JP3832110B2 - Liquid crystal device, manufacturing method thereof, and electronic apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a liquid crystal device that displays images such as letters, numbers, and patterns by controlling the orientation of liquid crystal sealed between a pair of substrates, and a method for manufacturing the same. The present invention also relates to an electronic device configured using the liquid crystal device.
[0002]
[Prior art]
In recent years, liquid crystal devices have been widely used in image display units of electronic devices such as portable computers, mobile phones, video cameras, and the like. In general, this liquid crystal device displays images such as letters, numbers, and patterns by controlling the orientation of liquid crystal sealed between a pair of substrates.
[0003]
Such liquid crystal devices include a simple matrix type liquid crystal device that does not use active elements and an active matrix type liquid crystal device that uses active elements. As such an active matrix liquid crystal device, a liquid crystal device having a structure using a TFT (Thin Film Transistor) element, a TFD (Thin Film Diode) element, or the like as an active element is known.
[0004]
When the above-mentioned simple matrix type and active matrix type liquid crystal devices are classified according to the illumination system, a reflector is attached to the outer surface of the liquid crystal panel, and sunlight or other external light is reflected by the reflector to illuminate the reflected light. It is known that there are a reflection type liquid crystal device of a type used as light and a transmission type of liquid crystal device of a type in which an illumination device such as a backlight is attached to a liquid crystal panel and light from the illumination device is used as illumination light. .
[0005]
Considering a reflective liquid crystal device now, in many cases, a reflector is attached to one outer surface of a pair of substrates constituting the liquid crystal device, and external light incident from the outside of the other substrate is reflected on the reflector. And the reflected light is supplied to the liquid crystal. In addition, recently, instead of attaching a reflector to the outer surface of one substrate, an electrode formed on the inner surface of the substrate is formed of a light reflecting material such as aluminum, and the electrode is used as a reflector. A liquid crystal device having a function is also known.
[0006]
As described above, with respect to the liquid crystal device having a structure in which the electrode provided on one substrate itself is used as a reflection plate, it is not necessary to use a dedicated reflection plate, so that the component cost is reduced and the manufacturing process is simplified. Therefore, the manufacturing cost is also reduced.
[0007]
[Problems to be solved by the invention]
However, in the conventional liquid crystal device in which the electrode itself is used as a reflecting plate, the surface of the electrode is often a smooth surface, and as a result, the traveling direction of the reflected light from the electrode is limited to a narrow angle. Therefore, it has been difficult to obtain a bright display at a wide viewing angle.
[0008]
Japanese Laid-Open Patent Publication No. 58-125084 discloses a liquid crystal device having a structure in which a metal film deposited on the surface of a resin layer having smooth irregularities is used as both an electrode and a reflective film. In this liquid crystal device, it is considered that when the metal film is used as a reflection film, reflected light in a scattered state can be formed by the above-described unevenness, and thus bright reflected light with high contrast can be obtained within a wide viewing angle range. Yes.
[0009]
Kashina grounds in this conventional liquid crystal device, and unevenness of the resin layer is formed by using a photoetching method, therefore, the surface of the irregularities is rather smooth, further patterns of irregularities is also a fairly regular array It has become. As a result, the metal film has a limit in obtaining a bright display within a wide viewing angle range.
[0010]
The present invention has been made in view of the above-mentioned problems, and uses a structure in which an electrode formed on the inner surface of a substrate is used as a reflection plate to display a bright display within a very wide viewing angle range. It is an object to provide a liquid crystal device and an electronic device that can be obtained. Moreover, it aims at providing the manufacturing method which can manufacture such a liquid crystal device reliably.
[0011]
[Means for Solving the Problems]
(1) In order to achieve the above object, a liquid crystal device according to the present invention is a liquid crystal device in which liquid crystal is sandwiched between a pair of substrates, and an electrode formed of a light reflecting material is provided on at least one of the substrates. A plurality of granular members dispersed and irregularly arranged on the substrate by electrostatic spraying are positioned between the electrode and the substrate on which the electrode is provided; It is formed so that a member may be wrapped, and the unevenness | corrugation by the said granular member is formed in the surface of the said electrode, It is characterized by the above-mentioned.
