JP2005051105A - Method of manufacturing semiconductor device and electro-optical device, and electronic apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form a contact hole capable of making an interlayer connection surely without causing damage to a board. <P>SOLUTION: Pillar-shaped mask materials 71a and 71b are formed of resist or the like at positions where contact holes are formed, and an insulating film 32 is formed by application on all the surface of the board except the vicinities of the mask materials 71a and 71b or the mask materials 71a and 71b. Thereafter, the mask materials 71a and 71b are removed through a peeling method or the like, and holes 32a and 32b produced through a peeling process are used as the contact holes. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a semiconductor device, a method for manufacturing an electro-optical device, and a semiconductor device manufactured thereby and an electronic apparatus including the electro-optical device, and more particularly to a technique for forming a contact hole for connecting layers. .

  In recent years, in an electronic device such as a semiconductor device or an electro-optical device, wiring is multilayered to increase the degree of integration. In a device having such a multilayer wiring structure, a contact hole (opening) is formed in the interlayer insulating film in order to establish conduction between the wiring layers stacked via the interlayer insulating film.

For example, in the field of electro-optical devices, pixel switching TFTs, signal lines, and pixel electrodes formed in multiple layers have been developed (see Patent Document 1). In this structure, for example, a TFT is disposed in the lowermost layer portion of the substrate, and a signal line is disposed thereon via a first interlayer insulating film. Further, a second interlayer insulating film that covers the signal line and the first interlayer insulating film is further provided on the substrate, and a pixel electrode is disposed thereon. In order to establish conduction between these layers, the source region of the TFT is connected to the signal line through the first contact hole penetrating the gate insulating film and the first interlayer insulating film, and the drain region is connected to the gate insulating film, The pixel electrode is connected through a second contact hole penetrating the first interlayer insulating film and the second interlayer insulating film.
Conventionally, dry etching has been used in the process of forming such contact holes.
Japanese Patent No. 2625268

  However, when the contact hole is formed by etching, the electrical characteristics of the resulting device may vary due to the non-uniformity of the film thickness of the interlayer insulating film in which the contact hole is formed. For example, since over-etching occurs where the film thickness is small, the shape of the contact hole is enlarged, or the lower wiring layer is thinned. In particular, in the case of dry etching, since the etching selectivity between the insulating material and the conductive material cannot be sufficiently ensured, the degree of thinning increases. Such thinning of the lower wiring layer leads to increased contact resistance and non-ohmic conduction characteristics, and sometimes causes poor conduction, and the expansion of the contact hole shape increases leakage current between adjacent conductive layers. Cause short circuit failure. Further, where the film thickness is thick, insufficient conduction causes a conduction failure.

In the etching process described above, plasma etching is often performed. In this case, plasma damage may occur on the substrate, and the electrical characteristics of the device may be deteriorated. In addition, since a reaction product is generated in plasma etching, the product adheres to the bottom and side walls of the contact hole, which causes a conduction failure.
These problems become serious when the number of wiring layers increases and the distance between wiring layers for connection increases.

  Further, in the multi-layered device as described above, the contacts disposed between the wiring layers are increased as the distance between the wiring layers to be connected becomes wider (that is, the number of interlayer insulating films disposed between the layers increases). The aspect ratio of the hole becomes large, and it becomes difficult to form this in a single process. For this reason, conventionally, a relay electrode is provided between these wiring layers, and the lower wiring layer and the relay electrode and the relay electrode and the upper wiring layer are connected by separate contact holes. (See Patent Document 1 above). However, in this method, the degree of integration is reduced by forming the relay electrode, which hinders high performance of the device. Further, in an electro-optical device such as a liquid crystal device, when such a relay electrode is formed, the aperture ratio of the pixel is lowered accordingly.

  The present invention has been made to solve the above-described problems, and a method for manufacturing a semiconductor device and a method for manufacturing an electro-optical device capable of reliably conducting conduction between layers without impairing device performance. It is another object of the present invention to provide an electronic apparatus including a semiconductor device or an electro-optical device manufactured by this method.

  In order to achieve the above object, a method for manufacturing a semiconductor device according to the present invention is a method for manufacturing a semiconductor device having a semiconductor layer and a conductive layer stacked via an insulating film, the semiconductor layer being formed on a substrate. A step of forming, an insulating film having an opening at a predetermined position on the semiconductor layer, and a conductive layer electrically connected to the semiconductor layer through the opening on the insulating film. A step of forming a mask material at the predetermined position on the semiconductor layer, a step of forming an insulating film on the entire surface of the substrate excluding the mask material, and the mask material. And a step of forming an opening in the insulating film.

That is, in this method, a columnar mask material is formed on the first wiring layer in advance before the formation of the interlayer insulating film, and this is removed using a peeling solution or the like after the formation of the interlayer insulating film. And the hole produced by this is used as a contact hole. Therefore, unlike the conventional method using dry etching, the substrate is not damaged. In particular, in this method, even if the interval between the layers to be connected becomes wide, it can be dealt with by simply changing the height (film thickness) of the mask material. There is no inconvenience such as increased damage.
Further, as a method for removing the mask material, a method in which the semiconductor layer is not etched at all can be selected, so that a sufficient time can be taken for removing the mask material. For this reason, the mask material can be removed reliably, and at the same time, the shape of the contact hole is not impaired and the semiconductor layer is not thinned.

