JPH06204136A - Thin film forming method and thin film forming equipment and semiconductor element - Google Patents

Abstract

PURPOSE:To improve characteristics and throughput of a thin film element, by a method wherein the region of plasma generated by energy of radiowaves in different frequency bands is separated a small shared region left, a thin film is formed in each region, and a substrate is moved along plasma groups. CONSTITUTION:A material gas group A is introduced into a vacuum vessel A 101 from a gas introducing pipe 108, and the pressures of regions 114, 115 are adjusted to be desired values. An RF power supply 107 whose frequency band is 1-100MHz is turned on, and RF plasma is generated in the region 115. A microwave power supply whose frequency band is 1-100GHz is turned on, and microwaves are introduced into the region 114, thereby generating MW plasma. When both plasmas are stabilized, a substrate is moved in the (a) direction, and thin films are formed on the substrate, in the RF plasma region 115, the shared region 116 and the MW plasma region 114. Thereby element characteristics and throughput of a thin film element are improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thin film forming method and apparatus suitable for manufacturing an element to which a thin film such as a semiconductor thin film, a magnetic thin film, an insulating thin film, a conductive thin film and a superconducting thin film is applied. is there. In particular, a semiconductor element having a semiconductor junction such as a pin junction or a pn junction, for example, a solar cell, a thin film transistor (TFT), a photo sensor, X
The present invention relates to a thin film forming method and apparatus suitable for mass production of line sensors, humidity sensors and the like. In particular, the present invention relates to a technique for continuously forming a thin film on a belt-shaped substrate using a plasma CVD method.

[0002]

2. Description of the Related Art As a technique for forming a thin film, vacuum vapor deposition, MBE, sputtering, ion plating, cluster ion beam vapor deposition, thermal CVD, MO
A CVD method, a plasma CVD method, a photo CVD method, a dipping method, a coating method and the like can be mentioned. However, in order to mass-produce devices using thin films such as semiconductor thin films, magnetic thin films, insulating thin films, and superconducting thin films, it is necessary to have a high deposition rate and excellent device characteristics. As one of such methods, a microwave plasma CVD method (MWPCV
Method D). The MWPCVD method is a method of forming a thin film by introducing a raw material gas into a vacuum container and irradiating the raw material gas group with microwaves to generate plasma, and depositing radicals generated inside the plasma on a substrate. is there. In the MWPCVD method, since the pressure inside the plasma is set to 0.1 to 30 mTorr, the mean free path of the particles is as long as 5 to 30 cm, and the gas phase reaction can be suppressed as much as possible. Therefore, radicals for forming a high quality thin film can be directly flown to the surface of the substrate. Furthermore, since the source gas group can be decomposed by almost 100%, the deposition rate is extremely high.

In order to improve device characteristics, a method of reducing the interface state of a thin film formed on a substrate is as follows.
First, the RF plasma CVD method (RFPCVD
Method) is used to form a super thin film in a state where the deposition rate is relatively low, and then the MWPCVD method is used to form the same thin film in a state where the deposition rate is relatively high.

[0004]

In recent years, it has been desired to simultaneously improve the device characteristics and reduce the cost of thin film devices. In order to reduce the cost, it is necessary to increase the production capacity (throughput), that is, the thin film deposition rate. However, when the throughput is increased by using the MWPCVD method, internal stress, defect level, etc., which occur at the interface with the substrate due to the high deposition rate, often cause problems. That is, since the lattice constant of the substrate and the lattice constant of the thin film are different, a desired thin film of good quality cannot be obtained near the interface. For example, the conductive substrate and the conductive thin film formed thereon are electrically coupled, but there are cases where the desired electrical coupling cannot be formed due to the existence of the interface state. Further, even when a conductive thin film is formed on a substrate having an insulating property, the presence of the interface state may cause a loss of electricity for conducting the thin film in the planar direction. Further, when the magnetic thin film is formed on the insulating substrate, there is a problem that the magnetic thin film cannot obtain a desired coercive force. Further, there is a problem that peeling of the thin film occurs due to internal stress near the interface. On the contrary, as a means for reducing the interface state, MWP
Although there is a method of reducing the deposition rate in the CVD method, the throughput of the thin film element is reduced. Therefore, as a means for reducing the interface state without reducing the throughput, an ultra-thin film is formed on the substrate by using the RFCVD method in a state where the deposition rate is small, and MWPCV is formed on the ultra-thin film.
Forming thin films using the D method has been performed. In the past, the device characteristics and the throughput could be satisfied even by such a method, but at the present time that the device characteristics and the throughput must be further improved, an ultra thin film formed by the RFPCVD method and a thin film formed by the MWPCVD method are used. The interface level and internal stress of the above are problems, and since the process is a batch type, a dramatic improvement in throughput cannot be expected. Further, as a method for dramatically improving the throughput, there is a roll-to-roll method in which a thin film is continuously formed using a strip substrate. This method is used when manufacturing a magnetic tape or the like, and a resin film to be a substrate is wound around a drum in a roll shape, and one end is wound on another drum, while a magnetic thin film is formed on the substrate surface by a vacuum deposition method. Is formed. But such a roll-to-
In order to further increase the throughput in the roll method,
When a thin film is formed by using the MWPCVD method instead of the vacuum evaporation method, the interface state and the internal stress similarly pose a problem. Furthermore, in the roll-to-roll method, RF
Vacuum device and MWP for forming ultra-thin film using PCVD method
Even when a vacuum apparatus for forming a thin film by using CVD is provided, the interface level between the ultra-thin film and the thin film as described above and internal stress become problems, and the entire vacuum apparatus becomes large in size, resulting in a large capital investment. Therefore, it is not possible to expect cost reduction.

When the substrate is composed of the same compound as the thin film, even if the thin film is formed on the substrate by the MWPCVD method, the interface state and internal stress as described above are small. When another thin film is formed on a thin film, the interface level and internal stress at the thin film interface similarly pose problems. The present invention is intended to solve the above problems, specifically, to improve the device characteristics of a thin film element formed by forming a thin film on a substrate than conventional ones, and An object of the present invention is to provide a thin film forming method capable of improving throughput. Further, this is intended to reduce the cost of the thin film element. More specifically, it is an object of the present invention to provide a thin film forming method capable of reducing the interface state with the substrate and the internal stress while improving the throughput. Furthermore, when laminating thin films, it is an object to reduce the interface state and internal stress while improving the throughput.

Further, another object of the present invention is to provide a thin film forming apparatus using the thin film forming method of the present invention.
Further, the cost of the apparatus for manufacturing the thin film element is reduced. Still another object of the present invention is to provide a semiconductor device formed by using the thin film forming method of the present invention. In particular, it is to provide a semiconductor element having a semiconductor junction such as a pin junction or a pn junction.

[0007]

Means for Solving the Problems As a result of intensive investigations by the present inventors in order to achieve the above-mentioned object, the thin film forming method and its apparatus found in the inside of a vacuum container A capable of reducing the pressure inside. One or more source gas group A
In a plasma CVD method for forming a thin film on a substrate by introducing at least two plasmas, and one of the plasma groups has a frequency band of 1 to 10
Plasma (RF plasma) generated by the energy of electromagnetic waves (RF) of 0 MHz, and another one is an electromagnetic wave (microwave) whose frequency band is 1 to 100 GHz.
The plasma (MW plasma) generated by the energy of the RF plasma and the MW plasma are separated from each other in a state where the RF plasma and the MW plasma have a small shared area, and at the same time, each thin film is formed in each plasma area. It is characterized in that the substrate is moved along the plasma group (1).

A desirable mode of the present invention is that the pressure inside the RF plasma is made higher than that of the MW plasma,
A part or all of the raw material gas group A is stored in the vacuum container A with R
The thin film forming method and the apparatus thereof are characterized by flowing from the F plasma region toward the MW plasma region. Furthermore, a desirable mode of the present invention is characterized in that the substrate has a band-like shape and is flexible, and that the thin film is continuously moved in the direction of the substrate during the thin film formation. Is.

