JP2000299470A - Semiconductor device and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form each circuit of an optoelectronic device with a TFT of an adequate structure depending on the function thereof, by forming a crystalline semiconductor film with a channel forming region of TFT included in a driver circuit, and also forming an amorphous semiconductor film with a channel forming area of TFT included in a pixel region. SOLUTION: A silicon oxide film 202 and an amorphous silicon film 203a are formed on a substrate 201. Thereafter, only a driver circuit is selectively crystallized with irradiation of laser to form an area 204a consisting of the crystallized silicon film. The formed crystalline silicon film 204a is patterned to form a semiconductor layer 204b of a TFT of the driver circuit and an amorphous silicon film 203a is patterned to form a semiconductor layer 203b of a TFT of the pixel region. As a result, each circuit of the elector-optical device represented with AM-LCD and EL display device can be formed with a TFT of the adequate structure depending on the function thereof, a an elector- optical device having higher reliability can also be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device having a circuit composed of thin film transistors (hereinafter, referred to as TFTs). For example, the present invention relates to an electro-optical device represented by a liquid crystal display panel and a configuration of an electronic device having such an electro-optical device as a component.

[0002] In this specification, a semiconductor device generally refers to a device that can function by utilizing semiconductor characteristics, and an electro-optical device, a semiconductor circuit, and an electronic device are all semiconductor devices.

[0003]

2. Description of the Related Art In recent years, a technique of forming a thin film transistor (TFT) using a semiconductor thin film (having a thickness of several to several hundred nm) formed on a substrate having an insulating surface has attracted attention. Thin film transistors are widely applied to electronic devices such as ICs and electro-optical devices, and are particularly rapidly developed as switching elements for image display devices.

For example, in a liquid crystal display device, a pixel portion for individually controlling pixels arranged in a matrix, a driver circuit for controlling the pixel portion, and a logic circuit (a processor circuit or a memory circuit) for processing an external data signal are provided. Attempts have been made to apply TFTs to all kinds of electric circuits.

A configuration (system-on-panel) in which these circuits (pixel unit, driver circuit, etc.) are integrated on one substrate is known. In the pixel portion, the pixel plays a role of holding information sent from the driver circuit. If the off-state current of the TFT connected to the pixel is not sufficiently small, the information cannot be held, and No indication can be obtained.

On the other hand, in a driver circuit, a TFT is required to have a high mobility, and the higher the mobility, the simpler the circuit structure can be, and the faster the display device can be operated.

As described above, the required characteristics are different between the TFT arranged in the driver circuit and the TFT arranged in the pixel portion. In other words, a TFT arranged in a pixel portion does not need to have a high mobility, but needs to have a small off-current and a uniform value in the pixel portion. Conversely, the mobility of TFTs of driver circuits arranged in the periphery is prioritized over off-current, and high mobility is required.

However, using a conventional manufacturing method, a TFT which gives priority to mobility and a TFT which has a small off-current are formed on the same substrate.
It has been difficult to manufacture FT with high productivity without impairing reliability.

[0009]

As described above, in order to realize a system-on-panel having a built-in logic circuit, a completely new structure not required in the past is required.

The present invention meets such a demand, and each circuit of an electro-optical device represented by an AM-LCD is formed by a TFT having an appropriate structure according to a function, and has high reliability. It is an object to provide an electro-optical device.

[0011]

According to the invention disclosed in this specification, in a semiconductor device having a driver circuit and a pixel portion formed on the same substrate, at least one TFT included in the driver circuit is provided. The channel formation region is made of a crystalline semiconductor film and includes a T
The FT channel formation region is a semiconductor device including an amorphous semiconductor film.

In the above structure, the channel forming region of at least one TFT included in the driver circuit is formed through an irradiation step using a laser or a similar strong light.

Further, in the above structure, at least one TFT included in the driver circuit and a channel formation region of the TFT included in the pixel portion are formed of a semiconductor film formed by a sputtering method.

Further, in the above structure, the gate insulating film of at least one TFT included in the driver circuit and the TFT included in the pixel portion is formed of an insulating film formed by a sputtering method.

Further, in the above structure, the crystalline semiconductor film is made of polysilicon, and the amorphous semiconductor film is made of amorphous silicon.

In each of the above structures, the semiconductor device is an active matrix display device, for example, an EL display device or a liquid crystal display device.

Further, the invention for realizing the above structure is a method for manufacturing a semiconductor device having a driver circuit and a pixel portion on the same substrate, wherein an amorphous semiconductor film is formed on an insulating surface. A first step, a second step of selectively irradiating the amorphous semiconductor film with a laser or a similar intense light to convert a part of the amorphous semiconductor film into a crystalline semiconductor film; A third step of patterning the crystalline semiconductor film to form a semiconductor layer of a driver circuit, patterning the amorphous semiconductor film to form a semiconductor layer in a pixel portion, and forming an insulating film on the semiconductor layer A fourth step;
A fifth step of forming a gate electrode on the insulating film.

Further, in the above structure, the fourth step is performed by a sputtering method.

