JP2014122950A - Electro-optic device and electronic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electro-optic device which has higher transmittance for light in a wavelength range where sensitivity is high in human visual sense characteristics and for light in a wavelength range where degradation by light is easily caused, and which is bright and reduces progression of degradation by light.SOLUTION: The electro-optic device comprises: an element substrate body 10a; and a storage capacitance 17 comprising a pixel electrode 15, a capacitive electrode 16 disposed between the element substrate body 10a and the pixel electrode 15 and opposing to the pixel electrode 15, and a dielectric layer 14. A spectral distribution of light transmitted through the element substrate body 10a and the storage capacitance 17 shows peaks in a wavelength range from 530 nm to 590 nm and in a wavelength range from 400 nm to 460 nm.

Description

  The present invention relates to an electro-optical device and an electronic apparatus including the electro-optical device.

  As the electro-optical device, for example, an active drive type liquid crystal device used as light modulation means (light valve) of a liquid crystal projector can be cited. A pixel of the liquid crystal device includes a pixel circuit including a pixel electrode, a transistor that controls switching of the pixel electrode, and a storage capacitor for holding an image signal written to the pixel electrode.

  In this type of liquid crystal device, brighter and higher contrast image display is preferable. In the display area where light is modulated, the number of elements that block light is reduced, and the capacitance value of the storage capacitor is increased, so that the image signal at the pixel electrode is increased. It was necessary to improve the potential holding characteristics.

  Therefore, a transparent conductive film provided in an upper layer of the transistor element, a translucent dielectric film formed on the transparent conductive film, and the transistor element in an opening region through which light can be transmitted in the display region There has been proposed an electro-optical device having a storage capacitor composed of a transparent pixel electrode electrically connected to (Patent Document 1). Since the electro-optical device has a storage capacitor made of a transparent film, the storage capacitor can be increased in capacity while suppressing a decrease in light utilization efficiency (transmittance).

JP 2010-176119 A

  However, if a transparent conductive film and a transparent pixel electrode are simply stacked with a translucent dielectric film in between, the light transmitted through the aperture region is absorbed by these thin films or reflected at the interface between these thin films. As a result, the desired transmittance may not always be obtained. In other words, when a transparent storage capacitor is provided in the opening region of the pixel, there is a problem that it is necessary to optimize the transmittance of light transmitted through the opening region.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  Application Example 1 An electro-optical device according to this application example includes a substrate, a pixel electrode, a capacitor electrode disposed opposite to the pixel electrode between the substrate and the pixel electrode, the pixel electrode, and the capacitor. A storage capacitor including a dielectric layer sandwiched between electrodes, and a spectral distribution of light transmitted through the substrate and the storage capacitor is a wavelength range of 530 nm to 590 nm and a wavelength range of 400 nm to 460 nm And has a peak.

The electro-optical device according to this application example includes a substrate and a storage capacitor including a pixel electrode, a capacitor electrode, and a dielectric layer, and a spectral distribution of light transmitted through the substrate and the storage capacitor has a wavelength of 530 to 590 nm. It has a peak in which the transmittance increases in the range and the wavelength range from 400 nm to 460 nm.
Light in the wavelength range of 530 nm to 590 nm is light in a wavelength range with high sensitivity in human visibility characteristics, and corresponds to light that most affects the brightness of display. Accordingly, it is possible to provide a brighter electro-optical device by having a high transmittance with respect to light in a wavelength range with high sensitivity to human visibility.
The light in the wavelength range of 400 nm to 460 nm is light on the short wavelength side in the visible light range, has higher light energy than the light on the long wavelength side in the visible light range, and deteriorates the electro-optical device (light degradation). ) Is easy to proceed. Having a high transmittance for the light on the short wavelength side means that the absorption and reflection of the light on the short wavelength side is small, and the influence of the absorption and reflection of the light on the short wavelength side is small. Become. That is, it is difficult to be affected by the light on the short wavelength side, and deterioration due to the light on the short wavelength side is less likely to proceed. Therefore, it is possible to provide a highly reliable electro-optical device that is less prone to light degradation and excellent in light resistance.

  Application Example 2 In the electro-optical device according to the application example described above, it is preferable that the dielectric layer includes a first dielectric film and a second dielectric film.

  When a defect (for example, a pinhole) occurs in the first dielectric film, the defect portion of the first dielectric film is compensated by the second dielectric film. In other words, by configuring the dielectric layer to include the first dielectric film and the second dielectric film, the defect density of the dielectric layer can be reduced, and the dielectric layer can be made thinner. Yes. By reducing the thickness of the dielectric layer, the dielectric layer has high transparency with respect to light in the visible light range, that is, light in the wavelength range of 530 nm to 590 nm and light in the wavelength range of 400 nm to 460 nm. On the other hand, it has a high transmittance.

  Application Example 3 In the electro-optical device according to the application example described above, it is preferable that the first dielectric film is hafnium oxide and the second dielectric film is aluminum oxide.

  Hafnium oxide, which is a constituent material of the first dielectric film, has a feature that the dielectric constant is large, and aluminum oxide, which is a constituent material of the second dielectric film, has a feature that the leakage current is small. Yes. When the dielectric layer has a stacked structure of hafnium oxide and aluminum oxide, a capacitor element (storage capacitor) having a large capacitance density, a low leakage current, and an excellent withstand voltage can be formed.

  Application Example 4 In the electro-optical device according to the application example, the pixel electrode and the capacitor electrode are ITO films, and the film thickness of the pixel electrode and the film thickness of the capacitor electrode are in the range of 126 nm to 154 nm. It is preferable.

Part of the light transmitted through the pixel electrode and the capacitor electrode is reflected (multiple reflection) at the interface between the pixel electrode and the capacitor electrode and another film (layer) in contact with the pixel electrode and the capacitor electrode. When light interference (multiple interference) occurs between the transmitted light and the transmitted light, the transmittance of the light transmitted through the pixel electrode and the capacitor electrode is the optical path length (film thickness × refractive index) or light of the pixel electrode and the capacitor electrode. It depends on the wavelength of For example, depending on the wavelength of light transmitted through the pixel electrode and the capacitor electrode, the light may be attenuated by the interference of the light, and the transmittance of the light transmitted through the pixel electrode and the capacitor electrode may be reduced.
When the pixel electrode film thickness and the capacitor electrode film thickness are in the range of 126 nm to 154 nm, the light due to the interference of the light with respect to the light in the wavelength range of 530 nm to 590 nm and the light in the wavelength range of 400 nm to 460 nm is transmitted. Attenuation is suppressed, and a decrease in the transmittance of light transmitted through the pixel electrode and the capacitor electrode is suppressed. Accordingly, when the film thickness of the pixel electrode and the film thickness of the capacitor electrode are in the range of 126 nm to 154 nm, the storage capacitor has a high transmittance in the wavelength range of 530 nm to 590 nm and in the wavelength range of 400 nm to 460 nm. become.

  Application Example 5 In the electro-optical device according to the application example described above, it is preferable that the pixel electrode has a film thickness in the range of 140 nm to 154 nm, and the capacitor electrode has a film thickness in the range of 126 nm to 140 nm.

A storage capacitor having a transparent electrode (pixel electrode, capacitor electrode) film thickness of 140 nm made of an ITO film has a light transmittance near a wavelength (555 nm) at which the human eye is most sensitive in a bright environment. Can have a larger peak and provide a brighter display.
When the film thickness of the transparent electrode is thinner than 140 nm, the peak wavelength (peak wavelength) at which the transmittance increases is shifted to a shorter wavelength side than 555 nm, and when the film thickness of the transparent electrode is thicker than 140 nm, the peak wavelength is from 555 nm. Shift to the longer wavelength side. When the film thickness of the pixel electrode is set in the range of 140 nm to 154 nm (thicker than 140 nm) and the film thickness of the capacitor electrode is set in the range of 126 nm to 140 nm (thinner than 140 nm), the film thickness of the pixel electrode is increased. The influence of having a thickness greater than 140 nm and the effect of making the thickness of the capacitor electrode thinner than 140 nm are offset, and the peak wavelength is substantially the same as when the thickness of the pixel electrode and the capacitance electrode is 140 nm. It becomes like this. That is, the storage capacity of this application example has a peak in which the transmittance increases in the vicinity of the wavelength (555 nm) at which the human eye has the highest sensitivity in a bright environment, so that a brighter display can be provided.

  Application Example 6 In the electro-optical device according to the application example described above, it is preferable that the pixel electrode has a film thickness in the range of 126 nm to 140 nm, and the capacitor electrode has a film thickness in the range of 140 nm to 154 nm.

