JP2005062447A - Liquid crystal device, method for manufacturing liquid crystal device, and projection display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal device in which no discharge trace of a liquid crystal material is produced, no heat is produced even when exposed to intense incident light and no active element is adversely affected by light reflection or by return light and of which the display quality is stable, an easy method for manufacturing the liquid crystal device and a projection display device provided with the liquid crystal device. <P>SOLUTION: The liquid crystal device has a liquid crystal material interposed between a pair of substrates and a pixel region provided with a plurality of active elements formed in a matrix on one substrate out of the pair of substrates, and is characterized in that the liquid crystal device is provided with a partition wall disposed between the pair of substrates and formed on a boundary region of the pixel region, a light shielding film composed of a metal film and disposed between the partition wall and the other substrate out of the pair of substrates on a position corresponding to the partition wall, and a liquid crystal material layer disposed in a recessed part formed of the partition wall. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a liquid crystal device, a method for manufacturing the liquid crystal device, and a projection display device.

As a liquid crystal device used for a projection display device such as a liquid crystal projector, a liquid crystal device described in Patent Document 1 below is known.
Patent Document 1 has a TFT array substrate in which a plurality of pixel electrodes and pixel switching thin film transistors are formed on a transparent substrate, a counter electrode facing the pixel electrode, and a counter substrate in which a light shielding film is formed between the pixel regions, A liquid crystal device is disclosed in which the light-shielding film has a two-layer structure of a light high-reflection layer and a low-reflection layer.

With this liquid crystal device, strong light from the light source is reflected by the light-shielding film of the high reflection layer disposed on the counter substrate, and heat generation is small, and return light from the TFT array substrate side is not reflected by the low reflection layer, but stray light It is described that generation | occurrence | production of can be prevented.
Japanese Patent Laid-Open No. 2003-131590

  However, in the liquid crystal device described in Patent Document 1, a counter substrate is bonded to a TFT array substrate, and a liquid crystal material is sealed to form a liquid crystal device. However, after a pair of substrates are bonded together, a seal that bonds the substrates together In a method of injecting a liquid crystal material from an injection port provided in a part of the material, there is a possibility that an arc-shaped ejection trace in which the liquid crystal material spreads from the injection port to the inside of the substrate may remain. In addition, before the substrates are pasted together, the liquid crystal material is ejected inside the sealing material for pasting the substrates. In this case, a discharge mark that the liquid crystal material spreads in an arc shape remains. Further, in the case of injecting liquid crystal material with a droplet discharge device such as an ink jet device, the liquid crystal material is discharged while moving the ink jet head in a line shape. The liquid crystal material layer is formed with a uniform height on the surface, but even in this case, the line-shaped ejection trace remains. As a result, the display quality of the liquid crystal device is deteriorated due to the ejection trace. In particular, in a projection type display device that is displayed in an enlarged manner, this ejection trace is a major problem in reducing the display image quality.

  On the other hand, the liquid crystal device described in Patent Document 1 prevents reflection of return light in a region where a light-shielding film is formed, but prevents other incident light such as bent incident light or light reflected by a counter substrate. And the light will be incident on the active device. The active element is also shielded by the data line, but part of this light will increase the leakage current of the channel and drain region of the active element, causing the display image quality to deteriorate. obtain.

  The present invention has been made in view of the above circumstances, and by a very simple method, there is no discharge trace of the liquid crystal material, no heat is generated with respect to strong incident light, light reflection and return light. Therefore, it is an object of the present invention to provide a liquid crystal device with stable display image quality without affecting active elements, an easy method for manufacturing a liquid crystal device, and a projection display device including the liquid crystal device.

  In order to solve the above problems, a liquid crystal device according to the present invention includes a pixel region including a plurality of active elements formed in a matrix on one of the pair of substrates, with a liquid crystal material sandwiched between the pair of substrates. A liquid crystal device having a partition wall disposed between the pair of substrates and formed in a boundary region of the pixel region, and a position corresponding to the partition wall between the partition wall and the other substrate of the pair of substrates. A light-shielding film made of a metal film, and a liquid crystal material layer disposed in a recess formed by the partition wall.

  Here, the liquid crystal device of the present invention includes a switching element in a pixel region which is composed of a data line and a scanning line and is an intersection thereof, such as a TFT (Thin Film Transistor) element or a TFD (Thin Film Diode) element formed by a transistor. The active liquid crystal device has an active matrix substrate in which data lines are connected to pixel electrodes selectively and timingly, and a common electrode (counter electrode) is formed on the other substrate (counter substrate). In particular, the present invention is suitable for an active liquid crystal device composed of TFT elements that are preferably used in a projection display device such as a liquid crystal projector.

