JP2002222770A - Vacuum treater and method of vacuum treatment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent pyropholic gas from reacting with gas having the susceptibility to burn in a vacuum treater, which uses simultaneously the pyropholic gas and the gas having the susceptibility to burn. SOLUTION: A pressure indicator is provided immediately before a vacuum treater provided with a piping for feeding raw gas and when the value of the pressure indicator becomes a value higher than a previously set value, the feed of the raw gas is stopped.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for performing a process on a substrate by introducing a raw material gas into a vacuum atmosphere, for example, a vacuum for forming a device by performing a vacuum process such as an etching apparatus and a CVD apparatus on the substrate. A processing device, and a process is performed on a substrate by introducing a raw material gas into a vacuum atmosphere,
The present invention relates to a vacuum processing method for forming a device.

[0002]

2. Description of the Related Art In recent years, vacuum processing for processing a substrate in a vacuum system has been applied to various fields, and among them, sputtering, plasma etching, plasma CVD, etc. have a wide application range and are put to practical use in various fields. .

As one example of such vacuum processing, Japanese Patent Application Laid-Open No.
Japanese Patent Application Laid-Open No. 4-145539 (hereinafter referred to as Document 1) discloses a technique for forming an electrophotographic image forming member using plasma CVD. According to the publication, a photoconductive layer made of amorphous silicon or amorphous germanium containing nitrogen atoms or oxygen atoms is formed by plasma CVD using a combination of various gases.

Japanese Patent Application Laid-Open No. 57-105745 (hereinafter referred to as Reference 2) discloses a technique using amorphous silicon containing nitrogen atoms and oxygen atoms as a barrier layer of a photoconductive member.

FIG. 7 schematically shows the structure of a vacuum processing apparatus 50 using plasma CVD and a source gas supply apparatus 100 outside the vacuum processing apparatus. In FIG. 7, a vacuum processing apparatus 50 connects an exhaust pipe 15 to a space sealed by a base plate 18, a cylindrical vacuum vessel 6 formed of a dielectric, and a lid 3, and vacuums by a vacuum pump (not shown). It can be held. A plurality of cylindrical substrates 7 are arranged inside the vacuum vessel 6, and each of the substrates has a dummy 2,
7 is installed. Further, a heater 5 is included in the base 7 so that the base 7 can be heated to a desired temperature. The rotating shaft 9 is connected to a motor 12 via a gear 10 so that each base can be rotated.

The source gas is supplied to an external source gas supply device 10.
Supplied from 0. The raw material gas supply device 100 includes a plurality of cylinders 101 to 104, pressure regulators 105 to 108, primary valves 109 to 112, a mass flow controller 113.
To 116, a bypass valve 117 to 120, a secondary valve 121 to 124, and a purge valve 125 to 128.

The raw material gas is charged into cylinders 101 to 104, and is reduced to an appropriate pressure by pressure regulators 105 to 108, and then adjusted to desired flow rates by primary valves 109 to 112 and mass flow controllers 113 to 116, respectively. After that, they are mixed with each other at the junction 131 via the secondary valves 121 to 125 and supplied to the vacuum processing apparatus 50 via the pipe 132. In the example of FIG. 7, there are four types of source gases, but these are usually increased or decreased according to the type of gas actually used.

The source gas supply apparatus 100 is provided with bypass valves 117 to 120 and purge valves 125 to 128, and further connected to a vacuum pump 130 via an exhaust pipe 133 and a valve 129.

The source gas supplied from the source gas supply device 100 is supplied to a plurality of nozzles 4 through a branch pipe 22. A plurality of orifices 32 are opened in the nozzle 4, and the raw material gas is discharged from the orifice 31 into the vacuum vessel 6.

According to the configuration of FIG. 7, when purging the mass flow controllers 113 to 116, the bypass valve 1
By opening 17 to 120 and opening the purge valves 125 to 128 and the valve 129, the exhaust pump 130 exhausts the mass flow controllers 1117 to 120. Further, the valve 129 is closed, and Ar (argon) and N ₂ (nitrogen) connected to one of the cylinders (for example, 101).
By opening a primary valve (for example, 109) with a purge gas such as this, the purge gas is filled in the mass flow controller.

A power supply 20 is connected to the vacuum processing apparatus 50 via a matching box 21, and high-frequency power supplied from the power supply 20 is supplied via a connection terminal 29 to a branch plate 25.
And is distributed to the plurality of electrodes 1, transmitted through the vacuum vessel 6 and emitted to the discharge space 23, decomposes the source gas, generates glow discharge, and vacuum-treats the substrate.

At the lower end of the electrode 1, a capacitor 30 for phase adjustment is provided to increase the ease of matching and the stability of discharge. In addition, a shield 19 is installed at the outermost part of the vacuum processing device 50 to prevent leakage of high-frequency power.

According to such an apparatus, a desired vacuum treatment can be performed on the substrate by appropriately selecting and using various source gases.

[0014]

However, among various types of source gases, there are cases where source gases that are not preferably mixed with each other are included.

For example, it is known that when a gas having a self-combustion property and a gas having a combustion-supporting property are mixed, they react with each other even under conditions of normal temperature and normal pressure.

Among the gases used for vacuum processing, gases having self-combustibility include SiH ₄ (monosilane), Si ₂ H ₆ (disilane), GeH ₄ (germane), B ₂ H ₆ (diborane), PH ₃
(Phosphine) and the like. Further, as the gas having a supporting property, O ₂ (oxygen), NO (nitrogen monoxide), NO ₂ (nitrogen dioxide), N ₂ O (nitrous oxide), Cl ₂ (chlorine), F ₂ (fluorine) ) Etc. are raised.

