JP4899118B2 - Method for producing non-single crystal semiconductor material - Google Patents

Description

  The present invention relates to a non-single-crystal semiconductor material, a photoelectric conversion element, a light-emitting element, and a method for producing a non-single-crystal semiconductor material having excellent characteristics by precisely distributing the particle size of a material containing silicon nanocrystals.

Conventionally, a material in which nanoparticles are dispersed in an amorphous matrix has excellent characteristics for reducing deterioration of hydrogenated amorphous silicon. Also, excellent properties such as working as a light emitting material are known. In recent years, a nanocrystal-embedded amorphous silicon material can be obtained in a boundary region between an amorphous silicon preparation condition and a microcrystalline silicon preparation condition (hydrogen dilution rate condition).
[D. Tsu, et. al. Applied Physics Letter 71, 1317 (1997)]

  However, in the above-described technique, the parameter region in which the boundary region material can be obtained is extremely narrow, and there is a problem that this material cannot be obtained even if it is slightly deviated from the predetermined condition. In addition, since a thin film silicon material grows with anisotropy in the film growth direction, there is a problem that uniform characteristics cannot be obtained in the whole film especially when the film is grown in such a boundary region. Furthermore, there is currently no method for precisely controlling the particle size and distribution of silicon nanocrystals. That is, a material containing silicon nanocrystals has not been realized at low cost, and a particularly precise particle size distribution is extremely difficult.

  In view of the above points, an object of the present invention is to realize a nanocrystal-embedded amorphous material in which nanocrystals are almost uniformly embedded in an amorphous silicon material, and have excellent characteristics in non-single-crystal semiconductor materials, photoelectric conversion elements, light emission It is to provide a device and a method for manufacturing a non-single-crystal semiconductor material.

According to claim 1 of the present invention, an amorphous material mainly composed of silicon, including a film forming step of forming a semiconductor layer on a base material by a CVD method using a silane-based or germane-based gas and a hydrogen-based gas. A non-single crystal semiconductor material in which crystalline silicon having a particle size of 1 nm to 5 nm is dispersed, or a non-single crystal semiconductor material in which crystalline germanium having a particle size of 1 nm to 5 nm is dispersed in an amorphous material mainly composed of germanium. The film formation step is performed under a high hydrogen dilution rate condition where the hydrogen dilution rate condition expressed by (flow rate of hydrogen gas) / (flow rate of silane or germane gas) is 25 to 100. It is possible to provide a method for producing a non-single-crystal semiconductor material, characterized by alternately repeating a step and a step of forming a film under a low hydrogen dilution rate condition where the hydrogen dilution rate condition is 2 to 20.

  Therefore, a nanocrystal-embedded amorphous material in which nanocrystals are embedded almost uniformly in an amorphous silicon material can be realized, and a method for manufacturing a non-single-crystal semiconductor material having excellent characteristics can be provided.

According to claim 2 of the present invention , silicon is mainly used, which includes a film forming step for forming a semiconductor layer on a base material by a CVD method using a silane-based or germane-based gas and a hydrogen-based gas. Production of non-single-crystal semiconductor material in which crystalline silicon having a particle size of 1 nm to 3 nm is dispersed in an amorphous material or non-single-crystal semiconductor material in which crystalline germanium having a particle size of 1 to 3 nm is dispersed in an amorphous material mainly composed of germanium In the method, the film forming step is performed under a high hydrogen dilution rate condition in which a hydrogen dilution rate condition represented by (flow rate of hydrogen gas) / (flow rate of silane or germane gas) is 25 to 70. It is possible to provide a method for producing a non-single crystal semiconductor material, characterized by alternately repeating a film forming step and a film forming step under a low hydrogen dilution rate condition where the hydrogen dilution rate condition is 2 to 10. That.

  Therefore, a nanocrystal-embedded amorphous material in which nanocrystals are embedded almost uniformly in an amorphous silicon material can be realized, and a method for manufacturing a non-single-crystal semiconductor material having excellent characteristics can be provided.

According to the first aspect of the present invention, a nanocrystal-embedded amorphous material in which nanocrystals are embedded almost uniformly in an amorphous silicon material (or amorphous germanium material) is realized, and a non-single-crystal semiconductor material having excellent characteristics is manufactured. A method can be provided.