[0012]
This liquid crystal device can be an active matrix liquid crystal device using an active element such as a TFT element or a TFD element, or a simple matrix liquid crystal device using no active element. Moreover, the electrode which makes an unevenness | corrugation on the surface by a granular member may be an electrode formed in either of a pair of board | substrates. For example, in the case of an active matrix liquid crystal device, a granular member can be provided for an electrode formed on either the element side substrate constituting the liquid crystal device or the counter substrate facing the element side substrate.
[0013]
In the above configuration, for example, aluminum can be used as the “light reflecting material”. As the “granular member”, a resin ball having elasticity can be used. As this granular member, one having a particle size such that the height from the uneven valleys to the peaks formed on the electrode surface is about 1 μm is used.
[0014]
According to the liquid crystal device having the above configuration, the surface of the electrode functioning as a light reflecting member is provided with unevenness, so that the light reflected by this electrode is scattered, and as a result, an image displayed using this reflected light is Brightens within a wide viewing angle range.
[0015]
In particular, the irregularities formed on the electrode surface are caused by granular members dispersed on the surface of the substrate, and these granular members are irregularly distributed in the substrate plane. For this reason, the irregularities formed on the electrode surface are irregularly arranged in a plan view, so that the light reflected by the electrode spreads uniformly over a wide angular range. As a result, a very bright display can be obtained within a very wide viewing angle range.
[0016]
(2) With respect to the liquid crystal device having the above configuration, the pair of substrates can be an active matrix liquid crystal device including an element-side substrate including an active element and a counter substrate facing the element-side substrate. The granular member can be dispersed on the surface of the element side substrate. According to this liquid crystal device, a very bright display can be obtained within a very wide viewing angle range with respect to the active matrix type liquid crystal device.
[0017]
(3) In the liquid crystal device having the above configuration, the granular member can be dispersed on the substrate by electrostatic scattering. Here, “electrostatic spraying” is to disperse the granular member in a state where a charge is applied to the granular member. Since the granular members dispersed by electrostatic spraying are dispersed while repelling each other electrostatically, a mass due to a plurality of granular members is not generated. It is possible to prevent the formation of excessive unevenness.
[0018]
(4) In the liquid crystal device having the above configuration, the granular member can be formed of a thermosetting resin. The thermosetting resin referred to here is a resin that melts temporarily when subjected to a temperature above a predetermined level, solidifies after that, and does not melt even when subjected to a temperature above the predetermined level after solidification. That is.
[0019]
As the granular member, in addition to the thermosetting resin as described above, a resin having a property of being melted by heat can be widely used. However, it is considered more desirable to use the thermosetting resin as described above. The reason is that even when various heat treatments are performed on the substrate after the granular member is dispersed on the substrate, it is possible to prevent the granular member from being affected by the heat treatment, for example, melting and deformation. is there.
[0020]
(5) Next, a method for manufacturing a liquid crystal device according to the present invention is the method for manufacturing a liquid crystal device for manufacturing a liquid crystal device having a liquid crystal sandwiched between a pair of substrates. A granular member dispersing step for irregularly dispersing the granular member on the surface of the substrate by electrostatic spraying ; an electrode by a light reflecting material on the surface of the substrate in which the granular member is dispersed and irregularly arranged; and the granular member And an electrode forming step of forming an envelope.
[0021]
According to this method for manufacturing a liquid crystal device, it is possible to form irregularities on the surface of the electrode functioning as a reflecting member inside the liquid crystal device, so that light reflected by this electrode can be displayed when displaying in the manufactured liquid crystal device. As a result, bright display can be performed within a wide viewing angle range.
[0022]
In particular, the irregularities formed on the electrode surface are caused by granular members dispersed on the surface of the substrate, and these granular members are irregularly distributed in the substrate plane, and thus formed on the electrode surface. The irregularities are irregularly arranged in plan view. For this reason, the light reflected by the electrode spreads uniformly within a wide angle range, and therefore, a very bright display can be obtained within a very wide viewing angle range.
