JP2006047600A - Liquid crystal display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the contrast from falling due to irregular liquid crystal arrangements. <P>SOLUTION: This liquid crystal display has an active matrix substrate 22, an opposite substrate 23 disposed facing the active matrix substrate 22, and a liquid crystal layer 24 provided between the active matrix substrate 22 and the opposite substrate 23. The main surfaces facing the liquid crystal layer 24 of the active matrix substrate 22 and/or of the opposite substrate 23 have the areas changing discontinuously (boundaries 38a-38d, edges 39a-39d, edges 40a-40d, side walls 44a, 44b), and a light shading section (gate wiring 26, source wiring 33, auxiliary capacitance wiring 28) to prevent the light from the active matrix substrate 22 or the opposite substrate 23 to enter the liquid crystal layer 24 from passing through the above stepped sections to the active matrix substrate 22. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a liquid crystal display device.

  In recent years, portable information devices including liquid crystal display devices such as mobile phones and PDA terminals have been rapidly developed. Accordingly, liquid crystal display devices used in these portable information devices are required to have high display quality and low power consumption regardless of the environment such as outdoors or indoors. As a liquid crystal display device satisfying these requirements, a reflection / transmission type liquid crystal display device has attracted attention. The reflection / transmission type liquid crystal display device includes two regions of a reflection region and a transmission region in one picture element. The reflection area is an area for displaying an image by reflecting light incident from outside in the apparatus. On the other hand, the transmission region is a region for displaying an image by transmitting light generated in the backlight in the apparatus through the liquid crystal layer. Hereinafter, a conventional reflection / transmission liquid crystal display device will be described in detail with reference to the drawings. Here, FIG. 22 is a diagram showing a cross-sectional structure of one picture element of a conventional reflective / transmissive liquid crystal display device.

  The conventional reflective / transmissive liquid crystal display device shown in FIG. 22 includes an active matrix substrate 1002, a counter substrate 1003, and a liquid crystal layer 1004. The counter substrate 1003 is disposed so as to face the active matrix substrate 1002. In addition, the liquid crystal layer 1004 is provided between the counter substrate 1003 and the active matrix substrate 1002.

  The active matrix substrate 1002 includes a glass substrate 1005, a gate electrode 1006, a gate insulating film 1007, a semiconductor layer 1008, semiconductor contact layers 1009a and 1009b, a source electrode 1010, a drain electrode 1011, an interlayer insulating film 1012, a transparent electrode 1013, and a reflective electrode. 1014 as well as contact portion 1015. Hereinafter, main components of the active matrix substrate 1002 will be described.

  The transparent electrode 1013 is disposed in a transmission region T (T region in FIG. 22) that displays light by transmitting light incident from the glass substrate 1005 side to the liquid crystal layer 1004 side. The reflective electrode 1014 is disposed in a reflective region R (R region in FIG. 22) that reflects light incident from the counter substrate 1003 side and displays an image. The gate electrode 1006, the gate insulating film 1007, the semiconductor layer 1008, the semiconductor contact layers 1009a and 100b, the source electrode 1010, the drain electrode 1011 and the interlayer insulating film 1012 constitute a TFT (Thin Film Transistor).

  The counter substrate 1003 includes a glass substrate 1018 and a transparent electrode 1019. The transparent electrode 1019 is formed on the main surface of the glass substrate 1018 on the liquid crystal layer 1004 side. Note that an alignment film (not shown) is disposed on the boundary between the active matrix substrate 1002 and the liquid crystal layer 1004 and on the boundary between the counter substrate 1003 and the liquid crystal layer 1004. Further, when the reflective / transmissive liquid crystal display device can perform color display, a colored layer is disposed between the glass substrate 1018 and the transparent electrode 1019.

  The operation of the conventional reflection / transmission type liquid crystal display device configured as described above will be briefly described below. Note that a backlight (not shown) is disposed on the back surface of the liquid crystal panel (below the active matrix substrate 1002).

  When the liquid crystal panel displays an image, light is emitted from the backlight to the liquid crystal panel. At this time, in order to display a desired image on the liquid crystal panel, a voltage is applied between the transparent electrode 1013 and the transparent electrode 1019 and between the reflective electrode 1014 and the transparent electrode 1019. The liquid crystal layer 1004 has an orientation corresponding to the magnitude of the applied voltage for each picture element. Thereby, in each picture element, the transmittance of the liquid crystal layer 1004 is controlled to a desired transmittance.

  As described above, when the transmittance of the liquid crystal layer 1004 is controlled in each picture element, the light output from the backlight in the transmissive region T is an amount of light corresponding to the transmittance of the liquid crystal layer 1004, and the active matrix substrate 1002. The liquid crystal layer 1004 and the counter substrate 1003 are transmitted. On the other hand, in the reflective region R, light incident from above the counter substrate 1003 is reflected by the reflective electrode 1014 and is emitted above the counter substrate 1003 with an amount of light corresponding to the transmittance of the liquid crystal layer 1004. Thereby, a desired image is displayed on the liquid crystal panel.

  Here, the conventional reflection / transmission liquid crystal display device employs a multi-gap structure in which a step is provided in the vicinity of the boundary between the reflection region R and the transmission region T. This is to make the optical path length of the liquid crystal layer 1004 in the reflection region R equal to the optical path length of the light in the transmission region T in the liquid crystal layer 1004. This will be described in detail below.

  As described above, in the transmissive region T, the light output from the backlight passes through the liquid crystal layer 1004 once. On the other hand, in the reflection region R, external light passes through the liquid crystal layer 1004, is reflected by the reflective electrode 1014, and passes through the liquid crystal layer 1004 again. That is, in the reflection region R, external light passes through the liquid crystal layer 1004 twice. Therefore, in order to make the optical path length of the light transmitted through the transmission region T in the liquid crystal layer 1004 equal to the optical path length of the light reflected in the reflection region R in the vicinity of the boundary between the reflection region R and the transmission region T. A protrusion 1016 is formed in the reflection region R by providing a step. Thereby, the layer thickness of the liquid crystal layer 1004 in the reflection region R is made thinner than the layer thickness of the liquid crystal layer 1004 in the transmission region T.

As described above, since the conventional reflection / transmission liquid crystal display device uses backlight and external light, it is possible to obtain a bright and high-quality display both indoors and outdoors. It becomes. Further, in the conventional reflection / transmission liquid crystal display device, it is possible to reduce power consumption by performing display using only outside light outdoors.
JP 2002-229016 A

  However, the conventional reflective / transmissive liquid crystal display device has a problem that it is difficult to obtain high contrast. This will be described in detail below.

  The above conventional reflection / transmission liquid crystal display device has a structure in which the directivity of reflected light is reduced (regular reflection is reduced) in order to obtain white light that is easy to see like paper. Specifically, as shown in FIG. 22, irregularities are formed on the reflective electrode 1014 in the transmissive region T of the reflective / transmissive liquid crystal display device. Thereby, the light reflected by the reflective electrode 1014 is scattered. As a result, it is possible to obtain white light that is easy to see like paper in the conventional reflective / transmissive liquid crystal display device.

  However, when unevenness is formed on the reflective electrode 1014, the main surface of the reflective electrode 1014 (that is, the liquid crystal layer 1004 out of the main surface of the active matrix substrate 1002) at the boundary between the uneven portion and the flat portion. A portion where the shape of the main surface (contacting) changes discontinuously occurs. Thus, when the main surface of the reflective electrode 1014 changes discontinuously, liquid crystal alignment disorder occurs at such a location. As a result, the contrast of the reflection / transmission liquid crystal display device is lowered.

  In addition, a portion where the main surface of the active matrix substrate 1002 is discontinuously changed due to other factors and a region in the vicinity thereof also cause a decrease in contrast of the transflective liquid crystal display device. Specifically, at the step provided at the boundary between the reflective region R and the transmissive region T, an inclined side wall 1016a is formed as shown in FIG. In such a side wall 1016a, the optical path length of the light transmitted through the liquid crystal layer 1004 is disturbed. As a result, the contrast of the reflection / transmission liquid crystal display device is lowered.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a reflection / transmission type liquid crystal display device capable of suppressing a decrease in contrast caused by the presence of a discontinuously changing shape generated on a main surface of a substrate. .