  In the liquid crystal device of the present invention, a partition is formed in the boundary region (between pixel regions) of the pixel region. The size of the pixel region of the liquid crystal device is about 50 to 500 μm square, and the length of one side is The size is about 1 to 100 μm, preferably about 10 to 50 μm. A partition wall is formed between the pixel regions, and the size of the recess formed by the partition wall is partitioned into a very small region from the entire display region of the liquid crystal device. Here, when the liquid crystal material is injected into the recess, it is possible to easily inject the liquid crystal material having the same volume as the recess volume so as to cover the entire surface of the recess of the very small partition wall, for example, by a droplet discharge device or the like. is there.

Further, the highly reflective film made of a metal film is configured to be disposed between the partition and the other substrate of the pair of substrates at a position corresponding to the partition, for example, on the other substrate (counter substrate) side of the partition In the case of forming on the upper surface, the barrier rib and the highly reflective film have a two-layer structure and can be formed by a photolithography method using the same mask, and can be formed without increasing the number of steps. It is also possible to form a highly reflective film at a position corresponding to the partition wall of the counter substrate. In either case, a highly reflective film is formed between the partition wall and the counter substrate by bonding the counter substrate and the active matrix substrate together.
In addition, the partition wall can be bonded to the counter substrate after being formed on the active matrix substrate, or can be bonded to the active matrix substrate after the partition wall is formed on the counter substrate.

In the configuration of the present invention, the liquid crystal material layer is formed in the recess formed by the partition wall, so that it does not spread after the liquid crystal material is injected and no discharge trace is generated. In addition, even if an ejection mark is generated, it is a boundary with the partition wall and is hidden by the partition wall in the display state, so that the display image quality of the liquid crystal device is not deteriorated.
In addition, even after the liquid crystal device is completed, the liquid crystal material layer is formed in the recess formed by the partition wall, so that the liquid crystal material does not move due to the pressure applied to the liquid crystal device. Thus, a liquid crystal device suitable for a projection display device with good display image quality and high reliability can be obtained without changing the orientation of the liquid crystal material due to the movement of the liquid crystal material.

  In the liquid crystal device according to the present invention, it is more preferable that the partition walls that partition the liquid crystal material layer include a light shielding material. According to this configuration, the light-shielding partition is formed between the pixel unit regions, and the liquid crystal material layer is partitioned and formed in the recess formed by the partition. As a result, the pixel unit is divided with respect to light and electric field, and a liquid crystal device with stable display image quality that is less susceptible to light reflection and electric fields from other pixels can be obtained inside the liquid crystal device. .

  The height of the partition wall of the present invention is set to be equal to the distance between the pair of substrates, and the substrate distance (cell gap) is formed without disposing a sealing material separately or dispersing the spacer material in the liquid crystal material layer. The liquid crystal material can be sealed, and the manufacturing cost can be reduced by shortening the manufacturing process and reducing the material. In this case, the pair of substrates can be bonded to each other by the partition wall by a method in which an adhesive is applied only to the partition wall at the outermost periphery of the display region, and a similar effect can be expected by bringing the other substrate into contact with the partition wall. Furthermore, the strength of the liquid crystal device can be improved by applying an adhesive to the entire partition wall and bonding the pair of substrates. As a result, the thickness of the substrate can be reduced, and a lightweight and thin liquid crystal device can be obtained.

Next, a method for manufacturing a liquid crystal device according to the present invention includes a pixel region having a plurality of active elements formed in a matrix on one of the pair of substrates, with a liquid crystal material sandwiched between the pair of substrates. A method for manufacturing a liquid crystal device, the step of forming a partition at a position corresponding to a boundary region of the pixel region on one of the pair of substrates, and the partition and the position at a position corresponding to the partition And a step of forming a light-shielding film made of a metal film between the other substrate of the pair of substrates and a step of forming a liquid crystal material layer in a recess formed by the partition.
According to such a method of manufacturing a liquid crystal device, a highly reliable liquid crystal device with excellent display image quality that achieves the reduction of manufacturing processes and materials as described above can be manufactured without using new manufacturing processes and materials. Can do.

  In the present invention, it is included that the liquid crystal material layer is formed by discharging a material liquid with a droplet discharge device. In this case, by discharging the liquid crystal material into the partition wall, the liquid crystal material discharge trace does not occur as described above, and the liquid crystal material layer has a uniform thickness, so that no time is required for uniform layer thickness. In addition, the bonding process of a pair of substrates can be continuously performed.