According to the invention of claim 2 , a nanocrystal-embedded amorphous material in which nanocrystals are embedded almost uniformly in an amorphous silicon material (or amorphous germanium material) is realized, and a non-single-crystal semiconductor material having excellent characteristics is manufactured. A method can be provided.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

(First embodiment)
A first embodiment of the present invention will be described with reference to FIG.

Non-single-crystal semiconductor material according to the first embodiment of the present invention, as shown in FIG. 1, a silicon (or germanium) crystalline silicon particle size 1nm~5nm amorphous material 3 mainly made of (or crystalline germanium) 2 is a non-single-crystal semiconductor material 1 characterized by being scattered.

  A method for manufacturing the non-single crystal semiconductor material 1 will be described.

  The non-single-crystal semiconductor material 1 can be formed by any combination of plasma CVD, photo CVD, thermal CVD, and hot-wire CVD, but preferably A plasma CVD method is used. The frequency of the high frequency voltage applied in the plasma CVD method is 13 to 120 MHz, more preferably 13 MHz to 80 MHz.

  Examples of the gas used include, but are not limited to, monosilane, disilane, dichlorosilane, silicon tetrafluoride, germane and the like as silane or germanium gases. Examples of the dilution gas include hydrogen and deuterium. If necessary, methane, acetylene, or the like can be used to increase the band gap, or a rare gas such as helium, neon, argon, xenon, or krypton.

The non-single crystal semiconductor material manufacturing method (hydrogen dilution rate modulation method) to which the non-single crystal semiconductor material according to the first embodiment of the present invention is applied, as shown in FIG. A step of forming a high hydrogen dilution rate film (non-single crystal semiconductor material) 1 under a high hydrogen dilution rate condition of [ ( flow rate of hydrogen-based gas ) / (flow rate of silane-based or germane gas)], and hydrogen The step of forming the low hydrogen dilution rate film 4 under low hydrogen dilution rate conditions with low dilution rate conditions is repeated alternately.

  Either the high hydrogen dilution rate film 1 or the low hydrogen dilution rate film 4 may be formed first. FIG. 2 shows a structure in which the high hydrogen dilution rate film 1 and the low hydrogen dilution rate film 4 are alternately formed and stacked.

  The process of forming a film under a high hydrogen dilution rate condition and the process of forming a film under a low hydrogen dilution rate condition may be changed at regular intervals, and the flow rate may be changed in pulses, or may be changed gently. It doesn't matter.

Crystals are likely to grow under high hydrogen dilution conditions, resulting in the structure shown in FIG. 1, and crystal growth is difficult under low hydrogen dilution conditions. The crystal is grown under this high hydrogen dilution condition, and the film forming condition is set to the low hydrogen dilution condition before the particle diameter is not more than the proper range of the above-mentioned particle diameter. By repeating this, the particle diameter is in the range of 1 to 5 nm. A semiconductor material containing nanoparticles (crystalline silicon or crystalline germanium 2) can be made.

  Fig. 3 shows that when either the high hydrogen dilution rate condition or the low hydrogen dilution rate condition is modulated, either the silane or germane source gas flow rate or the dilution gas flow rate (in this case, the silane flow rate) is changed. The silane flow rate, the hydrogen flow rate, and the dilution rate are shown with respect to the film formation time. The dilution rate R1 is a low hydrogen dilution rate condition, and the dilution rate R2 is a high hydrogen dilution rate condition. Thus, when modulating the high hydrogen dilution rate condition and the low hydrogen dilution rate condition, one of the flow rate of the silane-based or germane-based source gas and the flow rate of the dilution gas may be changed.

  FIG. 4 shows the film formation time when both the flow rate of the silane or germane source gas and the flow rate of the dilution gas are changed simultaneously when the high hydrogen dilution rate condition and the low hydrogen dilution rate condition are modulated. Shows the silane flow rate, hydrogen flow rate, and dilution rate. The dilution rate R1 is a low hydrogen dilution rate condition, and the dilution rate R2 is a high hydrogen dilution rate condition. Thus, when modulating the high hydrogen dilution rate condition and the low hydrogen dilution rate condition, both the flow rate of the silane or germane source gas and the flow rate of the dilution gas may be changed simultaneously.

