JP2003075812A - Manufacturing method for electro-optical device, and electro-optical device and electronic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture an electro-optical device such as a liquid crystal device capable of surely reducing operation failure caused by a lateral field in an electro-optical material such as a liquid crystal and displaying a high contrast, bright, and high quality picture. SOLUTION: The electro-optical device is provided with pixel electrodes (9a) on a TFT array board (10), and a counter electrode (21) on a counter board (20). The substrate surface of the pixel electrodes on the TFT array board is provided with projecting parts (81, 82) in the area opposing a gap between pixel electrodes adjacent to each other. The manufacturing method therefor comprises a forming process for forming a pattern including wiring, TFTs, or the like on the TFT array board, and a process for forming an interlayer insulating film by a high density plasma CVD on the top side of the projecting parts constructed by the presence of the above pattern in the gap area between pixel electrodes adjacent to each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the technical field of electro-optical devices such as liquid crystal devices, and more particularly, to a pixel in which the polarities of voltages applied to pixel electrodes adjacent to each other in the column direction or the row direction are reversed. A thin film transistor (Th that employs an inversion drive method in which the drive voltage polarity is periodically inverted for each row or pixel column
in Film Transistor: hereinafter appropriately referred to as a technical field of an electro-optical device such as an active matrix driving type liquid crystal device using a TFT) and an electronic apparatus such as a projection display device including such an electro-optical device.

[0002]

BACKGROUND ART Generally, in this type of electro-optical device, in order to prevent deterioration of an electro-optical material due to application of a DC voltage and prevent crosstalk and flicker in a display image, a voltage polarity applied to each pixel electrode is set to a predetermined rule. The inversion drive method of reversing is adopted.

During the display corresponding to the image signal of one frame or field, the pixel electrodes arranged in odd rows are driven by the positive potential with reference to the potential of the counter electrode and are arranged in even rows. The pixel electrodes arranged in even rows are driven in reverse while the corresponding pixel electrodes are driven with a negative potential with reference to the potential of the counter electrode and a display corresponding to the image signal of the next frame or field subsequent thereto is performed. Are driven with a positive potential and pixel electrodes arranged in odd rows are driven with a negative potential (that is, while driving pixel electrodes in the same row with the same polarity potential, the potential polarity is The 1H inversion drive method (inversion at frame or field period) is used as an inversion drive method that is relatively easy to control and enables high-quality image display.

Also, the 1S inversion driving method in which the pixel electrodes in the same column are driven by the potential of the same polarity and the voltage polarity is inverted in each frame in a frame or field cycle is relatively easy to control and of high quality. It is used as an inversion drive system that enables image display.

Furthermore, a dot inversion driving method has been developed in which the polarity of the voltage applied to each pixel electrode is inverted between adjacent pixel electrodes in both the column direction and the row direction.

[0006]

However, like the above-mentioned 1H inversion driving method, 1S inversion driving method, dot inversion driving method, etc., the voltage of pixel electrodes adjacent to each other on the TFT array substrate (that is, 1H inversion driving method). Voltage applied to pixel electrodes adjacent to each other in the column direction in the method, voltage applied to pixel electrodes adjacent to each other in the row direction in the 1S inversion driving method, pixel electrodes adjacent to each other in the row and column directions in the dot inversion driving method The voltage applied to) has the opposite polarity,
There arises a problem that a lateral electric field (that is, an electric field parallel to the substrate surface or an oblique electric field including a component parallel to the substrate surface) is generated between adjacent pixel electrodes. When such a lateral electric field is applied to an electro-optical material which is supposed to be applied with a vertical electric field (that is, an electric field in a direction perpendicular to the substrate surface) between the pixel electrode and the counter electrode facing each other. However, there is a problem in that a malfunction of the electro-optical material such as a defective alignment of the liquid crystal occurs, light leakage occurs in this portion, and the contrast ratio decreases.

On the other hand, it is possible to cover the region where the horizontal electric field is generated with the light shielding film, but this causes a problem that the opening region of the pixel becomes narrower depending on the size of the region where the horizontal electric field is generated. Occurs. In particular, such a lateral electric field increases as the distance between adjacent pixel electrodes decreases due to the miniaturization of the pixel pitch, and these problems become more serious as the definition of electro-optical devices becomes higher. I will end up.

The present invention has been made in view of the above-mentioned problems, and it is possible to surely reduce malfunctions due to a lateral electric field in an electro-optical material such as liquid crystal, and to perform a bright, high-contrast liquid crystal device with high contrast. It is an object of the present invention to provide an electro-optical device manufacturing method capable of manufacturing such electro-optical device, an electro-optical device, and an electronic apparatus such as a projection display device including the electro-optical device.

[0009]

In order to solve the above-mentioned problems, the method of manufacturing an electro-optical device according to the present invention comprises an electro-optical substance sandwiched between a pair of first and second substrates. And a first pixel electrode group for inversion driving at
For being driven in the second cycle complementary to the second cycle
An electro-optical device for manufacturing an electro-optical device in which a plurality of pixel electrodes including the pixel electrode group are planarly arranged on the first substrate, and a counter electrode facing the plurality of pixel electrodes is provided on the second substrate. And a step of forming a pattern including wirings and elements for driving the pixel electrodes on the first substrate, and the pattern in a region that is a gap between adjacent pixel electrodes in plan view. The step of forming an interlayer insulating film on the upper side of the convex portion at least partially constructed by the presence of high density plasma CVD or high frequency bias sputtering, and forming the plurality of pixel electrodes after forming the interlayer insulating film. And a process.

According to the method of manufacturing an electro-optical device of the present invention, the electro-optical device according to the manufacturing has a first pixel electrode group for being inverted and driven in the first period and a complementary pixel in the first period. A plurality of pixel electrodes including a second pixel electrode group for inversion driving in the second cycle of are arranged in a plane on the first substrate, and (i) have opposite polarities at each time during inversion driving. There are both adjacent pixel electrodes driven by the driving voltage of (ii) and (ii) adjacent pixel electrodes driven by the driving voltages of the same polarity at each time during the inversion driving.
Both of these types are, for example, the above-mentioned 1H inversion driving method or 1
There is an electro-optical device such as a matrix drive type liquid crystal device adopting an inversion drive system such as an S inversion drive system. Therefore, a lateral electric field is generated between the pixel electrodes adjacent to each other belonging to different pixel electrode groups (that is, the pixel electrodes adjacent to each other to which a potential of opposite polarity is applied).

In the present invention, in particular, wirings (eg, data lines, scanning lines, capacitance lines, etc.) for driving pixel electrodes and elements (eg, T for pixel switching) are provided on the first substrate.
Pattern including FT). Due to the presence of this pattern, a convex portion is at least partially formed in a region which becomes a gap between the pixel electrodes adjacent to each other when seen in a plan view. That is, at least a part of the protrusion is formed directly on the surface of this pattern or on the surface of another film formed on the pattern. After that, an interlayer insulating film is formed on the upper side of the convex portion by high-density plasma CVD or a high frequency bias sputtering method, and further, a plurality of pixel electrodes are formed on the interlayer insulating film directly or through another film.

Therefore, since the convex portion is formed on the lower ground of the pixel electrode through the interlayer insulating film, first, if the edge portion of each pixel electrode is formed so as to be located on the convex portion. (In other words, if the convex portions are formed so as to be located in the regions that are the gaps between the pixel electrodes adjacent to each other), the vertical electric field generated between each pixel electrode and the counter electrode is generated.
It is relatively strengthened as compared with the lateral electric field generated between pixel electrodes belonging to different pixel electrode groups. That is, since the electric field generally becomes stronger as the distance between the electrodes becomes shorter, the edge of the pixel electrode approaches the counter electrode by the height of the convex portion, and the vertical electric field generated between the two is strengthened. Secondly, regardless of whether or not the edge of each pixel electrode is located on this convex portion, the lateral electric field generated between adjacent pixel electrodes (particularly, pixel electrodes belonging to different pixel electrode groups) is convex. The presence of a portion weakens the dielectric constant of the convex portion and reduces the volume of the electro-optical material through which the transverse electric field passes (by partially replacing the convex portion) with respect to the electro-optical substance of the transverse electric field. The action can be reduced. Therefore, it is possible to reduce the malfunction of the electro-optical material such as the alignment failure of the liquid crystal due to the lateral electric field due to the inversion driving method. The edge portion of the pixel electrode may or may not be located on the convex portion, and may be located in the middle of the inclined or substantially vertical side surface of the convex portion.

