JPS6243650A - Electrophotographic sensitive body - Google Patents

Abstract

PURPOSE:To prevent the deterioration of a photosensitive body by corona impression so as to extend the life of the photosensitive body and to upgrade printing resistance so as to prevent the character flow and toner flow during printing by incorporating specific impurity atoms into an a-Si barrier layer on a conductive substrate. CONSTITUTION:The impurity atoms consisting of the group III element are incorporated into the barrier layer of the photosensitive body constituted by successively laminating the barrier layer consisting of a-Si, photosensitive layer consisting of a-Si and protective layer consisting of a diamond-like carbon film on the conductive substrate. B is preferable as such group III element and is incorporated therein a 5X10<-5>-2.0X10<-3> ratio by the number of atom of Si. The group III or/and group V element, for example, B or/and P are preferably added to the diamond-like carbon film of the protective layer. Such photosensitive body is free from a decrease in the receptive potential even when subjected continuously to the repetition of the corona impression for a long period of time. The semi-permanent use is thus made possible and such is advantageous for maintenance. Since the impression of a high voltage to the photosensitive body is possible, uneven copying hardly arises in a copying stage and the photosensitive body having the long life is obtd.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to an electrophotographic photoreceptor, and more specifically, it relates to an amorphous photoreceptor that does not cause corona deterioration and staining when applied with corona and has a long lifespan. This invention relates to a silicon electrophotographic photoreceptor.

(Prior Art) Conventionally, electrophotographic photoreceptors include Se, 5e-Te,
Alternatively, 5e-AS systems, CdS systems, 2nO systems, etc. have been used. CdS has basic defects such as poor reproduction performance under high humidity and being a toxic substance. In addition, Se-based materials are similarly harmful substances and have poor heat resistance.If the temperature of the photoconductor itself rises above 40'C, the copying function will be poor and the hardness will be low, leaving problems with wear resistance. Printing durability is not sufficient.

Therefore, in recent years, amorphous silicon photoreceptors have attracted attention because of their non-polluting properties, high sensitivity, high hardness, and abrasion resistance (long life). By the way, as is well known in the electrophotographic process, there is an electrostatic charge application process using corona discharge, an exposure process,
There is a toner transfer process and a cleaning process, and even if any one of them is defective, a long life cannot be achieved.

Among these, amorphous silicon photoreceptors suffer from serious problems such as corona deterioration caused by exposure to corona, which prevents the desired charge from being applied to the photoreceptor surface and causes toner flow and defects during development, making development difficult. The reality is that there remains. Various studies have been carried out to solve these problems, and for example, as described in Japanese Patent Application Laid-Open No. 60-61761M, there is a method of forming a diamond-like carbon film made of carbon and hydrogen as a protective layer on an amorphous silicon photosensitive layer. However, in this case, it is certainly effective against corona irradiation because it has a protective film, but if printing is repeated for a long time, the amount of charge on the surface of the photoreceptor gradually decreases, making it impossible to maintain the receptive potential necessary for printing. However, it has the serious drawback that it induces streaks and toner flow, and as a result, long life cannot be obtained.

(Problems to be Solved by the Invention) It is an object of the present invention to eliminate the drawbacks of the prior art and to provide an amorphous silicon electrophotographic device that has high printing durability and has a long life that does not cause cursive lines or toner flow during printing. The purpose is to provide a photoreceptor.

(Means for Solving the Problems) The present invention is an amorphous silicon film formed by sequentially laminating a barrier layer made of amorphous silicon, a photosensitive layer made of amorphous silicon, and a protective layer made of a diamond-like carbon film on a conductive substrate. The electrophotographic photoreceptor is characterized in that the barrier layer contains an impurity atom consisting of an element of group Ⅰ of the periodic table.

