JPS616276A - Plasma CVD equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention [Technical Field] The present invention relates to the production of electrophotographic photoreceptor drums, for example, by depositing a film of amorphous silicon or the like on the surface of a cylindrical substrate such as a drum using plasma CVD technology. Regarding a plasma CVD device that can continuously produce, in particular, a plasma CVD device that can uniformly deposit a 7-molyphasic silicon film on the drum surface by appropriately processing the raw material gas.
It is related to the device.

] Prior art 1 This type of device has a structure similar to a conventional capacitively coupled plasma CVD device if classified based on the electrode arrangement method of the plasma CVD device. When applied to a commercial plasma CVD apparatus, the cathode electrode and the anode electrode (drum) are arranged concentrically and rigidly, which limits the number of drums that can be accommodated and complicates the apparatus structure.

Therefore, in consideration of the above-mentioned problems, in order to obtain a mass production device for electrophotographic photoreceptor drums that mainly uses amorphous silicon photoreceptor material, the complicated device structure such as the conventional example described in -L was significantly reduced. By simplifying the system, increasing the number of drums that can be stored, and improving the electrode arrangement method and shape, we have made it possible to advantageously mass-produce electrophotographic drums and perform high-speed film formation, which was difficult with conventional equipment. A device was proposed.

FIG. 1 shows such a plasma CVD apparatus, and in the figure 1
Reference numeral 5 denotes a drum as a cylindrical base body, which is an aluminum substrate formed into a drum shape so as to form an amorphous silicon film on its surface.

1 is a heating chamber for heating the drum, 2 is a reaction chamber provided following the heating chamber 1 and for forming an amorphous silicon film on the surface of the drum 15 by plasma CVD, and 3 is a reaction chamber in the reaction chamber 2. A cooling chamber is provided next to the drum for cooling the drum after film formation. These chambers 1.2
and 3 have an airtight structure. 6 is multiple drums 1
5 are rotated around their axes, and held upright so that their central axes are on the same plane and parallel to each other, and further, using a holding frame equipped with a drum rotation conveyance mechanism. be.

A pair of heaters 4 are arranged in the heating chamber 1 along the continuous direction of the chambers 1, 2 and 3.

The pair of heaters 4 are arranged upright so as to be parallel to each other, and heat a drum 15 arranged between them so that the arrangement direction is parallel to the heaters 4. Reference numeral 5 denotes an exhaust system provided on one side wall of each chamber and equipped with a filter and baffle for keeping each chamber in a vacuum. A pair of flat electrodes 7 serve as cathode electrodes, and are arranged upright in the reaction chamber 2 so as to be parallel to each other. This pair of electrodes 7 has a double structure for supplying raw material gas,
The drum 15 has a large number of holes over its entire inner surface that ejects gas toward the drum 15, which is arranged so that its arrangement direction is parallel to the electrodes 7, and is further heated by a heater. 8
is a raw material gas supply pipe connected to the outside of the flat electrode 7 for supplying raw material gas into the double structure of the electrode 7;
8 is a power source for supplying high frequency power to the electrode 7 via the pipe 8; 10 is a drum 15 held by the holding frame 6;
This is the ground for using as an anode electrode.

A pair of cooling plates 11 are arranged upright in the cooling chamber 3 so as to be parallel to each other. A pair of cooling plates 1
1 has a refrigerant flow path for water or the like inside to cool the drum 15 between which the film formation has been completed. 12 is a refrigerant such as water to be supplied into the cooling plate 11; 13 is a gate Φ which isolates each chamber 1, 2, and 3 and is controlled to be open when the drum 15 moves together with the holding frame 6; A valve 14 is a leak valve provided in the exhaust system 5 of the heating chamber 1 and the cooling chamber 3 to return each chamber 1 and 3 to the atmosphere.

