various glasses, Si ₃ N ₄ , NaCl, KCl, LiF, C
inorganic materials such as aF ₂ , BaF ₂ , Al ₂ O ₃ , AlN, and MgO, polyethylene, polyester, polycarbonate,
Cellulose acetate, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyamide,
Examples include films and sheets of organic substances such as polyimide.

As a gas used for forming a thin film on the substrate 102 by the CVD method, a generally known gas can be used.

Si such as a-Si, poly-Si, SiC, etc.
Gas introducing means 10 for forming a system-based semiconductor thin film
Si atoms introduced into the plasma processing chamber 101 through
The source gas contained is SiH_Four, Si_TwoH₆Such as
Inorganic silanes, tetraethylsilane (TES), tetra
Methylsilane (TMS), dimethylsilane (DMS),
Dimethyldifluorosilane (DMDFS), dimethyldi
Organosilanes such as chlorosilane (DMDCS), Si
F_Four, Si_TwoF₆, Si_ThreeF₈, SiHF_Three, SiH _TwoF_Two, S
iCl_Four, Si_TwoCl₆, SiHCl_Three, SiH_TwoCl_Two, S
iH_ThreeCl, SiCl_TwoF_TwoRoom temperature, such as halosilanes
Those which are in a gaseous state at normal pressure or which can be easily gasified
Is included. Also mixed with Si source gas in this case
As additive gas or carrier gas that may be introduced as
Is H_Two, He, Ne, Ar, Kr, Xe, and Rn.
Can be

The raw material containing Si atoms introduced through the processing gas introducing means 106 when forming a Si compound based thin film such as Si ₃ N ₄ or SiO ₂ is Si
Inorganic silanes such as H ₄ and Si ₂ H ₆ , tetraethoxysilane (TEOS), tetramethoxysilane (TMO)
S), octamethylcyclotetrasilane (OMCT
S), organic silanes such as dimethyldifluorosilane (DMDFS), dimethyldichlorosilane (DMDCS), SiF ₄ , Si ₂ F ₆ , Si ₃ F ₈ , SiHF ₃ , SiH
₂ F ₂ , SiCl ₄ , Si ₂ Cl ₆ , SiHCl ₃ , SiH ₂
Examples include halosilanes such as Cl ₂ , SiH ₃ Cl, and SiCl ₂ F ₂ , which are in a gaseous state at normal temperature and pressure or those which can be easily gasified. In this case, the nitrogen source gas or the oxygen source gas introduced at the same time is N ₂ ,
NH ₃ , N ₂ H ₄ , hexamethyldisilazane (HMD
S), O ₂ , O ₃ , H ₂ O, NO, N ₂ O, NO _{2 and the} like.

When a metal thin film of Al, W, Mo, Ti, Ta or the like is formed, as a raw material containing a metal atom to be introduced through the processing gas introducing means 106, trimethyl aluminum (TMAl), triethyl aluminum ( TEAl), triisobutylaluminum (TIBA)
l), dimethyl aluminum hydride (DMAl
H), organic metals such as tungsten carbonyl (W (CO) ₆ ), molybdenum carbonyl (Mo (CO) ₆ ), trimethylgallium (TMGa) and triethylgallium (TEGa), AlCl ₃ , WF ₆ , TiCl ₃ , and TaCl ₅ And the like. In this case, the additive gas or the carrier gas which may be mixed with the Si source gas and introduced is H ₂ , He, Ne, Ar, K
r, Xe, and Rn.

Al_TwoO_Three, AlN, Ta_TwoO_Five, TiO_Two,
TiN, WO_ThreeWhen forming metal compound thin films such as
Metal atoms introduced through the processing gas introduction means 106
As raw materials to be contained, trimethyl aluminum (TM
Al), triethyl aluminum (TEAl),
Sobutyl aluminum (TIBAl), dimethyl aluminum
Hydride (DMAlH), tungsten calc
Bonil (W (CO)₆), Molybdenum carbonyl (Mo (C
O)₆), Trimethylgallium (TMGa), triethyl
Organic metals such as gallium (TEGa), AlCl_Three,
WF₆, TiCl _Three, TaCl_FiveMetal halides, etc.
Is mentioned. In this case, the oxygen
The feed gas or the nitrogen source gas is O_Two, O_Three, H
_TwoO, NO, N_TwoO, NO_Two, N_Two, NH_Three, N_TwoH_Four, Heki
Samethyldisilazane (HMDS) and the like.

The etching gas introduced from the processing gas inlet 106 for etching the substrate surface includes F ₂ , CF ₄ , CH ₂ F ₂ , C ₂ F ₆ , C ₄ F ₈ , CF ₂ C
l ₂ , SF ₆ , NF ₃ , Cl ₂ , CCl ₄ , CH ₂ Cl ₂ , C ₂
Cl _{6 and the} like.

The ashing gas introduced from the processing gas inlet 106 for removing ashing such as photoresist from organic components on the surface of the substrate is O ₂ , O ₃ , H _2.
O, H ₂ , NO, N ₂ O, NO _{2 and the} like can be mentioned.

When the above-mentioned plasma processing apparatus is also applied to surface modification, by appropriately selecting a gas to be used, for example, Si, A
These substrates 102 are formed using l, Ti, Zn, Ta or the like.
Alternatively, oxidation treatment or nitridation treatment of the surface layer, and doping treatment of B, As, P or the like can be performed. Further, the plasma processing technique employed in the present invention can be applied to a cleaning method. In that case, it can be used for cleaning oxides, organic substances, heavy metals, and the like.

