JPH02211619A - Formation of functional deposited film by micro wave plasma cvd method - Google Patents

Abstract

PURPOSE:To enable stable mass-production of a functional deposited film of good reproducibility by providing a film formation space in connection with a plasma production chamber and by injecting micro wave energy into this film formation space. CONSTITUTION:Micro wave is introduced from a rectangular waveguide tube 201 into a plasma production chamber 203. Hydrogen gas, etc., introduced from a gas introduction port 210 is plasma-processed by electric field energy of micro wave and hydrogen atom in an excited state is produced. The produced hydrogen atom in the excited state is introduced through a metal mesh 209 into a film formation chamber 204, and collides with raw gas which is supplied from a gas introduction tube 205, thereby producing chemical reaction and forming a deposited film onto a substrate 207.

Description

[Detailed description of the invention] [Technical field to which the invention pertains] The present invention relates to a functional film, particularly a semiconductor device, a photovoltaic element, a thin film semiconductor element, a line sensor for image input,
The present invention relates to a method for forming a semiconductor deposited film useful for applications such as imaging devices and electrophotographic photosensitive devices.

[Description of prior art]

Regarding the formation of semiconductor thin films used in semiconductor devices, photovoltaic elements, line sensors for image input, imaging devices, electrophotographic photosensitive devices, etc., the desired electrical properties, physical properties, type of application, etc. Appropriate film formation methods are adopted in view of various points. As such film forming methods, plasma CVD method, reactive sputtering method,
Ion blating method, photo CVD method, thermal CVD method, M
OCVD method, MBE method, etc. are known. Among these film-forming methods, the plasma CVD method has been evaluated as the most effective and has been widely adopted. However, the plasma CVD method has several problems that need to be solved. In other words, the reaction process for forming a deposited film by the plasma CVD method is considerably more complicated than that of the so-called CVD method, and the reaction mechanism is still unclear in many ways.Also, the parameters for forming the deposited film are many (e.g., substrate temperature, flow rates and ratios of introduced gases, pressure during formation,
(high-frequency power, electrode structure, reaction vessel structure, pumping speed, plasma generation method, etc.). Because these parameters need to be set in an organic relationship, the plasma may become unstable and the deposited film may deteriorate. May cast a significant shadow. Furthermore, there is a problem in that device-specific parameters must be selected for each device, making it difficult to generalize manufacturing conditions.

On the other hand, in recent years, deposited films (functional deposited films) used in various electronic devices are required to have uniform film quality over a large area, and mass production has become a social demand, and plasma CVD method Therefore, mass production of such large-area deposited films requires a large capital investment in mass production equipment, and the management items for mass production also become complex, the management tolerance narrows, and equipment adjustments are delicate. Therefore, there is a problem in that the resulting deposited film is expensive.

For these reasons, as a method that can replace the above-mentioned plasma CVD method, for example, as seen in Japanese Patent Application Laid-Open No. 6197813, hydrogen radicals in an excited state are used as a raw material gas for film formation or in an activated state. A method of forming a film at a high deposition rate by reacting with
CV D Method), and JP-A-55-14.
As seen in Publication No. 1729 or Japanese Patent Application Laid-Open No. 57133636, an electromagnet is placed around the cavity resonator,
A method of efficiently forming a film by using microwaves to establish ECR (electron cyclotron resonance) conditions to generate high-density plasma (hereinafter referred to as "EC
``R method'') has been proposed.

Both the HR-CVD method and the ECR method have been evaluated as effective for mass production of deposited films in place of the plasma CVD method, and various studies have been conducted. In order to enable steady mass production, there are several problems that need to be solved with either method.

In other words, in the HR-CVD method, which is highly evaluated among the two methods, the excited hydrogen radicals generated as described above are reacted with the raw material gas for film formation or its activated state to form a deposited film. However, the reactivity of some types of film-forming raw material gases with hydrogen radicals is extremely low, and there is a problem in that there are restrictions on the film-forming raw material gases that can be used. If you try to transport the activated source gas to the deposition space after exciting the source gas away from the deposition space, the activated state has a short lifetime and only a small amount reaches the deposition space. There is also the problem.

In addition, the microwaves generated by the microwave power source have
Usually, ripples are superimposed, and these ripples cause the plasma to become unstable, resulting in a deposited film with poor or inconsistent properties.

[Purpose of the invention]

The present invention solves the above-mentioned problems in conventional deposited film forming methods, and provides functionality using a microwave plasma CVD method that enables stable mass production of functional deposited films with desired characteristics and good reproducibility. The main purpose of the present invention is to provide a method for forming a chemically deposited film.

Another object of the present invention is to easily control the excited state of a hydrogen atom, and to achieve zero! It is an object of the present invention to provide a method for forming a functional deposited film using a microwave plasma CVD method, which enables stable mass production of a desired functional deposited film at -temperature.

A further object of the present invention is to provide excited hydrogen atoms in a cavity resonator integrated with two impedance matching circuits in a microwave three-dimensional circuit using hydrogen gas or a mixture of hydrogen gas and a rare gas. By controlling the excited state of hydrogen atoms generated by microwave plasma generated in a plasma generation chamber, stable mass production of functional deposited films with desired characteristics and good reproducibility is possible. It is an object of the present invention to provide a method for forming a functional deposited film using a microwave plasma CVD method that enables the following.

[Structure and effects of the invention]

The inventor of the present invention solved the above-mentioned problems in the conventional deposited film forming method and conducted extensive research to achieve the object of the present invention, and found that two impedance matching circuits were integrated into a three-dimensional microwave circuit. In this method, a plasma generation chamber is provided in a cavity resonator, and a microwave plasma discharge is performed using hydrogen gas or a gas mixture with hydrogen gas. By injecting microwave energy into the membrane space, we found that a desired functional thin film could be formed stably and efficiently.

The present invention has been completed through further research based on this knowledge. The gist of the present invention is as described above.