Another aspect of the invention is a method for manufacturing a semiconductor device having a driver circuit and a pixel portion on the same substrate, wherein a first method for forming an amorphous semiconductor film on an insulating surface is provided.
And forming a second insulating film on the amorphous semiconductor film.
And a third step of selectively irradiating the amorphous semiconductor film with a laser beam or similar intense light through the insulating film to form a part of the amorphous semiconductor film into a crystalline semiconductor film. A fourth step of forming a semiconductor layer of a driver circuit by patterning the crystalline semiconductor film and forming a semiconductor layer of a pixel portion by patterning the amorphous semiconductor film; and forming a gate on the insulating film. A fifth step of forming an electrode;
And a method for manufacturing a semiconductor device.

Further, in the above structure relating to the manufacturing method, the second step is performed by a sputtering method.

In each of the above structures relating to the manufacturing method, the first step is performed by a sputtering method.

Another aspect of the invention is a method of manufacturing a semiconductor device having a driver circuit and a pixel portion on the same substrate, wherein a first step of forming a gate electrode on an insulating surface; A second step of forming an insulating film thereon;
A third step of forming an amorphous semiconductor film on the insulating film;
A fourth step of selectively irradiating the amorphous semiconductor film with a laser or similar intense light to turn a part of the amorphous semiconductor film into a crystalline semiconductor film; Patterning to form a semiconductor layer of a driver circuit, and patterning the amorphous semiconductor film to form a semiconductor layer of a pixel portion.

In each of the above structures relating to the manufacturing method, after the fifth step, a sixth step of selectively adding an element belonging to Group 15 or Group 13 to a region to be a source region or a drain region; And a seventh step of activating the elements belonging to Group 13 and Group 15 added to the semiconductor layer.

In each of the above structures relating to the manufacturing method, the semiconductor device is a liquid crystal display device.

In the above structure relating to the manufacturing method, an eighth step of forming an interlayer insulating film above the active layer after the seventh step of performing an activation process, and forming a pixel electrode on the interlayer insulating film A ninth step of forming an EL layer on the pixel electrode, and an eleventh step of forming a cathode or an anode on the EL layer.

In each of the above structures relating to the manufacturing method, the semiconductor device is an EL display device.

[0027]

Embodiments of the present invention will be described below. In the present invention, an amorphous semiconductor film or a crystalline semiconductor film is used as an active layer of a TFT of each circuit of an electro-optical device represented by an AM-LCD or an EL display device formed on the same substrate according to a function. It is characterized by using. For example, in an electro-optical device represented by an AM-LCD or an EL display device, an amorphous semiconductor film (amorphous silicon film or the like) is used as an active layer of a TFT disposed in a pixel portion, and a driver circuit, a logic circuit, or the like is used. As described above, the T
As an FT active layer, a crystalline semiconductor film (polysilicon film,
(A polycrystalline silicon film or the like).

In order to realize the above configuration, it is necessary to selectively crystallize an amorphous semiconductor film on the same substrate to form a crystalline semiconductor film, and the present invention has a feature in a method of forming the same. is there.

An example of the forming method of the present invention will be described with reference to FIG. FIG. 1 is a simplified diagram showing an example in which only an amorphous semiconductor film of a driver circuit 103 formed on a substrate is irradiated with a pulsed laser such as an excimer laser.

In FIG. 1, reference numeral 101 denotes a substrate having heat resistance, such as a glass substrate, a quartz substrate, a silicon substrate, a ceramics substrate, or a metal substrate (typically, a stainless steel substrate).
May be used. Whichever substrate is used, a base film (preferably, an insulating film containing silicon as a main component) may be provided as necessary. Although not shown, the substrate 10
On 1 is provided an amorphous semiconductor film formed by a sputtering method. Therefore, at this stage, a clear boundary is not actually visible, but for convenience, the pixel portion 102 and the driver circuit 103 which are formed later are shown.

The laser light emitted from the excimer laser light source 105 is applied to an optical system (beam homogenizer 10).
6, a mirror 107, etc.) to adjust the beam shape, the energy density, and the like, thereby forming a laser spot 108. The XY stage 1 on which the substrate 101 is fixed
04 in the X or Y direction,
A laser spot 108 is applied only to the amorphous semiconductor film of the driver circuit 103 in a laser spot scan direction 109.
Irradiation. However, taking into account the thickness of the amorphous semiconductor film, etc., the laser light conditions (irradiation intensity, pulse width, repetition frequency, irradiation time, substrate temperature, stage moving speed, overlap ratio, etc.) Is appropriately determined. Here, when laser light leaks and irradiates the pixel portion 102, the characteristics of the TFT vary, so it is important to arrange the optical system so that the laser light does not leak. In addition, it is necessary to appropriately set the distance X between the driver circuit and the pixel portion.

When the laser irradiation method shown in FIG. 1 is used, only the driver circuit 103 can be irradiated with laser light, and the amorphous silicon film can be selectively crystallized.

As the laser light, a continuous wave laser such as an argon laser, a continuous wave excimer laser, or the like can be used in addition to a pulsed laser such as an excimer laser.

Further, a step of irradiating the above laser beam after forming an insulating film on the amorphous semiconductor film may be performed.

FIG. 6 shows an example in which a continuous wave laser such as an argon laser is irradiated. 6, reference numeral 601 denotes a substrate; 606, a beam expander;
07 is a galvanometer, and 604 is a single axis operation stage. Although not shown, an amorphous semiconductor film is provided over the substrate 601 by a sputtering method.