Further, according to a preferred embodiment of the present invention, another vacuum container B is connected to the outside of the vacuum container A through a separation passage in which a strip-shaped substrate can move inside, and the cross section of the separation passage is Almost similar to the cross section of the substrate, the shortest distance d between the inner wall of the separation passage and the substrate satisfies the relation that the length L with respect to the moving direction of the strip substrate is L> 50 × d, and in the vacuum container B, It is characterized in that another thin film having a property different from that of the thin film is laminated on the same strip-shaped substrate by using one or plural kinds of raw material gas group B having a raw material gas not included in the raw material gas group A. The thin film forming method and the apparatus thereof.

Further, a desirable mode of the present invention is that the scavenging gas is introduced into the separation passage, and the scavenging gas flows from the separation passage toward the vacuum container A and / or the vacuum container B. A method and an apparatus thereof. Further, in a desirable mode of the present invention, the scavenging gas is an inert gas, a gas constituting the raw material gas group A, and a raw material gas group B.
The thin film forming method and the apparatus thereof are characterized in that the gas is selected from the gases constituting the above.

Further, a desirable mode of the present invention is characterized in that an exhaust port is provided in the separation passage and a part of the raw material gas group A or / and the raw material gas group B is exhausted from the exhaust gas passage. Method and its equipment. Further, a desirable mode of the present invention is the thin film forming method and the apparatus thereof, wherein the strong electric field direction of the microwave introduced into the MW plasma is substantially parallel to the substrate.

The semiconductor element of the present invention is a semiconductor element having a pin junction and / or a pn junction manufactured by using the thin film forming method and apparatus of the present invention. In the thin film forming method of the present invention, the thin film layer is formed on the substrate by using the RFPCVD method in a state where the deposition rate is small, and then the transition layer is formed in the plasma shared region in which both the RFPCVD method and the MWPCVD method are performed. After the formation, the MWPCVD method is used to form a thin film with a high deposition rate. Therefore, the lattice mismatch at the interface with the substrate can be relaxed and the interface state can be reduced. Further, since the internal stress at the interface can be relieved, delamination at the interface can be suppressed. Further, since the deposition rate gradually increases in the plasma sharing region, the transition layer and the interfaces between the two have very few levels, and the internal stress is also relaxed. Moreover, since the substrate surface is first exposed to RF plasma, the damage to the substrate is extremely small.
Moreover, the deterioration of the substrate is extremely small.

Further, in the thin film forming method of the present invention, the thin film layer is formed on the substrate by the MWPCVD method at a high deposition rate, and then the RFPCVD method and the MWPCV method are used.
The transition layer is formed in the plasma sharing region where the D method is performed together, and then the thin film is formed using the RFPCVD method in a state where the deposition rate is low. Therefore, when another thin film is formed on the thin film formed by the RFPCVD method, the lattice mismatch at this interface can be relaxed and the interface state can be reduced.
Further, since the internal stress at the interface can be relaxed,
Delamination at the interface can be suppressed. In addition, since the deposition rate gradually decreases in the plasma sharing region, the transition layer and the interface between the two have very few levels, and the internal stress is also relaxed.

Further, since the MWPCVD method is used in the present invention, a good quality thin film can be formed in a state where the deposition rate is high. That is, in the MWPCVD method, since the pressure at which plasma is generated is as low as 0.5 to 30 mTorr, the mean free path of gas particles can be lengthened to 5 to 30 cm, which is unnecessary in the gas phase. The polymerization reaction can be suppressed, and a good quality film can be formed on the substrate. Further, since radicals can be transported over a long distance, a uniform thin film can be formed on a large-area substrate. Further, the deposition rate is extremely high in the MWPCVD method (100 angstrom / sec or more).
Therefore, the ratio of impurities adhering to the inner wall of the vacuum container being mixed in the thin film formed by sputtering or heat emission is extremely low. In addition, the residual gas floating inside the vacuum container is decomposed, and the ratio of being mixed as an impurity in the thin film is extremely low.

Further, in the present invention, since the raw material gas is decomposed by using the MWPCVD method, the decomposition efficiency is extremely high, reaching 100%. Therefore, the ratio of the raw material gas introduced into the vacuum container being actually used as a thin film is extremely high, and the raw material gas utilization efficiency is 90% by devising such that the whole plasma is covered with the substrate.
% Can be improved. By improving the efficiency of using the raw material gas, it is possible to reduce the manufacturing cost of the thin film and the thin film element. Also MW
Since the PCVD method has an extremely high deposition rate, the process time for forming a thin film can be greatly shortened, and therefore the throughput can be increased and the manufacturing cost of the thin film and the thin film element can be reduced. .

Further, in the present invention, MW plasma and RF
Due to the region shared by the plasma, it is possible to form an excellent transition layer which has never been seen before. Although the detailed mechanism for its formation is unknown, it was confirmed that the deposition rate was intermediate between the deposition rate inside the RF plasma and the deposition rate inside the MW plasma in this region. That is, the decomposition efficiency of the source gas is intermediate between the values inside the MW plasma and inside the RF plasma. In such a state, the plasma potential of the common region is MW.
It is considered that it is higher than the plasma potential of plasma and the plasma potential of RF plasma. Normal MWP
In the CVD method, it is extremely difficult to stably maintain a plasma having such an intermediate decomposition efficiency and a large plasma potential at a pressure of 0.5 to 30 mTorr in order to suppress a gas phase reaction. However, in the present invention, MW
The MW energy is supplied from the direction in which the plasma exists, while the RF energy is supplied from the direction in which the RF plasma exists, and since these directions are opposite to each other when viewed from the common region, the plasma does not interfere. It is absorbed inside. Therefore, the plasma state, which is usually difficult to maintain, can be revealed in the shared region.

The transition layer formed in the plasma in such a state fulfills the function as the transition layer more than ever. That is, as described above, the levels inside the transition layer and both interfaces are extremely small, and the internal stresses inside the transition layer and both interfaces are sufficiently relaxed. Further, in the transition layer, the constituent elements of the thin film formed inside the MW plasma are thermally diffused into the thin film formed inside the RF plasma, and the constituent elements of the thin film formed inside the RF plasma are formed inside the MW plasma. It also prevents thermal diffusion into a thin film. This is because a large plasma potential accelerates the ions in the plasma and gives a large kinetic energy to the forming transition layer, and further promotes the surface reaction of the high energy ions. It is thought that it has become. Therefore, mutual diffusion of the constituent elements of the thin film formed inside the MW plasma and the constituent elements of the thin film formed inside the RF plasma can be prevented. When an element having a large thermal diffusion coefficient is used as a constituent element, it is particularly effective.

Further, in the present invention, since the substrates are moved at the same time while forming the respective thin films in the respective plasma regions, the above effect becomes more remarkable. That is, the present invention not only simply replaces the temporal change with the spatial change, but also involves a spatial thin film formation mechanism (for example, anisotropy in the thin film formation process) that does not normally occur, and the transition layer is superior. It is thought that it will be a thing. Moreover, since the substrate is constantly moving, the throughput is dramatically improved, and it is considered that the cost of thin films and thin film elements can be reduced.

Further, in the present invention, since a plurality of thin films having different properties are formed inside the same vacuum container, it is not necessary to use a plurality of vacuum containers, an exhaust device, and a raw material gas introduction device, and the manufacturing device cost can be reduced. You can Particularly, the cost required for the vacuum container used for producing a high-quality thin film and the above-mentioned device and utility associated therewith is enormous. By reducing the cost of the device, the cost of the thin film and the thin film element can be greatly reduced. Can be planned.

Further, the present invention is particularly effective when laminating thin films having different properties or thin films made of different constituent elements in the same vacuum container. For example, when a photovoltaic element is manufactured by laminating a layer made of amorphous silicon (a-Si) and a layer made of amorphous silicon germanium (a-SiGe), the transition layer formed by the forming method of the present invention is the same as described above. Because it is excellent,
The produced photovoltaic element has excellent element characteristics and has no thin layer advantage. Further, for example, a− having different band gaps
The same effect is obtained in the case of forming a photovoltaic element by stacking Si layers.

The present invention is particularly effective when forming a thin film having a relatively large film thickness. The preferable thickness range of the thin film used in the present invention is 0.1 to 100 μm. Further, in the present invention, two or more plasmas may be generated inside the vacuum container. For example, by moving the substrate in the order of RF plasma, MW plasma, RF plasma, the interface state with the substrate, The interface state between the thin film layer and the layer formed above can be reduced, which is particularly effective when manufacturing a thin film element having a multilayer structure.