The oxidizing gas introduced through the processing gas inlet 106 when the substrate 102 is subjected to an oxidizing surface treatment includes O ₂ , O ₃ , H ₂ O, NO, N ₂ O, NO _{2 and the} like. Can be In addition, as the nitriding gas introduced through the processing gas inlet 106 when the substrate 102 is subjected to the nitriding surface treatment, N ₂ , NH ₃ , N ₂ H ₄ , hexamethyldisilazane (HMDS) and the like can be mentioned. .

The cleaning / ashing gas introduced from the processing gas inlet 106 for cleaning organic substances on the surface of the substrate 102 or for ashing removal of organic components such as photoresist on the surface of the substrate 102 is O ₂ , O ₃ , H ₂ O, H ₂ , NO, N ₂ O, NO _{2 and the} like can be mentioned. The cleaning gas introduced from the processing gas inlet 106 for cleaning the inorganic substance on the surface of the substrate 102 is F ₂ , CF ₄ , CH
₂ F ₂ , C ₂ F ₆ , C ₄ F ₈ , CF ₂ Cl ₂ , SF ₆ , NF _{3 and the} like.

[0049]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the plasma processing apparatus of the present invention will be described based on embodiments, but the present invention is not limited to these embodiments. Examples 1, 2, and 3 are examples of generating plasma, and Examples 5 to 11 are examples of processing using the plasma generated in Example 1, 2, or 3.

[0050] (Example 1) of the microwave plasma processing apparatus of the present invention, the waveguide peripheral length / guide wavelength ratio n _g is 4, the slot between the surfaces standing wave number n _l is 1, a dielectric quartz (epsilon _d :
An example in the case of 3.8) will be described. The slot arrangement is as shown in FIG. 3, but the basic configuration of the device is shown in FIG.
Is the same as that shown in FIG.

Reference numeral 101 denotes a plasma processing chamber; 102, a substrate to be processed; 103, a support for the substrate 102;
2, a means for adjusting the temperature, 105 a high frequency bias applying means, 106 a processing gas introducing means, 107 an exhaust means, 108 an exhaust conductance adjusting means, 109 a quartz window for separating the plasma processing chamber 101 from the atmosphere side, 110
In the plasma processing chamber 1, microwaves are passed through a quartz window 109.
01 is an endless annular waveguide, 111 is a microwave waveguide in the endless annular waveguide 110, 112 is an E-branch that distributes the microwave introduced into the endless annular waveguide to the left and right, Reference numeral 113 denotes a standing wave generated by interference between the microwaves distributed by the E-branch 112, and reference numeral 114 denotes a slot.

The generation and processing of plasma are performed as follows. Plasma processing chamber 10 via exhaust means 107
The inside of 1 is evacuated. Subsequently, a plasma processing gas is introduced into the plasma processing chamber 101 at a predetermined flow rate through the processing gas introduction unit 106. Next, the conductance adjusting means 108 provided between the plasma processing chamber 101 and the exhaust means 107 is adjusted to maintain the inside of the plasma processing chamber 101 at a predetermined pressure. If necessary, a bias is applied to the substrate to be processed 102 via the high frequency bias applying unit 105. A desired power is supplied from a microwave power supply (not shown) into the plasma processing chamber 101 through the endless annular waveguide 110. At this time, the microwave introduced into the endless annular waveguide 110 is split right and left by the E-branch 112 and propagates through the waveguide 111 with a longer guide wavelength than free space. The distributed microwaves interfere with each other and generate a standing wave 113 having eight “antinodes” for each half of the guide wavelength. Microwaves introduced into the plasma processing chamber 101 through the dielectric window 109 from the slots 114 provided inside and outside the center of the “belly” generate plasma near the slot 114. The electron plasma frequency of the generated plasma exceeds the power supply frequency (for example, when the electron density is 7
If the electron plasma frequency exceeds the power supply frequency of 2.45 GHz when the electron plasma frequency exceeds × 10 ¹⁰ cm ⁻³ , the microwave cannot propagate in the plasma (so-called cutoff),
The electron density further increases, and the skin thickness represented by δ = (2 / ωμ ₀ σ) ^1/2 [ω: power supply angular frequency, μ ₀ : vacuum permeability, σ: plasma conductivity] becomes sufficiently thin ( For example, when the electron density becomes 2 × 10 ¹² cm ⁻³ or more, the skin thickness becomes 20 μm.
mm or less), the surface of the quartz window
Propagate as The surface waves 115 introduced from the inner and outer slots 114 interfere with each other, and generate a surface standing wave 116 about every 28 mm. Electrons are accelerated by the surface standing wave 116 that has permeated into the plasma processing chamber 101, and the surface wave interference plasma (SIP: Surface-wave Interfered Plas) is generated.
ma) 117 is generated. At this time, if the processing gas is introduced into the plasma processing chamber 101 through the processing gas introducing means 106, the processing gas is excited by the generated high-density plasma, and the processing gas is placed on the support 103. The surface of the processing substrate 102 is processed.