The laser light emitted from the argon laser light source 605 is applied to an optical system (beam expander 60).
6, galvanometer 607, f-theta lens 608
The beam spot 609 is formed by adjusting the beam shape, the energy density, and the like. Then, by oscillating the galvanometer, the laser spot 6
09 is oscillated in a direction parallel to the laser spot scanning direction 610, and at the same time, the single-axis operation stage 604 to which the substrate 601 is fixed is step-moved in one direction (the operation direction 611 of the single-axis operation stage). By doing so, only the amorphous semiconductor film of the driver circuit 603 is crystallized. As in the case of the laser irradiation method shown in FIG.

When the laser irradiation method shown in FIG. 6 is used, only the driver circuit can be irradiated with laser light in the same manner as the laser irradiation method shown in FIG. 1, and the amorphous silicon film can be selectively crystallized. Can be done.

Further, in addition to the structures shown in FIGS. 1 and 6, a resist mask using a normal photolithography process may be formed on the substrate so that the laser beam does not leak to the pixel portion. May be used.

Although FIGS. 1 and 6 show an example in which a spot laser is formed, the present invention is not particularly limited, and a configuration in which a linear laser beam is selectively irradiated using a mask may be used. Alternatively, a process may be used in which a large area spot laser typified by sopra is processed into a driver circuit size, and an amorphous semiconductor region of the driver circuit is simultaneously crystallized.

FIG. 4C is a cross-sectional view of an AM-LCD in which a driver circuit and a pixel portion are integrally formed on the same substrate by using the laser light irradiation method of the present invention. Here, a CMOS circuit is shown as a basic circuit constituting a driver circuit, and a double-gate TFT is shown as a TFT in a pixel portion. Of course, not only the double gate structure but also a triple gate structure or a single gate structure may be used.

Reference numeral 202 denotes a silicon oxide film provided as a base film, on which an active layer of a TFT of a driver circuit, an active layer of a TFT of a pixel portion, and a semiconductor layer serving as a lower electrode of a storage capacitor are formed. Note that in this specification, an “electrode” is a part of a “wiring” and indicates a portion where an electrical connection with another wiring is made or a portion which intersects with a semiconductor layer. Therefore, for convenience of explanation, “wiring” and “electrode” are properly used, but it is assumed that the term “wiring” always includes “electrode”.

In FIG. 4C, T of the driver circuit
The active layer of the FT is an N-channel type TFT (hereinafter, NTFT).
Source region 221, drain region 220, L
It is formed of a DD (lightly doped drain) region 228 and a channel formation region 209, and a source region 215, a drain region 216, and a channel formation region 217 of a P-channel TFT (hereinafter, PTFT).

The TFT (here, NTFT) of the pixel portion
Is used. The active layer is formed by the source region 222, the drain region 224, the LDD region 229, and the channel forming region 212. Further, a semiconductor layer extended from the drain region 224 is used as the lower electrode 226 of the storage capacitor.

Although the lower electrode 226 is directly connected to the drain region 224 of the TFT in the pixel portion in FIG. 1, the lower electrode 226 is electrically connected to the drain region 224 by indirect connection. Such a structure may be used.

The lower electrode 226 is doped with an element belonging to Group 15 of the semiconductor layer. That is, even if a voltage is not applied to the upper wiring 206f of the storage capacitor, it can be used as it is as an electrode.
-Effective for reducing the power consumption of the LCD.

The TFT channel forming region 212 of the pixel portion is an amorphous semiconductor film, and the TFT channel forming regions 209 and 217 of the driver circuit are formed.
Is a feature of the present invention in that it is a crystalline semiconductor film having crystallinity.

The channel forming region 20 of each TFT
Reference numerals 9, 212, and 217 denote semiconductor films formed by a sputtering method, and one of the aspects of the present invention is that the film has a low hydrogen concentration. A semiconductor film formed by a sputtering method has a hydrogen concentration lower by one digit or more than that of a semiconductor film formed by a plasma CVD method, and can be continuously laser-crystallized after film formation without dehydrogenation treatment. On the other hand, the process using the plasma CVD method has a high risk of explosion, and is disadvantageous from the viewpoint of working environment safety. In the present invention, in order to prioritize safety and productivity, a thin film such as an amorphous semiconductor film (amorphous silicon film), an insulating film, a conductive layer, or the like is formed by a sputtering method.
More preferably, each film is continuously formed as much as possible to prevent contamination from the atmosphere.

Further, here, the gate insulating film 205 of each TFT is the same insulating film having the same thickness, but is not particularly limited. For example, a configuration may be adopted in which at least two or more TFTs having different gate insulating films exist on the same substrate depending on circuit characteristics. Note that it is preferable to form the semiconductor film and the gate insulating film continuously by a sputtering method because a favorable interface can be obtained.

Next, a gate wiring 206d of the TFT of the driver circuit and a gate wiring 206e of the TFT of the pixel portion are formed on the gate insulating film 205. At the same time, the gate insulating film 205 is formed on the lower electrode 226 of the storage capacitor.
The upper electrode 206f of the storage capacitor is formed via.

