JP2000164347A - Display device and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an EL display device integrated with many fine picture elements (dots) at a low cost. SOLUTION: This display device is laminated with EL elements 12-15 on a silicon substrate 11, a nearly transparent membrane 16 is exposed on the back face side of the silicon substrate 11, and the luminescent light from the EL elements 12-15 is emitted from the back face side of the silicon substrate 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device and a method of manufacturing the same, and more particularly to a display device in which a part of an opaque substrate is made transparent and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, display devices using EL elements include:
For example, Synthetic Metals 91 (19
77) 3-7 "Organic multi-colo"
electroluminescence diss
In general, an anode, each layer as an EL layer, and a cathode are sequentially formed on a glass substrate, as in “play with finepixels” (Reference 1). A job that makes it easy to inject holes into the anode. A good conductor having a function, for example, ITO (indium tin oxide) is selected, and a cathode is made of, for example, an Al alloy having a work function for easily injecting electrons.

In addition to a glass substrate, a substrate on which an EL layer is formed is, for example, SiD98 DiGEST pp9.
49 "100-MHz Active-Matrix
Electroluminescent Displa
It is also known to use an SOI substrate formed using a substrate transfer technique, such as ys "(Reference 2).

In recent years, in order to reduce the dot pitch of the EL layer, for example, Literature 1 has realized a cathode interval of 30 μm in space using a photoresist lift-off method, and Literature 2 discloses a technique for fine processing of Si semiconductor. By utilizing this, a dot (pixel) pitch of 12 μm is realized.

[0005] Further, in a case where a member mainly made of silicon of a display portion of an opaque silicon substrate is removed by anisotropic etching to make it transparent, for example, Japanese Patent Application Laid-Open No. 5-2133 is disclosed.
8 and JP-A-6-67205.

[0006]

However, the prior art has four major problems as described below.

(1) First, in a display device using an organic EL, it is difficult to form an ITO electrode as an anode on the EL.

In order to obtain a fine dot pitch as described above, the best method is to use a known semiconductor processing technique. However, as shown in FIG. Since it is necessary to emit light above the substrate as long as it is used, the anode 2 necessarily formed above
05 becomes a transparent ITO electrode.

[0009] However, as described above, IT
The formation of an O electrode is difficult in terms of heat resistance because a temperature of about 200 ° C. is required for forming an ITO electrode.

(2) Secondly, in a heat-resistant inorganic EL in which an ITO electrode can be easily formed, the driving voltage is generally high (> 100 V). In the above-mentioned Document 2, this problem is solved by using an SOI substrate having good element isolation.

In general, when the voltage used increases, the size of the element and the size of the area required for element isolation become large, so that it is impossible to realize a fine pixel or dot pitch. The effective channel length of the CMOS which is the driving element in Document 2 is also 1.2 μm, which is several times larger than the currently processable dimensions.

[0012] Large elements or pixels make it difficult to reduce the size of the display device. A large substrate size and a large chip size cause a reduction in yield and a decrease in yield due to an increase in defects.

The direct-view display device requires at least 600 dpi (dot per inch), that is, a dot pitch of about 42 μm. HM with magnifying optics
In a display device such as a D (head mount display) or a projector, the smaller the size of the substrate on which the EL is mounted, the more likely it is that the device can be manufactured at lower cost.

From the above, at present, an organic EL that can be driven at a low voltage is more desirable than an inorganic EL.

(3) Third, as shown in FIG. 12, the first problem can be solved by using the transparent substrate 211, but the transparent substrate has some disadvantages as compared with the single crystal Si substrate. Is to have.

First, when the transparent substrate 211 is a glass substrate, the semiconductor film formed on the substrate is amorphous,
Alternatively, it is a polysilicon film, so that the carrier mobility in the film is lower than in single crystal silicon. In addition, other electrical characteristics such as leakage current tend to deteriorate, so that elements and circuits formed on the substrate have poor performance. However, in the current display device, the increase in the number of pixels is progressing at a rapid pace, and accordingly, the value of the pixel transistor having no driving ability and the peripheral driving circuit is greatly reduced.

When the transparent substrate 211 is an SOI substrate, the semiconductor film formed on the substrate is a single-crystal silicon film. Therefore, the elements and circuits formed on the substrate are single-crystal Si substrates. Performance equal to or better than
The price of the I substrate is much higher than that of the single crystal Si substrate.