In the present invention, the pressure inside the RF plasma is made higher than that of the MW plasma, and the raw material gas group A is used.
By flowing a part or all of the above in the vacuum container A from the RF plasma region toward the MW plasma region,
By effectively using the raw material gas, it is possible to reduce the cost of the manufactured thin film or thin film element. That is, in the RF plasma region, the decomposition efficiency of the raw material gas is about 20% at the maximum, and most of the raw material gas is exhausted without being formed as a thin film. Furthermore, in the MW plasma region, almost 100%
Since the source gas can be decomposed, if the MW plasma is covered with a substrate, the source gas can be used almost 100%. In the present invention, as described above, most of the source gas that has not been decomposed in the RF plasma region can be decomposed in the MW plasma region by flowing from the RF plasma region toward the MW plasma region. Further, by covering the RF plasma region and the MW plasma region with the substrate, the raw material gas can be used more effectively. Further, by making the pressure inside the RF plasma higher than the pressure inside the MW plasma, it is possible to prevent the diffusion of the source gas from the MW plasma region to the RF plasma region. Therefore, a kind of raw material gas (A
l) is flown from the RF plasma region to the MW plasma region,
By flowing another kind of raw material gas (A2) of the raw material gas group only into the MW plasma region, a thin film containing the constituent element CA1 of the raw material gas (Al) is formed in the RF plasma region and CA1 in the MW plasma region. Raw material gas (A2)
It is possible to form a thin film containing the constituent element CA2. Therefore, pn junction, pi junction, ni junction, pin
It is also possible to manufacture the thin film element having the junction inside one vacuum container. It is also possible to form a superlattice structure by repeating lamination of thin films several times. Further, for example, when forming an a-Si: H thin film in both plasma regions, SiH ₄ gas and H ₂ gas are caused to flow from the RF plasma region toward the MW plasma region, and SiH ₄ gas flow rate / H in each plasma region. ₂ a-Si formed in each region by changing the gas flow rate:
The hydrogen content inside the H thin film can be changed. a-S
If the hydrogen content of the i: H thin film is large, the band gap becomes large, so that a thin film element having a heterojunction can be formed inside one vacuum container. Further, since the pressure is high in the RF plasma region, the RF plasma can be maintained in a stable state. Moreover, since the pressure is small in MW plasma, MW plasma with good uniformity can be generated.

Further, in the present invention, the substrate has a strip shape and flexibility and is continuously moved in the longitudinal direction of the substrate during thin film formation, so that the throughput can be dramatically improved. In other words, since the substrate is strip-shaped and flexible, it is possible to form a thin film on the substrate while continuously moving it in the longitudinal direction of the substrate, and a processing speed that is unattainable by the batch method is high. Can be achieved. Further, since the substrate is flexible, the RF plasma and the MW plasma can be covered with the substrate, and the raw material gas utilization efficiency can be further improved. Since the substrate is strip-shaped and flexible, the storage space can be reduced and the transportation and handling can be facilitated by storing the substrate in a rolled state. This is particularly effective when a magnetic tape is manufactured by forming a magnetic thin film on a flexible substrate made of a resin. Further, when a semiconductor thin film is formed on a strip-shaped flexible substrate made of metal to manufacture a solar cell, it is particularly effective.

Further, in the present invention, another vacuum container B is connected to the outside of the vacuum container A through a separation passage through which the strip-shaped substrate can move, and the cross section of the separation passage is substantially the same as the substrate cross section. Similarly, the shortest distance d between the inner wall of the separation passage and the substrate satisfies the relationship of 1 to 10 mm, the length L of the strip substrate in the moving direction is L> 50 × d, and in the vacuum container B, the source gas group A Is formed by stacking another thin film having a property different from that of the thin film on the same strip substrate by using one or more kinds of raw material gas group B having a raw material gas not included in The thin film element to be manufactured can be easily manufactured. Further, since different thin films can be formed simultaneously in the vacuum container A and the vacuum container B, the manufacturing speed of the thin film element is extremely high. RFPC is used as a forming method when forming a thin film in the vacuum container B.
The VD method, the MWPCVD method, the photo CVD method, the thermal CVD method and the like can be mentioned. In addition, since the pn junction, pi junction, ni junction, pin junction and the like in the semiconductor thin film element can be formed by the forming method, solar cells, various sensors, flat panel displays and the like can be used as semiconductor thin film elements in a high throughput state. It can be manufactured. If the shortest distance from the strip-shaped substrate is less than 1 mm, the substrate and the separation passage are brought into contact with each other by a slight vibration, and not only the substrate but also the surface of the formed thin film is damaged. Further, if the shortest distance is larger than 10 mm, it becomes difficult to separate the raw material gas group A and the raw material gas group B, and a desired thin film cannot be formed. Further, by satisfying the relationship of L> 50 × d, it is possible to prevent the interaction of electromagnetic waves introduced into the vacuum container A or B.

Further, in the present invention, a scavenging gas is introduced into the separation passage, and the scavenging gas flows from the separation passage toward the vacuum container A or / and the vacuum container B, so that the raw material gas group introduced into the vacuum container A is supplied. Since mutual diffusion of A and the source gas group B introduced into the vacuum container B can be prevented, good heterojunction, pn junction, and pin junction can be formed. In addition, a good interface can be formed. That is, the shortest distance between the separation passage and the strip substrate is 1 to
Since it is as small as 10 mm, the scavenging gas introduced from the separation passage can be made into a viscous flow inside the separation passage, and part of the scavenging gas flows into the vacuum container A and the other flows into the vacuum container B, so that the raw material gas It is possible to prevent the group A from diffusing into the vacuum container B through the separation passage and the source gas group B from diffusing into the vacuum container A through the separation passage. As another form, the book film forming method of the present invention may be carried out in a state where almost all the scavenging gas flows into the vacuum container A. In this case, since the raw material gas group B also flows into the vacuum container A, in the present embodiment, it is desirable that the raw material gas group B is composed of a gas of the type included in the raw material gas group A. Similarly, the thin film forming method of the present invention may be carried out with almost all the scavenging gas flowing into the vacuum container B. In this case, since the raw material gas group A also flows into the vacuum container B, in the present embodiment, the raw material gas group A is preferably composed of a gas of the type included in the raw material gas group B.

Further, in the present invention, the scavenging gas is a gas selected from an inert gas, a gas forming the raw material gas group A, and a gas forming the raw material gas group B. The thin film formed in 1) is excellent in that it has extremely few unnecessary impurities, and the manufactured thin film element has excellent element characteristics. Further, in the present invention, an exhaust port is provided in the separation passage, and the raw material gas group A or /
Since part of the raw material gas group B is exhausted, part of the raw material gas B diffuses inside the vacuum container A or part of the raw material gas A diffuses inside the vacuum container B as in the above. Can be prevented. That is, since the gas is in a viscous flow state inside the separation passage, it is considered that the above mutual diffusion does not occur. Therefore, since it is possible to form a good bond or a good interface,
The device characteristics of the thin film device are extremely high.

Further, in the present invention, since the strong electric field direction of the microwave introduced into the MW plasma is substantially parallel to the substrate, the substrate or the substrate on which the thin film is formed is not directly heated by the microwave and the thin film Since the substrate temperature does not rise sharply during formation, a good book film can be stably supplied. It is particularly effective when the magnetic thin film is formed at a low temperature. Further, when the substrate is made of a material that absorbs microwaves, the microwaves do not cause deformation or alteration of the substrate. Therefore, the selection range of the substrate is widened, and an inexpensive material such as a resin film or a metal film can be used.

The semiconductor thin film element of the present invention is a semiconductor element having a pin junction and / or a pn junction manufactured by using the above-described thin film forming method and apparatus, and unnecessary impurities contained in the thin film are extremely large. In addition, it has a small number of good interfaces with few interface states. Further, the semiconductor thin film element of the present invention is manufactured at a high throughput, so that the cost is reduced.