As the wiring material of the present invention, typically,
Conductive silicon film (for example, phosphorus-doped silicon film,
A boron-doped silicon film or the like, a metal film (for example, a tungsten film, a tantalum film, a molybdenum film, a titanium film, an aluminum film, a copper film, or the like) may be used. A tantalum film, a tungsten nitride film, a titanium nitride film, or the like).
Further, these may be freely combined and laminated.

When the metal film is used, it is preferable that the metal film has a laminated structure with a silicon film in order to prevent oxidation of the metal film. In terms of preventing oxidation, a structure in which a metal film is covered with a silicon nitride film is effective.

Next, reference numeral 230 denotes a first interlayer insulating film, which is formed of an insulating film containing silicon (single layer or multilayer). As the insulating film containing silicon, a silicon oxide film, a silicon nitride film, a silicon oxynitride film (having a higher nitrogen content than oxygen), and a silicon nitride oxide film (having a higher oxygen content than nitrogen) ) Can be used.

A contact hole is provided in the first interlayer insulating film 230, and the source wirings 231 and 233 and the drain wiring 232 of the TFT of the driver circuit, and the source wiring 234 and the drain wiring 235 of the TFT of the pixel portion are provided.
Is formed. On top of that, a passivation film 236,
After a second interlayer insulating film 237 is formed and a contact hole is provided, a pixel electrode 238 is formed.

Although a black mask (light-shielding film) is not formed in FIG. 4C, it is not particularly limited, and may be formed as needed. For example, a structure in which a light-shielding film is provided on the opposite substrate may be employed, or a structure in which a light-shielding film using a material similar to that of the gate wiring is provided below or above each TFT.

As the second interlayer insulating film 237, a resin film having a small relative dielectric constant is preferable. As the resin film, a polyimide film, an acrylic film, a polyamide film, a BCB (benzocyclobutene) film, or the like can be used.

The pixel electrode 238 is a transmission type A
To manufacture an M-LCD, a transparent conductive film typified by an ITO film may be used, and to manufacture a reflective AM-LCD, a metal film having a high reflectivity typified by an aluminum film may be used.

In FIG. 4, the pixel electrode 238 is connected through the drain electrode 235 to the drain region 22 of the TFT in the pixel portion.
4, the pixel electrode 238 and the drain region 224 may be directly connected.

The AM-LCD having the above structure is
Since each circuit is formed by a TFT having an appropriate structure according to the function, it is characterized by high driving ability, reliability, and productivity.

The present invention having the above configuration will be described in more detail with reference to the following embodiments.

[0060]

[Embodiment 1] In this embodiment, a manufacturing process for realizing the structure of FIG. 4C described in "Embodiment of the Invention" will be described. 2 to 4 are used for the description.

First, a glass substrate 201 is prepared as a substrate, and a 200-nm-thick silicon oxide film (also referred to as a base film) 202 and a 55-nm-thick amorphous silicon film 203a are continuously formed thereon without opening to the atmosphere. The film was formed by a sputtering method.
(FIG. 2A) By doing so, it is possible to prevent impurities such as boron contained in the atmosphere from adsorbing to the lower surface of the amorphous silicon film 203a.

In this embodiment, an amorphous silicon (amorphous silicon) film is used as the amorphous semiconductor film, but another semiconductor film may be used. An amorphous silicon germanium film may be used. As a means for forming the base film and the semiconductor film, a PCVD method, an LPCVD method, a sputtering method, or the like can be used. Among them, the sputtering method is preferable because it is excellent in safety and productivity. The sputtering apparatus used in this embodiment includes a chamber, an exhaust system that evacuates the chamber, a gas introduction system that introduces a sputtering gas into the chamber, an electrode system including a target and an RF electrode, and an electrode. A sputtering power supply connected to the system. In this embodiment, argon (Ar) was used as a sputtering gas and a silicon target was used as a target.

In this embodiment, the channel forming region of the TFT in the pixel portion is formed of an amorphous silicon film (the field effect mobility μ _FE of the NTFT made of an amorphous silicon film is smaller than 1.0 cm ² / Vs). Therefore, it is necessary to appropriately set the channel length and the thickness of the amorphous silicon film.

Next, the amorphous silicon film 204a is crystallized. As a means for crystallization, a known technique such as laser crystallization or thermal crystallization using a catalytic element is used. In this embodiment, laser crystallization was performed by using the laser irradiation method shown in FIG. The laser beam emitted from the excimer laser light source 105 was adjusted in beam shape and energy density by an optical system (beam homogenizer 106, mirror 107, etc.) to form a laser spot 108. Then, the XY stage 104 to which the substrate 101 was fixed was moved in the X direction or the Y direction, so that only the amorphous semiconductor film of the driver circuit 103 was irradiated with the laser spot 108 in the laser spot scanning direction 109. Thus, laser irradiation was performed only on the driver circuit to selectively crystallize, thereby forming a region 204a made of a crystalline silicon (polysilicon) film. (FIG. 2 (B))

In the present embodiment, the T
The channel formation region of the FT is a crystalline silicon film (the field effect mobility μ _FE of the NTFT formed of the crystalline silicon film is 1.0 cm ²
/ Vs or more), it is necessary to appropriately set the optimum channel length and the thickness of the amorphous silicon film that can be sufficiently laser-crystallized. In consideration of the above, the channel length may be 3 to 10 μm, and the thickness of the amorphous silicon film is 10 to 200 nm, preferably 30 to 7 nm.
It may be 0 nm.