[0023]
(6) The manufacturing method of the said structure can include the active element formation process of forming the active element containing an element side electrode in either one of said pair of board | substrates. That is, the present invention can be applied to a manufacturing method for manufacturing an active matrix liquid crystal device. In this case, the electrode forming step is a step of forming a pixel electrode so as to be connected to the element side electrode, and the granular member dispersing step is performed after the active element forming step. Before the electrode forming step.
[0024]
According to this configuration, since the granular member is dispersed on the surface of the substrate after the active element is formed on the substrate, the surface of the substrate is a smooth flat surface when forming the active element, and thus the characteristics of the active element It is possible to reliably prevent defects and variations from occurring.
[0025]
(7) With regard to the manufacturing method having the above configuration, a granular member heating step can be provided between the granular member dispersing step and the electrode forming step, and the granular member dispersed on the substrate in the granular member heating step. The surface portion of can be temporarily melted. According to this configuration, since the granular member can be firmly fixed to the substrate surface, the display characteristics of the liquid crystal device can be stabilized.
[0026]
(8) In the case where the granular member is heated as described above, as a specific method thereof, a method of heating the heated plate, that is, a so-called hot plate, close to the granular member can be employed.
[0027]
As a method for heating the granular member, in addition to the method using the heated plate as described above, a method of blowing hot air and various other methods can be considered. However, in the method using hot air, there may be a disadvantage that the granular member dispersed on the substrate is blown off from the substrate. On the other hand, according to the method using a hot plate, such scattering of the granular member can be prevented.
[0028]
(9) In the manufacturing method of the said structure, a granular member dispersion | distribution process can be implemented including the process which disperse | distributes the said granular member on a board | substrate by electrostatic spraying. Since the granular members dispersed by electrostatic spraying are dispersed while repelling each other electrostatically, a mass due to a plurality of granular members is not generated. (10) In the manufacturing method having the above-described configuration, the granular member can be formed of a thermosetting resin. According to this configuration, even when various heat treatments are performed on the substrate after the granular member is dispersed on the substrate, the granular member can be prevented from being affected by the heat treatment, for example, melting and deformation. .
[0029]
(11) Next, an electronic apparatus according to the present invention includes the liquid crystal device having the above-described configuration and a housing that houses the liquid crystal device. Specific examples of such an electronic device include a portable computer, a mobile phone, and a video camera. In many cases, a liquid crystal device is applied to the image display unit.
[0030]
According to this electronic apparatus, in the liquid crystal device included therein, the irregularities formed on the electrode surface are brought about by the granular members dispersed on the surface of the substrate. Therefore, the granular members are irregularly formed in the substrate plane. Thus, the unevenness formed on the electrode surface is irregularly arranged in plan view. For this reason, the light reflected by the electrode spreads evenly within a wide angle range, and thus a very bright display can be obtained within a very wide viewing angle range.
[0031]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
FIG. 1 is a plan view of a liquid crystal device according to an embodiment of the present invention, partially broken away. The liquid crystal device 1 shown here has a pair of translucent substrates 3 a and 3 b joined to each other by a sealing material 2. These translucent substrates are made of glass, plastic, or the like, for example. A gap, a so-called cell gap, is formed between these translucent substrates, and the liquid crystal is sealed in the portion of the cell gap surrounded by the sealing material 2.
[0032]
The translucent substrate 3a on the back side in the figure is an element-side substrate, and on its inner surface, a plurality of linear wirings arranged in parallel with each other, that is, striped wirings 4 are formed. 4, a plurality of pixel electrodes 6 are formed in a dot matrix, and each pixel electrode 6 and each wiring 4 are connected via a TFD element 7 as an active element. A polarizing plate 12 is attached to the outer surface of the element side substrate 3a. In the present embodiment, each pixel electrode 6 is formed of a light reflecting material such as aluminum.
[0033]
On the other hand, the translucent substrate 3b on the near side in FIG. 1 is a counter substrate, and a striped counter electrode 8 is formed on the inner surface thereof. A plurality of pixels arranged in a dot matrix are formed in a portion where the counter electrode 8 and the pixel electrode 6 on the element side substrate 3a are opposed to each other. A color filter is further formed on the inner surface of the counter substrate 3b as necessary. A polarizing plate 12 is attached to the outer surface of the counter substrate 3b.