The conductive substrate according to the present invention has an electrical resistivity of 1×10
Refers to a substrate composed of a metal, a metal oxide, or a grained material with a resistance of 3 Ω・cm or less, and includes A1, Fe,
, Ni5Cr, etc., or alloys such as stainless steel with an electrical resistivity of 1 Ω·cm or less are preferable.

More preferred is AI. Of course, among these metals,
A small amount of nonmetallic elements may also be included. The thickness of the substrate is not particularly limited and can range from several tens of centimeters to several centimeters. Furthermore, it is preferable for the surface shape of the substrate to be mirror-like as much as possible in view of the characteristics of the photoreceptor.

In the present invention, a photosensitive layer made of amorphous silicon (hereinafter referred to as an amorphous silicon photosensitive layer) is a photosensitive layer that is mainly composed of silicon atoms, hydrogen atoms, and/or fluorine atoms, and has an amorphous structure. However, it also refers to something that causes changes in electrical resistance due to differences in brightness and darkness of light. Other atoms into the photosensitive layer, such as B, O, N S
There are no particular restrictions on the inclusion of Ca, C, Ge, etc. as impurity atoms, but the photosensitive layer must contain at least 10% of Si atoms and have photoconductivity. is desirable. Further, the amorphous silicon photosensitive layer in the present invention may be a layer formed by laminating amorphous silicon layers appropriately containing these impurity atoms or amorphous silicon layers not containing these impurity atoms in an appropriate combination.

Furthermore, an amorphous silicon photosensitive layer containing a small amount of microcrystalline silicon can also be used without problems.

The thickness of the amorphous silicon photosensitive layer is appropriately determined in consideration of the relationship with other factors (the performance of the copying machine, the structure of the photoreceptor, etc.), and is usually preferably in the range of 10 μm to 50 μm. The method for producing the amorphous silicon photosensitive layer is not particularly limited, and may be any of vapor deposition methods, plasma CVD methods, sputtering methods, normal pressure CVD methods, photo-CVD methods, and the like.

Among these, the plasma CVD method is preferable because impurities can be easily controlled. The plasma source used here may be direct current plasma or alternating current plasma, but it is preferable to use high frequency (10KH2 to 14HH2) plasma from the viewpoint of decomposition of the raw material gas. Further, as the reaction residue, silane (SiH4), disilane (Si2H6), higher order silane, etc. can be preferably used.

In the present invention, the protective layer laminated on the photosensitive layer refers to a layer or film that is laminated on the amorphous silicon photosensitive layer and serves to protect the photosensitive layer from various stimulation effects caused by the electrophotographic process. , the joint surface of these two layers is
They may be chemically bonded or physically bonded. The protective layer used in the present invention is a diamond-like carbon film composed of main constituent atoms, carbon, hydrogen, and/or fluorine, and it is important that the main constituent atoms account for 90% or more of the total number of constituent atoms. It is.

A case where carbon, hydrogen, and fluorine are sequentially increased during the lamination of an amorphous silicon photosensitive layer so that the main constituent atoms eventually constitute 90% or more of the constituent atoms also corresponds to the cold insulation layer in the present invention. The main purpose of the protective layer is to protect the amorphous silicon photosensitive layer from stimulation by corona irradiation and prevent corona deterioration, but it can also protect against abrasion.

The diamond-like carbon layer referred to in the present invention is mainly composed of carbon, hydrogen, and fluorine atoms, and the main constituent atoms (carbon, hydrogen, and fluorine) making up the layer account for 90% of the total number of constituent atoms. % or more.

The ratio of hydrogen and fluorine to carbon, which is the number of main constituent atoms, is 0.
Preferably, it is greater than 1 and less than or equal to 0.4. If the ratio υ1 of the number of main constituent atoms to the total number of constituent atoms is less than 90%, the effect against corona irradiation will be weak, which is not good.

Generally speaking, in the present invention, it is more preferable to add an element consisting of a Group I element and/or a Group V element in the periodic table as an impurity atom to the protective layer.