Then, the formed crystalline silicon (polysilicon) film is patterned to form a TFT of a driver circuit.
Was formed, and an amorphous silicon (amorphous silicon) film was patterned to form a semiconductor layer 203b of a TFT in a pixel portion. (Fig. 2 (C))

Before and after forming the TFTs of the driver circuit and the semiconductor layers 203b and 204b of the TFTs in the pixel portion, an impurity element (phosphorous or boron) for controlling the threshold voltage of the TFT is applied to the crystalline silicon film. ) May be added. This step may be performed only on the NTFT or PTFT, or may be performed on both.

Next, a gate insulating film 205 is formed by a sputtering method or a plasma CVD method, and a first conductive film 206a and a second conductive film 207a are stacked by a sputtering method. (FIG. 2 (D))

The gate insulating film 205 is to function as a gate insulating film of a TFT, and has a thickness of 50 to 200 nm. In this embodiment, the sputtering method using a silicon oxide
A silicon oxide film having a thickness of nm was formed. A stacked structure in which a silicon nitride film is provided over a silicon oxide film as well as a silicon oxide film can be used, or a silicon oxynitride film in which nitrogen is added to a silicon oxide film can be used.

In this embodiment, an example is shown in which an amorphous silicon film is laser-crystallized and then patterned to form a gate insulating film. However, the process order is not particularly limited.
After an amorphous silicon film and a gate insulating film are continuously formed by a sputtering method, laser crystallization and patterning may be performed. When the film is continuously formed by the sputtering method, good interface characteristics can be obtained.

The first conductive film 206a is made of Ta, T
A conductive material mainly containing an element selected from i, Mo, and W is used. The thickness of the first conductive film 206a is 5 to 50 n
m, preferably 10 to 25 nm. On the other hand, the second conductive film 207a uses a conductive material mainly containing Al, Cu, and Si. The second conductive film 207a is 1
The thickness may be from 00 to 1000 nm, preferably from 200 to 400 nm. The second conductive film 207a is provided for reducing the wiring resistance of a gate wiring or a gate bus line.

Next, an unnecessary portion of the second conductive film 207a is removed by patterning, an electrode 207b to be a part of a gate bus line is formed in a wiring portion, and resist masks 208a to 208d are formed. Resist mask 2
08a covers the PTFT, and the resist mask 208b is formed so as to cover the channel formation region of the NTFT of the driver circuit. The resist mask 208c covers the electrode 207b, and the resist mask 208d covers the channel formation region of the pixel portion. Thereafter, an impurity element for imparting n-type is added using the resist masks 208a to 208d as masks, and impurity regions 210 and 211 are added.
Was formed. (FIG. 3 (A))

In this embodiment, the impurity element imparting n-type
Phosphine (PH) _ThreeIo using)
The doping method was used. In this step, the gate insulating film 205
Through the first conductive film 206a and the semiconductor layer 20 thereunder.
In order to add phosphorus to 3b and 204b, the accelerating voltage is 8
0 keV was set higher. Semiconductor layer 203b,
The concentration of phosphorus added to 204b was 1 × 10¹⁶~ 1 ×
10¹⁹atoms / cm^ThreeIt is preferable that the range is
1 × 10¹⁸atoms / cm^ThreeAnd Then, phosphorus is added to the semiconductor layer.
Regions 210 and 211 were formed. here
Part of the formed phosphorus-added region is an LDD region.
Function as It is also covered with a mask and phosphorus added
Region (region 209 made of a crystalline silicon film,
Part of the region 212) made of a crystalline silicon film has a channel shape.
Functions as a growth area.

In the step of adding phosphorus, an ion implantation method that performs mass separation may be used, or a plasma doping method that does not perform mass separation may be used.
Further, the condition of the acceleration voltage and the dose amount may be set by the practitioner to the optimal values.

Next, after removing the resist masks 208a to 208d, an activation process is performed if necessary. Then, a third conductive film 213a was formed by a sputtering method.
(FIG. 3B) The third conductive film 213a is made of Ta, Ti,
A conductive material mainly containing an element selected from Mo and W is used. The thickness of the third conductive film 213a is 100 to 1
000 nm, preferably 200 to 500 nm.

Next, the resist masks 214a to 214d are
Formed and patterned to form a PTFT gate electrode
Formation of 206b and 213b, and wiring 206c and 213
After the formation of c, the masks 214a to 214d are used as they are.
To add a p-type impurity element,
A source region and a drain region. (Fig. 3 (C))
Here, boron is used as an impurity element and diborane (B_Two
H₆) And added by an ion doping method. Here
Assuming that the speed voltage is 80 keV, 2 × 10²⁰atoms / cm ^ThreeNo
Boron was added each time.