That is, in a film forming space for forming a deposited film on a substrate, a silicon-containing compound (1) which is a raw material for forming a deposited film and, if necessary, a compound represented by the following general formula (1) ( 2) and, if necessary, a compound (3) containing an element capable of controlling valence electrons in the deposited film, each of which is introduced in a gaseous state into the film forming space, and these compound (1), the compound (2) and compound (3) in the film-forming space, and at the same time, hydrogen atoms in an excited state that chemically react with at least one of these compounds (1), (2), and (3) are activated in the film-forming space. A method for forming a functional deposited film, in which hydrogen atoms in an excited state are generated in an activation space different from a film-forming space, and are introduced into the film-forming space to form a deposited film on the substrate. Hydrogen gas or a mixture of hydrogen gas and rare gas is used to generate microwave plasma in a plasma generation chamber installed in a cavity resonator integrated with two impedance matching circuits in a three-dimensional microwave circuit. , and a deposited film forming method characterized by controlling the excited state of generated hydrogen atoms.

A a B b---------(I) (However, A represents an element other than silicon among the elements belonging to Group II of the periodic table, and B represents hydrogen (H), halogen ( X) indicates one selected from hydrocarbon groups, a indicates a positive integer equal to or an integral multiple of the valence of B, and b indicates a positive integer). The energy input into the chamber and the energy input into the plasma generation chamber are divided into two from the same microwave power source by a power divider, and one energy is input into the deposition chamber, and the other energy is input into the plasma generation chamber. By supplying it to the plasma generation chamber, the adverse effect of ripples generated by the microwave generated by the microwave power source on film formation can be minimized.

According to the deposited film forming method of the present invention, when forming a desired functional deposited film, the above-mentioned compound (11) and the above-mentioned (2) are added into the film-forming space in a gaseous state or an activated state.
Furthermore, if necessary, a compound (3) containing an element capable of controlling the valence electrons of the deposited film as a constituent and a hydrogen atom whose excited state is controlled separately from these are introduced, and by causing a chemical reaction between them, A functional deposited film is formed. At that time, by appropriately controlling the excited state of hydrogen atoms, the crystallinity and hydrogen content of the deposited film formed can be controlled stably and with good reproducibility. The excited state of atomic hydrogen in the present invention is determined from the light emission observed in microwave plasma of a mixed gas of hydrogen gas and rare gas, and specifically, the excited state of atomic hydrogen is determined from the light emission observed in microwave plasma of a mixed gas of hydrogen gas and rare gas. Among the emission lines of atomic hydrogen (H) measured by emission spectrometry, 656n attributed to Ho
Focusing on the 486 nm emission line belonging to m and 11β, the excited state is determined based on the intensity ratio of the two (1-1 e/Hβ). In order to obtain the desired intensity ratio (Hct/Hβ), the microwave input power into the cavity resonator, the impedance matching conditions, the hydrogen gas flow rate or the mixed flow ratio of hydrogen gas and rare gas, and the total This is done by controlling one or more pressure parameters to predetermined values.

In the method of the present invention, in order to control the excited state of hydrogen atoms to a desired state, the intensity ratio of 11ct/Hβ is preferably 1/1 to 1000/l and optimally 10/1 to 500.
It is desirable to control it to /1.

In addition, in the method of the present invention, the intensity ratio of Hct/Hβ is set within the above-mentioned range, and the combination of substrate type and substrate temperature is a factor that determines film quality, etc., and desired film quality can be achieved by appropriately combining these factors. A deposited film having film characteristics is formed. Note that the intensity ratio (H/Hβ) is measured using an emission spectrophotometer.

In the method of the present invention, the microwave plasma monitor monitors the compounds (1), (2) in the flow direction of all gases.
and (3) at a position upstream of the gas blowing means. Therefore, it is possible to stably monitor from the start of film formation to the end of film formation in a place where substantially no deposited film is formed.

The above compounds (1) and (2) used in the present invention
In addition, the compound (3) containing an element capable of controlling the valence electrons of the deposited film is a compound (3) that causes molecular collisions with the excited hydrogen atoms in the space where the film-forming substrate is located. Those that cause a chemical reaction and produce chemical species that contribute to the formation of the deposited film formed on the substrate are selectively used.

In the present invention, the compounds (1) and (2) that can be effectively used include the following.

That is, when forming a deposited film containing semiconducting atoms of group Ⅰ of the periodic table by the method of the present invention, the silicon-containing compound (11 is, for example, a hydrogen atom of a chain or cyclic silane compound). Compounds partially or completely substituted with halogen atoms may be mentioned, such as 5i
uYzu. z (u is an integer of 1 or more, Y is F, Cn, Br
Or I. ), S iv HX Y v (v is an integer of 3 or more, Y
has the meaning given above. ), a cyclic silicon halide compound represented by S9Hxyu (u and Y have the above-mentioned meanings).

xy=2u or 2u+2. ) is a chain or cyclic compound represented by

Specific examples of these compounds include, for example, SiH4+5iF
a + (SiFz)s + (SiFz)6. (Si
Fz)4゜5izF6,5i3FI], SiHF3.5
iH2FzSizHzF4+5izH:+Fz, SiC
β4. ．． (S i Cj22) 51SiB r a
, (SOB r 2)S I SiCII b +
SiHCII: l+5iHBrz, 5iHzCAz
,5iCj! 3F3 etc.

The compound (2) represented by the general formula (I) is an element belonging to Group Ⅰ of the periodic table, specifically, G e
Examples include compounds containing + C and S u + P b as constituent atoms. Among these compounds, compounds containing Ge as a constituent atom include G e u Y z u
+2 (U is an integer greater than or equal to 1, Y is H, F, C1!,
At least one element selected from Br and I. ), linear germane or germanium halide represented by GevY2. Cyclic germane represented by (v is an integer of 3 or more, Y has the above-mentioned meaning) or germanium halide, GeuHxYu (U is an integer of 1 or more, Y is selected from F, Cβ, Br, or ■ Examples include chain or cyclic germanium compounds represented by at least one element, xy-2u or 2LI+2), and organic germanium compounds having an alkyl group.

