JP2008130712A - Three terminal crystal silicon element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a crystal silicon light emitting element capable of providing a wanted light emission wavelength at high efficiency, with the wavelength being variable. <P>SOLUTION: A p-type silicon substrate 10 made from single crystal is prepared and a plurality of nano Si posts 15 are formed on one surface of the p-type silicon substrate 10. The nano Si posts 15 form a homojunction together with the silicon substrate 10, representing cylindrical pillar projections. On the surface of the silicon substrate 10, a silicon oxide film 16 in the region except for the upper surface of the nano Si post 15, a third electrode 17 so provided as to cover at least a part of the side surface of the nano Si post 15, and an insulating film 18 covering the surface of the third electrode 17 are formed. Further, a transparent electrode 19 is provided which forms a Schottky barrier wall 30 by contacting at least the upper surface of the nano Si post 15. A metal electrode 20 is formed on the other surface of the silicon substrate 10. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a crystalline silicon device, and more particularly to a highly efficient and highly functional three-terminal type crystalline silicon device composed of nano-sized crystalline silicon.

  In recent years, as the current control element has been replaced with a solid semiconductor from a vacuum tube, the illumination element has also been rapidly replaced with a solid light emitting element such as a III-V compound semiconductor from a fluorescent tube. There is no doubt about the progress of solidification of light emitting elements. However, Ga-based compound semiconductors, which are currently mainstream, require low-defect epitaxial growth on expensive sapphire substrates, and it is necessary to form pn junctions and quantum well structures. Therefore, it is difficult to provide an inexpensive light-emitting element in that a complicated multilayer film structure including Al, P, In, N, or the like must be formed.

In response to such problems, attempts have been made to obtain an inexpensive light-emitting element using silicon (Si), which is the most abundant material on the earth. Since Si is an indirect transition type, has low luminous efficiency, and has a band gap in the near infrared region, it has been considered unsuitable as a visible light emitting material. However, for example, it has been reported that visible light emission can be obtained from porous Si formed by anodic oxidation, so that nano-sized crystalline Si (hereinafter abbreviated as nano-Si) is attracting attention as a promising candidate for a visible light-emitting device. (For example, refer nonpatent literature 1).
The light emission phenomenon caused by nano-Si is considered to be a quantum confinement effect (expansion of band gap) that occurs by reducing the Si crystal to nano-size. In order to realize a three-terminal crystal silicon element, it is indispensable to increase the light emission efficiency to a practical level, and improvement of crystallinity including the surface state is the biggest problem. Further, in order to bring out the desired emission color, wavelength control is necessary, and the crystal size of nano-Si must be controlled with high accuracy.

Porous Si using the anodic oxidation method as described above erodes the Si surface in a porous manner by a unique oxidation action. Therefore, although the quality of the crystal itself is relatively good, it has been pointed out that the surface area is very large and the emission characteristics are unstable. Furthermore, since the shape can hardly be controlled, there is a problem that the emission wavelength cannot be controlled.
As a means for solving these problems, several methods have been proposed so far. For example, there is a device for forming a granular Si crystal on a substrate by using an ion implantation method, a sputtering method, a CVD (Chemical Vapor Deposition) method, etc., and additionally embedding it in a stable material such as silicon oxide (SiO ₂ ). (For example, refer to Patent Documents 1, 2, and 3).

Applied Physics Letters (Appl. Phys. Lett.), 1990, 57, 1046 Japanese Patent Laid-Open No. 8-17577 Japanese Patent Laid-Open No. 2004-296781 JP-A-8-307011

However, since the conventional methods described above are all formed by implanting or depositing Si or Si compound, there is a problem in the uniformity of crystals, and the particle size control is not satisfactory. .
In addition, since the conventional method is a two-terminal light emitting element that emits light by spontaneously recombining charges injected into nano-Si from a pair of electrodes, it is difficult to extract light with controlled wavelength with high efficiency. Met.