Next, after removing the resist masks 214a to 214d and newly forming resist masks 218a to 218e, etching is performed using the resist masks 218a to 218e as masks, and gate wirings 206d and 213d of NTFT are formed.
The gate wirings 206e and 213e of the TFT in the pixel portion and the upper wirings 206f and 213f of the storage capacitor are formed. (FIG. 3
(D))

Next, the resist masks 218a to 218e are removed and a new resist mask 219 is formed.
Impurity regions 220 to 225 are formed by adding an impurity element imparting n-type to the source region and the drain region of the FT. (FIG. 4A) Here, phosphine (PH ₃ )
The ion doping method using was performed. Impurity region 220-
The concentration of phosphorus added to H.225 is higher than that in the step of adding the impurity element imparting n-type,
It is preferably set to × 10 ¹⁹ to 1 × 10 ²¹ atoms / cm ³ ,
Here, it is set to 1 × 10 ²⁰ atoms / cm ³ .

Then, after removing the resist mask 219, a protective film 227 made of a silicon nitride film having a thickness of 50 nm is formed.
Is formed to obtain the state shown in FIG.

Next, an activation process for activating the added impurity element imparting n-type or p-type is performed.
This step includes a thermal annealing method using an electric heating furnace, a laser annealing method using an excimer laser described above, and a rapid thermal annealing method (R
TA method). 300-
The heat treatment was performed at 700 ° C., preferably 350 to 550 ° C., and in this example, at 450 ° C. for 2 hours in a nitrogen atmosphere.

Next, after forming the first interlayer insulating film 230, contact holes are formed, and source and drain electrodes 231 to 235 are formed by a known technique.

After that, a passivation film 236 is formed. As the passivation film 236, a silicon nitride film, a silicon oxynitride film, a silicon nitride oxide film, or a stacked film of these insulating films and a silicon oxide film can be used.
In this embodiment, a silicon nitride film having a thickness of 300 nm is used as a passivation film.

In this embodiment, as a pretreatment for forming a silicon nitride film, a plasma treatment using an ammonia gas is performed, and the passivation film 236 is formed as it is.
Hydrogen activated (excited) by plasma by this pretreatment is confined by the passivation film 236, so that hydrogen termination of the active layer (semiconductor layer) of the TFT can be promoted.

Further, when nitrous oxide gas is added in addition to the gas containing hydrogen, the surface of the object to be treated is washed by the generated moisture, and it is possible to effectively prevent the contamination by boron and the like contained in the air. it can.

After forming the passivation film 236,
After forming an acrylic film having a thickness of 1 μm as the second interlayer insulating film 237, patterning was performed to form a contact hole, and a pixel electrode 238 made of an ITO film was formed. Thus, an AM-LCD having a structure as shown in FIG. 4C is completed.

With the above steps, the NTFT of the driver circuit
The channel formation region 209 and the impurity regions 220 and 22
1. LDD region 228 was formed. Impurity region 220
Is a source region, and the impurity region 221 is a drain region. In the NTFT of the pixel portion, the channel formation region 212, the impurity regions 222 to 225, and the LDD region 2
29 were formed. Here, the LDD regions 228, 229
A region (GOLD region) overlapping the gate electrode and a region (LDD region) not overlapping the gate electrode were formed.

On the other hand, in the p-channel TFT, a channel formation region 217 and impurity regions 215 and 216 were formed. Then, the impurity region 215 became a source region and the impurity region 216 became a drain region.

As described above, the present invention relates to a TFT of a pixel portion having a channel forming region 212 made of an amorphous silicon film on the same substrate and a driver circuit having channel forming regions 209 and 217 made of a crystalline silicon film. The feature is that a TFT is formed. With such a configuration, the TFT of the pixel portion with high uniformity and the TFT of the driver circuit with high mobility
The FT can be formed on the same substrate.

FIG. 5A shows an example of a circuit configuration of an active matrix type liquid crystal display device. The active matrix type liquid crystal display device of this embodiment includes a source signal line side driver circuit 301 and a gate signal line side driver circuit (A).
307, gate signal line side driver circuit (B) 311,
A precharge circuit 312 and a pixel portion 306 are provided.

The source signal line side driver circuit 301 is
Shift register circuit 302, level shifter circuit 303,
A buffer circuit 304 and a sampling circuit 305 are provided.

The gate signal line side driver circuit (A) 307 includes a shift register circuit 308, a level shifter circuit 309, and a buffer circuit 310. The gate signal line side driver circuit (B) 311 has the same configuration.

In the present invention, a circuit other than the pixel portion is used as a driver circuit to crystallize the semiconductor layer in that region, but is not particularly limited. That is, among the driver circuits, those circuits that require higher reliability than high mobility do not have to be crystallized. For example, among the driver circuits, the buffer circuit and the like may have a channel formation region formed of an amorphous semiconductor layer, similarly to the NTFT in the pixel portion.

Further, according to the present invention, it is easy to make the lengths of the LDD regions different on the same substrate in consideration of the driving voltage of the NTFT, and the optimum shape for the TFT constituting each circuit is obtained. Can be made in the same process.

FIG. 5B is a top view of the pixel portion, and shows a cross-sectional structure taken along line AA ′ of the TFT portion and a line BB ′ of the wiring portion.
Since the cross-sectional structure corresponds to that of FIG. 4C, some of them are denoted by the same reference numerals. In FIG. 5B, reference numeral 401 denotes a semiconductor layer, 402 denotes a gate electrode, and 403a denotes a capacitor line. In this embodiment, the gate electrode and the gate wiring 403
b is formed of a first conductive layer and a third conductive layer, and the gate bus line is formed of the first conductive layer, the second conductive layer, and the third conductive layer.
And a cladding structure formed from the conductive layer.