For the quartz window 109, anhydrous synthetic quartz having a diameter of 368 mm and a thickness of 16 mm was used. Endless annular waveguide 1
In 10, the internal waveguide section has a cross-sectional dimension of 27 mm × 96 mm and a central diameter of 202.2 mm (the waveguide circumference is four times the guide wavelength). The material of the endless annular waveguide 110 is
In order to suppress the propagation loss of microwaves, all use Al. A slot 114 for introducing a microwave into the plasma processing chamber 101 is formed on a magnetic field surface of the endless annular waveguide 110. Here, the slot 114 is
Eight sets are formed on two concentric circles whose radii are approximately 87.3 mm and 115 mm, with an interval of 45 ° and an opening angle of 34 ° inside / 39 ° outside. The endless annular waveguide 110 has a 4E tuner, a directional coupler, an isolator, and 2.45 GHz.
Are connected in order.

Using a microwave plasma processing apparatus having a slot shown in FIG.
Plasma was generated under the conditions of m, pressure 1.33 Pa, and microwave power 3.0 kW, and the obtained plasma was measured. The plasma measurement was performed by the single probe method as follows. The voltage applied to the probe is -1
The current flowing through the probe was measured with an IV measuring instrument while changing the voltage from 0 to +30 V, and the electron density, electron temperature, and plasma potential were calculated from the obtained IV curve by the method of Langmuir et al. As a result, the electron density becomes 1.3
In the case of 3 Pa, 2.1 × 10 ¹² cm ⁻³ ± 2.7% (φ30
0 plane), and it was confirmed that a stable plasma having a high electron density was formed even in a low pressure region.

[0055] The plasma processing apparatus (Embodiment 2) The present invention, the waveguide peripheral length / guide wavelength ratio n _g is 3, the slot between the surface standing wave number n _l is 3, dielectric AlN (ε _d: 9 .8)
In the case of the above, an embodiment will be described. The configuration of the device is shown in FIG.
It is the same as FIG.

Reference numeral 101 denotes a plasma processing chamber; 102, a substrate to be processed; 103, a support for the substrate 102;
2, a high-frequency bias applying means, 106 a processing gas introducing means, 107 an exhaust means, 108 an exhaust conductance adjusting means, 109 an AlN window for separating the plasma processing chamber 101 from the atmosphere side, 11
Numeral 0 denotes an endless annular waveguide for introducing microwaves into the plasma processing chamber 101 through the AlN window 109, 111 denotes a microwave waveguide in the endless annular waveguide 110, 112
Is an E-branch that distributes the microwave introduced into the endless annular waveguide to the left and right, 113 is a standing wave generated by interference between the microwaves distributed by the E-branch 112, and 114 is a slot.

The generation and processing of the plasma are performed as follows. Plasma processing chamber 10 via exhaust means 107
The inside of 1 is evacuated. Subsequently, a plasma processing gas is introduced into the plasma processing chamber 101 at a predetermined flow rate through the processing gas introduction unit 106. Next, the conductance adjusting means 108 provided between the plasma processing chamber 101 and the exhaust means 107 is adjusted to maintain the inside of the plasma processing chamber 101 at a predetermined pressure. If necessary, a bias is applied to the substrate to be processed 102 via the high frequency bias applying unit 105. A desired power is supplied from a microwave power supply (not shown) into the plasma processing chamber 101 through the endless annular waveguide 110. At this time, the microwave introduced into the endless annular waveguide 110 is split right and left by the E-branch 112 and propagates through the waveguide 111 with a longer guide wavelength than free space. The distributed microwaves interfere with each other to generate a standing wave 113 having six “antinodes” for every half of the guide wavelength. Microwaves introduced into the plasma processing chamber 101 through the dielectric window 109 from the slots 114 provided inside and outside the center of the “belly” generate plasma near the slot 114. The electron plasma frequency of the generated plasma exceeds the power supply frequency (for example, when the electron density is 7
If the electron plasma frequency exceeds the power supply frequency of 2.45 GHz when the electron plasma frequency exceeds × 10 ¹⁰ cm ⁻³ , the microwave cannot propagate in the plasma (so-called cutoff),
The electron density further increases, and the skin thickness represented by δ = (2 / ωμ ₀ σ) ^1/2 [ω: power supply angular frequency, μ ₀ : vacuum permeability, σ: plasma conductivity] becomes sufficiently thin ( For example, when the electron density becomes 2 × 10 ¹² cm ⁻³ or more, the skin thickness becomes 20 μm.
mm or less), the surface of the AlN window
Propagate as 5. The surface waves 115 introduced from the inner and outer slots 114 interfere with each other, and generate a surface standing wave 116 about every 17 mm. Electrons are accelerated by the surface standing wave 116 that has permeated into the plasma processing chamber 101 and the surface-wave interference plasma (SIP: Surface-wave Interfered Pl).
asma) 117 is generated. At this time, if the processing gas is introduced into the plasma processing chamber 101 through the processing gas introducing means 106, the processing gas is excited by the generated high-density plasma, and the processing gas is placed on the support 103. The surface of the processing substrate 102 is processed.

As the AlN window 109, a normal-pressure sintered high-purity AlN window with a diameter of 322 mm and a thickness of 10 mm containing yttria was used. The endless annular waveguide 110 has a cross section of 27 mm × 96 mm in inner waveguide section and a center diameter of 151.96 mm.
6 mm (the waveguide circumference is three times the guide wavelength). The material of the endless annular waveguide 110 is all Al in order to suppress the propagation loss of the microwave. The microwave is applied to the magnetic field surface of the endless annular waveguide 110 by the plasma processing chamber 10.
A slot 114 is formed for introduction into the slot 1.
Here, the slot 114 has a radius of approximately 50.3 mm and 1
Six pairs are formed on two concentric circles of 01 mm at an interval of 60 ° and an opening angle of 45 ° inside / 53 ° outside. To the endless annular waveguide 110, a 4E tuner, a directional coupler, an isolator, and a microwave power supply (not shown) having a frequency of 2.45 GHz are sequentially connected.