In actual vacuum processing, there are many cases where the above-described self-combustible gas and the above-described supporting gas are used simultaneously. For example, when a silicon oxide film is formed by plasma CVD, SiH ₄ or Si ₂
In some cases, H ₆ and O ₂ or NO for introducing oxygen atoms may be used at the same time. For example, in Reference 1, SiH ₄ , Si ₂ H ₆ ,
Further, GeH _{4 and the} like are disclosed as gases for forming amorphous germanium, and O ₂ and NO are disclosed as suitable gases for introducing oxygen atoms and nitrogen atoms into these gases. In Reference 2, SiH _{4 is} used as a method for forming amorphous silicon containing oxygen atoms.
There is disclosed an example of mixing and using O ₂ , and there are many examples of using a mixture of a self-combustible gas and a supporting gas for reasons of device characteristics.

When the self-combustion gas and the combustion-supporting gas are used at the same time, the gases are mixed at a pressure lower than the reaction limit in order to prevent the gases from reacting in the pipe. Care must be taken in determining the vacuum processing conditions.

However, even under the above-mentioned conditions, the pressure may temporarily increase in the piping due to, for example, a failure of the mass flow controller or breakage of the valve, which may cause a mutual reaction. is there. In particular, as shown in FIG. 7, in a source gas supply device provided with a bypass valve to improve the purge efficiency, an unintended flow rate of the source gas flows into the pipe due to breakage of the bypass valve and the like, and the reaction is stopped. It is more likely to cause it.

Although such cases are rare, once the reaction occurs, a powdery reaction product is formed inside the pipe and dust is generated. As a result, the entire vacuum processing apparatus is contaminated with dust, and the quality of the device is reduced. Further, even if measures such as cleaning or replacing the inside of the pipe for the contaminated pipe are taken, the apparatus becomes unavailable for a corresponding period, which results in a decrease in the operation rate of the apparatus.

[0021] An object of the present invention is to overcome the above problems and to simultaneously use a self-combustible gas and a supporting gas in order to prevent the reaction between the self-burning gas and the supporting gas in the gas supply pipe. Another object of the present invention is to provide a vacuum apparatus capable of preventing contamination of a vacuum apparatus by a reaction product and supplying a high-quality device with a high operation rate.

[0022]

According to the present invention, a vacuum processing apparatus and a vacuum processing method are configured as described below to solve the above-mentioned problems.

That is, a decompressible reaction having a source gas supply means for supplying a source gas having a combustion supporting gas and a self-combustion gas disposed in a reaction vessel, and at least a base mounting portion A vacuum processing apparatus having a vessel, wherein the raw material gas is supplied into the reaction vessel from a gas discharge nozzle inside the reaction vessel via a pipe from outside the reaction vessel, and is connected to the reaction vessel in the pipe. The present invention relates to a vacuum processing apparatus provided with a pressure gauge immediately before a portion including a cut portion, and having a mechanism for shutting off the supply of the source gas when the pressure gauge exceeds a predetermined value.

Further, at least a substrate is disposed in a decompressible reaction vessel having a gas supply nozzle for supplying a source gas composed of a self-combustible gas and a supporting gas in the reaction vessel;
Vacuum processing in which a source gas including a self-combustible gas and a supporting gas supplied from a pipe in the reaction vessel is introduced into the reaction vessel from the gas supply nozzle, and a vacuum process is performed on the substrate in the reaction vessel. A method of shutting off the supply of the source gas based on a pressure detected by a pressure gauge provided immediately before including a connection portion of the pipe with the reaction vessel during a vacuum processing step. The present invention relates to a vacuum processing method.

[Operation] According to the vacuum processing apparatus and the vacuum processing method of the present invention, even if the pressure inside the pipe suddenly increases due to an unexpected situation such as breakage of a mass flow controller or a valve, the pipe processing can be performed. The supply of gas is shut off before the internal pressure exceeds the reaction limit between the self-combustible gas and the supporting gas, so that contamination of the piping and the reaction vessel by reaction products can be prevented.

Normally, in order to uniformly supply the source gas to the vacuum processing apparatus, it is necessary to provide an orifice in the nozzle and a differential pressure between the nozzle and the discharge space as in the apparatus shown in FIG. In this case, the pressure inside the nozzle is about 10 times higher than the discharge space, and depending on the conditions, a pressure difference of about 1000 times may be applied.

In such a case, since the pressure in the piping rises more rapidly than the pressure in the reaction vessel, monitoring the inside of the reaction vessel, for example, is not very effective. In the present invention, by installing a pressure gauge on the pipe immediately before the nozzle connected to the reaction vessel, by directly monitoring the pressure at the site where the reaction is most likely to occur, the progress of the reaction in the pipe is effectively prevented. It is possible to do.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention and the operation thereof will be specifically described below with reference to the drawings.

FIG. 1 is a diagram schematically showing an example of a vacuum processing apparatus and a source gas supply apparatus according to the present invention. In the apparatus shown in FIG. 1, a pressure gauge 134 is provided immediately before the nozzle 32 (branch pipe 22) on the piping from the raw material gas supply apparatus to the vacuum processing apparatus. FIG. 2 conceptually shows a control system of the apparatus shown in FIG. In FIG. 2, the signal of the pressure gauge 134 is connected to the control device 201 so that the pressure in the pipe can be monitored. The output of the control device 201 is supplied to the valves 109-1 through the electromagnetic valves 202-218.
Connected to 29, each valve can be opened and closed. Also,
Other outputs are connected to mass flow controllers 113-116 to control the flow of each gas.