In the case of group (3), boron (B) or aluminum (A1) is preferable, and boron (A1) is more preferable.
B). In addition, as group V elements, arsenic (AS),
Nitrogen (N) and phosphorus (P) are preferable because doping can be controlled relatively easily, and phosphorus (P) is more preferable because of the characteristics of the film.

When adding impurity atoms to the film, the content is preferably such that the atomic ratio to carbon in the film is in the range of 1x10-7 to 8x10-4, more preferably 2x10-4x10-4.
It is.

Other impurities include oxygen and nitrogen that are mixed in at a minute amount during film formation, but if the amount is minute, there is no problem with 1).

The structure of the diamond-like carbon layer may be a crystalline structure, an amorphous structure, or a structure containing a small amount of crystals in the amorphous structure, but an amorphous structure is preferable from the viewpoint of ease of molding. In the amorphous structure, a 3p3 electron configuration (carbon single bond) is preferred in the carbon bond state, but a trace amount of Sp2 electron configuration (carbon double bond) may be included.

However, from the viewpoint of obtaining a high resistance value, it is more preferable to have fewer sp2 electron configurations.

Such a diamond-like carbon layer is produced using hydrocarbon or solid carbon as the main raw material, using a chemical vapor deposition (CVD) method,
Alternatively, it is formed in a reduced pressure container by a plasma CVD method, an ion beam evaporation method, or the like.

That is, sputtering is performed by introducing an inert gas and a reactive gas, such as hydrogen gas, hydrogen gas and deborane (B2 H6) gas, or hydrogen gas and phosphine (PH3> gas) into a vacuum vessel using solid carbon as a target. how to,
Alternatively, there is a reactive vapor deposition method in which carbon or a raw material containing carbon and hydrogen is used as an evaporation source in a vacuum vessel, and hydrogen, deborane (82H6), or phosphine (PH3) gas is used as a reactive gas. In the case of the reactive deposition method, the method of heating the evaporation source may be resistance heating or electron beam heating.

Another method is to mix a gas composed of hydrocarbons and hydrogen gas as a carrier gas, or hydrogen gas and 82 H6 gas as a doping gas, or PH3 gas, and introduce the mixture into a vacuum container, and then use direct current or alternating current. There is a so-called plasma CVD method in which a plasma is generated by applying a plasma to an electrode placed in a reduced pressure container.

For forming the protective layer, the plasma CVD method is more preferable from the viewpoint of equipment and equipment.In this case, the temperature of the substrate is lowered to 1
Diamond-like carbon can be obtained by appropriately selecting a temperature between 00 and 200°C. The raw material gas includes saturated hydrocarbons and unsaturated hydrocarbons, but ethylene, methane, and acetylene are preferable from the viewpoint of gas decomposability.

As the solid carbon raw material, graphite, grady carbon, etc. are used. Whether the protective layer is diamond-like carbon or not depends on the energy loss and bonding state of carbon in the protective layer.
This can be confirmed by measuring with a spectrum analyzer (E, L, S,). That is, 5 in the spectrum
This can be confirmed by whether an absorption peak appears at ~7 eV (sp2 electron configuration).

In addition, from the infrared absorption spectrum, depending on the presence or absence of absorption near 2920 cm''l, single bonded carbon bonded to hydrogen (
The presence of C-H) can be determined.

To roughly confirm the crystalline state, the amorphous state can be confirmed by measuring a Raman spectrum. That is, strong absorption appears near 1580 cm', and 1350 cm'
This is determined from the appearance of a weak peak in layer m-''.

The thickness of the protective layer is preferably in the range of 100 μm to 20 μm,
Furthermore, the number is preferably 1'50 to 5,000 people, more preferably 200 to 2,000 people. 100
A thickness less than that of a human being is not preferable because it becomes weak against long-term continuous corona irradiation in terms of resistance to corona application, light irradiation, and repeated abrasion in the electrophotographic process. When the thickness of the protective layer exceeds 20 μm, the film thickness becomes thick, and the light transmittance decreases, which deteriorates the photosensitivity of the photoreceptor, which is not preferable.