Specifically, these compounds include, for example, GeHa+G
ezH6Ge3HB , n GeH+o , t G
etHHo, GeHb +Ge5H+o+ GeN3
C(1, GeHzF2, Ge(CH3)4゜Ge(C
zHs)4.0eCCbHs)a, Ge(CH3)Z
Fz.

These include GeFz, GeF, +GeS, etc.

Examples of compounds containing C as a constituent atom include compounds in which part or all of the hydrogen atoms of a chain or cyclic hydrocarbon compound are replaced with halogen atoms, such as Cu Y
2 u + 2 (u is an integer greater than or equal to 1, Y is HF,
At least one element selected from Ca, Br and I. ) and the like. These compounds specifically include, for example, CHa, CF4
, (CF2)S, (CF2)6. (CF2) 4°Cz
F6. C3F[l, CHF: r l CHzFz.

C2H2F4, C2H3F3, CClla
, (CCIIz)s.

CBr, (CBr2)s + CCn6, CHCn
:+.

CHB r 21 CH2CII 21 CCj!
s F * etc.

Regarding the compounds (11 and (2)), the above-mentioned compounds can be used alone, or two or more types can be used as necessary.

In the method of the present invention, the compound (3) containing a component serving as a valence electron control agent is in a gaseous state at room temperature and normal pressure, or at least in a gaseous state under deposited film forming conditions, and is subjected to appropriate vaporization. Compounds that can be easily vaporized in the equipment are selectively used.

And such compound (3) is 1, which is number 1 in the periodic table.
When obtaining a group deposited film, compounds containing elements of groups 1 and 2 of the periodic table can be cited as effective. Specifically, the compounds containing group (■) include BX3, B2H6,
B4H+o, B5H95B5H++.

B b H+. , B(CH3)3 , B(CzHs)a
,B6H,Z.

ArXs, A (1(CH,1)zC7!, A
r(cH:1)3Aβ(OCHa)2Ca, Ar(
CH,)Cβ2. Ar(CzHs):+Aρ(OCzHs)
s)3. Ar(CHz)+Cn:+AlC4C4HJs
+AA(C3H7)s+Aβ(OC4H9) 3°Ga
X3 , Ga(OCH3)3 + Ga(OCzHs)
3+Ga(OCiHq)i l ca(cH3:'3
,GazHbGaH(CzHs)z ,Ga(OCzH
s), (CzHs)z.

In(CH:+)3. In(C3H7), 3+ 1n
(CaHq)* etc. Moreover, as a compound containing a group V element, NN3HN3. N2H5N:l, N2H&
, NHaN3゜px,,P(OCH3)! ,P(OC
zHs)+.

P(C31-+7CI, P(OCzHJs, P(C
H3)3.

P(C2T(5)3, P(C3Hff)3,
P(C4H9)3.

P(OCH,)3. P(OC2H5):l, P(OC
3Hff)3.

P(OC4H9)ff, P(SCN)+, PZH4
, PH3.

AsH3, ASX3. As(OCN3)31 AS(
OC2H3)3+AS(OC3H7)! + As(O
CaHq)++ As(CN3)3 +AS(C2H5
)3. As(C6H5)315bXa, 5b(OCN
3) 3Sb(OC2H3):l, 5b(OC:lH?
)3.5b(OC4H9)3゜5b(CN3)z,
5b(C3H7)s, 5b(C4HqL+, etc.).
, C(1,Br,I).

As with the above compounds (1) and (2), these compounds belonging to compound (3) may be used alone or in combination of two or more as necessary.

If the above-mentioned raw material is in a gaseous state at room temperature and normal pressure, the amount introduced into the film forming space or activation space is controlled by a mass flow controller, etc., and if it is in a liquid state, a rare gas such as Ar or He is used. Alternatively, hydrogen gas is used as a carrier gas and gasified using a bubbler that can control the temperature as necessary.If it is in a solid state, Ar,
A rare gas such as 1-1e or hydrogen gas is gasified as a carrier gas using a heating sublimation furnace, and the amount introduced is controlled mainly by controlling the carrier gas flow rate and temperature.

The excited hydrogen atoms used in the method of the present invention are the compound ( 1) and (2) or/and chemically interacts with the excited state of the compound (1) or/and the excited state of the compound (2). As a result, a deposited film of group I of the periodic table having desired functionality can be easily formed on a desired substrate at a lower temperature than in the past.

In the present invention, hydrogen gas or a mixed gas of hydrogen gas and a rare gas is used to generate excited hydrogen atoms. When microwave plasma is not stabilized or plasma is not generated using only hydrogen gas, it is effective to mix a rare gas as appropriate.

The rare gases include He, Ne, Ar, Kr+Xe,
Rn is preferred.

Next, the method of the present invention uses a microwave plasma CVD device having a cavity resonator structure integrated with two impedance matching circuits in a microwave three-dimensional circuit, as described below.
This is preferably carried out using a device.

First, for comparison, conventional microwave plasma CVD
The method for forming a deposited film using the method will be described below.

FIG. 2 is a schematic explanatory diagram of a typical example of an apparatus used to carry out a deposited film forming method using a conventional microwave plasma CVD method.

In FIG. 2, 201 is a rectangular waveguide, 202 is a microwave introduction window, 203 is a plasma generation chamber, 204 is a film forming chamber, 205 and 210 are gas supply pipes, 206 is an exhaust port, 20
Reference numeral 7 represents an object to be processed, 208 a holder for the object to be processed, and 209 a metal mesh.