The controller 201 controls the opening / closing of a valve and the flow rate of a mass flow controller in accordance with a predetermined flow rate pattern of the raw material gas and each gas flow rate instruction, and feeds the raw material gas into the vacuum processing apparatus at a desired flow rate condition. Supply.

The control device 201 continuously monitors the signal of the pressure gauge 134 during the process, and when the pressure value exceeds a predetermined value, controls to cut off the supply of the raw material gas. The supply of the raw material gas is shut off by the secondary valve 1
Closing 21 to 124 is sufficient to obtain the effect of the present invention, but it is also effective to close primary valves 109 to 112 at the same time.

In the present invention, the vacuum gauge 134 may be installed immediately before the nozzle 32 connected to the vacuum vessel 6.
This is important in preventing undesired reactions between the supporting gas and the self-burning gas.

The piping for supplying the raw material gas to the vacuum processing apparatus is provided for uniformly supplying the raw material gas to the vacuum processing apparatus, for branching into a plurality of flow paths, or for mechanical connection with a nozzle. For the reason described above, the most complicated configuration is likely to be obtained. For this reason, an unintended reaction between the supporting gas and the self-burning gas is likely to occur structurally due to the influence of the flow of the raw material gas in the pipe.

When the substrate needs to be heated in the vacuum treatment process, the residual heat heats the pipe immediately before the nozzle connected to the reaction vessel, so that the combustion supporting gas and the self-combustion gas are thermally heated. During this time, unintended reactions may be promoted.

In view of the above circumstances, in the pipe for supplying the raw material gas, immediately before the nozzle connected to the reaction vessel, the part where the undesired reaction is most likely to occur between the supporting gas and the self-burning gas. It can be said that.

According to the present invention, by directly detecting and controlling the pressure in the portion where the undesired reaction between the above-described combustible gas and the self-combustible gas is most likely to occur, that is, immediately before the nozzle, control is performed. Unintended reactions between the gas and the self-combustible gas can be most effectively prevented.

In the apparatus having a plurality of nozzles as shown in FIG. 1, a well-designed branch pipe 22 is indispensable for uniformly distributing the source gas to each nozzle. Immediately before includes the branch pipe 22 itself or immediately before the branch pipe 22. Therefore, in the present invention, the pressure gauge 134 is connected to the branch pipe 22 or the branch pipe 22.
However, when the pressure gauge 134 is provided in the branch pipe 22, the source gas may be biased when the raw material gas is distributed to a plurality of nozzles. It is desirable to consider the method.

In the present invention, the pressure point at which the supply of the self-combustible gas and the supporting gas is stopped is set to be lower than the reaction limit pressure of the self-combustible gas and the supporting gas used. However, this pressure varies depending on conditions such as the combination of gases used, the flow rate ratio, and the temperature. For example, a combination of gases having a self-combustibility when mixed with each other even at normal temperature and normal pressure is very commonly used. In addition, even under a pressure condition in which a reaction does not occur when a self-combustible gas and a supportive gas are simply mixed, if a gas flows in a pipe, a turbulent flow generated in the gas flow may occur. In some cases, the reaction progresses locally due to the influence of, and it is difficult to determine the reaction uniquely. Therefore, it is desirable that the pressure point at which the supply of the self-combustible gas and the supporting gas is stopped be determined empirically in accordance with each device configuration and actual use conditions.

In the present invention, the type of the pressure gauge installed immediately before the nozzle portion may be any type as long as it can output a pressure signal to the control device. For example, Pirani gauges, ionization type vacuum gauges, capacitance manometers, are used by obtaining electrical signals from vacuum gauges such as the Bourdon tube.Capacity manometers have a simple structure of the gas contact part, It is most suitable from the viewpoint that the source gas is not decomposed or deposited by heat in the meter.

FIG. 3 is an example of a flow diagram schematically showing the gas supply control of the present invention when the vacuum processing apparatus shown in FIG. 1 is used. In the flowchart of FIG. 3, the control is started by a predetermined control or an external gas supply command (401). Next, the controller 201 sets the primary valves 109 to 1 of the gas type set in the gas supply command 401.
The 12 and secondary valves 121 to 124 are opened (402).

After opening the primary valves 109 to 112 and the secondary valves 121 to 124 (402), the flow rate setting is output to the mass flow controllers 113 to 116 (40).
3). At this time, the gas flow rate may gradually reach the setting using the slow start function of the mass flow controller.

When the flow rate of the source gas is stabilized, vacuum processing is started (404). During this time, the flow rate and type of the source gas can be changed by a predetermined program or an external command.

After the end of the process (405), the primary valve 109
To 112 and the secondary valves 121 to 124 are closed (40
6), a series of operations ends (409).

The control device 201 includes primary valves 109 to 11
At the same time when the secondary and secondary valves 121 to 124 are opened (402), the indicated value (P1) of the vacuum gauge 134 is monitored (407).
When 1 becomes equal to or more than the preset value (P2), an alarm is immediately issued (408), the valve is closed (406), and a series of operations is terminated (409).

In the present invention, if the control shown in FIG. 3 is performed, even if the flow rate of the self-burning gas or the supporting gas increases due to an unexpected situation, the reaction between the self-burning gas and the supporting gas can be prevented. Since the supply of each gas is stopped before the pressure that occurs occurs, contamination of the vacuum processing apparatus and the piping by the reaction product can be prevented.