  In the case where a plurality of insulating films are disposed between the semiconductor layer and the conductive layer, the mask material forming step, the insulating film forming step, and the mask material removing step in the insulating film forming step. By repeating the above, it is possible to form an opening that penetrates the plurality of insulating films in the thickness direction. Thereby, even when the interval between the semiconductor layer and the conductive layer is widened, they can be reliably connected without damaging the substrate.

  By the way, in the above-described method, one or more insulating films disposed between the semiconductor layer and the conductive layer are all opened by forming / removing the mask material. However, when the interval between the layers to be connected is small, for example, when there is only one insulating film disposed between the layers, even if the conventional etching method is used, the substrate is caused by this. Damage and device characteristic degradation may be tolerated. In addition, the presence of the mask material at the time of forming the insulating film may cause a problem in controlling the film quality of the insulating film and the interface state between the insulating film and the lower layer film. It is desirable to form. That is, when a plurality of interlayer insulating films are arranged between the semiconductor layer and the conductive layer, a method such as etching one layer or a plurality of interlayer insulating films (first insulating films) close to the semiconductor layer Even if the other interlayer insulating film (second insulating film) is opened by forming / removing the mask material, the object of the present invention can be sufficiently achieved. For this reason, in the present invention, the semiconductor device may be manufactured by the following method.

That is, a method for manufacturing a semiconductor device according to the present invention is a method for manufacturing a semiconductor device having a semiconductor layer and a conductive layer stacked via an insulating film, the step of forming a semiconductor layer on a substrate, and the semiconductor Forming the insulating film having an opening at a predetermined position on the layer; and forming a conductive layer conducting through the opening on the insulating film, the insulating film forming step Forming a first insulating film having an opening at the predetermined position on the semiconductor layer, and covering the inside of the opening at the predetermined position on the substrate. A step of forming a mask material projecting upward, a step of forming a second insulating film on the entire surface of the substrate excluding the mask material, and removing the mask material, the thickness of the second insulating film is increased. Penetrating in the direction and communicating with the opening of the first insulating film Characterized by a step of forming an opening.
Thus, by dividing the insulating film disposed between the layers into a first insulating film and a second insulating film and independently selecting the opening method of these insulating films, the degree of freedom of the process can be increased. .

  As a specific form of the first insulating film forming step, the first insulating film forming step includes a step of forming a mask material on the semiconductor layer and an entire surface of the substrate excluding the mask material. As an example, an insulating film can be formed, and a process of forming an opening in the insulating film by removing the mask material can be given.

  Further, in this method, when the second insulating film is composed of a plurality of insulating films (that is, when a plurality of insulating films are disposed between the semiconductor layer and the conductive layer), the insulating film In the forming process, after the first insulating film forming process, by repeating the mask material forming process, the second insulating film forming process, and the mask material removing process in the opening of the first insulating film, An opening that communicates with a plurality of insulating films disposed between the semiconductor layer and the conductive layer can be formed. Thereby, even when the interval between the semiconductor layer and the conductive layer is widened, they can be reliably connected while sufficiently suppressing damage to the substrate.

  The electro-optical device manufacturing method of the present invention is a method for manufacturing an electro-optical device having a semiconductor layer and a pixel electrode stacked via an insulating film, the step of forming a semiconductor layer on a substrate, A step of forming an insulating film having an opening at a predetermined position on the semiconductor layer; and a step of forming a pixel electrode conducting through the opening on the insulating film. The forming step includes forming a mask material at the predetermined position on the substrate, forming an insulating film on the entire surface of the substrate excluding the mask material, and removing the mask material to form the insulating film on the insulating film. And a step of forming an opening.

  Even in this method, since the hole generated in the interlayer insulating film due to the removal of the mask material is used as a contact hole, unlike the conventional method using etching, the substrate is not damaged in the contact hole forming process. Absent. In particular, in this method, even if the interval between the layers to be connected becomes wide, it can be dealt with by simply changing the height (film thickness) of the mask material. There is no inconvenience such as increased damage. In addition, in this method, since an opening with a large aspect ratio can be formed, it is not necessary to form a relay electrode as in the prior art. For this reason, it becomes possible to form a bright display device having a high aperture ratio.

Note that in the case where a plurality of insulating films are arranged between the semiconductor layer and the pixel electrode, in the insulating film forming process, the mask material forming process, the insulating film forming process, and the mask material removing process are performed. By repeating the above, it is possible to form an opening that penetrates the plurality of insulating films in the thickness direction. Thereby, even when the interval between the semiconductor layer and the pixel electrode is widened, the layers can be reliably connected without damaging the substrate.
In the above-described method, one or more insulating films disposed between the semiconductor layer and the pixel electrode are opened by forming / removing the mask material. However, as described above, some insulating films are formed. Even if the film (that is, one or a plurality of insulating films close to the semiconductor layer; the first insulating film) is opened by a method such as etching, damage to the substrate may be allowed. For this reason, in the present invention, the electro-optical device may be manufactured by the following method.

That is, the method for manufacturing an electro-optical device according to the present invention is a method for manufacturing an electro-optical device having a semiconductor layer and a pixel electrode stacked via an insulating film, the step of forming a semiconductor layer on a substrate, A step of forming an insulating film having an opening at a predetermined position on the semiconductor layer; and a step of forming a pixel electrode conducting through the opening on the insulating film. The forming step includes forming a first insulating film having an opening at the predetermined position on the semiconductor layer, and covering the inside of the opening at the predetermined position on the substrate. A step of forming a mask material projecting on the insulating film; a step of forming a second insulating film on the entire surface of the substrate excluding the mask material; and removing the mask material to thereby form the second insulating film. Through the thickness direction and the opening of the first insulating film Characterized by a step of forming an opening communicating.
Thus, by dividing the insulating film disposed between the layers into a first insulating film and a second insulating film and independently selecting the opening method of these insulating films, the degree of freedom of the process can be increased. .