  When changing the gas flow rate, it is preferable to perform time modulation by automatically controlling the mass flow controller. FIG. 5 shows the silane flow rate, the hydrogen flow rate, and the dilution rate with respect to the film formation time when the input power is increased at the time of manufacturing the high hydrogen dilution rate film in synchronization with the time modulation and the introduced power is decreased at the time of manufacturing the low hydrogen dilution rate film. The input power value is shown. As described above, when changing the gas flow rate, it is also preferable to increase the input power when producing the high hydrogen dilution rate film in synchronism with time modulation and reduce the introduced power when producing the low hydrogen dilution rate film.

  Note that the modulation time is desirably at least longer than the gas residence time in the film formation chamber in both conditions. This is because if the gas flow time is shorter than the gas residence time, even if the gas flow rate is changed in the mass flow controller, the gas is not completely replaced in the reaction vessel, and a desired gas flow rate ratio may not be obtained.

  Moreover, it is preferable that the hydrogen dilution rate ratio at the time of high hydrogen dilution rate conditions is the range of 25-100. If it is larger than this range, the crystal size is often too large or good film quality cannot be obtained. If it is smaller than this range, crystallization hardly occurs. Moreover, it is preferable that the hydrogen dilution rate ratio at the time of low hydrogen dilution rate conditions exists in the range of 2-10. Within this range, good film characteristics can be maintained.

  Furthermore, it is preferable that the layer (high hydrogen dilution rate film 1) stacked in the step of forming a film under the high hydrogen dilution rate condition is in the range of 1 nm to 6 nm. If it is thinner than 1 nm, crystal growth does not occur, and if it is thicker than 6 nm, the crystal grains become too large and the film characteristics deteriorate. The layer stacked in the step of forming a film under the low hydrogen dilution rate condition is preferably in the range of 1 nm to 20 nm. If it is thinner than 1 nm, it is difficult to stop the growth of crystal grains in a layer grown under a high hydrogen dilution rate condition, and if it is thicker than 20 nm, the film characteristics deteriorate.

  Furthermore, when the sublayers are alternately stacked using the high hydrogen dilution rate condition and the low hydrogen dilution rate condition, the thickness of the sublayer stacked under the high hydrogen dilution rate condition is set to 1 nm to 4 nm, and the low hydrogen dilution rate condition is set. It is important that the thickness of the laminated sub-layer is 1 nm or more and 20 nm or less. If the thickness of the sublayer produced under the low hydrogen dilution rate is thinner than 1 nm, it is difficult to stop the growth of crystal grains in the layer grown under the high hydrogen dilution rate, and if it exceeds 20 nm, the photodegradation cannot be suppressed. If the thickness of the sublayer produced under the high hydrogen dilution ratio is 1 nm or less, crystal grains cannot grow, and if it is 4 nm or more, the crystal grain size becomes too large and the crystal grains become recombination centers.

  In addition, the layer (high hydrogen dilution rate film 1) laminated in the step of forming a film under the high hydrogen dilution rate condition, and the layer (low hydrogen dilution rate film 4) laminated in the step of forming a film under the low hydrogen dilution rate condition. Respectively correspond to the nanoparticle-containing layer and the amorphous layer described above, but in the layer laminated in the film forming step under the high hydrogen dilution rate condition, a thin amorphous layer (so-called so-called amorphous layer is formed before the crystal grains grow). Since the nucleation occurs after the incubation layer) is grown and the crystal growth proceeds, the nanocrystals that grow are generally smaller than the film thickness of the layer prepared under high hydrogen dilution rate conditions.

  As described above, the non-single-crystal semiconductor material that is the high hydrogen dilution rate film 1 has a laminated structure with the low hydrogen dilution rate film 4, so that it is stable to light irradiation and has excellent electro-optical characteristics. It can be a semiconductor material. Further, when the particle size is in the range of 1 nm to 5 nm, a quantum size effect can be obtained and excellent characteristics can be obtained.

The volume fraction of crystalline silicon or crystalline germanium 2 is preferably 0.5% or more and 10% or less with respect to the non-single-crystal semiconductor material 1. Within this range, good device characteristics can be obtained when used as various devices utilizing the characteristics of nanoparticles.

