JPS6381434A - Production of electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To provide superior positive chargeability by forming a carrier transferring layer made of amorphous silicon carbide (a-SiC) contg. a group IIIa element of the periodic table with gaseous C2H2, a gas contg. Si and a gas contg. the group IIIa element and by forming an a-SiC layer as a carrier generating layer on the carrier transferring layer in this order. CONSTITUTION:A reactive gas contg. gaseous C2H2, a gas contg. Si and 10<-6>-1mol% gas contg. a group IIIa element of the periodic table is decomposed by glow discharge to form a carrier transferring layer 5 made of a-SiC contg. the group IIIa element on an electrically conductive substrate 1. A reactive gas contg. gaseous C2H2 and a gas contg. Si is then decomposed by glow discharge to form a carrier generating layer 3a made of a-SiC on the carrier transferring layer 5. Thus, a durable sensitive body having superior positive chargeability and electrophotographic characteristics is obtd.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a method for producing an electrophotographic photoreceptor that has positive charging ability, maintains stable electrophotographic characteristics over a long period of time, and has excellent durability. It is related to.

[Prior art and its problems]

2. Description of the Related Art In recent years, the development of ultra-high speed copying machines, laser beam printers, etc. has been actively progressing, and as a result, electrophotographic photosensitive drums installed in these devices are required to have stable operating characteristics and durability.

In response to this demand, hydrogenated amorphous silicon is attracting attention because of its excellent wear resistance, heat resistance, pollution-free property, and photosensitivity characteristics.

As an electrophotographic photoreceptor made of such amorphous silicon (hereinafter abbreviated as a41), a laminated type photoreceptor as shown in FIG. 3 has been proposed.

That is, according to FIG. 3, an a-5t carrier injection blocking layer (2) and an a-5t carrier injection blocking layer (2) are formed on a conductive substrate (1) made of aluminum or the like.
A photoconductive layer (3) and a surface protection layer (4) are sequentially laminated, and this carrier injection blocking layer (2) is used to prevent carrier injection from the substrate (1) and to reduce residual potential. A highly hard material is used for the surface protective layer (4) to increase the durability of the photoreceptor.

However, according to this a-5i nausea photo, a-Siyt
, the dark resistivity of the i-electric layer (3) itself is 1011Ω・c
n+ or less, which increases the dark decay rate of this photoreceptor and makes it difficult to increase its own charging ability.As a result, when this photoreceptor is used for high-speed copying, it suffers from the optical memory effect. There is a problem in that the previous image is not completely removed and remains, and the previous image appears when the next image is formed (ghost phenomenon).

In order to solve this problem, a functionally separated photoreceptor as shown in FIG. 1 has been proposed.

That is, according to FIGS. 1 and 2, the basic structure is that a carrier transport layer (5) and a carrier generation Ji (3a) are sequentially laminated on a conductive substrate (1), and if desired, a conductive substrate (1) is laminated in sequence. A carrier injection blocking layer (2a) is provided between the substrate (1) and the carrier transport layer (5), or a surface protection layer (4) is provided on the carrier generation 1 (3a).

The carrier transport layer (5) is formed of a material having high dark resistance and carrier mobility, thereby providing a high-performance photoreceptor with excellent surface potential and photosensitivity and low residual potential.

For this carrier transport layer (5), it is recommended to use hydrogenated amorphous silicon carbide, which has high resistance, a wide band gap, and semiconductor properties.
This method has been proposed in, for example, the x9zo46 publication.

On the other hand, when using electrophotography with a photoreceptor charged to a negative polarity, the surface of the photoreceptor deteriorates due to ozone generated by corona discharge, reducing the electrophotographic characteristics and providing stable images over a long period of time. Therefore, it is desired that the photoreceptor be charged to a positive polarity.

Therefore, in the prior art mentioned above, the charging ability of positive polarity or negative polarity has not been sufficiently researched, and it is almost impossible to put it into practical use due to the electrophotographic characteristics with positive charging ability. The membrane speed is slow and impractical.

[Purpose of the invention]

Therefore, an object of the present invention is to provide a method for producing a durable electrophotographic photoreceptor having excellent positive chargeability and electrophotographic properties, that is, excellent dark decay and light decay properties.

Another object of the present invention is to improve the film formation rate.
An object of the present invention is to provide an inexpensive method for manufacturing an electrophotographic photoreceptor that is excellent in mass productivity.