The production of an SOI substrate formed by the above-described substrate transfer requires two substrates, a special substrate on which an original electric circuit is formed and a transparent substrate to be bonded, which is anti-ecological. . In addition, an SOS substrate, which is a typical SOI substrate, is several times as expensive as a normal single-crystal Si substrate, and is difficult to obtain.

(4) Fourth, as shown in FIG. 13, in an LCD in which a substrate is made transparent by silicon anisotropic etching, a transparent insulating thin film (membrane 235 to 238) remaining by anisotropic etching is removed. As is well known, the uniform gap of the LCD cannot be maintained without an appropriate tensile stress or the presence of a reinforcing material, which results in an increase in yield or manufacturing cost.

In order to guarantee a uniform gap by tensile stress, the membrane needs a large tensile stress close to the breaking strength of the membrane. When the stress increases, a phenomenon occurs in which the film is broken in the liquid during the anisotropic etching, and the yield is reduced.

In the case where a reinforcing material is provided, a large change in the temperature characteristics of the gap of the LCD may occur due to the difference in the coefficient of thermal expansion between the liquid crystal and the material used for the reinforcing material and the liquid crystal cell.
There is variation. This significantly degrades the performance of the LCD, making it virtually unusable.

[0022]

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned disadvantages and to provide an inexpensive EL display device in which a large number of fine pixels (dots) are integrated.

That is, the present invention relates to a display device in which an EL element is laminated on a silicon substrate, wherein a substantially transparent membrane is exposed at least in a display portion on a back surface side of the silicon substrate. The display device is characterized in that light emitted from the substrate is emitted from the back side of the silicon substrate.

Further, the present invention provides a step of forming a substantially transparent membrane in or on a silicon substrate, forming an anode of an EL element on the silicon substrate, and forming a light emitting layer of the EL element on the anode. Forming a cathode on the light emitting layer, and exposing the membrane by anisotropic etching from the back surface side of the silicon substrate of the display unit on which the EL element is formed. A method for manufacturing a display device characterized by the following.

The substrate on which fine pixels are integrated is a single-crystal Si substrate, and a large number of pixels and peripheral circuits having high driving capability are realized by the inexpensive single-crystal Si substrate. In the pixel display portion of the single-crystal Si substrate, a membrane mainly composed of at least a transparent film is formed by an additional process which does not cause a cost increase. An ITO electrode which is a transparent anode is formed on the membrane, and an EL layer and a cathode are formed thereon.
According to the present invention, since the EL layer is formed in a later step above the ITO electrode, the above-mentioned problem of heat resistance does not occur.

A substrate on which a pixel portion including an ITO electrode and a cathode and a known peripheral circuit for driving the pixel are mounted;
Alternatively, the silicon chip is formed mainly of Si on the rear surface side by an anisotropic Si etching method using a known alkaline aqueous solution or the like in a later step until the substantially transparent membrane is exposed from the rear surface of the substrate. The base member is removed by etching. Thereby, at least the pixel display portion is made transparent, and light emission from the EL layer can be guided to the outside,
The function as a display device is obtained.

Since the display device of the present invention is not an LCD, it is not necessary to realize a uniform liquid crystal cell gap. No tensile stress is required to achieve the aforementioned uniform cell gap, and the stress of the membrane can be set freely. Thus, there is a great deal of freedom in the members used for the membrane. For example, various CVD films having a compressive stress, which are common in semiconductor process materials, can also be employed. Also, there is no occurrence of film cracking in the etching step as described above.

Since the membrane of the present invention is fixed to, for example, an opposing wiring extraction substrate and is anisotropically etched, film cracking is greatly reduced. It is not necessary to consider the gap non-uniformity due to the difference in the coefficient of thermal expansion. In the present invention, some internal stress is generated due to the difference in the coefficient of thermal expansion between the membrane and the member to be fixed, but the stress is not large enough to cause cracking or peeling.

[0029]

(First Embodiment) FIG. 1 is a schematic sectional view of a simple matrix type display device according to a first embodiment of the present invention.

11 is a CZP (100) having a thickness of 625 μm
A silicon substrate 16 has a thickness of 1 formed thereon.
A μm LOCOS oxide film. A peripheral circuit 19 composed of an N-type MOSFET for driving pixels is formed in a peripheral portion of the silicon substrate 11.