Using the plasma processing apparatus shown in FIG. 3, an Ar flow rate of 500 sccm and a pressure of 13.3 × 10 ^-1 P
a, Plasma was generated under the condition of microwave power of 3.0 kW, and the obtained plasma was measured. The plasma measurement was performed by the single probe method as follows. The voltage applied to the probe was changed in the range of -10 to +30 V, the current flowing through the probe was measured by an IV measuring instrument, and the obtained IV curve was used to determine the electron density, the electron temperature, and the plasma by the method of Langmuir et al. The potential was calculated. As a result, the electron density is 2.8 × 10 ¹² / cm ³ ± 4.3% (within φ300 plane) in the case of 13.3 × 10 ^-1 Pa, and a stable plasma having a high electron density is obtained even in a low pressure region. It was confirmed that it was formed.

[0060] The plasma processing apparatus (Embodiment 3) The present invention, the waveguide peripheral length / guide wavelength ratio n _g is 5, the slot between the surfaces standing wave number n _l is 3, dielectric AlN (ε _d: 9 .8)
An example of the device in the case of the above will be described. Although the arrangement of the slots is as shown in FIG. 4, the basic configuration of the device is the same as that shown in FIG.

Reference numeral 101 denotes a plasma processing chamber; 102, a substrate to be processed; 103, a support for the substrate 102;
2, a means for adjusting the temperature, 105 a high frequency bias applying means, 106 a processing gas introducing means, 107 an exhaust means, 108 an exhaust conductance adjusting means, 109 a quartz window for separating the plasma processing chamber 101 from the atmosphere side, 110
In the plasma processing chamber 1, microwaves are passed through a quartz window 109.
01 is an endless annular waveguide, 111 is a microwave waveguide in the endless annular waveguide 110, 112 is an E-branch that distributes the microwave introduced into the endless annular waveguide to the left and right, Reference numeral 113 denotes a standing wave generated by interference between the microwaves distributed by the E-branch 112, and reference numeral 114 denotes a slot.

The generation and processing of plasma are performed as follows. Plasma processing chamber 10 via exhaust means 107
The inside of 1 is evacuated. Subsequently, a plasma processing gas is introduced into the plasma processing chamber 101 at a predetermined flow rate through the processing gas introduction unit 106. Next, the conductance adjusting means 108 provided between the plasma processing chamber 101 and the exhaust means 107 is adjusted to maintain the inside of the plasma processing chamber 101 at a predetermined pressure. If necessary, a bias is applied to the substrate to be processed 102 via the high frequency bias applying unit 105. A desired power is supplied from a microwave power supply (not shown) into the plasma processing chamber 101 through the endless annular waveguide 110. At this time, the microwave introduced into the endless annular waveguide 110 is split right and left by the E-branch 112 and propagates through the waveguide 111 with a longer guide wavelength than free space. The distributed microwaves interfere with each other to generate a standing wave 113 having ten “antinodes” for every half of the guide wavelength. Microwaves introduced into the plasma processing chamber 101 through the dielectric window 109 from the slots 114 provided inside and outside the center of the “belly” generate plasma near the slot 114. When the electron plasma frequency of the generated plasma exceeds the power supply frequency (for example, when the electron density exceeds 7 × 10 ¹⁰ cm ⁻³ , the electron plasma frequency exceeds the power supply frequency of 2.45 GHz), the microwave propagates in the plasma. It becomes impossible (so-called cut-off), and the electron density further increases. Δ = (2 / ωμ ₀ σ) ^1/2 [ω: power supply angular frequency, μ ₀ : vacuum magnetic permeability, σ: plasma conductivity] The skin thickness becomes sufficiently thin (for example, when the electron density becomes 2 × 10 ¹² cm ⁻³ or more, the skin thickness becomes 20
mm or less), the surface of the AlN window
Propagate as 5. The surface waves 115 introduced from the inner and outer slots 114 interfere with each other, and generate a surface standing wave 116 about every 17 mm. Electrons are accelerated by the surface standing wave 116 that has permeated into the plasma processing chamber 101 and the surface-wave interference plasma (SIP: Surface-wave Interfered Pl).
asma) 117 is generated. At this time, if the processing gas is introduced into the plasma processing chamber 101 through the processing gas introducing means 106, the processing gas is excited by the generated high-density plasma, and the processing gas is placed on the support 103. The surface of the processing substrate 102 is processed.

For the AlN window 109, a normal-pressure sintered high-purity AlN having a diameter of 354 mm and a thickness of 10 mm containing an yttria auxiliary was used. The endless annular waveguide 110 has a cross-sectional size of the internal waveguide of 27 mm × 96 mm and a center diameter of 252.96 mm.
7 mm (the waveguide circumference is five times the guide wavelength). The material of the endless annular waveguide 110 is all Al in order to suppress the propagation loss of the microwave. The microwave is applied to the magnetic field surface of the endless annular waveguide 110 by the plasma processing chamber 10.
A slot 114 is formed for introduction into the slot 1.
Here, the slot 114 has a radius of approximately 101 mm and 15 mm.
Eight pairs are formed on two concentric circles of 2 mm at intervals of 36 ° and an opening angle of 32 ° inside / 27 ° outside. To the endless annular waveguide 110, a 4E tuner, a directional coupler, an isolator, and a microwave power supply (not shown) having a frequency of 2.45 GHz are sequentially connected.