In the liquid crystal display device according to the present invention, the first substrate, the second substrate disposed so as to face the first substrate, and the first substrate and the second substrate are provided. A main surface on the liquid crystal layer side of the first substrate and / or a main surface on the liquid crystal layer side of the second substrate includes a portion where the main surface shape changes discontinuously. And a light blocking means for preventing light incident on the liquid crystal layer from the second substrate side from passing through the portion where the main surface shape changes discontinuously and transmitting to the first substrate side. ing.
In addition, the liquid crystal display device according to the present invention is defined in a two-dimensional array on the main surface of the second substrate, and transmits light incident on the liquid crystal layer from the first substrate side. Light that is defined in a two-dimensional array on the main surface of the second substrate, and is incident on the liquid crystal layer from the second substrate side, and a plurality of reflection regions that reflect the substrate to display an image And a plurality of transmissive areas for transmitting images to the first substrate side and displaying images.

  In the liquid crystal display device according to the present invention, the portion where the main surface shape changes discontinuously is such that the thickness of the liquid crystal layer in the reflective region is smaller than the thickness of the liquid crystal layer in the transmissive region. In addition, a step formed on the main surface of the first substrate on the liquid crystal layer side and / or the main surface of the second substrate on the liquid crystal layer side may be used.

  In the liquid crystal display device according to the present invention, a wiring is formed on the second substrate from a light-shielding material, and the light shielding unit includes the wiring among the wirings formed on the second substrate. The wiring formed in the vicinity of the step may be used.

  In the liquid crystal display device according to the present invention, the plurality of transmissive regions and the plurality of reflective regions constitute a plurality of pixel regions adjacent to each other, and correspond to each of the pixel regions. A plurality of switching elements may be further provided, and the wiring may be electrically connected to each of the switching elements.

  Further, in the liquid crystal display device according to the present invention, the transmission region and the reflection region constitute one picture element region adjacent to each other, and the light shielding means is in the vicinity of the step, A light shielding mask formed of a light shielding material on the first substrate or the second substrate may be used.

  In the liquid crystal display device according to the present invention, the second substrate has an interlayer insulating film having a flat shape in the transmissive region and a concavo-convex shape in the reflective region on the main surface on the liquid crystal layer side. The portion where the main surface shape changes discontinuously may be a boundary between the flat shape of the interlayer insulating film and the uneven shape of the interlayer insulating film.

  The liquid crystal display device according to the present invention further includes a reflective film formed on the main surface of the second substrate on the liquid crystal side, and the portion where the main surface shape changes discontinuously is the second film. The edge part of the said reflecting film on the main surface by the side of the liquid crystal of a board | substrate may be sufficient.

  As described above, according to the liquid crystal display device according to the present invention, light is prevented from passing through the portion where the main surface shape changes discontinuously. As a result, the liquid crystal display device of the present invention has improved contrast characteristics compared to the conventional liquid crystal display device.

The basic configuration of the reflection / transmission liquid crystal display device according to the present invention will be described below. First, a reflection / transmission liquid crystal display device according to the present invention includes a counter substrate (first substrate), an active matrix substrate (second substrate) disposed to face the counter substrate, a counter substrate, And a liquid crystal layer provided between the active matrix substrate. Furthermore, the main surface on the liquid crystal layer side of the counter substrate and / or the main surface on the liquid crystal layer side of the active matrix substrate includes a portion where the main surface shape changes discontinuously. The presence of such a portion where the main surface shape changes discontinuously causes a reduction in display contrast in the reflection / transmission liquid crystal display device. Therefore, in the reflection / transmission liquid crystal display device according to the present invention, light incident on the liquid crystal layer from the active matrix substrate side passes through the portion where the main surface shape changes discontinuously and is transmitted to the counter substrate side. A light shielding part is provided for prevention. In the following, a specific configuration of the liquid crystal display device according to the present invention will be described by dividing it into a plurality of embodiments.
(First embodiment)
The liquid crystal display device according to the first embodiment of the present invention will be described below with reference to the drawings. Here, FIG. 1 is a view of the active matrix substrate 22 as viewed from vertically above. FIG. 2 is a diagram showing a state in which the counter substrate 23 is bonded to the active matrix substrate 22 shown in FIG. 3 is a cross-sectional view taken along the line II in FIG. 1 and FIG. 4 is a cross-sectional view taken along the line II-II in FIG. 1 and FIG.

  In the liquid crystal display device according to the present embodiment, picture element regions as shown in FIG. 1 are arranged in an array (more specifically, in a matrix). The picture element area is an area corresponding to a picture element which is the minimum unit of display, and there are areas having three colors of R (red), G (green), and B (blue). Each of the three picture element areas of the R picture element area, the G picture element area, and the B picture element area constitutes one pixel area.

  The picture element region includes a reflection region R and a transmission region T as shown in FIGS. As shown in FIGS. 1 and 2, the reflection region R is defined in a state of being arranged in a two-dimensional shape (more specifically, a matrix shape) on the main surface of the active matrix substrate 22, and the liquid crystal layer from the counter substrate 23 side. The light incident on 24 is reflected toward the counter substrate 23 to display an image. On the other hand, as shown in FIGS. 1 and 2, the transmissive region T is defined in a state of being arranged in a two-dimensional shape (more specifically, in a matrix shape) on the main surface of the active matrix substrate 22, and the active matrix substrate 22 side. Then, the light incident on the liquid crystal layer 24 is transmitted to the counter substrate 23 side to display an image. And as above-mentioned, the transmissive area | region T and the reflective area | region R comprise a pixel area | region by what adjoins mutually. Hereinafter, a detailed configuration within the picture element region will be described.

In the reflection / transmission liquid crystal display device according to this embodiment, as shown in FIG. 3, an active matrix substrate 22, a liquid crystal layer 24, and a counter substrate 23 are laminated in order from the bottom to the top. The active matrix substrate 22 includes a glass substrate 25, a gate wiring 26, an auxiliary capacitance wiring 28, a gate insulating film 30, a source wiring 33, a TFT (Thin Film Transistor) 36, a protective film 37, an interlayer insulating film 38, a transparent electrode 39, and a reflection. An electrode 40 is included. In addition, one TFT 36 is provided as a switching element in each picture element region in order to display an image in the picture element region. The TFT 36 includes a gate electrode 27, a semiconductor layer 31, a semiconductor contact layer 32, a source electrode 34 and a drain electrode 35. The counter substrate 23 includes a glass substrate 42, a colored layer 43, a convex portion 44, and a transparent electrode 45.
(About the structure of the active matrix substrate 22)
First, details of the active matrix substrate 22 will be described with reference mainly to FIG. In a predetermined region on the glass substrate 25, a gate wiring 26 (not shown in FIG. 3), a gate electrode 27, an auxiliary capacitance wiring 28, and an auxiliary capacitance electrode 29 are formed of a light-shielding conductive material (for example, Ta (tantalum)). Be placed. As shown in FIG. 2, the gate wirings 26 are arranged in a grid pattern on the main surface of the active matrix substrate 22 and are electrically connected to the TFTs 36 (specifically, the gate electrodes 27). The auxiliary capacity wiring 28 is electrically connected to the transparent electrode 45 and forms an auxiliary capacity.

  A SiNx (silicon nitride) gate insulating film 30 is disposed on the glass substrate 25 on which the gate wiring 26, the gate electrode 27, the auxiliary capacitance wiring 28 and the auxiliary capacitance electrode 29 are arranged so as to cover the entire surface of the glass substrate 25. Is done. Further, an amorphous Si (silicon) semiconductor layer 31 is disposed in a region where the TFT 36 is formed and on the gate insulating film 30. A semiconductor contact layer 32 that is a diffusion region of the TFT 36 is disposed on the semiconductor layer 31. Here, the semiconductor contact layer 32 includes semiconductor contact layers 32a and 32b. The semiconductor contact layer 32a is formed of n + type amorphous silicon doped with P (phosphorus) and serves as a source. The semiconductor contact layer 32b is formed of n + type amorphous silicon doped with P (phosphorus) in a state of being separated from the semiconductor contact layer 32a, and serves as a drain.

