JPH0830812B2 - Semiconductor device and method for forming spacer thereof - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a spacer for a semiconductor device, such as a liquid crystal display device or a solid-state imaging device, in which two substrates have a sandwich structure with a resin interposed therebetween. And a semiconductor device.

2. Description of the Related Art FIG. 6 shows a sectional view of a panel of an active matrix type liquid crystal display device as a first conventional example. TFT (thin film transistor) substrate 1a in which switching elements and pixel electrodes are arranged in an XY matrix and counter transparent substrate 2a in which a common electrode is formed
Is configured so that a constant gap is maintained by a spacer material 3 such as beads or glass fibers, the liquid crystal 4 is injected into the facing space, and the periphery is sealed with a seal material 5a.

The outline of the assembling process of this liquid crystal display device will be described below with reference to FIG.

Generally, an alignment film 6 made of an organic thin film of polyimide or the like is formed on the facing inner surfaces of the TFT substrate 1a and the counter substrate 2a by a printing method or the like, and a rubbing treatment is performed to control the alignment (FIG. 7 (a)). . Next, after the sealing material 5a is formed in the peripheral area of the TFT substrate 1a or the counter substrate 2a by a printing method or the like (FIG. 7 (b)), the pixel areas A, B, C, D (eighth area) are formed.
Spacer beads 3a are dispersed in order to control the gap between the TFT substrate 1a and the counter substrate 2a to be constant, and the TFT substrate 1a and the counter substrate 2a are bonded to each other. Then, the liquid crystal 4 is injected into the opposed space between the TFT substrate 1a and the opposed substrate 2a, and the liquid crystal injection port is sealed with resin. Further, polarizing plates 7 are attached to the substrates 1a and 2a, respectively, and driving ICs are mounted on the periphery to complete the process (FIG. 7 (d)).

Next, a second conventional example will be described below with reference to FIG. The second conventional example does not disperse the beads as a spacer as described in the first conventional example, but a few microns in advance on the surface of the TFT substrate 1a or the counter substrate 2a by a printing method. A spacer having a height of 1 is formed from a resin, and after orientation processing is performed, the two substrates 1a and 1b are bonded together.

That is, in the printing method, first, the TFT substrate 1a and the counter substrate 2a
The third such as a metal mask with a predetermined hole 8 on the surface of
The substrate 9 is placed, and after alignment, it is fixed (FIG. 9 (a)). Next, the resin 5 is filled in the holes 8 from above the third substrate 9 (FIG. 9 (b)). Next, the third substrate 9 is removed, and the resin remaining on the first substrates 1a and 2a is cured by, for example, heat treatment to form spacers 10 (FIG. 9 (c)).

Next, a third conventional example will be described below with reference to FIG.
The third conventional example does not disperse the beads as the spacer as described in the first conventional example, but the pixels other than the pixel portion are previously formed on the surfaces of the TFT substrate 1a and the counter substrate 2a by a photolithography process of semiconductor manufacturing. A spacer having a height of several microns is formed of a resin at an arbitrary position in (1), and after orientation processing is performed, the two substrates are bonded together. A conventional example using a photocurable resin is shown below.

In the photolithography process, first, the film thickness of the resin 5 is controlled and applied uniformly on the surfaces of the TFT substrate 1a and the counter substrate 2a so that the gap obtained by bonding the first and second substrates becomes a predetermined value (Fig. 10). (A)). Next, using the third substrate 9 having the light-shielding portion 11 as a mask, the third substrate 9 is arranged on the surface of the resin 5 for exposure (first
Next, the third substrate is removed and the unreacted resin is removed by development to form the spacer 10 (FIG. 10 (c)).

As a fourth conventional example, a sectional view of a color solid-state imaging device is shown.
Shown in Figure 11. The second substrate 2b on which the solid-state image pickup device 1b and, for example, a color filter are formed, includes a pixel portion of the device and, for example, R,
A second solid-state image sensor 1b and, for example, a color filter formed by aligning the G and B color filters.
All (FIG. 11 (a)) or part (FIG. 11 (b)) of the gaps between the substrates 2b are bonded via the adhesive resin 5b. The space between the solid-state image pickup device 1b and the second substrate 2b on which, for example, a color filter is formed is controlled by the adhesive resin layer.

In the above-mentioned first, second, third, and fourth conventional examples, two substrates are all bonded uniformly with a constant gap.