According to the present invention, the self-combustion gas and the combustion-supporting gas are supplied from the source gas supply device through separate pipes, merged immediately before the vacuum processing device, and cut off immediately before the junction. A valve can be provided.

FIG. 4 shows that the self-combustion gas and the combustion-supporting gas are supplied from the raw material gas supply device through separate pipes, joined immediately before the reaction vessel, and then supplied to the reaction vessel. An example of an apparatus in which a valve for shutting off a source gas is installed in a pipe is schematically illustrated. In the device of FIG.
The cylinders 151 to 153 are filled with a self-combustible gas and other gases, and the cylinder 154 is filled with a combustible gas. Each cylinder has a pressure regulator 155-158, a primary valve 159-162, a mass flow controller 163-1.
66, bypass valves 167 to 170, secondary valve 17
1 to 174 and purge valves 175 to 178 are connected. Gases such as self-combustible gas and inert gas are supplied to the
5. Further, the combustion supporting gas is individually supplied to the vacuum processing device via the pipe 137, and is joined at the junction 131 immediately before the branch pipe 22 via the shutoff valves 136 and 138, and is connected to the branch pipe 22. The pressure gauge 134 is connected from the junction 131 to the branch pipe 22.
Connected to the piping.

In the apparatus shown in FIG. 4, when the indicated value of the pressure gauge 134 indicates a predetermined value or more, at least the secondary valves 171 to 174 and the shut-off valve 13 are simultaneously operated.
6, 138 are closed. In this case, the presence of the mixture of the self-combustible gas and the supporting gas is caused by the shut-off valves 136 and 138.
More limited to the vacuum processing device side. In addition, since a shut-off valve is provided immediately before the junction, the exhaust space can be reduced even when the pressure in the pipe rises. The effect of preventing the reaction of the flammable gas is further enhanced. This configuration,
For example, it is particularly effective when the pressure in the piping must be close to the reaction limit between the self-combustible gas and the supporting gas due to process restrictions.

That is, when the pressure in the piping is close to the reaction limit of the self-combustible gas and the supporting gas, the pressure setting for shutting off the supply of the raw material gas is necessarily set to the reaction limit. In this case, even if the supply of the raw material gas is shut off, the actual pressure of the pipe may exceed the reaction limit due to a problem such as the response speed of the control system. In this case, the gas remaining in the pipe is exhausted, and the pressure in the pipe can be reduced in a short time.
It is important in preventing the reaction.

According to the present invention, in the apparatus shown in FIG.
When the self-combustion gas or the combustion-supporting gas is not supplied, the valve of the pipe to which the gas is not supplied may be closed.

For example, when only the self-combustible gas is required for the vacuum treatment process and no supporting gas is required, the shut-off valve 138 can be closed.
Similarly, when only the supporting gas is required and the self-burning gas is not required, the shut-off valve 136 can be closed. When such control is performed, by shutting off a pipe through which the source gas does not flow, a so-called dead space in which the source gas stays in the pipe, can be minimized. In particular, when forming a multi-layer device such as an electrophotographic photoreceptor, one layer requires both a self-combustible gas and a supporting gas, and another layer requires only a self-combustible gas. In some cases. In such a case, it is possible to prevent the combustion-supporting gas from entering the dead space into the self-burning gas. This control can be automatically performed by setting the shutoff valves 136 and 138 to close when the flow rate of the gas sent from the upstream side becomes zero.

In the apparatus shown in FIG. 4, the junction 131 must be located immediately before the reaction vessel. In the present invention, the term "immediately before the reaction vessel" means a member for supplying the source gas into the reaction vessel in the source gas supply path, that is, immediately before the nozzle. However, in an apparatus having a plurality of nozzles as shown in FIG. 4, a well-designed branch pipe 22 is indispensable in order to evenly distribute the source gas to each nozzle. 22 itself or immediately before the branch pipe 22 are included. Therefore, in the present invention, the pressure gauge 134 can be provided on the branch pipe 22 or the pipe immediately before the branch pipe 22.
In the case where 4 is provided, when the raw material gas is distributed to a plurality of nozzles, the gas may be biased. Therefore, it is desirable to consider the type and installation method of the pressure gauge.

In a configuration in which a branch pipe is not required, such as when a single nozzle is used, “immediately before the reaction vessel” means immediately before the nozzle.

In the apparatus shown in FIG. 4, the junction 131 is located immediately before the branch pipe 22. The specific range immediately before varies depending on the shape of the piping and the scale of the entire apparatus, but it is desirable that the distance be as short as possible in view of the apparatus configuration. The distance between the branch pipe 22 and the junction 131 is determined by the distance between the source gas supply apparatus and the reaction vessel. The rule of thumb is to keep it less than one tenth of the distance. In general, the distance between the branch pipe 22 and the junction is about 20 mm or more due to a design problem of the piping system.

It is also desirable that the distance between the shut-off valves 136 and 138 and the junction 131 is as short as possible. By shortening this distance, the region where the self-combustible gas and the combustion-supporting gas coexist is reduced. The effect of reducing the possibility that the gases react with each other is increased. In addition, since the dead space in which the source gas remains remains is minimized, contamination can be further reduced when forming a multilayered deposited film. Specifically, the distance between the shutoff valves 136 and 138 and the junction 131 is desirably set to be approximately equal to the distance between the branch pipe 22 and the junction 131.