Reference numeral 17 denotes an interlayer insulating film made of CVD SiO _{2 having a} thickness of 1 μm, on which a bonding pad 20 for electrical connection to the outside is formed. Reference numeral 18 denotes a 1 μm thick passivation film made of plasma SiN.

On top of this is an I for emitting light from the EL element.
An anode 15 composed of a TO electrode has a width of 10 μm
A total of 1000 lines are formed at an interval of 10 μm. Anode 15
Is connected to the peripheral circuit 19 by a wiring (not shown) by a method described later. After manufacturing from the silicon substrate 11 to the anode 15 by a known semiconductor process, the dining is performed to form a silicon chip 21 having a size of 25 mm square.

Thereafter, an aromatic tertiary amine, which is a hole transport layer 14 having a thickness of 500.degree., Is laminated on the display portion 25 of the silicon chip 21 by a vacuum evaporation method. Then 500mm thick
The organic metal complex which is the electron transport layer 13 is laminated by the same method. Finally, a total of 1000 Al alloy electrodes having a thickness of 1500 °, which are the cathodes 12, are formed at predetermined positions at a width of 10 μm, at intervals of 10 μm, and at an angle perpendicular to the anode 15.

An extraction substrate 22 on which an extraction electrode 23 having a similar wiring pattern is formed is bonded on the cathode 12 to the silicon chip 21 with a precision of ± 1 μm using a sealing material 24. The sealing material 24 also functions as a sealing material, preventing dirt and moisture from entering from the outside.

A 10 μm square area where the anode 15 and the cathode 12 intersect corresponds to a single EL element. That is,
The anode 15, the hole transport layer 14 as the EL layer, the electron transport layer 13, and the cathode 12 form a simple matrix of the EL element.

After the draw-out substrate 22 is connected, the EL display device is housed in an appropriate etching jig, and the silicon substrate 11 on the back side of the display section 25 is removed by a known anisotropic etching method. Will be

The etching is performed, for example, with a 22% aqueous solution of TMAH (tetramethylammonium hydroxide). Etching jig or silicon substrate 11
By performing selective etching using an etching mask or the like formed on the back surface of the device, only the display section 25 is made transparent. Etching is LOCO consisting mainly of thermal oxide film
When the S oxide film 16 is exposed, it stops automatically. As a result, the configuration of the silicon chip 21 of the display unit 25 is only a substantially transparent LOCOS film 16, an interlayer insulating film 17, a passivation film 18, and an approximately 15 μm membrane of the anode 15.

The EL element has a positive voltage applied to the anode 15 and a negative voltage applied to the cathode 1.
Light emission is performed by applying a negative voltage to 2. Light emission passes through the substantially transparent membrane and is guided out of the EL display device.

FIG. 2 shows an equivalent circuit diagram of the present embodiment.

The number of pixels (dots) is 1000 as described above.
× 1000, and one million EL elements 101 are composed of a vertical line 102 composed of an anode 15 and a horizontal line 1 composed of a cathode 12.
03 to form a simple matrix.

The matrix is driven by a vertical shift register (VSR) 104 as a peripheral circuit 19 and a horizontal shift register (HSR) as an external circuit (not shown in FIG. 1) connected to a horizontal line 103 drawn from the cathode 12 by an extraction electrode 23. ) 105. Both registers 10
Reference numerals 4 and 105 denote a signal processing circuit 10 which is also an external circuit.
A drive signal and a power supply voltage generated based on the video signal 107 are supplied from 6. Signal processing circuit 1 for VSR 104
06 and the power supply are made via the bonding pads 20.

According to the present embodiment, since the area where the electrodes 12 and 15 intersect is the unit size (thickness) of the electrode wiring, very fine pixels can be formed.

The EL element used in the present invention is not particularly limited, and any of an organic EL element and an inorganic EL element can be used. At least an anode layer and a cathode layer and one or more layers sandwiched between them An EL element composed of the organic compound layer of (1) is preferably used.

It is desirable that the material of the anode 15 has a large work function. For example, ITO, tin oxide, gold, platinum, palladium, selenium, iridium, copper iodide and the like can be used. On the other hand, it is desirable that the material of the cathode 12 has a small work function, for example, Mg / Ag, Mg, A
1, In, or an alloy thereof can be used.