In the present invention, the barrier layer is made of amorphous silicon and contains an element of Group 1 of the periodic table as an impurity atom, and is provided between the conductive substrate and the amorphous silicon photosensitive layer. Amorphous silicon is mainly composed of silicon atoms, hydrogen atoms, and/or fluorine atoms, and has an amorphous structure. However, the layer may contain a small amount of microcrystalline silicon. As impurity atoms in amorphous silicon,
Boron (B), aluminum (A1), gallium (Ga
) is preferred, and boron (B) is more preferred. The amount of boron (B) is preferably in the range of 5.times.10@-5 to 2.0.times.10@-3 in terms of atomic ratio to silicon atoms.

More preferably, it is in the range of 5 x 10"5 to 8 x 10-4. If it is less than 5 x 10-5, the long-term corona resistance will be poor and the acceptance potential may decrease.2.0 x 10
If the content exceeds -3, although long-term corona resistance is strong, the original acceptance potential may be lowered.

The thickness of the barrier layer is not particularly limited, but
If it is thin, the corona resistance will be weak, and if it is thick, the acceptance potential will be low, so the preferred film thickness is 0.2
~1.0μm, more preferably 0.2~0.5μm
It is m.

As a film forming method, a method similar to the method of forming an amorphous silicon photosensitive layer is adopted.

Regarding the layer division, the barrier layer and the photosensitive layer may be formed continuously (in this case, while changing the amount of impurity gas added), or may be formed intermittently.

When a barrier layer is deposited on a conductive substrate, it is preferable to perform a bombardment treatment with Ar ions immediately before film deposition in view of the properties of the photoreceptor, particularly the charging ability.

In the present invention, the layer structure formed on the conductive substrate is not necessarily limited to three layers; for example, between the barrier layer and the photosensitive layer, or between the photosensitive layer and the protective layer, germanium (Ge), Alternatively, a four-layer structure may be provided by providing a layer containing tin (sn) or the like.

(Function of the invention) The electrophotographic photoreceptor of the present invention has a barrier layer that is listed in the periodic table.
It is composed of amorphous silicon that contains group elements as impurities, and is laminated with a protective layer consisting of an amorphous silicon photosensitive layer and a diamond-like carbon film that protects the photosensitive layer from corona deterioration, so that corona stimulation of the surface layer is avoided. In order to protect the photosensitive layer from the electroconductive substrate (electrode) and prevent the injection of various impurity ions and electrons from the conductive substrate (electrode), the first son was continuously exposed to corona light q41. l
Even if I3 and electrophotography are repeated, clear images can be obtained without any decrease in acceptance potential.

Since an amorphous silicon photoreceptor without a barrier layer (conductive substrate/'amorphous silicon photoreceptor/diamond-like carbon layer) does not have an electron barrier layer (barrier layer), the surface of the photoreceptor does not reach the surface in the dark. When a positive impression is applied, electrons generated on the surface of the substrate due to electrostatic induction are easily injected into the photosensitive layer and recombined on the surface of the photosensitive member near the layer, lowering the acceptance potential. Moreover, if (corona application - [16 attenuation - bright attenuation)] is repeated, electron injection from the substrate side becomes more likely to occur, and therefore, if this is repeated for 1 time, the acceptance potential will gradually decrease. It can be considered as a thing.

For this reason, the present inventors have investigated various barrier layers. 5i02, when a SiOx film is used as a barrier layer, the acceptance potential increases, but if corona application is repeated, the residual potential gradually increases and, moreover, the acceptance potential decreases. This is considered to be because impurities in the barrier layer deposited on the substrate side diffused into the photosensitive layer.