The thin film formed in the present invention is a semiconductor thin film, a magnetic thin film, an insulating book film, a conductive book film, a superconducting thin film, etc., and the thin film element manufactured in the present invention has these thin films on a substrate. Or formed by laminating a plurality of thin films. In particular, the present invention is effective when a large number of semiconductor devices having a semiconductor junction such as a pin junction and a pn junction, for example, a solar cell, a thin film transistor TFT, a photo sensor, an X-ray sensor and a humidity sensor are produced. It is also effective when mass-producing magnetic tape and the like. Furthermore, it is particularly effective when the thin film is continuously formed on the strip substrate by using the plasma CVD method.

The thin film forming method and apparatus of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a schematic view of a thin film forming apparatus capable of carrying out the thin film forming method of the present invention, which comprises basic constituent elements. First, 101 in the figure is a vacuum container A capable of reducing the pressure inside, and an exhaust port 102.
More internal gas can be exhausted. Reference numeral 103 denotes a substrate, which can be moved in the direction of arrow a in the figure. 10
4, 105 are cassettes for sending and storing the substrates,
This is for forming thin films on many substrates in one thin film forming process. An RF electrode 106 has a flat plate shape. 107 is an RF power supply. Reference numeral 108 is an inlet pipe for the raw material gas group A, and 109 is a conductance valve for adjusting the pressure inside the vacuum container A, which is attached to the exhaust port 102. Reference numeral 110 denotes a microwave introduction window, which is made of a dielectric (for example, quartz, alumina ceramics, or boron nitride) capable of introducing microwaves into the vacuum container and separating atmospheric pressure and vacuum. An applicator 112 expands the microwave propagated from the waveguide 113 and expands the MW plasma region 114. R
The region 115 of the F plasma extends into the space between the RF electrode and the substrate, and the shared region 116 of the RF plasma and the MW plasma.
Is a region smaller than the RF plasma region and the MW plasma region. Reference numeral 117 is a partition for adjusting the flow of the raw material gas group. Reference numeral 118 is a heater (halogen heater) for heating the substrate.

The outline of the method of using this thin film forming apparatus will be described below. First, the cassette 104 in which the substrate is stored and the cassette 105 for storing the substrate are set inside the apparatus leaking to the atmosphere. Next, the inside is evacuated using a vacuum exhaust pump (not shown), and when the exhaust is sufficiently exhausted, the heater is turned on, the raw material gas group A is introduced into the vacuum container A from 108, and the conductance valve 109 is adjusted to adjust the area. The pressures of 114 and 115 are set to desired pressures. Next, turn on the RF power and turn R on the area 115.
Produces F plasma. Next, a microwave power source (not shown) is turned on to introduce microwaves into the region 114 through a waveguide, an applicator and a microwave introduction window to generate MW plasma. When both plasmas are stable, the substrate is moved in the direction of arrow a so that the RF plasma region 1 is formed on the substrate.
After forming the respective thin films in 15, the common region 116 and the MW plasma region 114, the substrates are successively stored in the storage cassette. When thin films have been formed on all substrates, turn off the RF power and MW power and turn off the RF plasma and M
The W plasma is extinguished, the introduction of the raw material gas group A is stopped, and when the inside of the vacuum container A is sufficiently evacuated, the vacuum container A is leaked to the atmosphere, the substrate storage cassette is taken out, and the thin film forming process is completed.

The preferred range of thin film forming conditions will be described below. Each forming condition depends on the type of the thin film and the substrate to be formed, but an approximate range will be shown.
First, the substrate temperature is preferably in the range of 20 to 700 ° C. The source gas flow rate is 50 to 10000 sccm, and the pressure is preferably 0.05 to 5 Torr in the RF plasma region and 0.1 to 30 mTorr in the MW plasma region. The MW power to be introduced is preferably in the range of 50 to 1000W. Further, the moving speed of the substrate is preferably in the range of 1 to 100 cm / min.

In some cases, a metal bias rod may be installed in the MW plasma region and DC power may be applied to adjust the plasma potential. In this case, the voltage can be raised to the voltage at which spark discharge begins,
Usually, about -300 to 300 V is a preferable range. a
When forming an amorphous silicon thin film such as -Si: H, about 30 to 250 V is preferable. Further, RF power may be applied to the bias rod to adjust the plasma potential. In this case, the electric power can be increased up to the electric power at which the Sverk discharge starts to occur, but a range of 0 to 2000 W is usually a preferable range. When forming an amorphous silicon-based thin film such as a-Si: H, it is preferably about 100 to 1000 W. Furthermore, DC power and RF power may be applied simultaneously.

In the thin film forming method of the present invention, more thin films may be formed inside the vacuum container A by using two or more plasmas. For example, one more RF plasma may be generated inside the vacuum container A201 in FIG. 2 and may have a region shared with the MW plasma as in FIG. Therefore, it is possible to form a thin film in which the interface state with the substrate and the interface state on the surface side are reduced. 2 in FIG.
Plasma other than one plasma may be generated inside the vacuum container A in a state where there is no shared region to form another thin film. Further, a thin film forming method such as a vacuum vapor deposition method, a sputtering method, an ion implantation method, a MOCVD method, a thermal diffusion method, a photo CVD method, and a cluster ion beam method can be carried out inside the vacuum container A so that another thin film is formed. May be formed.

The semiconductor thin film formed in the present invention includes crystalline, polycrystalline, microcrystalline, and amorphous Ge and S.
i, Se, SiGe, AlSi, SiSn, SiPb,
GaAs, GaAlAs, ZnSe, ZnTe, Zn
S, CdS, CdSe, CdTe, AlP, AlAs,
AlSb, GaN, GaP, GaSb, InN, In
P, InAS, InSb, GeC, GeSn, SnC,
CuInSe ₂ or the like may be used, and a conductive type may be controlled by containing a doping agent. Further, H and halogen (X) may be bonded, and elements such as C, O and N may be contained.

The magnetic thin film formed in the present invention is FeN in a crystalline, polycrystalline, microcrystalline or amorphous state.
i, FeNiCo, PdNi, MnBi, MnCuB
i, TbFeO ³ , GdCo, GdFe, GdTbF
e, NdFe, TbFe, CoCrTaPt, CoP
t, CoPd, SmFeO ₃ , GdFeO ^{3 and the} like. Further, elements such as C, O and N may be contained.

Examples of the insulating thin film formed in the present invention include carbon compounds, oxygen compounds, nitrogen compounds and fluorine compounds, and crystalline, polycrystalline, microcrystalline and amorphous states are used. Carbon compounds include C and B ₄
C, HfC, MoC ₃ , NbC, SiC, TaC, Ti
C, VC, WC, ZrC and the like can be mentioned. Examples of oxygen compounds include Li ₂ O, LiNbO ₃ , LiTaO ₃ , and Be.
O, MgO, Al ₂ O ₃ , SiO ₂ , KNbO ₃ , CaO,
TiO, TiO ₂ , Ti ₂ O ₃ , BaTiO ₃ , SrTiO
₃ , CaTiO ₃ , Bi ₂ TiO ₅ , PbTiO ₃ , V
₂ O ₅ , Cr ₂ O ₃ , MnO ₂ , FeO, Fe ₂ O ₃ , Fe ₃ O
₄ , CoO, NiO, CuO, ZnO, Ga ₂ O ₃ , Sr
ZrO ₃ , GeO ₂ , Y ₂ O ₃ , YAlO ₃ , ZrO, Zr
O ₂ , Nb ₂ O ₅ , MoO ₃ , CdO, Cd ₂ SnO ₄ , In
₂ O ₃ , SnO ₂ , Sb ₂ O ₃ , La ₂ O ₃ , LaAlO ₃ , L
aGaO ₃ , HfO ₂ , Ta ₂ O ₅ , CeO ₂ , Nd ₂ O ₃ ,
NdGaO ₃ , Sm ₂ O ₃ , Dy ₂ O ₃ , Ho ₂ O ₃ , Eu ₂ O
₃ , Gd ₂ O ₃ , Er ₂ O ₃ , WO ₃ , IrO, PbO, Pb
ZrO ₃ , Bi ₂ O _{3 and the} like can be mentioned. As the nitrogen compound, BN, AlN, HfN, NbN, SiN, Si
₃ N ₄ , TaN, TiN, VN, ZrN and the like can be mentioned.
Examples of the fluorine compound include AlF ₃ , BaF ₂ , BiF ₃ ,
_{CaF 2, CeF 3, DyF 3} , ErF 3, EuF 3, Gd
F ₃ , HoF ₃ , LaF ₃ , LiF, MgF ₂ , NaF, N
_{dF 3, PbF 2, PrF 3} , SrF 2, TbF 3, YF 3 , and the like.