  The present invention has been made to solve the technical problems as described above, and an object of the present invention is to provide a three-terminal crystal silicon light-emitting element that can extract desired visible light with high efficiency. There is.

  For this purpose, as a result of intensive studies, the present inventors have made the third electrode (control electrode) to control the flow of electric charges on its side surface by making the nano-Si shape into a substantially cylindrical shape in order to increase the luminous efficiency. It was found that the luminous efficiency can be significantly improved. Furthermore, it has been found that the emission wavelength can also be controlled by controlling the potential applied to the third electrode.

That is, the three-terminal crystal silicon element of the present invention is characterized by comprising a pair of electrodes for injecting charges into the crystal silicon and a third electrode for controlling the flow of charges.
The three-terminal crystal silicon element of the present invention includes a single crystal silicon substrate having a pair of surfaces, and a plurality of substantially cylindrical single crystals that are continuous with one main surface of the single crystal silicon substrate and are substantially vertical. Silicon, a metal electrode located on the other main surface side of the single crystal silicon substrate, a pair of electrodes together with the metal electrode, a transparent electrode sandwiching the substantially cylindrical single crystal silicon, and a substantially cylindrical single crystal silicon And surrounding third electrodes.

  Here, the three-terminal crystalline silicon element further includes a first insulating film and a second insulating film, the metal electrode is in ohmic contact with the single crystal silicon substrate, and the first insulating film is the first insulating film. 3 and the substantially cylindrical single crystal silicon are preferably insulated, and the second insulating film preferably insulates the third electrode from the transparent electrode.

With such a configuration, charges (electrons / holes) injected from the pair of electrodes into the nano-Si column are efficiently recombined with the emission center.
Specifically, the potential is injected by applying a potential having the same polarity as the charge injected from the electrode (for example, a negative potential in the case where electrons are injected from the transparent electrode) to the third electrode. Since surface recombination in which electric charges do not contribute to light emission on the side surfaces of the nano-Si pillars is reduced, the light emission efficiency can be significantly improved.

Further, the transparent electrode may form a Schottky junction by contacting the substantially cylindrical single crystal silicon.
In this case, carrier injection can be performed at a low voltage (injection efficiency is improved), which is excellent in that the power consumption of the light-emitting element can be reduced.

Furthermore, a third insulating film in which tunneling of carriers is generated may be further provided, and the transparent electrode may be bonded to the substantially cylindrical single crystal silicon through the third insulating film.
In this case, since nano-Si is protected by a stable insulating film, it is preferable in that the luminous efficiency can be further improved and stabilized.

Alternatively, the substantially cylindrical single crystal silicon has a pn junction having a p-type and n-type two-layer structure in the height direction, and the transparent electrode is a p-type or n-type positioned on the upper layer of the substantially cylindrical single-crystal silicon. An ohmic contact may be formed in contact with one of the molds.
In this case, recombination of carriers injected from the transparent electrode through one conductivity type occurs inside the nano-Si column, so surface recombination that does not contribute to light emission is reduced, further improving luminous efficiency and stability. Can be achieved. Furthermore, compared to the case of using an insulating film, carrier injection can be performed at a lower voltage (improved injection efficiency), which is excellent in that the power consumption of the light emitting element can be reduced.

  Note that the bottom surface of the substantially cylindrical single crystal silicon is preferably in contact with the single crystal silicon substrate to form a homojunction.

On the other hand, the three-terminal crystal silicon element of the present invention preferably includes means for controlling the potential applied to the third electrode.
In addition, it is preferable to provide means for frequency-controlling the potential applied to the third electrode.

  In this case, if a potential at which an inversion layer is formed with respect to the conductivity type of nano-Si (for example, a positive potential in the case where electrons are injected into a p-type semiconductor) is applied to the third electrode, the nano-Si column Since the electron path in the inside is narrowed, the quantum confinement effect is increased and the emission wavelength can be controlled to a short wavelength. That is, in the prior art, the wavelength is uniquely determined by the diameter of the nano-Si, but the present invention has a feature that the wavelength can be controlled even by the third electrode. This is a single crystalline silicon light emitting device that not only can emit various monochromatic light emission, but can also emit white light by controlling the frequency of the voltage applied to the third electrode. have.

  According to the present invention, it is possible to obtain a three-terminal crystal silicon light-emitting element or the like that can extract a desired emission wavelength with high efficiency and can change the wavelength.

  The best mode for carrying out the present invention (embodiment) will be described in detail below with reference to the accompanying drawings. However, the present invention is not limited to the following embodiment, and Various modifications can be made within the range.

FIG. 1 is a partial cross-sectional view of a three-terminal crystal silicon element according to the present embodiment.
FIG. 2 is a bird's eye view of the three-terminal crystal silicon element shown in FIG.

As shown in FIGS. 1 and 2, a three-terminal crystal silicon element as a crystal silicon element includes a p-type silicon substrate 10 made of a single crystal having a pair of surfaces, and one surface of the silicon substrate 10 ( A plurality of nano-Si pillars (substantially cylindrical single crystal silicon) 15 are formed on the (main surface) side so as to be continuous and substantially vertical.
The nano-Si pillars 15 are in direct contact with the silicon substrate 10 to form a homojunction and are in the form of cylindrical pillar protrusions that are substantially perpendicular to the main surface of the silicon substrate 10. Further, a third surface provided on the main surface of the silicon substrate 10 so as to cover the silicon oxide film (insulating film) 16 and at least a part of the side surface of the nano Si pillar 15 in a region other than the upper surface of the nano Si pillar 15. An electrode (for example, aluminum) 17 and an insulating film 18 covering the surface of the third electrode 17 are formed. Further, a transparent electrode (for example, ITO) 19 provided so as to form a Schottky barrier 30 at least in contact with the upper surface of the nano-Si pillar 15 is provided. A metal electrode (for example, aluminum) 20 is formed on the other main surface (other surface) side of the silicon substrate 10 so as to be in ohmic contact with the silicon substrate 10.
The three-terminal crystal silicon element configured as described above is a highly efficient light emission and wavelength tunable light emitting element by applying a voltage with the transparent electrode 19 as a cathode, the metal electrode 20 as an anode, and the third electrode 17 as a control electrode. Operate.

FIG. 3 is an explanatory diagram showing a band structure and a carrier flow for explaining the operation principle of the three-terminal crystal silicon element shown in FIG. 1 and FIG.
As shown in FIG. 3, electrons injected from the transparent electrode 19 into the nano Si pillar 15 and holes injected from the metal electrode 20 through the silicon substrate 10 into the nano Si pillar 15 are included in the nano Si pillar 15. Light is emitted by being trapped in the recombination center. The reason why silicon having a near-infrared band gap emits visible light is due to a quantum confinement effect (expansion of the band gap) due to a reduction in crystal size (cylinder diameter). In other words, the three-terminal crystal silicon element having such a configuration can generate visible light relatively efficiently by controlling the diameter (Φsi) of the nano-Si pillar 15 even when there is no charge control by the third electrode 17. It can be taken out.

On the other hand, FIG. 4 is an explanatory view showing a band structure and a cross-sectional schematic diagram for explaining the principle of high efficiency and wavelength tuning of the three-terminal crystal silicon element shown in FIGS.
When no potential is applied to the third electrode 17, the thermal equilibrium state is as shown in FIG. 4A, and the band is bent downward at the interface of the silicon oxide film 16.
Here, when a negative potential is applied to the third electrode 17, the band bends upward at the interface of the silicon oxide film 16 as shown in FIG. 4B to form a storage layer. For this reason, electrons injected from the transparent electrode 19 into the nano-Si column 15 are easier to recombine near the center of the nano-Si column 15 than at the interface of the silicon oxide film 16 because of the energy level. As a result, recombination (does not contribute to light emission) in the vicinity of the silicon oxide film 16 where many defects and surface states exist is reduced, and the efficiency can be significantly improved.
On the other hand, when a positive potential is applied to the third electrode 17, as shown in FIG. 4C, the band bends greatly downward at the interface of the silicon oxide film 16, and an inversion layer is formed. A depletion layer is formed on the outside (inside the nano-Si pillar 15). For this reason, the passage of electrons injected from the transparent electrode 19 into the nano-Si column 15 is narrowed, and the band gap is expanded.