  The liquid crystal device according to the present invention is used as a light valve of a projection display device. In this case, the counter substrate side is an incident side of light from the light source. By mounting the liquid crystal device of the present invention, it is possible to obtain a projection type display device having no display marks of liquid crystal material and good display image quality without being affected by light reflection.

Embodiments according to the present invention will be described with reference to the accompanying drawings. In the following description, an example in which the present invention is applied to a liquid crystal device used as a light valve of a projection display device will be described.
[Liquid Crystal Device]
The liquid crystal device of the present embodiment described below is an active matrix transmissive liquid crystal device using a TFT (Thin Film Transistor) element as a switching element. FIG. 1 is an equivalent circuit diagram of switching elements, signal lines, etc. in a plurality of pixels arranged in a matrix of the transmissive liquid crystal device of this embodiment. FIG. 2 is a plan view of the main part showing the structure of a plurality of pixel groups adjacent to each other on an active matrix substrate on which data lines, scanning lines, pixel electrodes and the like are formed. 3 is a cross-sectional view of the liquid crystal device showing the structure of the active matrix substrate in the cross-sectional view taken along the line AA ′ in FIG. 2, and FIG. 4 is a cross-sectional view taken along the line BB ′ in FIG. It is sectional drawing of the liquid crystal device which shows arrangement | positioning. 3 and 4, the upper side in the drawing is the light incident side, and the lower side in the drawing is the light emitting side. Moreover, in each figure, in order to make each layer and each member into a size that can be recognized on the drawing, each layer or each member is schematically illustrated with a different scale.

  In the liquid crystal device according to the present embodiment, as shown in FIG. 1, a plurality of pixels arranged in a matrix includes a pixel electrode 9 and a TFT that is a switching element for controlling energization of the pixel electrode 9. Each element 30 is formed, and a data line 6 a to which an image signal is supplied is electrically connected to the source of the TFT element 30. Image signals S1, S2,..., Sn to be written to the data line 6a are supplied line-sequentially in this order, or are supplied for each group to a plurality of adjacent data lines 6a.

  In addition, the scanning line 3a is electrically connected to the gate of the TFT element 30, and scanning signals G1, G2,..., Gm are applied to the plurality of scanning lines 3a in a pulse-sequential manner at predetermined timing. The Further, the pixel electrode 9 is electrically connected to the drain of the TFT element 30, and the image signal S1, S2,... Supplied from the data line 6a is turned on by turning on the TFT element 30 as a switching element for a certain period. , Sn is written at a predetermined timing.

  Image signals S1, S2,..., Sn written at a predetermined level on the liquid crystal material through the pixel electrode 9 are held for a certain period with a common electrode described later. The liquid crystal material modulates light and enables gradation display by changing the orientation and order of the molecular assembly according to the applied voltage level. Here, in order to prevent the held image signal from leaking, a storage capacitor 70 is added in parallel with the liquid crystal capacitor formed between the pixel electrode 9 and the common electrode, and the other end of the storage capacitor 70 is The capacitor line 3b is connected.

  Next, based on FIG. 2, the planar structure of the main part of the active matrix substrate of the present embodiment will be described. As shown in FIG. 2, a rectangular pixel electrode 9 (dotted line portion 9A) made of a transparent conductive material such as indium tin oxide (hereinafter abbreviated as ITO) is formed on an active matrix substrate. Are provided in a matrix, and data lines 6a, scanning lines 3a, and capacitor lines 3b are provided along the vertical and horizontal boundaries of the pixel electrode 9, respectively. In the present embodiment, each pixel electrode 9 and a region where the data line 6a, the scanning line 3a, the capacitor line 3b, and the like arranged so as to surround each pixel electrode 9 are formed is a pixel region. In addition, the vicinity of the region where the data line 6a, the scanning line 3a, and the capacitor line 3b are formed becomes a boundary region of the pixel region, and the display can be performed for each pixel arranged in a matrix.

  The data line 6a is electrically connected to a source region (described later) through a contact hole 5 in the semiconductor layer 1a made of, for example, a polysilicon film constituting the TFT element 30, and the pixel electrode 9 is connected to the semiconductor layer 1a. Among these, it is electrically connected to a drain region described later via a contact hole 8. In addition, the scanning line 3a is disposed so as to face a channel region (a region with a diagonal line rising to the left in the figure), which will be described later, of the semiconductor layer 1a. The scanning line 3a serves as a gate electrode at a portion facing the channel region. Function.