The drum 15 fixed to the holding frame 6 passes through the gate valve 13 at the left end in FIG. Meanwhile, it is heated by the heater 4. The heated drum 15 passes through the gate valve 13 between the two chambers 1 and 2, and is transferred to the reaction chamber 2, which is kept in vacuum by the exhaust system 5, into the holding frame 8.
The drum 15 that entered the reaction chamber 2 is connected to the ground l.
0 to form an anode electrode for a pair of electrodes 7 serving as cathode electrodes connected to a high frequency power source 8. An amorphous silicon film is formed on the surface of the drum 15, which forms an electric field with the electrode 7 and is heated by a heater, by decomposing a raw material gas such as silane sent from the raw material gas supply pipe 8 in plasma. The drum 15 on which the film has been formed passes through the gate valve 13 between the reaction chamber 2 and the cooling chamber 3, enters the cooling chamber 3 kept in vacuum by the exhaust system 5, and is pumped with refrigerant through the cooling plate 11. The gate valve 13 at the right end in FIG.
The vapor deposition process is completed by passing through the inside and being taken out of the cooling chamber 3.

However, the plasma CVD apparatus having the above configuration has the following drawbacks. That is, FIG. 2 shows a cross section of the cooling chamber 2, and as indicated by arrows in the figure, the raw material gas is directed toward the drum 15 from the gas jet holes 7^ formed over the entire surface inside the flat electrode 7. The raw material gas ejected from the flat electrode 7 on the right side in Figure 0 contacts mainly the right half circumference of the drum 15, and then passes around the flat electrode 7 on the left side and is exhausted to the exhaust system 5. is,
On the other hand, the raw material gas ejected from the plate-like seven electrodes on the left side of the figure contacts mainly the left half-periphery of the drum 15 and is exhausted to the exhaust system 5 through the periphery of the left-side plate-like electrode 7.

In this way, in the reaction chamber 2, as shown in FIG. Gas etc. tend to stagnate, as a result,
The density of the raw material gas tends to be non-uniform around the drum 15, and therefore the thickness and quality of the amorphous silicon film obtained on the surface of the drum 15 tends to be non-uniform.

On the other hand, the flat cathode electrode 7 serves both as an electrode and as a gas ejection stage f, and therefore has a complicated structure, which may cause abnormal discharge at the gas ejection holes.

The first aspect of the present invention is to solve the above-mentioned problems and to provide a drum, etc., which forms an appropriate flow of raw material gas and has a film of amorphous silicon or the like on its surface with a uniform film thickness and film quality. An object of the present invention is to provide a plasma CVD apparatus capable of obtaining a cylindrical substrate.

[Example 1] Fig. 3 is a plan view of a plasma CVD apparatus according to an embodiment of the present invention, Fig. 4 is a perspective view of the main parts of the apparatus, and Fig. 5 is a sectional view of the main parts of the apparatus. It is.

The plasma CVD apparatus according to the present invention has the same configuration as the plasma CVD apparatus shown in FIG. 1 except for the electrodes in the reaction chamber and the structure for supplying and exhausting raw material gas, so the following will mainly explain one reaction chamber. explain.

That is, as shown in FIGS. 3 and 4, in the reaction chamber 21 of the plasma CVD apparatus according to the present invention, a pair of flat electrodes 22 and 25 with flat insides are provided, similar to the conventional flat electrode 7. The pair of flat electrodes 22 and 25 are heated by a heater. Among the pair of flat electrodes 22 and 25, one electrode 22 has a double structure for supplying raw material gas, like the conventional electrode 7, and has numerous holes 23 for gas injection over the entire inner surface. . The other electrode 25 is flat without having a gas ejection hole inside thereof, and is connected to the high frequency power source 8 via a connecting means 25^, and serves as one cathode electrode.

A raw material gas supply pipe 24 for supplying raw material gas into the double structure is connected to the outside of one flat electrode 22, and the electrode 22 is connected to a high frequency power source 8 via this pipe 24. This is the other cathode electrode.