Still another object of the present invention is to provide a method for manufacturing an electrophotographic photoreceptor suitable for use in a laser printer that has spectral sensitivity to wavelengths in the near-infrared region.

[Means for solving problems]

That is, according to the present invention, at least C, H2 gas, Si
Amorphous silicon carbide containing elements of group PmA of the periodic table is produced on a conductive substrate by glow discharge decomposition of a reaction gas containing gas containing gas and a gas containing elements of group A of the periodic table in an amount of 10-6 to 1 mole χ. Provided is a method for manufacturing an electrophotographic photoreceptor capable of being positively charged, characterized in that a carrier-generating layer is sequentially provided after forming a carrier-transporting layer consisting of the following.

Furthermore, according to the present invention, at least C, II2 gas,
Periodic table of Si-containing gas and 10-b to 1 mole χ
After a reactive gas containing a group A element is decomposed by glow discharge to form a transport layer of amorphous silicon carbide containing a group Ia element in the periodic table on a conductive substrate, at least a carbon ! +1. A positively chargeable electrophotographic photosensitive material, characterized in that a reactive gas consisting of a gas and a Si-containing gas is decomposed by glow discharge to sequentially provide a carrier generation layer made of amorphous silicon carbide on the carrier transport layer. A method of manufacturing a body is provided.

Furthermore, according to the present invention, at least C2H2 gas, Si
From amorphous silicon carbide containing a group IIIa element of the periodic table on a conductive substrate by glow discharge decomposition of a reaction gas containing a containing gas and a gas containing an element of group IIIa of the periodic table of 10-' to 1 mol χ After forming the carrier transport layer, a reactive gas containing at least C2H2 gas, a Si-containing gas, and a gas containing 1 mol% or less of Group IIIa elements of the periodic table is further decomposed by glow discharge to form a periodic layer on the carrier transport layer. A carrier generation layer made of amorphous silicon carbide containing an element of Group Ⅰ of the Periodic Table of the Periodic Table is provided, and the proportion of the gas containing the Group Ⅰ element of the Periodic Table of the amorphous silicon carbide generating gas at the time of forming the carrier generation layer is There is provided a method for producing an electrophotographic photoreceptor that can be positively charged, characterized in that the amount of charge is smaller than that when the carrier transport layer is formed.

The present invention will be explained in detail below.

The electrophotographic photoreceptor manufactured according to the present invention is a functionally separated laminated photoreceptor having the structure shown in FIGS. 1 and 2 as a basic structure.

According to the present invention, in the above structure, the carrier transport layer has amorphous silicon carbide (hereinafter abbreviated as a-SiC) as a main constituent element, and in order to terminate the dangling bond between Si and C, for example, t (or F, CI+Br,
Doping with halogen elements such as I, furthermore,
By containing the group a element within a predetermined range, it is possible to impart excellent positive charging ability as a photoreceptor. That is, by adding the Group IVa element of the periodic table, the carrier transport layer becomes a p-type semiconductor.

Taking the photoreceptor with the configuration shown in FIG. 1 as an example, its electrophotographic characteristics will be explained based on FIGS. 4(a) and (b).
Apply positive charging using charging means such as corona discharge (Figure 4 (
a)). Next, when exposure is performed, a carrier generation layer (5) is formed.
Electrons and holes are generated at
The total charge of the exposed area becomes zero. (Figure 4(b)
reference).

As mentioned above, the carrier transport layer of the electrophotographic photoreceptor in the present invention basically consists of a-5iC, but
Specifically, it is expressed by the following formula (1) % formula % (1) where 0.01≦X≦0.9, especially 0.05≦
By setting X≦0.5, the dark resistance is 1011CI
It can be greater than or equal to I+.

In addition, the elements of group ■a of the periodic table to be added are B, ^l
, Ga, and Im, with boron being particularly desirable. These are o, i to 10.000 ppm in the carrier transport layer,
Particularly, when the element is contained in an amount of 0.5 to 11,000 ppm, and the content is less than 0.1 ppm, there is no effect of adding an element of group 1111a of the periodic table, and the photoreceptor becomes negatively charged.

The content of II and halogen elements for terminating the a-5iC dangling bonds in the carrier transport layer is 5 to 40 atoms χ in the total composition, preferably 1O to 30 atoms χ
It is preferably within the range of .