In the present invention, in particular, for example, ECR (electron cyclotron resonance) type plasma CVD, ICP
In the high density plasma CVD typified by (inductive coupling) system plasma CVD, helicon wave system plasma CVD or the like, or the bias sputtering method of applying high frequency power so that self bias is applied to the substrate side in the sputtering method, An interlayer insulating film is formed on the lower layer side. Therefore, a convex portion having a gentler step than the step on the surface of the convex portion below the interlayer insulating film appears on the surface of the interlayer insulating film. This is because in high density plasma CVD, the ion density in the plasma is about two orders of magnitude higher than in normal plasma CVD, so that high density plasma is generated even during the deposition of the interlayer insulating film. It is considered that since the just-deposited interlayer insulating film is slightly scraped, its acute angle or right-angled corner is taken and a convex portion having a gentle slope finally appears on the surface of the interlayer insulating film. For example, when a convex portion formed of a rectangular parallelepiped extending in a strip shape along the substrate surface is formed under the interlayer insulating film, the cross-sectional shape of the convex portion has a downward spread in a cross section perpendicular to the longitudinal direction. Three-sided convex parts appear except the base of the trapezoid. The high-density plasma CVD is also possible by using the high frequency bias sputtering method.
The same effect as can be obtained. That is, the action of plasma particles etching the insulating film deposited on the substrate is utilized by applying a self-bias to the substrate. By appropriately selecting the self-bias condition, the difference in sputter etching rate between the flat surface and the side surface of the step on the surface of the insulating film can be changed, so that the step on the surface of the insulating layer is flattened leaving a convex portion with a gentle slope. , The desired shape can be obtained.

As described above, when the step due to the convex portion becomes gentle on the lower ground of the pixel electrode facing the electro-optical material such as liquid crystal, the layer thickness of the electro-optical material is defined near the edge of the opening area of each pixel. Since the step on the surface to be formed is made gentle, the operation failure in the electro-optical material such as the liquid crystal alignment failure due to the step can be reduced. That is, when the convex portion formed by etching or the like remains as it is, the step on the side wall is steep, or the upper and lower ends of the side wall of the convex portion are angular, so that the angle of the convex surface changes sharply. Then, a discontinuous surface is generated in the electro-optical material such as liquid crystal, and operation failure of the electro-optical material such as alignment failure of the liquid crystal occurs. As described above, according to the present invention, not only the malfunction of the electro-optical material due to the lateral electric field can be reduced, but also the malfunction of the electro-optical material due to the step due to the convex portion for reducing the malfunction can be suppressed. For this reason, the light-shielding film for hiding the defective portion of the electro-optical material can be made small, and the aperture ratio of each pixel can be increased without causing image defects such as light leakage.

Further, according to the present invention, at least a part of the convex portion is
Since it is constructed by the presence of a pattern including wirings such as scanning lines and data lines and elements such as TFTs, the manufacturing process is more complicated than the case where the convex portion is formed by a film for forming the convex portion or exclusive etching. The number of steps can be reduced without inviting complication. Further, generally, in order to perform interlayer insulation between the pixel electrode and the wirings, electrodes, etc. existing therebelow, it is essentially necessary to provide an interlayer insulation film between them, so that it has this interlayer insulation function as in the present invention. Using the inter-layer insulating film to obtain the above-mentioned unique effect of the convex portion is
It is extremely excellent in that it does not complicate the laminated structure and the manufacturing process on the substrate.

In addition, as compared with the case where wet etching is performed to make the step of the convex portion gentle, for example, the present invention directly forms the convex portion having the gentle step by high density plasma CVD or high frequency bias sputtering. Therefore, a step having small dimensional variation and high accuracy and high reproducibility can be obtained on the interlayer insulating film which is the base of the pixel electrode.

As a result, the malfunction due to the lateral electric field in the electro-optical material such as liquid crystal can be surely reduced by forming the convex portion, and the formation of the convex portion causes the malfunction due to the step in the electro-optical material such as liquid crystal. Can be suppressed by the interlayer insulating film formed by the high-density plasma CVD or the high frequency bias sputtering method, and finally,
It is relatively easy to manufacture an electro-optical device such as a liquid crystal device that displays a bright and high-quality image with high contrast.

The interlayer insulating film formed by the high density plasma CVD or the high frequency bias sputtering method may be closely arranged with the pixel electrode, or another insulating film or the like may be interposed therebetween. Is. Furthermore, wiring,
High-density plasma CVD with convex parts consisting of patterns of devices, etc.
It is also possible to form another insulating film, a conductive film, or the like with the interlayer insulating film formed by.

In one aspect of the method of manufacturing an electro-optical device of the present invention, the method further comprises the step of forming a material film for forming the convex portion separately from the pattern, and the convex portion is replaced with the pattern. Alternatively, or in addition, it is at least partially constructed by the presence of the material film.

According to this aspect, not only the pattern including the wiring, the element, etc., but also the convex portion is positively formed by using the material film for forming the convex portion.
It is possible to arbitrarily construct a convex portion having a desired height. Moreover, even if such a convex portion is formed steeply, the interlayer insulating film is formed on the convex portion by high density plasma CVD, so that a gentle step can be obtained on the lower ground of the pixel electrode.

In another aspect of the method of manufacturing an electro-optical device of the present invention, the method further comprises a step of digging a groove having a predetermined pattern on the first substrate, and the convex portion is used instead of or in addition to the pattern. , At least partially constructed by the presence of said grooves.

According to this aspect, not only the pattern including the wiring, the element, etc., but also the groove formed in the substrate by etching or the like is used to form the convex portion. It is also possible not to form the convex portion.

In another aspect of the method of manufacturing an electro-optical device of the present invention, a step of forming another interlayer insulating film on the first substrate and a step of digging a groove having a predetermined pattern on the other interlayer insulating film. And the protrusions are at least partially constructed by the presence of the grooves instead of or in addition to the pattern.

According to this aspect, not only the pattern including the wiring, the element, etc. but also the groove formed in the other interlayer insulating film by etching the other interlayer insulating film formed on the substrate is utilized. Since the convex portion is formed by forming the convex portion, it is possible to prevent the convex portion from being formed particularly in the region to be flattened.

In another aspect of the method for manufacturing an electro-optical device of the present invention, the method further comprises a step of subjecting the surface of the laminate on the substrate to a CMP process before the step of forming the pattern is completed, The protrusions are at least partially constructed by the pattern formed on the CMP-treated surface.

According to this aspect, before the completion of the step of forming the pattern, the surface is temporarily flattened by performing the CMP process, and then the convex portion is formed by forming a pattern or the like on the flattened surface. Therefore, the height and shape of the convex portion can be controlled relatively easily and accurately.

In place of or in addition to such a CMP treatment, a step of forming a flattened insulating film by applying a fluid insulating film material, or including a wiring or an element is included. A step of forming a groove in which the pattern is embedded may be provided in advance.

In another aspect of the method of manufacturing the electro-optical device of the present invention, the convex portion is a gap between the pixel electrode and a first region along a first direction in a region of the gap between the pixel electrodes. It is constructed in only one of the second region and the second region along the second direction which intersects the first direction.

According to this aspect, the projections extending in stripes corresponding to the pixel columns or the pixel rows are formed in the image display region, whereby the transverse electric field in the direction crossing the stripe projections is formed. The adverse effect due to can be reduced. Moreover, in the gap between the pixel electrodes where the stripe-shaped convex portions are not formed, the malfunction of the electro-optical material due to the step hardly occurs.

In the aspect in which the convex portion is formed only in one of the first and second regions, the convex portion has a gap between the adjacent pixel electrodes which are driven in reverse with different polarities. Constructed as a region.

With this structure, a lateral electric field is generated,
Adjacent pixel electrodes belonging to different pixel electrode groups (ie,
Since the convex portions are provided only between the pixel electrodes to which the electric potentials of opposite polarities are applied, adjacent pixel electrodes belonging to the same pixel electrode group in which a horizontal electric field hardly occurs (that is, electric potentials of the same polarity are applied). No convex portion is provided between the pixel electrodes). Therefore, in the above-described 1H inversion drive or 1S inversion drive, the convex portion formed only in the effective portion causes
The adverse effect of the lateral electric field can be reduced extremely effectively. Further, it is advantageous that the operation failure of the electro-optical material due to the step is not caused due to the convex portion that does not contribute to reducing the adverse effect of the lateral electric field.

Instead of providing such a stripe-shaped convex portion, a relatively high convex portion is provided in a gap between adjacent pixel electrodes included in different pixel electrode groups, and the same pixel electrode group is provided. Even if a relatively low convex portion is provided in the gap between the pixel electrodes adjacent to each other included in, the similar effect can be obtained.

In the aspect in which the convex portion is formed only in one of the first and second regions, the other region of the first region and the second region is formed before the interlayer insulating film is formed. In addition, the method may further include the step of forming another wiring or element for driving the pixel electrode.

According to this structure, in the gap between the pixel electrodes where the convex portion is not formed, the lower ground of the pixel electrode rises in a convex shape depending on the thickness of the other wiring or element due to the presence of the other wiring or element. Also with respect to this bulge, the level difference becomes gentle due to the interlayer insulating film formed by high-density plasma CVD, similarly to the convex portion. Therefore, the alignment defect of the electro-optical material due to the step is reduced.

In another aspect of the method of manufacturing an electro-optical device of the present invention, the convex portions are constructed in a lattice shape along a region serving as a gap between the pixel electrodes.

According to this aspect, since the projections located on the four sides of each pixel are provided in the image display area, the lateral electric field in the direction traversing vertically and horizontally between the pixels is exhibited especially when the dot inversion drive is performed. The adverse effect due to can be reduced.