  As a specific form of the first insulating film forming step, the first insulating film forming step includes a step of forming a mask material on the semiconductor layer and an entire surface of the substrate excluding the mask material. As an example, an insulating film can be formed, and a process of forming an opening in the insulating film by removing the mask material can be given.

  In this method, when the second insulating film is composed of a plurality of insulating films (that is, when a plurality of insulating films are arranged between the semiconductor layer and the pixel electrode), the insulating film In the forming step, after the first insulating film forming step, the mask material forming step, the second insulating film forming step, and the mask material removing step are repeated, whereby the gap between the semiconductor layer and the pixel electrode is repeated. An opening that communicates with a plurality of layers of insulating films disposed on the substrate can be formed. As a result, even when the distance between the semiconductor layer and the pixel electrode is widened, they can be reliably connected while sufficiently suppressing damage to the substrate.

  The above-described mask material forming method may be any method as long as it can form a columnar structure on the substrate. The mask material used may be either an inorganic material or an organic material, or a mixed material thereof. However, if the mask material is an organic material, it is more preferable because it can be easily formed using a coating method. Specifically, in the step of forming the mask material, a photosensitive resin is formed on the entire surface of the substrate, and this is exposed and developed, and the mask material is patterned at the position where the opening is to be formed. A columnar structure can be most easily obtained. Further, when the mask material is made of a photosensitive resin as described above, the effect of the present invention is more easily exerted by using a stripping solution or the like because it can be easily removed without damaging the substrate.

  Further, when the mask material is an organic material, the mask material can be formed by a droplet discharge method using a quantitative discharge device such as a printer head of an ink jet printer. That is, in the step of forming the mask material, the mask material may be formed by selectively discharging a liquid material to a position where the opening is to be formed and solidifying the liquid material. In the droplet discharge method, since the material can be supplied only to a necessary portion, the use efficiency of the material is higher than that of other application methods, which is advantageous in terms of cost.

  As other methods for forming the mask material by coating, other known methods such as spin coating, dip coating, roll coating, curtain coating, and spraying can be used. Since each of these methods has advantages and disadvantages, it is desirable to use them properly depending on the form of the contact hole (opening) to be formed. For example, in the spin coating method, the uniformity of the film thickness is high and the control of the film thickness is relatively easy, but there is a difficulty in terms of material utilization efficiency. On the other hand, in the droplet discharge method, although the material utilization efficiency is high, it is difficult to make a columnar structure with a high aspect ratio. For this reason, in the mask material forming step, it is preferable to select a mask material forming method according to the depth of the contact hole, for example, the number of interlayer insulating films through which the contact hole penetrates. For example, if the number of layers is one, a droplet discharge method may be used. If there are a plurality of layers, a thick photosensitive resin is formed on the entire surface of the substrate using a method such as a spin coating method, and exposure is performed. This may be patterned by development.

  According to another aspect of the invention, there is provided an electronic apparatus including a semiconductor device or an electro-optical device manufactured using the above-described method. Thereby, it is possible to provide an electronic device having excellent electrical characteristics. In addition, by providing the display unit with the above-described electro-optical device, it is possible to increase display brightness and reduce power consumption.

Embodiments according to the present invention will be described below with reference to the drawings.
[First Embodiment]
FIG. 1 is a plan view of a liquid crystal display device according to an embodiment of the electro-optical device of the present invention viewed from the counter substrate side together with each component, and FIG. 2 is a cross-sectional view taken along the line HH ′ of FIG. It is. FIG. 3 is an equivalent circuit diagram of various elements and wirings in a plurality of pixels formed in a matrix in the image display region of the liquid crystal display device.
In each drawing used in the following description, the scale is different for each layer and each member so that each layer and each member can be recognized on the drawing.

  As shown in FIGS. 1 and 2, in the liquid crystal display device 100 of this embodiment, the TFT array substrate 10 and the counter substrate 20 are bonded together by a sealing material 52, and the liquid crystal 40 is formed in a region partitioned by the sealing material 52. Is enclosed and retained. The sealing material 52 is formed with a liquid crystal injection port 55 for injecting liquid crystal after the TFT array substrate 10 and the counter substrate 20 are bonded together at the time of manufacturing. The liquid crystal injection port 55 is sealed after the liquid crystal injection. It is sealed with a material 54. A counter electrode (common electrode) 24 is formed on the inner surface side of the counter substrate 20, and a pixel electrode 14 is formed on the inner surface side of the TFT array substrate 10.

  A peripheral part (not shown) made of a light-shielding material is formed in a region inside the sealing material 52, while a data line driving circuit 201 and a mounting terminal 202 are provided in the TFT array substrate in a region outside the sealing material 52. The scanning line driving circuit 204 is formed along two sides adjacent to the one side. On the remaining side of the TFT array substrate 10, a plurality of wirings 205 are provided for connecting between the scanning line driving circuits 204 provided on both sides of the image display area. Further, at least one corner of the counter substrate 20 is provided with an inter-substrate conductive material 206 for establishing electrical continuity between the TFT array substrate 10 and the counter substrate 20.