  The source electrode 34 is formed of a light-shielding conductive material (for example, Mo (molybdenum)) on the semiconductor contact layer 32a. The drain electrode 35 is formed of a light shielding conductive material (for example, Mo) on the semiconductor contact layer 32b. Further, as shown in FIG. 4, a source wiring 33 electrically connected to the TFT 36 (specifically, the source electrode 34) is disposed in a predetermined region above the gate insulating film 30. Further, a SiN protective film 37 is disposed on the gate insulating film 30, the source wiring 33, the source electrode 34 and the drain electrode 35. A drain contact hole 37 a is formed in a predetermined region of the protective film 37. Thereby, a part of the drain electrode 35 is exposed from the protective film 37.

  The interlayer insulating film 38 is formed of an organic resin and constitutes a part of the active matrix substrate 22. The interlayer insulating film 38 is disposed on the protective film 37 so as to cover the protective film 37. The main surface of the interlayer insulating film 38 has a flat shape in the transmissive region T and an uneven shape in the reflective region R. Since the main surface of the interlayer insulating film 38 has such a shape, the main surface of the active matrix substrate 22 (hereinafter referred to as the active matrix substrate 22) in the vicinity of the boundary between the flat shape of the transmission region T and the uneven shape of the reflection region R. The main surface indicates a surface in contact with the liquid crystal layer 24.) The portions whose shapes change discontinuously (that is, the boundary portions 38a to 38d) are generated. In addition, the part (namely, boundary part 38a-38d) in which the said main surface shape changes discontinuously forms the tetragon | quadrangle as shown as a continuous line in the outer edge vicinity of the reflective area | region R in FIG. In FIG. 2 and FIG. 2, the part where the main surface shape changes discontinuously is indicated by a solid line, and the other part is indicated by a dotted line. When light passes through the boundary portions 38a to 38d, the contrast of the reflection / transmission type liquid crystal display device is lowered. Therefore, in the reflection / transmission liquid crystal display device according to the present embodiment, a light-shielding portion is provided so that light does not pass through this portion. The details of the light shielding portion will be described later.

  In addition, a drain contact hole 38e penetrating the interlayer insulating film 38 is opened above the region where the drain contact hole 37a is formed.

  Further, a transparent electrode 39 is disposed on the interlayer insulating film 38 in a state of following the main surface shape of the interlayer insulating film 38. The transparent electrode 39 transmits light and plays a role of changing the alignment of liquid crystal molecules of the liquid crystal layer 24 by generating an electric field when a voltage is applied. The transparent electrode 39 is made of a light-transmitting conductive material (for example, ITO (In-Sn-O). Note that the transparent electrode 39 is a pixel region as shown by a solid line portion in FIGS. 1 and 2. 4 have end portions 39a to 39d, which are portions where the shape of the main surface of the active matrix substrate 22 changes discontinuously (specifically, FIG. 3). Therefore, when the light passes through such a portion, the contrast of the reflection / transmission liquid crystal display device is reduced, so that the reflection / transmission according to this embodiment is performed. In the dual-use liquid crystal display device, a light-shielding portion is provided so that light does not pass through the portion, and details of the light-shielding portion will be described later.

  As shown in FIG. 3, the reflective region R and the upper layer of the transparent electrode 39 have a conductive reflective material (for example, in a state following the main surface shape of the transparent electrode 39 (that is, the interlayer insulating film 38)). , Al / Mo), the film-like reflective electrode 40 is arranged. The reflective electrode 40 constitutes a part of the active matrix substrate 22 and reflects light incident on the liquid crystal layer 24 from the counter substrate 23 side to the counter substrate 23 side. Note that the reflection / transmission liquid crystal display device according to the present embodiment has a structure in which the directivity of reflected light is reduced (regular reflection is reduced) in order to obtain white light that is easy to see like paper. Specifically, as shown in FIG. 3, unevenness is formed on the reflective electrode 40 in the reflective region R of the reflective / transmissive liquid crystal display device. Thereby, the light reflected in the reflective electrode 40 is scattered. As a result, it is possible to obtain white light that is easy to see like paper in the conventional reflective / transmissive liquid crystal display device 21.

Further, as shown in FIGS. 1 and 2, the reflective electrode 40 has end portions 40 a to 40 d in the vicinity of the outer edge of the reflective region R. Such end portions 40a to 40d are portions in which the main surface shape of the active matrix substrate 38 changes discontinuously (specifically, refer to the end portions 40a and 40c in FIG. 3). That is, when light passes through such a portion, the contrast of the reflection / transmission liquid crystal display device is lowered. Therefore, in the reflection / transmission liquid crystal display device according to the present embodiment, a light shielding portion is provided so that light does not pass through such a portion. The details of the light shielding portion will be described later. This is the end of the description of the active matrix substrate 22.
(Regarding the structure of the counter substrate 23)
Next, details of the counter substrate 23 will be described mainly with reference to FIG. For convenience of explanation, the counter substrate 23 will be described in order from the upper layer side to the lower layer side in FIG.

  A colored layer 43 is disposed on the main surface of the glass substrate 42. The colored layer 43 serves as a color filter and constitutes a part of the counter substrate 23. In a predetermined region on the main surface of the glass substrate 42 on which the colored layer 43 is formed, a convex portion 44 that protrudes in a direction perpendicular to the main surface of the glass substrate 42 is provided. The convex portion 44 is made of an insulating material made of an organic resin such as an acrylic resin and is transparent. Below, the said convex part 44 is demonstrated in detail.

  The convex portion 44 is formed on the main surface of the counter substrate 23 so that the layer thickness of the liquid crystal layer 24 in the reflection region R is smaller than the layer thickness of the liquid crystal layer 24 in the transmission region T. Specifically, the convex portion 44 makes the thickness of the liquid crystal layer 24 in the reflection region R approximately ½ of the thickness of the liquid crystal layer 24 in the transmission region T. Thereby, the optical path length of the light output from the backlight in the transmission region T in the liquid crystal layer 24 and the optical path length of the light reflected by the reflective electrode 40 in the reflection region R are made equal.

  Here, when the convex portion 44 is provided, a step is generated at the end of the convex portion 44 as shown in FIG. Such a step is a portion where the shape of the main surface of the counter substrate 23 (hereinafter, the main surface of the counter substrate 23 is a surface in contact with the liquid crystal layer 24) changes discontinuously. When light passes through such a portion, the contrast of the reflective / transmissive liquid crystal display device is lowered. Moreover, as shown in FIG. 3, the side walls 44a and 44b exist in the level | step difference. Such side walls 44a and 44b have a rectangular shape that is long in the horizontal direction as shown in FIG. 2 (in FIG. 2, only the portion extending in the horizontal direction in FIG. 2 is shown, and the vertical direction in FIG. The portion extending to is not shown). The side walls 44 a and 44 b change the layer thickness of the liquid crystal layer 24. Therefore, when light passes through the side walls 44a and 44b, the contrast of the reflection / transmission liquid crystal display device 21 is lowered. Therefore, in the reflection / transmission liquid crystal display device 21 according to the present embodiment, a light-shielding portion is provided so that light does not pass through the side walls 44 a and 44 b of the convex portion 44. The details of the light shielding portion will be described later.