  The capacitor line 3b is formed from a main line portion extending in a substantially straight line along the scanning line 3a (that is, a first region formed along the scanning line 3a in a plan view) and a portion intersecting the data line 6a. And a protruding portion (that is, a second region extending along the data line 6 a when viewed in a plan view) protruding toward the previous stage (upward in the drawing) along the data line 6 a. In FIG. 2, a plurality of first light shielding films 11 a are provided in a region indicated by a diagonal line rising to the right. The first light shielding film 11 a is electrically connected to the capacitor line 3 b through the contact hole 13.

  Next, a cross-sectional structure of the liquid crystal device of the present embodiment will be described with reference to FIG. FIG. 3 is a cross-sectional view taken along the line A-A ′ of FIG. 2 as described above, and is a cross-sectional view showing a configuration of a region where the TFT element 30 is formed. In the liquid crystal device of the present embodiment, a liquid crystal material layer is sandwiched between the active matrix substrate 10 and the counter substrate 20 disposed to face the active matrix substrate 10, but the cross section along the line AA ′ is the boundary region of the pixel region The partition wall 15 is formed. In this embodiment, the partition wall 15 is made of a resin such as polyimide containing a light shielding material such as a pigment by a photolithography method.

  The active matrix substrate 10 is mainly composed of a substrate body 10A made of a translucent material such as quartz, a TFT element 30, a pixel electrode 9, and an alignment film 40 formed on the surface of the partition wall 15 side. The counter substrate 20 includes a substrate body 20A made of a translucent material such as glass and quartz, and a second light shielding film 23 made of a metal film at a position facing the TFT element 30 between the pixel regions formed on the surface of the partition wall 15. The common electrode 21 and the alignment film 60 formed on the surface of the partition wall 15 are mainly used. The substrates 10 and 20 are held at predetermined substrate intervals via the partition walls 15.

  In the active matrix substrate 10, pixel electrodes 9 are provided on the surface of the partition wall 15, and pixel switching TFT elements 30 that perform switching control of the pixel electrodes 9 are provided at positions adjacent to the pixel electrodes 9. The pixel switching TFT element 30 has an LDD (Lightly Doped Drain) structure, and includes a scanning line 3a, a channel region 1a ′ of the semiconductor layer 1a in which a channel is formed by an electric field from the scanning line 3a, and the scanning line 3a. A gate insulating film 2 that insulates the semiconductor layer 1a, a data line 6a, a low concentration source region 1b and a low concentration drain region 1c of the semiconductor layer 1a, and a high concentration source region 1d and a high concentration drain region 1e of the semiconductor layer 1a. ing.

  A contact hole 5 leading to the high concentration source region 1d and a contact hole 8 leading to the high concentration drain region 1e are opened on the substrate body 10A including the scanning line 3a, the capacitance line 3b, and the gate insulating film 2. The second interlayer insulating film 4 is formed. That is, the data line 6 a is electrically connected to the high concentration source region 1 d through the contact hole 5 that penetrates the second interlayer insulating film 4.

  Further, on the data line 6a and the second interlayer insulating film 4, a third interlayer insulating film 7 having a contact hole 8 leading to the high concentration drain region 1e is formed. That is, the high concentration drain region 1 e is electrically connected to the pixel electrode 9 through the contact hole 8 that penetrates the second interlayer insulating film 4 and the third interlayer insulating film 7.

  In addition, on the surface of the active matrix substrate 10 on the partition wall 15 side of the substrate body 10A, the region where the pixel switching TFT elements 30 are formed is transmitted through the active matrix substrate 10 and the lower surface of the active matrix substrate 10 shown in the drawing (active matrix). The return light reflected by the substrate 10 and the air) and returning to the partition wall 15 side is prevented from entering at least the channel region 1a ′ and the low concentration source / drain regions 1b and 1c of the semiconductor layer 1a. A first light shielding film 11a is provided.

  Further, a first interlayer insulation for electrically insulating the semiconductor layer 1a constituting the pixel switching TFT element 30 from the first light shielding film 11a is provided between the first light shielding film 11a and the pixel switching TFT element 30. A film 12 is formed. Further, as shown in FIG. 2, in addition to providing the first light shielding film 11a on the active matrix substrate 10, the first light shielding film 11a is electrically connected to the capacitor line 3b at the preceding stage or the subsequent stage through the contact hole 13. Configured to connect to.