  In the liquid crystal display device 100, the type of liquid crystal 40 to be used, that is, an operation mode such as a TN (Twisted Nematic) mode, an STN (Super Twisted Nematic) mode, a VAN (Vertical Alignment Nematic) mode, a normally white mode / Depending on the normally black mode, a retardation plate, a polarizing plate and the like are arranged in a predetermined direction, but the illustration is omitted here. Further, in the case where the liquid crystal display device 100 is configured for color display, for example, red (R), green (G), blue (in the region facing the pixel electrodes 14 of the TFT array substrate 10 in the counter substrate 20. The color filter of B) is formed together with the protective film.

  In the image display region of the liquid crystal display device 100 having such a structure, as shown in FIG. 3, a plurality of pixels 100a are configured in a matrix, and each of these pixels 100a has a pixel switching region. , Here a TFT (Thin Film Transistor) 30 is formed, and a signal line 34 for supplying pixel signals S 1, S 2,..., Sn is electrically connected to the source of the TFT 30. The pixel signals S1, S2,..., Sn to be written to the signal line 34 may be supplied line-sequentially in this order, or may be supplied for each group to a plurality of adjacent signal lines 34. . Further, the scanning line 33 is electrically connected to the gate of the TFT 30, and the scanning signals G1, G2,..., Gm are applied to the scanning line 33 in a pulse-sequential manner in this order at a predetermined timing. It is configured.

  The pixel electrode 14 is electrically connected to the drain of the TFT 30, and the pixel signals S 1, S 2,... Sn supplied from the signal line 34 are obtained by turning on the TFT 30 as a switching element for a certain period. Write to each pixel at a predetermined timing. The pixel signals S1, S2,..., Sn written in the liquid crystal via the pixel electrode 14 in this way are held for a certain period with the counter electrode 24 of the counter substrate 20 shown in FIG. In order to prevent the held pixel signals S1, S2,..., Sn from leaking, a holding capacitor 60 is added in parallel with the liquid crystal capacitor formed between the pixel electrode 14 and the counter electrode. For example, the voltage of the pixel electrode 14 is held by the holding capacitor 60 for a time that is three orders of magnitude longer than the time when the source voltage is applied. Thereby, the charge retention characteristics are improved, and the liquid crystal display device 100 with a high contrast ratio can be realized.

Next, the configuration of the main part of the liquid crystal display device 100 will be described. FIG. 4 is a schematic diagram illustrating an enlarged pixel portion of the TFT array substrate 10.
The TFT 30 of this embodiment has a top gate type structure, and a semiconductor film 31, a gate insulating film 32, and a gate electrode 33a are stacked in this order from the lower layer side of the substrate 10A serving as a main body. That is, a gate insulating film 32 is provided on the semiconductor film 31 provided in an island shape on the base insulating film 11 so as to cover the entire surface of the substrate, and is opposed to the semiconductor film 31 on the gate insulating film 32. A gate electrode 33a is provided. Note that the gate electrode 33a is provided so as to be branched from the scanning line 33, and a region of the semiconductor film 31 facing the gate electrode 33a functions as a channel portion 31a. In the present embodiment, two gate electrodes 33a are provided in parallel to the semiconductor film 31, thereby forming a dual-gate transistor.

  An interlayer insulating film 12 is provided on the substrate 10A so as to cover the gate insulating film 32 and the gate electrode 33a, and a signal line 34 is provided on the insulating film 12. The insulating film 12 is provided with a contact hole 12a that communicates with the source portion 31b of the semiconductor film 31 and a contact hole 12b that communicates with the drain portion 31c. The signal line 34 includes the contact hole 12a and the gate insulating film. The source part 31 b is conductively connected through a contact hole 32 a provided in the base 32. Further, an interlayer insulating film 13 is provided on the substrate 10 A so as to cover the interlayer insulating film 12 and the signal line 34, and a pixel electrode 14 is provided on the insulating film 13. The insulating film 13 is provided with a contact hole 13 a that communicates with the contact hole 12 b of the insulating film 12. The pixel electrode 14 includes the contact holes 13 a and 12 b and the contact hole 32 b provided in the gate insulating film 32. Are electrically connected to the drain part 31c. The substrate configured as described above is further provided with an alignment film 15 made of polyimide or the like so as to cover the pixel electrode 14 and the interlayer insulating film 13.

  On the other hand, the counter substrate 20 is provided with a light-transmitting counter electrode 24 made of ITO or the like on a substrate body 20A made of a light-transmitting substrate such as glass or plastic. An alignment film 25 is provided.

[Method of manufacturing liquid crystal device]
Next, a method for manufacturing the liquid crystal display device 100 of the first embodiment will be described.
In the present embodiment, as shown in FIG. 5A, first, a semiconductor film 31 made of polycrystalline silicon is formed on the surface of a substrate 10A made of glass, plastic, or the like. The polycrystalline silicon film 31 can be formed as follows. First, a liquid repellent film (not shown) such as a fluororesin film is formed on the substrate 10A. Then, the element formation region of the liquid repellent film (that is, the position where the semiconductor film 31 is to be formed) is irradiated with ultraviolet rays, and the liquid repellent film in the element formation region is decomposed and patterned to form a liquid repellent bank. Thereafter, liquid silicon hydride is applied to the element formation region and dried. Next, the dried silicon hydride film is baked and thermally decomposed into an amorphous silicon film. Further, after irradiating the entire substrate with ultraviolet rays to decompose and remove the liquid repellent bank, the amorphous silicon film is irradiated with an excimer laser such as XeCl and annealed to polycrystallize the amorphous silicon film to form the polycrystalline silicon film 31. To. Thereafter, channel doping is performed on the semiconductor film 31 as necessary for Vth control and the like. That is, appropriate impurities (for example, phosphorus ions when forming an n-type conductive layer) are implanted and diffused over the entire surface.