The organic compound layer may have a single-layer structure or a multi-layer structure. For example, as shown in FIG.
And an electron transport layer 13 into which electrons are injected from the cathode layer 12. One of the hole transport layer 14 and the electron transport layer 13 is a light emitting layer. Further, a phosphor layer containing a phosphor may be provided between the hole transport layer and the electron transport layer. Further, it is also possible to adopt a configuration in which a hole transporting layer, an electron transporting layer, and a fluorescent layer are also used in a mixed single layer configuration.

As the hole transport layer 14, for example, N,
N′-bis (3-methylphenyl) -N, N′-diphenyl- (1,1′-biphenyl) -4,4′-diamine (TPD) can be used. Can be used.

[0047]

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[0048]

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[0049]

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[0050]

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[0051]

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Further, inorganic materials such as a-Si and a-SiC may be used.

For the electron transport layer 13, for example, tris (8-quinolinol) aluminum (hereinafter, Alq ₃ ) can be used, and the following materials can also be used.

[0054]

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[0055]

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[0056]

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[0057]

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Further, the electron transporting layer 13 or the hole transporting layer 14 can be doped with a dopant as shown below.

[0059]

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Preferably, a dielectric layer is provided between the anode layer 102 and the substrate. The dielectric layer can increase (lower) the reflection transmittance at a specific wavelength by laminating layers having different refractive indexes such as SiO ₂ and SiO. Alternatively, it is also possible to simply use a half mirror.

(Second Embodiment) FIG. 2 is a sectional view of a display section of an active matrix type display device according to a second embodiment of the present invention.

Reference numeral 16 denotes a LOCOS oxide film having a thickness of 1 μm, and 32 denotes a pixel electrode 15 serving as an anode formed thereon.
This is a TFT for driving the TFT. The TFT 32 is a P-type MOSFET in which a channel region having a channel length of 1 μm and a channel width of 5 μm is made of polysilicon. Pixel electrode 15
The TFT 32 and the TFT 32 are XY-addressed as described later, and form an active matrix array of 640 horizontal rows and 480 vertical rows.

The Al wiring 40 is connected to the drain of the TFT 32.
Are in contact with each other, and the wiring 40 has a thickness of 1500 mm,
It is connected to a pixel electrode 15 made of ITO having a size of 10 μm square.

On the pixel electrode 15, a hole transport layer 14 having a thickness of 500 °, an electron transport layer 13 also having a thickness of 500 °, and a thickness 15
An Al common electrode 12, which is a cathode of 00 °, is formed. The common electrode 12 is formed over the entire H640 × V480 pixel array.

FIG. 4 shows an equivalent circuit diagram of a pixel portion of the present embodiment.

The EL element 111 is formed between the pixel electrode 15 and the common electrode 12. The EL element 111 is addressed by a horizontal signal line 113 and a vertical scanning line 112.

Access transistor 1 composed of TFT
The vertical scanning line 112 is connected to the gate of the pixel 14, and the horizontal signal line 113 is connected to the drain. Horizontal signal line 113
When a driving signal generated from the video signal is applied to the pixel and the pixel is accessed by the vertical scanning line 112, the access transistor 114 is turned on, and the video information on the horizontal signal line 113 is transferred to the pixel driving transistor which is the TFT 32. It outputs to the gate of 115 and one terminal of the storage capacitor 116. The other terminal of the storage capacitor 116 has a constant voltage VC
Connected to OM.

The video information voltage applied to the gate is maintained even when the access transistor 114 is turned off. The pixel driving transistor 115 has a source 117 connected to the positive power supply voltage + V and a drain connected to the pixel electrode 15 which is one terminal of the EL element 111, and supplies a current corresponding to the video information voltage to the EL element 111. I do. Here, the common electrode 12 is connected to the GND potential 118.

According to this embodiment, it is possible to display a high quality image having a higher S / N than that of the first embodiment of the simple matrix. In addition, since the storage capacitor 116 is provided,
Even if the access time is short, the EL element 111 can emit light for a long time, and the duty ratio is improved.

Further, according to the present embodiment, since most of the shift registers and signal processing circuits for driving pixels can be integrated on a silicon chip, the system of the EL display device can be extremely simplified. Therefore, the display device can be provided at a lower cost.