  As a base material used in the first embodiment of the present invention, various materials can be used depending on applications. Either an insulating material or a conductive material may be used, and either flexible or non-flexible is possible. Specifically, for example, glass, quartz, polymethyl methacrylate, polycarbonate, polystyrene, polyethylene sulfide, polyethersulfone, polyolefin, polyethylene terephthalate, polyethylene naphthalate, triacetyl cellulose, polyvinyl fluoride film, ethylene-tetrafluoroethylene copolymer Resin, weather resistant polyethylene terephthalate, weather resistant polypropylene, glass fiber reinforced acrylic resin film, glass fiber reinforced polycarbonate, polyimide, transparent polyimide, fluorine resin, cyclic polyolefin resin, polyacryl resin, SUS thin plate, Al foil, etc. It can be used, but is not limited to these. These may be used as a single substrate, but a composite substrate in which two or more kinds are laminated can also be used.

(Second Embodiment)
The semiconductor material to which the non-single-crystal semiconductor material according to the present invention is applied can be applied to various fields.

  For example, as a second embodiment of the present invention, by providing electrodes on the top and bottom of the semiconductor material, a light-emitting element with high luminous efficiency and a low manufacturing method can be obtained (see FIG. 6: described later).

  In the case of a light emitting element, it is preferable that various conditions such as particle size and film forming conditions are as follows.

  The particle size is preferably in the range of 1 nm to 5 nm, and if in this range, excellent emission characteristics are exhibited due to the quantum size effect.

  In addition, the volume fraction of the crystal part is preferably 0.5% or more and 10%, and if it is lower than 0.5%, the luminous efficiency is poor, and if it exceeds 10%, the grain size of the nanocrystal is controlled. Is extremely difficult.

  The thickness of the layer stacked in the step of forming a film under a high hydrogen dilution rate condition is preferably 1 nm or more and 6 nm or less. If it is thinner than 1 nm, it is difficult to grow crystal grains, and if it is thicker than 6 nm, the crystal grain size becomes too large, resulting in poor luminous efficiency.

  The thickness of the layer stacked in the step of forming a film under the low hydrogen dilution rate condition is preferably 1 nm or more and 20 nm or less. If it is thinner than 1 nm, it is difficult to stop the growth of crystal grains in the layer grown under the high hydrogen dilution rate condition, and if it is thicker than 20 nm, the number of nanocrystals contained in the film is reduced and the luminous efficiency is deteriorated.

  It is preferable that the hydrogen dilution rate ratio of the high hydrogen dilution rate condition is in the range of 25 to 100, and the hydrogen dilution rate ratio of the low hydrogen dilution rate condition is in the range of 2 to 10. If it exceeds 100, the low hydrogen dilution rate condition film underlying the high hydrogen dilution rate condition film may be crystallized, and the crystal size may exceed 5 nm and the quantum size effect may not be obtained. Good light emission characteristics can be maintained by controlling the hydrogen dilution rate ratio of the low hydrogen dilution rate condition in the range of 2 to 10.

  The electrodes used in the light emitting element are not limited to the light emitting side being transparent and the non-light emitting side being transparent or opaque. Examples of transparent electrodes include oxides such as tin oxide, indium oxide and zinc oxide having a thickness of 10 to 500 nm, or metal thin films such as gold, platinum, palladium, silver and alloys thereof having a thickness of 5 to 15 nm. However, it is not limited to these. These light-transmitting conductive films are preferably layers that transmit the emitted light well and have a low surface resistance, such as gold and platinum layers having a thickness of 5 to 15 nm, and tin-doped indium oxide layers having a thickness of 30 to 200 nm. preferable. The transparent electrode is deposited by, for example, a sputtering method, a vacuum evaporation method, an ion plating method, a plasma CVD method, a sol-gel method, a printing method, or the like. As the opaque electrode, for example, a metal thin film made of a metal such as iron, chromium, titanium, tantalum, niobium, molybdenum, nickel, aluminum, or cobalt, or an alloy such as nichrome or stainless steel is used, but is not limited thereto. These metal layers are provided by means of, for example, vacuum deposition, sputtering, ion plating, printing, or plating.