In another aspect of the method of manufacturing the electro-optical device of the present invention, the element for driving the pixel electrode formed on the first substrate includes a single crystal semiconductor layer formed by bonding SOI.

According to this aspect, the element performance can be improved by forming the element using the single crystal semiconductor as the active layer. In such bonding, generally, the supporting substrate and the surface of the single crystal layer are made flat and mirror-finished to bond the two, so that it is difficult to freely control the uneven shape after the element or wiring is formed, but as described above. High density C
Since the interlayer insulating film is formed by VD plasma, the shape control on the lower ground of the pixel electrode can be facilitated and the liquid crystal alignment defect can be prevented.

In order to solve the above problems, the electro-optical device of the present invention comprises an electro-optical substance sandwiched between a pair of first and second substrates, and is inverted on the first substrate at a first cycle. A plurality of pixel electrodes arranged in a plane and including a first pixel electrode group to be driven and a second pixel electrode group to be inverted and driven in a second cycle complementary to the first cycle; A pattern including a wiring and an element for driving the pixel electrode, and an upper side of a convex portion which is at least partially constructed by the existence of the pattern in a region which is a gap between the pixel electrodes adjacent to each other in a plan view during a manufacturing process. And an interlayer insulating film formed on the lower side of the pixel electrode by high-density plasma CVD and having a step more gentle than the step on the surface of the protrusion, on the second substrate. Facing multiple pixel electrodes It comprises a counter electrode.

According to the electro-optical device of the present invention, a lateral electric field is generated between adjacent pixel electrodes belonging to different pixel electrode groups (that is, adjacent pixel electrodes to which a potential of opposite polarity is applied). However, a convex portion is formed on the lower ground of the pixel electrode via an interlayer insulating film. Therefore, first, if the edge portions of the pixel electrodes are formed so as to be located on the convex portions, a vertical electric field generated between the pixel electrodes and the counter electrode is generated between the adjacent pixel electrodes. It is relatively strengthened compared to the lateral electric field. Secondly, regardless of whether or not the edge of each pixel electrode is located on this convex portion, the lateral electric field generated between the adjacent pixel electrodes depends on the dielectric constant of the convex portion due to the presence of the convex portion. The action of the lateral electric field on the electro-optical material can also be reduced by reducing the volume of the electro-optical material that is weakened and through which the lateral electric field passes.

In the present invention, in particular, the interlayer insulating film on the lower layer side of the pixel electrode is formed by the high density plasma CVD or the high frequency bias sputtering method.
A convex portion having a gentler step than the step on the surface of the convex portion below the interlayer insulating film appears on the surface of the interlayer insulating film. Therefore, it is possible to reduce malfunctions in the electro-optical material such as alignment defects of the liquid crystal due to the step.

For these reasons, the light-shielding film for hiding the defective portion of the electro-optical material can be made small, so that the aperture ratio of each pixel can be increased without causing image defects such as light leakage.

As a result, the malfunction due to the lateral electric field in the electro-optical material such as liquid crystal can be surely reduced by forming the convex portion, and the formation of the convex portion causes the malfunction due to the step in the electro-optical material such as liquid crystal. Can be suppressed by the interlayer insulating film formed by high-density plasma CVD or high-frequency bias sputtering, and finally, high-contrast, bright and high-quality image display can be performed.

The electro-optical device of the present invention includes various aspects manufactured by the various aspects of the above-described method of manufacturing the electro-optical device of the present invention.

The present invention can be applied to various types of electro-optical devices other than the transmission type and the reflection type.

In order to solve the above problems, the electronic apparatus of the present invention includes the above-described electro-optical device of the present invention (including those manufactured by various aspects of the above-described method of manufacturing the electro-optical device of the present invention). It is equipped with.

Since the electronic equipment of the present invention comprises the above-mentioned electro-optical device of the present invention, a projection type display device, a liquid crystal television, a mobile phone, which is capable of bright and high quality image display,
Various electronic devices such as an electronic notebook, a word processor, a viewfinder type or a monitor direct-viewing type video tape recorder, a workstation, a videophone, a POS terminal, and a touch panel can be realized.

The operation and other advantages of the present invention will be apparent from the embodiments described below.

[0049]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. The following embodiments apply the electro-optical device of the present invention to a liquid crystal device.

(First Embodiment) A first embodiment of the present invention will be described with reference to FIGS.

First, the structure of the electro-optical device according to the first embodiment will be described with reference to FIGS. 1 to 5. Figure 1
Is an equivalent circuit of various elements, wirings, and the like in a plurality of pixels formed in a matrix that form an image display area of the electro-optical device. FIG. 2 is a plan view of a plurality of pixel groups adjacent to each other on a TFT array substrate on which data lines, scanning lines, pixel electrodes, etc. are formed. 3 is a sectional view taken along the line AA ′ of FIG. 2, FIG. 4 is a sectional view taken along the line BB ′ of FIG. 2, and FIG.
FIG. 3 is a sectional view taken along line CC ′ of FIG. 2. 3 to 5, the scales of the layers and members are different from each other in order to make the layers and members recognizable in the drawings.

In FIG. 1, a pixel electrode 9a and a TFT 30 for controlling switching of the pixel electrode 9a are respectively provided in a plurality of pixels which are formed in a matrix and constitute an image display area of the electro-optical device according to the present embodiment. Are formed, and the data line 6a to which the image signal is supplied is electrically connected to the source of the TFT 30. The image signals S1, S2, ..., Sn to be written to the data line 6a may be line-sequentially supplied in this order, or may be supplied to each of a plurality of adjacent data lines 6a in groups. good. In addition, the scanning line 3 is connected to the gate of the TFT 30.
a is electrically connected, and the scanning signals G1, G2, ..., Gm are pulsed to the scanning line 3a at a predetermined timing.
Is applied line-sequentially in this order.
The pixel electrode 9a is electrically connected to the drain of the TFT 30, and by closing the switch of the TFT 30 which is a switching element for a certain period, the data line 6
The image signals S1, S2, ..., Sn supplied from a are written at a predetermined timing. The image signals S1, S2, ..., Sn having a predetermined level written in liquid crystal as an example of an electro-optical material via the pixel electrode 9a are generated by a counter electrode (described later) formed on a counter substrate (described later). Held for a period of time. The liquid crystal modulates light by changing the orientation and order of the molecular assembly depending on the applied voltage level, and enables gradation display. In the normally white mode, the transmittance for incident light is reduced according to the voltage applied in each pixel unit, and in the normally black mode, the incident light is incident according to the voltage applied in each pixel unit. The transmittance for light is increased, and light having a contrast corresponding to the image signal is emitted from the electro-optical device as a whole. Here, in order to prevent the held image signal from leaking, the storage capacitor 70 is added in parallel with the liquid crystal capacitor formed between the pixel electrode 9a and the counter electrode.

In FIG. 2, a plurality of transparent pixel electrodes 9 are arranged in a matrix on the TFT array substrate of the electro-optical device.
a (the outline is shown by the dotted line portion 9a '), and the data line 6a and the scanning line 3a are provided along the vertical and horizontal boundaries of the pixel electrode 9a. Further, the capacitance line 3b is provided in a stripe shape along with the scanning line 3a. More specifically, the capacitance line 3b has a main line portion that is parallel to the scanning line 3a, and a protruding portion that protrudes upward in the drawing along the data line 6a from a portion of the main line portion that intersects the data line 6a. .

Further, the scanning line 3a is arranged so as to oppose the channel region 1a 'shown by the hatched region on the lower right side of the semiconductor layer 1a, and the scanning line 3a functions as a gate electrode. In this way, the scanning line 3a and the data line 6
TFTs 30 for pixel switching, each of which has a scanning line 3a as a gate electrode, are provided in a channel region 1a 'at a position intersecting with "a".

As shown in FIGS. 2 and 3, the data line 6a
Are electrically connected to the high concentration source region 1d of the semiconductor layer 1a through the contact holes 5. On the other hand,
The pixel electrode 9a is electrically connected to the high-concentration drain region 1e of the semiconductor layer 1a via the contact hole 8.

The pixel potential side capacitance electrode 1f extending from the high-concentration drain region 1e and the portion of the capacitance line 3b as the fixed potential side capacitance electrode are the insulating film 2 as a dielectric film.
The storage capacitor 70 is constructed by being opposed to each other via. The capacitance line 3b extends from the image display area in which the pixel electrode 9a is arranged to the periphery thereof, is electrically connected to the constant potential source, and has a fixed potential.

3 to 5, the electro-optical device is
It is provided with a transparent TFT array substrate 10 and a transparent counter substrate 20 arranged to face it. The TFT array substrate 10 is made of, for example, a quartz substrate, a glass substrate, or a silicon substrate, and the counter substrate 20 is made of, for example, a glass substrate or a quartz substrate.