  Next, as shown in FIG. 5B, columnar mask pillars (mask materials) 71a and 71b are formed in regions (positions where openings are to be formed) where contact holes (openings) 12a and 12b are to be formed. . The mask pillars 71a and 71b are formed by applying a liquid organic material such as a resist and solidifying it by using a quantitative discharge device such as a printer head of an ink jet printer. At this time, the film thickness (height) of the mask pillars 71 a and 71 b is equal to or greater than the film thickness of the interlayer insulating film 32. Thereby, it is possible to prevent the mask pillars 71a and 71b from being buried in the interlayer insulating film 32. Also, in this step, in order to prevent the dropped liquid material from spreading greatly around the position where the opening is to be formed, before the dropping, around the position where the openings 12a and 12b are formed on the substrate in advance. It is desirable to perform a liquid repellent treatment. This liquid repellent treatment can be performed by forming a liquid repellent film such as a fluororesin around the opening.

  Next, as shown in FIG. 5C, a gate insulating film 32 made of silicon oxide or the like is formed around the mask pillars 71a and 71b, that is, on the entire surface of the substrate excluding the mask pillars 71a and 71b. The gate insulating film 32 can also be formed by applying a liquid insulating material such as SOG to the entire surface of the substrate and baking it. As a method for applying the liquid insulating material, a known method such as a spin coating method, a dip coating method, a roll coating method, a curtain coating method, a spray method, or a droplet discharge method (ink jet method) can be used. In particular, in the spin coating method, since the liquid material is stretched by centrifugal force, an interlayer insulating film with high film thickness uniformity is formed. Therefore, in this embodiment, this gate insulating film is formed by the spin coat method. In addition to the above SOG, polysilazane, polyimide, Low-K material, or the like can be used as the liquid insulating material.

  At this time, in order to prevent the liquid insulating material from adhering to the upper portions of the mask pillars 71a and 71b, it is desirable to perform a liquid repellent treatment on the mask pillars 71a and 71b in advance before applying the liquid insulating material. In the liquid repellent treatment of the mask pillars 71a and 71b, a gas containing fluorine atoms such as carbon tetrafluoride is decomposed by atmospheric pressure plasma to generate active fluorine single atoms and ions, and the mask pillars are applied to the active fluorine. Can be done by exposing. When the mask pillars 71a and 71b are formed of a liquid repellent photoresist containing fluorine atoms, such a liquid repellent treatment is not necessary.

Next, as shown in FIG. 5D, the mask pillars 71a and 71b are removed using a stripping solution or the like. As a result, openings 32a and 32b are formed in the gate insulating film 32 at positions to be the source portions 31b and 31c of the semiconductor film 31, respectively.
Next, as shown in FIG. 6A, a gate electrode 33 a is formed at a position on the gate insulating film 32 facing the semiconductor film 31. In this step, first, a liquid repellent film is formed so as to cover the gate insulating film 32. Then, the substrate is irradiated with ultraviolet rays through a mask to decompose and remove the liquid repellent film disposed at the positions where the scanning lines 33 and gate electrodes 33a and 33a are to be formed. Thereby, a groove for wiring is formed in the liquid repellent film. Then, a liquid wiring material mainly composed of an organometallic compound is supplied into the groove, and this is heat-treated to form the scanning line 33 and the gate electrode 33a. Thereafter, the entire substrate is irradiated with ultraviolet rays to decompose and remove the remaining liquid repellent film.

Next, using the gate electrode 33a as a mask, appropriate impurities (for example, boron ions when a p-type conductive layer is formed) are implanted into the source part 31b and the drain part 31c of the semiconductor film 31. As a result, a channel portion 31a is formed in the region of the semiconductor film 31 shielded by the gate electrode 33a, and a source portion 31b and a drain portion 31c are formed at positions facing each other across the channel portion 31a.
Next, as shown in FIG. 6C, a resist 72, which is a photosensitive resin, is formed on the entire substrate so as to cover the gate electrode 33a, the gate insulating film 32, and the semiconductor film 31 by using a method such as spin coating. Form. At this time, the film thickness of the resist 72 disposed on the gate insulating film 32 is equal to or larger than the film thickness of the interlayer insulating film 12. Thereby, it is possible to prevent mask pillars 72a and 72b described later from being buried in the interlayer insulating film 12.

  Next, as shown in FIG. 6D, the resist 72 is exposed and developed to leave the resist only at the positions where the openings 32a and 32b are formed. As a result, a columnar mask pillar 72a that covers the inside of the opening 32a and protrudes on the gate insulating film 32 is formed at the position where the opening 32a is formed, and the position where the opening 32b is formed. A columnar mask pillar 72b is formed so as to cover the inside of the opening 32b and project on the gate insulating film 32.