  Further, on the outermost surface of the active matrix substrate 10 on the partition wall 15 side, that is, on the pixel electrode 9 and the third interlayer insulating film 7, an alignment film 40 for controlling the alignment of liquid crystal molecules in the liquid crystal material layer when no voltage is applied. Is formed. Therefore, in the region having such TFT elements 30, a plurality of minute irregularities or steps are formed on the outermost surface of the active matrix substrate 10 on the partition 15 side, that is, on the surface on which the partition 15 is formed. . On the active matrix substrate 10 having such a step, it is possible to easily form the partition 15 with a flat surface on the counter substrate 20 side according to the thickness of the liquid crystal material layer by a spin coating method or the like.

  On the other hand, the counter substrate 20 is provided with a second light shielding film 23 made of a metal film, such as an aluminum film, on the surface of the substrate body 20A on the partition wall 15 side. The second light-shielding film 23 is disposed between the pixel region other than the region where the data line 6a, the scanning line 3a, and the pixel switching TFT element 30 are formed, that is, the opening region of each pixel portion. The incident light is configured to prevent intrusion into the channel region 1a ', the low concentration source region 1b, and the low concentration drain region 1c of the semiconductor layer 1a of the pixel switching TFT element 30. In addition, the second light-shielding film 23 such as an aluminum film is configured to reflect strong light from the light source that is incident light and prevent the temperature of the liquid crystal device from rising. A common electrode 21 made of ITO or the like is formed over substantially the entire surface of the substrate body 20A on which the second light shielding film 23 is formed, and a liquid crystal material layer when no voltage is applied is formed on the partition 15 side. An alignment film 60 for controlling the alignment of the liquid crystal molecules is formed.

  Thus, in the liquid crystal device of the present invention, the pixel switching TFT element 30 is formed between the pixel regions as shown in the cross-sectional view of FIG. A second light-shielding film 23 made of a metal film that reflects light between pixel regions is formed on the counter substrate 20 on the upper side, that is, the light incident side in FIG. 3, and the distance between the active matrix substrate 10 and the counter substrate 20 is maintained. In addition, a partition wall 15 is formed to prevent light from entering between the pixel regions. Further, the active matrix substrate 10 is arranged so that the data line 6a prevents the light from entering the TFT element 30 from the light incident side, and further prevents the return light from the light emitting side from entering the TFT element 30. The first light shielding film 11a is arranged as much as possible. Between the pixel regions, a light shielding material is disposed in the entire cross-sectional region of the counter substrate 20 and the active matrix substrate 10 including the inside of the TFT elements, so that light is not incident on the TFT elements 30.

  As a result, strong light from the light incident side is reflected by the second light shielding film made of metal, and heat generation in the liquid crystal device can be reduced. Further, the partition wall 15, the data line 6a, and the first light shielding film 11a are disposed between the pixel regions in which the TFT elements 30 are disposed, and return light and other reflected light are transmitted to the channel 1a 'of the TFT element 30 and the low concentration source. Intrusion into the region 1b and the low concentration drain region 1c is prevented. As a result, an increase in leakage current of the TFT element 30 due to light can be prevented, and a liquid crystal device with good image quality can be obtained.

  FIG. 4 is a cross-sectional view taken along line B-B ′ of FIG. 2 and shows a cross section of the pixel region partitioned by the partition 15 between the pixel regions. As shown in FIG. 4, partition walls 15 are arranged between the pixel regions so as to maintain a distance between the active matrix substrate 10 and the counter substrate 20. The active matrix substrate 10 and the counter substrate 20 thus configured are arranged so that the pixel electrode 9 and the counter electrode 21 face each other, and the space between these substrates is surrounded by the partition wall 15. The liquid crystal material layer 50 is sealed and sandwiched. The liquid crystal material layer 50 is configured to take a predetermined alignment state by rubbing the alignment films 40 and 60 in a state where an electric field from the pixel electrode 9 is not applied. The liquid crystal material layer 50 is composed of, for example, a mixture of one kind or several kinds of nematic liquid crystals.

  Similarly, in FIG. 4, between the pixel regions in the active matrix substrate 10, the first light-shielding film 11a is disposed on the lower surface side (substrate body 10A side) of the TFT channel 1a ', and the upper surface side (partition wall 15 side) is A data line 6a is arranged. Further, a partition wall 15 is disposed between the pixel regions of the active matrix substrate 10, and a second light-shielding layer 23 made of a metal film is disposed between the partition wall 15 and the counter substrate 20.