The TFT array substrate 10 has a pixel electrode 9a.
Is provided, and an alignment film 16 subjected to a predetermined alignment treatment such as a rubbing treatment is provided on the upper side thereof.
The pixel electrode 9a is made of, for example, a transparent conductive thin film such as an ITO (Indium Tin Oxide) film. The alignment film 16 is made of, for example, an organic thin film such as a polyimide thin film.

On the other hand, the counter substrate 20 is provided with a counter electrode 21 over the entire surface thereof, and an alignment film 22 subjected to a predetermined alignment treatment such as rubbing treatment is provided below the counter electrode 21. There is. The counter electrode 21 is made of, for example, a transparent conductive thin film such as an ITO film. The alignment film 22 is made of an organic thin film such as a polyimide thin film. Further, as shown in FIGS. 3 and 5, the counter substrate 20 is provided with a light shielding film 23 generally called a black mask or a black matrix (BM) in the non-opening region of each pixel. Therefore, incident light hardly enters 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 30 from the counter substrate 20 side. Further, the light shielding film 23 has a function of improving the contrast ratio and preventing color mixture of color materials when a color filter is formed. In the present embodiment, the light-shielding data line 6a made of Al or the like is used to shield the portion of the non-opening area of each pixel along the data line 6a from light, so that the data line 6a of the opening area of each pixel is shielded. May be defined (in this case, the stripe-shaped light-shielding film 23 along the scanning line 3a may be provided), and the non-opening region along the data line 6a may be defined. The light shielding film 23 provided on the counter substrate 20 may be redundantly or independently provided (in this case, the lattice-shaped light shielding film 23 is provided). Instead of or in addition to such light shielding, in the laminated body on the TFT array substrate 10,
A built-in light-shielding film made of a refractory metal film or the like may be provided to define part or all of the opening region of each pixel.

As shown in FIGS. 3 to 5, between the TFT array substrate 10 and the counter substrate 20 which are arranged as described above and in which the pixel electrode 9a and the counter electrode 21 are arranged to face each other, A liquid crystal, which is an example of an electro-optical material, is enclosed in a space surrounded by a sealing material described later to form a liquid crystal layer 50. The liquid crystal layer 50 has a predetermined alignment state by the alignment films 16 and 22 in a state where the electric field from the pixel electrode 9a is not applied. The liquid crystal layer 50 is made of, for example, liquid crystal in which one kind or several kinds of nematic liquid crystals are mixed. The sealing material is an adhesive for bonding the TFT array substrate 10 and the counter substrate 20 around their periphery, for example, an adhesive made of a photocurable resin or a thermosetting resin, and for keeping the distance between both substrates a predetermined value. Gap material such as glass fiber or glass beads is mixed.

Further, a base insulating film 12 is provided below the pixel switching TFT 30. Since the base insulating film 12 is formed on the entire surface of the TFT array substrate 10, the surface of the TFT array substrate 10 is roughened at the time of polishing, dirt left after cleaning, and the like for pixel switching.
It has a function of preventing deterioration of the characteristics of the FT 30.

The pixel switching TFT 30 is an LD
The scanning line 3a has a D (Lightly Doped Drain) structure, 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.
An insulating film 2 including a gate insulating film that insulates the semiconductor layer 1a from the semiconductor layer 1a, 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 of the semiconductor layer 1a.
In addition, the high concentration drain region 1e is provided.

A high concentration source region 1d is formed on the scanning line 3a.
Contact hole 5 and high-concentration drain region 1 leading to
A first interlayer insulating film 4 is formed in which contact holes 8 each leading to e are formed.

The data line 6a is formed on the first interlayer insulating film 4, and the second interlayer insulating film 80 having the contact hole 8 opened is formed thereon.

In the present embodiment, particularly, the second interlayer insulating film 80
In the manufacturing process,
It is formed by high density plasma CVD. Therefore, as shown in FIG. 4, in the non-aperture region of each pixel along the data line 6a (that is, in the region excluding the aperture region in which light actually contributing to display is transmitted or reflected in each pixel),
A convex portion having a gentle step and a trapezoidal cross section is formed on a convex portion having a steep step formed on the surface of the data line 6a by the data line 6a and the storage capacitor 70 constituting an example of the pattern according to the present invention. The part 81 is constructed.
Further, as shown in FIG. 5, in the non-aperture region of each pixel along the scanning line 3a, the surface of the first interlayer insulating film 4 is formed on the surface of the first interlayer insulating film 4 by the scanning line 3a and the storage capacitor 70 that form an example of the pattern according to the present invention. A convex portion 82 having a gentle step and a trapezoidal cross section is formed on the formed convex portion having a steep step.
Is being built. The convex portions 81 and the convex portions 82 form lattice-shaped convex portions in a plan view along the non-aperture area of each pixel over the entire image display area.

Here, if the second interlayer insulating film is formed by normal CVD or normal plasma CVD, for example, the first interlayer insulating film 4 shown in FIGS. 3 to 5 is formed on the surface thereof. The steep convex portions are formed in accordance with the patterns of the wirings, elements, etc. existing below them. Then, if the pixel electrode 9a is formed on the second interlayer insulating film having such a steep convex portion, a discontinuous surface is generated in the liquid crystal layer 50, and an alignment defect of the liquid crystal layer 50 is generated. Of.

However, in the present embodiment, the pixel electrode that defines the layer thickness of the liquid crystal layer 50 near the edge of the opening region of each pixel is formed by the second interlayer insulating film 80 formed by the high density plasma CVD or the high frequency bias sputtering method. Since the step on the lower ground surface of 9a is made gentle, the misalignment of the liquid crystal layer 50 caused by the step can be reduced by the amount of the step.

In this embodiment, the 1H inversion driving method is used among the various conventional inversion driving methods described above. As a result, it is possible to perform image display in which the flicker that occurs in the frame or field cycle and particularly vertical crosstalk is reduced while avoiding the deterioration of the liquid crystal due to the application of the DC voltage.

Referring to FIG. 6, the pixel electrodes 9 adjacent to each other in the 1H inversion driving method adopted in this embodiment.
The relationship between the voltage polarity of a and the generation region of the horizontal electric field will be described.

That is, as shown in FIG. 6A, liquid crystal indicated by + or − for each pixel electrode 9a during the period in which the image signal of the nth (where n is a natural number) field or frame is displayed. The polarity of the drive voltage is not inverted, and the pixel electrodes 9a are driven with the same polarity for each row. Thereafter, as shown in FIG. 6B, when displaying the image signal of the (n + 1) th field or one frame, the voltage polarity of the liquid crystal drive voltage in each pixel electrode 9a is inverted, and the (n + 1) th field or one frame of During the period in which the image signal is displayed, the polarity of the liquid crystal drive voltage indicated by + or − is not inverted for each pixel electrode 9a, and the pixel electrode 9a is driven with the same polarity for each row. Then, the states shown in FIGS. 6A and 6B are repeated at a cycle of one field or one frame, and the driving by the 1H inversion driving method in the present embodiment is performed. As a result, according to this embodiment, it is possible to perform image display with reduced crosstalk and flicker while avoiding deterioration of the liquid crystal due to application of a DC voltage. The 1H inversion driving method is advantageous in that there is almost no vertical crosstalk as compared with the 1S inversion driving method.

As can be seen from FIGS. 6A and 6B, in the 1H inversion driving method, the lateral electric field generation region C1 is always the gap between the pixel electrodes 9a adjacent to each other in the vertical direction (Y direction). It will be in the vicinity.

Therefore, as shown in FIGS. 3 and 5, in the present embodiment, the convex portion 82 is formed, and the vertical electric field near the edge of the pixel electrode 9a arranged on the convex portion 82 is strengthened and the lateral electric field is weakened. To do so. More specifically, as shown in FIG. 5, the distance between the edge of the pixel electrode 9 a arranged on the convex portion 82 and the counter electrode 21 is reduced by the convex portion 82. Therefore, in the horizontal electric field generation region C1 shown in FIG. 6, the vertical electric field between the pixel electrode 9a and the counter electrode 21 can be strengthened. And FIG. 3 and FIG.
In the above, since the gap between the pixel electrodes 9a adjacent to each other is constant, the magnitude of the lateral electric field that strengthens as the gap narrows is also constant. Therefore, the horizontal electric field generation region C1 shown in FIG.
In, the vertical electric field can be strengthened with respect to the horizontal electric field.

Further, the presence of the convex portion 82 made of an insulating film weakens the strength of the lateral electric field, and the liquid crystal portion receiving the lateral electric field is reduced by the amount of the convex portion 82 in which the lateral electric field is present. The action of the lateral electric field on the liquid crystal layer 50 can be reduced.

As a result, by making the vertical electric field more dominant, it is possible to prevent the liquid crystal alignment failure due to the horizontal electric field in the horizontal electric field generation region C1.

As a result of the above, according to this embodiment, focusing on the characteristics of the lateral electric field generated in the 1H inversion driving method,
By providing the convex portion 82 in the lateral electric field generation region C1,
By relatively strengthening the vertical electric field, the adverse effect of the horizontal electric field is reduced. By reducing the liquid crystal misalignment due to the horizontal electric field in this manner, the light-shielding film 23 for hiding the liquid crystal misalignment can be made small (however, the liquid crystal misalignment caused by the step in the convex portion 82 is covered. To hide
It is desirable to set the width of the light shielding film 23 to be slightly wider than the width of the convex portion 82). Therefore, it is possible to increase the aperture ratio of each pixel without causing image defects such as light leakage (and the like), and finally it is possible to display a bright, high-quality image with a high contrast ratio.