[0034]
In the element side substrate 3a, a large number of wirings 4 are actually formed on the substrate 3a with extremely narrow spacing. In FIG. 1, the spacing dimensions of the wirings 4 are shown for easy understanding of the structure. An enlarged schematic view is shown, and some of the wires 4 are shown, and the other parts are omitted. In addition, the pixel electrodes 6 are actually very small in area and are arranged in a dot matrix at fine intervals, but in FIG. 1, each pixel electrode 6 is enlarged and schematically shown for easy understanding of the structure. And the space between them is enlarged.
[0035]
In the counter substrate 3b, a large number of counter electrodes 8 are actually formed at extremely narrow intervals so as to oppose the pixel electrodes 6 on the element side substrate 3a. However, in FIG. For the sake of illustration, the interval between the opposing electrodes 8 is schematically shown in an enlarged manner, and a part of the opposing electrodes 8 is omitted.
[0036]
An alignment film is further formed of polyimide or the like on the inner surface of the element side substrate 3a on which the pixel electrodes 6 and the like are formed, and the alignment film is subjected to uniaxial alignment processing, for example, rubbing processing. In addition, an alignment film is formed of polyimide or the like on the inner surface of the counter substrate 3b on which the counter electrode 8 is formed, and the alignment film is also subjected to uniaxial alignment processing, for example, rubbing processing.
[0037]
The liquid crystal device 1 according to the present embodiment is a COG (Chip On Glass) type liquid crystal device. Therefore, the liquid crystal driving IC 9a is directly mounted on the surface of the element side substrate 3a, and the liquid crystal device is also formed on the surface of the counter substrate 3b. The driving IC 9b is directly mounted. The wiring 4 formed on the element side substrate 3a is connected to the output terminal of the liquid crystal driving IC 9a, while the counter electrode 8 formed on the counter substrate 3b is connected to the output terminal of the liquid crystal driving IC 9b. . Reference numeral 11 denotes an external connection terminal for connecting the liquid crystal driving ICs 9a and 9b to an external circuit.
[0038]
When the liquid crystal driving ICs 9a and 9b are operated, predetermined ON and OFF voltages are applied between the pixel electrode 6 corresponding to the selected pixel and the counter electrode 8, and the liquid crystal alignment state is controlled by this voltage control. To control. Then, by modulating the light based on this orientation control, images such as letters, numbers, and patterns are displayed outside. At this time, the light supplied to the liquid crystal is external light, for example, sunlight, which is taken into the liquid crystal device from the counter substrate 3b side and then reflected by the pixel electrode 6 formed of an aluminum alloy. Note that the wiring 4 may be used as a data line or a scanning line.
[0039]
FIG. 9 shows an enlarged view of the vicinity of one pixel region on the inner surface of the element-side substrate 3a. FIG. 10 shows a cross-sectional structure according to the line AA in FIG. In these drawings, the wiring 4 includes a first layer 4a formed of a conductive material such as Ta (tantalum), and a second layer 4b formed of an anodic oxide film laminated on the first layer 4a. The third layer 4c is formed of a conductive material such as Cr (chromium) on the second layer 4b.
[0040]
The TFD element 7 is formed as an element having a so-called back-to-back structure by connecting a pair of MIM elements 14a and 14b in series in an electrically reverse direction. With this back-to-back structure, stable switching characteristics can be obtained as compared with the case of using one MIM element. Of course, a non-linear element can also be configured using one MIM element.
[0041]
Each of the MIM elements 14 a and 14 b includes a first electrode 16 formed of Ta or the like simultaneously with the first layer 4 a of the wiring 4, an anodic oxide film 17 formed on the first electrode 16, and the wiring 4. The second layer 18 is formed of Cr or the like simultaneously with the third layer 4c. In the figure, the second electrode closer to the wiring 4 is indicated by 18a, and the second electrode farther from the wiring 4, that is, closer to the pixel electrode 6, is indicated by 18b. The pixel electrode 6 is formed so as to overlap the tip portion of the second electrode 18b. The pixel electrode 6 is formed in a substantially rectangular shape as shown in FIG. 9, and the tip portion of the second electrode 18 b connected to the pixel electrode 6 is formed in a rectangular shape slightly larger than the pixel electrode 6.