A storage capacitor having a transparent electrode (pixel electrode, capacitor electrode) film thickness of 140 nm made of an ITO film has a light transmittance near a wavelength (555 nm) at which the human eye is most sensitive in a bright environment. Can have a larger peak and provide a brighter display.
When the film thickness of the transparent electrode is thinner than 140 nm, the wavelength (peak wavelength) of light that increases the transmittance shifts to a shorter wavelength side than 555 nm, and when the film thickness of the transparent electrode is larger than 140 nm, the peak wavelength is from 555 nm. Shift to the longer wavelength side. When the film thickness of the pixel electrode is set in the range of 126 nm to 140 nm (less than 140 nm) and the film thickness of the capacitor electrode is set in the range of 140 nm to 154 nm (when thicker than 140 nm), the film thickness of the pixel electrode is increased. The effect of making the thickness thinner than 140 nm and the effect of making the thickness of the capacitive electrode thicker than 140 nm are offset, and the pixel electrode and the capacitive electrode have substantially the same peak wavelength as when the thickness is 140 nm. It becomes like this. That is, the storage capacity of this application example has a peak in which the transmittance increases in the vicinity of the wavelength (555 nm) at which the human eye has the highest sensitivity in a bright environment, so that a brighter display can be provided.

  Application Example 7 In the electro-optical device according to the application example, the dielectric layer is a multilayer film in which the first dielectric film and the second dielectric film are alternately stacked, and the dielectric layer The thickness of the body layer is preferably in the range of 20 nm to 50 nm.

  The film thickness of the dielectric layer is in the range of 20 nm to 50 nm, and since the dielectric layer is a very thin thin film, it has high transparency to visible light. That is, the dielectric layer has a high transmittance with respect to light in the wavelength range of 530 nm to 590 nm and light in the wavelength range of 400 nm to 460 nm.

  Application Example 8 An electronic apparatus according to this application example includes the electro-optical device described in the application example.

  An electronic apparatus according to this application example includes the electro-optical device according to the application example described above, and has a wavelength range in which light having a high sensitivity in human visual sensitivity characteristics is used with high efficiency and light degradation is likely to proceed. Since the influence of light is reduced, it has bright display quality and excellent light resistance (high reliability). For example, a projection display device, a projection type HUD (head-up display), a direct-view type HMD (head-mounted display), an electronic book, a personal computer, a digital still camera, a liquid crystal television, a viewfinder type or a monitor direct-view type video recorder The electro-optical device described in the application example can be applied to an electronic terminal device such as an information terminal device such as a car navigation system, a POS, or an electronic notebook.

(A) is a schematic plan view which shows the structure of the liquid crystal device which concerns on Embodiment 1, (b) is a schematic sectional drawing cut | disconnected by the H-H 'line | wire of (a). FIG. 3 is an equivalent circuit diagram illustrating an electrical configuration of the liquid crystal device according to the first embodiment. The schematic plan view which shows arrangement | positioning of a pixel. (A) is a schematic plan view which shows arrangement | positioning of the thin-film transistor and signal line in a pixel, (b) is a schematic plan view which shows arrangement | positioning of the capacitive electrode and pixel electrode in a pixel. FIG. 5 is a schematic cross-sectional view illustrating the structure of a pixel cut along line A-A ′ in FIG. 4. FIG. 4 is a schematic cross-sectional view illustrating the structure of a pixel cut along line B-B ′ in FIG. 3. The schematic diagram which shows the course of the light which permeate | transmits an opening area | region. Spectral characteristics when the film thickness of the pixel electrode and the film thickness of the capacitor electrode are changed with the same film thickness. Spectral characteristics when the thickness of the pixel electrode is 140 nm and the thickness of the capacitor electrode is changed from 140 nm to 182 nm. Spectral characteristics when the thickness of the pixel electrode is 140 nm and the thickness of the capacitor electrode is changed from 140 nm to 98 nm. Spectral characteristics when the thickness of the capacitor electrode is 140 nm and the thickness of the pixel electrode is changed from 140 nm to 182 nm. Spectral characteristics when the thickness of the capacitor electrode is 140 nm and the thickness of the pixel electrode is changed from 140 nm to 98 nm. Spectral characteristics when one of the pixel electrode or the capacitor electrode is thinner than 140 nm and the other is thicker than 140 nm. Schematic which shows the structure of the projection type display apparatus as an electronic device.

  Embodiments of the present invention will be described below with reference to the drawings. Such embodiment shows one mode of the present invention, does not limit the present invention, and can be arbitrarily changed within the scope of the technical idea of the present invention. In each of the following drawings, the scale of each layer or each part is made different from the actual scale so that each layer or each part can be recognized on the drawing.

(Embodiment 1)
"Outline of LCD device"
The liquid crystal device 100 according to the first embodiment is an example of an electro-optical device, and is a transmissive liquid crystal device including a thin film transistor (hereinafter referred to as TFT) 30. The liquid crystal device 100 according to the present embodiment can be suitably used as, for example, a light modulation element of a projection display device (liquid crystal projector) described later.

First, the overall configuration of the liquid crystal device 100 according to the present embodiment will be described with reference to FIGS. 1 and 2.
1A is a schematic plan view showing the configuration of the liquid crystal device, FIG. 1B is a schematic cross-sectional view taken along line HH ′ of FIG. 1A, and FIG. 2 is an electrical configuration of the liquid crystal device. FIG.

  As shown in FIGS. 1A and 1B, the liquid crystal device 100 includes an element substrate 10 and a counter substrate 20 that are arranged to face each other, and a liquid crystal layer 50 that is sandwiched between the pair of substrates.

  The element substrate 10 is slightly larger than the counter substrate 20. The element substrate 10 and the counter substrate 20 are bonded via a seal material 40 arranged in a frame shape, and liquid crystal having positive or negative dielectric anisotropy is sealed in the gap to form a liquid crystal layer 50. Yes. For the sealing material 40, for example, an adhesive such as a thermosetting or ultraviolet curable epoxy resin is employed. A spacer (not shown) is mixed in the sealing material 40 to keep the distance between the pair of substrates constant.

  A light shielding film 21 is similarly provided in a frame shape inside the sealing material 40 arranged in a frame shape. The light shielding film 21 is made of, for example, a light shielding metal or metal oxide, and the inside of the light shielding film 21 is a display region E. In the display area E, a plurality of pixels P are arranged in a matrix. The display area E may include a plurality of dummy pixels arranged so as to surround a plurality of effective pixels P that contribute to display. Although not shown in FIG. 1, the display area E is also provided with a light-shielding portion that divides a plurality of pixels P in a plane.

A data line driving circuit 101 is provided between one side portion on which the plurality of external connection terminals 104 of the element substrate 10 are arranged and the sealing material 40 along the one side portion. Further, an inspection circuit 103 is provided inside the sealing material 40 along the other one side facing the one side. Further, a scanning line driving circuit 102 is provided inside the sealing material 40 along the other two sides orthogonal to the one side and facing each other. A plurality of wirings 105 that connect the two scanning line driving circuits 102 are provided inside the sealing material 40 on the other side facing the one side. Wirings connected to the data line driving circuit 101 and the scanning line driving circuit 102 are connected to a plurality of external connection terminals 104 arranged along the one side.
Hereinafter, the direction along the one side is the X direction, the direction along the other two sides orthogonal to the one side and facing each other is the Y direction, and the direction from the element substrate 10 toward the counter substrate 20 is Z. This will be described as a direction.

As shown in FIG. 1B, the element substrate 10 includes an element substrate main body 10a, and a thin film transistor (hereinafter referred to as TFT) 30 formed on the surface of the element substrate main body 10a on the liquid crystal layer 50 side. The pixel electrode 15 and the alignment film 18 that covers the pixel electrode 15 are included. The element substrate body 10a is made of a transparent material such as quartz or glass. The TFT 30 and the pixel electrode 15 are components of the pixel P, and the pixels P are arranged in a matrix in the X direction and the Y direction. Details of the pixel P will be described later.
The element substrate main body 10a is an example of the “substrate” in the present invention.

The counter substrate 20 includes a counter substrate body 20a, a light shielding film 21, an interlayer insulating film 22, a counter electrode 23, an alignment film 24, and the like, which are sequentially stacked on the surface of the counter substrate body 20a on the liquid crystal layer 50 side. .
The counter substrate body 20a is made of a transparent material such as quartz or glass.

  As shown in FIG. 1A, the light shielding film 21 is provided in a frame shape at a position overlapping the data line driving circuit 101, the scanning line driving circuit 102, and the inspection circuit 103 in plan view. Thus, the light incident from the counter substrate 20 side is shielded, and the malfunction of the peripheral circuits including these drive circuits due to the light is prevented. Further, unnecessary stray light is shielded from entering the display area E, and high contrast in the display of the display area E is ensured.

  The interlayer insulating film 22 is made of an inorganic material such as silicon oxide, for example, and is provided so as to cover the light shielding film 21 with light transmittance. In addition, the interlayer insulating film 22 also functions as a planarizing layer that relaxes unevenness generated on the substrate by the light shielding film 21. As a method for forming the interlayer insulating film 22, for example, a method of forming a film using a plasma CVD method or the like can be given.