A transparent electrode 45 is disposed on the main surface of the colored layer 43 and the convex portion 44. The transparent electrode 45 transmits light and plays a role of changing the alignment of the liquid crystal molecules of the liquid crystal layer 24 by generating an electric field when a voltage is applied. The transparent electrode 45 is made of a light-transmitting conductive material (for example, ITO (In-Sn-O). This is the end of the description of the counter substrate 23. Note that the active matrix substrate 22 described above is also used. And the counter substrate 23 are arranged so as to sandwich the liquid crystal layer 24 therebetween.
(About shading part)
Next, the light shielding part of the liquid crystal display device 21 according to the present embodiment will be described in detail. In the light shielding portion of the liquid crystal display device according to the present embodiment, light incident on the liquid crystal layer 24 from the active matrix substrate 22 side passes through the portion where the main surface shape changes discontinuously and is transmitted to the counter substrate 23 side. Is to prevent. In the present embodiment, a wiring formed on the main surface of the active matrix substrate 22 is used as the light shielding portion. Specifically, the gate wiring 26, the auxiliary capacitance wiring 28, and the source wiring 33 serve as a light shielding portion. In the following, the light-shielding portion (gate wiring 26, auxiliary capacitance wiring 28, and source wiring 33) according to the present embodiment, and portions where the main surface shape changes discontinuously (boundary portions 38a to 38d, end portions 39a to 39d, end portions The positional relationship between the portions 40a to 40d and the steps (side walls 44a and 44b) will be described, and Fig. 5 is an enlarged view of the elliptical portion (A) in Figs. Fig. 7 is an enlarged view of the elliptical portion (B) of Fig. 2. Fig. 7 is an enlarged view of the elliptical portion (C) of Fig. 1 and Fig. 2. Fig. 8 is an elliptical portion (D) of Fig. 1 and Fig. 2. Fig. 9 is an enlarged view of the oval portion (E) of Figs.

  The gate wiring 26, the auxiliary capacitance wiring 28, and the source wiring 33 are provided in a portion where the main surface shape changes discontinuously. Specifically, as shown in FIGS. 1 and 2, when the main surface of the active matrix substrate 22 is viewed from above, the gate wiring 26 includes a boundary portion 38 a between the uneven portion and the flat portion, and the transparent electrode 39. The end portions 39a and 39c, the end portion 40a of the reflective electrode 40, the step and the side wall 44a of the step are disposed directly below. That is, as shown in FIG. 5, the end portion 40a of the reflective electrode 40 is located at a position that overlaps with the gate wiring 26 and is 1 μm away from the long side of the gate wiring 26 on the center side of the pixel region. To do. Further, as shown in FIG. 5, the boundary portion 38a and the side wall 44a between the concavo-convex portion and the flat portion are positions overlapping the gate wiring 26 and 2 μm from the long side on the center side of the pixel region of the gate wiring 26. It exists only in the position away. As shown in FIG. 5, the end portion 39 a of the transparent electrode 39 is located at a position overlapping the gate wiring 26 and at a position 3 μm away from the long side on the center side of the pixel area of the gate wiring 26. Further, as shown in FIG. 7, the end portion 39 c of the transparent electrode 39 is a position overlapping the gate wiring 26 provided on the transmission region T side, and the long side on the center side of the pixel region of the gate wiring 26. Exists at a position 3 μm away from the center.

  Further, the source wiring 33 has a boundary portion 38b between the uneven portion and the flat portion, a boundary portion 38d between the uneven portion and the flat portion, and an end portion of the transparent electrode 39 when the main surface of the active matrix substrate 22 is viewed from above. 39b, an end 39d of the transparent electrode 39, an end 40b of the reflective electrode 40, and an end 40d of the reflective electrode 40. Specifically, as shown in FIG. 6, the end portion 40 b of the reflective electrode 40 is a position that overlaps the source wiring 33 and is separated by 1 μm from the long side on the center side of the pixel region of the source wiring 33. Exists in position. Further, as shown in FIG. 6, the boundary portion 38 b between the concavo-convex portion and the flat portion is a position overlapping the source wiring 33, and is separated by 2 μm from the long side on the center side of the pixel region of the source wiring 33. Exists in position. Further, as shown in FIG. 6, the end portion 39 b of the transparent electrode 39 is located at a position overlapping the source wiring 33 and at a position 3 μm away from the long side on the center side of the pixel region of the source wiring 33. . Further, as shown in FIG. 8, the end portion 40 d of the reflective electrode 40 is located at a position overlapping the source wiring 33 and at a position separated by 1 μm from the long side on the center side of the pixel region of the source wiring 33. . Further, as shown in FIG. 8, the boundary portion 38d between the uneven portion 38f and the flat portion 38g is a position overlapping the source wiring 33, and is only 2 μm from the edge of the source wiring 33 on the center side of the pixel region. It exists in a distant position. Further, as shown in FIG. 8, the end portion 39 d of the transparent electrode 39 is located at a position overlapping the source wiring 33 and at a position 3 μm away from the long side of the source wiring 33 on the center side of the pixel region. To do.

  Further, as shown in FIGS. 1 and 2, the auxiliary capacitance wiring 28 has a boundary portion 38c between the uneven portion 38f and the flat portion 38g and the reflection electrode 40 when the main surface of the active matrix substrate 22 is viewed from above. The end portion 40 c and the side wall 44 b of the convex portion 44 are disposed directly below. Specifically, as shown in FIG. 9, the boundary portion 38c and the side wall 44b between the uneven portion 38f and the flat portion 38g are positions overlapping the auxiliary capacitance wiring 28 and on the transmission region T side of the auxiliary capacitance wiring 28. It exists at a position 2 μm away from the edge. Further, the end portion 40 c of the reflective electrode 40 is located at a position overlapping the auxiliary capacitance line 28 and at a position 3 μm away from the edge of the auxiliary capacitance line 28 on the transmission region T side.

  When the positional relationship as described above is established, the area of the reflective electrode 40 is smaller than the uneven portion 38f. Further, the entire periphery of the outer edges of the end portions 40a to 40d of the reflective electrode 40 is disposed within the uneven portion 38f, that is, the reflective electrode 40 is included in the uneven portion 38f.

  In addition, the area of the transparent electrode 39 is larger than the uneven portion 38f. Further, the entire periphery of the outer edge of the concavo-convex portion 38 f is disposed within the transparent electrode 39, that is, the concavo-convex portion 38 f is included in the transparent electrode 39. As described above, the transparent electrode 39 extends beyond the uneven portion 38f to the flat portion 38g, so that the patterning property is improved and the transparent electrode 39 is hardly peeled off. This is the end of the description of the light shielding unit.

  As described above, according to the reflection / transmission liquid crystal display device according to the present embodiment, it is possible to prevent light passing through a portion where the main surface shape changes discontinuously. As a result, in the reflection / transmission liquid crystal display device of the present invention, the contrast characteristics are improved as compared with the conventional reflection / transmission liquid crystal display device.

  Further, the reflection / transmission liquid crystal display device according to the present embodiment reflects light incident from the outside in the device to display an image and light generated in the backlight in the device, And a transmissive region T for displaying an image through the liquid crystal layer. Such a reflection / transmission liquid crystal display device according to this embodiment can display an image using the reflection region R and the transmission region T indoors and can display an image using only the reflection region R outdoors. As a result, the reflective / transmissive liquid crystal display device according to the present embodiment can obtain a bright display both indoors and outdoors. Further, when the reflection / transmission liquid crystal display device is used outdoors, the backlight is not used, so that power consumption can be reduced.

  In the present embodiment, the gate wiring 26, the source wiring 33, and the auxiliary capacitance wiring 28 are used as a light shielding portion in order to prevent light from being transmitted through a portion where the main surface shape changes discontinuously. The thing used as a light-shielding part is not restricted to this. As the light shielding portion, for example, the gate electrode 27, the source electrode 34, the auxiliary capacitance electrode 35, or the like may be used.

In the present embodiment, the convex portion 44 is formed on the counter substrate 23, but the convex portion 44 may be formed on the active matrix substrate 22 side.
(About manufacturing method)
Finally, the manufacturing method of the liquid crystal display device according to the present embodiment will be described with reference to FIGS.