FIG. 10A is a top view of a CMOS circuit which is a part of a driver circuit, and FIG.
(C). In this embodiment, the active layers of the NTFT and PTFT are in direct contact with each other and share the drain electrode. However, the present invention is not particularly limited to this structure, and the structure (active layer is completely separated) as shown in FIG. ).

[Embodiment 2] In this embodiment, an example of selectively crystallizing an amorphous semiconductor film using a laser different from that in Embodiment 1 will be described below with reference to FIG. This example is the same as Example 1 except for the laser crystallization step.
The description will be focused on only the differences.

First, a silicon oxide film (underlying film) and an amorphous silicon film are continuously formed on a substrate according to the manufacturing process of the first embodiment. In this embodiment, a quartz substrate was used as the substrate. Also,
The thickness of the amorphous silicon film is preferably 100 nm or more due to the relationship of the absorption coefficient of the argon laser.

Next, at the time of laser crystallization, selective crystallization is performed using the irradiation method shown in FIG. The laser light emitted from the argon laser light source 605 is supplied to an optical system (beam expander 606, galvanometer 60).
7, f-theta lens 608, etc.) to adjust the beam shape and energy density, etc.
9 was formed. Then, the laser spot 609 is vibrated in a direction parallel to the laser spot scanning direction 610 by vibrating the galvanometer, and at the same time,
The single-axis operation stage 604 to which the substrate 601 is fixed is step-moved in one direction (the operation direction 611 of the single-axis operation stage) (the interval between steps is approximately the spot diameter), and laser driver irradiation is performed only on the driver circuit. Then, a region made of a crystalline silicon (polysilicon) film was formed.

The subsequent steps will be described with reference to FIG.
Can be obtained.

[Embodiment 3] In the manufacturing steps shown in Embodiments 1 and 2, the laser irradiation method shown in FIG. 1 or FIG. 2 is used to selectively irradiate only the driver circuit. It is also possible to selectively irradiate laser light using a mask.

In this case, a conventional laser irradiation device can be used as it is. Therefore, it can be said that this is an effective technique because it can be easily performed without changing the apparatus.

The structure of this embodiment can be freely combined with any one of the first and second embodiments.

[Embodiment 4] In this embodiment, an example in which an AM-LCD is manufactured by a process different from that of Embodiment 1 will be described with reference to FIGS. In the first embodiment, an example of a top gate type TFT is shown.
An example of T is shown.

First, a gate electrode 702 having a laminated structure (not shown for simplicity) is formed on a glass substrate 701. In this embodiment, a tantalum nitride film and a tantalum film are stacked by sputtering, and gate wirings (including gate electrodes) 702a to 702c and capacitor wirings 702d are formed by known patterning.

Next, a gate insulating film and an amorphous semiconductor film were sequentially formed without opening to the atmosphere. In this embodiment, a stacked layer of a silicon nitride film and a silicon oxide film is formed by a sputtering method to form a gate insulating film having a stacked structure. (FIG. 7A)
An amorphous silicon film was formed by a sputtering method without opening to the atmosphere. Although the amorphous semiconductor film formed by a sputtering method has a low hydrogen concentration, heat treatment for further reducing the hydrogen concentration may be performed.

In this embodiment, the channel forming region of the TFT in the pixel portion is formed of an amorphous silicon film (the field effect mobility μ _FE of the NTFT made of an amorphous silicon film is smaller than 1.0 cm ² / Vs). Therefore, it is necessary to appropriately set the channel length and the thickness of the amorphous silicon film.

Next, laser crystallization is selectively performed.
A crystalline silicon film 706 was formed. In this embodiment, only the driver circuit was irradiated with laser light using the laser irradiation method shown in FIG. (FIG. 7 (B))

In this embodiment, the driver circuit T
The channel formation region of the FT is a crystalline silicon film (the field effect mobility μ _FE of the NTFT formed of the crystalline silicon film is 1.0 cm ²
/ Vs or more), it is necessary to appropriately set the optimum channel length and the thickness of the amorphous silicon film that can be sufficiently laser-crystallized. In consideration of the above, the channel length may be 3 to 10 μm, and the thickness of the amorphous silicon film is 10 to 200 nm, preferably 30 to 7 nm.
It may be 0 nm.

Next, a channel protective film 707 for protecting the channel formation region is formed. This channel protective film 70
7 may be formed using known patterning. In this embodiment, patterning is performed using a photomask. In this state, the surface of the crystalline silicon film or the amorphous silicon film other than the region in contact with the channel protective film 707 is exposed. (FIG. 7C) In the case of performing patterning using exposure from the back surface, a photomask is not required, so that the number of steps can be reduced.

Next, a resist mask 708 covering a part of the PTFT and the NTFT was formed by patterning using a photomask. Next, an impurity element imparting n-type (phosphorus in this embodiment) was added to form an impurity region 709. (FIG. 8A)

Next, after removing the resist mask 708, the entire surface was covered with a thin insulating film. This thin insulating film is formed for adding an impurity element at a low concentration and is not particularly required. (FIG. 8 (B))

Next, the impurity element was added at a lower concentration than in the previous step of adding the impurity element. (FIG. 8C) In this step, the crystalline silicon film covered with the channel protective film 707 becomes the channel formation region 713, and the amorphous silicon film covered with the channel protective film 707 becomes the channel formation region 71.
It becomes 4. In addition, LDD regions 711 and 712 of NTFT were formed by this process.