Using a microwave plasma processing apparatus having a slot shown in FIG. 4, an Ar flow rate of 500 sccm was used.
Plasma was generated under the conditions of a pressure of 1.33 Pa and a microwave power of 3.0 kW, and the obtained plasma was measured. The plasma measurement was performed by the single probe method as follows. The voltage applied to the probe was changed in the range of -10 to +30 V, the current flowing through the probe was measured by an IV measuring instrument, and the obtained IV curve was used to determine the electron density, the electron temperature, and the plasma by the method of Langmuir et al. The potential was calculated. As a result, the electron density is 1.33P
In the case of a, it was 2.1 × 10 ¹² cm ⁻³ ± 2.3% (within φ300 plane), and it was confirmed that a stable plasma having a high electron density was formed even in a low pressure region.

Example 4 The photoresist was ashed using the slots shown in FIG. 3 and the microwave plasma processing apparatus shown in FIG.

As the substrate 102, silicon (S) immediately after the interlayer SiO ₂ film was etched and via holes were formed.
i) A substrate (φ8 inch) was used. First, the Si substrate 1
02 on the substrate support 103 and the temperature control means 10
After heating the Si substrate 102 to 250 ° C. through the vacuum pump 4, the inside of the plasma processing chamber 101 was evacuated to a vacuum of 1.33 × 10 ⁻³ Pa through the exhaust system 107. Oxygen gas is supplied at 500 scc through the plasma processing gas inlet 106.
It was introduced into the plasma processing chamber 101 at a flow rate of m. Next, the conductance valve 108 provided between the plasma processing chamber 101 and the exhaust system 107 is adjusted to
01 was kept at 3.99 Pa. Plasma processing chamber 10
1.5k from 2.45GHz microwave power supply within 1.
W power was supplied through the endless annular waveguide 110.
Thus, plasma was generated in the plasma processing chamber 101. At this time, the oxygen gas introduced through the plasma processing gas inlet 106 is excited, decomposed, and reacted in the plasma processing chamber 101 to become oxygen radicals, and the Si substrate 10
The photoresist was transported in the direction 2 and oxidized the photoresist on the Si substrate 102, and was vaporized and removed. After the ashing, the ashing speed and the substrate surface charge density were evaluated.

The ashing rate and uniformity obtained are:
The value was extremely good at 5.8 μm / min ± 4.7%, and the surface charge density was a sufficiently low value of −1.5 × 10 ¹¹ cm ⁻² .

(Embodiment 5) The slot shown in FIG.
Ashing of the photoresist was performed using the microwave plasma processing apparatus shown in FIG.

As the substrate 102, silicon (S) immediately after the interlayer SiO ₂ film was etched and via holes were formed
i) A substrate (φ8 inch) was used. First, the Si substrate 1
02 is placed on the substrate support 103, and the inside of the plasma processing chamber 101 is evacuated via an exhaust system (not shown).
The pressure was reduced to 1.33 × 10 ⁻³ Pa. Oxygen gas was introduced into the plasma processing chamber 101 through the plasma processing gas inlet 106 at a flow rate of 1 slm. Next, the conductance valve 108 provided between the plasma processing chamber 101 and the exhaust system 107 is adjusted, and the inside of the processing chamber 101 is
It was kept at 9.8 Pa. In the plasma processing chamber 101,
1.5 kW of power was supplied from a microwave power source of 2.45 GHz via the unterminated annular waveguide 103. Thus, plasma was generated in the plasma processing chamber 101.
At this time, the oxygen gas introduced via the plasma processing gas inlet 106 is excited, decomposed, and reacted in the plasma processing chamber 101 to become oxygen radicals, transported in the direction of the Si substrate 102, and The resist was oxidized, vaporized and removed. After the ashing, the ashing speed and the substrate surface charge density were evaluated.

The ashing rate and uniformity obtained are:
It was extremely large at 5.3 μm / min ± 4.4%, and the surface charge density was a sufficiently low value of −1.7 × 10 ¹¹ cm ⁻² .

Example 6 Using the microwave plasma processing apparatus shown in FIGS. 1 and 2, a silicon nitride film for protecting a semiconductor element was formed.

As the base 112, a P-type single-crystal silicon substrate with an interlayer SiO ₂ film on which an Al wiring pattern (line and space 0.5 μm) was formed (plane orientation <10
0>, resistivity 10 Ωcm). First, after the silicon substrate 102 is set on the base support 103, the inside of the plasma processing chamber 101 is evacuated via the exhaust system 107,
The pressure was reduced to a value of 1.33 × 10 ⁻⁵ Pa. Subsequently, a heater (not shown) is energized, and the silicon substrate 102 is heated to 300 ° C.
And the substrate was kept at this temperature. 600 sccm of nitrogen gas through the plasma processing gas inlet 106
And a monosilane gas was introduced into the processing chamber 101 at a flow rate of 200 sccm. Next, the conductance valve 108 provided between the plasma processing chamber 101 and the exhaust system 107 is adjusted to make the inside of the processing chamber 101 2.66.
It was kept at Pa. Next, power of 3.0 kW was supplied from a microwave power supply (not shown) of 2.45 GHz via the endless annular waveguide 103. Thus, plasma was generated in the plasma processing chamber 101. At this time, the nitrogen gas introduced through the plasma processing gas inlet 106 is excited and decomposed into active species in the plasma processing chamber 101, is transported in the direction of the silicon substrate 102, reacts with the monosilane gas, and reacts with the silicon nitride. A film was formed on the silicon substrate 102 with a thickness of 1.0 μm. After the film formation, film quality such as film formation speed and stress was evaluated. The stress was determined by measuring the change in the amount of warpage of the substrate before and after film formation using a laser interferometer Zygo (trade name).