In particular, according to this embodiment, the convex portion 82
By forming the step to be gentle, it is possible to prevent the liquid crystal layer 50 from malfunctioning due to the step.
As a result, both the malfunction of the liquid crystal layer 50 due to the lateral electric field and the malfunction of the liquid crystal layer 50 due to the step can be reduced in a well-balanced manner, and a liquid crystal device that performs bright and high-quality image display with high contrast can be provided. realizable.

Further, in this embodiment, the edge of the pixel electrode 9a may be located at the edge of the upper surface of the convex portion 82 extending in the longitudinal direction in the width direction. With this structure, the distance between the pixel electrode 9a and the counter electrode 21 at the edge can be shortened by maximally utilizing the height of the convex portion 82. At the same time, by maximizing the width of the upper surface of the convex portion 82, it is possible to widen the interval between the adjacent pixel electrodes 9a in which a lateral electric field is generated. As a result, the vertical electric field can be strengthened with respect to the horizontal electric field in the horizontal electric field generation region C1 by utilizing the shape of the convex portion 82 extremely efficiently.

In the present embodiment, as described with reference to FIG. 6, the convex portion 82 is provided corresponding to the horizontal electric field generation region C1 along the scanning line 3a. However, as shown in FIGS. The convex portion 81 is provided corresponding to the non-opening region of the pixel along the line 6a. This is because a slight lateral electric field is generated depending on the image signal even in the non-aperture area of the pixel along the data line 6a. However, since the lateral electric field generated between the pixel electrodes arranged side by side with the same liquid crystal driving voltage and having the same polarity (see FIG. 6) is weak, the convex portion 81 is larger than the convex portion 82 as seen from FIG. The height is low.
For example, when the layer thickness of the liquid crystal layer 50 is 3 μm, the protrusions 8
2 is about 0.5 μm, and the height of the convex portion 81 is 0.
It is about 35 μm.

In this embodiment, the pixel electrodes 9 adjacent to each other are arranged.
The relationship between the voltage polarity of a and the lateral electric field generation region C2 shown in FIG. 7 is 1S inversion driving method (that is, the polarity of the liquid crystal driving voltage changes for each column, and the lateral electric field generation region C2 corresponds to the data line 6
In the case of adopting a method of forming a pixel gap along a), the protrusion 81 may be formed higher than the protrusion 82 in the configuration shown in FIGS. 3 to 5 (for example, the layer of the liquid crystal layer 50). When the thickness is 3 μm, the height of the convex portion 81 is 0.5 μm
The height of the convex portion 82 may be set to about 0.35 μm).

Alternatively, in the present embodiment, the dot inversion driving method (that is, the polarity of the liquid crystal driving voltage is changed for each column and for each row, and the horizontal electric field is generated in the data line 6a and the scanning line 3.
In the case of adopting a method of forming a pixel gap along a), it is sufficient to form both the convex portion 81 and the convex portion 82 in the configuration shown in FIGS. 3 to 5 (for example, the liquid crystal layer 50). When the layer thickness is 3 μm, the height of the convex portion 81 is 0.
The height of the protrusions 82 may be about 5 μm and the height of the protrusions 82 may be about 0.5 μm).

Further, in the 1H inversion driving method according to the present invention, the polarity of the driving voltage may be inverted every one row, every two adjacent rows or every plural rows. Similarly, in the 1S inversion driving method according to the present invention, the polarity of the driving voltage may be inverted for each column, or may be inverted for every two columns adjacent to each other or for every plural columns. Alternatively, the polarity of the drive voltage may be inverted for each block including a plurality of pixel electrodes.

In the embodiment described above, in the switching TFT 30, the channel portion 1a ′, the low concentration source region 1b and the low concentration drain region 1c, and the high concentration source region 1d and the high concentration drain region 1e are made of a semiconductor material. Has a polycrystalline structure or a single crystal structure. Further, the pixel switching TFT 30 preferably has an LDD structure as shown in FIG. 3, but may have an offset structure in which the low concentration source region 1b and the low concentration drain region 1c are not implanted with impurity ions, and scanning is performed. A self-aligned TFT may be used in which high-concentration source and drain regions are formed in a self-aligned manner by implanting high-concentration impurity ions with the gate electrode formed of part of the line 3a as a mask. Further, in the present embodiment, T for pixel switching is used.
Although only one gate electrode of the FT 30 is arranged between the high-concentration source region 1d and the high-concentration drain region 1e, two or more gate electrodes may be arranged between them. As described above, when the TFT is configured with dual gates or triple gates or more, it is possible to prevent the leak current at the junction between the channel and the source / drain regions, and reduce the current when off.

Further, the semiconductor layer 1a constituting the TFT 30
Can be formed from various silicon films such as a high temperature polysilicon film, a low temperature polysilicon film, a single crystal silicon film, and an amorphous silicon film.

Furthermore, even if the present invention is applied to not only the projection type or transmission type liquid crystal device but also the reflection type liquid crystal device, the effect of reducing the alignment defect of the liquid crystal due to the horizontal electric field according to the present embodiment is the same. can get.

(Manufacturing Process) Next, the TFT which constitutes the electro-optical device in the embodiment having the above-mentioned constitution
The manufacturing process on the array substrate side will be described with reference to FIGS. 8 is a process diagram showing each layer on the TFT array substrate side in each process corresponding to the BB ′ cross section of FIG. 2 similarly to FIG. 4, and FIG. 9 is similar to FIG. It is a process drawing shown corresponding to the CC 'cross section of.

First, as shown in step (a) of FIGS. 8 and 9, a quartz substrate, a hard glass substrate, a silicon substrate, or the like is used.
On the FT array substrate 10, for example, normal pressure or low pressure CVD
TEOS (Tetra-Ethyl-Ortho-Silicate) gas, TEB (Tetra-Ethyl boat rate)
NSG, PSG, BSG, BPS using gas, TMOP (Tetra Methyl Oxy Foslate) gas, etc.
A base insulating film 12 made of a silicate glass film such as G, a silicon nitride film, a silicon oxide film, or the like and having a film thickness of about 500 to 2000 nm is formed. Next, a semiconductor layer is formed on the base insulating film 12. The semiconductor layer has a polycrystalline structure or a single crystal structure. In the case of a polycrystalline semiconductor layer, an amorphous silicon film is formed by low pressure CVD or the like.
By performing an annealing treatment at a temperature of about 0 ° C., the polysilicon film is solid-phase grown. Alternatively, a method of directly forming a polysilicon film by a low pressure CVD method or the like without passing through the amorphous silicon film can be used.

Further, in the case of forming a single crystal semiconductor layer, a bonding method in which a single crystal substrate is bonded to a supporting substrate and then the single crystal substrate side is thinned can be used. Although silicon is preferably used as the single crystal semiconductor, any material that exhibits characteristics as a semiconductor and can form a switching element can be similarly used. A structure in which such a thin film silicon single crystal layer is formed on an insulating layer is particularly suitable for SO.
Such a method is called a bonding method, and such a substrate is called a bonding SOI substrate. In this bonding method, a method using hydrogen ion implantation and annealing, which is known as one of methods for forming a single crystal silicon layer having excellent film thickness uniformity, is preferably used. In this process, hydrogen ion implantation with a prescribed implantation depth is performed on a single crystal substrate made of silicon for forming a thin film layer, and this single crystal silicon substrate is subjected to T
500 ° C. to 6 after being bonded to the FT array forming substrate
By performing an annealing treatment at about 00 ° C., the single crystal silicon substrate is separated while leaving an extremely thin single crystal film on the TFT array forming substrate. The obtained single crystal silicon film has few defects, high quality, and extremely high film thickness uniformity.

As another method for forming a single crystal silicon layer having excellent film thickness uniformity, a known method for transferring a single crystal silicon layer epitaxially grown into a porous silicon layer to an array substrate can be used. This is because after a single crystal silicon layer is epitaxially grown on the surface of the silicon substrate whose surface has been made porous by electrolytic polishing, this is bonded to the array substrate, and the fragile porous layer is crushed by physical means such as water jet, It divides the silicon substrate and the single crystal silicon layer. After the division, the porous silicon residue remaining on the surface of the epitaxial single crystal silicon layer is removed with a high selectivity by an etchant containing HF / H ₂ O ₂ . As a result, the single crystal silicon film transferred onto the array substrate has few defects, high quality, and extremely high film thickness uniformity.

Next, by subjecting the polysilicon or single crystal silicon film to a photolithography process, an etching process, etc., the semiconductor layer 1a having a predetermined pattern including the pixel potential side capacitance electrode 1f as shown in FIG.
To form.