As shown in FIG. 2, the apparatus is composed of a plasma generation chamber 203 using microwaves and a film formation chamber 204 using plasma. The transmission of microwaves and charged particles is restricted so that they do not directly enter the film forming chamber 204. The plasma generation chamber 203 has a cavity resonator structure, and the microwaves propagated through the rectangular waveguide 201 are passed through the microwave introduction window 202 made of a dielectric material such as quartz, alumina ceramics, or Teflon. and introduced into the plasma generation chamber 203. A processing object (substrate) 207 is arranged in the film forming chamber 204, and a gas supply pipe 205 and an exhaust port 2 for exhausting the plasma generation chamber 203 and the film forming chamber 204 are provided.
06 is provided.

In the film formation operation using the apparatus shown in FIG. 2, microwaves are introduced into the plasma generation chamber 203 from the rectangular waveguide 201, and hydrogen gas etc. It turns into plasma due to the electric field energy of the waves and generates hydrogen atoms in an excited state. There is a metal film inside the film forming chamber 204.

The excited hydrogen atoms generated through the gas introduction pipe 209 are introduced, and the hydrogen atoms are separated from the raw material gas supplied from the gas introduction pipe 205 by 1 m.
A chemical reaction suddenly occurs, and a deposited film is formed on the substrate 207.

However, the conventional microwave plasma C with the above configuration
In the VD device, when the rectangular waveguide 201 and the plasma generation chamber 203, which is a cavity resonator, are connected, the input impedance is not matched, so most of the electric field energy of the microwave is reflected, and the energy cannot be used effectively. The problem is that it doesn't work.

As a means to solve the above-mentioned problems, the present inventor created a structure that can operate as a cavity resonator regardless of the presence or absence of plasma or the plasma density, and provided a Pelger serving as a plasma generation chamber within the cavity resonator. , found that it is effective to excite the TM mode.

Specifically, we have found that it is sufficient to provide a variable cavity length plunger in the cavity resonator structure, and to connect the rectangular waveguide so that its axes are perpendicular to each other, as shown in FIG. Furthermore, in the case of impedance matching, in combination with the variable cavity length one lanzier, at the connection part between the rectangular waveguide and the cavity resonator, the impedance matching is performed. It has been found that it is preferable to employ either an E-H tuner or a three-stub tuner.

That is, the herger for plasma generation disposed within the cavity resonator is made of a material that is transparent to microwaves. Specifically, materials that can maintain airtightness, such as quartz, alumina ceramics, boron nitride, silicon nitride,
The Pelger is made of so-called new ceramics such as silicon carbide, beryllia, magnesia, and zirconia.

Further, the variable cavity length plunger is provided on the microwave introducing side, that is, on the atmosphere side, with respect to the Pel jar. In this way, impedance matching can be performed by changing the cavity length in the atmosphere, so the cavity length can be easily adjusted in response to changes in the cavity conditions due to the presence or absence of plasma or changes in plasma density, with good reproducibility. Microwave plasma can be generated stably.

In this method, the metal mesh provided between the herger and the film-forming space has the role of an end plate to establish cavity resonance conditions, so the diameter of the metal mesh is adjusted to the wavelength of the microwave used. It is preferably λ/2 or less, most preferably λ/4 or less.

Examples of the shape of the metal mesh include a wire mesh shape, a thin metal plate with round or polygonal holes, and its constituent materials include Aβ, Fe, and Ni.

It may be composed of so-called single metals such as Ti, Mo, W, Pt, Au, Ag, and stainless steel, or it may be composed of glass, ceramics, or metal composites that have been surface-treated with the aforementioned metals by plating, sputtering, vapor deposition, etc. It may be the body.

Further, it is preferable that the hole diameter and distribution of the metal mesh are changed in order to efficiently and uniformly introduce the excited hydrogen atoms generated in the Herjar into the film forming space. The total aperture ratio at this time is preferably 10% or more, more preferably 20% or more, and optimally 30% or more.

Furthermore, in order to improve the uniformity of film thickness distribution and film properties,
In this invention, gas blowing means for compounds (1) and (2) and, if necessary, compound (3), is important. Specifically, as shown in FIG. 1, it is preferable to use a gas blowing ring formed by a ring arranged coaxially with the herger and the substrate, and the ring has a gas blowing hole for releasing gas. . The gas outlet holes are designed as desired so that the gas is released uniformly. In the present invention, conditions for stably generating microwave plasma of hydrogen gas or a mixed gas of hydrogen gas and a rare gas, and selected types and states of compounds (1), (2) and (3); The internal pressure of the film-forming space during film-forming is determined as appropriate based on the desired characteristics of the deposited film, but is preferably 1.
00 to I
-5X 10-'Torr, optimally 1 to 1x10-
It is desirable that the pressure be set at 3 Torr.

Based on the above-mentioned means for generating hydrogen atoms in an excited state, the inventors of the present invention conducted further intensive studies, and as a result, provided a film-forming chamber connected to the cavity resonator structure, and introduced a raw material gas into the film-forming chamber. It has been found that by activating these source gases in the film forming chamber, a deposited film of good quality can be produced and the deposition rate can also be improved.

In the present invention, heat, light, discharge energy, etc. are appropriately selected and used as the energy input into the film forming chamber to activate compound +1+, compound (2), and compound (3). Specifically, for example, thermal energy such as resistance heating, infrared heating, laser light, mercury lamp light, light energy such as halogen light, microwave, RF
, low frequency, DC discharge energy, etc. are used, and in particular, by using microwave discharge energy, a deposited film of good quality can be stably produced with good reproducibility. Furthermore, by installing a power splitter in the microwave power source, the microwave energy is split, and one side of the energy is input into the plasma generation chamber, and the other side is input into the film formation chamber, thereby reducing ripples contained in the microwave. This makes it possible to form a film stably without any problems.

In the present invention, in order to stably establish the cavity resonance condition, the oscillation mode in the microwave oscillator is continuous oscillation,
Preferably, the ripple width in the used output area is 30
It is desirable that it be within %.