  First, a method for manufacturing the active matrix substrate 22 will be described. First, a conductive thin film made of Ta is formed on the glass substrate 25 with a film thickness of 200 nm. Next, the conductive thin film is patterned by using a photolithography technique to form the gate wiring 26, the gate electrode 27, the auxiliary capacitance wiring 28, and the auxiliary capacitance electrode 29. Here, the line width of the gate wiring 26 is 15 μm. The auxiliary capacitor wiring 28 has a line width of 10 μm. The glass substrate 25 may be other transparent insulating material. As for the gate material and the like, other conductive materials such as Al (aluminum), Cr (chromium), Mo (molybdenum), W (tungsten), Cu (steel), and Ti (titanium) may be used. The gate material or the like may be a laminated film made of a plurality of types of materials.

  Next, a SiNx thin film having a thickness of 400 nm is formed as the gate insulating film 30 by a CVD (Chemical Vapor Deposition) method. Next, a thin film of amorphous Si having a thickness of 100 nm is formed as the semiconductor layer 31 by the CVD method. Next, a thin film with a thickness of 40 nm of n + type amorphous Si doped with P is formed by the CVD method as the semiconductor contact layer 32. Thereafter, a patterning process using a photolithography technique is performed to form a semiconductor layer 31 and semiconductor contact layers 32a and 32b each having a predetermined shape.

  Next, a 150 nm thick conductive film made of Mo is formed. Thereafter, the conductive film is patterned using a photolithography technique to form the source wiring 33, the source electrode 34, and the drain electrode 35. Here, the line width of the source wiring 33 is 15 μm. In this embodiment, Mo is used as the conductive film, but other conductive materials such as Al, Cr, Ta, W, Cu, and Ti may be used. The conductive film may be a laminated film made of a plurality of types of materials.

  Next, a part of the semiconductor contact layer 32 is removed by etching using the source electrode 34 and the drain electrode 35 as a mask. Thereby, the semiconductor contact layer 32 is separated into the semiconductor contact layer 32a on the source side and the semiconductor contact layer 32b on the drain side, and the TFT 36 is formed.

  Next, a thin film of SiN having a thickness of 200 nm is formed as the protective film 37. Thereafter, a photolithography technique is applied to remove a predetermined portion of the protective film 37 to form a drain contact hole 37a.

  Next, an organic resin film having a thickness of 3000 nm is formed as an interlayer insulating film 38. Thereafter, an unnecessary portion of the interlayer insulating film 38 such as the drain contact hole 38e is removed by applying a photolithography technique. At this time, an uneven portion 38f for scattering incident light from the outside is formed in a portion of the interlayer insulating film 38 where the reflective electrode 40 to be a reflective layer is to be formed. The height of the uneven portion 38f is 1000 nm. In this embodiment, an organic resin film is used as the interlayer insulating film 38, but the interlayer insulating film 38 may be a laminated film made of a plurality of types of materials.

  Next, a 100 nm-thick transparent conductive film such as ITO is formed. Thereafter, the transparent conductive film is patterned using a photolithography technique to form the transparent electrode 39. In this embodiment, ITO (In—Sn—O) is used for the transparent electrode 39, but another material having conductivity such as IZO (In—Zn—O) is used for the transparent electrode 39. May be. The material may be a laminated film made of a plurality of types of materials.

  Next, a conductive reflective material is formed on the upper surface of the transparent electrode 39. Thereafter, the reflective material 40 is patterned by photolithography to form the reflective electrode 40. As the reflective electrode 40, a laminated film of Al / Mo is used. Specifically, an Al thin film with a thickness of 100 nm and a Mo thin film with a thickness of 50 nm are used. In addition, as the reflective electrode 40, other conductive materials such as Al and Ag may be used, or a reflective material having no electrical conductivity may be used. The active matrix substrate 22 of this embodiment is completed through the above steps.

  Next, a method for manufacturing the counter substrate 23 will be described. First, a colored layer 43 to be a color filter is formed on the glass substrate 42. Next, an insulating film made of an organic resin film such as an acrylic resin is formed as a convex portion 44 at a predetermined position of the colored layer 43. The convex portion 44 is transparent. The glass substrate 42 may be a transparent insulating material other than glass. In this embodiment, an organic resin film is used for the convex portion 44, but the material of the convex portion 44 is not limited to this. Further, the convex portion 44 may be a laminated film made of a plurality of types of transparent materials.

  Next, a transparent conductive film having a thickness of 100 nm is formed as a transparent electrode 45 using ITO or the like. In this embodiment, ITO (In—Sn—O) is used for the transparent conductive film, but other transparent materials having conductivity such as IZO (In—Zn—O) may be used. Good. The transparent conductive film may be a laminated film made of a plurality of types of materials. The counter substrate 23 of this embodiment is completed through the above steps.

Finally, the active matrix substrate 22 and the counter substrate 23 are bonded via the liquid crystal layer 24 so that the convex portion 44 faces the reflective electrode 40. The reflection / transmission liquid crystal display device 21 according to the present embodiment is completed through the above steps.
(Second Embodiment)
Hereinafter, a display device referred to as a reflection / transmission type station writing according to a second embodiment of the present invention will be described with reference to the drawings. 10 and 11 are views showing a reflection / transmission liquid crystal display device according to a second embodiment of the present invention. Specifically, FIG. 10 is a view of the active matrix substrate 22 as viewed from above in a state where the counter substrate 48 is bonded to the active matrix substrate 22. 11 is a cross-sectional view taken along the line II of FIG. In the reflection / transmission liquid crystal display device according to this embodiment, the counter substrate 48 is provided with a black mask 47 serving as a light shielding mask.

  In the counter substrate 48, a colored layer 43 serving as a color filter is disposed on the main surface of the glass substrate 42, and a black mask 47 is formed in the same layer as the colored layer 43. The black mask 47 includes side walls 44a and 44b of the convex portion 44, end portions 39a to 39d of the transparent electrode 39, end portions 40a to 40d of the reflective electrode 40, and a boundary portion between the flat portion 38g and the uneven portion 38f of the interlayer insulating film 38. It is arrange | positioned just above 38a-38d. That is, as represented by the hatched portion in FIG. 10, the black mask 47 is formed in a matrix in plan view.

With the above configuration, discontinuously changing portions that cause liquid crystal alignment disturbance and optical path length disturbance (the side walls 44a and 44b of the convex portion 44, the end portions 39a to 39d of the transparent electrode 39, and the end portions 40a to 40d of the reflective electrode 40). Further, the boundary portions 38a to 38d) between the flat portion 38g and the concavo-convex portion 38f can be surely hidden by the black mask 47, and the contrast characteristics can be improved. Note that the black mask 47 does not necessarily have to be formed in a matrix as shown in FIG. 10, and may be partially formed on a portion where light shielding is desired. Other configurations are the same as those in the first embodiment, and thus the same reference numerals are given and description thereof is omitted.
(Third embodiment)
Hereinafter, a reflective / transmissive liquid crystal display device according to a third embodiment of the present invention will be described with reference to the drawings. FIG. 12 is a view showing a reflection / transmission liquid crystal display device according to a third embodiment of the present invention. In the reflection / transmission liquid crystal display device according to this embodiment, the end portions of the different colored layers 50 and 51 adjacent to each other on the counter substrate 53 are intentionally overlapped, and the color overlap black mask 52 which is substantially blackened by the mixed color is provided. The light shielding mask is formed. Specifically, the opposing substrate 53 is provided with colored layers 50 and 51 serving as color filters on the main surface of the glass substrate 42, and the colored layers 50 and 51 between adjacent picture elements have different colors. ing. For example, the color of the colored layer 50 and the color of the colored layer 51 are selected from R (red), G (green), and B (blue). The end portions of the colored layer 50 and the colored layer 51 are overlapped and overlapped to form a color overlap black mask 52 that is substantially blackened by increasing color density due to color mixture and increasing layer thickness.