Next, by thermal oxidation or the like, the insulating film 2 including the dielectric film for forming the storage capacitor is formed together with the gate insulating film of the TFT 30 shown in FIGS. As a result, the semiconductor layer 1a has a thickness of about 30 to 150 nm, preferably about 35 to 50 nm, and the insulating film 2 has a thickness of about 20 to 150 nm, preferably about 30 nm. It will be ~ 100 nm thick. Next, a polysilicon film is deposited to a thickness of about 100 to 500 nm by a low pressure CVD method or the like, and then P (phosphorus) is thermally diffused to make the polysilicon film conductive, and then a photolithography step and an etching step. As a result, the scanning lines 3a and the capacitance lines 3b having a predetermined pattern as shown in FIG. 2 are formed. The scanning lines 3a and the capacitance lines 3b may be formed of a metal alloy film such as a refractory metal or a metal silicide, or may be a multi-layer wiring combined with a polysilicon film or the like. Next, by doping the impurity ions in two steps of low concentration and high concentration, the low concentration source region 1b and the low concentration drain region 1c, the high concentration source region 1d and the high concentration drain region 1e are included.
A pixel switching TFT 30 having a DD structure is formed.

In parallel with the step (a) of FIGS. 8 and 9, peripheral circuits such as a data line driving circuit and a scanning line driving circuit composed of TFTs are formed in the peripheral portion on the TFT array substrate 10. May be.

Next, as shown in the step (b) of FIG. 8 and FIG. 9, for example, at normal pressure or so as to cover the laminated body composed of the scanning lines 3a, the capacitance lines 3b, the insulating film 2 and the base insulating film 12. Using low pressure CVD method or TEOS gas, NSG, PS
A first interlayer insulating film 4 made of a silicate glass film such as G, BSG, BPSG, a silicon nitride film, a silicon oxide film, or the like is formed. The first interlayer insulating film 4 is, for example, 1000 to
The film thickness is about 2000 nm. It should be noted that an annealing treatment at about 1000 ° C. may be performed to activate the semiconductor layer 1a in parallel with or before or after the thermal firing. Then, a contact hole 5 for electrically connecting the data line 6a and the high-concentration source region 1d of the semiconductor layer 1a shown in FIG. 3 is opened in the first interlayer insulating film 4 and the insulating film 2, and scanning is performed. A contact hole for connecting the line 3a and the capacitor line 3b to a wiring (not shown) in the peripheral region of the substrate can be formed by the same process as the contact hole 5. Then, a low resistance metal film such as Al or a metal silicide film is deposited on the first interlayer insulating film 4 by a sputtering process or the like to a thickness of about 100 to 500 nm, and then a photolithography process and an etching process are performed. , The data line 6a is formed.

Next, as shown in step (c) of FIGS. 8 and 9, a second interlayer insulating film 80 is formed on the data line 6a. The material itself of the second interlayer insulating film 80 is the same as that of the base insulating film 12.
Alternatively, as with the first interlayer insulating film 4, NSG, PSG, BS
It is made of a silicate glass film such as G or BPSG, a silicon nitride film, a silicon oxide film, or the like. In the present embodiment, in particular, high quality represented by, for example, ECR system plasma CVD, ICP system plasma CVD, and helicon wave system plasma CVD. The second interlayer insulating film 80 is formed by density plasma CVD or high frequency bias sputtering.
In the case of high-density plasma CVD, the ion density in the plasma is about two orders of magnitude higher than in the case of normal plasma CVD, so that the high-density plasma was just deposited during the interlayer insulating film deposition. The deposition is continued while the interlayer insulating film is slightly scraped. For this reason, on the convex portion (see FIG. 8) having a steep step having a side wall formed by the surface of the data line 6a or the like and rising substantially at a right angle, or by the surface formed by the surface of the scanning line 3a, the capacitance line 3b, or the like, a substantially right angle. Finally, the convex portion 81 and the convex portion 82 having a gentle slope are secondly formed on the convex portion (see FIG. 9) having a steep step having a side wall.
It can be formed from the interlayer insulating film 80. For example, when the layer thickness of the liquid crystal layer 50 is 3 μm, the height of the convex portion 82 is 0.5 μm.
The high density plasma CVD is performed so that the height of the convex portion 81 is about 0.35 μm. Even when the insulating film depositing means using high frequency bias sputtering is used, the correlation insulating layer on the substrate to which the bias is applied is slightly scraped by the plasma, so that the high density plasma CV is used.
It is possible to obtain a convex shape substantially similar to that of D.

Subsequently, as shown in FIG. 3, the pixel electrode 9
The contact hole 8 for electrically connecting a and the high-concentration drain region 1e is formed with the second interlayer insulating film 80 and the first interlayer insulating film by dry etching such as reactive ion etching or reactive ion beam etching or wet etching. Open the membrane 4.

Next, as shown in step (d) of FIGS. 8 and 9, the second interlayer insulating film 8 in which the contact hole 8 is opened.
Then, a transparent conductive thin film such as an ITO film is deposited on the substrate 0 by sputtering to a thickness of about 50 to 200 nm, and the pixel electrode 9a is formed by a photolithography process and an etching process.

When the electro-optical device is used as a reflection type, the pixel electrode 9a may be formed of an opaque material having a high reflectance such as Al. On top of that, the alignment film 16
To form. A rubbing process is preferably performed on the alignment film 16 in parallel with the step due to the larger convex portion 82.

As described above, according to the manufacturing method of this embodiment, since the second interlayer insulating film 80 is formed by the high density plasma CVD or the high frequency bias sputtering method, the convex portions 81 and the convex portions 82 having a gentle step are formed. And the data lines 6a, the scanning lines 3a, the capacitance lines 3b, and the TFTs.
By controlling the shape of the convex portion composed of 30, the storage capacitor 70 and the like and controlling the film forming conditions in the high density plasma CVD or the high frequency bias sputtering method, the accuracy of the height, shape or dimension of the convex portion 81 and the convex portion 82 is controlled. Can be significantly increased. For example, as compared with the case where wet etching is performed to make the step of the convex portion gentle, the dimensional variation in the convex portion 81 and the convex portion 82 is
The size can be reduced to several tenths to tenths or less, and dimensional accuracy or shape accuracy can be remarkably improved.

Particularly, in this embodiment, the convex portion 81 and the convex portion 8 are formed.
2 is the wiring such as the scanning line 3a and the data line 6a and the TFT 30.
Since it is constructed by the existence of a pattern that includes elements such as the above, compared to the case where the convex portion is formed by a convex-forming film or a dedicated etching, the manufacturing process does not become complicated, and the number of steps Can be reduced. Further, generally, in order to perform interlayer insulation between the pixel electrode 9a and the data line 6a existing therebelow, it is necessary to provide the second interlayer insulating film 80 between them. Therefore, forming the convex portions 81 and the convex portions 82 while performing interlayer insulation by the second interlayer insulating film 80 is very excellent in that it does not complicate the laminated structure and the manufacturing process on the substrate 10.

As a result, in the region where the horizontal electric field is generated, the convex portions 81 and 82 surely reduce the liquid crystal alignment defect due to the horizontal electric field, and the second interlayer insulating film 80 is formed by the high density plasma CVD or the high frequency bias sputtering method. By forming by (1), it is possible to relatively easily manufacture a liquid crystal device with high device reliability that can reduce liquid crystal alignment defects due to steps.

Here, the relationship between the inclination of the side surface of the convex portion 81 and the convex portion 82 and the rubbing direction will be described with reference to FIG.

As shown in FIG. 10 (a), the liquid crystal molecules 50a constituting the liquid crystal layer 50 are subjected to rubbing treatment in the horizontal direction in the figure, and an alignment film surface-treated to give a predetermined pretilt angle. 16 has a predetermined orientation state. Then, by applying an electric field according to the image signal, each liquid crystal molecule 50a rotates to the position shown by the broken line in the figure.

At this time, as shown in FIG. 10 (b), the liquid crystal molecules 50a constituting the liquid crystal layer 50 have a convex portion on the lower ground surface 301 of the alignment film 16 which is inclined in a direction intersecting the rubbing direction. At this inclined portion, the alignment state of the liquid crystal molecules 50a is slightly disturbed. However, since the inclination is gentle, the discontinuous surface hardly occurs in the liquid crystal layer 50.

On the other hand, as shown in 10 (c), when the lower ground surface 301 'of the alignment film 16 has a convex portion which gives a steeper inclination, the disorder of the alignment state of the liquid crystal molecules 50a becomes remarkable. However, a discontinuous surface is generated in the liquid crystal layer 50.

Therefore, as shown in the step (c) of FIG. 8 and FIG. 9 described above, the second interlayer insulating film 80 is formed by using the high density plasma CVD or the high frequency bias sputtering method. Further, if the step due to the convex portion 82 is made gentle, it is possible to reduce the alignment failure of the liquid crystal molecules 50c due to the step, which is advantageous. Further, even if the steps are the same, if the rubbing process is performed in the direction parallel to the steps, the disturbance of the alignment state of the liquid crystal molecules 50c due to the steps is reduced. Therefore, in this embodiment, the TFT array substrate 1
It is advantageous to perform a rubbing process on the alignment film 16 on the 0 side along the direction of the step due to the larger convex portion of the lattice-shaped convex portions 81 and the convex portions 82. Alternatively, as described above, it is more advantageous to perform the rubbing process only in the region where the lateral electric field is generated, along the direction of the step due to the convex portion formed in the stripe shape.