On the other hand, when the barrier layer was formed of an amorphous silicon film containing boron (B), for example, the acceptance potential did not decrease at all even after repeated corona cycles, but surprisingly showed a tendency to increase slightly with repeated cycles. Although no clear reasoning can be given, this may be due to impurities in the barrier layer (
This is thought to be because boron (B3) diffused into the photosensitive layer and the photosensitive layer changed into a hole-rich layer. However, even if such a phenomenon occurs, other photosensitive characteristics do not change at all.

In addition, the protective layer has a carbon bond similar to that of a diamond structure, so its bond energy is high, and it is doped with impurities to increase hardness and electrical resistance, so it perfectly protects the photoreceptor from the corona applied to the surface. There is.

In this way, the amorphous silicon photoreceptor of the present invention, which has a barrier layer on the conductive substrate side that utilizes impurity diffusion inversely and provides an effective protective layer, is an ideal photoreceptor with a long life. It is.

[Effects of the Invention] The electrophotographic photoreceptor of the present invention has barrier properties that are as low as 1I of the periodic table.
Since it is made of amorphous silicon containing impurity atoms consisting of the I b'i element and is provided with a protective layer made of diamond-backed carbon, the acceptance potential does not drop at all even if corona application is repeated continuously for a long period of time. ! Previously, the photosensitive drum, which is the heart of a copying machine, had to be replaced every time tens of thousands of copies were made, but now it can be used semi-permanently, which is advantageous in terms of maintenance costs. .

Since it does not cause corona deterioration, it is possible to apply a higher voltage than conventional photoreceptors, and it can be expected to have effects such as less unevenness in copying during the copying process.

The present invention will be explained below with reference to Examples. Note that the measurement items in the examples were measured by the following methods.

(Method of measuring characteristics, evaluation criteria) (1) Thickness of each layer: IMS- manufactured by CAMECA (French painting)
Secondary ion mass spectrometry (S
The thickness of each layer was determined by conducting elemental analysis in the depth direction from the surface of the photoreceptor using IMS).

(2) Charging ability of electrophotographic photoreceptor; applied polarity (+), voltage 6. Qkv, application time: 6°0 seconds, darkening time: 5.0 seconds, exposure time: 10 seconds. The exposure conditions were a tungsten lamp (color temperature: 2856°) and 2.0 Iux of light. Measurement atmosphere is 23±1°C160
%R was set at 11. The charging ability was defined as the value obtained by dividing the surface potential 6 seconds after the start of application by the thickness of the photosensitive layer.

(3) Identification of diamond-like carbon layer; 31 of (1)
) The atomic ratio of carbon and hydrogen was determined from the measurement results of Is.

Impurities (boron: (8),
Also for films to which phosphorus (P) was added, the atomic ratio of boron, phosphorus, etc. to carbon was determined in the same manner as in (1). Rehabilitation and correction in this case were carried out using a known sample in which boron ions were implanted into a diamond-like carbon film.

Structural analysis was performed by Raman spectroscopy (confirmation of crystalline and amorphous states).

The bonding state of carbon was measured by S, (energy loss spectrum analyzer).

The Raman spectrum measurement device is U-100
The measurement was carried out using a type 0 (manufactured by Jobin-Yuon, France) and an argon ion laser (wavelength 5145). Further, E, L, and S were measured using Escalab type 5 (manufactured by Vacuum Generator Scientific, UK) with incident electron energy of 1200 eV, analyzer, CAE mode, and pass energy of 20 ev.

In Raman spectroscopy, the diamond-like carbon layer is
It has a strong band peak at 1550-1600 cm',
This was confirmed by showing a weak peak near 1350 Cm-1.

In terms of E, L, and S odors, the diamond-like carbon layer does not show a peak at 5 to 7 eV, so the bonding state of carbon is not a double bond, a triple bond, but a 3p - double bond.
It can be seen that it has 3 hybrid orbitals. In addition, the C-C bond is 2000cm゛1.2500 according to the infrared absorption spectrum.
This can be confirmed by whether strong absorption appears in cm-'.