  The color overlapping black mask 52 is formed immediately above the side wall 44a of the convex portion 44, the end portion 39a of the transparent electrode 39, the end portion 40a of the reflective electrode 40, and the boundary portion 38a between the flat portion 38g and the uneven portion 38f of the interlayer insulating film 38. Has been placed. Although not shown in the figure, the end portions 39b to 39d of the transparent electrode 39, the end portions 40b and 40d of the reflective electrode 40, the flat portion 38g and the concavo-convex portion of the interlayer insulating film 38 are similarly formed at the boundary between other picture elements. It is preferable that the boundary portions 38b and 38d with respect to 38f are concealed by the color overlap black mask 52.

  A black mask 47 is formed in the same layer as the colored layers 50 and 51. The black mask 47 is disposed immediately above the side wall 44b of the convex portion 44, the end portion 40c of the reflective electrode 40, and the boundary portion 38c between the flat portion 38g and the concave-convex portion 38f of the interlayer insulating film 38. That is, the black mask 47 is formed at a position where different colored layers cannot be overlapped, such as a boundary portion between the transmission region T and the reflection region R.

With the above configuration, discontinuously changing portions that cause liquid crystal alignment disturbance and optical path length disturbance (side walls 44a and 44b of the convex portion 44, end portions 39a to 39d of the transparent electrode 39, end portions 40a to 40d of the reflective electrode 40, and The boundary portions 38a to 38d) between the flat portion 38g and the concavo-convex portion 38f of the interlayer insulating film 38 can be concealed and shaded by the color overlap black mask 52 and the black mask 47, and the contrast characteristics can be improved. Since other configurations are the same as those of the first embodiment, the same reference numerals are given and description thereof is omitted.
(Fourth embodiment)
The reflection / transmission liquid crystal display device according to the fourth embodiment of the present invention will be described below with reference to FIG. FIG. 13 is a bottom view showing a reflective / transmissive liquid crystal display device according to a fourth embodiment of the present invention. The difference between the reflection / transmission liquid crystal display device according to the present embodiment and the reflection / transmission liquid crystal display device according to the first embodiment is that the convex portion 144 on the counter substrate side providing the multi-gap structure is seen in a plan view. In this case, each pixel is formed in a quadrangular shape.

  Among the four side walls 144a to 144d of the convex portion 144, the side walls 144b and 144d parallel to the source wiring 33 are positions overlapping the source wiring 33 as shown in FIG. It exists at a position 2 μm away from the edge on the center side.

As in the first embodiment, the side wall 144a overlaps with the gate wiring 26 and exists at a position 2 μm away from the edge of the gate wiring 26 on the center side of the pixel region. As in the first embodiment, the side wall 144c overlaps the auxiliary capacitance line 28 and exists at a position 2 μm away from the edge of the auxiliary capacitance line 28 on the transmission region T side. Since other configurations are the same as those of the first embodiment, the same reference numerals are given and description thereof is omitted. In the present embodiment, it is needless to say that a light shielding structure using a black mask or a color overlay black mask may be adopted as in the second and third embodiments.
(Fifth embodiment)
Hereinafter, a reflective / transmissive liquid crystal display device according to a fifth embodiment of the present invention will be described with reference to the drawings. 14 to 21 are diagrams showing a reflection / transmission liquid crystal display device according to a fifth embodiment. Specifically, FIG. 14 is a view when the active matrix substrate 61 is viewed from the upper side perpendicular to the main surface. 15 is a cross-sectional view taken along the line II in FIG. 16 is a cross-sectional view taken along the line II-II in FIG. In addition, the same code | symbol is attached | subjected to the structure same as 1st Embodiment.

In the reflection / transmission liquid crystal display device 60 according to the present embodiment, a convex portion 64 providing a multi-gap structure is provided on the active matrix substrate 61 side. The active matrix substrate 61 includes a glass substrate 25, a gate wiring 26, an auxiliary capacitance wiring 28, a gate insulating film 30, a source wiring 33, a TFT 36, a protective film 37, an interlayer insulating film 64, a transparent electrode 65, and a reflective electrode 66. The counter substrate 62 includes a glass substrate 42, a colored layer 43, and a transparent electrode 67.
(About the structure of the active matrix substrate 61)
In the active matrix substrate 61, a glass substrate 25, a gate wiring 26, an auxiliary capacitance wiring 28, a gate insulating film 30, a source wiring 33, a TFT 36, and a protective film 37 are formed in order from the lower layer. The configuration of the active matrix substrate 61 is the same as that of the active matrix substrate 22 of the first embodiment. The interlayer insulating film 64 is formed on an upper layer of the protective film 37 with an organic resin and constitutes a part of the active matrix substrate 61. The interlayer insulating film 64 is formed at least in the reflective region R but not in the transmissive region T. Thus, the interlayer insulating film 64 also serves as the convex portion 64 so that the layer thickness of the liquid crystal layer 63 in the reflection region R is smaller than the layer thickness of the liquid crystal layer 63 in the transmission region T (hereinafter, 64 is an interlayer) This will be referred to as an insulating film or a convex portion). Specifically, the convex portion 64 makes the thickness of the liquid crystal layer 63 in the reflective region R approximately half the thickness of the liquid crystal layer 63 in the transmissive region T. Thereby, the optical path length of the light output from the backlight in the transmission region T in the liquid crystal layer 63 and the optical path length of the light reflected by the reflective electrode 66 in the reflection region R are substantially the same. That is, in the transmissive region T without the protrusion 64, the transmissive region opening H is formed to provide a multi-gap structure. A drain contact hole 64e penetrating the interlayer insulating film 64 is opened above the region where the drain contact hole 37a is formed.

  On the main surface of the interlayer insulating film 64, an uneven portion 64f is formed in the reflective region R, and the other portion is a flat portion 64g. Therefore, discontinuously changing portions of the main surface of the active matrix substrate 61 (that is, the boundary portions 64a to 64d and 64l to 64p) are generated at the boundary between the flat portion 64g and the uneven portion 64f of the interlayer insulating film 64. The boundary portions 64a to 64d form a rectangle as shown by a solid line in the vicinity of the outer edge of the picture element region in FIG. The boundary portions 64l to 64p form a substantially square shape as indicated by a solid line in the vicinity of the outer edge of the transmission region T in FIG. When light passes through these discontinuously changing portions, the contrast of the liquid crystal display device 60 is reduced. Therefore, in the liquid crystal display device 60 according to the present embodiment, a light shielding portion is provided so that light does not pass through the boundary portions 64a to 64d and 64l to 64p. The details of the light shielding portion will be described later.

  Further, side walls 64 h to 64 k are formed in the convex portion (interlayer insulating film) 64 so as to surround the transmission region opening H. The side walls 64h to 64k cause a discontinuous change portion on the main surface of the active matrix substrate 61 (specifically, refer to the side wall 64h in FIG. 15). The side walls 64h to 64k are inclined for manufacturing reasons, and the layer thickness of the liquid crystal layer 63 is continuously changed. Therefore, when light passes through the side walls 64h to 64k, the contrast of the liquid crystal display device 60 is lowered. Therefore, in the liquid crystal display device 60 according to the present embodiment, a light shielding portion is provided so that light does not pass through the side walls 64h to 64k. The details of the light shielding portion will be described later.

  The transparent electrode 65 is disposed in a state of following the shape of the main surface so as to continuously cover the protective film 37 in the transmissive region T and the interlayer insulating film 64 in the reflective region R. The transparent electrode 65 has four end portions 65a to 65d in the vicinity of the outer edge of the picture element region, as shown by the solid line portion in FIG. Such end portions 65a to 65d are portions where the main surface shape of the active matrix substrate 61 changes discontinuously. (Specifically, see the end portion 65a in FIG. 15 and the end portion 65b in FIG. 16). As light passes through the stepped portion, the contrast of the liquid crystal display device 60 is lowered. Therefore, in the liquid crystal display device 60 according to the present embodiment, a light blocking portion is provided so that light does not pass through the end portions 65a to 65d. The details of the light shielding portion will be described later.