Next, as shown in FIG. 7A, an interlayer insulating film 12 made of silicon oxide or the like is formed around the mask pillars 72a and 72b, that is, on the entire surface of the substrate excluding the mask pillars 72a and 72b. Similar to the gate insulating film 32, the interlayer insulating film 12 can be formed by applying a liquid insulating material to the entire surface of the substrate using a method such as a spin coating method and heat-treating it. At this time, in order to prevent the liquid insulating material from adhering to the upper portions of the mask pillars 72a and 72b, it is desirable to perform a liquid repellent treatment on the mask pillars 72a and 72b in advance before applying the liquid insulating material. When the mask pillars 72a and 72b are formed of a liquid repellent photoresist containing fluorine atoms, such a liquid repellent treatment is not necessary.
Next, as shown in FIG. 7B, the mask pillars 72a and 72b are removed using a stripping solution or the like. Thereby, in the interlayer insulating film 12, an opening 12a communicating with the opening 32a is formed, and an opening 12b communicating with the opening 32b is formed at the forming position of the opening 32b.

  Next, as shown in FIG. 7C, a signal line 34 that is electrically connected to the source portion 31b of the semiconductor film 31 is formed on the interlayer insulating film 12 through the openings 32a and 12a. In this step, first, a liquid contact forming material containing an organometallic compound as a main component is supplied into the openings 32a and 12a by using a quantitative discharge device, and the liquid contact forming material is fired and solidified to thereby open the openings. A connection plug 34a is formed in the portions 32a and 12a. At this time, in order to reliably fill the liquid material into the openings 32a and 12a, it is desirable to perform a lyophilic process in the opening before applying the liquid material. This lyophilic treatment can be performed, for example, by irradiating ultraviolet rays into the opening. Next, a liquid repellent film is formed so as to cover the interlayer insulating film 15, and a groove for a signal line is formed in the liquid repellent film by mask exposure. Then, a liquid wiring material mainly composed of an organometallic compound is supplied into the groove, and this is heat-treated to form the signal line 34. Thereafter, the entire substrate is irradiated with ultraviolet rays to decompose and remove the remaining liquid repellent film.

  Note that the connection plug 34 a may be formed simultaneously with the signal line 34. In this case, a liquid repellent film is formed at the stage of FIG. 7B, and the liquid repellent film disposed at the positions where the openings 32a and 12a and the signal line 34 are to be formed is decomposed and removed by mask exposure. Then, the connection plug 34 a can be formed simultaneously with the signal line 34 by supplying the liquid wiring material into the groove of the liquid repellent film thus formed and into the openings 32 a and 12 a.

Next, as shown in FIG. 8A, a resist 73, which is a photosensitive resin, is formed on the entire substrate so as to cover the signal line 34 and the interlayer insulating film 12 by using a method such as spin coating. At this time, the film thickness of the resist 73 disposed on the interlayer insulating film 12 is the same as the film thickness of the interlayer insulating film 13 or more. Thereby, it is possible to prevent a mask pillar 73a described later from being buried in the interlayer insulating film 13.
Next, as shown in FIG. 8B, the resist 73 is exposed and developed to leave the resist only at the positions where the openings 32b and 12b are formed. As a result, a columnar mask pillar (mask material) 73a is formed on the substrate so as to cover the inside of the openings 32b and 12b and protrude above the interlayer insulating film 12.

Next, as shown in FIG. 8C, an interlayer insulating film 13 made of silicon oxide or the like is formed around the mask pillar 73a, that is, on the entire surface of the substrate excluding the mask pillar 73a. Similar to the gate insulating film 32 and the interlayer insulating film 12, the interlayer insulating film 13 can be formed by applying a liquid insulating material using a method such as a spin coating method and heat-treating it. At this time, in order to prevent the liquid insulating material from adhering to the upper portion of the mask pillar 73a, it is desirable to perform a liquid repellent treatment on the mask pillar 73a in advance before applying the liquid insulating material. When the mask pillar 73a is formed of a liquid repellent photoresist containing fluorine atoms, such a liquid repellent treatment is not necessary.
Next, as shown in FIG. 9A, the mask pillar 73a is removed using a stripping solution or the like. Thereby, in the interlayer insulating film 13, an opening 13a communicating with these is formed at the position where the openings 32b and 12b are formed.

  Next, as shown in FIG. 9B, the pixel electrode 14 that is electrically connected to the drain portion 31c of the semiconductor film 31 is formed on the interlayer insulating film 13 through the openings 32b, 12b, and 13a. In this step, first, a liquid repellent film is formed so as to cover the interlayer insulating film 13, and a groove for the liquid repellent film pixel electrode is formed by mask exposure. Then, using a constant discharge device, for example, a liquid wiring material in which fine powder of ITO constituting a transparent conductive film is dispersed in an organic solvent is supplied into the groove, and this is heat-treated to form the pixel electrode 14. . Thereafter, the entire substrate is irradiated with ultraviolet rays to decompose and remove the remaining liquid repellent film. In this step, the conductive plug 14a disposed in the openings 32b, 12b, and 13a is formed at the same time as the pixel electrode 14, but the plug 14a and the pixel electrode 14 are made of different conductive materials. It can also be formed in a separate process.

Next, a polyimide solution is applied to the entire surface of the substrate so as to cover the pixel electrode 14 and the interlayer insulating film 13, and this is baked to form the alignment film 15.
Thus, the TFT array substrate 10 is manufactured.

On the other hand, for the counter substrate 20, first, a substrate body 20A made of glass or the like is prepared, and a light shielding film between pixels is formed by forming and patterning a light shielding material. Next, a transparent conductive material such as ITO is deposited on the entire surface of the substrate by sputtering or the like, and the counter electrode 24 is formed on almost the entire display area of the substrate body. Next, a polyimide solution is applied to the entire surface of the substrate so as to cover the counter electrode 24, and this is baked to form the alignment film 25.
Thus, the counter substrate 20 is manufactured.