(4) Measurement of infrared absorption spectrum: Measurement was performed using a sample in which a film was deposited on a silicon wafer substrate using a micro-transmission infrared absorption spectrum ((FT-IR), manufactured by DigiLab (USA)).

(5) Measurement of impurities (B) in barrier layer: (1)
5I) From the measurement results of Is, the atomic ratio of boron (B) to silicon atoms was determined.

[Examples 1 to 9] Table 1 shows experiments in which the film-forming conditions for the photosensitive layer and the protective layer were kept constant, and the film-forming conditions for the barrier layer (impurity doping) were changed.

First, in Examples 1 to 9, slide glass/AI vapor deposited film (
A substrate with a diameter of about 0.6 μm) was placed in a plasma CVDIJ (with a flat plate bipolar electrode arrangement), and after being evacuated to 1X10-6 Torr or less, a gas was passed through it and bombarded with ions (Ar gas: 5,03 CCI). (, substrate temperature;
15~20″C, gas pressure: 0.05 Torr, high frequency (
13, 56) 111Z) Output; 50W, processing time; 10
minutes). Next, the barrier layer of the amorphous silicon film was formed to a thickness of 5000 angstroms by adjusting the time under the following conditions.

The conditions at this time are raw material gas (10vo1%3iH4in
H2 gas) and impurity gas (401) 911182 He
The flow rate of 1nH2 gas) was changed as shown in Table 1, and the other conditions were: high frequency (13,568H7) output; 60W
, gas pressure of 0.9 Torr, and substrate temperature of 200°C. At this time, a film was also deposited on a single crystal silicon wafer (P type, electrical resistance 10 to 20 Ω-cm, thickness: 525 μm), and the atomic ratio of boron (B) to the number of 3i atoms was measured using 5I)Is. , the content of boron atoms was measured. The results are shown in Table 1.

Next, a 15.0 μm thick photosensitive layer was laminated on the substrate using the above sample as a substrate and adjusting the time under the following conditions.

The conditions are “IQV01%3i1-14inf-12cas: 25SCC)I, 40p1)m B2 H61nH
2 gases: 2.9SCCH1 Substrate temperature: 200'C, gas pressure: 0°95Torr, high frequency (13, 568111)
It was set to 60W.

Next, by changing the raw material gas and using the above sample as a substrate, a protective layer was laminated on the substrate with a thickness of 800 people under the following conditions and by adjusting the time. Conditions are ethylene (C2H4>gas;
'l 5CC) I hydrogen gas (t12): 25SCCH1
High frequency (13, 56 M1ll) output 50W, substrate temperature 150°C, gas pressure 0.9 Torr.

At this time, in order to analyze the protective layer, a silicon wafer (P type, electrical resistance: 10 to 20 Ω) was used in addition to the above substrate.
-cm, thickness: 525 μm) The film was also deposited on the pillars. As a result of structural analysis of these, the Raman spectra show that
It has a strong band peak at 1550 Cm-1 to 1600 cm', and also E, L.

In the measurement of S, it was found that the carbon bond state was a single bond Sp3 hybrid orbital because no peak was shown at 5 to 7 eV. Furthermore, the infrared absorption spectrum showed a strong peak at 2000 cm-1, 2500 CIl+', indicating that it was a C--C bond. For these reasons, this protective film is very durable.
It was found that it was an α-CiH) film.

'15f1 of an amorphous silicon photoreceptor with 1 soot and 3-layer grooves (charging ability, 2000 corona application cycles)
Table 1 shows the atomic ratio of the holons FB) to the 3i atoms in the barrier layer.

As shown in Table 1, the photoreceptor of the present invention has high charging ability and high durability against corona application. However, if the amount of boron added is small, the level of improvement in corona durability will be slightly low, and if the amount added is large, the charging ability will be significantly reduced.
~8.0X10-'.