Furthermore, the thickness of this carrier transport layer is 1 to 100 μm,
It is preferably set within the range of 5 to 50 μm,
If it is less than 1 .mu.-, the charge retention ability will be poor and the ghost phenomenon will become noticeable, and if it exceeds 100 .mu., the image resolution will deteriorate and the residual potential will tend to increase.

In the present invention, layers other than the carrier transport layer of the photoreceptor can be made of photoconductive materials that are well known per se, and the carrier generation layer can be made of polyvinyl carbazole, phthalocyanine, perylene, azo, or polycyclic quinone. organic semiconductors such as Se+ 5e-Te+ 5e-As, CdS,
ZnS, a-Si:H, a-SiGe:H, a-5iC
Inorganic semiconductors such as the following can be used.

Further, a carrier injection blocking Jiff (2a) is provided to prevent carrier injection into the carrier transport N (5), and is made of, for example, an organic material such as polyimide resin, 5iO
In addition to 1+SiO+A1□0++SiC+SiJ<+amorphous carbon, it is formed using an inorganic material in which the resistance value is controlled by doping a-5t or a-5iC with hydrogen, fluorine, oxygen, nitrogen, or the like. When using St-based or SiC-based elements, elements of group ■a of the periodic table such as boron and group
By adding a group 'a element in a range of 50 to 5000 ppm, carrier injection prevention can be further enhanced.

In addition, in the electrophotographic photoreceptor of the present invention, since the carrier transport layer having the composition described above can obtain a sufficiently large dark resistance, it is not necessary to form this carrier injection blocking layer. According to experiments repeatedly conducted by the present inventors, the dark resistivity of the carrier transport layer is 10'
It was confirmed that if the resistance was 3Ω·Cl11 or more, the electrophotographic photoreceptor could be put into practical use for -9 minutes without forming a carrier injection blocking layer.

In addition, various materials can be used for the surface protective layer as long as they themselves have high insulating properties, high corrosion resistance, and high hardness characteristics, such as inorganic materials similar to those used for the carrier injection blocking layer described above. or organic materials can be used, thereby increasing the durability and environmental resistance of the photoreceptor.

The thickness of each layer other than the carrier transport layer is 0.1 to 10 μm for the carrier injection blocking layer and 0.1 μm for the carrier generation layer.
It is desirable to set the surface insulating layer of 0.1 to 10 μm to 0.1 to 10 μm steel.

With the above-described configuration, the functionally separated electrophotographic photoreceptor of the present invention can advantageously make its surface positive polarized by corona discharge, and according to experiments conducted by the inventors, +600V
The above charging ability has been obtained, and as a result, a photoreceptor with no practical problems can be provided.

Next, the present inventors found that the positive charging ability could be further improved by selecting amorphous silicon carbide as a carrier generation layer compatible with the carrier transport layer having the composition described above.

The a-StC used is represented by the following formula (2) % formula % (2) where 0.01≦Y≦0.9, especially 0.05
It is desirable that ≦Y≦0.5.

In producing this carrier generation layer, a-SiC is also used.
As mentioned above, it is necessary to use 11 or a halogen element to terminate the dangling bonds in the material, and the content of these elements is within the range of 5 to 40 atoms χ, preferably 10 to 30 atoms χ in the total composition. All you have to do is make it look like this.

° Above, the photoreceptor in the present invention described above has a light wavelength of 300
However, according to the present invention, by adding Group IIIa elements of the periodic table to the carrier generation layer made of a-SiC, it is particularly sensitive to light in the near-infrared region. Sensitivity can be increased,
This allows application as a photoreceptor for laser printers. The amount of group 11ra elements of the periodic table in the carrier generation layer is 10. OOOppm or less, especially 11000p
Although it can be blended within a range of p or less, it is important that the amount is small compared to the addition amount of the element of group n[a of the periodic table] in the carrier transport layer. When the amount added to the carrier generation layer exceeds the amount added to the carrier transport layer, injection of excited carriers from the carrier generation layer to the carrier transport layer is inhibited, sensitivity decreases, and residual potential increases. This is because in the energy band between the carrier generation layer and carrier transport layer, the energy level of the carrier generation layer shifts to a higher energy side than that of the carrier transport layer, so when holes are injected into the carrier transport layer, there is an energy barrier at the interface. This is because it is formed.

The periodic table II [a group elements used include B, AI, Ga, In, etc. as in the case of the carrier transport layer, with B being particularly preferred.