  As a result, the region formed by the pixel electrode 9, the liquid crystal material layer 50, and the counter electrode 21, which is a pixel region, is structurally partitioned by the partition wall 15. Then, the strong light from the upper light source between the pixel regions in FIG. 4 is reflected by the second light shielding film 23 which is a metal film, and the light incident between the pixel regions due to reflection or the like is absorbed by the partition wall 15, Light incident on the TFT element region is shielded by the data line 6a and the first light shielding film 11a. The voltage application between the pixel electrode 9 and the counter electrode 21 is applied within a pixel region surrounded by the partition wall 15. In other words, the electric field from the adjacent pixel electrode 9 is applied through the partition wall 15, and the liquid crystal material layer 50 is less likely to be affected by other pixel electrodes.

  Note that the surface of the counter substrate 20 and the active matrix substrate 10 on the light incident side or the light emitting side has a type of the liquid crystal material layer 50 to be used, that is, operations such as a TN (twisted nematic) mode, an STN (super TN) mode, and the like. Depending on the mode and the normally white mode / normally black mode, a polarizing film, a retardation film, a polarizing plate, and the like are arranged in a predetermined direction.

  The liquid crystal device shown here is used in, for example, a projection display device (liquid crystal projector) described later. In this case, three liquid crystal devices are respectively used as RGB light valves, and light of each color separated through RGB color separation dichroic mirrors is incident on each of the liquid crystal devices as projection light. Will be. Therefore, no color filter is formed in the liquid crystal devices of the above-described embodiments.

  Next, as shown in FIG. 5, an embodiment in which a microlens 500 is formed in each of the regions facing the pixel electrode 9 in the counter substrate 200 will be described. In FIG. 5, the counter substrate 200 on which the microlens 500 is formed is configured as a substrate in which a first transparent substrate 200 </ b> A and a second transparent substrate 250 are bonded together with a microlens layer 201. The microlens 500 is formed by forming a concave curved surface portion formed by wet etching the first transparent substrate 200A into a lens shape by, for example, photolithography. Next, a transparent resin having a refractive index different from that of the first transparent substrate 200A is applied to the concave curved surface portion by thermosetting or photocuring, and the second transparent substrate 250 is stacked thereon and cured by heat or light. Thus, the microlens layer 201 and the counter substrate 200 are formed. The boundary between the microlens layer 201 having the different refractive index and the first transparent substrate 200A functions as the microlens 500.

  In FIG. 5, as shown by an arrow L11, the incident light that has been lost by being shielded by the second light shielding film 23, the TFT 30 or the like is condensed by the microlens 500 on the opening of each pixel, thereby reducing the amount of transmitted light. In addition, the channel region 1a ′ of the TFT 30 and the drain end are prevented from being irradiated with strong light. Even in this case, the data lines 6 a and the first light shielding film 11 a in the active matrix substrate 10, the partition wall 15 between the active matrix substrate 10 and the counter substrate 200, and the second light shielding film 23 made of the metal film of the counter substrate 200 are provided. It is formed similarly. Accordingly, in the pixel area, the amount of transmitted light is increased by condensing by the microlens 500, while incident light is reflected by the second light shielding layer 23 between the pixel areas, and by the partition wall 15, the data line 6a, and the first light shielding film 11a. Light can be prevented from entering the TFT element, and a bright and high-quality image can be displayed, and a highly reliable liquid crystal device can be obtained.

[Method of manufacturing liquid crystal device]
Next, a method for manufacturing a liquid crystal device will be described with reference to FIG.
As shown in step S11 of FIG. 6, the first light shielding film 11a, the first interlayer insulating film 12, the semiconductor layer 1, the gate insulating film 2, the channel region 1a, and the source region are formed on the lower substrate body 10A made of quartz or the like. 1d and 1b, drain regions 1e and 1c, scanning line 3a, second interlayer insulating film 4, contact hole 5, data line 6a, third interlayer insulating film 7, contact hole 8, pixel electrode 9 of TFT element 30, alignment film 40 is formed and a rubbing process is performed to form a lower substrate 10 (active matrix substrate).

  Next, in step S <b> 12 of FIG. 6, the partition wall 15 is formed on the active matrix substrate 10. The partition wall 15 is applied to the active matrix substrate 10 with an insulating resin material such as polyimide, for example, by a spin coat method or the like to a height that determines the distance between the substrates, that is, the thickness of the liquid crystal material layer. Are formed between the pixel regions in a predetermined shape. The active matrix substrate 10 is in a substantially planar state although the TFT elements 30 are formed and there are minute steps, and it can be easily applied on the active matrix substrate 10 by a spin coating method or the like. Further, the light shielding material can be mixed into the partition wall 15 by mixing a black pigment or the like with the resin material.