According to the present invention, a deposited film having desired crystallinity can be formed on any crystalline substrate, regardless of whether it is amorphous or crystalline.

A typical example of a deposited film forming apparatus suitable for carrying out the present invention will be described below, but the present invention is not limited to this deposited film forming apparatus.

FIG. 1 is a schematic diagram of a deposited film forming apparatus suitable for carrying out the present invention.

In FIG. 1, 101 is a cylindrical cavity resonator, and its main components include a Pelger 102 serving as a microwave plasma generation chamber, a metal mesh 103, a variable cavity length plunger 104, a rectangular waveguide 108, and an aperture 110. has been done.

105 is a phosphor bronze spring provided to improve the contact between the plunger 104 and the cylindrical cavity resonator 101;
Prevents abnormal discharge. Cavity length variable plunger 10
4 can be moved toward the Pelger 102 by a motor 106 and a transmission gear 107. 10
9 is an E-H tuner or a three-stub tuner, which constitutes one of the impedance matching circuits constituting the microwave three-dimensional circuit in the present invention, and a variable cavity length plunger 10 which is one of the other impedance matching circuits.
Used in pair with 4.

The aperture 110 includes a rectangular waveguide 108 and a cylindrical cavity resonator 10.
A pair of left and right rectangular waveguides 108 are provided at the connection part with 1, and each independent rectangular waveguide 108 can be slid along the cylindrical surface in the longitudinal direction. Contact with the container 101 is maintained.

The microwave generated by the microwave power supply 126 is
The power is transmitted through a waveguide 127 to a power divider 128 and divided at an appropriate ratio. After that, one side is put into the cylindrical cavity resonator 101, and the other one is put into the film forming chamber 116. A blowout hole for hydrogen gas or a mixed gas of hydrogen gas and a rare gas from the gas introduction pipe 111 is directed into the bell jar 102 through a metal mesh, and the hydrogen gas etc. introduced into the bell jar 102 resonates in the cavity. vessel 10
The hydrogen atoms are turned into plasma by the microwaves injected into the metal mesh 103 , generate excited hydrogen atoms, and are introduced into the film forming space 116 through the metal mesh 103 . The pressure within the film forming space is measured by a pressure gauge 125.

In the film forming space 116, a raw material gas blowing ring 112 for forming a deposited film is connected to a substrate 118 and a substrate holder 119.
is placed between.

The gas blowing ring 112 has a gas blowing hole 113.
is provided.

The deposited film forming raw material gas introduced into the film forming space 116 is exhausted by an unillustrated exhaust pump in the direction of the arrow in the figure.

A boat 121 is provided for a microwave plasma monitor, and a light collecting probe 122 is connected thereto.

A quartz fiber 123 is connected to the light collecting probe 122, which is further connected to a spectrometer (not shown) to perform emission spectroscopic analysis. 124 is a spare port for plasma monitoring on the film forming space side.

In the present invention, to control the excited state of hydrogen atoms,
The combination of the intensity ratio of H, x/Hβ, the type of substrate, and the substrate temperature is a factor that determines the film quality, and by appropriately combining these, desired film quality and film characteristics can be formed.

The above points can be understood from consideration through experiments described below.

〔experiment〕

Using the apparatus shown in FIG. 1, the following experiments were conducted regarding the excited state of hydrogen, substrate temperature, and type of substrate.

H2 gas l Qsccm from the gas supply pipe 111, A
rl 00 sccm was supplied, and microwaves were input from the rectangular waveguide 108. The substrate 118 has a plane orientation (1,10)
A silicon wafer and a Corning 7059 glass substrate were used, and the substrate temperature was 250°C.

The microwave power input from the rectangular waveguide 108 is 50
The power was varied from W to 350 W, and the emission of plasma generated in the Pelger 102 was guided to a visible spectrometer (not shown) through a quartz fiber 123 to monitor Hct and Hβ.

The power input from the rectangular waveguide 129 was 100 W, and 100% of S i F 4 gas was supplied from the gas supply pipe 120.
It was supplied to the film forming space 116 at a flow rate of 105e.

The internal pressure within the film forming space 116 was set to 0.05 Torr.

This state was maintained for 60 minutes, and a thin film was deposited on the substrate 118. A portion of the obtained sample was evaluated for crystallinity by X-ray diffraction and electron beam diffraction (RHEED). In addition, a comb-shaped aluminum gap electrode (250 μm in length, 5 fins in width) was deposited on a part of the sample by resistance heating using a vacuum evaporator, and the dark conductivity σd was measured at an applied voltage of 10 μm.
The cutting conductivity σp was measured by irradiating with eNe laser light (5 mW), and the ratio σp, /σd was determined. The deposition rate was also determined from the sample film thickness.

The results obtained are shown in FIGS. 3 and 4.

Figure 3 shows the degree of excited state of hydrogen during film formation in a sample deposited on a Corning 7059 substrate.
The ratio σp/σd of d and the deposition rate are plotted. This figure shows that HCt/Hβ is 1/1 to 1000/1.
It has been found that when the ratio is within the range of 10/1 to 500/1, a film with good electrical properties and a fast deposition rate can be obtained, and in particular, a film of better quality can be obtained when the ratio is between 10/1 and 500/1. Note that all the samples were amorphous.

Next, Figure 4 shows the Hcc/
It shows the deposition rate for Hβ.

Table 1 also shows the values of H, /Hβ and the RHE of the obtained samples.
The correspondence with the crystallinity evaluated by ED is shown.

According to Figure 4 and the table, the value of Hct/He is 1/1 to 10.
It was found that when the ratio was within the range of 00/1, good quality crystals were obtained and the deposition rate was fast.

Next, the following experiment was conducted to examine the effect of substrate temperature on the crystallinity of the deposited film.

[■] using the silicon substrate described above. /f (β ratio is 20
Microwave power was applied so that it became 0.

Further, the substrate temperature was varied from 200°C to 350°C, and the other conditions were the same as in the above-mentioned method to prepare each sample.