Comparative Example 1 In Comparative Example 1, impurity gas (40 ppm B21-1 e
5000 barrier layers of amorphous silicon film without addition of 1nl-12> were deposited. Other conditions were the same as in the examples. Next, a photosensitive layer was prepared in the same manner as in the example.
Table 1 shows the characteristics of this photoreceptor, which was laminated with a protective layer in sequence.

At this time as well, the structure of the protective film was analyzed in the same manner as in the example, and it was confirmed that it was a diamond-like carbon film.

Characteristics of this photoreceptor (charging ability, corona application repetition 200
Table 1 shows the retention rate at 0 times. If boron (B) is not included in the barrier layer, the retention rate after repeated corona application 2000 times will drop significantly.

Table 1 Examples 10 to 13 Table 2 shows the experimental results in which the deposition conditions of the boron (B)-doped amorphous silicon barrier layer and the photosensitive layer were kept constant and the deposition conditions of the protective layer (impurity tope ratio) were changed. It is.

Examples 10 to 13 are slide glass/AI vapor deposited film (approximately 0
．． 6 μm) substrate with a plus V C of a planographic bipolar electrode arrangement.
After placing it in V D HH and evacuation to 1 x 10-6 Torr or less, Ar gas was flowed and bombarded with Ar ions (Ar gas: 5,03CCH1 Substrate temperature: 1
5-20°C, gas pressure: Q, Q5Torr, high frequency (1
3, 56H1IZ) De-kani 50W, processing time: 10 minutes) was performed. Next, a barrier layer of an amorphous silicon film doped with boron (B) was formed under the following conditions. 1Q
vo1%3i H41nH2 gas; 17°Q SCCH
1401) pm B2 H61nH2 gas: 8SCCH
1 High frequency output crab 60W, gas pressure: Q, 9 Torr, substrate temperature: 200°C, film thickness was 5000 by adjusting time.

The atomic ratio of boron (B) to silicon atoms was determined to be 3.8×10′ using 5IIIS in the same manner as in Examples 1 to 9. Next, an amorphous silicon photosensitive layer was placed on the above sample in the same manner as in Examples 1 to 9 for 15 minutes.
The layers were laminated to a thickness of 0 μm.

Next, a diamond-like carbon film containing boron (8) or phosphorus (P) was deposited on the above sample II as a substrate.
The film thickness of 0 people was laminated. A in Table 2 shows the impurity gas (B2
The amount of addition of Ha>, the atomic ratio of boron (B) to carbon, and the charging ability are shown. B indicates each value when doped with phosphorus (P). The film forming conditions were all the same as the IF5 film forming conditions of Examples 1 to 9 except for the impurity doping amount shown in Table 2. Regarding these photoreceptors, charging ability, f
The retention of the corona application wire after 2000 repetitions was investigated, and all had favorable results as shown in Table 2.

Table 2

Claims (5)

[Claims] (1) In an amorphous silicon electrophotographic photoreceptor in which a barrier layer made of amorphous silicon, a photosensitive layer made of amorphous silicon, and a protective layer made of a diamond-like carbon film are sequentially laminated on a conductive substrate,
An electrophotographic photoreceptor characterized in that the barrier layer contains an impurity atom consisting of an element of Group III of the periodic table. (2) Claim No. (2) characterized in that the impurity atom consisting of an element of Group III of the periodic table is boron (B).
The electrophotographic photoreceptor described in item 1). (3) Boron (B) in the barrier layer has an atomic ratio of 5 x 10^-^5 to 2.0 x 10^-^ to silicon atoms.
Claim No. 3 (1)
) The electrophotographic photoreceptor described in item 2. (4) Claim (1) characterized in that the diamond-like carbon film serving as the protective layer contains elements of Group III and/or Group V of the periodic table as impurity atoms.
) The electrophotographic photoreceptor described in item 2. (5) The electrophotographic photoreceptor according to claim (4), wherein the impurity atoms in the diamond-like carbon film are boron (B) and/or (P).