The above-described effects of the present invention can be obtained in any vacuum processing apparatus and vacuum processing method using a self-combustible gas and a supporting gas at the same time. Among them, plasma CVD using a relatively large number of source gases as compared with other processes is particularly effective in preventing contamination due to the reaction between the self-combustible gas and the supporting gas.

[0057]

Embodiments of the present invention will be described below in detail.

Example 1 Using the apparatus shown in FIG. 1, a photoconductor for electrophotography having a layer structure in which a charge injection blocking layer, a photoconductive layer and a surface layer were laminated on a substrate was formed. The procedure for preparing the electrophotographic photoreceptor shown in FIG. 1 is roughly as follows. First, the substrate 7 previously degreased and washed is set on the rotating shaft 9 in the vacuum vessel 6, and the inside of the vacuum processing device 50 is evacuated.
(Not shown) to exhaust the pressure in the reaction vessel to 0.1 Pa or less.

Next, an inert gas such as Ar is introduced into the reaction vessel from the raw material gas supply means 100. For example, a case where Ar is filled in the cylinder 101 as an inert gas will be described as an example, but it is assumed that another raw material gas is appropriately filled in another cylinder. The primary valve 109 and the secondary valve 121 are opened, and the mass flow controller 11
Ar is supplied to the vacuum processing apparatus 50 via the third valve 3. At this time, the space between the primary valve 109 and the secondary valve 121 may be evacuated via the purge valve 125. That is, after the exhaust pump 130 is operated and the valve 129 is opened, the purge valve 125 and the bypass valve 117 are opened.
Is opened, and the piping between the primary valve 109 and the secondary valve 121 and the inside of the mass flow controller 113 are exhausted.
By performing the above procedure, the gas accumulated between the primary valve 109 and the secondary valve 121 is exhausted, and the vacuum processing device 50
Gas can be prevented from protruding into the inside.

Next, the bypass valve 117 is closed, the primary valve 109 is opened, and Ar gas is introduced. At this time, the mass flow controller 113 is closed, and when the output of the mass flow controller 113 is stabilized, the purge valve 125 is closed, and then the secondary valve 121 is opened. Further, a flow rate is set in the mass flow controller 113, and a desired flow rate is introduced into the reaction vessel.

Next, an exhaust valve (not shown) provided in the exhaust pipe 15 is operated while watching a pressure gauge (not shown) to adjust the pressure of the reaction vessel to a desired pressure. The substrate 7 is heated to a desired temperature of 20 ° C. to 500 ° C. When the temperature of the substrate 7 reaches a desired temperature, the flow of Ar is stopped, and the pressure in the reaction vessel is exhausted again to 0.1 Pa or less.

Next, the desired source gas for the charge injection blocking layer is supplied from the source gas supply means 100 in the above-described procedure, and the exhaust valve provided on the exhaust pipe 15 is operated while watching the pressure gauge again, and Is adjusted to the desired pressure. When the pressure is stabilized, the output of the high frequency power supply 20 is set to a desired power, the matching box 21 is adjusted, and a glow discharge is generated in the discharge space 23. As a result, the source gas is decomposed and a deposited film is formed on the base 7. At this time, by rotating the base 7 by the motor 12, a deposited film can be uniformly formed on the base 7 over the entire circumference.

When the charge injection blocking layer having the desired thickness is formed, the raw material gas is gradually changed from the gas for forming the charge injection blocking layer to the gas for forming the photoconductive layer. Form a layer. Thereafter, after the formation of the photoconductive layer is completed, the raw material gas is gradually switched from the gas for forming the photoconductive layer to the gas for forming the surface layer, and the variable layer is formed. After forming the surface layer of the desired thickness, the supply of the high-frequency power and the source gas is stopped, the glow discharge is stopped, and the formation of the deposited film is completed.

In this example, an electrophotographic photosensitive member was prepared under the conditions shown in Table 1.

[0065]

[Table 1]

Under the conditions shown in Table 1, NO was introduced to form amorphous silicon oxide (a-SiO) in the charge injection blocking layer of the electrophotographic photosensitive member. The indicated value of the pressure gauge 134 during the formation of the charge injection blocking layer was 153 Pa. Under this pressure condition, even if SiH ₄ and NO are mixed, they do not react with each other.

Next, based on the conditions for forming the charge injection blocking layer shown in Table 1, the flow rate of SiH ₄ and NO was changed while maintaining the flow rate ratio, and the relationship with the indicated value of the pressure gauge 134 was examined. Also,
The control device was set so as to shut off the supply of the raw material gas when the indicated value of the pressure gauge showed 400 Pa or more. The result is shown in FIG.

From the results shown in FIG. 5, it can be seen that the pressure in the piping increases almost in proportion to the increase in the flow rate of the source gas. Also, the flow rates of SiH ₄ and NO were set to 400 mL / min (n
ormal), 27mL / min (normal) and pressure gauge 1
When the indicated value of 34 exceeded 400 Pa, the valve was closed and the source gas was shut off.

In this embodiment, when the flow rates of the self-combustion gas and the combustion-supporting gas increase, each gas does not reach the pressure at which the two gases start reacting (when the indicated value of the pressure gauge 134 exceeds the set value). The operation of shutting off the source gas is simulated in a similar manner. For example, if the bypass valve fails to function due to breakage of the bypass valve or trouble in the control system during supply of the source gas, FIG. In this apparatus, the raw material gas flows at a flow rate of about 50 L / min (normal). Extrapolating from the graph of FIG. 5, the pressure in the pipe exceeds the atmospheric pressure, and the reaction between SiH ₄ and NO may occur. The possibilities increase.