  As shown in FIG. 15, a conductive reflective material (for example, Al / Mo) is formed on the upper layer of the transparent electrode 65 in the reflective region R in a state following the main surface shape of the transparent electrode 65 (that is, the interlayer insulating film 64). Thus, a reflective electrode (reflective film) 66 is disposed. As shown in FIG. 14, the reflective electrode 66 has rectangular outer end portions 66a to 66d in the vicinity of the outer edge of the picture element region, and has square inner end portions 66e to 66h in the vicinity of the outer edge of the transmissive region T. is doing. That is, the reflective electrode 66 having the outer edges 66a to 66d on the four sides as outer edges has a shape in which openings formed from the inner ends 66e to 66h on the four sides are formed.

Such outer end portions 66a to 66d and inner end portions 66e to 66h are portions where the main surface shape of the active matrix substrate 61 changes discontinuously (specifically, the outer end portions 66a of FIG. 15). And the inner end 66e and the outer end 66b of FIG. 16). When light passes through these discontinuously changing portions, the contrast of the liquid crystal display device 60 is reduced. Therefore, in the liquid crystal display device 60 according to the present embodiment, a light shielding portion is provided so that light does not pass through the outer end portions 66a to 66d and the inner end portions 66e to 66h. The details of the light shielding portion will be described later.
(Regarding the structure of the counter substrate 62)
In the counter substrate 62, a colored layer 43 serving as a color filter is disposed on the main surface of the glass substrate 42. A transparent electrode 67 is disposed on the main surface of the colored layer 43. The transparent electrode 67 plays a role of transmitting light and changing the alignment of the liquid crystal molecules of the liquid crystal layer 63 by generating an electric field when a voltage is applied. The transparent electrode 67 is made of a light transmissive conductive material (for example, ITO (Indium Tin Oxide)).
(About shading part)
The light-shielding portion of the liquid crystal display device 60 according to the present embodiment is configured so that the light incident on the liquid crystal layer 63 from the active matrix substrate 61 side or the counter substrate 62 side passes through the discontinuously changing portion on the main surface. This prevents light from exiting to the 63 side. In the present embodiment, the gate wiring 26, the auxiliary capacitance wiring 28, and the source wiring 33, which are wirings formed on the main surface of the active matrix substrate 61, serve as a light shielding portion.

  Hereinafter, the light-shielding portion (gate wiring 26, auxiliary capacitance wiring 28, and source wiring 33) according to the present embodiment, and discontinuously changing portions on the main surface (boundaries 64a to 64d and 64l to 64p, side walls 64h to 64k, end portions 65a to 65d, outer end portions 66a to 66d and inner end portions 66e to 66h) will be described. FIG. 17 is an enlarged view of the oval part (A) of FIG. FIG. 18 is an enlarged view of the oval part (B) of FIG. FIG. 19 is an enlarged view of the oval part (C) of FIG. FIG. 20 is an enlarged view of the oval part (D) of FIG. FIG. 21 is an enlarged view of the oval part (E) of FIG.

  The gate wiring 26, the source wiring 33, and the auxiliary capacitance wiring 28 are provided in a portion of the main surface that changes discontinuously. Specifically, as shown in FIG. 14, when the main surface of the active matrix substrate 61 is viewed from above, the gate wiring 26 includes boundary portions 64a and 64c between the uneven portion 64f and the flat portion 64g, and the transparent electrode 65. The end portions 65 a and 65 c of the reflective electrode 66, the outer end portions 66 a and 66 c of the reflective electrode 66, the inner end portion 66 g and the side wall 64 j of the convex portion 64. That is, as shown in FIG. 17, the outer end portion 66a of the reflective electrode 66 is located at a position overlapping with the gate wiring 26 and at a position 1 μm away from the edge of the gate wiring 26 on the center side of the pixel region. To do. As shown in FIG. 17, the boundary portion 64 a is located at a position overlapping the gate wiring 26 and at a position 2 μm away from the edge of the gate wiring 26 on the center side of the pixel region. As shown in FIG. 17, the end portion 65 a of the transparent electrode 65 is located at a position overlapping with the gate wiring 26 and at a position 3 μm away from the edge of the gate wiring 26 on the center side of the pixel region.

  Further, as shown in FIG. 19, the side wall 64j and the boundary portion 64n are located at a position overlapping the gate wiring 26 and at a position separated by 1 μm from the edge of the gate wiring 26 on the center side of the pixel region. As shown in FIG. 19, the inner end portion 66 g of the reflective electrode 66 is located at a position overlapping the gate wiring 26 and at a position 2 μm away from the edge of the gate wiring 26 on the center side of the pixel region. As shown in FIG. 19, the outer end portion 66 c of the reflective electrode 66 is located at a position overlapping with the gate wiring 26 and at a position 3 μm away from the edge of the gate wiring 26 on the center side of the pixel region. As shown in FIG. 19, the boundary portion 64 c is located at a position overlapping the gate wiring 26 and at a position separated by 4 μm from the edge of the gate wiring 26 on the center side of the pixel region. As shown in FIG. 19, the end portion 65 c of the transparent electrode 65 is located at a position overlapping the gate wiring 26 and at a position 5 μm away from the edge of the gate wiring 26 on the center side of the pixel region.

  Next, as shown in FIG. 14, when the main surface of the active matrix substrate 61 is viewed from above, the source wiring 33 has boundary portions 64b, 64d, 64m and 64p between the concave and convex portions 64f and the flat portion 64g, transparent, The ends 65 b and 65 d of the electrode 65, the outer ends 66 b and 66 d and the inner ends 66 f and 66 h of the reflective electrode 66, and the side walls 64 i and 64 k of the convex portion 64 are disposed immediately below. Specifically, as shown in FIGS. 18 and 20, the end portions 64 m and 64 p and the side walls 64 i and 64 k overlap with the source wiring 33, and are the edge on the center side of the pixel region of the source wiring 33. 1 μm away from the center. Further, as shown in FIGS. 18 and 20, the inner end portions 66f and 66h of the reflective electrode 66 overlap with the source wiring 33 and are 2 μm from the edge of the source wiring 33 on the center side of the pixel region. It exists in a distant position. Further, as shown in FIGS. 18 and 20, the outer end portions 66b and 66d of the reflective electrode 66 are positions that overlap with the source wiring 33 and are 3 μm from the edge of the source wiring 33 on the center side of the pixel region. It exists in a distant position. Further, as shown in FIGS. 18 and 20, the boundary portions 64b and 64d exist at positions that overlap with the source wiring 33 and are separated by 4 μm from the edge of the source wiring 33 on the center side of the pixel region. To do. Further, as shown in FIGS. 18 and 20, the end portions 65 b and 65 d of the transparent electrode 65 are positions where they overlap with the source wiring 33, and are separated by 5 μm from the edge on the center side of the pixel region of the source wiring 33. Exists in the position.

  Further, as shown in FIG. 14, the auxiliary capacitance wiring 28 has a boundary portion 64l between the uneven portion 64f and the flat portion 64g and the inner end portion of the reflective electrode 64 when the main surface of the active matrix substrate 61 is viewed from above. 66e and the side wall 64h of the convex portion 64. Specifically, the boundary portion 64l and the side wall 64h between the concave and convex portion 64f and the flat portion 64g are positions where the auxiliary capacitance wiring 28 overlaps with each other on the transmission region T side of the auxiliary capacitance wiring 28 as shown in FIG. It exists at a position 1 μm away from the edge. The end 66e of the reflective electrode 66 is located at a position that overlaps the auxiliary capacitance line 28 and is separated by 2 μm from the edge of the auxiliary capacitance line 28 on the transmission region T side.

  When the positional relationship as described above is established, the area of the reflective electrode 66 is smaller than that of the concave and convex portion 64f, and the reflective electrode 66 is disposed within the concave and convex portion 64f. That is, the reflective electrode 66 is disposed so as to be covered by the uneven portion 64f. In this case, the outer end portions 66a to 66d and the inner end portions 66e to 66h of the reflective electrode 66 are not placed on the flat portion 64g, so that no stepped portion is generated in the flat portion 64g and the alignment disorder of the liquid crystal layer 63 is suppressed. Can do.