The active matrix circuit used in the present invention is not limited to this. For example, each pixel is provided with a non-linear two-terminal element such as a diode or an MIM element and a storage capacitor, and a signal is written to the storage capacitor when a pixel is selected. , When not selected, E depends on the written signal.
A configuration in which the L element keeps emitting light may be used.

The material constituting the TFT 32 may be amorphous Si. The conductivity type may be N-type,
The type of device may be JFET, BJT, or the like.

(Third Embodiment) FIG. 5 is a schematic sectional view of a display device according to a third embodiment of the present invention. The configuration of the silicon chip 21 is the same as that of the first embodiment.

Reference numeral 21 denotes a silicon chip having an EL layer formed on the surface, and a protective glass 33 with a color filter (hereinafter referred to as CF) 34 is bonded to the back surface of the silicon chip 21 with an alignment accuracy of ± 1 μm.

The CF 34 on the protective glass 33 is of a known pigment dispersion type, and is a normal type used for a liquid crystal display device or the like. The CF 34 is connected to the pixels on the membrane formed on the display portion of the silicon chip 21 by ± 1 as described above.
The alignment is performed with an accuracy of μm. The alignment method includes the back surface of the silicon chip 21 and the protective glass 33.
A method of making alignment marks on the surface of the device and aligning it with a known aligner, and that white light emitted from the display unit is CF3
There is a method of performing alignment by detecting the colored light that has passed through the light source 4.

Although the former is simple, since the pixels are formed on the front side of the silicon chip 21, the alignment marks on the back side of the silicon chip 21 are ± 1 μm in advance with the pixels.
The alignment must be performed with the following accuracy. In the latter case, although the detection and alignment devices are complicated and expensive,
This is useful because a reliable matching effect can be obtained.

(Fourth Embodiment) FIG. 6 is a sectional view of a protective glass with a color filter used in a display device according to a fourth embodiment of the present invention.

The color filter 34 on the protective glass 33
A phosphor layer 36 is formed. The phosphor layer 36 produces white light from blue light having a short wavelength by a known function.

A similar system can be realized by applying the protective glass 33 not to the EL display device that emits white light as shown in the third embodiment but to the device that emits blue light.

According to the present embodiment, the number of EL materials that can be used for the EL element further increases.

(Fifth Embodiment) As a fifth embodiment of the present invention, an example in which a blue-white conversion phosphor layer is formed directly on a membrane can be considered.

Unlike the CF, the phosphor layer may be formed on the entire surface, and does not require precise alignment. Known coating methods, vapor deposition methods, and printing methods can be used for forming the phosphor layer.

(Sixth Embodiment) FIG. 7 is a schematic sectional view of a display device according to a sixth embodiment of the present invention. The configuration of the silicon chip 21 is the same as that of the first embodiment.

As described above, the silicon chip 2 of the display unit 25
Anisotropic etching is performed to make 1 transparent, but thereafter, the silicon chip 21 is only a membrane having a thickness of several μm. Therefore, the relationship between the membrane and the drawing substrate 22 for supporting and reinforcing the membrane is important.

In the present embodiment, the common electrode 12 is conductively bonded to the lead-out substrate 22 by a silver paste which is a conductive adhesive 86 that is unlikely to generate a bubble. 10 for bonding
This is because, when a large hour of μm or more is generated, the membrane may be damaged due to thermal and mechanical stress applied during anisotropic etching.

(Seventh Embodiment) FIG. 8 is a schematic sectional view of a display device according to a seventh embodiment of the present invention. The configuration of the silicon chip 21 is the same as that of the first embodiment.

Reference numeral 38 denotes a conductive liquid made of mercury, which realizes ohmic contact between the common electrode 12 and the extraction electrode 23 on the extraction substrate 22. Reference numeral 39 denotes an overcoat layer made of a polyimide resin having a thickness of 1 μm, and includes a common electrode 12, an electron transport layer 13 serving as an EL layer, and a hole transport layer 1.
4 to prevent an unintended electrical short between the EL layers. As in the sixth embodiment, mercury serving as the conductive liquid 38 has a function of alleviating various stresses generated during anisotropic etching.

In place of mercury which is a liquid metal,
It is also possible to use various organic and inorganic liquids containing a highly viscous organic substance such as polyethylene glycol, a conductive liquid crystal substance, and a conductive substance. However, these conductivity needs to satisfy a predetermined ohmic contact resistance.

The material of the overcoat layer 39 may be any other known material, such as, for example, Hymar resin.