The conductive thin film formed in the present invention includes oxygen compounds, metals and their alloys, and those in the crystalline, polycrystalline, microcrystalline or amorphous state are used.
As the oxygen compound, SnO ₂ , In ₂ O ₃ , ITO, Zn
O, TiO ₂ , CdO, Cd ₂ SnO ₄ , Bi ₂ O ₃ , Mo
Examples include O ₃ and Na _x WO ₃ . As the metal, Ag,
Al, Au, Bi, Cd, Ce, Co, Cr, Cu, D
y, Er, Eu, Fe, Ga, Gd, Hf, Ho, I
n, Ir, La, Lu, Mg, Mn, Mo, Nb, N
d, Ni, Pb, Pd, Pr, Pt, Sb, Sc, S
m, Sn, Ta, Tb, Te, Ti, Tm, V, W,
Examples thereof include Y, Yb, Zn, Zr, etc., and alloys thereof may be used.

The superconducting thin film formed in the present invention is YB in a crystalline, polycrystalline, microcrystalline or amorphous state.
aCuO, BiPbSrCaCuO, BiSrCaCu
O, LaSrCaCuO, BiSrVO, TlSrCa
CuO etc. are mentioned. The thin film formed in the present invention is composed of the above-mentioned elements or compounds, but may be a mixture or mixed crystal of these elements, and may be one in which the component ratio of the constituent elements changes in the film thickness direction and the plane direction. Good. Further, in the present invention, a thin film element can be manufactured by laminating a large number of these thin films.

The substrate used in the present invention may be composed of a single body, or may be a single or a plurality of the above-mentioned thin films formed on a support. NiCr, stainless, A
1, Cr, Mo, Au, Nb, Ta, V, Ti, Pt,
Examples include metals such as Pb, Sn, and Fe, or alloys thereof. In order to use these materials as a support, it is desirable that the material has a sheet shape or a roll shape in which a belt-shaped sheet is wound around a cylindrical body. Examples of the insulating single substrate material include synthetic resins such as polyester, polyethylene, polycarbonate, cellulose acetate, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene and polyamide, or glass, ceramics, paper and the like. In order to use these materials as a support, it is desirable that the material has a sheet shape or a roll shape in which a belt-shaped sheet is wound around a cylindrical body.

When a thin film is formed on a support to form a substrate, the thin film is formed by a vacuum deposition method, a sputtering method, a screen printing method, a dipping method, the deposited film forming method of the present invention, or the like. The surface shape of the support is smooth or, if necessary, the height of the peak is up to 0. l ~
There may be unevenness of 1.0 μm. When flexibility is required, the thickness of the substrate can be made as thin as possible within the range where the function as a support is sufficiently exerted. However, it is usually 10 μm or more in terms of mechanical strength and the like in terms of manufacturing and handling of the support.

The raw material gas used in the present invention is preferably a gas containing the constituent elements of the desired thin film at room temperature and atmospheric pressure, but may be a liquid or solid having a large vapor pressure at room temperature. In the case of a liquid, bubbling with another gas may transport the desired raw material gas from the cylinder to the vacuum container. Further, as a raw material gas, H ₂ , N ₂ , O ₂ , He, Ar, Ne, Xe, etc. may be introduced into the vacuum container together with the gas containing the constituent elements of the thin film.

[0043]

EXAMPLES Amorphous silicon (a-Si: H), Z
nO, a thin film such as amorphous silicon nitride (a-SiN),
Although the thin film forming method of the present invention will be described in detail by manufacturing and manufacturing a book film element such as a solar cell and a TFT, the present invention is not limited thereto.

Example 1 Using the thin film forming apparatus shown in FIG.
An a-Si: H thin film, which is a semiconductor thin film, was formed. First 3
0x30 cm², 20 glass substrates with a thickness of 1 mm,
A cassette for ultrasonic cleaning with Seton and IPA and sending
Store in 104, set in vacuum container A,
An empty cassette 105 for delivery was also set. Conda
Vacuum pump, not shown
The pressure inside the vacuum container A is 1 × 10 ^-FiveUntil it becomes Torr
Evacuate with a vacuum and then heat the substrate to 300 ° C.
Set the starter. Gas conduction at stable substrate temperature
SiH4 gas from the inlet tube to 100 sccm, H₂Gas 3
Introduce 00sccm and close the conductance valve a little
Supply of RF power (300W) from the RF power supply to the RF electrode
Then, RF plasma was generated. Furthermore, MW not shown
MW power (500
W) was supplied to generate MW plasma. At this time
Adjust the conductance valve to adjust the inside of the RF plasma.
Pressure is 0.5 Torr, pressure inside MW plasma is 5 m
It was set to Torr. And then the reflected power of F power
Matching box not shown to minimize force
Adjust the LC circuit of the
The tuner (not shown) was adjusted so as to reduce the number. Plastic
When the Zuma is stable, remove the board from the cassette 104.
RF plasma area and MW plasma at a moving speed of 0 cm / min
And the plasma is moved in two plasma regions.
A cassette 105 for storing a substrate while forming an i: H thin film
I put them in one after another. A-Si on all substrates:
After forming the H thin film, MW power supply and RF power
Turn off the source and heater, extinguish the plasma, raw material gas group
The supply of A was also stopped. Vacuum container with vacuum pump (not shown)
The pressure of A is 1 × 10^-FiveEvacuate to Torr,
When the substrate temperature has dropped to room temperature, vacuum chamber A is read.
I'm sorry. The substrate stored in the cassette 105 was taken out.
However, it was found that a thin film of a-Si: H was formed.
won.

<Comparative Example l> An a-Si: H thin film was formed without the shared region 116. An a-Si: H thin film was formed on the glass substrate in the same manner as in Example 1 except that the RF electrode was moved to the left in the figure to separate the RF plasma and the MW plasma and to eliminate the shared region. <Evaluation 1> When the formed a-Si: H thin film was observed with an optical microscope, it was found that the thin film of Comparative Example 1 was slightly delaminated from the end. When the film thickness distribution was measured using a contact needle type film thickness meter, it was found that the film thickness at the edges was about 90% of the film thickness at the center of the substrate in both cases. When the band gap of the thin film without delamination was measured with a spectrophotometer, the average band gaps of the thin films of Example 1 and Comparative Example 1 were both 1.75 (eV). Next, on the a-Si: H thin film, a Cr film having a thickness of 0.2 μm was formed.
A pair of comb-shaped electrodes consisting of was formed by a vacuum deposition method, and the conductivity was measured. First, 1.0V to the electrode in the dark pox
Was applied and the dark conductivity (σd) was measured. Similarly, Xe
The photoconductivity (σp) was measured using pseudo sunlight (solar simulator, 100 mW / cm ² , spectrum AM1.5) using a lamp as a light source. As a result of the measurement, the dark conductivity of Example 1 is smaller (σdj <σdh), and the photoconductivity of Example 1 is larger (σpj> σp).
h), the ratio (R: σp / σd) was much larger in Example 1 (Rj >> Rh). Further, the level density from the valence band of a-Si: H was measured using the constant photocurrent method (CPM), and it was found that Example 1 had a much lower level density.

From the above evaluation, it was found that the thin film forming method of the present invention is superior to the conventional thin film forming method.
In addition, the time required to form a thin film having a film thickness of 1.0 (center of the substrate) μm on the substrate was substantially 25 minutes, and the thin film forming process was completed at a high process processing rate which has never been obtained. Example 2 A ZnO thin film which is a conductive thin film was formed using the thin film forming apparatus shown in FIG. The ZnO thin film is used as a transparent electrode. Ten glass substrates the same as those used in Example 1 and ten stainless steel substrates whose both surfaces were mirror-polished were ultrasonically cleaned with acetone and IPA, and a ZnO film was formed in the same procedure as in Example 1. 1.0 μm was formed. The formation conditions at that time were as follows: the substrate temperature was 150 ° C., (CH3) ₂ Zn was 100 sccm from the heated liquid cylinder,
50 sccm of O ₂ gas is introduced, RF power is 400 W,
MW power is 600W, pressure inside RF plasma is 1.0
Torr, the pressure inside the MW plasma is 10 mTorr,
The moving speed of the substrate was 30 cm / min. Cassette 105
When the substrate stored in was taken out, it was found that a ZnO thin film was formed.