The film formation rate and uniformity of the obtained silicon nitride film were extremely large at 520 nm / min ± 3.2%, the film quality was 1.2 × 10 ⁹ dyne / cm ² (compression), and the leak current was 1 It was confirmed that the film was a very good film having a thickness of 0.3 × 10 ⁻¹⁰ A / cm ² and a withstand voltage of 9 MV / cm.

(Embodiment 7) The slot shown in FIG.
A silicon oxide film and a silicon nitride film for preventing plastic lens reflection were formed using the microwave plasma processing apparatus shown in FIG.

As the substrate 102, a plastic convex lens having a diameter of 50 mm was used. After the lens 102 was set on the substrate support 103, the inside of the plasma processing chamber 101 was evacuated through the exhaust system 107 to reduce the pressure to 1.33 × 10 ⁻⁵ Pa. Nitrogen gas was introduced into the processing chamber 101 at a flow rate of 160 sccm, and monosilane gas was introduced at a flow rate of 100 sccm via the plasma processing gas inlet 115. Next, the plasma processing chamber 101 and the exhaust system 10
7, the conductance valve 108 was adjusted to maintain the inside of the processing chamber 101 at 9.31 × 10 ⁻¹ Pa. Next, power of 3.0 kW was supplied from a 2.45 GHz microwave power supply (not shown) into the plasma processing chamber 101 through the endless annular waveguide 103. Thus,
Plasma was generated in the plasma processing chamber 101. At this time, the nitrogen gas introduced through the plasma processing gas inlet 106 is excited and decomposed in the plasma processing chamber 101 to become active species such as nitrogen atoms, is transported in the direction of the lens 102, and reacts with the monosilane gas. Then, a silicon nitride film was formed on the lens 102 with a thickness of 21 nm.

Next, oxygen gas and monosilane gas were introduced into the processing chamber 101 through the plasma processing gas inlet 106 at a flow rate of 200 sccm and monosilane gas at a flow rate of 100 sccm. Next, the plasma processing chamber 101 and the exhaust system 10
7, the conductance valve 108 was adjusted to maintain the inside of the processing chamber 101 at 1.33 × 10 ⁻¹ Pa. Then, 2.0 kW of power was supplied from a 2.45 GHz microwave power supply (not shown) into the plasma generation chamber 101 via the endless annular waveguide 103. Thus,
Plasma was generated in the plasma processing chamber 101. At this time, the oxygen gas introduced through the plasma processing gas introduction port 106 is excited and decomposed in the plasma processing chamber 101 to become active species such as oxygen atoms, is transported in the direction of the glass substrate 102, and is reacted with the monosilane gas. As a result of the reaction, a silicon oxide film was formed on the glass substrate 102 with a thickness of 86 nm. After the film formation, the film formation speed and the reflection characteristics were evaluated.

The film formation rate and uniformity of the obtained silicon nitride film and silicon oxide film were 330 nm / min, respectively.
± 2.4%, good at 350 nm / min ± 2.6, and the film quality was confirmed to be a very good optical characteristic with a reflectivity at around 500 nm of 0.2%.

(Embodiment 8) The slot shown in FIG.
The silicon oxide film for interlayer insulation of the semiconductor element was formed using the microwave plasma processing apparatus shown in FIG.

As the substrate 102, a P-type substrate having an Al pattern (line and space 0.5 μm) formed on the uppermost portion was used.
Type single crystal silicon substrate (plane orientation <100>, resistivity 10
Ωcm). First, the silicon substrate 102 was set on the base support 103. The inside of the plasma processing chamber 101 is evacuated via the exhaust system 107 to 1.33 × 10 ⁻⁵ P
The pressure was reduced to the value of a. Subsequently, the heater 104 is energized,
The silicon substrate 102 was heated to 300 ° C., and the substrate was kept at this temperature. Oxygen gas was introduced into the processing chamber 101 at a flow rate of 500 sccm and monosilane gas at a flow rate of 200 sccm through the plasma processing gas inlet 106. Next, the plasma processing chamber 101 and the exhaust system 107
The conductance valve 108 provided between was adjusted to keep the inside of the plasma processing chamber 101 at 3.99 Pa. Next, 13.56 MHz high frequency application means 105
Of 300 W to the substrate support 102 through a microwave power source of 2.45 GHz and 2.0 W
kW of power was supplied into the plasma processing chamber 101 via the endless annular waveguide 110. Thus, plasma was generated in the plasma processing chamber 101. The oxygen gas introduced through the plasma processing gas inlet 106 is excited and decomposed into active species in the plasma processing chamber 101, is transported in the direction of the silicon substrate 102, reacts with the monosilane gas, and converts the silicon oxide film into silicon. 0.8μ on the substrate 102
m. At this time, the ion species is accelerated by the RF bias and is incident on the substrate 102 to cut the film on the pattern and improve the flatness. After the treatment, the film forming speed, uniformity, dielectric strength, and step coverage were evaluated. The step coverage was evaluated by observing a cross section of the silicon oxide film formed on the Al wiring pattern with a scanning electron microscope (SEM) and observing voids.