(Eighth Embodiment) FIG. 9 is a schematic sectional view of a display device according to an eighth embodiment of the present invention.

Reference numeral 11 denotes a CZP (100) having a thickness of 625 μm.
SiMOX (separ) manufactured using a silicon substrate
ation by implanted oxygen
n) A buried oxide film 40 having a thickness of 1500 ° and a P-type epitaxial layer 41 having a thickness of 0.3 μm are formed on the front side of the substrate.

A driving transistor 42 composed of an N-type MOSFET for driving a pixel is provided in the epitaxial layer 41.
And an N-type MOSFET constituting the peripheral circuit 19 are formed by the same manufacturing process.

According to the present embodiment, a high-speed, high-performance single-crystal Si transistor can be used as a pixel driving transistor, so that a display device with more pixels and higher gradation can be realized. The process of manufacturing the transistor is different from that of the TFT of the second embodiment in that the peripheral circuit 1
The process is inexpensive because it is the same as the MOSFET constituting the semiconductor device 9. Also, the SiMOX substrate is not as high as the SOS substrate due to the realization of an inexpensive oxygen implanter. Therefore E
The silicon chip 21 for L lighting can be provided at a lower cost.

The opaque SOI substrate used in the present invention is not limited to the SiMOX substrate, but may be any inexpensive and ecological substrate.

(Ninth Embodiment) FIG. 10 shows a ninth embodiment of the present invention.
1 is a schematic sectional view of a display device according to an embodiment. The configuration of the silicon chip 21 is the same as that of the first embodiment.

Reference numeral 21 denotes one active matrix EL pixel.
It is a 25 mm square silicon chip formed of 000 × 1000 pieces. 15 is the thickness of the ITO electrode 15
The pixel electrode is an anode having a size of 00 ° and a size of 10 μm square. A cathode 12 is made of an Al alloy having a thickness of 1500 °. The cathode 12 has a thickness of 1 mm on the extraction substrate 22.
It is ohmically connected to a 500 ° Al lead electrode 23. The bonding of the lead-out substrate 22 and the chip 21 is performed by using the sealing material 24. At the same time as the application of the sealing material 24, the silver paste 43 is coated on the upper and lower conduction pads 44 formed on the silicon chip 21 and bonded. Thus, conduction between the silicon chip 21 and the drawing substrate 22 is ensured.

In this embodiment, since an external circuit connected to the draw-out substrate 22 is not required, the system of the EL display device is further simplified.

(Tenth Embodiment) A tenth embodiment of the present invention will be described.
As an embodiment, by providing a large number of contacts of the silver paste 43, the present invention may be applied to a simple matrix type EL display device.

[0099]

As described above, according to the present invention,
An inexpensive EL display device having a large number of fine pixels can be obtained. Further, by combining the present EL display device with a magnifying optical system, it is possible to obtain a high-definition, large-screen product such as an HMD and a projector.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing a first embodiment of a display device of the present invention.

FIG. 2 is an equivalent circuit diagram of the first embodiment.

FIG. 3 is a sectional view of a display unit of a display device according to a second embodiment of the present invention.

FIG. 4 is an equivalent circuit diagram of a pixel portion according to a second embodiment.

FIG. 5 is a schematic sectional view showing a third embodiment of the display device of the present invention.

FIG. 6 is a sectional view of a protective glass with a color filter used in a fourth embodiment of the display device of the present invention.

FIG. 7 is a schematic sectional view showing a sixth embodiment of the display device of the present invention.

FIG. 8 is a schematic sectional view showing a seventh embodiment of the display device of the present invention.

FIG. 9 is a schematic sectional view showing an eighth embodiment of the display device of the present invention.

FIG. 10 is a schematic sectional view showing a ninth embodiment of the display device of the present invention.

FIG. 11 is a view showing a conventional EL element.

FIG. 12 is a view showing a conventional EL element.