According to the present invention, even in such a case, the supply of the raw material gas can be cut off before the reaction between the self-combustible gas and the supporting gas occurs inside the pipe by detecting the pressure in the pipe.
Contamination in the pipe can be effectively prevented.

Embodiment 2 Using the apparatus shown in FIG. 1, the effect of the present invention is simulated on the assumption that the bypass valve is opened during the supply of the source gas and a large amount of the source gas flows. Verification was performed using Ar.

First, the cylinder 101 is filled with Ar and supplied to the reaction vessel at a flow rate of 100 mL / min (normal). At this time, the control device is set so that the secondary valve 121 is closed and the supply of Ar is shut off when the indicated value of the pressure gauge 134 indicates 500 Pa or more.

When the flow rate of Ar, the internal pressure of the reaction vessel, and the indicated value of the pressure gauge 134 are stabilized, the bypass valve 1
17 was opened to reproduce the situation where a large amount of raw material gas flowed into the reaction vessel, and the change in the indicated value of the pressure gauge 134 was recorded.

(Embodiment 3) Using the apparatus shown in FIG. 4, as in Embodiment 2, it is assumed that the bypass valve is opened during the supply of the raw material gas and a large amount of the raw material gas flows in the present invention. The effect of was simulated. In this embodiment, the cylinder 1
Assuming a case where a self-combustible gas is supplied from 51 and a supportive gas is supplied from a cylinder 154, the simulation was performed using Ar for both the self-combustible gas and the supportive gas.

First, A is applied to the cylinder 151 and the cylinder 154.
is filled, and Ar is supplied from the cylinder 151 via the primary valve 159, the mass flow controller 163, the secondary valve 171, the pipe 135, and the shutoff valve 136 to 90 mL / min (n
ormal), and the primary valve 162 from the cylinder 154,
Ar is supplied through the mass flow controller 166, the secondary valve 174, the pipe 137, and the shutoff valve 138 at a flow rate of 10 mL / min.
(normal) to the reaction vessel. At this time, the control device is set so that the shutoff valves 136 and 138 are closed and the supply of Ar is shut off when the indicated value of the pressure gauge 134 indicates 200 Pa or more.

When the flow rate of Ar, the internal pressure of the reaction vessel, and the indicated value of the pressure gauge 134 are stabilized, the bypass valve 1
67 was opened to reproduce the situation where a large amount of source gas flowed into the reaction vessel, and the change in the indicated value of the pressure gauge 134 was recorded.

The results of Examples 2 and 3 are shown in FIG. According to the results of FIG. 6, immediately after the bypass valve 167 is opened, 837 Pa in the case of the second embodiment, and
The pressure rose to 848 Pa. This is due to the responsiveness of the control device, solenoid valve and valve, etc., which causes a delay in the time from when the piping pressure actually exceeds 500 Pa until the source gas is shut off, and almost instantaneously exceeds the set value. It is considered that the pressure inside the pipe has increased due to
It can be seen that the pipe pressure is rapidly decreasing.

Embodiments 2 and 3 show that in an extreme situation where the bypass valve is unexpectedly opened, the pressure of the piping may rise significantly beyond the set pressure of the source gas shutoff. I have. In such a case, the probability of causing a reaction between the self-combustible gas and the supporting gas can be reduced by rapidly reducing the pressure inside the pipe.

Therefore, in the apparatus of the present invention, even in the situation as in Embodiment 2, the source gas is shut off and the source gas in the pipe is exhausted through the reaction vessel at the same time, thereby reducing the pressure in the pipe. By reducing the probability that the self-combustible gas and the supporting gas react with each other,
This shows that contamination by reaction products can be effectively prevented.

Further, as shown in FIG. 4, in a device in which the self-combustible gas and the combustion-supporting gas are introduced into separate pipes and joined immediately before the branch pipe, and the shut-off valve is arranged immediately before the junction, the self-combustible gas is used. Since the region where the mixed gas of the gas and the supporting gas is present is limited, it is shown that the pressure decreases more quickly than in the case of the first embodiment. That is, according to the apparatus shown in FIG. 4, the reaction between the self-combustible gas and the supporting gas can be more effectively prevented than the apparatus shown in FIG.

In the apparatus used in Examples 2 and 3, even if the pressure of the piping exceeded 850 Pa, no reaction between the self-combustible gas and the supporting gas occurred.

Example 4 An electrophotographic photosensitive member was prepared in the same manner as in Example 1 using the apparatus shown in FIG.

Here, the procedure will be described by taking as an example a case where Ar is filled into the cylinder 151 as an inert gas and NO is filled into the cylinder 154 as a combustion supporting gas. It is assumed that the other source gas is appropriately filled in the other cylinder.

First, an inert gas such as Ar is introduced into the evacuated vacuum processing apparatus 50 in the same procedure as in the first embodiment. At this time, the secondary valve 171, the bypass valve 167, and the purge valve 175 are opened, and the primary valve 15 is opened.
The gas accumulated in the pipe between the valve 9 and the shut-off valve 136 may be exhausted. Next, the bypass valve 167 is closed, the primary valve 159 is opened, and Ar gas is introduced. At this time, the mass flow controller 163 is closed, and when the output of the mass flow controller 163 is stabilized, the purge valve 175 is closed, and then the shutoff valve 136 is opened. Further, a flow rate is set in the mass flow controller 163, and a desired flow rate is introduced into the vacuum processing device 50.