[0042]
As shown in FIG. 9, a plurality of granular members 10 are provided in an irregular arrangement state on the element side substrate 3a. Looking at the portion where the pixel electrode 6 is formed, as shown in FIG. 10, the granular member 10 is located between the pixel electrode 6 and the second electrode 18b of the MIM element 14b. Since these granular members 10 are present, irregularities are formed on the surface of the pixel electrode 6.
[0043]
The plurality of granular members 10 are dispersed on the substrate 3a by, for example, an electrostatic spraying method. Therefore, the planar arrangement of the granular members 10 is irregular as shown in FIG. In FIG. 9, the density of the granular members 10 is shown to be relatively small for easy understanding of the structure. However, in practice, it is desirable to disperse the granular members 10 at a higher density.
[0044]
Here, electrostatic spraying is to disperse the granular member in a state where a charge is applied to the granular member, and the plurality of dispersed granular members are separated from each other, so that no lump is formed. Therefore, excessive unevenness is not formed on the surface of the pixel electrode 6.
[0045]
In the present embodiment, as described above, the surface of the pixel electrode 6 is uneven due to the granular member 10, so that the light reflected by the pixel electrode 6 is scattered over a wide angular range. In particular, since the planar arrangement of the granular members 10 is irregular, the light diffusion angle becomes very wide, and thus the display of the liquid crystal device becomes bright within a very wide viewing angle range.
[0046]
Hereinafter, a manufacturing method for manufacturing the liquid crystal device 1 having the above configuration will be described with reference to FIGS. In step (a) of FIG. 2, first, a glass substrate base material 3a ′ is prepared. The glass substrate base material 3a ′ is formed of a large-area glass substrate having an area enough to form a plurality of element-side substrates 3a each having a size corresponding to that of the liquid crystal device 1 shown in FIG. A tantalum oxide such as Ta ₂ O ₅ is formed on the surface of the element side substrate base material 3a ′. Is formed in a uniform thickness to form the underlayer 19. The underlayer 19 is formed for the purpose of improving the adhesion of the film formed on the substrate base material 3a ′ thereafter to the substrate base material 3a ′.
[0047]
Next, in step (b), tantalum (Ta) is formed into a uniform thickness by sputtering or the like, and further subjected to photolithography or the like, so that the first layer 4a of the wiring 4 and the MIM element 14a and The first electrode 16 of 14b is formed. A plan view of this state is as shown in FIG. In this state, the first wiring layer 4a and the first electrode 16 for the MIM element are connected together.
[0048]
Next, in step (c), anodization is performed using the first layer 4a of the wiring as the anode terminal, and the anode acting as an insulating film on the first layer 4a and the first electrode 16 for the MIM element. An oxide film is formed to a uniform thickness. Thereby, the second layer 4b of the wiring 4 and the insulating layer 17 of the MIM elements 14a and 14b are formed. A plan view of this state is as shown in FIG.
[0049]
Next, in the step (d), an element portion photoetching (abbreviated as PE in the drawing) step is executed. This step is a step for partially removing the portion B connecting the first layer 4a and the second layer 4b of the wiring 4 with the first electrode 16 and the insulating film 17 of the MIM element by etching in FIG. is there. By this step, the first electrode 16 and the insulating layer 17 of the MIM elements 14a and 14b are divided into island shapes from the first layer 4a and the second layer 4b of the wiring 4, and the state shown in FIG. 6 is obtained.
[0050]
Next, in the step (e) of FIG. 3, a chromium film is formed with a uniform thickness by sputtering or the like, and further, a photolithography process is performed, so that the third layer 4c of the wiring 4 and the MIM element 14a and The second electrodes 18a and 18b of 14b are formed. A plan view of this state is as shown in FIG. At this time, the tip portion of the second electrode 18b formed on the side far from the wiring 4 is formed in substantially the same shape as one pixel.
[0051]
Next, in the step (f), a plurality of granular members, for example, balls having elasticity formed of a thermosetting resin are dispersed on the substrate base material 3a ′ using an electrostatic spraying method. According to the electrostatic spraying method, since the electric charges having the same potential are applied to the individual granular members to be dispersed, it is possible to prevent the granular members from being combined into a lump. Further, as shown in FIG. 8, the dispersed granular members 10 are arranged in an irregular state when seen in a plan view. 3 and 8, the distribution density of the plurality of granular members 10 is shown coarser than the actual case in order to show the structure in an easy-to-understand manner.