  In addition, when the polyimide material of the partition wall 15 is applied on the alignment film 40 that has been rubbed, and the polyimide material layer of the partition wall 15 is etched into a predetermined shape by photolithography, the alignment film 40 is sufficiently cured by heat treatment. On the other hand, since the polyimide material layer of the partition wall 15 is formed by etching by photolithography, it is thermally cured to such an extent that the shape can be maintained. Therefore, when the polyimide material layer of the partition wall 15 is etched, the alignment film 40 can be selectively etched, and only the polyimide material layer of the partition wall 15 can be etched to form a predetermined shape. .

Here, the alignment film 40 and the alignment film 60 to be described later are formed as described above when necessary depending on the liquid crystal material to be used. Further, the alignment film 40 may be formed after the partition wall 15 is formed in step S12 of FIG. 6, or may be formed by discharging a liquid mixture of the alignment film material and the solvent with a droplet discharge device or the like. Alternatively, it can be formed by a method such as oblique deposition of SiO ₂ .

Next, in step S <b> 13 of FIG. 6, a liquid crystal material is injected into the recess of the partition wall 15.
Here, the injection state of the liquid crystal material will be described with reference to FIG. FIG. 7 shows an example in which a liquid crystal material is injected by a droplet discharge device, for example, an ink jet device, and an expected landing shape 51 of the liquid crystal material droplet is shown by a two-dot chain line in the recess of the partition wall 15. Here, the liquid crystal material is injected by discharging a liquid crystal material having the same volume as that of each recess of the partition wall 15 in accordance with the shape of the partition wall 15. Specifically, the amount of droplets and the discharge amount are set so that the size of one side of the recess of the partition wall 15 is between the size of the droplet immediately after being discharged from the droplet discharge device and the size of the assumed landing shape 51. Set conditions. FIG. 7 shows an example in which the size of one side of the recess of the partition wall 15 and the assumed landing shape 51 of the liquid crystal material droplet are the same size. Further, FIG. 7 shows a state in which two drops are ejected, and a gap is generated between the partition wall 15 and the liquid crystal material is further filled in the recess of the partition wall 15, that is, the volume of the recess. The liquid crystal material having the same volume as the liquid crystal material is discharged in an overlapping manner. By discharging droplets in this way, the liquid crystal material can be filled in the recesses of the partition walls 15.

  At this time, even if the liquid crystal material is discharged with a single drop to fill the concave portion of the partition wall 15 or with a few drops, the liquid crystal material does not move within the concave portion of the partition wall 15. This is because the viscosity of the liquid crystal material is high, and in the discharge by the normal ink jet method, the discharge ends before the liquid crystal material moves. As a result, it is possible to form a liquid crystal material layer in the partition wall 15 without generating a discharge trace of the liquid crystal material layer.

  On the other hand, as shown in FIG. 6, the upper substrate 20 (counter substrate) is subjected to steps S <b> 21 and S <b> 22 which are steps of forming the upper substrate 20 in parallel with steps S <b> 11 to S <b> 13 which are steps of forming the lower substrate 10. . As shown in step S21 in FIG. 6, a metal film such as aluminum is formed on the upper substrate body 20A by using a vapor deposition method or a sputtering method, and is formed into a predetermined shape (between pixel regions) by a photolithography method. 2 The light shielding film 23 is formed.

  Next, in step S22 of FIG. 6, the counter electrode 21 is formed on the upper substrate body 20A. The counter electrode 21 is formed by forming a transparent conductive film such as ITO on the upper substrate body 20A by sputtering or the like, forming it in a predetermined shape by photolithography or the like, and then forming an alignment film 60 and rubbing it. The upper substrate 20 is created.

After injecting the liquid crystal material into the recess of the partition wall 15 of the lower substrate 10, an adhesive is applied to the upper portion of the partition wall 15 in step S4 of FIG. 6, the lower substrate 10 and the upper substrate 20 are bonded together, and the liquid crystal material is sealed. To do.
In the present embodiment, as shown in FIG. 7, the droplet shape 51 of the liquid crystal material is formed without moving after ejection, so that no ejection trace is generated. Even if a discharge mark is generated, the size is 50 to 500 μm square which is the size of the pixel region, and the generated portion is highly likely to be near the boundary with the partition wall 15. If it is included, the display image quality is not affected at all. In addition, since the liquid crystal material layer does not move, it is not necessary to wait for the surface to become uniform after the liquid crystal material layer is discharged, and the lower substrate 10 and the upper substrate 20 can be continuously bonded, and the manufacturing time can be increased. Can be shortened.
In the liquid crystal device manufacturing method of the present embodiment, an adhesive is applied to the upper part of the partition wall 15, and the lower substrate 10 and the upper substrate 20 are bonded and sealed. Generally, sealing materials and spacers used for sealing are used. There is no need for materials and the like, and the manufacturing process can be shortened and manufacturing materials can be reduced.