  Next, the TFT array substrate 10 and the counter substrate 20 manufactured in this way are bonded together via a sealing material 52, and liquid crystal is injected into the space between the substrates 10 and 20 by a vacuum injection method. Form. Thereby, the liquid crystal display device of this embodiment is completed.

As described above, in the present embodiment, the mask pillar formed before the formation of the insulating film is peeled off after the formation of the insulating film, and the holes generated thereby are used as contact holes. For this reason, unlike the conventional method of opening the insulating film after the insulating film is formed, the substrate is not damaged. In particular, in this method, even if the interval between the layers to be connected becomes wide, it can be dealt with by simply changing the height (film thickness) of the mask material. There is no inconvenience such as increased damage.
In addition, in this method, since an opening with a large aspect ratio can be formed, it is not necessary to form a relay electrode as in the prior art. For this reason, it becomes possible to form a bright display device having a high aperture ratio.

  In this embodiment, all the openings are formed by forming / removing the mask pillars. However, it is not always necessary to prohibit etching in the process of forming all the openings. In other words, when the distance between the layers to be connected is small, for example, when there is only one insulating film disposed between the layers, even if the conventional method using etching is used, the substrate is caused by this. Damage and device characteristic degradation may be tolerated. Therefore, when a plurality of interlayer insulating films are disposed between the semiconductor layer and the pixel electrode, one or more interlayer insulating films close to the semiconductor layer are opened by a method such as etching, and the others Even if the interlayer insulating film is opened by forming / removing the above-described mask pillar, the object of improving the connection reliability of the wiring, which is the main object of the present invention, is sufficiently achieved. In this way, by providing room for introducing another method in the process of forming the opening, the degree of freedom of the process can be increased.

  Specifically, the openings 32a and 32b shown in FIG. 5D may be formed by conventional dry etching. In this case, the gate insulating film 32 corresponds to the first insulating film of the present invention, and the other insulating films 12 and 13 correspond to the second insulating film of the present invention.

[Electronics]
Next, specific examples of an electronic device including the liquid crystal device of the present invention will be described.
FIG. 10 is a perspective view showing an example of a portable information processing apparatus such as a word processor or a personal computer. 10, reference numeral 1200 denotes an information processing apparatus, reference numeral 1202 denotes an input unit such as a keyboard, reference numeral 1204 denotes an information processing apparatus body, and reference numeral 1206 denotes a display unit using the above-described liquid crystal device.
Since the electronic device shown in FIG. 10 includes the display unit using the liquid crystal device of the above-described embodiment, high-quality display can be performed by reliable switching.

In addition, this invention is not limited to the above-mentioned embodiment, It can implement in various deformation | transformation in the range which does not deviate from the meaning of this invention.
For example, the wiring structure of the electro-optical device described in the above embodiment is merely an example, and a structure in which two or four or more wiring layers are provided on the semiconductor layer 31 may be employed. Even in this case, the above-described method of forming / removing the mask can be used as a method for forming a contact hole for connecting a wiring layer or between a semiconductor layer and a wiring layer. In such a multilayer wiring structure, the effect of the present invention increases as the distance between the wiring layers to be connected increases, for example, as the number of wiring layers arranged between the connected wiring layers increases.

  Moreover, in the said embodiment, although the mask pillar was formed by the droplet discharge method or the spin coat method, it can select freely which method is taken. For example, the mask pillars 72a and 72b and the mask pillar 73a can be formed by a droplet discharge method. However, since it is difficult to form a columnar structure having a high aspect ratio by the droplet discharge method, it is preferable to select a coating method to be used depending on the depth of the contact hole to be formed. Specifically, when the contact hole to be formed is shallow (for example, when the number of interlayer insulating films penetrating the opening is one layer), a droplet discharge method is used and the contact hole is deep (for example, In the case where there are a plurality of layers of interlayer insulating films penetrating the opening), a photosensitive resin is formed on the entire surface of the substrate using a method such as spin coating, and this is patterned by exposure and development, A mask pillar may be formed. In the case of using the droplet discharge method, the liquid organic material to be discharged is not necessarily limited to the photosensitive resin, and may be, for example, a polyimide solution.

  In the above embodiment, the liquid crystal display device has been described as an example of the electro-optical device. However, the present invention can be applied to various devices such as an organic EL display device and an electrophoretic display device. it can.

1 is a plan view showing an overall structure of an electro-optical device according to an embodiment of the invention. Sectional drawing which follows the HH 'line of FIG. FIG. 2 is an equivalent circuit diagram of the electro-optical device in FIG. 1. The expanded sectional view which expanded the principal part of FIG. FIG. 5 is a process diagram for explaining a method for manufacturing an electro-optical device according to the invention. Process drawing following FIG. Process drawing following FIG. Process drawing following FIG. Process drawing following FIG. FIG. 11 illustrates an example of an electronic device of the invention.

Explanation of symbols

10A ... substrate, 12, 13, 32 ... insulating film, 12a, 12b, 13a, 32a, 32b ... opening, 14 ... pixel electrode (conductive layer), 30 ... TFT (semiconductor device) 31 ... Polycrystalline silicon film (semiconductor layer) 33 ... Scanning line (conductive layer) 33a ... Gate electrode (conductive layer) 34 ... Signal line (conductive layer) 71a, 71b, 72a , 72b, 73a... Mask pillar (mask material), 100... Liquid crystal display device (electro-optical device), 1200.