[0052]
Thereafter, in step (g), the granular member 10 is heated by placing the substrate base material 3a ′ on a hot plate heated to a predetermined temperature or bringing it close to the hot plate. In the present embodiment, since the granular member 10 is formed of a thermosetting resin, the granular member 10 is heated to a predetermined temperature to be temporarily melted and then solidified, and after the solidification, the predetermined temperature is reached. Even if heated to the above, it is kept in a state where it does not melt. By this heating step, each granular member 10 is firmly fixed on the substrate base material 3a ′ or on various elements formed on the base material 3a ′.
[0053]
Thereafter, in the step (h), a process for forming the pixel electrode 6 is executed. Specifically, an aluminum alloy that is a material of the pixel electrode 6 is formed into a uniform thickness by sputtering or the like, and further, a photolithography process including an etching process is performed, which is indicated by reference numeral 6 in FIG. A pixel electrode having a predetermined shape corresponding to the size of one pixel is formed on the tip portion of the second electrode 18b, that is, on the chromium pattern. At this time, since there are a plurality of irregularly arranged granular members 10 between the pixel electrode 6 and the chromium pattern of the second electrode 18b, the surface of the pixel electrode 6 corresponds to these granular members 10. Irregular pattern is formed. When performing display in a liquid crystal device, the light reflected by the pixel electrode 6 is scattered at a wide angle by the function of the irregular uneven pattern, and as a result, a bright display can be performed within a wide viewing angle range. .
[0054]
Through the above operations, the element side substrate base material 3a ′ including a plurality of element side substrates 3a shown in FIG. 1 is completed. On the other hand, a counter substrate base material including a plurality of counter substrates 3b is manufactured by a separate operation. A sealing material 2 is formed by screen printing or the like on the surface of any one of the element-side substrate base material 3a ′ and the counter substrate base material formed in this manner so as to correspond to each liquid crystal device portion.
[0055]
Thereafter, the element side substrate base material 3a ′ and the counter substrate base material are bonded to each other with the sealing material 2 interposed therebetween to produce a large-area panel structure, and further inside each liquid crystal device portion of the panel structure. Each liquid crystal panel is cut out by enclosing the liquid crystal, further forming a cutting groove, so-called scribe groove, at a predetermined position of each substrate base material, and further cutting each substrate base material according to the cutting groove, so-called breaking. . By attaching the polarizing plate 12 and the liquid crystal driving ICs 9a and 9b shown in FIG. 1 to the individual liquid crystal panels thus cut out, the liquid crystal device 1 shown in FIG. 1 is completed.
[0056]
(Second Embodiment)
FIG. 11 shows a portable computer which is an embodiment of an electronic apparatus according to the present invention configured using the liquid crystal device 1 shown in FIG. The portable computer 31 includes a keyboard 33 having a plurality of keys 32, a cover 34 that opens and closes as shown by an arrow D with respect to the keyboard 33, and a cover 34 embedded in the cover 34. And a liquid crystal device 30. The liquid crystal device 30 is manufactured by mounting auxiliary equipment such as a control circuit on the liquid crystal device 1 of FIG.
[0057]
Inside the keyboard unit 33 is stored a control unit including a CPU (Central Processing Unit) for executing various calculations for performing functions as a portable computer. The control unit executes arithmetic processing for displaying a predetermined video on the liquid crystal device 30.
[0058]
In the portable computer according to the present embodiment, as shown in FIG. 10, the liquid crystal device used in the portable computer is uneven due to the granular member 10 on the surface of the pixel electrode 6, and is reflected by the pixel electrode 6. Light is dispersed over a wide angular range. In particular, since the planar arrangement of the granular members 10 is irregular, the light diffusion angle becomes very wide, and thus the display of the liquid crystal device becomes bright within a very wide viewing angle range.