  In the present embodiment, the second light shielding film 23 made of a metal film is formed on the counter substrate 20. However, after the partition 15 is formed on the active matrix substrate 10 and the metal film is formed thereon, photo By forming the second light-shielding film 23 and the partition wall 15 by continuously etching the metal film and the partition wall material layer by lithography or the like, it can be formed without increasing the number of manufacturing steps. Further, a metal film and a partition wall material layer are formed on the counter substrate 20 in the same manner.

[Configuration of Projection Display Device]
FIG. 8 is a schematic configuration diagram showing an optical system of a projection display device (projector) using the liquid crystal device 1 to which the present invention is applied as a light valve.

  As shown in FIG. 8, a lamp unit 1102 including a white light source such as a halogen lamp is provided inside the projector 1100. The projection light emitted from the lamp unit 1102 is separated into three primary colors of RGB by three mirrors 1106 and two dichroic mirrors 1108 disposed therein, and light valves 100R, 100G corresponding to the primary colors and 100B, respectively. Here, the configuration of the light valves 100R, 100G, and 100B is the same as that of the liquid crystal device described above, and is driven by R, G, and B primary color signals supplied from an image signal processing circuit (not shown). . In addition, B light has a longer optical path than other R and G colors, so that light is guided through a relay lens system 1121 including an entrance lens 1122, a relay lens 1123, and an exit lens 1124 to prevent loss. It is burned.

  In the projection display device configured as described above, light modulated by the light valves 100R, 100G, and 100B is incident on the dichroic prism 1112 from three directions. In the dichroic prism 1112, the R and B light beams are refracted at 90 degrees, while the G light beam goes straight. Therefore, as a result of the synthesis of the images of the respective colors, a color image is projected onto the screen 1120 via the projection lens 1114.

  Since light corresponding to the primary colors R, G, and B is incident on the light valves 100R, 100G, and 100B by the dichroic mirror 1108, it is not necessary to provide a color filter as described above.

1 is an equivalent circuit diagram illustrating a liquid crystal device according to an embodiment of the present invention. FIG. 2 is a plan view illustrating a structure of a pixel group in the liquid crystal device of FIG. 1. FIG. 2 is a cross-sectional view showing a main part of an active element of the liquid crystal device of FIG. 1. FIG. 2 is a cross-sectional view illustrating a main part of the liquid crystal device of FIG. 1. Sectional drawing which shows the principal part of the liquid crystal device of other embodiment of FIG. Process explanatory drawing which shows an example about the manufacturing method of the liquid crystal device of FIG. Explanatory drawing which shows the specific aspect of the dripped liquid crystal material. The schematic block diagram of the projection type display apparatus which used the liquid crystal device of this invention as a light valve.

Explanation of symbols

  3 a scanning line 6 a data line 9 pixel electrode 10 TFT array substrate 15 partition wall 20 counter substrate 30 switching TFT element 50 liquid crystal material layer

Claims (6)

A liquid crystal device having a pixel region having a plurality of active elements formed in a matrix on one of the pair of substrates, with a liquid crystal material sandwiched between the pair of substrates,
A partition wall disposed between the pair of substrates and formed in a boundary region of the pixel region;
A light shielding film made of a metal film disposed between the partition and the other of the pair of substrates at a position corresponding to the partition;
A liquid crystal material layer disposed in a recess formed by the partition;
A liquid crystal device comprising:   The liquid crystal device according to claim 1, wherein the partition includes a light shielding material.   The liquid crystal device according to claim 1, wherein a height of the partition wall is set to be equal to a distance between the pair of substrates. A method of manufacturing a liquid crystal device having a pixel region having a plurality of active elements formed in a matrix on one of the pair of substrates, with a liquid crystal material sandwiched between the pair of substrates,
Forming a partition wall at a position corresponding to a boundary region of the pixel region on any one of the pair of substrates;
Forming a light shielding film made of a metal film between the partition and the other substrate of the pair of substrates at a position corresponding to the partition;
Forming a liquid crystal material layer in the recess formed by the partition;
A method for manufacturing a liquid crystal device, comprising:   The method of manufacturing a liquid crystal device according to claim 4, wherein the liquid crystal material layer is formed by a droplet discharge device. 5. A projection type display device, wherein the liquid crystal device according to claim 1 is used as a light valve, and the other substrate side of the pair of substrates is an incident side of light from a light source.

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