  In order to increase the weather resistance of the light-emitting element, a gas barrier layer can be provided on the light-emitting element. For example, any one of silicon oxide (SiOx), silicon nitride (SiNx), aluminum oxide (AlxOy) alone, or a mixed deposition layer of two or more kinds, or an inorganic-organic hybrid coat layer A composite layer in which one kind or a combination of two or more kinds can be suitably used. Vapor deposition layers such as silicon oxide (SiOx), silicon nitride (SiNx), and aluminum oxide (AlxOy) can be easily formed on a substrate by, for example, vapor deposition, sputtering, CVD, dipping, or sol-gel. Can be formed. The thickness of such a gas barrier layer is suitably in the range of 5 to 500 nm, particularly preferably in the range of 30 to 150 nm.

  Specifically, as shown in FIG. 6, a photoelectric conversion element having a pair of electrode layers 7 and 11, a p-type semiconductor 8, an i-type semiconductor 9, and an n-type semiconductor 10 is used. A single crystal semiconductor material 1 can be used. By doing in this way, the thin film silicon solar cell which is very stable with respect to light irradiation and has high conversion efficiency can be provided.

  When the photoelectric conversion element having the non-single-crystal semiconductor material 1 of the present invention is used, it is preferable that various conditions such as particle size and film forming conditions are as follows.

  The particle size is preferably in the range of 1 nm to 3 nm. Within this range, good solar cell characteristics can be realized while suppressing light degradation. When the particle size is 3 nm or less, the band gap of the crystalline silicon is increased by the quantum size effect and is about the same as that of amorphous silicon, so that the photoexcited carriers are not recombined at the crystalline portion.

  When a silicon-based semiconductor material in which crystal grains larger than 5 nm are normally embedded in an amorphous matrix is used for a power generation layer portion (i layer) of a thin-film silicon-based solar cell, the amorphous portion (a-Si: H is 1). .About.7 to 1.8 eV) and the crystal part (crystal Si is about 1.1 eV), the photoexcited carriers recombine in the crystal part, thereby deteriorating the characteristics of the solar cell. become.

  It is also important that the volume fraction of the crystal part is 0.5% or more and 3%. If it is less than 0.5%, the light deterioration cannot be suppressed, and if it exceeds 3%, it becomes difficult to maintain good device characteristics.

  Moreover, a solar cell characteristic will improve more that the hydrogen dilution rate ratio of high hydrogen dilution rate conditions is the range of 25-70, and the hydrogen dilution rate ratio of low hydrogen dilution rate conditions is the range of 2-10. Crystallization is unlikely to occur when the hydrogen dilution ratio of the high hydrogen dilution ratio is less than 25, and when it exceeds 70, the low hydrogen dilution condition underlying it is crystallized during the formation of the high hydrogen dilution condition film. The crystal size may become too large. By controlling the hydrogen dilution rate ratio of the low hydrogen dilution rate condition within the range of 2 to 10, good film characteristics can be maintained.

  The layer stacked in the step of forming a film under a high hydrogen dilution rate condition is preferably in the range of 1 nm to 4 nm. If it is thinner than 1 nm, the crystal grains contained in the film become too large, and if it is thicker than 4 nm, the crystal grain size becomes too large and the crystal grains become recombination centers. The layer stacked in the step of forming a film under the low hydrogen dilution rate condition is preferably in the range of 1 nm to 20 nm. If it is thinner than 1 nm, it is difficult to stop the growth of crystal grains in a layer grown under a high hydrogen dilution rate condition, and if it becomes thicker than 20 nm, photodegradation cannot be suppressed.

  Moreover, a well-known thing can be used as an electrode of a photoelectric conversion element.

  For example, a combination of a transparent electrode and a back electrode provided on the front side where sunlight enters can be used.

  Examples of transparent electrodes include oxides such as tin oxide, indium oxide and zinc oxide having a thickness of 10 to 500 nm, or metal thin films such as gold, platinum, palladium, silver and alloys thereof having a thickness of 5 to 15 nm. However, it is not limited to these. These light-transmitting conductive films are preferably layers that transmit incident sunlight well and have low surface resistance. For example, a gold-platinum layer having a thickness of 5 to 15 nm and a tin-doped indium oxide layer having a thickness of 30 to 200 nm are used. preferable. The transparent electrode is deposited by, for example, a sputtering method, a vacuum evaporation method, an ion plating method, a plasma CVD method, a sol-gel method, a printing method, or the like.