[0059]
(Other embodiments)
The liquid crystal device shown in FIG. 1 is a COG type liquid crystal device, but the present invention can be applied to any liquid crystal device having any other structure. For example, a so-called TAB method having a structure using TCP (Tape Carrier Package) formed by bonding an IC chip on an FPC (Flexible Printed Circuit) using TAB (Tape Automated Bonding) technology. The present invention can be applied to a liquid crystal device. The present invention can also be applied to a so-called COB (Chip On Board) type liquid crystal device having a structure in which an IC chip is mounted on a substrate other than glass such as an epoxy substrate.
[0060]
The above embodiment exemplifies the case where a back-to-back TFD element having a structure in which a pair of MIM elements are connected in series with opposite polarity is used as a nonlinear element, but a TFD element having a structure using one MIM element. Alternatively, a TFT element can be used instead of the TFD element.
[0061]
FIG. 12 is a partial plan view of a liquid crystal device using a TFT element, and FIG. 13 is a partial cross-sectional view taken along line BB in FIG.
[0062]
As shown in FIG. 12 and FIG. 13, the TFT element portion 104 extends in a region shown by hatching in FIG. 5, the source 1041 is conductively connected to the data line 103 through the opening 1041a, and the gate 1042 is scanned. The line 101 is formed so as to face the line 101 through a thin insulating film (not shown). The drain 1043 is conductively connected to the pixel electrode 106 through the opening 1043a. The lower electrode 1040 extending from these structures overlaps with the capacitor line 102 in a planar manner via the insulating layer, thereby forming the storage capacitor 105. The storage capacitor 105 is for holding the potential of the pixel electrode 106 for a long time against charge leakage as is well known.
[0063]
In a liquid crystal device using this TFT element, an insulating layer 105 is formed on the data line 103. After forming the insulating layer 105, as in the first embodiment, for example, the granular member 10 such as a ball having elasticity formed of a thermosetting resin is dispersed on the substrate 100 by using an electrostatic spraying method. To do. At this time, there is a possibility that the granular member 10 is disposed in a region to be a through hole 1043a that connects the pixel electrode 106 and the drain 1043 later. The granular member in the region is formed in the step of forming the through hole. Since the insulating layer 105 and the underlying film are removed together, there is no problem. In FIGS. 12 and 13, the size and distribution density of the plurality of granular members 10 are larger and coarser than the actual case in order to easily understand the structure.
[0064]
Next, the granular member 10 is heated by placing the substrate 100 on a hot plate heated to a predetermined temperature or bringing it close to the hot plate, and the granular member 10 is temporarily melted and then solidified.
[0065]
Next, a through hole 1043a reaching the drain 1043 is formed, and then a pixel electrode 106 is formed on the insulating layer on which irregularities are formed by the granular member 10, for example, by an aluminum alloy.
[0066]
After this, the substrate is bonded to a counter substrate (not shown) through a known alignment film formation and rubbing treatment process, and a so-called multiple substrate is taken. Enclose the liquid crystal. Then, a necessary control circuit, wiring, and the like are mounted to configure a liquid crystal device.
[0067]
Since the liquid crystal device using the TFT element configured as described above has irregularities on the surface of the pixel electrode 106 due to the granular member 10, the light reflected by the pixel electrode 106 is scattered over a wide angle range. In particular, since the planar arrangement of the granular members 10 is irregular, the light diffusion angle becomes very wide, and thus the display of the liquid crystal device becomes bright within a very wide viewing angle range.
[0068]
In each of the above embodiments, a so-called active matrix liquid crystal device using active elements such as TFD and TFT elements has been described. However, the present invention is applicable to a simple matrix liquid crystal device that does not use active elements. You can also.
[0069]
Further, although FIG. 11 illustrates a portable computer as an electronic device, the liquid crystal device according to the present invention can be applied to any other electronic device such as a mobile phone.
[0070]
【The invention's effect】
According to the liquid crystal device, the manufacturing method thereof, and the electronic apparatus according to the present invention, since the surface of the electrode functioning as the reflecting member is provided with unevenness, the light reflected by the electrode is scattered, and as a result, the reflected light is used. The displayed image becomes bright within a wide viewing angle range. In particular, the irregularities formed on the electrode surface are caused by granular members dispersed on the surface of the substrate, and these granular members are irregularly dispersed in the substrate plane. For this reason, the unevenness formed on the electrode surface is irregularly arranged in a plan view, and therefore, the light reflected by the electrode spreads evenly within a wide angle range. As a result, a very bright display can be obtained within a very wide viewing angle range.