  The counter electrode 23 is made of a transparent conductive film such as ITO, for example, covers the interlayer insulating film 22 and is formed over the display region E. The counter electrode 23 is electrically connected to the wiring on the element substrate 10 side by vertical conduction portions 106 provided at the four corners of the counter substrate 20 as shown in FIG.

  The alignment film 18 that covers the pixel electrode 15 and the alignment film 24 that covers the counter electrode 23 are set based on the optical design of the liquid crystal device 100. In this embodiment, an obliquely deposited film (inorganic film) of an inorganic material such as silicon oxide is used. Alignment film). The alignment films 18 and 24 may be organic alignment films such as polyimide.

  As shown in FIG. 2, the liquid crystal device 100 extends in parallel to the scanning lines 3 a and a plurality of scanning lines 3 a and a plurality of data lines 6 a as signal lines that are insulated and orthogonal to each other at least in the display region E. Capacitance line 3b.

  A pixel electrode 15, a TFT 30, and a storage capacitor 17 are provided in an area divided by the scanning line 3a and the data line 6a, and these constitute a pixel circuit of the pixel P.

  The scanning line 3 a is electrically connected to the gate of the TFT 30, and the data line 6 a is electrically connected to the source of the TFT 30. The pixel electrode 15 is electrically connected to the drain of the TFT 30.

  The data line 6a is connected to the data line driving circuit 101 (see FIG. 1), and supplies image signals D1, D2,..., Dn supplied from the data line driving circuit 101 to the pixels P. The scanning line 3a is connected to a scanning line driving circuit 102 (see FIG. 1), and supplies scanning signals SC1, SC2,..., SCm supplied from the scanning line driving circuit 102 to each pixel P. The image signals D1 to Dn supplied from the data line driving circuit 101 to the data lines 6a may be supplied line-sequentially in this order, or may be supplied for each of a plurality of adjacent data lines 6a for each group. Good. The scanning line driving circuit 102 supplies the scanning signals SC1 to SCm to the scanning line 3a in a pulse-sequential manner at a predetermined timing.

  In the liquid crystal device 100, the TFT 30 that is a switching element is turned on for a certain period by the input of the scanning signals SC1 to SCm, so that the image signals D1 to Dn supplied from the data line 6a are supplied to the pixel electrode 15 at a predetermined timing. It is the structure written in. The predetermined level of image signals D1 to Dn written to the liquid crystal layer 50 through the pixel electrode 15 are held for a certain period between the pixel electrode 15 and the counter electrode 23 arranged to face each other through the liquid crystal layer 50. The

  In order to prevent the retained image signals D1 to Dn from leaking, a storage capacitor 17 is connected in parallel with the liquid crystal capacitor formed between the pixel electrode 15 and the counter electrode 23. The storage capacitor 17 is provided between the drain of the TFT 30 and the capacitor line 3b. As will be described in detail later, one of the pair of translucent electrodes constituting the storage capacitor 17 functions as the capacitor line 3b.

  Note that a data line 6a is connected to the inspection circuit 103 shown in FIG. 1A, and an operation defect or the like of the liquid crystal device 100 is confirmed by detecting the image signal in the manufacturing process of the liquid crystal device 100. Although it can be configured, it is omitted in the equivalent circuit of FIG. The inspection circuit 103 includes a sampling circuit that samples the image signal and supplies it to the data line 6a, and a precharge circuit that supplies a precharge signal of a predetermined voltage level to the data line 6a prior to the image signal. Also good.

  Such a liquid crystal device 100 is a transmission type, and the transmittance of the pixel P when the voltage is not applied is larger than the transmittance when the voltage is applied, and a normally white mode where a bright display is obtained, or when no voltage is applied. The normally black mode optical design is adopted in which the transmittance of the pixel P is smaller than the transmittance at the time of voltage application and dark display is achieved. Depending on the optical design, polarizing elements (not shown) are respectively used on the light incident side and the light emitting side.

"Pixel overview"
Next, an outline of the pixel P will be described with reference to FIGS.
3 is a schematic plan view showing the arrangement of pixels in the liquid crystal device, FIG. 4A is a schematic plan view showing the arrangement of thin film transistors and signal lines in the pixel, and FIG. 3B is a capacitor constituting a storage capacitor in the pixel. 5 is a schematic plan view showing the arrangement of electrodes and pixel electrodes, FIG. 5 is a schematic cross-sectional view showing the structure of the pixel cut along line AA ′ in FIG. 4, and FIG. 6 is a pixel cut along line BB ′ in FIG. It is a schematic sectional drawing which shows this structure.

  As shown in FIG. 3, the pixel P in the liquid crystal device 100 has, for example, a substantially quadrangular (substantially square) opening region in a plan view. The opening area is surrounded by a light-shielding non-opening area extending in the X direction and the Y direction and provided in a lattice shape.

  A scanning line 3a shown in FIG. 2 is provided in the non-opening region extending in the X direction. The scanning line 3a uses a light-shielding conductive member, and at least a part of the non-opening region is constituted by the scanning line 3a.

  Similarly, a data line 6a shown in FIG. 2 is provided in the non-opening region extending in the Y direction. The data line 6a also uses a light-shielding conductive member, and at least a part of the non-opening region is constituted by these.

  The non-opening region is formed not only by the signal lines provided on the element substrate 10 side, but also by a light shielding film 21 patterned in a lattice pattern on the counter substrate 20 side.

  The TFT 30 shown in FIG. 2 is provided near the intersection of the non-opening regions. By providing the TFT 30 in the vicinity of the intersection of the non-opening region having the light shielding property, the optical malfunction of the TFT 30 is prevented and the aperture ratio in the opening region is secured. Although the detailed structure of the pixel P will be described later, the width of the non-opening region in the vicinity of the intersecting portion is wider than that in other portions due to the provision of the TFT 30 near the intersecting portion.

Next, each component such as a thin film transistor in the pixel circuit of the pixel P will be described with reference to FIGS.
As shown in FIG. 4, the pixel P includes a TFT 30 provided at the intersection of the scanning line 3a and the data line 6a. The TFT 30 includes a data line side source / drain region 30s, a channel region 30c, a pixel electrode side source / drain region 30d, and a junction region 30e provided between the data line side source / drain region 30s and the channel region 30c. And a semiconductor layer 30a having an LDD (Lightly Doped Drain) structure having a junction region 30f provided between the channel region 30c and the pixel electrode side source / drain region 30d. The semiconductor layer 30a is disposed so as to pass through the intersection and overlap the scanning line 3a.

  The scanning line 3a has a quadrangular extended portion in a plan view extended in the X and Y directions at the intersection with the data line 6a. A bent gate electrode 30g having an opening that overlaps the extension portion in plan and does not overlap with the junction region 30f and the pixel electrode side source / drain region 30d is provided.

  In the gate electrode 30g, the portion extending in the Y direction overlaps the channel region 30c in a plane. Further, the scanning lines 3a and CNT4 are bent by contact holes CNT3 and CNT4 that are bent from the portion overlapping the channel region 30c and extend in the X direction, and the portions facing each other are provided between the extended portions of the scanning line 3a. Electrically connected.

  The contact holes CNT3 and CNT4 are rectangular (rectangular) having a long X direction in plan view, and are provided on both sides so as to sandwich the junction region 30f along the channel region 30c and the junction region 30f of the semiconductor layer 30a. Yes.

  The data line 6a extends in the Y direction and also has a rectangular extension at the intersection with the scanning line 3a, and is formed by a contact hole CNT1 provided in the protrusion 6c protruding from the extension in the X direction. It is electrically connected to the data line side source / drain region 30s. A portion including the contact hole CNT1 is a source electrode 31. On the other hand, the contact hole CNT2 is also provided at the end of the pixel electrode side source / drain region 30d, and the portion including the contact hole CNT2 serves as the drain electrode 32.

  Contact holes CNT5 and CNT7 are provided adjacent to the contact hole CNT2 in the extending direction (X direction) of the scanning line 3a. The contact hole CNT2 and the contact hole CNT5 are electrically connected via a first relay electrode 6b provided in an island shape. The contact hole CNT5 and the contact hole CNT7 are electrically connected through the second relay electrode 7b provided in the same island shape.

  As shown in FIG. 4B, the pixel electrode 15 is arranged so as to overlap the above-described opening region (see FIG. 3) in a plan view and the outer edge portion covers the non-opening region (see FIG. 3). Further, the pixel electrode 15 has a protrusion 15a for electrical connection with the contact hole CNT7. That is, the pixel electrode 15 has a substantially rectangular (substantially square) island shape provided for each pixel P.