At the -L end and the lower end of the other flat electrode 25, a pair of exhaust pipes 2B are provided, respectively, close to and parallel to this, that is, parallel to the arrangement direction of the drums 15. The length of the exhaust pipe 2B is approximately the same as the length of the flat electrode 25.

A plurality of gas suction holes 27 are formed in the exhaust pipe 26 along its length. The raw material gas supply pipe 24 is connected to a raw material gas supply 1viS (not shown), and the exhaust pipe 2B is connected to a pipe 2[I] connected to an exhaust device (not shown).
B is communicating.

The drum 15 is grounded and serves as an anode electrode.

The operation of the plasma CVD apparatus of the present invention having the above configuration will be explained next. As shown by arrows in FIGS. 4 and 5, the raw material gas ejected from the inner hole 23 of one electrode 22 into the reaction chamber 21 toward the drum 15 flows between the pair of flat electrodes 22 and 25. It flows through the space perpendicular to the axial direction of the drum 15 and passes around the drum 15, and then,
The gas is sucked into the holes 27 of the exhaust pipe 2B at the upper and lower ends of the other electrode 25 and exhausted to the outside of the reaction chamber 21. In this way, the raw material gas is ejected from the hole 23 of the electrode 22 and is spread all around the drum 15 in a direction perpendicular to its axis until it contributes to the formation of an amorphous silicon film on the surface of the drum 15. A smooth flow is formed without stagnation, and then the exhaust pipe 26
is exhausted to the outside of the reaction chamber 21.

Therefore, the gas density around the drum 15 becomes uniform throughout, and an amorphous silicon film with uniform thickness and quality is formed on the surface of the drum 15.

Note that by appropriately setting the spacing between the positions and the number of holes 27 for sucking the raw material gas, the gas density in the arrangement direction of the drums 15 can be appropriately controlled.
Therefore, the decomposition efficiency of the source gas in the same arrangement direction can be efficiently controlled.

The processing of the drum 15 in the heating chamber 1 and the cooling chamber 3 is the same as in the conventional case.

Furthermore, in the above embodiment, the pair of electrodes 22 and 25 were both connected to the high frequency power source 8 to serve as cathode electrodes, but it is also possible to use one of them as a cathode electrode and the other to be grounded without being connected to the high frequency power source 9. Alternatively, it may be used as an anode electrode (the drum 15 is grounded in either case).

[Effects] As explained above, according to the present invention, it is possible to efficiently obtain a cylindrical substrate having a film of amorphous silicon or the like on its surface that has uniform film thickness and film quality and excellent electrical properties. . Further, according to the present invention, the gas density distribution in the arrangement direction of the cylindrical substrates can be appropriately controlled.

Furthermore, according to the present invention, a simple parallel plate electrode structure is sufficient.

A schematic plan view of a plasma CvD apparatus, FIG. 2 is a longitudinal sectional view of a reaction chamber in the apparatus, and FIG. 3 is a plasma CvD apparatus according to the present invention for manufacturing an electrophotographic photosensitive drum.
FIG. 4 is a plan view showing an embodiment of the VD device, FIG. 4 is a perspective view showing the main parts of the device, and FIG. 5 is a longitudinal sectional view of a reaction chamber in the device.

15...Drums, 21... reaction chamber, 22.25... flat electrode, 23... hole for ejecting raw material gas, 24... Raw material gas supply pipe, 26...exhaust pipe, 27... Hole for sucking raw material gas.

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Claims (1)

[Claims] A pair of parallel plate electrodes arranged parallel to each other and having a raw material gas ejection part formed inside one of them; substrate holding means for arranging a plurality of cylindrical substrates between the pair of parallel plate electrodes so that
a raw material gas exhaust means arranged near the periphery of the other of the pair of electrodes so that the raw material gas suction part is located along the arrangement direction of the plurality of cylindrical substrates arranged between the pair of parallel plate electrodes; A plasma CVD apparatus characterized by: