JPH01206674A - Photoelectric conversion device - Google Patents

Abstract

PURPOSE:To obtain a photoelectric conversion element small in size and excellent in reliability by a method wherein a light emitting element and a photodetector are formed into one piece in such a manner that either of them is directly formed on the other in lamination and an electrode of either of them is electrically isolated from that of the other. CONSTITUTION:A light emitting element 2 is formed directly on a photodetector 3 in lamination to be in one piece. The light emitting element 2 is composed of a luminous layer 21 such as an electrolytically luminous layer or the like and electrodes 22 and 23 provided to the upside and the underside of the luminous layer 21, the photodetector is composed of a photodetective layer 31 such as a solar cell which generates a photoelectric motive force and electrodes 22 and 23 provided to the upside and the underside of the photodetective layer 31. As mentioned above, the light emitting element 2 is very proximate to the photodetector 3, so that an optical signal transmitted from the element 2 is efficiently received by the detector 3 and the transmission of the optical signal is assuredly made, the electrodes of both the elements 2 and 3 are electrically isolated from each other, and an electrical interference between the elements 2 and 3 is hard to occur. By these processes, a photoelectric conversion device small in size and excellent in reliability can be obtained.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a photoelectric conversion device.

[Conventional technology]

In recent years, photoelectric conversion devices that include a light-emitting element and a light-receiving element and in which light from the light-emitting element is incident on the light-receiving element have been widely used in various fields. Such a photoelectric conversion device is combined with a semiconductor switching element such as an MO3 type semiconductor element, for example, and applies an electrical signal to a light emitting element, which is then converted into an optical signal and converted back into an electrical signal by a light receiving element, which is then sent to the semiconductor switching element. It is used to turn on and off.

On the other hand, as electronic devices become more compact, the reality is that there is a strong demand for miniaturization of so-called composite elements that combine elements with different functions.

[Problem to be solved by the invention]

Very small light-emitting elements and light-receiving elements are also manufactured. However, photoelectric conversion devices that combine pixel elements are not so small. Conventional devices combine individually manufactured light-emitting elements and light-receiving elements, which inevitably limits miniaturization.

On the other hand, as photoelectric conversion devices become smaller, electrical interference between light-emitting and light-receiving elements tends to occur, which may lead to frequent malfunctions. If malfunctions occur, it will naturally be unreliable and therefore impractical.

In view of the above circumstances, it is an object of the present invention to provide a photoelectric conversion device that is small and highly reliable.

[Means to solve the problem]

In order to solve the above problems, in the photoelectric conversion device according to the present invention, the light emitting element and the light receiving element are integrated by directly laminating one on the other, and the electrode of one element is connected to the other element. Electrically separated from the electrode.

[For production]

Since the light emitting element and the light receiving element are formed directly on the other and integrated, they are extremely small.

Moreover, since the light-emitting element is located very close to the light-receiving element, sufficient light can be effectively received, so optical signals can be exchanged efficiently between the light-emitting and light-receiving elements, ensuring optical signal transmission and increasing reliability. improves. The electrodes of each pixel element are electrically separated from the electrodes of the other element, making it difficult for electrical interference to occur between the pixel elements. Even if the device is miniaturized, it does not make it more likely to malfunction electrically.

[Embodiment] Hereinafter, one embodiment of a photoelectric conversion device according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows an embodiment of the photoelectric conversion device according to the present invention, FIG. The schematic perspective view, Figure (C), is a plan view of the electrode location.

The photoelectric conversion device 1 includes a light emitting element 2 and a light receiving element 3, and light emitted from the light emitting element 2 is received by the light receiving element 3. The light receiving element 3 is laminated directly on the light emitting element 2, and the pixel element 2.3 is integrated therein.

The light emitting element 2 is composed of a light emitting layer 21 such as an electroluminescent (EL full light emitting layer) and electrodes 22 and 23 provided above and below the light emitting layer 21, and the light receiving element 3 generates a photovoltaic force. It is composed of a light-receiving layer 31 such as a solar cell, and electrodes 32 and 33 provided above and below the light-receiving layer 31.

The basic operation of this photoelectric conversion device 1 is as follows.

When an electrical signal is applied between the electrodes 22, 23, the light emitting layer 2
An optical signal is generated at 1, and the optical signal enters the light receiving layer 31. A voltage is induced in the light-receiving layer 31 where the optical signal is incident, and the electrode 32
．． The electrical signal appears again during 33.

The light-emitting layer 21 is formed of a material that emits light of a wavelength that provides good light-receiving efficiency in the lower light-receiving layer N32. The light-receiving layer 31 is made of a silicon semiconductor layer with a Pin structure. Electrode 22.3
2 is made of a material with good transparency, such as ITO (indium tin oxide) or 5N02, and the light emitting layer 21
light is allowed to pass through the electrodes 22.32.

The electrode 23.33 does not need to be transparent, and is made of, for example, aluminum.
It is also possible to increase the light receiving efficiency by making the light reflected by Jii 31 also enter the light receiving Jii 31. Note that since it is difficult to fabricate a single-crystal semiconductor on an amorphous or non-amorphous material such as the electrode, in the structure of this embodiment, the above-mentioned EL layer is suitable as the light-emitting layer 31.

In the photoelectric conversion device 1, the electrode 22 of the light emitting element 2 and the electrode 32 of the light receiving element 3 are provided on the same surface, as shown in FIG. They are separated and not in contact.Therefore, the electrodes 22.23 of the light emitting element 2 and the electrodes 32.33 of the light receiving element 3 are in a state of being electrically separated from each other.This photoelectric conversion device 1
When operating, the light emitting element 2 applies a voltage from the electrode 22.23, and the light receiving element 3 extracts a signal from the electrode 32.33. Then, the circuit for light emitting element 2 and the light receiving element 3
Since the respective circuits are independently separated, no electrical interference occurs between the pixel elements 2 and 3. Therefore, there is no need to worry about electrical malfunctions. In addition, two electrodes 2
2.32 on the same plane has the advantage that two electrodes can be made at the same time in one electrode forming process.

FIG. 2 shows another embodiment of the photoelectric conversion device according to the present invention. A perspective view schematically showing a broken view (C1 is a plan view of an electrode location).

This photoelectric conversion device 11 also includes a light emitting element 12 and a light receiving element 13, and light emitted from the light emitting element 12 is received by the light receiving element 13. The light receiving element 13 is laminated directly on the light emitting element 12, and the pixel element 12.1
3 is integrated. The photoelectric conversion device 11 includes a light receiving element 1
This embodiment differs from the photoelectric conversion device 1 of the previous embodiment in the configuration of No. 3. The light receiving element 13 has a horizontal pin structure, whereas the previous light receiving element 3 has a vertical pin structure.

When an electrical signal is applied between the electrodes 22 , 23 , an optical signal exits from the light-emitting layer 21 and enters the light-receiving layer 31 .

A voltage is induced in the light-receiving layer 31 that receives the optical signal, and the electrode 32
．． An electric signal appears again between 33' and 33'. When the light-receiving element 13 has a horizontal structure, it is easy to manufacture even in the case of a three-dimensional structure in which the light-receiving element and a semiconductor switching element (FET, bipolar transistor, etc.) serving as a load are arranged on one semiconductor substrate.

In this photoelectric conversion device 11, as shown in FIG. 2(b), tc+, the electrode 22 of the light emitting element 2, the electrode of the light receiving element 3,
32.33 are provided on the same plane, but each electrode 22.33 is provided on the same plane.
32 and 33 are separated from each other and not in contact. Therefore, the electrodes 22, 23 of the light emitting element 2 and the electrodes 32, 33 of the light receiving element 3 are electrically separated from each other. When the three electrodes 22, 32, 33 are on the same surface, there is an advantage that the three electrodes can be formed simultaneously in the -th electrode forming process.

By electrically insulating the side surfaces of the photoelectric conversion devices 1.11 of the above embodiments, it is possible to arrange a large number of devices in parallel. In both photoelectric conversion devices 1.11, two or more electrodes are provided on the same surface, but in this case,
It becomes thinner by the thickness of the electrode layer attached. In addition, the photoelectric conversion device 1.11 can be formed so as to be stacked one after another from the lower layer to the upper layer, so it is easy to manufacture.

This invention is not limited to the above embodiments. As shown in the photoelectric conversion device 1' in FIG. 3 and the photoelectric conversion device 1'' in FIG. 4, the light emitting element 2' may have a horizontal structure. Picture electrodes 22' and 23' provided on the surface of the light emitting layer 21' are on the same surface.The light receiving element N31' of the light receiving element 3' is made of, for example, a silicon solar cell layer.Of course, the light emitting element 2' electrode 22'
, 23' and the electrodes 32' and 33' of the light receiving element 3' are, of course, electrically separated.

In each of the photoelectric conversion devices shown in FIGS. 1 to 3, the gap A between the electrodes may be filled with an insulating material. When the gap A is filled with an insulating material, the unevenness caused by the electrode is smoothed out, and it becomes easier to form a layer (e.g., a light emitting layer) thereon.
Moreover, the insulation between the electrodes is improved. In the above description, the light-emitting element is formed on the light-receiving element, but a structure in which the light-receiving element is formed on the light-emitting element may also be used. The light emitting layer may be a four diode layer instead of a solar cell layer.

〔Effect of the invention〕

As described above, the photoelectric conversion device according to the present invention has the following advantages.

Since one of the light emitting element and the light receiving element is laminated and integrated with the other, the size is reduced.

The light-emitting element and the light-receiving element are very close to each other, and the efficiency of transmitting and receiving optical signals is high, and the optical signals are reliably transmitted, resulting in high reliability.

The electrodes of the pixel elements are electrically separated from the electrodes of the other element, preventing electrical interference between the pixel elements and preventing malfunctions, improving reliability.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of the photoelectric conversion device according to the present invention, FIG. Figure (C), which is a schematic perspective view, is a plan view of the electrode location. FIG. 2 shows an embodiment of the photoelectric conversion device according to the present invention, FIG. FIG. 3 and FIG. 4 respectively show other embodiments of the photoelectric conversion device according to the present invention. It is a sectional view. 1.11... Photoelectric conversion device 2.12... Light emitting element 3.13... Light receiving element 22.23.32.
33... Electrode agent Patent attorney Takehiko Matsumoto Figure 1 (b) Figure 3 Figure 4 Procedural amendment (Spontaneous 1, Indication of the case 1988 Patent Application No. 032342 2, Name of the invention Photoelectric conversion Device 3, relationship with the case of the person making the amendment Patent Applicant Address 1048 Kadoma, Kadoma City, Osaka Name (583) Representative of Matsushita Electric Works Co., Ltd. 6. Specification subject to amendment and drawings 7. Contents of amendment■ On page 4, lines 11-12 of the specification, the statement [Light-receiving element 3 is above light-emitting element 2] has been replaced with "Light-emitting element 2 is on light-receiving element 2". 3.'' ■ On page 7, lines 4 and 5 of the specification, the statement ``The light-receiving element 13 is above the light-emitting element 12'' should be corrected to ``The light-emitting element 12 is above the light-receiving element 1.
3 above,” he corrected. (2) The words "Light-emitting element 2" in two places on page 8, line 1 and line 4 of page 8 of the specification have been corrected to read "Light-emitting element 12." (2) The text "Light-receiving element 3" is corrected to "Light-receiving element 13" in two places on page 8, line 1 and line 5 of the same page of the specification. ■ Figure 2 (a) and lbl of the attached drawings have been corrected as shown in the attached sheet. Figure 2 (a) (b)

Claims (1)

[Claims] 1. In a photoelectric conversion device comprising a light emitting element and a light receiving element, the light from the light emitting element is incident on the light receiving element,
A photoelectric conversion characterized in that the light-emitting element and the light-receiving element are integrated by directly laminating one on the other, and the electrode of one element is electrically separated from the electrode of the other element. Device.