The obtained silicon oxide film has a good film forming rate and uniformity of 250 nm / min ± 2.7%, a film quality of 8.5 MV / cm, a void-free film and a good film quality. Was confirmed.

(Embodiment 9) The slot shown in FIG.
Was used to etch the inter-layer SiO ₂ film between semiconductor elements.

As the substrate 102, a 1 μm thick interlayer S was formed on an Al pattern (line and space 0.18 μm).
A P-type single crystal silicon substrate (plane orientation <100>, resistivity 10 Ωcm) on which an iO ₂ film was formed was used. First, after placing the silicon substrate 102 on the base support 103,
The inside of the plasma processing chamber 101 was evacuated through the exhaust system 107 to reduce the pressure to 1.33 × 10 ⁻⁵ Pa. 100 s of C ₄ F ₈ via the gas inlet 106 for plasma processing
It was introduced into the plasma processing chamber 101 at a flow rate of ccm. Next, the conductance valve 108 provided between the plasma processing chamber 101 and the exhaust system 107 was adjusted to maintain the inside of the plasma processing chamber 101 at a pressure of 1.33 Pa. Next, 30.56 MHz is applied through 13.56 MHz high frequency application means.
While applying 0 W power to the substrate support 102,
A power of 2.0 kW from a microwave power supply of 2.45 GHz is supplied to the plasma processing chamber 10 through the endless annular waveguide 110.
1. Thus, plasma was generated in the plasma processing chamber 101. Gas inlet for plasma processing 10
C ₄ F ₈ gas introduced through the plasma processing chamber 10
Excited and decomposed into active species in the silicon substrate 1
02, and the interlayer SiO ₂ film was etched by the ions accelerated by the self-bias.
The cooler 104 increased the substrate temperature only up to 80 ° C. After the etching, the etching rate, the selectivity, and the etching shape were evaluated. Etching shape is
The cross section of the etched silicon oxide film was observed and evaluated with a scanning electron microscope (SEM).

The etching rate and uniformity and the selectivity ratio to PR were as good as 540 nm / min ± 4.2%, 16, and it was confirmed that the etching shape was almost vertical and the microloading effect was small.

(Embodiment 10) Using the slots shown in FIG. 3 and the microwave plasma processing apparatus shown in FIG. 1, the polyaryl ether (PAE) film for semiconductor device interlayer insulation was etched.

As the substrate 102, a 0.6 μm thick PA
0.18 μm SiO as hard mask on E film_TwoMembrane
P-type single crystal silicon base with 0.3μm thick turn
Using a plate (plane orientation <100>, resistivity 10Ωcm)
Was. First, the silicon substrate 102 is placed on the base support 103.
Install and cool substrate temperature to -10 ° C by cooler 104
After that, the inside of the plasma processing chamber 101 via the exhaust system 107
Is evacuated to 1.33 × 10^-FiveReduce the pressure to the value of Pa
Was. N through the plasma processing gas inlet 106 _Two2
Introduced into the plasma processing chamber 101 at a flow rate of 00 sccm.
Was. Next, the plasma processing chamber 101 and the exhaust system 107
Adjust the conductance valve 108 provided between them,
The inside of the plasma processing chamber 101 was maintained at a pressure of 1.33 Pa.
Was. Then, through the 1 MHz high frequency applying means 105
When 300 W of power is applied to the substrate support 102,
2.0 kW from 2.45 GHz microwave power supply
Power is supplied to the plasma processing chamber through the endless annular waveguide 110.
101. Thus, the plasma processing chamber 101
A plasma was generated inside. Gas inlet for plasma processing
N introduced via 106_TwoGas is plasma processing chamber 1
Excited and decomposed into active species in silicon substrate 01
Transported in the direction of 102 and accelerated by self-bias
The PAE film was etched by the ions. Edge
After etching, etching rate, selectivity, and etching type
The condition was evaluated. Etched shape is etched
Scanning electron microscope (SE)
M) was observed and evaluated.

The etching rate and uniformity, and the selectivity to SiO ₂ were as good as 660 nm / min ± 3.7% and 10;
It was confirmed that the etching shape was almost vertical and the microloading effect was small.

[0087]

As described above, according to the present invention,
A high-density low-electron temperature plasma having a high electron density at the center can be generated stably, and high-quality processing can be performed at high speed, uniformly, and stably.

[Brief description of the drawings]

FIG. 1 is a schematic view of an embodiment of a plasma processing apparatus according to the present invention.

FIG. 2 is a standing wave 3 using an AlN window according to an embodiment of the present invention.
It is a schematic diagram of the slot of the plasma processing apparatus using the individually excited 3λgPMA antenna.

FIG. 3 is a schematic view of a slot of a plasma processing apparatus using a 4λg PMA antenna excited with one standing wave using a quartz window according to an embodiment of the present invention.

FIG. 4 is a standing wave 3 using an AlN window according to an embodiment of the present invention.
It is a schematic diagram of the slot of the plasma processing apparatus using the individually excited 5λgPMA antenna.