FIG. 5 is an explanatory diagram showing the band structure and carrier flow when a positive potential is applied to the third electrode 17 in order to explain the wavelength variable principle of the three-terminal crystal silicon element shown in FIG. 1 and FIG. is there.
As can be seen from FIG. 5, recombination occurs at a larger interband transition, and light having a shorter wavelength can be extracted.
In other words, it can function as a wavelength tunable light emitting element depending on the voltage applied to the third electrode 17, and can be operated as a white light emitting element by changing the potential at a certain period (frequency control). In addition, as compared with the prior art in which the emission wavelength is uniquely determined by the physical size of nano-Si, there is also a feature that the tolerance of size variation of nano-Si in manufacturing a light-emitting element having a desired wavelength can be greatly improved.
Even when a positive potential is applied, the electrons injected from the transparent electrode 19 into the nano-Si column 15 are applied to the nano-Si column rather than the interface of the silicon oxide film 16 due to the energy level, as in the case of applying a negative potential. Since recombination is easy in the vicinity of the center of 15, recombination in the vicinity of the silicon oxide film 16 where many defects and surface states exist (does not contribute to light emission) is reduced, and the efficiency can be significantly improved.

FIG. 6 is a partial cross-sectional view showing a modification of the three-terminal crystal silicon element shown in FIG.
Here, in order to avoid duplication of description, a different part from the example shown in FIG. 1 is demonstrated. In the modification shown in FIG. 6, an insulating film barrier is formed between the nano-Si column 15 and the transparent electrode 19 by providing a thin silicon oxide film 40 on the top surface of the nano-Si column 15.
That is, in the example shown in FIG. 1, electron injection from the transparent electrode 19 to the nano-Si pillar 15 is performed by tunnel injection through a Schottky barrier. On the other hand, in the modification shown in FIG. 6, electron injection from the transparent electrode 19 to the nano-Si pillar 15 is performed by tunnel injection through an insulating film barrier. In this modification, since the upper surface of the nano Si pillar 15 is covered with the stable silicon oxide film 40, surface recombination that does not contribute to visible light emission of electrons injected from the transparent electrode 19 into the nano Si pillar 15 is reduced. , Luminous efficiency can be improved.

FIG. 7 is a partial cross-sectional view showing another modification of the three-terminal crystal silicon element shown in FIG.
Here, in order to avoid duplication of description, a different part from the example shown in FIG. 1 is demonstrated. In the modification shown in FIG. 7, the nano-Si pillar 15 has a pn junction 50 having a two-layer structure of a p-type conductivity type and an n-type conductivity type in the height direction. Is in direct contact with the transparent electrode 19 to form an ohmic contact.
More specifically, when a p-type conductive layer (p layer) is used for the silicon substrate 10, a pn junction 50 is provided by providing a high-concentration n-type conductive layer (n + layer) 21 in the upper layer portion of the nano Si pillar 15. Form. Of course, the positional relationship between the p-type and the n-type may be reversed.
Here, the height direction refers to a direction substantially perpendicular to the main surface of the silicon substrate 10 on which the nano-Si pillars 15 are formed.

FIG. 8 is an explanatory diagram showing the band structure and carrier flow when a positive potential is applied to the third electrode in order to explain the operating principle of another modification of the three-terminal crystal silicon element shown in FIG. .
In the present embodiment, electrons flowing from the transparent electrode 19 into the n + layer 21 are injected into the lower p layer through the pn junction 50.
For this reason, since recombination of carriers occurs at a position deeper than the nano-Si column 15, surface recombination that does not contribute to visible light emission in a region where the transparent electrode 19 and the nano-Si column 15 are in contact or low energy ( The light (having a long wavelength) is reduced, and the luminous efficiency can be further improved.