The crystallinity of the obtained sample was observed using RHEED and the results are shown in Table 2. This result shows that the substrate temperature greatly affects the crystallinity of the deposited film.

According to the above experiments, in the present invention, in order to control the excited state of hydrogen atoms, the intensity of Ha/He is preferably 1/
1-1000/1, more preferably 10/1-500/
It has been found that it is desirable to control it to 1.

〔Example〕

The deposited film forming method of the present invention will be described below with reference to specific examples.

Note that the present invention is not limited to this example.

First, a Corning #7059 glass substrate 118 with a diameter of 150 mm is placed on the substrate holder 119 in the film forming space 116, and is evacuated using an exhaust pump (not shown).
The pressure inside 16 was set to 1×1O−6 Torr. Further, the substrate holder was heated by a substrate temperature controller (not shown), and the surface temperature of the substrate 118 was set to 250.degree.

When the substrate surface temperature stabilized, 20 sccm of H2 gas and 200 sccm of Ar gas were supplied to a gas pump (not shown).
The mixed state is introduced into the quartz herbal jar 102 through the gas introduction pipe 111, and then the SiF gas 10105e is passed through a gas cylinder (not shown) and introduced into the film forming space 116 through the gas supply pipe 120 through the gas blow ring 112. did. At this time, the pressure inside the film forming space 116 is Q, 4
It was controlled by an automatic pressure controller to maintain Torr.

The distance between the substrate 118 and the metal mesh 103 is 100 inches.
and set them so that they are parallel to each other.

The metal mesh 103 is made by Aff and has a total diameter of φ150, φ
A punching board with an aperture ratio of 50% in which 8 holes were uniformly distributed was used. The gas blowing ring 112 is shown in FIG.
In the configuration shown in , the hole diameter corresponding to 201a and 201a is 1
．． 5 + u, and the hole diameter was uniform.

Next, a continuous wave microwave oscillator 126 generates microwaves, and a rectangular waveguide 127 and a power divider 128
Microwaves were injected into the cavity resonator 101 via. Immediately, the variable cavity length plunger 104 is operated by the motor 106 and the variable speed gear 107 to a position where the ratio of reflected power/incident power measured by a power monitor installed in the microwave three-dimensional circuit (not shown) is the smallest. Further, the opening degree of the diaphragm 110 was adjusted to a position where the ratio of reflected power/incident power is the smallest. The operation of finely adjusting the position of the variable cavity length plunger 104 and the opening degree of the aperture 110 is repeated again until the ratio of reflected power/incident power is the smallest and the value of effective incident power expressed as incident power - reflected power is 100 W. I arranged the wording so that

At this point, the intensity ratio of the emission line ■(.) and Hβ (HCx
/Hβ) was 50.

Furthermore, the generated microwave was introduced into the film forming chamber 116 via the rectangular waveguide 129 and the matching device 130. Immediately, the matching device 130 is adjusted so that the ratio of reflected power/incident power measured by a power monitor installed in the microwave three-dimensional circuit (not shown) becomes the smallest, and then the aperture 13 is adjusted.
The opening degree of No. 1 was adjusted to the position where the ratio of reflected power/incident power was the smallest. Adjustment was made so that the value of effective incident power expressed as incident power minus reflected power was 50W.

A chemical reaction immediately occurred between the hydrogen atoms in the excited state and 5iFa, and a film with a thickness of 7.5 μm was formed on the substrate 1081 in 60 minutes. After cooling the substrate, take out sample No.
The score was 1-1.

Next, another #7059 substrate was placed at a temperature of 70 cm, the gas flow rate was 20 sec, and the pressure in the film forming space was 0.05 Torr.
The deposited film was formed using the same procedure except that the substrate temperature was set at 270°C. At this time, the intensity ratio T(,/Hβ is 1
It was 00. After 60 minutes of deposition, the substrate was taken out and designated as sample 1-2.

Furthermore, a 6-inch n"Si (110) wafer was used as the substrate, the H2 gas flow rate was 100 sec, the Ar gas flow rate was 50 sec, and the pressure in the film forming space was 0.01 T.
The deposited film was formed using the same procedure except that the opening ratio of the punching board was changed to 30%.

The intensity ratio I-■o/Hβ at this time was 40. The obtained sample was designated as floor 1-3.

Next, for comparison, similar film formation was performed using the apparatus shown in FIG. 2 in the following manner, and the sample was exploded.

Film formation was performed in the same manner as described above except as described below.

Corning #7059 glass substrate 207 with a diameter of 150 mm
is installed on the substrate holder 208 in the film forming space 204,
The vacuum was evacuated using an exhaust pump (not shown), and the pressure inside the film forming space 204 was set to IX 10-6 Torr. Furthermore, the substrate holder is heated by a substrate temperature controller (not shown),
The surface temperature of the substrate 207 was set to 250°C.

When the substrate surface temperature stabilized, 20 sccm of H2 gas and 200 sccm of Ar gas were supplied to a gas cylinder (not shown).
The mixed state was introduced into the plasma generation chamber 203 through the gas introduction pipe 210 1, and then SIF 4 gas was introduced into the gas supply pipe 205 from a gas cylinder (not shown) at a flow rate of 10105e. An infrared heating furnace 212 is disposed in the gas supply pipe 205, and the inside of the activation space 211 is maintained at 700° C. to excite SiFa gas and transfer SiF4 in an excited state to the film forming space 204 via the transport space 205. introduced gas.

At this time, the pressure inside the film forming space 204 is Q, 4 Torr
It was controlled by an automatic pressure controller to maintain r.

Subsequently, a continuous wave microwave oscillator (not shown) generated microwaves, and the microwaves were introduced into the plasma generation chamber 203 via the rectangular waveguide 201 and a matching device (not shown). Adjustment was made so that the value of effective incident power expressed as incident power minus reflected power was 100W.