(Second Embodiment) Next, a second embodiment will be described with reference to FIGS.

The electro-optical device of the second embodiment is driven by the 1H inversion driving method (see FIG. 6) as in the first embodiment, but the electro-optical device of the first embodiment shown in FIGS. Unlike the case, for the region where the transverse electric field is hardly generated,
The formation of the convex portion 81 is omitted. On the other hand, in the region where the lateral electric field is generated, the convex portion 82 is formed as in the case of the first embodiment shown in FIG. 5, and the other configurations are the same as those of the first embodiment. That is, in the second embodiment,
A stripe-shaped convex portion 82 along the scanning line 3a is provided in the image display area 10a.

In such a structure, for example, a groove along the data line 6a is formed in at least one of the substrate 10, the base insulating film 12 and the first interlayer insulating film 4, and the storage capacitor 70 shown in FIG. The data line 6a and the data line 6a are embedded in the first interlayer insulating film 4, and the scanning line 6a and the capacitance line 3b shown in FIG.

Therefore, according to the second embodiment, the adverse effect of the lateral electric field can be efficiently reduced by the convex portion 82 formed only at the location where the lateral electric field is generated. Further, it is advantageous that the unevenness of the liquid crystal layer 50 due to the step does not occur due to the convex portion 81 that does not contribute to reducing the adverse effect of the lateral electric field.

(Third Embodiment) Next, a third embodiment will be described with reference to FIGS.

The electro-optical device of the third embodiment is driven by the 1S inversion driving method (see FIG. 7) unlike the case of the first embodiment. Therefore, unlike the case of the first embodiment shown in FIGS. 3 and 5, the formation of the convex portion 82 is omitted in the region where the lateral electric field is hardly generated. On the other hand, in the region where the lateral electric field is generated, the convex portion 81 is formed as in the case of the first embodiment shown in FIG. 4, and the other configurations are the same as those of the first embodiment. That is, in the third embodiment, the stripe-shaped convex portion 81 along the data line 6a is formed.
Are provided in the image display area 10a.

In such a structure, for example, a groove is formed along at least one of the substrate 10 and the base insulating film 12 along the scanning line 3a, the capacitance line 3b, etc., and the scanning line 3 shown in FIG.
a and the capacitance line 3b are embedded in the base insulating film 12,
Regarding the data line 6a and the storage capacitor 70 shown in FIG.
It is obtained by not embedding in such a groove. Alternatively,
The upper surface of the first interlayer insulating film 4 covering the scanning lines 3a and the capacitance lines 3b shown in FIG. 5 is flattened by CMP processing or by coating a fluid insulating film material, and the flattening is performed. The data line 6 shown in FIG. 4 on the textured surface.
It is obtained by forming a.

Therefore, according to the third embodiment, the adverse effect of the lateral electric field can be efficiently reduced by the convex portion 81 formed only at the location where the lateral electric field is generated. Further, it is advantageous that the unevenness of the liquid crystal layer 50 due to the step does not occur due to the convex portion 82 that does not contribute to reducing the adverse effect of the lateral electric field.

(Modification) In each of the above-described embodiments, the data lines 6a, the scanning lines 3a, the wirings such as the capacitance lines 3b, and the TFTs.
On the steep convex part constructed by the existence of elements such as 30
Although the second interlayer insulating film 80 is formed, as a modification, an insulating film, a conductive film, or a semiconductor is formed in a region where a convex portion is to be formed instead of or in addition to such wirings and elements. A material film for forming the protrusion may be separately formed from a film or the like.
If the convex portion is constructed from the material film for forming the convex portion in this way,
It is possible to construct a convex portion having a desired height in a desired region in terms of design, without being restricted by patterns of wiring, elements, and the like. Moreover, even if such a convex portion is formed steeply, the second interlayer insulating film 80 is formed on the convex portion by the high-density plasma CVD or the high-frequency bias sputtering method. Therefore, in the lower ground of the pixel electrode 9a, Similar to the case of each of the above-described embodiments, a convex portion having a gentle step can be obtained.

(Overall Configuration of Electro-Optical Device) The overall configuration of the electro-optical device in each of the above-described embodiments will be described with reference to FIGS. 11 and 12. Incidentally, FIG.
FIG. 12 is a plan view of the TFT array substrate 10 together with the constituent elements formed thereon as viewed from the counter substrate 20 side, and FIG. 12 is a sectional view taken along line HH ′ of FIG. 11.

In FIG. 11, the sealing material 52 is provided on the TFT array substrate 10 along the edge thereof, and is formed in parallel with the inside thereof, for example, made of the same material as or a material different from that of the above-mentioned light shielding film 23. A light shielding film 53 is provided as a frame that defines the periphery of the image display area 10a. In an area outside the sealing material 52, a data line driving circuit 101 for driving the data line 6a by supplying an image signal to the data line 6a at a predetermined timing and an external circuit connecting terminal 102 are provided along one side of the TFT array substrate 10. A scanning line driving circuit 104 that drives the scanning line 3a by supplying a scanning signal to the scanning line 3a at a predetermined timing is provided along two sides adjacent to this one side. It goes without saying that the scanning line driving circuit 104 may be provided on only one side if the delay of the scanning signal supplied to the scanning line 3a does not matter. Further, the data line driving circuits 101 may be arranged on both sides along the side of the image display area 10a. Further, on the remaining one side of the TFT array substrate 10, a plurality of wirings 105 for connecting the scanning line driving circuits 104 provided on both sides of the image display area 10a are provided. In addition, at least one corner of the counter substrate 20 is provided with a conductive material 106 for electrically connecting the TFT array substrate 10 and the counter substrate 20. Then, as shown in FIG.
Counter substrate 2 having substantially the same contour as the sealing material 52 shown in FIG.
0 is fixed to the TFT array substrate 10 by the sealing material 52.

On the TFT array substrate 10, in addition to the data line driving circuit 101, the scanning line driving circuit 104, etc., a sampling circuit for applying an image signal to a plurality of data lines 6a at a predetermined timing, Data line 6a
In addition, a precharge circuit for supplying a precharge signal of a predetermined voltage level prior to the image signal, an inspection circuit for inspecting the quality, defects, etc. of the electro-optical device during manufacturing or shipping may be formed. Good.

In each of the embodiments described above with reference to FIGS. 1 to 12, instead of providing the data line driving circuit 101 and the scanning line driving circuit 104 on the TFT array substrate 10, for example, TAB (Tape Automated Bonding). The drive LSI mounted on the substrate may be electrically and mechanically connected via an anisotropic conductive film provided in the peripheral portion of the TFT array substrate 10. Further, for example, TN (Twisted) is provided on the side on which the projection light of the counter substrate 20 is incident and on the side on which the emission light of the TFT array substrate 10 is emitted.
Nematic) mode, STN (Super Twisted Nematic) mode, VA (Vertically Aligned) mode, PDLC (P
Olymer Dispersed Liquid Crystal) mode, etc., and depending on the normally white mode / normally black mode, polarizing film, retardation film,
A polarizing plate and the like are arranged in a predetermined direction.

Since the electro-optical device according to each of the embodiments described above is applied to a projector, three electro-optical devices are used as light valves for RGB,
The light of each color separated through the dichroic mirror for RGB color separation enters each light valve as projection light. Therefore, in each embodiment, the counter substrate 20 is not provided with a color filter. However, in the predetermined area facing the pixel electrode 9a, the RGB
You may form the color filter of above with the protective film on the counter substrate 20. With this configuration, the electro-optical device according to each embodiment can be applied to a direct-view type or reflective type color electro-optical device other than the projector.

Further, in the above embodiment, Japanese Patent Laid-Open No.
No. 127,497, Japanese Patent Publication No. 3-52611,
JP-A-3-125123, JP-A-8-17110
As disclosed in Japanese Patent Publication No. 1 and the like, a light shielding film made of, for example, a refractory metal may be provided on the TFT array substrate 10 at a position facing the pixel switching TFT 30 (that is, below the TFT). . By providing a light-shielding film also on the lower side of the TFT in this way, one optical system is constructed by combining back surface reflection (return light) from the TFT array substrate 10 side and a plurality of liquid crystal devices via a prism or the like. In case,
It is possible to prevent the projected light portion or the like that passes through the prism or the like from another liquid crystal device from entering the TFT of the liquid crystal device. Further, microlenses may be formed on the counter substrate 20 so as to correspond to each pixel. Alternatively, it is also possible to form a color filter layer with a color resist or the like under the pixel electrode 9a facing the RGB on the TFT array substrate 10. By doing so, a bright electro-optical device can be realized by improving the efficiency of collecting incident light. Furthermore, a dichroic filter that creates RGB colors may be formed by utilizing interference of light by depositing a number of interference layers having different refractive indexes on the counter substrate 20. With this counter substrate with a dichroic filter, a brighter color electro-optical device can be realized.