FIG. 13 is a schematic sectional view showing a conventional LCD.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Silicon substrate 12 Cathode (common electrode) 13 Electron transport layer 14 Hole transport layer 15 Anode (pixel electrode) 16 LOCOS film 17 Interlayer insulating film 18 Passivation film 19 Peripheral circuit 20 Bonding pad 21 Silicon chip 22 Leading substrate 23 Leading electrode 24 Sealing Material 25 Display 31 Wiring 32 TFT 33 Protective Glass 34 Color Filter 35 Adhesive 36 Phosphor Layer 37 Conductive Adhesive 38 Conductive Liquid 39 Overcoat Layer 40 Embedded Oxide Film 41 Epitaxial Layer 42 Driving Transistor 43 Silver Paste 44 pad for vertical conduction 101 EL element 102 vertical line 103 horizontal line 104 vertical shift register 105 horizontal shift register 106 signal processing circuit 107 video signal 111 EL element 112 vertical scanning line 113 horizontal signal line 14 Access transistor 115 Pixel driving transistor 116 Storage capacity 117 Source side 118 GND potential 201 Single crystal Si substrate 211 Transparent substrate 202, 212 Cathode 203, 213 Electron transport layer 204, 214 Hole transport layer 205, 215 Anode 231 Silicon substrate 233 Liquid crystal 235 Pixel electrode 236 LOCOS film 237 Interlayer insulating film 238 Passivation film 239 Peripheral circuit 240 Bonding pad 241 Silicon chip 242 Leading substrate 243 Leading electrode 244 Sealant 245 Display part

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H05B 33/12 H05B 33/12 E 33/14 33/14 A F term (Reference) 3K007 AB06 AB18 BA06 CA03 CB01 CC05 DA01 DB03 FA01 FA02 5C094 AA05 AA21 AA42 AA43 AA44 AA48 BA03 BA16 BA29 BA32 CA19 CA23 DA09 DA13 DB02 DB04 EA04 EB05 EB10 ED01 ED02 ED20 FA01 FA02 FB02 FB03 FB12 FB14 FB15 GB10

Claims (17)

[Claims] 1. A display device in which an EL element is laminated on a silicon substrate, wherein a substantially transparent membrane is exposed at least in a display portion on a back side of the silicon substrate, and light emitted from the EL element is provided. Is emitted from the back side of the silicon substrate. 2. The display device according to claim 1, wherein the EL elements are arranged in a two-dimensional matrix. 3. The display device according to claim 2, wherein the matrix forms an active matrix. 4. The active matrix includes a horizontal signal line and a vertical scanning line, both of which are connected to an access transistor, and the other main electrode of the transistor is connected to a storage capacitor and another different driving electrode. 4. The display device according to claim 3, wherein the display device is connected to a control electrode of a transistor, and drives the EL element by the driving transistor. 5. The display device according to claim 1, further comprising a color filter on a rear surface side of the silicon substrate of the display unit. 6. The display device according to claim 5, further comprising a phosphor layer between the silicon substrate and the color filter. 7. A wiring drawing substrate which is electrically connected to a cathode of an EL element.
The display device according to claim 1. 8. The display device according to claim 7, wherein the electrical connection is made by a conductive adhesive material that does not include a large hour. 9. The display device according to claim 7, wherein the electrical connection is made with a conductive liquid or a liquid crystal. 10. The display device according to claim 7, further comprising a contact for making an electrical connection between the wiring drawing substrate and the silicon substrate. 11. The display device according to claim 1, wherein the silicon substrate is an SOI (silicon-on-insulator) substrate having a substantially transparent insulating film in the substrate. 12. The display device according to claim 11, wherein a single crystal transistor for driving the EL element is formed in a display portion on an SOI substrate. 13. An EL element comprising: an anode on a silicon substrate;
13. The display device according to claim 1, wherein an EL layer and a cathode are stacked in this order. 14. The display device according to claim 13, wherein the EL layer is one or more organic compound layers. 15. A step of forming a substantially transparent membrane in or on a silicon substrate, forming an anode of an EL element on the silicon substrate, and forming a light emitting layer of the EL element on the anode. Forming at least a step of forming a cathode on the light-emitting layer and a step of exposing the membrane by anisotropic etching from the back surface side of the silicon substrate of the display unit on which the EL element is formed. A method for manufacturing a display device. 16. The method for manufacturing a display device according to claim 15, wherein alignment of a color filter arranged on the back surface side of the substrate of the display unit is performed using light emitted from the EL element. 17. After forming the cathode, the cathode is electrically connected to the wiring leading substrate, and when the wiring leading substrate and the silicon substrate are attached to each other, a contact for electrically connecting the two substrates is provided. 16. The device according to claim 15, wherein the components are formed simultaneously.
19. A method for manufacturing a display device according to item 16.