Immediately, the excited hydrogen atoms and the S i Fa gas generated a chemical reaction and were deposited on the substrate 207 for 60 minutes. The substrate was cooled and taken out to provide sample separation 14. Furthermore, in the same manner as described above, the H2 gas flow rate was increased to 2Qsccm.
A deposited film was formed using the same procedure except that the pressure in the film forming space was set to 0.05 Torr% and the substrate temperature was set to 270° C. After 60 minutes of deposition, the substrate was taken out and used as sample No. 1-5. Finally, a 6-inch n"Si (110) wafer was used as the substrate, and the H2 gas flow rate was 100 sec = A
The r gas flow rate was set to 50 seconds, and the pressure in the film forming space was set to 0.
OI Torr and punching board aperture ratio 30
A deposited film was formed using the same procedure except that the sample was designated as 1-6.

The film thickness of each of the obtained deposited film samples was measured using Alpha Step manufactured by TENCOR, and the deposition rate was calculated. Furthermore, the crystals of the deposited film were evaluated by X-ray diffraction and electron beam diffraction (RHEED). The evaluation results were as shown in Table 3. All films of each sample were homogeneous.

Furthermore, the films at sample points 1-1 and l1hl-4 are amorphous films, the films at sample points 1-2 and 1-5 are polycrystalline films, and the films at sample points 1-3 and 1-6 are polycrystalline films. It was confirmed that these were epitaxial films whose planes parallel to the substrate had an orientation close to (110).

In addition, a portion of each sample was cut out and analyzed using a secondary ion mass spectrometer (SIMS) to determine the film composition and hydrogen CI.
() The content was investigated. The results are shown in Table 3. Regarding the H content, sample tooth 1-1, sample point 1-2,
It was found that the number of teeth decreases in the order of sample teeth 1-3.

Further, each sample was placed in a vacuum evaporator, a 211Iφ dot electrode of aluminum was deposited by a known resistance heating method, and the hole mobility (μ) was measured by the Van DerPauw method. The measurement results were as shown in Table 3.

Note that the values of deposition rate and hole mobility shown in Table 1 are relative ratios.

That is, sample tooth 1-1 is a relative ratio to sample tooth 1-4, sample point 1-2 is a relative ratio to sample teeth 1-5, and sample No. 1-3 is a relative ratio to sample tooth 1-6. It is a relative ratio to

In addition to the above, sample point 1-1, sample tooth 1-2, and sample point 1-
When we investigated the distribution of 11 content and hole mobility values for each film of No. 3, it was found that the dispersion of these values was within ±3% in all cases, which was good.

From the above results, it was found that the crystallinity of the deposited film can be easily controlled by the present invention, and the deposition rate is improved compared to the conventional method.

Melanoma 1 By the same operation as in Example 1, S i
:Ge:H:F film was formed. Flow 10105e of 3iF gas into a gas pump (not shown), and then flow GeF4 gas into another gas pump (not shown). J! The mixed gas was introduced into the film forming space 116 from the gas blow ring 112 through the gas supply pipe 120 with a velocity of 3 seconds. At this time, the pressure inside the film forming space 116 is 0.6 Ta
It was controlled by an automatic pressure controller to maintain rt. A continuous wave type microwave oscillator 126 injected microwaves with an effective incidence type cuff of 5 W into the cavity resonator 101 . At this point, the intensity ratio (H/Hβ) of the emission line from excited state hydrogen atoms observed from Po 1-121 was 30.

Furthermore, the film was formed under the same conditions as those used for producing sample N11l-1 in Example 1, except that the generated microwave was injected into the film forming chamber 116 through the rectangular waveguide 129 and the matching box 130 to a power of 30 W. membrane was performed. The obtained sample was designated as patient 2-1.

Next, the flow rate of G e Fa gas was set to 5 sccm and 7 sccm.
The film was formed three times in the same manner as described above, except that sccm and 10105c were used.
2.11k1.2-3, positive 2-4.

The film thickness distribution of each of the obtained deposited film samples was measured, and the crystals of the deposited film were evaluated by X-ray diffraction and electron beam diffraction (RHEED). Each sample had good uniformity and was confirmed to be an amorphous film.

In addition, a portion of each sample was cut out and analyzed using a secondary ion mass spectrometer (
Composition analysis was performed using SIMS to determine the composition ratio of Si and Ge, and the optical hand gap was determined by measuring the optical absorption spectrum of each sample using a visible spectrometer. Each characteristic was within a range of approximately ±2% in the plane. The above results are shown in Table 4. This result shows that by changing the gas flow rate, it is possible to arbitrarily change the composition ratio of Si and Ge, and it is also possible to control the optical hand gap.

From the above results, it was found that the optical film quality of the deposited film can be easily controlled by the present invention.

In the same manner as in Example 1,
The microwave input power was 200 W, and the Si:C:H:F film was formed under the conditions described below.

The substrate is a #7059 glass substrate with a diameter of 150 mm.
F6 gas was introduced into the film forming space at a flow rate of 15 sec; CHaHe gas sccm, and the pressure inside the film forming space was set to 0.01 T.
orr and the substrate temperature was set at 260°C. The gas blow ring, metal mesh, and substrate positions were the same as in Example 1, and film formation was performed for 60 minutes.

Next, add 5% of BFff gas diluted to 10% with He gas.
The film was formed in the same manner as described above except that sec was added. Both Hct/Hβ ratios during film formation were 180. The obtained samples were named Arashi 3-1 and Arashi 3-2.

Next, the H2 gas was set at 100 sec and the internal pressure was set at 0.03 T.
The sample obtained by forming a film in the same manner as sample 3-2 except that orr was used was designated as positive 3-3.