According to the photoreceptor manufacturing method of the present invention, the main components of the inorganic photoreceptor include glow discharge decomposition method, ion blating method,
Thin film forming techniques such as reactive sputtering, vacuum evaporation, and CVO can be used.

For example, when forming the carrier transport layer as described above in the photoreceptor of the present invention, the glow discharge decomposition method is preferable, and the gaseous raw material used is 5tH4+5tzHth.
St-based gas such as +Stz ■ mouth, C114, CzIII
a, Czlb.

A C-based gas such as CJb or C+IIa may be used, and furthermore, Hz+He+Ne+Ar or the like may be used as a carrier gas. Gases containing Group IIIa elements of the periodic table include BJa, BFs+Al(CH3):+, Ga(C
H3)1. In(CH3)5. Ga(C1ls): + etc. 0 According to the experiments of the present inventors, when C2)1□ is used as the C-containing gas among the above-mentioned gases, an extremely high film formation rate (approximately 5 to 20 μvs/h) can be achieved. We found that it is possible to obtain Therefore, preferred reactive gases for forming the carrier transport layer include at least C2H2 gas, Si-containing gas, and gases from periodic table rIIa with a concentration of 10 to 6 to 1 mol χ.
Select a group element-containing gas. The specific composition of the reaction gas is (
It is desirable that the composition ratio (C, Hl gas:Si-containing gas) is 0.05:1 to 3:1.

According to the present invention, a-5iC is used as the carrier generation layer for the purpose of further improving the positive charging ability.
1□ gas and a Si-containing gas are used in the same composition ratio as when forming the carrier transport layer, and this reaction gas is decomposed by glow discharge to form on the carrier transport layer.

Furthermore, according to the present invention, a-SiC containing an element of group NLA of the periodic table is used as a carrier generation layer for the purpose of improving the spectral sensitivity to near-infrared light. , as in the case of forming the carrier transport layer, using a C2Hz gas, a Si-containing gas, and a gas containing an element of Group IIIa of the periodic table,
The gas containing Group A elements is blended in a proportion of 1 mol % or less, but for the reasons mentioned above, the proportion of the gas containing Group I elements of the Periodic Table in the reaction gas when forming the carrier generation layer is higher than that of the carrier transport layer. It is important that the amount is smaller than when it is formed.

When a carrier injection blocking layer or a surface protection layer is provided on the photoreceptor of the present invention as shown in FIG. 1 or 2, the material thereof may be SiC or a-Si:H.

When a-SiC, amorphous carbon, or a material doped with impurities is used, the films can be formed continuously using the same film forming apparatus, and the film forming time can be significantly shortened.

It should be noted that when an organic material is used in the N composition of the photoreceptor according to the present invention, it can be formed by any well-known means, and specifically, a polymeric material or an organic pigment,
It can be provided by a dipping method, a doctor blade method, etc. using a coating liquid in which an organic dye or the like is dissolved or dispersed in a volatile solvent.

Next, a capacitively coupled glow discharge decomposition device used in an embodiment of the present invention will be explained with reference to FIG.

In addition, as a gas containing elements of group 1ffa of the periodic table, 8□1
1. An example will be given using gas.

In the figure, 1st. Second. Third. 4th tank (6) (7)
(8) (9) are SiH4, C2H2, BJ, respectively.
a, II2 gas (38 ppm of B,!1. diluted in Ilz gas) is sealed, and 11 is also used as a carrier gas. These gases correspond to the first. Second. Third. Fourth regulating valve (10) (11) (
12) It is released by opening (13), and its flow rate is controlled by the mass flow controllers (14) (15) (
16) It is controlled by (17) and sent to the main pipe (1st).

Note that (19) is a stop valve.

The gas flowing through the main pipe (18) passes through the reaction tube (2).
A capacitively coupled discharge electrode (21) is installed inside this reaction tube, and the power applied to this is 50W to 3KW, and the frequency is IM.
Hz to 10 MHz is suitable. Inside the reaction tube (20), a cylindrical conductive substrate for film formation (22) made of aluminum is placed on a sample holding table (23).
This holding table (23) is rotatably driven by a motor (24), and the substrate (22) is heated to a temperature of about 50 to 400°C, preferably about 15°C by suitable heating means.
It is uniformly heated to a temperature of 0 to 300°C. Furthermore, the inside of the reaction tube (20) is kept in a high vacuum state B (discharge voltage 0.1 to 2.0 Torr) during the formation of an a-Si film or an a-SiC film.
r) is connected to the rotary pump (25) and the diffusion pump (26).