  A grid electrode made of metal or the like can be formed on the transparent electrode. In this case, the grid electrode can be produced by, for example, a screen printing method, a vacuum deposition method, a sputtering method, an ion plating method, a plasma CVD method, a sol-gel method, or the like.

  As the back electrode, for example, a metal thin film made of a metal such as iron, chromium, titanium, tantalum, niobium, molybdenum, nickel, aluminum, cobalt, or an alloy such as nichrome, stainless steel is used, but is not limited thereto. These metal layers are provided by means of, for example, vacuum deposition, sputtering, ion plating, printing, or plating. Further, for example, a transparent electrode having a thickness of 2 nm to 500 nm can be provided between the metal layer and the photoelectric conversion layer. Further, as the back electrode, for example, a so-called “see-through solar cell” can be used in which a transparent conductive oxide thin film is used to make the entire surface of the solar cell transparent.

  Moreover, in order to raise the weather resistance of a solar cell element, it is also possible to provide a gas barrier layer on either the above layer or between layers. For example, any one of silicon oxide (SiOx), silicon nitride (SiNx), aluminum oxide (AlxOy) alone, or a mixed deposition layer of two or more kinds, or an inorganic-organic hybrid coat layer A composite layer in which one kind or a combination of two or more kinds can be suitably used.

  Vapor deposition layers such as silicon oxide (SiOx), silicon nitride (SiNx), and aluminum oxide (AlxOy) described above can be easily formed on a substrate by, for example, vapor deposition, sputtering, CVD, dipping, sol-gel, or the like. Can be formed. The thickness of such a gas barrier layer is, for example, suitably in the range of 5 to 500 nm, particularly preferably in the range of 30 to 150 nm.

  Furthermore, in the non-single crystal solar cell mainly composed of silicon and germanium described above, either a pin type (super straight type) solar cell or a nip type (substrate type) solar cell may be used. A plurality of elements may be stacked like a triple solar cell.

  FIG. 6 is a cross-sectional view showing a pin-type thin film silicon solar cell in which an i-layer is produced by the hydrogen dilution rate modulation method of the present invention (Comparative Example 1).

  In Comparative Example 1, a transparent conductive film 7 is provided on a transparent substrate 6 with a thickness of, for example, 200 nm, and a p-type amorphous silicon thin film 8 is provided thereon with, for example, a plasma CVD method. Subsequently, an i-type amorphous silicon thin film 9 and an n-type amorphous silicon thin film 10 containing nanocrystal grains of the present invention are provided, and finally a transparent conductive film 11 and a metal electrode 12 are provided.

  FIG. 7 is a program diagram showing the processing steps for producing an i-type amorphous silicon thin film (sample 1) containing nanocrystal grains.

  The program modulates the dilution rate under the conditions of high hydrogen dilution rate (hydrogen dilution rate 40, equivalent to film thickness 3 nm) and low dilution rate condition (hydrogen dilution rate 4, equivalent to film thickness 12 nm). Produced. That is, each of the high hydrogen dilution rate film (corresponding to a film thickness of 3 nm) and the low hydrogen dilution rate (corresponding to a film thickness of 12 nm) is about 20 layers each.

  FIG. 8 is a program diagram showing another processing step when producing an i-type amorphous silicon thin film (sample 2) containing nanocrystal grains.

  The dilution rate was modulated under high hydrogen dilution rate conditions (hydrogen dilution rate 25, film thickness equivalent to 2 nm) and low dilution rate conditions (hydrogen dilution rate 5, film thickness equivalent to 2 nm), and an i-layer was produced with a total film thickness of 300 nm. . That is, the high hydrogen dilution rate film (equivalent to a film thickness of 2 nm) and the low hydrogen dilution rate (equivalent to a film thickness of 2 nm) are approximately 75 layers each.

  FIG. 9 is a program diagram showing another processing step when producing an i-type amorphous silicon thin film containing nanocrystal grains (Comparative Example 2).