[Brief description of the drawings]
FIG. 1 is a plan view illustrating a liquid crystal device according to an embodiment of the present invention, partially broken away.
FIG. 2 is a process chart schematically showing a method for manufacturing a liquid crystal device according to the present invention.
FIG. 3 is a process drawing subsequent to FIG. 2;
FIG. 4 is a plan view illustrating an example of a manufacturing process of a liquid crystal device.
FIG. 5 is a plan view illustrating another example of the manufacturing process of the liquid crystal device.
FIG. 6 is a plan view showing still another example of the manufacturing process of the liquid crystal device.
FIG. 7 is a plan view showing still another example of the manufacturing process of the liquid crystal device.
FIG. 8 is a plan view showing still another example of the manufacturing process of the liquid crystal device.
FIG. 9 is a plan view showing still another example of the manufacturing process of the liquid crystal device, and shows a state in which pixel electrodes are formed.
10 is a cross-sectional view showing a cross-sectional structure according to the AA line of FIG. 9;
FIG. 11 is a perspective view showing an embodiment of an electronic apparatus according to the invention.
FIG. 12 is a partial plan view showing an embodiment of another liquid crystal device according to the present invention.
FIG. 13 is a partial cross section showing an embodiment of another liquid crystal device according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Liquid crystal device 2 Sealing material 3a Element side board | substrate 3a 'Element side board | substrate base material 3b Counter substrate 4 Wiring 4a 1st layer 4b 2nd layer 4c 3rd layer 6 Pixel electrode 7 TFD element 8 Counter electrode 10 Granular member 14a, 14b MIM Element 16 First electrode 17 Insulating layer 18a Second electrode 18b Second electrode 19 Underlayer 100 Element side substrate 101 Scan line 102 Capacitance line 103 Data line 104 TFT element part 1043 Drain 1043a Through hole 105 Insulating layer 106 Pixel electrode

Claims (8)

In a liquid crystal device in which a liquid crystal is sandwiched between a pair of substrates,
An electrode formed of a light reflecting material is provided on at least one of the substrates,
Between the electrode and the substrate provided with the electrode, a plurality of granular members dispersed and irregularly arranged on the substrate by electrostatic scattering are located,
The electrode is formed so as to enclose the granular member, and the surface of the electrode is provided with irregularities due to the granular member. In claim 1,
The pair of substrates is constituted by an element side substrate including an active element and a counter substrate facing the element side substrate,
The liquid crystal device, wherein the plurality of granular members are dispersed on a surface of the element side substrate. In claim 1 or claim 2 ,
The liquid crystal device, wherein the granular member is formed of a thermosetting resin. In a method of manufacturing a liquid crystal device for manufacturing a liquid crystal device having a liquid crystal sandwiched between a pair of substrates,
A granular member dispersing step for irregularly dispersing the granular member on one surface of the pair of substrates by electrostatic spraying ;
A method of manufacturing a liquid crystal device, comprising: forming an electrode on a surface of the substrate in which the granular members are dispersed and arranged irregularly by a light reflecting material so as to enclose the granular members. . In claim 4 ,
An active element forming step of forming an active element including an element side electrode on either one of the pair of substrates;
The electrode forming step is a step of forming a pixel electrode so as to be connected to the element side electrode,
The method for manufacturing a liquid crystal device, wherein the granular member dispersion step is performed after the active element formation step and before the electrode formation step. In claim 4 or claim 5 ,
The granular member is formed of a thermosetting resin,
A granular member heating step is provided between the granular member dispersing step and the electrode forming step, and in the granular member heating step, the surface portion of the granular member dispersed on the substrate is temporarily melted and fixed to the substrate. A method of manufacturing a liquid crystal device. 7. The method of manufacturing a liquid crystal device according to claim 6 , wherein the granular member heating step is performed by bringing a heated plate close to the granular member. An electronic apparatus claim 1 and the liquid crystal device according to any one of claims 3, characterized in that it has a housing accommodating the liquid crystal device.

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