Claims (16)

A method of manufacturing a semiconductor device having a semiconductor layer and a conductive layer stacked via an insulating film,
Forming a semiconductor layer on the substrate;
Forming an insulating film having an opening at a predetermined position on the semiconductor layer;
Forming a conductive layer electrically connected to the semiconductor layer through the opening on the insulating film,
The step of forming the insulating film includes
Forming a mask material at the predetermined position on the semiconductor layer;
Forming an insulating film on the entire surface of the substrate excluding the mask material;
And a step of forming an opening in the insulating film by removing the mask material. A plurality of insulating films are disposed between the semiconductor layer and the conductive layer,
In the insulating film forming step, the mask material forming step, the insulating film forming step, and the mask material removing step are repeatedly performed to form an opening that penetrates the plurality of insulating films in the thickness direction. The method of manufacturing a semiconductor device according to claim 1, wherein: A method of manufacturing a semiconductor device having a semiconductor layer and a conductive layer stacked via an insulating film,
Forming a semiconductor layer on the substrate;
Forming an insulating film having an opening at a predetermined position on the semiconductor layer;
Forming a conductive layer that conducts through the opening on the insulating film,
The step of forming the insulating film includes
Forming a first insulating film having an opening at the predetermined position on the semiconductor layer;
Forming a mask material covering the inside of the opening and projecting on the first insulating film at the predetermined position on the substrate;
Forming a second insulating film on the entire surface of the substrate excluding the mask material;
And removing the mask material to form an opening that penetrates the second insulating film in the thickness direction and communicates with the opening of the first insulating film. Device manufacturing method. A plurality of insulating films are disposed between the semiconductor layer and the conductive layer,
In the insulating film forming step, after the first insulating film forming step, a mask material forming step, a second insulating film forming step, and a mask material removing step are performed in the opening of the first insulating film. 4. The method of manufacturing a semiconductor device according to claim 3, wherein an opening for communicating a plurality of insulating films disposed between the semiconductor layer and the conductive layer is formed by repeating.   The step of forming the first insulating film includes a step of forming an insulating film on the semiconductor layer and a step of removing the insulating film located in the formation region of the opening by using a photolithography technique. The method of manufacturing a semiconductor device according to claim 3, wherein:   2. The mask material forming step includes forming a photosensitive resin on the entire surface of the substrate, and exposing and developing the photosensitive resin to form a pattern at a position where the opening is to be formed. The manufacturing method of the semiconductor device in any one of -5.   6. The method according to claim 1, wherein in the step of forming the mask material, the mask material is formed by selectively discharging a liquid material to a position where the opening is to be formed and solidifying the liquid material. A method for manufacturing a semiconductor device according to any one of the above items. A method of manufacturing an electro-optical device having a semiconductor layer and a pixel electrode stacked via an insulating film,
Forming a semiconductor layer on the substrate;
Forming an insulating film having an opening at a predetermined position on the semiconductor layer;
Forming a pixel electrode that conducts through the opening on the insulating film,
The step of forming the insulating film includes
Forming a mask material at the predetermined position of the semiconductor layer;
Forming an insulating film on the entire surface of the substrate excluding the mask material;
And a step of forming an opening in the insulating film by removing the mask material. A plurality of insulating films are disposed between the semiconductor layer and the pixel electrode,
In the insulating film forming step, the mask material forming step, the insulating film forming step, and the mask material removing step are repeated to form an opening that penetrates the plurality of insulating films in the thickness direction. The method of manufacturing an electro-optical device according to claim 8. A method of manufacturing an electro-optical device having a semiconductor layer and a pixel electrode stacked via an insulating film,
Forming a semiconductor layer on the substrate;
Forming an insulating film having an opening at a predetermined position on the semiconductor layer;
Forming a pixel electrode that conducts through the opening on the insulating film,
The step of forming the insulating film includes
Forming a first insulating film having an opening at the predetermined position on the semiconductor layer;
Forming a mask material covering the inside of the opening and projecting on the first insulating film at the predetermined position on the substrate;
Forming a second insulating film on the entire surface of the substrate excluding the mask material;
And removing the mask material to form an opening that penetrates the second insulating film in the thickness direction and communicates with the opening of the first insulating film. Manufacturing method of optical device. A plurality of insulating films are disposed between the semiconductor layer and the pixel electrode,
In the insulating film forming step, after the first insulating film forming step, the mask material forming step, the second insulating film forming step, and the mask material removing step are repeated, whereby the semiconductor layer and the conductive layer are electrically conductive. 11. The method of manufacturing an electro-optical device according to claim 10, wherein an opening that communicates with a plurality of insulating films disposed between the layers is formed.   The step of forming the first insulating film includes a step of forming an insulating film on the semiconductor layer and a step of removing the insulating film located in the formation region of the opening by using a photolithography technique. The method of manufacturing an electro-optical device according to claim 10 or 11, wherein:   9. The mask material forming step includes forming a photosensitive resin on the entire surface of the substrate, and patterning the mask material at a position where the opening is to be formed by exposing and developing the photosensitive resin. The method for producing an electro-optical device according to any one of items 12 to 12.   The mask material is formed by selectively discharging a liquid material to a formation scheduled position of the opening and solidifying the liquid material in the step of forming the mask material. A method for manufacturing the electro-optical device according to any one of the above items.   An electronic apparatus comprising a semiconductor device manufactured using the method according to claim 1. An electronic apparatus comprising the electro-optical device manufactured using the method according to claim 8.

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