  The dilution rate was modulated under high hydrogen dilution rate conditions (equivalent to hydrogen dilution rate of 40 and film thickness of 6 nm) and low dilution rate conditions (equivalent of hydrogen dilution rate of 4 and film thickness of 4 nm) to produce i layers with a total film thickness of 300 nm. . That is, the laminated film of the high hydrogen dilution rate film (equivalent to a film thickness of 6 nm) and the low hydrogen dilution rate (equivalent to a film thickness of 4 nm) each have about 30 layers.

  FIG. 10 is a diagram showing the solar cell characteristics before and after light irradiation (pseudo sunlight AM1.5 1SUN 500 hours irradiation) of the samples prepared in FIGS. 7 to 9 and the comparative example described above.

  Samples 1 and 2 prepared in the present embodiment are extremely stable with respect to light irradiation, whereas Comparative Example 1 shows a high value in the initial value before deterioration, and greatly converted after light irradiation. Efficiency is decreasing. In Comparative Example 2, the initial efficiency itself is low because the particle size of the nanocrystal is too large.

  From the above results, it can be seen that the solar cell according to the present embodiment exhibits the most excellent device characteristics after light irradiation.

(Third embodiment)
A semiconductor material to which the non-single-crystal semiconductor material according to the present invention is applied can also be used as a light-emitting element.

  FIG. 11 is a program diagram showing processing steps when producing a non-single crystal material (sample 3) containing nanocrystal grains of the present invention.

  The dilution rate is modulated under the high hydrogen dilution rate condition (hydrogen dilution rate 40, equivalent to film thickness 3 nm) and low dilution rate condition (hydrogen dilution rate 4, equivalent to film thickness 12 nm). A non-single crystal material was fabricated on a thickness of 1.1 mm. That is, each of the high hydrogen dilution rate film (corresponding to a film thickness of 3 nm) and the laminated film of the low hydrogen dilution rate (corresponding to a film thickness of 4 nm) is about 43 layers each.

  FIG. 12 is a program diagram showing processing steps when producing a non-single crystal material (sample 4) containing nanocrystal grains of the present invention.

  Quartz substrate (film) with a total film thickness of 300 nm by modulating the dilution ratio under high hydrogen dilution conditions (hydrogen dilution ratio 25, equivalent to film thickness 2 nm) and low dilution ratio conditions (hydrogen dilution ratio 5, equivalent to film thickness 2 nm) A non-single crystal material was fabricated on a thickness of 1.1 mm. That is, the high hydrogen dilution rate film (equivalent to a film thickness of 2 nm) and the low hydrogen dilution rate (equivalent to a film thickness of 2 nm) are approximately 75 layers each.

  FIG. 13 is a program diagram showing processing steps when producing a non-single crystal material (comparative example 3) containing nanocrystal grains of the present invention.

  Quartz substrate (film) with a total film thickness of 300 nm by modulating the dilution ratio under high hydrogen dilution conditions (hydrogen dilution ratio 40, film thickness equivalent to 18 nm) and low dilution conditions (hydrogen dilution ratio 4, film thickness equivalent to 2 nm) A non-single crystal material was fabricated on a thickness of 1.1 mm. That is, the high hydrogen dilution rate film (equivalent to a film thickness of 18 nm) and the laminated film having a low hydrogen dilution rate (equivalent to a film thickness of 2 nm) each have about 15 layers.

  FIG. 14 is a graph showing an evaluation of the light emission characteristics of the non-single-crystal material produced for the sample and the comparative example described above.

  A continuous wave He-Cd laser (wavelength: 325 nm) was used for excitation of light emission. The results are shown in FIG. In Samples 3 and 4, strong light emission is observed in the visible region, whereas in Comparative Example 3, no light emission is observed.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the configurations and conditions described in the mobile phones of the embodiments. Although light emission is observed as photoluminescence, light can be emitted by injecting carriers into a non-single-crystal material including nanocrystals. In addition, when such injection light emission is realized, it can be used as a light source when the input / output of the semiconductor integrated circuit device is performed by light, and since it is made of the same silicon process, it has good process consistency and is inexpensive and reliable. A highly light-emitting element can be provided.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