Subsequently, after heating the substrate 7 according to the above-described procedure, a source gas for forming a charge injection blocking layer is introduced according to the above-described procedure. When the NO gas is supplied from the cylinder 154, the bypass valve 170, Purge valve 178,
The secondary valve 174 is opened and the piping between the primary valve 162 and the shutoff valve 138 and the mass flow controller 16 are opened.
The gas accumulated in 6 may be exhausted. Next, the bypass valve 170 is closed, the primary valve 162 is opened, and NO gas is introduced. At this time, the mass flow controller 166 is closed, and when the output of the mass flow controller 166 is stabilized, the purge valve 178 is closed, and then the shutoff valve 138 is opened. Further, a flow rate is set in the mass flow controller 166, and a desired flow rate is introduced into the vacuum processing device 50. Further, other source gases can be introduced in the same procedure as in Example 1 in parallel with the introduction of NO.

Thereafter, an electrophotographic photosensitive member was prepared according to the same procedure as in Example 1.

In this embodiment, when NO is not supplied from the cylinder 154 through the primary valve 162, the mass flow controller 166, the secondary valve 174, and the pipe 137, the shut-off valve 138 is closed and the pipe 137 flows through the pipe 137. A control to separate from the road was used. Specifically, Table 1
When the variable layer was formed following the formation of the charge injection blocking layer under the conditions described above, the shutoff valve 138 was closed when the flow rate of NO became 0 mL / min (normal).

The photoreceptor thus produced is used in an electrophotographic apparatus.
(NP-6750 manufactured by Canon Inc. was modified for experiments), and the charging ability, residual potential, and photosensitivity were evaluated. Each item was evaluated by the following method.

Charging ability: process speed of 380 mm
/ sec, pre-exposure 4lux · sec (wavelength 700nm) Charging current 1000μ
Under the conditions of A, the dark area potential on the surface of the electrophotographic photosensitive member was measured with a surface voltmeter (Model 344, manufactured by TREK) set at the developing device position of the electrophotographic apparatus, and the result was defined as the charging ability.

The charging ability was evaluated as ◎: good, slightly inferior to ○, but no effect on image formation. X: poor in charging ability, affecting image formation.

Residual potential: The electrophotographic photoreceptor is charged to 400 V at a dark potential, and a filter is used to irradiate a halogen lamp, excluding light having a wavelength of 550 nm or more, with a light amount of 2.0 lux · sec. Measure the potential with an electrometer and determine the residual potential.

The residual potential was evaluated as ◎: good, slightly inferior to ○, but no effect on image formation. X: poor residual potential, affecting image formation.

Light sensitivity: The electrophotographic photoreceptor is exposed at dark potential.
Charged to 400V, irradiate with halogen lamp light excluding light of wavelength 550nm or more using a filter,
The light amount is adjusted so as to be 50 V, and the light amount at that time is defined as light sensitivity.

The light sensitivity was evaluated as ◎: good, slightly inferior to ○, but no effect on image formation. X: poor in light sensitivity, affecting image formation.

Example 5 Using the apparatus shown in FIG. 4, a photosensitive member for electrophotography was prepared under the conditions shown in Table 1 without controlling to close the shut-off valve 138 when no supporting gas was used. Specifically, after the formation of the charge injection blocking layer, the variable layer was formed, and the shutoff valve 138 was kept open even after the flow rate of NO was set to 0 mL / sec (normal) (during the formation of the photoconductive layer).

The electrophotographic photoreceptor thus produced was evaluated for charging ability, residual potential and photosensitivity in the same manner as in Example 4.

The results of Example 4 and Example 1 are shown in Table 2. The electrophotographic photoconductor formed in Example 1 was evaluated in the same manner as in Example 4, and the results are shown in Table 2.

[0098]

[Table 2]

From the results shown in Table 2, in Example 4, Example 1
As in the case of the above, good results were obtained. On the other hand, Example 5
In the electrophotographic photoreceptor of Example 4, the residual potential and the light sensitivity
Was slightly inferior to. This is because, in the case of Comparative Example 1, since the shutoff valve 138 was not closed even after the flow rate of NO was set to 0 mL / sec (normal) (during formation of the photoconductive layer), the pipe 137 became a dead space.
It is considered that the NO gas retained in 37 caused contamination during formation of the photoconductive layer.

As described above, when the shut-off valve of the pipe on the side to which the source gas is not supplied is controlled to be closed during the vacuum processing, particularly in the case of continuously forming a multi-layered deposited film, contamination is prevented. It turns out to be extremely effective. On the other hand, even in the case of the fifth embodiment in which the control to close the shutoff valve of the pipe on the side not supplying the source gas during the vacuum processing is not performed, the vacuum processing in which the gas type used during the vacuum processing does not change, for example, a single layer It is clear from the results of Example 3 that there is no possibility of contamination in the case of forming a deposited film or the like having the configuration, and that it is sufficient to obtain the effects of the present invention.

As described above, from the results of Examples 1 to 5,
According to the method of the fourth embodiment, the dead space can be minimized even when the self-combustible gas and the supporting gas are supplied from the raw material gas supply device to the individual containers just before the reaction vessel. It has been found that the contamination of the piping due to the reaction between the self-combustible gas and the supporting gas can be effectively prevented without affecting the characteristics of the pipe.