<Comparative Example 2> Similar to Comparative Example 1, a ZnO thin film was formed without a shared region. Move the RF electrode to the left in the figure to separate RF plasma and MW plasma,
A ZnO thin film was formed on a glass and stainless steel substrate in the same manner as in Example 2 except that the common region was eliminated.

<Evaluation 2> When the formed ZnO thin film was observed with an optical microscope, it was found that the thin film of Comparative Example 1 was slightly delaminated from the edges. When the film thickness distribution of the ZnO thin film formed on the glass substrate was measured using a contact needle type film thickness meter, it was found that the film thickness at the edges was about 92% of the film thickness at the center of the substrate. Do you get it. Further, when the band gap of the ZnO thin film on the glass substrate without delamination was measured using a spectrophotometer, the average band gaps of the ZnO thin films of Example 2 and Comparative Example 2 were both 3.2 (eV). there were. Next, on the ZnO thin film formed on the stainless steel substrate, a C film having a thickness of 0.2 μm and a diameter of 2 mm was formed.
A counter electrode made of r was formed by a vacuum vapor deposition method, 0.01 V was applied between the stainless substrate and the counter electrode, and the dark conductivity (σd) was measured. As a result of the measurement, the dark conductivity is found in Example 2.
Was found to be larger (σdj <σdh). From the above results, it was found that the thin film of Example 2 was superior as the conductive thin film and the transparent electrode.

From the above evaluation, it was found that the thin film forming method of the present invention is superior to the conventional thin film forming method.
In addition, the time required to form a thin film having a film thickness of about 1.0 (center of the substrate) μm on the substrate was substantially 25 minutes, and the thin film forming process was completed at a high process processing speed which has never been obtained. Example 3 An a-SiN: H thin film, which is an insulating thin film, was formed using the thin film forming apparatus shown in FIG. First, 20 glass substrates the same as in Example 2 were ultrasonically cleaned with acetone and IPA, and an a-SiN: H thin film was formed on the substrate in the same manner as in Example 1. As the formation conditions, the substrate temperature is 200 ° C., SiH 4 gas is introduced at 100 sccm and NH ₃ gas is introduced at 100 sccm from the gas introduction pipe, RF power is set to 300 W, and MW is set to MW.
Electric power is 500W, pressure inside RF plasma is 0.7To
The pressure inside the rr and MW plasma was set to 7 mTorr, and the moving speed of the substrate was set to 50 cm / min. When the substrate stored in the cassette 105 is taken out, a-S
It was found that a thin film of iN: H was formed.

Comparative Example 3 An a-SiN: H thin film was formed without the shared region 116. An a-SiN: H thin film was formed on the glass substrate in the same manner as in Example 3 except that the RF electrode was moved to the left in the figure to separate the RF plasma and the MW plasma and to eliminate the shared region.

<Evaluation 3> When the formed a-Si: H thin film was observed with an optical microscope, it was found that the thin film of Comparative Example 1 was slightly delaminated from the edges. When the film thickness distribution was measured using a contact needle type film thickness meter, it was found that the film thickness at the edges was about 90% of the film thickness at the center of the substrate in both cases. Next, a comb-shaped electrode similar to that in Example 1 was formed by a vacuum vapor deposition method, and dark conductivity (σd) was measured. When AC5V (100 kHz) was applied between the electrodes in the dark box to determine the dark conductivity (σd), Example 3 was obtained.
It was found that the above was smaller (σdj <σdh), and it was found that it was excellent as an insulating book film.

From the above evaluation, it was found that the thin film forming method of the present invention is superior to the conventional thin film forming method.
In addition, the time required to form a thin film having a film thickness of 1.0 (center of the substrate) μm on the substrate was substantially 15 minutes, and the thin film forming process was completed at a high process processing speed which has never been obtained in the past. Example 4 A solar cell was manufactured using the thin film element manufacturing apparatus shown in FIG. The device comprises a strip-shaped and flexible substrate 20.
7 in the form of a roll, and while moving from the delivery roll 208 toward the winding roll 209, the vacuum container A20
1, inside the vacuum container B202 and the vacuum container C203, thin films having different properties are simultaneously formed. Three plasmas are generated inside the vacuum container A, and two RF plasmas 205 are separated from one MW plasma 204 so that a shared region 206 is slightly left.
Further, a bias rod 220 was provided at the center of the MW plasma perpendicular to the paper surface so that DC power could be applied.
The RFPCVD method can be performed in the vacuum containers B and C. Also, vacuum container D210, vacuum container E
Reference numeral 211 is for accommodating a sending roll and a winding roll, respectively. These vacuum vessels are arranged as shown in the figure, and each vacuum vessel is connected by a separation passage 212. The shortest distance d between the separation passage and the strip substrate is 5
mm, and the length L in the moving direction of the substrate was 300 mm so that L> 50 × d was satisfied. An introduction pipe 213 for introducing scavenging gas is connected to each separation passage,
The scavenging gas flows toward each vacuum container and is exhausted from each exhaust port together with the raw material gas group.

FIG. 3 shows a solar cell 301 manufactured by using the apparatus, in which a reflective layer 303 made of Ag is provided on a belt-shaped support 302, a transparent conductive layer 304 made of ZnO is provided thereon, and a-Si is provided thereon. : H: P n layer 306, a-Si: H i layer 307 formed thereon, and a-Si formed thereon
A p-layer 308 made of C: H: B and ITO (In
2O3, SnO2) and a comb-shaped collector electrode 310 made of Ag are laminated on the transparent electrode 309. In the device of FIG. 2, the n layer, i layer, and p layer, which are the most important layers that influence the element characteristics of the solar cell, are formed, and as the substrate 305, the Ag reflective layer and the ZnO transparent layer are formed on the support 302. The one in which the conductive layer was formed was used.

The procedure for manufacturing the solar cell of FIG. 3 using the apparatus of FIG. 2 will be described in detail below. First, a substrate was manufactured. Mirror-polished on both sides, 30 cm x 300 m, thickness 0.
A 1 mm band-shaped stainless steel substrate was ultrasonically cleaned with acetone and IPA and wound on a drum having a diameter of 30 cm. next,
An Ag reflective layer having a layer thickness of 0.3 μm and a ZnO transparent conductive layer having a layer thickness of 2.0 μm were formed on one surface by a sputtering method to complete the production of the substrate.

The delivery roll around which the substrate is wound is set inside the vacuum container 210, and the end of the substrate is wound onto the winding roll through each separation passage and each vacuum container. After the board is set, each conductance valve 21
4 is fully opened, and the pressure inside the vacuum container and the separation passage is adjusted to 1 × 10 by a vacuum exhaust pump connected to each vacuum container.
-Evacuate to ^-4 Torr. Next, each heater 2
15 is set so that the substrate temperature becomes a predetermined temperature, and when the substrate temperature is stable, the substrate is moved in the direction of the arrow at a speed of 1 m / min to introduce the raw material gas connected to the vacuum containers A, B, and C. A predetermined source gas group is introduced from the pipe 216. In the vacuum container A, the flow of the raw material gas was devised so as to change from RF plasma to MW plasma. Further, 100 sccm of H ₂ gas was introduced as a scavenging gas from each scavenging gas introducing pipe. Next, in the same manner as in Example 1, RF plasma and MW plasma are generated in each vacuum container, and each conductance valve is adjusted so that the pressure inside each plasma becomes a predetermined pressure. In the vacuum container A, the i layer,
In the vacuum container C, the p layer was formed. When the winding of the substrate is completed, the RF plasma and MW plasma are extinguished,
The introduction of the raw material gas group was stopped and the heater was turned off. When the substrate had cooled to room temperature, the introduction of scavenging gas was stopped, the entire apparatus was leaked, and the winding port was taken out. n layers,
The conditions for forming the i layer and the p layer are collectively shown in Table 1.