  The capacitor electrode 16 is made of a translucent material and is provided so as to straddle a plurality of pixels P arranged in a matrix in the X direction and the Y direction. The capacitor electrode 16 overlaps with the pixel electrode 15 in each pixel P in plan view, and constitutes a storage capacitor 17. The capacitor electrode 16 has an opening 16ch in a portion overlapping with the second relay electrode 7b so that the pixel electrode 15 and the capacitor electrode 16 do not contact with each other through the contact hole CNT7. The capacitor electrode 16 is provided so as to extend over the display region E, and also has a function of the capacitor line 3b (see FIG. 2) common to the plurality of pixels P. A part of the capacitor electrode 16 is drawn outside the display area E and is electrically connected to a wiring to which a fixed potential is supplied.

  As shown in FIG. 5, the scanning line 3a is first formed on the element substrate body 10a. The scanning line 3a also serves as a light-shielding film that shields the semiconductor layer 30a. For example, the scanning line 3a includes a metal simple substance including at least one of metals such as Al, Ti, Cr, W, Ta, and Mo, an alloy, a metal silicide, Silicide, nitride, or a laminate of these can be used and has light shielding properties.

  A base insulating film 9 made of, for example, silicon oxide or the like is formed so as to cover the scanning line 3a, and a semiconductor layer 30a is formed on the base insulating film 9 in an island shape. The semiconductor layer 30a is made of, for example, a polycrystalline silicon film, and is implanted with impurity ions, and the data line side source / drain region 30s, the junction region 30e, the channel region 30c, the junction region 30f, and the pixel electrode side source / drain region 30d described above. An LDD structure having is formed.

  A first insulating film (gate insulating film) 11a made of, for example, silicon oxide is formed so as to cover the semiconductor layer 30a. Further, a gate electrode 30g is formed at a position facing the channel region 30c with the first insulating film 11a interposed therebetween. The gate electrode 30g can be formed using, for example, a polycrystalline silicon film, and at the same time, penetrates the base insulating film 9 and the first insulating film 11a to electrically connect the scanning line 3a (extended portion) and the gate electrode 30g. Contact holes CNT3 and CNT4 (see FIG. 4) to be connected are also formed.

  A second insulating film 11b made of, for example, silicon oxide is formed so as to cover the gate electrode 30g and the first insulating film 11a. A contact hole CNT1 penetrating through the first insulating film 11a and the second insulating film 11b overlapping the data line side source / drain region 30s of the semiconductor layer 30a is formed. Similarly, a contact hole CNT2 penetrating the first insulating film 11a and the second insulating film 11b overlapping the pixel electrode side source / drain region 30d of the semiconductor layer 30a is formed. Subsequently, a conductive film made of a light-shielding metal such as Al is formed and patterned so as to cover the second insulating film 11b, whereby the data line side source / drain region 30s is electrically connected to the data line side source / drain region 30s via the contact hole CNT1. Connected data lines 6a are formed. At the same time, the first relay electrode 6b electrically connected to the pixel electrode side source / drain region 30d through the contact hole CNT2 is formed.

  Subsequently, the first interlayer insulating film 12 is formed so as to cover the data line 6a and the first relay electrode 6b. The first interlayer insulating film 12 is made of, for example, silicon oxide, nitride, or oxynitride, and is subjected to a flattening process for flattening the surface unevenness caused by covering the region where the TFT 30 is provided. Examples of the planarization method include chemical mechanical polishing (CMP) and spin coating.

A contact hole CNT5 penetrating the first interlayer insulating film 12 is formed at a position overlapping the first relay electrode 6b. A conductive film made of a light-shielding metal such as Al is formed so as to cover the contact hole CNT5 and cover the first interlayer insulating film 12, and the wiring 7a and the contact hole CNT5 are formed by patterning the conductive film. And a second relay electrode 7b electrically connected to the first relay electrode 6b.
The wiring 7a is formed so as to overlap with the semiconductor layer 30a and the data line 6a of the TFT 30 in a plan view, and functions as a shield layer when given a fixed potential.

  A second interlayer insulating film 13 is formed so as to cover the wiring 7a and the second relay electrode 7b. The second interlayer insulating film 13 can also be formed using, for example, silicon oxide, nitride, or oxynitride, and is subjected to a planarization process such as a CMP process.

  Next, a transparent conductive film such as, for example, ITO is formed so as to cover the second interlayer insulating film 13, and by patterning this, a capacitor electrode 16 that functions as the capacitor line 3b is formed. As described above, the capacitor electrode 16 is formed over the display region E including at least the plurality of pixels P, and the opening 16ch is formed in a portion overlapping the second relay electrode 7b in a plan view.

  Next, the dielectric layer 14 is formed so as to cover the capacitor electrode 16. The dielectric layer 14 is a multilayer film in which a first dielectric film (not shown) and a second dielectric film (not shown) are alternately stacked.

The first dielectric film is hafnium oxide (HfO ₂ ), and the second dielectric film is aluminum oxide (Al ₂ O ₃ ). The dielectric layer 14 includes hafnium oxide (first dielectric film), aluminum oxide (second dielectric film), hafnium oxide (first dielectric film), and aluminum oxide (second dielectric film). Film) and hafnium oxide (first dielectric film) are sequentially stacked. Hafnium oxide has a feature that the dielectric constant is large, and aluminum oxide has a feature that leakage current is small. By forming the dielectric layer 14 to have a laminated structure of hafnium oxide and aluminum oxide, a capacitor element (storage capacitor 17) having a large capacitance density, low leakage current, and excellent withstand voltage can be formed.
As a material constituting the dielectric layer 14, a silicon nitride film, tantalum oxide (Ta ₂ O ₅ ) or the like can be used in addition to hafnium oxide and aluminum oxide. The dielectric layer 14 is not limited to the five-layer structure of the present embodiment, and the number of stacked layers may be larger or smaller than this.

  The film thickness of the dielectric layer 14 is 20 nm to 50 nm in consideration of electric capacity. The dielectric layer 14 is such an extremely thin thin film and has high transparency with respect to visible light. That is, if the film thickness of the dielectric layer 14 is 20 nm to 50 nm, transmission of visible light (light in the wavelength range of 400 nm to 800 nm) is inhibited even if the dielectric layer 14 has a number of five or more layers. The dielectric layer 14 is highly transparent to visible light.

Next, a contact hole CNT7 that penetrates through the second interlayer insulating film 13 and the dielectric layer 14 is formed at a position overlapping the second relay electrode 7b. Then, a transparent conductive film such as ITO is formed to cover the contact hole CNT7 and cover the dielectric layer 14, and by patterning this, the second relay electrode 7b is electrically connected to the contact hole CNT7 through the contact hole CNT7. A pixel electrode 15 to be connected is formed.
The pixel electrode 15 overlaps the capacitor electrode 16 in a plan view, and a translucent storage capacitor 17 is formed for each pixel P by the pixel electrode 15, the dielectric layer 14, and the capacitor electrode 16. The alignment film 18 covers the entire display area E and is composed of the above-described inorganic alignment film such as silicon oxide.

  According to such a wiring structure of the element substrate 10, the drain electrode 32 of the TFT 30 is electrically connected to the pixel electrode 15 through the first relay electrode 6b, the contact hole CNT5, the second relay electrode 7b, and the contact hole CNT7. Is done.

  As shown in FIG. 6, in the opening area of the pixel P, the base insulating film 9, the first insulating film 11a, and the second insulating film 11b are formed on the surface of the transparent element substrate body 10a on the liquid crystal layer 50 side. The first interlayer insulating film 12, the second interlayer insulating film 13, the translucent capacitive electrode 16, the dielectric layer 14, the pixel electrode 15, and the alignment film 18 are sequentially stacked.

  As described above, the base insulating film 9, the first insulating film 11a, the second insulating film 11b, the first interlayer insulating film 12, the second interlayer insulating film 13 and the like are made of silicon oxide (silicon oxide) or nitride. Therefore, it has substantially the same refractive index (1.4 to 1.5 in the visible light region) as that of the constituent material of the element substrate body 10a, for example, quartz. In this way, the constituent elements from the element substrate main body 10a to the second interlayer insulating film 13 of the element substrate 10 have substantially the same refractive index, so that visible light transmitted through these layers (films) Since it hardly reflects or refracts at the (film) interface, the intensity (transmittance) of the light is difficult to attenuate.

  On the other hand, in the portion above the second interlayer insulating film 13 (the portion where the storage capacitor 17 is formed), the second interlayer insulating film 13 (with a refractive index of 1.4 to 1.5 in the visible light region) And capacitive electrode 16 (if ITO, the refractive index is 1.5 to 1.9 in the visible light region), and dielectric layer 14 (refractive index in the visible light region is 1.9 to 2.0 (hafnium oxide)), The pixel electrode 15 (with ITO having a refractive index of 1.5 to 1.9 in the visible light region) and the alignment film 18 (with a refractive index of 1.4 to 1.5 (silicon oxide)) are stacked. As described above, the constituent elements from the second interlayer insulating film 13 to the alignment film 18 of the element substrate 10 include the transparent conductive film (pixel electrode 15 and capacitor electrode 16) constituting the storage capacitor 17. It has a structure sandwiched between translucent thin films having different refractive indexes (second interlayer insulating film 13, dielectric layer 14, and alignment film 18). Light reflection (multiple reflection) occurs between the bright conductive film and the translucent thin film, and the light reflected between the transparent conductive film and the translucent thin film and the transparent conductive film. The light transmitted through the transparent conductive film interferes (multiple interference), and the transmittance (brightness) of the light transmitted through the transparent conductive film fluctuates due to the transparent conductive film (pixel electrode 15 and capacitor electrode 16). Depending on the optical path length (film thickness × refractive index), the wavelength of light, and the like.

  For example, depending on the wavelength of the light transmitted through the pixel electrode 15 and the capacitor electrode 16, the light transmitted through the pixel electrode 15 and the capacitor electrode 16 is attenuated by the interference between the reflected light and the transmitted light (transmittance). May decrease). Further, depending on the wavelength of the light transmitted through the pixel electrode 15 and the capacitor electrode 16, the light transmitted through the pixel electrode 15 and the capacitor electrode 16 is amplified by the interference between the reflected light and the transmitted light (transmittance). May increase).

"Required spectral characteristics (target performance)"
Next, an outline of spectral characteristics (target performance) required for the liquid crystal device 100 (element substrate 10) will be described with reference to FIG.
FIG. 7 is a schematic diagram showing a path of light transmitted through the opening region shown in FIG. In the figure, an arrow with a symbol K1 indicates light emitted from a light source (not shown) and incident on the element substrate 10, and is hereinafter referred to as incident light K1. An arrow with a symbol K2 indicates light that passes through the element substrate 10 (storage capacitor 17) and is emitted from the element substrate 10, and is hereinafter referred to as emitted light K2. The arrow with the symbol K3 indicates the light reflected by the storage capacitor 17 (pixel electrode 15 and capacitor electrode 16), and is hereinafter referred to as reflected light K2.

  As shown in FIG. 7, the light K <b> 1 emitted from the light source travels in the Z (−) direction, that is, from the counter substrate 20 toward the element substrate 10. Incident light I incident on the element substrate 10 is divided into outgoing light K2 that passes through the element substrate 10, reflected light K3 that is reflected by the storage capacitor 17, and absorbed light that is absorbed in the element substrate 10. Since the light absorbed in the element substrate 10 is weak, it can be considered that the incident light K1 is divided into the outgoing light K2 and the reflected light K3.

  The emitted light K2 is transmitted through the liquid crystal device 100 and becomes display light contributing to display. When the luminance of the outgoing light K2 is increased, a bright display is obtained. Therefore, it is preferable that the luminance of the outgoing light K2 is higher. On the other hand, the reflected light K3 is light that does not contribute to display, passes through the alignment films 18 and 24 and the liquid crystal layer 50, and travels in the Z (+) direction, that is, from the element substrate 10 toward the counter substrate 20. Since the reflected light K3 may cause deterioration (light deterioration) of the alignment films 18 and 24 and the liquid crystal layer 50, it is preferable that the brightness of the reflected light K3 is small. Further, the luminance of the emitted light K2 and the luminance of the reflected light K3 are in a trade-off relationship. Specifically, there is a relationship that the luminance of the outgoing light K2 increases as the luminance of the reflected light K3 decreases.

  As described above, the luminance (transmittance) of the emitted light K2 varies depending on the film thickness of the pixel electrode 15, the film thickness of the capacitor electrode 16, the wavelength of the incident light K1, and the like. In the entire wavelength range of the incident light K1, it is difficult to increase the luminance of the outgoing light K2, and it is necessary to optimize the spectral characteristics of the liquid crystal device 100 according to the use of the liquid crystal device 100.

  The liquid crystal device 100 of the present embodiment is a light modulation element (light valve) that can be suitably used for a liquid crystal projector described later. In the liquid crystal projector, light in a blue wavelength range (400 nm to 500 nm), green wavelength range (500 nm to 600 nm), and red wavelength range (600 nm to 700 nm) is emitted from a light source as a light modulation element. Is incident on the liquid crystal device 100. The liquid crystal device 100 as a light modulation element is required to have performances such as providing a brighter display and being less likely to deteriorate as a light modulation element even when exposed to strong light (light resistance). The Therefore, in the present embodiment, the spectral characteristics of the liquid crystal device 100 are optimized with the following items as target performance.

  1) Increasing the luminance (light transmittance) of light in a wavelength range that is highly sensitive to human visibility characteristics, specifically, emitted light K2 in the wavelength range of 530 nm to 590 nm. Light in a wavelength range having high sensitivity in human visibility characteristics has the most influence on the brightness of display, and a bright display can be obtained by increasing the transmittance of light in this wavelength range.

  2) Increasing the transmittance of light in a short wavelength range that easily affects the alignment films 18 and 24 and the liquid crystal layer 50, specifically light in the wavelength range of 400 nm to 460 nm, and reflected light K3 in the wavelength range of 400 nm to 460 nm. To weaken. When the reflected light K3 in the wavelength range of 400 nm to 460 nm is weakened, the alignment films 18 and 24 and the liquid crystal layer 50 are not easily deteriorated by the reflected light K3, and the light resistance is improved.

  In this embodiment, prototype storage and optical simulation are repeated, and the storage capacitor 17 is configured so that the transmittance of light in the wavelength range of 530 nm to 590 nm and the transmittance of light in the wavelength range of 400 nm to 460 nm are increased. The film thickness of the pixel electrode 15 and the capacitor electrode 16 to be optimized was attempted. That is, by repeating trial experiments and optical simulations, the transmittance increases in the spectral distribution of light transmitted through the element substrate body 10a and the storage capacitor 17 in the wavelength range of 530 nm to 590 nm and in the wavelength range of 400 nm to 460 nm. The film thickness of the pixel electrode 15 and the capacitor electrode 16 was optimized so as to have a peak. Then, as a result of repeating prototype experiments and optical simulations, the inventors have found a condition for forming a peak in which the transmittance is stably increased in each of a wavelength range of 530 nm to 590 nm and a wavelength range of 400 nm to 460 nm.

"Preferable conditions for pixel electrode and capacitor electrode"
Next, preferred conditions of the pixel electrode 15 and the capacitor electrode 16 will be described with specific examples and comparative examples.

Example 1
In Example 1, the pixel electrode 15 and the capacitor electrode 16 are made of ITO, the film thickness of the pixel electrode 15 is 140 nm, and the film thickness of the capacitor electrode 16 is 140 nm.

(Example 2)
In the second embodiment, the pixel electrode 15 and the capacitor electrode 16 are made of ITO. The film thickness of the capacitor electrode 16 is 10% (14 nm) thicker than that of the first embodiment, and is set to 154 nm.

(Example 3)
In Example 3, the pixel electrode 15 and the capacitor electrode 16 are made of ITO, and the film thickness of the capacitor electrode 16 is 10% (14 nm) thinner than that of Example 1 and set to 126 nm.

Example 4
In Example 4, the pixel electrode 15 and the capacitor electrode 16 are made of ITO, and the film thickness of the pixel electrode 15 is 10% (14 nm) thicker than that of Example 1, and is set to 154 nm.

(Example 5)
In the fifth embodiment, the pixel electrode 15 and the capacitor electrode 16 are made of ITO. The film thickness of the pixel electrode 15 is 10% (14 nm) thinner than that of the first embodiment and is set to 126 nm.

(Example 6)
In the sixth embodiment, the pixel electrode 15 and the capacitor electrode 16 are made of ITO, and the film thickness of the pixel electrode 15 is reduced by 10% (14 nm) to 126 nm compared to the first embodiment. The thickness was increased to 10% (14 nm) and set to 154 nm.

(Example 7)
In the seventh embodiment, the pixel electrode 15 and the capacitor electrode 16 are made of ITO, and the film thickness of the pixel electrode 15 is set to 154 nm by increasing the film thickness of the pixel electrode 15 by 10% (14 nm) compared to the first embodiment. The thickness is reduced by 10% (14 nm) and set to 126 nm.

(Comparative Example 1)
In Comparative Example 1, the film thickness of the pixel electrode 15 and the capacitor electrode 16 is set to 100 nm by reducing the film thickness of the pixel electrode 15 and the capacitor electrode 16 by approximately 29% (40 nm).

(Comparative Example 2)
In Comparative Example 2, the film thickness of the pixel electrode 15 and the capacitor electrode 16 is set to 120 nm by reducing the film thickness of the pixel electrode 15 and the capacitor electrode 16 by about 14% (20 nm).

(Comparative Example 3)
In Comparative Example 3, the film thickness of the pixel electrode 15 and the capacitor electrode 16 is set to 160 nm by increasing the film thickness of the pixel electrode 15 and the capacitor electrode 16 by about 14% (20 nm).