Next, a method for manufacturing a three-terminal crystal silicon element to which the present embodiment is applied will be described.
FIG. 9 is a partial cross-sectional view showing a method for manufacturing a three-terminal crystal silicon element according to the present embodiment, in which the manufacturing method is shown in the order of manufacturing steps.
Here, first, a p-type single crystal silicon substrate 10 having a pair of (100) surfaces is prepared, and a block copolymer (for example, polystyrene (PS) and the like) is spin-coated on one surface (main surface) side. A thin film polymer 11 made of a polymethylmethacrylate (PMMA) copolymer) is applied to a thickness of about 25 nm and then baked at 220 ° C. for 3 hours to form a spherical PMMA layer 11b in the thin film of the PS layer 11a. A phase separation structure is formed.
For example, when a copolymer polymer having PS and PMMA having molecular weights of about 90,000 and 20,000 is used, the pitch is about 40 nm and the spherical PMMA layer 11b has a diameter of about 20 nm. Phase separation structure. The pitch and the diameter of the sphere can be controlled to various sizes by adjusting the molecular weight of the block copolymer and the ratio thereof (FIG. 9 (a)).

  Next, pores 12 having a nano-sized and six-fold plane pattern can be formed on the surface of the thin film polymer 11 by the RIE method using oxygen gas using the etching rate difference between PS and PMMA. This is because the etching rate of the PMMA layer 11b is 3 to 5 times faster than that of the PS layer 11a in the oxygen plasma (FIG. 9B).

  Next, inorganic SOG (Spin on Glass) is applied by spin coating, and a predetermined baking is performed to form an inorganic film 13a made of an inorganic material. By appropriately selecting the viscosity of the SOG, the inorganic film 13a in which the pores 12 are filled and flattened can be formed (FIG. 9C).

  Next, the surface of the inorganic film 13a is lightly etched (etched back) using the RIE method to form the inorganic film 13b remaining only in the pores 12. Next, etching is performed using the RIE method, and the PS layer 11a in a region not covered with the inorganic film 13a is removed to form an opening 14a (FIG. 9D).

  Next, using the inorganic film 13b as a mask, the upper layer portion (for example, a depth of 100 nm) of the silicon substrate 10 is etched using the RIE method to form a cylindrical protrusion (nano Si pillar 15) and a groove 14b. (FIG. 9 (e)).

Thereafter, the inorganic film 13b is removed by wet treatment with, for example, a hydrofluoric acid aqueous solution, and then heat treatment is performed in an oxidizing atmosphere at 850 ° C., so that the silicon oxide film 16 is formed on the bottom of the groove 14b and the surface of the nano Si pillar 15. Is provided. At this time, the diameter of the nano Si pillar 15 was controlled to about 3.5 nm by setting the silicon oxide film 16 to a desired thickness.
Next, after sputtering a low resistivity metal film such as aluminum, the entire surface is etched back to form the third electrode 17 embedded in the groove 14b (FIG. 9F).

  Next, an inorganic SOG (Spin on Glass) is applied by spin coating, a predetermined baking is performed, and then the entire surface is etched back to form an insulating film 18 made of an inorganic material. The upper surface is exposed (FIG. 9G).

  Finally, a transparent electrode (ITO) 19 made of an indium oxide compound is formed on the main surface side where the nano-Si pillars 15 are provided, and a metal electrode 20 made of aluminum is formed on the other surface side (FIG. 9 (h) )), A three-terminal crystal silicon element as shown in FIG. 1 can be obtained.