Sectional drawing which showed the non-single-crystal semiconductor material which concerns on 1st Embodiment of this invention. Sectional drawing which showed the manufacturing method of the non-single-crystal semiconductor material to which the non-single-crystal semiconductor material which concerns on 1st Embodiment of this invention is applied. When modulating the high hydrogen dilution rate condition and the low hydrogen dilution rate condition according to the first embodiment of the present invention, when either the flow rate of the silane or germane source gas or the flow rate of the dilution gas is changed The figure which showed the silane flow rate, hydrogen flow rate, and dilution rate with respect to the film-forming time. When the high hydrogen dilution rate condition and the low hydrogen dilution rate condition according to the first embodiment of the present invention are modulated, both the flow rate of the silane or germane source gas and the flow rate of the dilution gas are changed simultaneously. The figure which showed the silane flow rate, hydrogen flow rate, and dilution rate with respect to film-forming time. The silane flow rate relative to the film formation time when the input power is increased at the time of manufacturing the high hydrogen dilution rate film in synchronization with the time modulation according to the first embodiment of the present invention and the input power is decreased at the time of manufacturing the low hydrogen dilution rate film, The figure which showed the hydrogen flow rate, the dilution rate, and the input electric power value. Sectional drawing which showed the pin type thin film silicon solar cell which produced i layer by the hydrogen dilution rate modulation method. The program figure which showed the process process at the time of producing the i-type amorphous silicon thin film containing the nanocrystal grain which concerns on 2nd Embodiment of this invention. The program figure which showed another processing process at the time of producing the i-type amorphous silicon thin film containing the nanocrystal grain which concerns on 2nd Embodiment of this invention. The program figure which showed another processing process at the time of producing the i-type amorphous silicon thin film containing the nanocrystal grain which concerns on 2nd Embodiment of this invention. The figure which shows the result of having irradiated pseudo-sunlight to the sample produced in FIGS. 7-9, and a comparative example, and measuring. The program figure which showed the process process at the time of producing the non-single-crystal material containing the nanocrystal grain concerning 3rd Embodiment of this invention. The program figure which showed the process process at the time of producing the non-single-crystal material containing the nanocrystal grain concerning 3rd Embodiment of this invention. The program figure which showed the process process at the time of producing the non-single-crystal material containing the nanocrystal grain concerning 3rd Embodiment of this invention. The figure which shows the light emission characteristic in the room temperature of the non-single-crystal material produced by the hydrogen dilution rate modulation method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Non-single-crystal semiconductor material, 2 ... Crystal germanium, 3 ... Amorphous material, 3.4, Sample, 4 ... Low hydrogen dilution rate film, 6 ... Transparent substrate, 7 ... Transparent conductive film, 8 ... i-type semiconductor, 9 ... n-type semiconductor, 11 ... transparent conductive film, 12 ... metal electrode

Claims (2)

Crystalline silicon having a particle size of 1 nm to 5 nm in an amorphous material mainly composed of silicon, including a film forming step of forming a semiconductor layer on a substrate by a CVD method using a silane-based or germane-based gas and a hydrogen-based gas A method for producing a non-single crystal semiconductor material in which crystalline germanium having a particle size of 1 nm to 5 nm is dispersed in a non-single crystal semiconductor material or an amorphous material mainly composed of germanium ,
The film forming step is a step of forming a film under a high hydrogen dilution rate condition in which a hydrogen dilution rate condition represented by (flow rate of hydrogen gas) / (flow rate of silane or germane gas) is 25 to 100; A method for producing a non-single-crystal semiconductor material, characterized in that the steps of film formation under low hydrogen dilution rate conditions where the hydrogen dilution rate conditions are 2 to 20 are repeated alternately. Crystalline silicon having a particle size of 1 nm to 3 nm in an amorphous material mainly composed of silicon, including a film forming step of forming a semiconductor layer on a base material by a CVD method using a silane-based or germane-based gas and a hydrogen-based gas A method for producing a non-single crystal semiconductor material in which crystalline germanium having a particle size of 1 nm to 3 nm is dispersed in a non-single crystal semiconductor material or an amorphous material mainly composed of germanium ,
The film forming step is a step of forming a film under a high hydrogen dilution rate condition in which a hydrogen dilution rate condition represented by (flow rate of hydrogen gas) / (flow rate of silane or germane gas) is 25 to 70; A method for producing a non-single-crystal semiconductor material, wherein the steps of forming a film under a low hydrogen dilution rate condition where the hydrogen dilution rate condition is 2 to 10 are alternately repeated.

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