As described above, according to the reflection / transmission liquid crystal display device 60 according to the present embodiment, light passing through a portion where the main surface shape changes discontinuously is shielded from being viewed from the observer side. Therefore, the contrast characteristic is improved as compared with the conventional reflective / transmissive liquid crystal display device.
(About manufacturing method)
A method for manufacturing the liquid crystal display device 60 according to the present embodiment will be described with reference to FIGS.

  First, a method for manufacturing the active matrix substrate 22 will be described. The manufacturing procedure from the lower layer to the glass substrate 25, the gate wiring 26, the auxiliary capacitance wiring 28, the gate insulating film 30, the source wiring 33, the TFT 36, and the protective film 37 is the same as the manufacturing method in the first embodiment.

  Next, an organic resin film having a thickness of 3000 nm is formed as an interlayer insulating film 64 on the protective film 37. Thereafter, unnecessary portions of the interlayer insulating film 38 such as the transmissive region opening H are removed by using a photolithography technique. That is, by providing the transmissive region opening H, a convex portion 64 that provides a multi-gap structure is formed (hereinafter, 64 is referred to as an interlayer insulating film or a convex portion). At this time, an uneven portion 64f for scattering incident light from the outside is formed in the interlayer insulating film 64 where the reflective electrode 66 is to be formed. The height of the uneven portion 64f is 1000 nm.

  Next, a 100 nm-thick transparent conductive film such as ITO is formed so as to cover the protective film 37 and the convex portions 64. Thereafter, the transparent conductive film is patterned by using a photolithography technique to form the transparent electrode 65.

  Next, a conductive reflective material such as Al / Mo is formed on the upper surface of the transparent electrode 65. Thereafter, the reflective material 66 is patterned by photolithography to form the reflective electrode 66. The active matrix substrate 61 of this embodiment is completed through the above steps.

  Next, a method for manufacturing the counter substrate 62 will be described. The counter substrate 62 is manufactured by forming a colored layer 43 to be a color filter on the glass substrate 42 and forming a transparent conductive film having a thickness of 100 nm as a transparent electrode 45 with ITO or the like.

  Finally, the active matrix substrate 61 and the counter substrate 62 are bonded so as to sandwich the liquid crystal layer 63 therebetween. The reflection / transmission type liquid crystal display device 60 according to the present embodiment is completed through the above steps.

Even in the present embodiment in which the convex portions 64 are provided on the active matrix substrate 61 side, a structure in which light is shielded by using a black mask or / and a color overlapping black mask as in the second and third embodiments may be adopted. It goes without saying that it is good.
In the reflection / transmission liquid crystal display devices according to the first to fifth embodiments, the portion where the main surface shape changes discontinuously changes discontinuously due to processing accuracy in the uneven portion or the flat portion. Excluding parts to be used. That is, the portion where the main surface shape changes discontinuously indicates that which occurs in the vicinity of the outer periphery of the transmission region T or the reflection region R as shown in the first to fifth embodiments.

  The present invention aims to prevent a decrease in contrast caused by liquid crystal alignment disorder and the like, and is useful as a reflection / transmission liquid crystal display device.

1 is a top view of a main part showing an active matrix substrate of a liquid crystal display device according to a first embodiment of the present invention. FIG. 2 is a top view of a main part showing a state in which a counter substrate is bonded to an active matrix substrate of the liquid crystal display device of the first embodiment. Sectional view taken along the line II of FIG. II-II sectional view of FIG. Enlarged view of the oval part (A) in FIGS. 1 and 2 Enlarged view of the ellipse part (B) in FIGS. Enlarged view of the oval part (C) in FIGS. 1 and 2 Enlarged view of the ellipse part (D) in FIGS. 1 and 2 Enlarged view of the ellipse portion (E) in FIGS. Top view of the liquid crystal display device of the second embodiment II sectional view of FIG. Sectional drawing of the liquid crystal display device of 3rd Embodiment The principal part top view of the liquid crystal display device of 4th Embodiment The top view of the principal part of the liquid crystal display device of 5th Embodiment FIG. 14 is a cross-sectional view taken along line II of FIG. II-II sectional view of FIG. Enlarged view of the ellipse part (A) in FIG. Enlarged view of the oval part (B) of FIG. Enlarged view of the oval part (C) of FIG. Enlarged view of the ellipse part (D) in FIG. Enlarged view of the ellipse (E) in FIG. Sectional view of a conventional liquid crystal display device

Explanation of symbols

21, 60 Liquid crystal display device 22 Active matrix substrate 23 Counter substrate 24 Liquid crystal layer 25, 42 Glass substrate 26 Gate wiring 27 Gate electrode 28 Auxiliary capacitance wiring 29 Auxiliary capacitance electrode 30 Gate insulating film 31 Semiconductor layer 32 Semiconductor contact layer 33 Source wiring 34 Source electrode 35 Drain electrode 36 TFT
37 Protective film 38 Interlayer insulating films 38a to 38d, 64a to 64d, 64l to 64p Boundary portion 38f Uneven portion 38g Flat portions 39, 45, 65, 67 Transparent electrodes 39a to 39d, 65a to 65d End portions 40, 66 Reflective electrodes ( Reflective film)
40a-40d End portion 66a-66d Outer end portion 66e-66h Inner end portion 43, 49-51 Colored layer 44, 144 Stepped portion 44a-44d, 64h-64k, 144a-144d Side wall 47 Black mask 52 Color overlap black mask 64 Convex part (interlayer insulating film)
H Transmission area opening R Reflection area T Transmission area

Claims (8)

A first substrate;
A second substrate disposed to face the first substrate;
A liquid crystal layer provided between the first substrate and the second substrate;
The main surface on the liquid crystal layer side of the first substrate and / or the main surface on the liquid crystal layer side of the second substrate includes a portion where the main surface shape changes discontinuously,
A light shielding means for preventing light incident on the liquid crystal layer from the second substrate side from passing through the portion where the main surface shape changes discontinuously and transmitting to the first substrate side; Liquid crystal display device. A plurality of images that are defined in a two-dimensional array on the main surface of the second substrate and that display light by reflecting light incident on the liquid crystal layer from the first substrate side toward the first substrate side. The reflective area of
A plurality of images that are defined in a two-dimensional array on the main surface of the second substrate and display an image by transmitting light incident on the liquid crystal layer from the second substrate side to the first substrate side. The liquid crystal display device according to claim 1, further comprising: a transparent region.   The portion where the main surface shape changes discontinuously is the liquid crystal layer of the first substrate such that the layer thickness of the liquid crystal layer in the reflective region is smaller than the layer thickness of the liquid crystal layer in the transmissive region. The liquid crystal display device according to claim 2, wherein the liquid crystal display device is a step formed on the main surface on the side and / or the main surface on the liquid crystal layer side of the second substrate. The second substrate has a wiring formed of a light shielding material,
4. The liquid crystal display device according to claim 3, wherein the light shielding means is a wiring formed in the vicinity of the step among the wirings formed on the second substrate. The plurality of transmission areas and the plurality of reflection areas constitute a plurality of picture element areas by being adjacent to each other,
5. The liquid crystal display according to claim 4, further comprising a plurality of switching elements provided so as to correspond to each of the picture element regions, wherein the wiring is electrically connected to each of the switching elements. apparatus. The transmissive region and the reflective region constitute one picture element region between adjacent ones,
4. The liquid crystal display device according to claim 3, wherein the light shielding means is a light shielding mask formed in the vicinity of the step and formed on the first substrate or the second substrate with a light shielding material. . The second substrate includes, on the main surface on the liquid crystal layer side, an interlayer insulating film having a flat shape in the transmission region and an uneven shape in the reflection region,
3. The liquid crystal display device according to claim 2, wherein the portion where the main surface shape changes discontinuously is a boundary between a flat shape of the interlayer insulating film and an uneven shape of the interlayer insulating film. A reflective film formed on the main surface on the liquid crystal side of the second substrate;
3. The liquid crystal display device according to claim 2, wherein the portion where the main surface shape changes discontinuously is an end portion of the reflective film on a main surface on the liquid crystal side of the second substrate.

Images