The size of the nano-Si pillar 15 of the three-terminal crystal silicon element manufactured by the above process was about 3.5 nm in diameter and about 80 nm in height. Further, when the metal electrode 20 was supplied as an anode, the transparent electrode 19 was used as a cathode, and the third electrode 17 was supplied with a zero potential, red light having a peak wavelength of about 700 nm was confirmed.
In this three-terminal type crystal silicon element, the nano-Si pillar 15 is made from the silicon substrate 10 having extremely good crystallinity, and therefore can have crystallinity with almost no defects. For this reason, luminous efficiency can be improved as compared with the prior art.

  Furthermore, when a negative potential is applied to the third electrode 17, recombination that does not contribute to visible light emission in the vicinity of the interface between the nano-Si column 15 and the silicon oxide film 16 can be reduced, and more efficient red light emission is achieved. did it. Further, by applying a positive potential to the third electrode 17 and changing the size thereof, the emission color from red to blue can be freely changed and extracted, and the positive potential applied to the third electrode 17 can be changed. It was confirmed that it has an unprecedented new function that white light can be produced by periodically changing the size (frequency control).

The nano-Si pillars 15 are processed by using the pores 12 having the same diameter obtained by phase separation of the block copolymer as an etching mask prototype, and controlling the refinement of the diameter by a subsequent oxidation step. A three-terminal crystal silicon element having excellent size uniformity can be formed. For this reason, the controllability of the emission wavelength is remarkably superior to that of the prior art. According to the experiment, the size variation could be suppressed to 5% or less.
Further, the thick silicon oxide film 16 surrounding the nano-Si pillar 15 has an effect of electrically insulating and separating from the transparent electrode 19 and enhancing the mechanical strength of the nano-Si pillar 15. Therefore, a high-efficiency light-emitting element with excellent wavelength controllability can be provided at a high yield and at a low cost.

In addition, although the 3rd electrode 17 illustrated aluminum, if it is a low resistance material and it is a material which is easy to process, there will be no restriction | limiting in particular. Although the transparent electrode 19 illustrated ITO, there will be no restriction | limiting in particular if it maintains transparency with respect to visible light and has electroconductivity. Moreover, although the metal electrode 20 illustrated aluminum, if it is the material which is excellent in electrical conductivity and can make ohmic connection with the silicon substrate 10, there will be no restriction | limiting in particular.
Furthermore, although the above embodiment showed the example which uses a p-type conductivity type for the silicon substrate 10, an n-type conductivity type may be sufficient. In this case, the n + layer 21 becomes a p + layer, and the positive / negative relationship applied to the cathode, the anode, and the third electrode 17 is also reversed.

  As described above in detail, according to the present embodiment, by providing the third electrode (control electrode) 17 that controls the flow of electric charges on the side surface of the substantially cylindrical nano-Si column 15, the luminous efficiency is improved. A three-terminal type crystal silicon element with significantly excellent emission wavelength control can be realized. This makes it possible to provide a novel three-terminal crystal silicon element at a low cost that can efficiently and efficiently extract visible light from a single color to white with a single element.

1, 6, and 7 exemplify a light emitting element using nano-Si, it can be applied to a power generation element (photovoltaic element) with the same configuration. That is, when nano-Si is irradiated with light from the transparent electrode side, carriers (electron / hole pairs) are generated, and power can be extracted from the pair of electrodes. In particular, a power generating element that is highly sensitive to visible light to ultraviolet light can be realized.
In addition, the three-terminal crystal silicon element to which the present embodiment is applied can be formed easily and in an arbitrary shape simply by adding several manufacturing steps to normal IC manufacturing. Therefore, a single chip may be combined with a control circuit, an amplifier circuit, a memory circuit, a protection circuit, or the like.
That is, by making various circuits and a three-terminal crystal silicon element into an IC on the same substrate, various functions can be added, functions can be improved, or costs can be reduced. The application is not limited to light emitting elements and power generation elements, but includes lasers, radars, communications, memories, sensors, electron emitters and displays.