Problems to be Solved by the Invention In the first conventional example, the gap between the two substrates is controlled by using spacer beads in the assembly process. However, in the bead dispersion method, the spacers are uniformly dispersed in the screen area, or It is difficult to selectively dispose at any place other than the pixel portion.

Further, in the second conventional example, the protrusions that serve as spacers are selectively provided at arbitrary locations by using the printing method, but the alignment accuracy is poor, and the spacer height depends on the thickness of the third substrate that serves as a mask. When the thickness of the third substrate is several microns, the third substrate is easily deformed and it is difficult to obtain a spacer having a uniform height in a large area.

On the other hand, in the third and fourth conventional examples, a protrusion serving as a spacer is selectively provided at an arbitrary position by using a photolithography process of semiconductor manufacturing, which allows fine processing, but has a large number of processes and also has a disadvantage in exposure. Due to problems, there are limits to large substrates.

In view of the above problems, it is an object of the present invention to provide a semiconductor device having a uniform spacer thickness and good productivity, and a manufacturing method thereof.

Means for Solving the Problems To solve the above problems, the present invention uses a spacer material formed by encapsulating a resin in a microcapsule.
After pressing the third substrate in the form of a stamp having a groove corresponding to the spacer shape to be formed through the spacer material by pressure bonding and subjecting the spacer to solidification treatment by heat or light, The substrate is removed and the microcapsules and capsules that are destroyed by pressure bonding are used to wash and remove the resin that has overflowed.

Effect According to the spacer forming method of the present invention, when forming a pattern at an arbitrary position, a photolithography process is not used, and a very simple technique of press-bonding a substrate to be a die and heat or light treatment to a spacer material is used to obtain a uniform pattern. Spacers can be formed.

Example Hereinafter, a method for forming a spacer of a semiconductor device will be described as an example of the present invention with reference to the drawings.

The spacer forming method of the first embodiment will be described below with reference to FIG.

First, the first substrate 1, in this embodiment, a bus wiring group for transmitting a scanning signal and a display signal is arranged in an XY matrix, and a switching element (TFT) is provided at the intersection of the matrix. Resin 5 in capsule 12
The spacer material 3 (see FIG. 2) in which is encapsulated is uniformly dispersed, and the spacer material 3 is fixedly arranged on the substrate 1 by heat treatment (FIG. 1 (a)). Next, a pressing die-shaped third substrate 9 formed by forming a plurality of grooves 13 having a width, height, and shape corresponding to the shape of the spacer to be formed is placed on the first substrate 1 via the spacer material 3. Crimping is performed (Fig. 1 (b)). The microcapsules 12 of the spacer material 3 protruding from the groove 13 by pressure bonding are crushed and destroyed. After that, the spacer material housed in the groove and the resin protruding due to the destruction of the microcapsules are cured by irradiation with ultraviolet light (FIG. 1 (c)). At this time, if a resin having a different photoreaction rate due to contact with oxygen is encapsulated in the microcapsule, a reaction time difference occurs between the resin protruding due to the destruction and the resin in the microcapsule. Next, the third substrate 9 is removed, and by utilizing the characteristic that the reaction time of the resin changes depending on the environment, the microcapsules 12 destroyed by pressure bonding and the resin protruding from the microcapsules 12 are washed and removed. The spacer 10 is formed by the spacer material 3 which is located in the groove 13 and is not destroyed (FIG. 1 (d)).

After that, as shown in the conventional example (FIGS. 7 (c) and 7 (d)), the counter electrode 2a is provided via the spacer 10, the liquid crystal 4 is injected into the counter space, and the periphery thereof is sealed with a sealing material.
By sealing with 5a, an active matrix type liquid crystal display element can be constructed.

Next, a second embodiment of the spacer forming method for a semiconductor device according to the present invention will be described below with reference to FIG. In the second embodiment, the light shielding portion 11 is provided in the contact portion other than the groove of the third substrate 9, and the spacer material 3 is fixed to the third substrate 9 as in the first embodiment. After pressure bonding to the substrate 1, the spacer material housed in the groove is cured by light irradiation (FIG. 3 (a)).
-(C)). Next, the third substrate is removed, and among the microcapsules 12 and the resin protruding from the microcapsules 12 which are destroyed by pressure bonding, unreacted ones are washed and removed (FIG. 3 (d)). The resin in this case has a high photoreactivity. As an example of the present embodiment, when the first substrate is a solid-state image sensor, the second substrate functioning as a color filter is formed on the first substrate 1 having the spacer 10 as described above, for example, 10 Adhere as shown in Figures (a) and (b).