[0102]

As described above, according to the present invention, even in a vacuum processing apparatus or a vacuum processing method using a self-combustible gas and a supporting gas, the reaction by mixing the self-burning gas and the supporting gas is performed. Generation of adult organisms can be effectively prevented. In addition, in a mode in which the self-combustion gas and the combustion-supporting gas are supplied from the source gas supply device through separate pipes and are joined and supplied immediately before the reaction vessel, a shutoff valve is provided immediately before the junction to supply the source gas. By using the control to close the shut-off valve of the pipe on the side that is not used, the generation of reaction products due to the mixture of the self-burning gas and the supporting gas can be more effectively prevented, and the contamination of the raw material gas can be prevented. Devices with various characteristics can be supplied.

[Brief description of the drawings]

FIG. 1 is a schematic view of a vacuum processing apparatus and a source gas supply mechanism used in the present invention.

FIG. 2 is a conceptual diagram of a control system of a vacuum processing apparatus used in the present invention.

FIG. 3 is a schematic diagram of a flow of a vacuum processing method of the present invention.

FIG. 4 is a schematic diagram of a vacuum processing apparatus and a source gas supply mechanism for supplying a self-combustible gas and a supportive gas through separate pipes.

FIG. 5 is a diagram showing a relationship between a raw material gas flow rate and a pipe pressure in Example 1.

FIG. 6 is a diagram showing a change in piping pressure in Examples 2 and 3.

FIG. 7 is a schematic view of a conventional vacuum processing apparatus and a source gas supply mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electrode 2 Dummy 3 Lid 4 Nozzle 5 Heater 6 Vacuum container 7 Substrate 9 Rotation axis 10 Gear 12 Motor 15 Exhaust piping 18 Base plate 19 Shield 20 Power supply 21 Matching box 22 Branch pipe 23 Discharge space 25 Branch plate 29 Connection terminal 30 Capacitor 32 Orifice 50 Vacuum processing apparatus 100 Source gas supply means 101-104, 151-154 Cylinder 105-108, 155-158 Pressure regulator 109-112, 159-162 Primary valve 113-116, 163-166 Mass flow controller 117-120, 167 ~ 170 Bypass valve 121 ~ 124,171 ~ 174 Secondary valve 125 ~ 128,175 ~ 178 Purge valve 129 Valve 130 Exhaust device 131 Confluence 132,135,137 Piping 134 Pressure gauge 136,138 Shutoff valve 201 Control device 202,203 , 204, 218 Solenoid valve

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Daisuke Tazawa 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Yukihiro Abe 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon F term in reference (reference) 4K030 EA01 EA06 FA03 HA15 JA09 KA11 5F045 AA08 AB32 AC01 AC02 AC03 AC11 AC15 AC16 BB20 CA16 DP28 EE01 EF17 EH15 GB06

Claims (10)

[Claims] 1. A decompressible reaction vessel having a source gas supply means for supplying a source gas having a combustion supporting gas and a self-combustion gas disposed in a reaction vessel, and at least a portion where a base is provided. Wherein the source gas is supplied into the reaction vessel from a gas discharge nozzle inside the reaction vessel via a pipe from outside the reaction vessel, and connected to the reaction vessel in the pipe. A vacuum processing apparatus comprising a pressure gauge immediately before including the portion, and a mechanism for shutting off the supply of the source gas when the pressure gauge exceeds a predetermined value. 2. The self-combustible gas and the supporting gas are respectively supplied to the reaction vessel through individual pipes, and each pipe has a junction just before the reaction vessel, and each pipe has a junction from the junction to the gas discharge nozzle. 2. The vacuum processing apparatus according to claim 1, wherein a pressure gauge is provided between the two pipes, and a valve for shutting off gas supply is provided immediately before a junction of each pipe. 3. The vacuum processing apparatus according to claim 1, further comprising a control device having a function of automatically performing a control to cut off the supply of the combustion supporting gas and the self-burning gas. 4. The reaction according to claim 1, wherein the reaction performed in the reaction vessel is a reaction for forming a deposited film by a plasma CVD method in which a source gas is decomposed by high-frequency power. Vacuum processing equipment. 5. At least a substrate is placed in a decompressible reaction vessel having a gas supply nozzle for supplying a source gas comprising a self-combustible gas and a supporting gas in the reaction vessel. A vacuum processing method for introducing a source gas containing a self-combustible gas and a supporting gas supplied from a pipe into the reaction vessel from the gas supply nozzle, and performing vacuum processing on the substrate in the reaction vessel. A vacuum processing method comprising shutting off the supply of the raw material gas based on a pressure detected by a pressure gauge provided immediately before including a connection portion of the pipe with the reaction vessel during the processing step. 6. The vacuum processing method according to claim 5, wherein the substrate is subjected to vacuum processing using the self-combustible gas and the combustion-supporting gas which have self-combustibility when mixed with each other at normal temperature and normal pressure. 7. The self-combustible gas and the combustion-supporting gas are supplied from outside by individually provided pipes, merge immediately before the reaction vessel, and then are supplied into the reaction vessel, and are provided immediately before the respective pipes merge. 7. The vacuum processing method according to claim 5, wherein the supply of the raw material gas is shut off by the provided valve. 8. A valve provided immediately before the junction of the individual pipes for supplying the self-combustible gas and the supporting gas, and a valve for the pipe for supplying the self-combustible gas when the self-combustible gas is not supplied. 8. The vacuum processing method according to claim 7, wherein, when the supporting gas is not supplied, the valves of the piping for supplying the supporting gas are closed. 9. The vacuum processing method according to claim 5, wherein the control for cutting off the supply of the supporting gas and the self-burning gas is automatically performed by a control device. 10. The method according to claim 5, wherein the vacuum processing method is a deposition film forming method for forming a deposition film by a plasma CVD method in which a source gas is decomposed by high-frequency power. Vacuum processing method.