It is the figure which showed the partial cross section of the 3 terminal type | mold crystal silicon element which concerns on this Embodiment. FIG. 3 is a bird's eye view of the three-terminal crystal silicon element shown in FIG. 1. FIG. 3 is an explanatory diagram showing a band structure and a carrier flow for explaining an operation principle of the three-terminal crystal silicon element shown in FIGS. 1 and 2. FIG. 3 is an explanatory diagram showing a band structure and a schematic cross-sectional view for explaining the principles of high efficiency and wavelength tuning of the three-terminal crystal silicon element shown in FIGS. 1 and 2. FIG. 3 is an explanatory diagram showing a band structure and a carrier flow when a positive potential is applied to a third electrode in order to explain the wavelength variable principle of the three-terminal crystal silicon element shown in FIGS. 1 and 2. It is a fragmentary sectional view which shows the modification of the 3 terminal type crystal silicon element shown in FIG. It is a fragmentary sectional view which shows the other modification of the 3 terminal type | mold crystal silicon element shown in FIG. FIG. 8 is an explanatory diagram showing a band structure and a carrier flow when a positive potential is applied to a third electrode in order to explain the operating principle of another modification of the three-terminal crystal silicon element shown in FIG. 7. It is a fragmentary sectional view showing a manufacturing method of a three terminal type crystal silicon device concerning this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Silicon substrate, 11 ... Thin film polymer, 11a ... PS layer, 11b ... PMMA layer, 12 ... Fine pore, 13a, 13b ... Inorganic film, 14a ... Opening part, 14b ... Groove part, 15 ... Nano Si pillar, 16 ... Silicon 17 ... third electrode, 18 ... insulating film, 19 ... transparent electrode, 20 ... metal electrode, 21 ... n-type conductive layer (n + layer), 30 ... Schottky barrier, 40 ... silicon oxide film, 50 ... pn junction

Claims (9)

In a crystalline silicon device using crystalline silicon,
A pair of electrodes for injecting charges into the crystalline silicon;
A third electrode for controlling the flow of the charge;
A three-terminal crystal silicon element characterized by comprising: A single crystal silicon substrate having a pair of surfaces;
A plurality of substantially cylindrical single crystal silicons that are continuous with one main surface of the single crystal silicon substrate and are substantially perpendicular;
A metal electrode located on the other main surface side of the single crystal silicon substrate;
A transparent electrode that forms a pair of electrodes together with the metal electrode and sandwiches the substantially cylindrical single crystal silicon;
A third electrode surrounding the substantially cylindrical single crystal silicon;
A three-terminal crystal silicon element characterized by comprising: The three-terminal crystal silicon element according to claim 2,
A first insulating film and a second insulating film;
The metal electrode is in ohmic contact with the single crystal silicon substrate,
The first insulating film insulates the third electrode from the substantially cylindrical single crystal silicon, and the second insulating film insulates the third electrode from the transparent electrode. 3-terminal crystal silicon element. The three-terminal crystal silicon element according to claim 3,
3. The three-terminal crystal silicon element, wherein the transparent electrode is formed with a Schottky junction by being in contact with the substantially cylindrical single crystal silicon. The three-terminal crystal silicon element according to claim 3,
A third insulating film that causes carrier tunnel injection;
The three-terminal crystal silicon element, wherein the transparent electrode is joined to the substantially cylindrical single crystal silicon through the third insulating film. The three-terminal crystal silicon element according to claim 3,
The substantially cylindrical single crystal silicon has a pn junction composed of a p-type and n-type two-layer structure in the height direction,
The three-terminal type crystalline silicon device, wherein the transparent electrode is in ohmic contact with one of p-type and n-type located in an upper layer of the substantially cylindrical single crystal silicon.   4. The three-terminal crystal silicon device according to claim 3, wherein the bottom surface of the substantially cylindrical single crystal silicon is in contact with the single crystal silicon substrate to form a homojunction. .   3. The three-terminal crystal silicon element according to claim 1, further comprising means for controlling a potential applied to the third electrode.   4. The three-terminal crystal silicon element according to claim 3, further comprising means for frequency-controlling the potential applied to the third electrode.

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