Next, a third embodiment of the spacer forming method for a semiconductor device according to the present invention will be described below with reference to FIG. In the third embodiment, the light shielding portion 11 made of, for example, Cr formed on the first substrate 1 is used.
So that the spacer material 3 remains on the first and third substrates 1,
9 is aligned and crimped (Fig. 4 (a),
(B)). Next, the resin 5 protruding from the back surface of the first substrate 1 by light irradiation and pressure bonding is photolyzed (FIG. 4 (b)), the third substrate 9 is removed, and the photolyzed resin is washed. It is removed (Fig. 4 (c)). Next, the spacer material 3 that remains is cured by heat treatment or re-irradiation with light having different intensity or wavelength to form the spacer 10 (FIG. 4 (c)).

The spacer 10 thus formed is used for the third substrate 9
The height of the spacer 10 can be controlled by the depth of the groove 13 and the spacers having different heights can be collectively formed (FIG. 5 (a)). Also, the spacer size can be controlled in advance depending on the size of the microcapsule 12 (FIG. 5 (b)). The spacer 10 may be formed in a stripe shape, a zigzag shape, or a column shape, depending on whether the first substrate is a TFT or a solid-state image sensor.

EFFECTS OF THE INVENTION According to the method of the present invention, in forming a fine pattern at an arbitrary place, a spacer can be formed by an extremely simple method without using a photolithography process, and therefore, it is also promising for a large substrate. Further, in the spacers formed as described above, the height of the spacers can be controlled by the groove depth of the third substrate, and the spacers having different heights can be collectively formed. Also, the spacer size can be controlled in advance depending on the size of the microcapsules. Further, the reactive resin is generally put in a bottle and stored in a cool and dark place, but it changes with time by touching air or returning to room temperature each time it is used, whereas the spacer material of the present invention is Since it is protected by microcapsules, it is possible to improve storage stability.

[Brief description of drawings]

FIG. 1 is a process diagram showing a spacer forming method utilizing a photoreaction rate as a first embodiment of the spacer forming method of the present invention, FIG. 2 is a sectional view of a spacer material of the present invention, and FIG. FIG. 5A, FIG. 5B are process diagrams showing a spacer forming method using a light-shielding mask as an example, FIG. 4 is a process diagram showing a spacer forming method using a photolytic resin as a third example. ) Is a cross-sectional view of spacers having different sizes formed by the forming method of the present invention, FIG. 6 is a cross-sectional view of a liquid crystal display device using spacer beads as a first conventional example,
FIG. 7 is an assembly process drawing thereof, FIG. 8 is a schematic plan sectional view of a liquid crystal display device, and FIG. 9 is a second conventional example of an assembly process drawing of a liquid crystal display device in which a spacer is formed by using a resin by a printing method. 10 is an assembly process diagram of a liquid crystal display device using a resin by a photolithography process as a third conventional example, and FIG.
It is an assembly process drawing of the solid-state imaging device which used the resin layer for adhesion as space control. 1 ... First substrate, 3 ... Spacer material, 9 ... Third substrate, 10 ... Spacer, 11 ... Light shielding part, 12 ... Microcapsule, 13 ... Groove.

Claims (4)

[Claims] 1. A semiconductor device in which two substrates, a first substrate and a second substrate, have a sandwich structure with a resin layer interposed therebetween, wherein a spacer provided between the substrates for controlling the resin layer to have a constant thickness has a microstructure. A semiconductor device comprising a spacer material formed by encapsulating resin. 2. A spacer material comprising a thermo-reactive or photo-reactive or heat- and photo-reactive resin encapsulated in microcapsules. 3. The spacer material according to claim 2, wherein the photoreactive resin is a photocurable type or a photodegradable type. 4. A step of dispersing a spacer material on the surface of the first substrate, and a depth corresponding to the spacer to be formed,
A step of pressure-bonding a third substrate having grooves of width, shape, etc. to the first substrate through the dispersed spacer material; a step of solidifying the spacer material by heat or light; 3. The method for forming a spacer of a semiconductor device, comprising the steps of removing the substrate of 3 and then washing and removing the microcapsules of the spacer material and the resin in the microcapsules that have been destroyed by pressure bonding.