[0056]

[Table 1]

Next, a transparent electrode made of ITO was formed on the p layer by a vacuum vapor deposition method, further cut into a size of 15 × 15 cm ² , and a comb-shaped collector electrode made of Ag was vacuum deposited on the transparent electrode. Then, the production of the solar cell was completed. <Comparative Example 4> A solar cell was manufactured by forming an i layer in a state where the shared regions 205 and 206 were not present. A solar cell was manufactured in the same manner as in Example 4 except that the RF electrode was moved in a direction away from the applicator to separate the two RF plasmas and the MW plasma and the shared region was extinguished.

<Evaluation 4> Twenty manufactured solar cells were randomly selected and evaluated. Observation with an optical microscope revealed that in the thin film of Comparative Example 4, delamination was slightly generated from the edges. Next, the same solar simulator as in Example 1 (100 mW / cm ² , spectrum A
The photoelectric conversion efficiency (η) was measured using M1.5). The measurement is obtained by applying a voltage between the collecting electrode and the substrate and tracing the VI curve. As a result, the photoelectric conversion efficiency was higher in Example 4 (ηj> η).
h). This is due in part to the fact that the elements are slightly short-circuited in the solar cell of Comparative Example 4 because the layers are separated at the ends. Further, when a solar cell that was not short-circuited was extracted and the average photoelectric conversion efficiency (ηa) was obtained, Example 4 was also higher (ηaj> ηah). This is p
It is considered that this is because the interface states at the i interface and the ni interface decreased. Further, the level density of the i layer of the non-short-circuited solar cell was measured using the constant photocurrent method (CPM) as in Example 1, and it was found that Example 4 was much smaller.

From the above evaluation, it was found that the thin film forming method of the present invention is superior to the conventional thin film forming method.
Further, when the amount of thin film element produced per minute was converted into electric power generated, it was 21 W / min, and the thin film element could be produced at a high production rate which has never been obtained. Example 5 The scavenging gas introduction pipe connected to each separation passage of the apparatus of FIG. 2 was removed, and an exhaust port was connected instead. A solar cell was manufactured in the same manner as in Example 4 except that a part of the raw material gas group was exhausted from the exhaust port instead of introducing the scavenging gas in Example 4 so that each raw material gas group did not mutually diffuse. .

<Evaluation 5> 20 solar cells produced in the same manner as in Evaluation 4 were randomly selected and evaluated. When observed with an optical microscope, delamination did not occur. Next, when the photoelectric conversion efficiency (η) was measured in the same manner as in Example 4, the photoelectric conversion efficiency was almost the same. There were no short-circuited solar cells.

From the above evaluation, it was found that the thin film forming method of the present invention is superior to the conventional thin film forming method.
Further, when the amount of the thin film element produced per 1 minute was converted into electric power generated, it was 20 W / min, and the thin film element could be produced at a high production rate which has never been obtained. Example 6 A solar cell was manufactured such that the strong electric field direction of the microwave introduced into the MW plasma was parallel to the substrate. In the device shown in FIG. 2, the direction of microwaves was changed from the front side to the back side of the paper, and the mounting angle of the waveguide was adjusted so that the strong electric field direction was parallel to the substrate. A battery was manufactured.

<Evaluation 6> 20 solar cells manufactured in the same manner as in Evaluation 4 were randomly selected and evaluated. When observed with an optical microscope, delamination did not occur. Next, when the photoelectric conversion efficiency (η) was measured in the same manner as in Example 4, the photoelectric conversion efficiency in Example 6 was better. When the CPM was measured in the same manner as in Example 4 and the level density was determined, a result slightly smaller than that in Example 4 was obtained. There was no short-circuited solar cell.

Example 7 A solar cell was manufactured by introducing the gas constituting the raw material gas A into the separation passage. A solar cell was manufactured in the same manner as in Example 4 except that SiH4 gas was introduced at 50 sccm from each introduction tube as the scavenging gas to be introduced. <Evaluation 7> Twenty solar cells manufactured in the same manner as in Evaluation 4 were randomly selected and evaluated. When observed with an optical microscope, delamination did not occur. Next, when the photoelectric conversion efficiency (η) was measured in the same manner as in Example 4, the photoelectric conversion efficiency was almost the same. There was no short-circuited solar cell.

Example 8 A liquid crystal driving panel for a flat panel display shown in FIG. 5 was manufactured using the thin film element manufacturing apparatus shown in FIG. The panel of FIG. 5 is 30 × 20c
The substrate of m ² has 600 × 400 pixels. The apparatus of FIG. 4 is obtained by connecting three vacuum containers A of the apparatus of FIG. 2 to the thin film forming method of the present invention,
It can be carried out in B and C. Substrates can be sent and stored in the vacuum vessels D and E, and a gate valve 420 is provided between the separation passage and the vacuum vessels D and E.
It is a load lock type. These vacuum vessels are shown in FIG.
Connected via a separation passage similar to
Can move inside these vacuum vessels and separation passages as shown. The basic usage is the same as that of the apparatus of FIGS. 1 and 2, but since the vacuum vessels D and E are of the load lock type, the vacuum vessels A, B, and C are depressurized, and the vacuum vessels are Leaking D and E, it is possible to set and take out the substrate.

FIGS. 6A to 6C sequentially explain the steps for forming the TFT portion of FIG. 5, and show the sectional shape of the TFT portion.
The outline of the process is as follows. (A) A gate electrode is formed on a substrate and formed into a trapezoid by a photolithography process. (B) A gate insulating layer, using the thin film forming method of the present invention,
An i layer and an n layer are formed. (C) i layer other than the TFT portion, n by photolithography process
Remove the layer. (D) A transparent electrode is formed on the gate insulating layer. (E) Form source / drain electrodes. (F) The source / drain electrodes are separated by a photolithography process, and the n layer is also separated. (G) Forming a protective layer First, a glass substrate having a size of 30 × 20 cm ² and a thickness of 1.0 mm is ultrasonically cleaned with acetone and IPA, and a gate electrode having a film thickness of 50 nm made of a Mo—Ta alloy is formed by a sputtering method. , A photolithography process and a dry etching (DE) process were used to perform trapezoidal patterning as shown in the figure. On this occasion,
CF4 / O2 gas is used as the etching gas, and a trapezoidal shape can be formed by changing the flow rate ratio with time. This completes the production of the substrate.

Next, the step (b) was carried out using the apparatus shown in FIG. The details will be described below. Gate valve 4 in advance
The valves 20, 421 are closed, and the vacuum vessels A, B, C are in a depressurized state. First, 100 substrates each having a gate electrode formed thereon were set in a vacuum container D with the surface on which the gate electrode was formed facing down. Next, the vacuum containers D and E are evacuated by a vacuum exhaust pump (not shown) to a pressure of 1 × 10.
^{At -5} Torr, the gate valves 420 and 421 were opened and the heater was set. When the substrate temperature became stable at a predetermined concentration, He gas as a scavenging gas was caused to flow through each separation passage, and a raw material gas group was introduced into each vacuum container. Next, in the same manner as in Example 4, RF plasma and MW plasma were generated inside each vacuum vessel, and the substrate was moved at a speed of 70 cm
Moved in / min. In the vacuum container A, a gate insulating layer made of a-SiN and having a layer thickness of 400 nm is used. In the vacuum container B, a-
An i layer (active layer) made of Si: H having a layer thickness of 80 nm and an n layer (contact layer) made of a-Si: H: P having a layer thickness of 40 nm were formed in the vacuum container C. The formation conditions are summarized in Table 2.

[0067]

[Table 2]

Next, the i layer and the n layer were patterned as shown in FIG. 6- (c) by using a photolithography process and a wet etching process. HF to HN for wet etching process
An etchant consisting of O ₃ + CH ₃ COOH was used. Next, using a sputtering method, the layer thickness of ITO is 50 n
m transparent electrode was formed and patterned as shown in FIG. 6- (d) using a photolithography process and a wet etching process.