In the glow discharge decomposition device configured as above,
For example, a B-doped a-5iC film is used as a substrate (22
1.). Second. 3rd゜4th
tJi valve adjustment (10) (11) (12) (13) is opened and the 2nd and 3rd stages are opened. 4th tank (6) (7)
(8) From (9), SiH4 gas and CzHz, respectively.
Gas, BzHh gas and H2 gas are released, and the amount of these emissions is determined by the mass flow controller (10) (11) (1
2) Main pipe (18) regulated by (13)
The interior of the reaction tube (20) is in a vacuum state of 0.1 to 2.0 Torr, the substrate temperature is 50 to 400°C, and the capacitive discharge electrode (
21) 50W of high frequency power with a frequency of 1 to 10MHz
Coupled with the application of V to 3, a glow discharge occurs, the gas is decomposed, and a boron-containing a-5iC film is formed on the substrate at high speed.

〔Example〕

The present invention will be explained below with reference to Examples.

(Example 1) An aluminum drum for a substrate finished with a mirror finish using an ultra-precision lathe using a diamond cutting tool was cleaned by ultrasonic cleaning and steam cleaning using a solvent, and then dried.
It was installed in the reaction tube (20) of the capacitively coupled glow discharge decomposition apparatus shown in FIG.

Then, from the first tank (6), S i II s gas is fed for 100 seconds, from the second tank (7), czoz gas is fed for 20 seconds, and from the third tank (8), B2H & gas is fed for 2 seconds.
00sec, 300 UZ gas from the 4th tank (9)
Discharge at a flow rate of sccn+ and set the gas pressure to 0.4 Torr.
, a-5iC:H:
A carrier injection blocking layer made of B:N:O was formed.

Furthermore, carrier transport consisting of a-SiC doped with about 30 ppm of 8 under the conditions shown in Table 1 using the same equipment! (5) Carrier generation 1 consisting of , a-5i! (3a) and a surface protective layer (4) made of SiC were formed to obtain a photoreceptor having a thickness of 30.2 μm.

When the surface potential, dark decay, and light decay characteristics of the electrophotographic photoreceptor thus obtained were measured, the results shown in FIG. 6 were obtained. This is positively charged by +5.6KV corona discharge in the dark, and the change in surface potential with time in the dark and 6
The graph shows the change in surface potential over time immediately after irradiation with 50 in+ monochromatic light (exposure dose: 0.3 μm'/cm). In the figure, A is a dark decay curve and B is a light decay curve.

As is clear from Figure 6, the surface potential after 2 seconds is approximately 750
v, which is high enough for practical use, and as a result of optical attenuation, the surface potential becomes smaller instantaneously than exposure, and the residual potential also becomes significantly smaller.

(Example 2) In this example, a laminate consisting of three layers from (Example 1) except for the carrier injection blocking layer was molded, and the charging ability with both positive and negative electrodes was examined. Note that the film formation conditions and measurement conditions were the same as in (Example 1). The results are shown in FIGS. 7 and 8.

That is, Fig. 7 shows the dark decay curve and light decay curve when charged with +5.6 KV corona discharge, whereas Fig. 8 shows the dark decay curve and light decay curve when charged with -5.6 KV corona discharge. This is the case. As is clear from the results, positive charging increases the surface potential to +650V, which is sufficiently practical, whereas negative charging only provides a surface potential of about -55V.

(Example 3) Next, in the same manner as in the first example, a carrier injection blocking layer made of a-Si:B2Neo was formed using each of the gases of SiH4, fh+czHz and 81Hb at the flow rates shown in Table 2.
A carrier transport layer (5) made of a-SiC doped with ppra B, a carrier generation layer (3a) made of a-SiC, and a surface protection N (4) made of SiC were formed, and a photosensitive layer with a thickness of 30 μm was formed. I got a body.

The obtained photoreceptor was charged with +5.6 KV corona discharge in the same manner as in Example 1), and the dark attenuation and light attenuation were measured.
The results shown in Figure 9 were obtained.

As is clear from FIG. 9, excellent positive chargeability was exhibited.