(Electronic Device) Next, an overall configuration, particularly an optical configuration, of an embodiment of a projection type color display device as an example of an electronic device using the electro-optical device described in detail above as a light valve will be described. To do. FIG. 13 is a schematic sectional view of the projection type color display device.

In FIG. 13, a liquid crystal projector 1100 which is an example of the projection type color display device in this embodiment.
Prepares three liquid crystal modules including the liquid crystal device 100 in which the driving circuit is mounted on the TFT array substrate.
It is configured as a projector used as the B light valves 100R, 100G, and 100B. In the liquid crystal projector 1100, when the projection light is emitted from the lamp unit 1102 of the white light source such as a metal halide lamp, the three mirrors 1106 and the two dichroic mirrors 1108 cause the light components R, G corresponding to the three primary colors of RGB, It is divided into B and is led to the light valves 100R, 100G and 100B corresponding to the respective colors. At this time, in particular, the B light is
It is guided through a relay lens system 1121 including an entrance lens 1122, a relay lens 1123, and an exit lens 1124. The light components corresponding to the three primary colors modulated by the light valves 100R, 100G, and 100B are recombined by the dichroic prism 1112, and then the screen 11 via the projection lens 1114.
20 is projected as a color image.

The present invention is not limited to the above-mentioned embodiments, but can be appropriately modified within the scope of the gist or concept of the invention which can be read from the claims and the entire specification, and such modifications are accompanied. The electro-optical device, its manufacturing method, and electronic equipment are also included in the technical scope of the present invention.

[Brief description of drawings]

FIG. 1 is an equivalent circuit of various elements, wirings, and the like provided in a plurality of pixels in a matrix forming an image display area in the electro-optical device according to the first embodiment.

FIG. 2 is a plan view of a plurality of pixel groups adjacent to each other on a TFT array substrate on which data lines, scanning lines, pixel electrodes and the like are formed in the electro-optical device according to the first embodiment.

3 is a cross-sectional view taken along the line AA ′ of FIG.

FIG. 4 is a sectional view taken along line BB ′ of FIG.

5 is a cross-sectional view taken along the line CC ′ of FIG.

FIG. 6 is a schematic plan view of a pixel electrode showing a voltage polarity and a region where a lateral electric field is generated in each electrode in the 1H inversion driving method used in the embodiment.

FIG. 7 is a schematic plan view of a pixel electrode showing a voltage polarity and a region where a lateral electric field is generated in each electrode in the 1S inversion driving method which can be adopted in the embodiment.

8A to 8C are process diagrams sequentially showing a manufacturing process of the electro-optical device according to the embodiment with respect to a portion corresponding to the BB ′ cross section in FIG. 2.

9A to 9C are process diagrams sequentially showing a manufacturing process of the electro-optical device according to the embodiment with respect to a portion corresponding to the CC ′ section in FIG. 2.

FIG. 10 is a schematic side view showing a relationship between an inclination of a step due to a convex portion and an alignment state of liquid crystal molecules in the electro-optical device according to the embodiment.

FIG. 11 is a plan view of the TFT array substrate in the electro-optical device according to each of the embodiments, together with the respective components formed thereon, as viewed from the counter substrate side.

12 is a cross-sectional view taken along the line HH 'of FIG.

FIG. 13 is a schematic cross-sectional view showing a color liquid crystal projector which is an example of a projection type color display device which is an embodiment of an electronic apparatus of the invention.

[Explanation of symbols]

1a ... semiconductor layer 1a '... Channel area 1b ... Low concentration source region 1c ... low concentration drain region 1d ... High-concentration source region 1e ... high-concentration drain region 1f ... Pixel potential side capacitance electrode 2 ... Insulating film 3a ... scanning line 3b ... Capacity line 4 ... First interlayer insulating film 5 ... Contact hole 6a ... Data line 8 ... Contact hole 9a ... Pixel electrode 10 ... TFT array substrate 12 ... Base insulating film 16 ... Alignment film 20 ... Counter substrate 21 ... Counter electrode 22 ... Alignment film 23 ... Shading film 30 ... TFT 50 ... Liquid crystal layer 50a ... Liquid crystal molecule 70 ... Storage capacity 80 ... Second interlayer insulating film 81, 82 ... convex portion C1, C2 ... Horizontal electric field generation region

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01L 29/786 H01L 29/78 619A F term (reference) 2H090 HA04 HA07 HB03 HC19 HD01 2H092 GA17 JA24 JB24 JB33 JB57 JB58 KA07 KA12 KB25 MA05 MA07 NA04 PA06 RA05 5C094 AA06 BA03 BA43 CA19 DA14 DA15 DB04 EA04 EA07 HA10 5F058 BA20 BB06 BD02 BD04 BD07 BD10 BF03 BF04 BF09 BF12 BB27 DD12 FF12 DD12FF23 DD12DD23 DD23 FF02 DD13 DD021413 DD02 DD14 DD021414 GG13 GG24 GG47 HJ23 HL03 HL05 HL23 HM15 NN03 NN22 NN23 NN24 NN25 NN26 NN34 NN35 NN72 NN73 PP10 QQ17

Claims (12)

[Claims] 1. A first pixel electrode group for inversion driving in a first cycle and an electro-optical material sandwiched between a pair of first and second substrates, and a first pixel electrode group complementary to the first pixel electrode group. A plurality of pixel electrodes including a second pixel electrode group to be invertedly driven in a second cycle are arranged in a plane on the first substrate and are opposed electrodes facing the plurality of pixel electrodes on the second substrate. An electro-optical device manufacturing method for manufacturing an electro-optical device comprising: a step of forming a pattern including wiring and elements for driving the pixel electrode on the first substrate; High density plasma CVD (Chemical Vap
or Deposition) or a high frequency bias sputtering method, and a step of forming an interlayer insulating film, and a step of forming the plurality of pixel electrodes after forming the interlayer insulating film. 2. The method further comprises the step of forming a material film for forming the convex portion separately from the pattern, wherein the convex portion is at least partially formed by the presence of the material film instead of or in addition to the pattern. The electro-optical device manufacturing method according to claim 1, wherein the electro-optical device is manufactured in a similar manner. 3. The method further comprises the step of digging a groove having a predetermined pattern on the first substrate, wherein the convex portion is at least partially constructed by the existence of the groove instead of or in addition to the pattern. The method of manufacturing an electro-optical device according to claim 1, wherein 4. The method further comprises: a step of forming another interlayer insulating film on the first substrate; and a step of digging a groove having a predetermined pattern on the other interlayer insulating film, wherein the convex portion is formed of: 3. The method for manufacturing an electro-optical device according to claim 1, wherein the groove is at least partially constructed by the presence of the groove instead of or in addition to the pattern. 5. The CMP (Che (Che) is performed on the surface of the laminate on the substrate before the step of forming the pattern is completed.
mical mechanical polishing) is further provided, and the convex portion is at least partially constructed by the pattern formed on the surface subjected to the CMP treatment. Claim 1
5. The method for manufacturing an electro-optical device according to any one of items 1 to 4. 6. The convex portion extends in a second direction that intersects the first direction in a region that is a gap between the pixel electrode and a first region along a first direction in a region that is a gap between the pixel electrodes. The method for manufacturing an electro-optical device according to claim 1, wherein the method is constructed in only one of the second region and the second region. 7. The electro-optical device according to claim 6, wherein the convex portion is constructed with a gap between adjacent pixel electrodes that are inverted and driven with different polarities as the one region. Production method. 8. Before the step of forming the interlayer insulating film,
8. The electro-optical device according to claim 6, further comprising the step of forming another wiring or element that drives the pixel electrode in the other region of the first region and the second region. Device manufacturing method. 9. The manufacturing of the electro-optical device according to claim 1, wherein the protrusions are constructed in a lattice shape along a region serving as a gap between the pixel electrodes. Method. 10. The element for driving the pixel electrode formed on the first substrate is a bonded SOI (Silicon On In)
10. The method for manufacturing an electro-optical device according to claim 1, further comprising a single crystal semiconductor layer formed by a (sulator). 11. A first pixel electrode group for inversion driving in a first cycle on the first substrate, wherein an electro-optical material is sandwiched between a pair of first and second substrates, and A plurality of pixel electrodes that are arranged in a plane and include a second pixel electrode group for inversion driving in a second period that is complementary to the first period, and a pattern that includes wirings and elements that drive the pixel electrodes A high density on the lower side of the pixel electrode, which is on the upper side of the convex portion at least partially constructed by the presence of the pattern in a region which becomes a gap between the pixel electrodes adjacent to each other in a plan view during the manufacturing process. An interlayer insulating film which is formed by plasma CVD or a high frequency bias sputtering method and has a step on the surface that is gentler than the step on the surface of the protrusion, and faces the plurality of pixel electrodes on the second substrate. Electrodes Electro-optical device, characterized in that was e. 12. An electronic apparatus comprising the electro-optical device according to claim 11.