(Comparative Example 4)
In Comparative Example 4, compared to Example 1, the film thickness of the pixel electrode 15 and the capacitor electrode 16 is set to 180 nm by increasing the film thickness by approximately 29% (40 nm).

(Comparative Example 5)
In Comparative Example 5, compared with Example 1, the thickness of the capacitor electrode 16 is set to 168 nm by increasing the film thickness by approximately 20% (28 nm).

(Comparative Example 6)
In Comparative Example 6, compared to Example 1, the thickness of the capacitor electrode 16 is set to 182 nm by increasing the film thickness by approximately 30% (42 nm).

(Comparative Example 7)
In Comparative Example 7, the thickness of the capacitor electrode 16 is set to 112 nm by reducing the film thickness of the capacitive electrode 16 by about 20% (28 nm).

(Comparative Example 8)
In Comparative Example 8, the film thickness of the capacitive electrode 16 is set to 98 nm by reducing the film thickness of the capacitive electrode 16 by about 30% (42 nm).

(Comparative Example 9)
In Comparative Example 9, the film thickness of the pixel electrode 15 is set to 168 nm by increasing the film thickness of the pixel electrode 15 by about 20% (28 nm).

(Comparative Example 10)
In Comparative Example 10, compared to Example 1, the film thickness of the pixel electrode 15 is set to 182 nm by increasing the thickness by approximately 30% (42 nm).

(Comparative Example 11)
In Comparative Example 11, compared with Example 1, the film thickness of the pixel electrode 15 is reduced by about 20% (28 nm) and set to 112 nm.

(Comparative Example 12)
In Comparative Example 12, compared to Example 1, the film thickness of the pixel electrode 15 is reduced by about 30% (42 nm) and set to 98 nm.

  Hereinafter, with reference to FIGS. 8 to 13, preferred examples of the pixel electrode 15 and the capacitor electrode 16 in Examples 1 to 7 and Comparative Examples 1 to 12 will be described.

FIG. 8 shows the spectral characteristics of the liquid crystal devices related to Example 1 and Comparative Examples 1 to 4, where (a) is a graph showing the spectral distribution, and (b) is the peak wavelength at which the transmittance increases. It is a table | surface which shows (henceforth a peak wavelength). FIG. 9 shows the spectral characteristics of the liquid crystal devices related to Example 1, Example 2, Comparative Example 5 and Comparative Example 6, (a) is a graph showing the spectral distribution, and (b) shows the peak wavelength. It is a table. FIG. 10 shows the spectral characteristics of the liquid crystal devices related to Example 1 and Example 3, and Comparative Example 7 and Comparative Example 8, (a) is a graph showing the spectral distribution, and (b) shows the peak wavelength. It is a table. FIG. 11 shows the spectral characteristics of the liquid crystal devices related to Example 1, Example 4, and Comparative Example 9 and Comparative Example 10, where (a) is a graph showing the spectral distribution and (b) shows the peak wavelength. It is a table. FIG. 12 shows the spectral characteristics of the liquid crystal devices related to Example 1, Example 5 and Comparative Example 11 Comparative Example 12, (a) is a graph showing the spectral distribution, and (b) is a table showing the peak wavelength. It is. FIG. 13 shows spectral characteristics of the liquid crystal devices related to Example 1, Example 6, and Example 7, (a) is a graph showing the spectral distribution, and (b) is a table showing the peak wavelength. .
8 to 13, the peak wavelength 1 indicates the peak wavelength observed in the wavelength range of 400 nm to 500 nm, and the peak wavelength 2 indicates the peak wavelength observed in the wavelength range of 500 nm to 700 nm.

8 to 13, the spectral distribution of light (transmitted light K2) transmitted through the aperture region obtained by optical simulation with respect to Examples 1 to 7 and Comparative Examples 1 to 12 is a graph. It has become. In addition, the vertical axis of the graphs showing the spectral distributions in FIGS. 8 to 13 indicates the transmittance, and the maximum value of the transmittance is indexed as 1.
It should be noted that components of the element substrate 10 from the element substrate body 10a to the second interlayer insulating film 13 (element substrate body 10a, base insulating film 9, first insulating film 11a, second insulating film 11b, first interlayer insulating film 12). The second interlayer insulating film 13) is transparent to light in the visible light range (400 nm to 800 nm), and has different refractive indexes in the constituent elements from the second interlayer insulating film 13 to the alignment film 18 of the element substrate 10. An optical simulation of each example and each comparative example was performed on the assumption that light reflection occurs at the interface of the film (layer). In addition, prototypes corresponding to the film thickness configurations of the examples and comparative examples are prepared, and the spectral characteristics obtained by optical simulation and the measured spectral characteristics of the prototype match, that is, the validity of the simulation results. Has been confirmed.

  FIG. 8 shows spectral characteristics when the film thickness of the pixel electrode 15 and the film thickness of the capacitor electrode 16 are changed with the same film thickness. As shown in FIG. 8, Example 1 has peaks at which transmittance increases at 430 nm and 560 nm. That is, in Example 1, the liquid crystal device 100 has a peak in which the transmittance increases in each of the wavelength range of 530 nm to 590 nm and the wavelength range of 400 nm to 460 nm. In contrast, the peak wavelength of Comparative Example 1 is 440 nm, the peak wavelength of Comparative Example 2 is 500 nm, the peak wavelengths of Comparative Example 3 are 470 nm and 620 nm, and the peak wavelength of Comparative Example 4 is Are 500 nm and 680 nm. In either case, at least one of the wavelength range of 530 nm to 590 nm and the wavelength range of 400 nm to 460 nm does not have a peak in which the transmittance increases.

In particular, the liquid crystal device 100 according to the first embodiment has a peak in which the transmittance increases near the wavelength of light (555 nm) at which the human eye has the highest sensitivity in a bright environment, that is, realizes a bright display. Therefore, it has particularly excellent spectral characteristics. Furthermore, the liquid crystal device 100 according to Example 1 has a peak in which the transmittance increases even in the wavelength range of light that easily affects the deterioration of the alignment films 18 and 24 and the liquid crystal layer 50, and the alignment films 18 and 24 and the liquid crystal layer Since the reflected light K3 that deteriorates 50 is weakened, the alignment films 18 and 24 and the liquid crystal layer 50 are not easily deteriorated by the reflected light K3, and have excellent light resistance.
As described above, Example 1 achieves a brighter display and superior light resistance as compared with Comparative Examples 1 to 4. Further, the first embodiment has particularly excellent spectral characteristics with respect to human visibility characteristics, and can realize brighter display.

FIG. 9 shows spectral characteristics when the thickness of the pixel electrode 15 is constant at 140 nm and the thickness of the capacitor electrode 16 is changed from 140 nm to 182 nm. As shown in FIG. 9, the peak wavelengths of Example 2 are 440 nm and 580 nm, the peak wavelengths of Comparative Example 5 are 450 nm and 600 nm, and the peak wavelengths of Comparative Example 6 are 460 nm and 630 nm. Thus, when the film thickness of the pixel electrode 15 is constant at 140 nm, the target performance is satisfied when the film thickness of the capacitor electrode 16 is in the range of 140 nm to 154 nm (Example 1, Example 2). On the other hand, when the film thickness of the capacitive electrode 16 is in the range of 168 nm to 182 nm, the target performance is not satisfied (Comparative Example 5 and Comparative Example 6).
Therefore, it is preferable that the pixel electrode 15 has a thickness of 140 nm and the capacitor electrode 16 has a thickness of 140 nm to 154 nm. In other words, if both the film thickness of the pixel electrode 15 and the film thickness of the capacitor electrode 16 are 140 nm, the variation range of the film thickness of the capacitor electrode 16 is allowed to + 10% (+14 nm).

FIG. 10 shows the spectral characteristics when the thickness of the pixel electrode 15 is 140 nm and the thickness of the capacitor electrode 16 is changed from 140 nm to 98 nm. As shown in FIG. 10, the peak wavelengths of Example 3 are 410 nm and 540 nm, the peak wavelengths of Comparative Example 7 are 400 nm and 520 nm, and the peak wavelength of Comparative Example 8 is 500 nm. Thus, when the film thickness of the pixel electrode 15 is constant at 140 nm, the target performance is satisfied when the film thickness of the capacitor electrode 16 is in the range of 126 nm to 140 nm (Examples 1 and 3). On the other hand, when the film thickness of the capacitive electrode 16 is in the range of 98 nm to 112 nm, the target performance is not satisfied (Comparative Example 7 and Comparative Example 8).
Therefore, it is preferable that the pixel electrode 15 has a thickness of 140 nm and the capacitor electrode 16 has a thickness of 126 nm to 140 nm. In other words, when the film thickness of the pixel electrode 15 and the film thickness of the capacitor electrode 16 are both 140 nm, the film thickness variation range of the capacitor electrode 16 is allowed to be −10% (−14 nm).

  9 and 10, the film thickness range of the capacitor electrode 16 is preferably 126 nm to 154 nm under the condition that the film thickness of the pixel electrode 15 is 140 nm. In other words, when the film thickness of the pixel electrode 15 and the film thickness of the capacitor electrode 16 are both 140 nm, the film thickness variation range of the capacitor electrode 16 is allowed to ± 10% (± 14 nm).

FIG. 11 shows spectral characteristics when the thickness of the capacitor electrode 16 is 140 nm and the thickness of the pixel electrode 15 is changed from 140 nm to 182 nm. As shown in FIG. 11, the peak wavelengths of Example 4 are 440 nm and 580 nm, the peak wavelengths of Comparative Example 9 are 450 nm and 600 nm, and the peak wavelengths of Comparative Example 10 are 460 nm and 620 nm. Thus, when the film thickness of the capacitor electrode 16 is constant at 140 nm, the target performance is satisfied when the film thickness of the pixel electrode 15 is in the range of 140 nm to 154 nm (Examples 1 and 4). On the other hand, when the film thickness of the pixel electrode 15 is in the range of 168 nm to 182 nm, the target performance is not satisfied (Comparative Example 9 and Comparative Example 10).
Therefore, the thickness of the capacitor electrode 16 is preferably 140 nm, and the thickness of the pixel electrode 15 is preferably in the range of 140 nm to 154 nm. In other words, when the film thickness of the pixel electrode 15 and the film thickness of the capacitor electrode 16 are both 140 nm, the film thickness variation range of the pixel electrode 15 is allowed to + 10% (+14 nm).

FIG. 12 shows spectral characteristics when the thickness of the capacitor electrode 16 is 140 nm and the thickness of the pixel electrode 15 is changed from 140 nm to 98 nm. As shown in FIG. 12, the peak wavelengths of Example 5 are 410 nm and 540 nm, the peak wavelength of Comparative Example 11 is 520 nm, and the peak wavelength of Comparative Example 12 is 500 nm. As described above, when the film thickness of the capacitor electrode 16 is constant 140 nm, the target performance is satisfied when the film thickness of the pixel electrode 15 is in the range of 126 nm to 140 nm (Examples 1 and 5). On the other hand, when the film thickness of the pixel electrode 15 is in the range of 98 nm to 112 nm, the target performance is not satisfied (Comparative Example 11 and Comparative Example 12).
Therefore, it is preferable that the pixel electrode 15 has a thickness of 140 nm and the capacitor electrode 16 has a thickness of 126 nm to 140 nm. In other words, when the film thickness of the pixel electrode 15 and the film thickness of the capacitor electrode 16 are both 140 nm, the film thickness variation range of the pixel electrode 15 is allowed to be −10% (−14 nm).

  From FIG. 11 and FIG. 12, when the film thickness of the capacitor electrode 16 is 140 nm, the film thickness range of the pixel electrode 15 is preferably 126 nm to 154 nm. In other words, when the film thickness of the pixel electrode 15 and the film thickness of the capacitor electrode 16 are both 140 nm, the film thickness variation range of the pixel electrode 15 is allowed to ± 10% (± 14 nm).

  As shown in FIGS. 10 and 12, when one of the pixel electrode 15 and the capacitor electrode 16 is changed to a film thickness (140 nm) of the first embodiment and the other is changed to a film thickness thinner than that of the first embodiment, the peak wavelength is It changes to the short wavelength side. As shown in FIGS. 9 and 11, when one of the pixel electrode 15 and the capacitor electrode 16 is changed to a film thickness (140 nm) of the first embodiment and the other is changed to a film thickness thicker than that of the first embodiment, the peak wavelength is It changes to the long wavelength side. For example, if one of the pixel electrode 15 and the capacitor electrode 16 is made thinner than the film thickness (140 nm) of the first embodiment and the other is made thicker than the film thickness (140 nm) of the first embodiment, the effect of reducing the film thickness and the film It becomes possible to offset the effect of increasing the thickness.

  FIG. 13 shows a condition in which one of the pixel electrode 15 and the capacitor electrode 16 is thinner than the film thickness (140 nm) of the first embodiment and the other is thicker than the film thickness (140 nm) of the first embodiment, that is, the sixth embodiment. The spectral characteristics of Example 7 are shown. Specifically, in Example 6, the pixel electrode 15 is 10% (14 nm) thinner than the film thickness (140 nm) of Example 1, and the capacitor electrode 16 is 10% of the film thickness (140 nm) of Example 1. (14 nm) This corresponds to the thickened condition. In Example 7, the capacitor electrode 16 was made 10% (14 nm) thinner than the film thickness (140 nm) of Example 1, and the pixel electrode 15 was made 10% (14 nm) thicker than the film thickness (140 nm) of Example 1. Corresponds to the conditions.

As shown in FIG. 13, the peak wavelengths of Example 1 are 430 nm and 560 nm, the peak wavelengths of Example 6 are 420 nm and 560 nm, and the peak wavelengths of Example 7 are 420 nm and 560 nm. Thus, the film thickness is reduced under the condition that one of the pixel electrode 15 and the capacitor electrode 16 is thinner than the film thickness (140 nm) of the first embodiment and the other is thicker than the film thickness (140 nm) of the first embodiment. The effect of increasing the film thickness and the effect of increasing the film thickness are offset, and the spectral characteristics substantially equivalent to those of Example 1 are obtained (Examples 6 and 7).
The liquid crystal devices 100 according to the sixth and seventh embodiments also have a peak in which the transmittance increases near the wavelength of light (555 nm) at which the human eye has the highest sensitivity in a bright environment, that is, a bright display. In particular, it has excellent spectral characteristics.

In summary, in the present embodiment, the following effects can be obtained.
1) When the film thickness of the pixel electrode 15 and the film thickness of the capacitor electrode 16 are both 140 nm, the liquid crystal device 100 is in the vicinity of the wavelength (555 nm) of light that provides the highest sensitivity for human eyes in a bright environment. It has a peak at which the transmittance increases, that is, it has particularly excellent spectral characteristics for realizing a bright display. Furthermore, even in the wavelength range (400 nm to 460 nm) of light that easily affects the alignment films 18, 24 and the liquid crystal layer 50, there is a peak in which the transmittance increases, and the reflected light K 3 in the wavelength range (400 nm to 460 nm) is weak. It has become. Therefore, it is difficult for the alignment films 18 and 24 and the liquid crystal layer 50 to deteriorate due to the reflected light K3 in the wavelength range (400 nm to 460 nm). Accordingly, it is possible to provide the liquid crystal device 100 which is excellent in light resistance and has a particularly bright display.

  2) When the pixel electrode 15 has a film thickness of 140 nm, the capacitive electrode 16 has a film thickness range of 126 nm to 154 nm, and the liquid crystal device 100 has a wavelength range of light (530 nm to 590 nm) with high human visibility characteristics. ) And the wavelength range (400 nm to 460 nm) of light that tends to cause deterioration of the alignment films 18, 24 and the liquid crystal layer 50. Therefore, it is possible to provide the liquid crystal device 100 which has excellent light resistance and a bright display.

  3) When the film thickness of the capacitive electrode 16 is 140 nm, the pixel electrode 15 is in the film thickness range of 126 nm to 154 nm, and the liquid crystal device 100 has a light wavelength range (530 nm to 590 nm) with high human visibility characteristics. ), And the alignment films 18 and 24 and the liquid crystal layer 50 have a peak in which the transmittance increases in the wavelength range (400 nm to 460 nm) of light that tends to cause deterioration. Therefore, it is possible to provide the liquid crystal device 100 which has excellent light resistance and a bright display.

  4) When one of the pixel electrode 15 and the capacitor electrode 16 is made thinner than the film thickness (140 nm) of the first embodiment and the other is made thicker than the film thickness (140 nm) of the first embodiment, the effect of reducing the film thickness and the film The effect of increasing the thickness is offset, and the spectral characteristics substantially equivalent to those of the first embodiment are obtained. Specifically, when the thickness of the pixel electrode 15 is 140 nm to 154 nm and the thickness of the capacitor electrode 16 is 126 nm to 140 nm, or the thickness of the pixel electrode 15 is 126 nm to 140 nm and the thickness of the capacitor electrode 16 is 140 nm to 154 nm. In any case, the liquid crystal device 100 has substantially the same spectral characteristics as the first embodiment. Therefore, even under these conditions, it is possible to provide the liquid crystal device 100 which is excellent in light resistance and has a particularly bright display.