(Example 4) Using 5IH41Hz+ C2Hi and thH& gas in the same manner as Example 1, a-5i at the flow rate shown in Table 3.
:B:N:O carrier injection blocking layer, approximately 30pp
Carrier transport 11(5) consisting of a-SiC doped with m B, a- doped with about 15 ppm+ B
A carrier generation JW (3a) made of SiC and a surface protection N (4) made of SiC were formed to obtain a photoreceptor having a thickness of 29.9 μm.

The obtained photoreceptor was charged by +5.6 KV corona discharge in the same manner as in Example 1), and the dark attenuation and light attenuation were measured, and the results shown in FIG. 10 were obtained.

In addition, when the spectral sensitivity of the photoreceptors manufactured in (Example 1), (Example 3), and (Example 4) was determined using light with a wavelength of 770r++a, (Example 1) was 0.18 cm"/erg (Example 3
) is 0.15cm”/erg, (Example 4) is 0.26c
A remarkable improvement in sensitivity was confirmed in the layer structure of m''/erg (Example 4).

〔Effect of the invention〕

As described above in detail, the method for producing an electrophotographic photoreceptor of the present invention uses at least CzHt gas, Si-containing gas, and gas containing an element of Group IIIa of the periodic table as a reactive gas, and a carrier transport layer containing a group IIIa element of the periodic table. Positive charging ability and electron It is possible to obtain an electrophotographic photoreceptor with excellent photographic properties, and the film formation rate can be extremely improved, so it is excellent in mass production. Furthermore, the stress for use in laser printers can be expanded.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the layer structure of a photoreceptor used in an embodiment of the present invention, FIG. 2 is a sectional view showing the layer structure of a photoreceptor used in another embodiment of the invention, and FIG. 4(a) and (b) are diagrams for explaining the electrophotographic characteristics of the electrophotographic photoreceptor of the present invention, and FIG. 5 is a cross-sectional view showing the general layer structure of the photoreceptor. Explanatory diagrams of the capacitively coupled glow discharge decomposition device used in the example, FIGS. 6 to 10 are diagrams showing dark attenuation curves and light attenuation curves, and FIGS. 6, 7, 9, FIG. 10 shows the photoreceptor of the present invention, and FIG.
The figure shows a comparative example. 1...Substrate 2.2a...Carrier injection blocking layer 3.3a...Carrier generation layer 4...Surface protection layer 5...Carrier transport layer Patent applicant (663) Kyocera Corporation Takao Kawamura

Claims (3)

[Claims] (1) Glow discharge decomposition of a reactive gas containing at least C_2H_2 gas, Si-containing gas, and gas containing 10^-^6 to 1 mol % of Group IIIa elements of the Periodic Table, and then depositing Group IIIa elements of the Periodic Table on a conductive substrate. 1. A method for manufacturing an electrophotographic photoreceptor capable of being positively charged, comprising forming a carrier transport layer made of amorphous silicon carbide containing a Group element, and then sequentially providing a carrier generation layer. (2) Glow-discharge decomposition of a reactive gas containing at least C_2H_2 gas, Si-containing gas, and gas containing 10^-^6 to 1 mol% of Group IIIa elements of the Periodic Table, and then depositing Group IIIa elements of the Periodic Table on a conductive substrate. After forming a carrier transport layer made of amorphous silicon carbide containing group elements, further glow discharge decomposition of a reaction gas made of at least C_2H_2 gas and Si-containing gas is performed to generate carriers made of amorphous silicon carbide on the carrier transport layer. A method for manufacturing an electrophotographic photoreceptor capable of being positively charged, characterized by sequentially providing layers. (3) Glow discharge decomposition of a reactive gas containing at least C_2H_2 gas, Si-containing gas, and gas containing 10^-^6 to 1 mol % of Group IIIa elements of the Periodic Table, and then depositing Group IIIa elements of the Periodic Table on a conductive substrate. After forming a carrier transport layer made of amorphous silicon carbide containing group elements, further glow discharge decomposition of a reactive gas containing at least C_2H_2 gas, Si-containing gas, and gas containing 1 mol % or less of Group IIIa elements of the periodic table is performed. a carrier generation layer made of amorphous silicon carbide containing a Group IIIa element of the periodic table is provided on the carrier transport layer;
Electrophotographic photosensitive material capable of being positively charged, characterized in that the ratio of a gas containing a Group III element of the periodic table in the amorphous silicon carbide generating gas during the formation of the carrier generation layer is smaller than that during the formation of the carrier transport layer. How the body is manufactured.