FIG. 5 is a schematic view of a conventional plasma processing apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 101 Plasma processing chamber 102 Substrate to be processed 103 Substrate support 104 Substrate temperature adjusting means 105 High frequency bias applying means 106 Processing gas introducing means 107 Exhaust means 108 Conductance adjusting means 109 Dielectric 110 Non-terminal annular waveguide 111 Microwave annular conductor Waveguide 112 Microwave introduction E-branch 113 Standing wave in waveguide 114 Slot 115 Surface wave 116 Surface standing wave 117 Surface wave interference plasma 120 E-plane of waveguide 121 H-plane of waveguide

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) H01L 21/3065 H05H 1/46 B H05H 1/46 H01L 21/302 B F term (Reference) 4G075 AA24 AA30 BC04 BC06 BC07 CA12 CA26 DA01 EB44 FA01 FB04 FC15 4K030 AA06 AA18 BA40 BA44 CA04 CA06 CA07 FA01 JA03 KA30 LA15 4K057 DA16 DB01 DB02 DB03 DB04 DB05 DB06 DB08 DD01 DE01 DE02 DE06 DE07 DE08 DE09 DM02 DM29 DM37 DM38 DN01 5F004 AA01 BA20 CA14 DA01 DA02 DA15 DA17 DA18 DA24 DA26 DA27 DB03 DB26 5F045 AA09 AB03 AB32 AB33 AC01 AC11 AC15 AD07 AE17 BB02 DP04 DQ10 EB02 EH03 EH20 GB08

Claims (16)

[Claims] 1. A means for supporting a substrate to be processed in a plasma processing chamber, a means for introducing a gas into the plasma processing chamber, a means for exhausting the plasma processing chamber, a waveguide having a slot formed therein, and a dielectric. A plasma generation microwave introducing means for introducing microwaves into the plasma processing chamber through a window, wherein the slot has a radius of a plane parallel to a magnetic field plane of the microwave of the waveguide. Λ is an arc-shaped slot provided on a plurality of different concentric circles at predetermined angular intervals and a predetermined opening angle, and n _l is the number of antinodes (odd number) of surface standing waves generated between the arc-shaped slots, λ _Assuming that _s is the wavelength of the surface wave, a difference Δr _s between the radii of the plurality of concentric circles is approximately Δr _s = n _l λ _s / 2. 2. The plasma processing apparatus according to claim 1, wherein the number of said concentric circles is two. Radius r _s of the claim 3, wherein said two concentric circles, n _g a ratio to road within the wavelength lambda _g of the annular waveguide round length l _g, n _l an arcuate slot between the resulting surface of the standing wave antinodes number (odd number), substantially when the wavelength of the surface wave _{λ s, r s = (n} g λ g / 2π) plasma according to claim 2, characterized in that the _{± (n l λ s / 4} ) Processing equipment. 4. The radius r _w of the dielectric window is approximately r _w = ( _ng λ _g / 2π) + {(n _l + n _w ) λ _s / 4} where n _w is an odd number. The plasma processing apparatus according to claim 2, wherein: 5. The value of the circumference length / in-path wavelength magnification _ng is:
The plasma processing apparatus according to any one of claims 2 to 4, wherein the number is 2 to 5. 6. The plasma according to claim 2, wherein the number n _l of antinodes of the surface standing wave between the arc-shaped slots is one of 1, 3, and 5. Processing equipment. 7. An angular interval between the arc-shaped slots is π /
The plasma processing apparatus according to any one of claims 2 to 5, wherein the value is _ng . 8. An opening angle of the arc-shaped slot is π / 2.
The plasma processing apparatus according to claim 7, wherein n _g is in a range of _ng to 15π / 16 ng. 9. The arc-shaped slot according to claim 2, wherein an opening angle of the arc-shaped slot is larger on the outside than on the inside.
The plasma processing apparatus according to any one of the above. 10. The plasma processing apparatus according to claim 2, wherein a main component of the dielectric window is aluminum nitride. 11. The plasma processing apparatus according to claim 2, further comprising means for applying a high-frequency bias to a means for supporting the substrate to be processed. 12. A plasma processing method for processing a substrate to be processed by placing a substrate to be processed in a plasma processing chamber and introducing microwaves into the plasma processing chamber through a dielectric window into the plasma processing chamber. As means for introducing microwaves into the processing chamber, there is provided an annular waveguide having an arc-shaped slot formed by drilling at a predetermined angular interval and a predetermined opening angle on two concentric circles having different radii on the magnetic field surface of the microwave. If n _l is the number of antinodes (odd number) of surface standing waves generated between the arc-shaped slots and λ _s is the wavelength of the surface wave, the difference between the radii of the two concentric circles is approximately: Δr _s = n _l providing a microwave introducing means is a lambda _s / 2, the steps of placing the target substrate in the plasma processing chamber, comprising the steps of evacuating the plasma processing chamber, to the plasma processing chamber And introducing a microwave into the plasma processing chamber using the annular waveguide to generate plasma, and processing the substrate. Plasma processing method. 13. The plasma processing method according to claim 12, wherein the processing in the step of processing the substrate is at least one of etching, ashing, and cleaning. 14. The plasma processing method according to claim 12, wherein the processing in the step of processing the substrate is at least one of CVD, surface modification, and doping. 15. A method for manufacturing an element, comprising a step of treating the surface of a substrate on which the element is formed by the plasma processing method according to claim 12. 16. The method according to claim 15, wherein the plasma processing is ashing of a resist on a surface of the substrate.