5) The dielectric layer 14 is a multilayer film in which first dielectric films (hafnium oxide) and second dielectric films (aluminum oxide) are alternately stacked. By configuring the dielectric layer 14 with different dielectric films, the defect density of the dielectric layer 14 can be reduced and the dielectric layer 14 can be made thinner.
Furthermore, hafnium oxide, which is a constituent material of the first dielectric film, has a feature that the dielectric constant is large. Aluminum oxide, which is a constituent material of the second dielectric film, has a feature that leakage current is small. When the dielectric layer 14 has a structure in which hafnium oxide and aluminum oxide are stacked, a capacitor element (storage capacitor 17) having a large capacitance density, low leakage current, and excellent withstand voltage can be formed. .
Furthermore, the film thickness of the dielectric layer 14 is as extremely thin as 20 nm to 40 nm. By making the dielectric layer 14 very thin, it has high transparency to visible light. That is, the dielectric layer 14 has a wavelength range (400 nm to 460 nm) that tends to cause deterioration of the alignment films 18 and 24 and the liquid crystal layer 50, and light in a wavelength range (530 nm to 590 nm) where the sensitivity is high in human visibility characteristics. It has a high transmittance with respect to light.

(Embodiment 2)
"Electronics"
FIG. 14 is a schematic diagram illustrating a configuration of a projection display device as an electronic apparatus. As shown in FIG. 14, a projection display apparatus 1000 as an electronic apparatus according to the present embodiment includes a polarization illumination apparatus 1100 arranged along the system optical axis L, and two dichroic mirrors 1104 and 1105 as light separation elements. Three reflection mirrors 1106, 1107, 1108, five relay lenses 1201, 1202, 1203, 1204, 1205, three transmissive liquid crystal light valves 1210, 1220, 1230 as light modulation means, and a light combining element As a cross dichroic prism 1206 and a projection lens 1207.

  The polarized light illumination device 1100 is generally configured by a lamp unit 1101 as a light source composed of a white light source such as an ultra-high pressure mercury lamp or a halogen lamp, an integrator lens 1102, and a polarization conversion element 1103.

  The dichroic mirror 1104 reflects red light (R) and transmits green light (G) and blue light (B) among the polarized light beams emitted from the polarization illumination device 1100. Another dichroic mirror 1105 reflects the green light (G) transmitted through the dichroic mirror 1104 and transmits the blue light (B).

The red light (R) reflected by the dichroic mirror 1104 is reflected by the reflection mirror 1106 and then enters the liquid crystal light valve 1210 via the relay lens 1205.
Green light (G) reflected by the dichroic mirror 1105 enters the liquid crystal light valve 1220 via the relay lens 1204.
The blue light (B) transmitted through the dichroic mirror 1105 is incident on the liquid crystal light valve 1230 via a light guide system including three relay lenses 1201, 1202, 1203 and two reflection mirrors 1107, 1108.

  The liquid crystal light valves 1210, 1220, and 1230 are disposed to face the incident surfaces of the cross dichroic prism 1206 for each color light. The color light incident on the liquid crystal light valves 1210, 1220, and 1230 is modulated based on video information (video signal) and emitted toward the cross dichroic prism 1206. In this prism, four right-angle prisms are bonded together, and a dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light are formed in a cross shape on the inner surface thereof. The three color lights are synthesized by these dielectric multilayer films, and the light representing the color image is synthesized. The synthesized light is projected on the screen 1300 by the projection lens 1207 which is a projection optical system, and the image is enlarged and displayed.

  The liquid crystal light valve 1210 is obtained by applying the liquid crystal device 100 of the first embodiment described above. Light emitted from the polarization illumination device 1100 enters the counter substrate 20 (see FIG. 1) of the liquid crystal device 100 and is emitted from the element substrate 10 (see FIG. 1) toward the cross dichroic prism 1206. The liquid crystal device 100 is arranged with a gap between a pair of polarizing elements arranged in crossed Nicols on the incident side and the emission side of colored light. The same applies to the other liquid crystal light valves 1220 and 1230.

  According to such a projection type display apparatus 1000, light in a wavelength range (530 nm to 590 nm) in which sensitivity is high due to human visibility characteristics, and wavelengths that easily affect light degradation of the alignment films 18 and 24 and the liquid crystal layer 50. Since the liquid crystal device 100 having a high transmittance with respect to each light in the range (400 nm to 460 nm) is used as the liquid crystal light valves 1210, 1220, 1230, the bright display quality and the liquid crystal light valves 1210, 1220, 1230 are used. High reliability in which photodegradation is suppressed is realized.

The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the spirit or concept of the invention that can be read from the claims and the entire specification. Electronic equipment to which the liquid crystal device 100 is applied is also included in the technical scope of the present invention.
Various modifications other than the above embodiment are conceivable. Hereinafter, a modification will be described.

  (Modification 1) In Embodiment 1, the material constituting the pixel electrode 15 and the capacitor electrode 16 was ITO. The material constituting the pixel electrode 15 and the capacitor electrode 16 is not limited to ITO, and may be IZO (Indium Zinc Oxide).

  (Modification 2) In the first embodiment, light from the light source is incident from the counter substrate 20 toward the element substrate 10. The incident direction of light from the light source to the liquid crystal device 100 is not limited to the direction from the counter substrate 20 toward the element substrate 10, and may be the direction from the element substrate 10 toward the counter substrate 20.

  (Modification 3) The electronic apparatus to which the liquid crystal device 100 is applied is not limited to the projection display device 1000 of the second embodiment. In addition to the projection display device 1000, a projection type HUD (head-up display), a direct-view type HMD (head-mounted display), an electronic book, a personal computer, a digital still camera, a liquid crystal television, a viewfinder type, or a monitor direct-view type The liquid crystal device 100 according to the first embodiment and the liquid crystal devices according to the first and second modifications can be applied to electronic devices such as video recorders, car navigation systems, POS and other information terminal devices, and electronic notebooks. .

  CNT1, CNT2, CNT3, CNT4, CNT5, CNT7 ... contact hole, 3a ... scanning line, 3b ... capacitance line, 6a ... data line, 6b ... first relay electrode, 6c ... projection, 7a ... wiring, 7b ... second Relay electrode, 9 ... base insulating film, 10 ... element substrate, 10a ... element substrate body, 11a ... first insulating film, 11b ... second insulating film, 12 ... first interlayer insulating film, 13 ... second interlayer insulating film, DESCRIPTION OF SYMBOLS 14 ... Dielectric layer, 15 ... Pixel electrode, 15a ... Projection part, 16 ... Capacitance electrode, 16ch ... Opening part, 17 ... Storage capacity, 18, 24 ... Orientation film, 20 ... Counter substrate, 20a ... Counter substrate main body, 21 ... Light-shielding film, 22 ... Interlayer insulating film, 23 ... Counter electrode, 30 ... TFT, 30a ... Semiconductor layer, 30c ... Channel region, 30d ... Source / drain region on the pixel electrode side, 30e, 30f ... Junction region, 30g ... Gate current , 30 s... Data line side source / drain region, 31... Source electrode, 32... Drain electrode, 40... Sealing material, 50 ... liquid crystal layer, 100. DESCRIPTION OF SYMBOLS 103 ... Inspection circuit, 104 ... External connection terminal, 105 ... Wiring, 106 ... Vertical conduction part, 1000 ... Projection type display apparatus, 1100 ... Polarized illumination apparatus, 1101 ... Lamp unit, 1102 ... Integrator lens, 1103 ... Polarization conversion element 1104, 1105 ... Dichroic mirror, 1106, 1107, 1108 ... Reflection mirror, 1201, 1202, 1203, 1204, 1205 ... Relay lens, 1206 ... Cross dichroic prism, 1207 ... Projection lens, 1210, 1220, 1230 ... Liquid crystal light valve 1300 ... Scree .

Claims (8)

A substrate,
A storage capacitor comprising: a pixel electrode; a capacitor electrode disposed opposite to the pixel electrode between the substrate and the pixel electrode; and a dielectric layer sandwiched between the pixel electrode and the capacitor electrode; ,
With
An electro-optical device, wherein a spectral distribution of light transmitted through the substrate and the storage capacitor has peaks in a wavelength range of 530 nm to 590 nm and a wavelength range of 400 nm to 460 nm.   The electro-optical device according to claim 1, wherein the dielectric layer includes a first dielectric film and a second dielectric film.   The electro-optical device according to claim 2, wherein the first dielectric film is hafnium oxide and the second dielectric film is aluminum oxide.   4. The pixel electrode and the capacitor electrode are ITO films, and the film thickness of the pixel electrode and the film thickness of the capacitor electrode are in the range of 126 nm to 154 nm. The electro-optical device according to 1.   5. The electro-optical device according to claim 4, wherein the pixel electrode has a thickness in a range of 140 nm to 154 nm, and the capacitor electrode has a thickness in a range of 126 nm to 140 nm.   The electro-optical device according to claim 4, wherein the pixel electrode has a thickness in a range of 126 nm to 140 nm, and the capacitive electrode has a thickness in a range of 140 nm to 154 nm.   The dielectric layer is a multilayer film in which the first dielectric film and the second dielectric film are alternately stacked, and the thickness of the dielectric layer is in the range of 20 nm to 50 nm. The electro-optical device according to claim 2.   An electronic apparatus comprising the electro-optical device according to claim 1.

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