Next, a source / drain electrode having a layer thickness of 4000 Å made of Al is formed by using a vacuum evaporation method, and is patterned as shown in FIG. 6- (f) using a photolithography process and a wet etching process. The source electrode and the drain electrode were separated, and the n layer (contact layer) was also separated. The etchant of the source and drain electrodes using H3 PO4 + HNO _3, as an etchant of the n-layer using _{HF + HNO 3 + CH 3 COOH} .

Next, as shown in FIG. 6- (g), a-SiN:
A protective layer made of H and having a layer thickness of 400 angstrom was formed by the apparatus shown in FIG. Gate bus line using photolithography process and dry etching process,
A contact hole leading to the source bus line was opened.
BCl ₃ + Cl ₂ gas was used as the etching gas.

This completes the manufacture of the liquid crystal drive panel. <Comparative Example 8> Similar to Comparative Example 1, all RF plasmas were isolated from the MW plasma, and the gate insulative layer, i layer, and n layer were formed without the shared region 406. A liquid crystal drive panel was manufactured in the same manner as in Example 8 except that plasma was isolated.

<Evaluation 8> Ten TFTs were arbitrarily extracted from the manufactured liquid crystal drive panels, and the TFT element characteristics were measured. The drain current was measured when the drain voltage was 5.0 V and 0 V and 20 V were applied as the gate voltage. The on / off ratio (I _vg = 20 / I _vg = 0)
In the TFT of Example 8, the average was 7 × 10 ⁶ , and in the TFT of Comparative Example 8, the average was 2 × 10 ⁶ . From the above evaluation, it was found that the thin film forming method of the present invention is superior to the conventional thin film forming method. In addition, the number of thin film elements manufactured per hour was 120, and the thin film elements could be manufactured at a high manufacturing speed that has never been achieved.

[0073]

As described above, according to the thin film forming method of the present invention, the device characteristics of the thin film device formed by forming the thin film on the substrate are improved as compared with the conventional one, and the throughput of the thin film device is improved. It can be done. Further, by this, the cost reduction of the thin film element can be achieved. Specifically, it is possible to reduce the interface state with the substrate and the internal stress while improving the throughput.

Further, according to the thin film forming apparatus of the present invention,
It is possible to manufacture a thin film having improved device characteristics as compared with the conventional one and improved throughput.
Further, by this, the cost reduction of the thin film element can be achieved.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a thin film forming apparatus according to the present invention.

FIG. 2 is a configuration diagram showing another embodiment of the thin film forming apparatus according to the present invention.

FIG. 3 is a schematic view showing a solar cell formed by the thin film forming apparatus of FIG.

FIG. 4 is a configuration diagram showing still another embodiment of the thin film forming apparatus according to the present invention.

5 is a configuration diagram showing a liquid crystal driving panel formed by the thin film forming apparatus of FIG.

6A to 6C are manufacturing process diagrams of a liquid crystal drive panel, which sequentially explain the process of forming the TFT section of FIG.

[Simple explanation of symbols]

 101 vacuum container 103 substrate 106 RF electrode 108 gas introduction tube 110 microwave introduction window 114 MW plasma 115 RF plasma 116 shared region 201 vacuum container A 202 vacuum container B 203 vacuum container C 204 MW plasma 205 RF plasma 206 shared region 207 substrate 208 Sending roll 209 Winding roll 215 Heater

Claims (18)

[Claims] 1. A thin film forming method of forming a thin film on a substrate by accommodating a substrate inside a vacuum container capable of depressurizing the inside and introducing a raw material gas group of one or more kinds. At least two plasmas are generated inside, one of these plasma groups is the first plasma generated by the energy of electromagnetic waves having a frequency band of 1 to 100 MHz, and another is a frequency band of 1 to 100 GHz. The second plasma is generated by the energy of electromagnetic waves, and the first plasma region and the second plasma region are separated from each other with a slight shared region, and each thin film is formed in each plasma region. At the same time, the thin film forming method is characterized in that the substrate is moved along these plasma groups. 2. The pressure inside the first plasma is adjusted to the second pressure.
The method for forming a thin film according to claim 1, wherein the thin film forming method is made larger than plasma, and a part or all of the raw material gas group flows in the vacuum container from a region of the first plasma toward a region of the second plasma. 3. The substrate has a strip shape and is flexible,
The thin film forming method according to claim 1, wherein the thin film is continuously moved in the longitudinal direction of the substrate during the thin film formation. 4. The vacuum container is a first vacuum container, and a second vacuum container is connected to the first vacuum container through a separation passage through which a strip-shaped substrate can move. Almost similar to the cross section of the substrate, the shortest distance d between the inner wall of the separation passage and the substrate is 1 to 10 mm, and the length L with respect to the moving direction of the strip substrate satisfies the relation of L> 50 × d. A second source gas group that is a source gas group and has a source gas that is not included in the first source gas group in the second vacuum container The book film forming method according to claim 3, wherein the thin films are laminated on the same strip substrate. 5. A scavenging gas is introduced into the separation passage, and the scavenging gas is introduced from the separation passage into the first vacuum container and / or the second vacuum container.
The thin film forming method according to claim 4, wherein the thin film is flown toward a vacuum container. 6. The gas according to claim 5, wherein the scavenging gas is a gas selected from an inert gas, a gas forming the first raw material gas group, and a gas forming the second raw material gas group. The method of forming a book film described. 7. The thin film formation according to claim 4, wherein an exhaust port is provided in the separation passage, and a part of the first source gas group and / or the second source gas group is exhausted from the exhaust port. Method. 8. The thin film forming method according to claim 1, wherein the strong electric field direction of the electromagnetic wave introduced into the second plasma is substantially parallel to the substrate. 9. A semiconductor device having a pin junction and / or a pn junction manufactured by using the thin film forming method according to claim 1. 10. A thin film forming apparatus for forming a thin film on a substrate by accommodating a substrate inside a vacuum container capable of depressurizing the substrate and introducing one or more kinds of raw material gas groups. At least two plasma generating means for generating plasma are housed therein, and the first plasma generating means has a frequency band of 1-100.
The first plasma is generated by the energy of the electromagnetic wave of MHz, and the second plasma generating means is the one of generating the second plasma by the energy of the electromagnetic wave whose frequency band is 1 to 100 GHz. And the region of the second plasma are arranged separately from each other with a slight shared region, and each thin film is formed in each plasma region, and at the same time, the substrate is moved along these plasma groups. A thin film forming apparatus characterized in that substrate moving means is provided. 11. The internal pressure of the first plasma is set to be higher than that of the second plasma, and a part or all of the raw material gas group moves from a region of the first plasma toward a region of the second plasma in the vacuum container. The thin film forming apparatus according to claim 10, wherein the thin film forming apparatus is configured to flow. 12. The substrate has a strip shape and flexibility, and the substrate moving means is formed so as to continuously move the substrate in its longitudinal direction during thin film formation. The thin film forming apparatus described in 10 and 11. 13. The vacuum container is a first vacuum container, and a second vacuum container is connected to the first vacuum container through a separation passage through which a belt-shaped substrate can move. Almost similar to the cross section of the substrate, the shortest distance d between the inner wall of the separation passage and the substrate is 1 to 10 mm, and the length L with respect to the moving direction of the strip substrate satisfies the relation of L> 50 × d. And the second vacuum container uses a second source gas group of one or a plurality of types having a source gas that is not included in the first source gas group to form another thin film having a different property from that of the book film. 13. The book film forming apparatus according to claim 12, wherein the book film forming apparatus is formed so as to be laminated on the strip-shaped substrate. 14. A scavenging gas is introduced into the separation passage,
14. The thin film forming apparatus according to claim 13, wherein the scavenging gas flows from the separation passage toward the first vacuum container and / or the second vacuum container. 15. The scavenging gas is a gas selected from an inert gas, a gas forming the first raw material gas group, and a gas forming the second raw material gas group.
4. The film forming apparatus according to item 4. 16. The thin film formation according to claim 15, wherein an exhaust port is provided in the separation passage, and a part of the first source gas group and / or the second source gas group is exhausted from the exhaust port. apparatus. 17. The thin film forming apparatus according to claim 10, wherein the strong electric field direction of the electromagnetic wave introduced into the second plasma is substantially parallel to the substrate. 18. A semiconductor element having a pin junction and / or a pn junction, which is produced by using the thin film forming apparatus according to claim 10.