Next, films were formed in the same manner as described above except that the apparatus shown in Fig. 2 was used, and the obtained samples were respectively NO3-4 and NO3-4.
Patients were designated as patients 3-5 and 3-6. The obtained sample was evaluated for crystallinity and H content in the same manner as in Example 1, and further thermoelectromotive force was measured to determine the conductivity type. Separately, a portion of each sample was cut out, placed in a vacuum evaporator, a comb-shaped aluminum gap electrode (250 μm in length, 5 mm in width) was deposited, and the dark conductivity was measured with an applied voltage of 10 V, and then HeN e The gate conductivity was measured by irradiating laser light (5mW) and the dark conductivity (
The ratio (σp/σd) of the gate conductivity (σp) to the gate conductivity (σp) was determined. The results were as shown in Table 5.

Note that both the values of σp/σd and the values of deposition rate shown in Table 5 are relative ratios.

That is, for sample N6.3-1, sample No. 3-4
Sample floor 3-2 is a relative ratio to sample floor 3-5, and sample N113-3 is a relative ratio to sample floor 3-5.
is the relative ratio to sample floor 3-6. Also,
For each of sample teeth 3-1, No. 3-2, No. 3-3, H content and dark conductivity σ on the entire surface of the sample.
When the distribution state of the values of d and portal conductivity σp was investigated, it was found that the variation was within ±3% in all cases, indicating good uniformity.

From the above results, it was found that according to the present invention, the conductivity type of the deposited film can be easily controlled, and the electrical characteristics can also be controlled. It has also been found that the film formation rate can be improved compared to conventional film formation methods.

Heaven hf! i[I14 A deposited film was formed using the same operations and film forming conditions as in Example 1, except that some of the raw material compounds for forming the deposited film and the film forming conditions were replaced with those shown in Table 6.

For comparison, a deposited film was formed in the same manner using the apparatus shown in FIG. The obtained samples were evaluated in the same manner as in Example 3, and the samples produced using the apparatus shown in Figure 1 and the samples produced using the apparatus shown in Figure 2 were compared, and the results shown in Table 7 were obtained. .

From the above results, it is possible to easily control the conductivity type of the deposited film according to the present invention, and it is also possible to improve the electrical characteristics and speed of film formation compared to conventional film formation methods. Understood.

Table 1 ■...Epitaxial ○...Good crystal △...Polycrystalline ×...Amorphous Table 2 ◎...Epitaxial ○...Good crystal Table Table 1 Summary of Effects of the Invention] As understood from the above explanations and examples, according to the deposited film forming method of the present invention, the film characteristics and film formation rate of the group III bioconductor thin film to be formed are improved, and Thin films of desired film quality can be formed stably and with good reproducibility, and productivity and mass production of thin films can be easily achieved.

Furthermore, the substrate temperature required to form the deposited film can be lower than that of conventional deposited film formation methods, without adversely affecting film properties. Furthermore, by controlling the excited state of hydrogen atoms and the amount of introduced raw material compounds, film quality can be easily and stably controlled with good reproducibility.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective view of a deposited film forming apparatus suitable for carrying out the present invention, and FIG. 2 is a schematic cross-sectional view of a conventional microwave plasma CVD apparatus. Third
The figure is a diagram showing the relationship between the emission intensity ratio of hydrogen atoms, electrical characteristics, and deposition rate. FIG. 4 is a diagram showing the relationship between the emission intensity ratio of hydrogen atoms and the deposition rate. Regarding FIG. 1, 101...Cylindrical cavity resonator, 10
2...Helscher, 103...Metal mesh, 10
4... Variable cavity length plunger, 105... Hane,
106...Motor, 107...Speed gear, 108
...Rectangular waveguide, 109-E-H tuner, 110
... Throttle, 111... Gas introduction pipe, 112... Gas blowing ring, 113... Gas blowing hole, 11
6... Film forming space, 117... Transport pipe, 118...
Substrate, 119... Substrate boulder - 1120... Gas supply pipe, 121... Boat, 122... Light focusing probe, +23... Quartz fiber, 124... Spare port, 125... Pressure gauge, 126...Continuous wave microwave oscillator, 127...Rectangular waveguide, 128
... Power divider, 129... Rectangular waveguide, 130 Matching device, 131... Aperture. Regarding Fig. 2, 201... rectangular waveguide, 202...
・Microwave introduction window, 203...Plasma generation chamber, 2
04... Film forming chamber, 205,210... Gas supply pipe,
206...Exhaust port, 207...Object to be processed, 208.
... Processing object holder, 209... Metal mesh, 211... Activation space, 212... Activation energy generation means.

Claims (2)

[Claims] (1) A compound (1) containing silicon, which is a raw material for forming a deposited film, and, if necessary, a compound represented by the following general formula (I) in a film forming space for forming a deposited film on the substrate. (2)
and, if necessary, each of the compounds (3) containing an element constituting an element capable of controlling valence electrons in the deposited film is introduced in a gaseous state into the film forming space, and these compounds (1),
Compound (2) and compound (3) are activated in the film-forming space, and at the same time hydrogen atoms in an excited state that chemically react with at least one of these compounds (1), compound (2), and compound (3) are activated. A method for forming a functional deposited film in which hydrogen atoms in an excited state are generated in an activation space different from the film-forming space and are introduced into the film-forming space to form a deposited film on the substrate. , generated by microwave plasma generated in a plasma generation chamber installed in a cavity resonator integrated with two impedance matching circuits in a microwave three-dimensional circuit using hydrogen gas or a mixed gas of hydrogen gas and rare gas. A method for forming a functional deposited film, which further comprises controlling the excited state of generated hydrogen atoms. AaBb………………(I) (However, A indicates an element other than silicon among the elements belonging to Group IV of the periodic table, and B indicates hydrogen (H), halogen (X), hydrocarbon Indicates a group selected from the groups, a indicates a positive integer equal to or an integral multiple of the valence of B, and b indicates a positive integer.) (2) The function according to claim 1, characterized in that one energy divided by a power divider from a microwave power source is input into the film forming chamber, and the other energy is input into the plasma generation chamber. method for forming a deposited film.