Next, a resist mask 715 covering the entire surface of the N-channel TFT was formed, and an impurity element imparting p-type was added. (FIG. 8D) In this step, the crystalline silicon film covered with the channel protective film 707 becomes a channel formation region 716 of the PTFT, and a source region and a drain region 717 of the PTFT are formed in this step.

Next, after removing the resist mask 715, the semiconductor layer was patterned into a desired shape. (FIG. 9
(A))

Next, after forming the first interlayer insulating film 722, a contact hole is formed, and a source electrode and a drain electrode 723 to 727 are formed by a known technique.

Thereafter, a passivation film 728 is formed. As the passivation film 728, a silicon nitride film, a silicon oxynitride film, a silicon nitride oxide film, or a stacked film of these insulating films and a silicon oxide film can be used.
In this embodiment, a silicon nitride film having a thickness of 300 nm is used as a passivation film.

In this embodiment, as a pretreatment for forming a silicon nitride film, a plasma treatment using ammonia gas is performed, and a passivation film 728 is formed as it is.
Hydrogen activated (excited) by plasma by this pretreatment is confined by the passivation film 728, so that hydrogen termination of the active layer (semiconductor layer) of the TFT can be promoted.

After forming the passivation film 728,
After forming an acrylic film having a thickness of 1 μm as the second interlayer insulating film 729, patterning was performed to form a contact hole, and a pixel electrode 730 made of an ITO film was formed. Thus, an AM-LCD having a structure as shown in FIG. 9C is completed.

Further, the structure of this embodiment can be freely combined with any one of Embodiments 2 and 3.

[Embodiment 5] In this embodiment, a case where another means is used for forming a crystalline silicon film in Embodiment 1 will be described.

More specifically, the crystallization of an amorphous silicon film is disclosed in Japanese Patent Application Laid-Open No. Hei 7-130652 (US Patent No. 08/32).
9, 644) is used. The technology described in the publication discloses a catalyst element that promotes crystallization (cobalt, palladium, germanium, platinum,
This is a technique in which iron, copper, typically nickel) is selectively held on the surface of an amorphous silicon film, and crystallization is performed using the portion as a seed for nucleus growth.

According to this technique, a specific directionality can be given to crystal growth, so that a crystalline silicon film having extremely high crystallinity can be formed.

The structure of this embodiment can be freely combined with any of the structures of the first to fourth embodiments.

[Embodiment 6] In this embodiment, a case where another means is used for forming a crystalline silicon film in Embodiment 1 will be described.

In this embodiment, nickel is selected as a catalyst element, and a layer containing nickel is formed on the amorphous silicon film.
Crystallization was performed by performing a process of selectively irradiating laser light.

Next, a resist mask is formed on the silicon film, and a step of adding an element belonging to Group 15 (phosphorus in this embodiment) is performed. The concentration of phosphorus to be added is 5 × 10 ¹⁸ to 1 × 1
0 ²⁰ atoms / cm ³ (preferably 1 × 10 ^{19 to} 5 × 10 ¹⁹ ato
ms / cm ³ ). However, the concentration of phosphorus to be added is
The concentration is not limited to this range because it varies depending on the temperature and time of the subsequent gettering step and the area of the phosphorus-doped region. Thus, a region to which phosphorus was added (hereinafter, referred to as a phosphorus-doped region) was formed.

The resist mask is arranged so as to expose a part (or all) of a region which will be a source region or a drain region of a TFT of a driver circuit later. Similarly, the resist mask is arranged so that part (or all) of the source region or the drain region of the TFT in the pixel portion is exposed later. At this time, since a resist mask is not arranged in a region serving as a lower electrode of the storage capacitor,
Phosphorus is entirely added to form a phosphorus-doped region.

Next, the resist mask is removed and 500
A heat treatment at 〜650 ° C. is applied for 2 to 16 hours to getter the catalytic element (nickel in this embodiment) used for crystallization of the silicon film. To achieve the gettering action, a temperature of about ± 50 ° C from the maximum temperature of the heat history is required,
Since the heat treatment for crystallization is performed at 550 to 600 ° C., the gettering effect can be sufficiently obtained by the heat treatment at 500 to 650 ° C.

Then, the crystalline silicon (polysilicon) film in which the catalytic element was reduced was patterned to form a crystalline semiconductor layer of the TFT of the driver circuit and an amorphous semiconductor layer of the TFT of the pixel portion. Subsequent steps may follow the first embodiment.

The structure of this embodiment can be freely combined with any of the structures of the first to fifth embodiments.

[Embodiment 7] In this embodiment, an example of forming a source region and a drain region by adding an element belonging to Group 13 or 15 in a different order from that of Embodiment 1 will be described. In the present invention, the doping order can be appropriately changed. In the doping sequence of the first embodiment, first, low-concentration phosphorus is added, second, boron is added, and third, high-concentration phosphorus is added. In this embodiment, FIG. B)
First, an example in which a high concentration of phosphorus is added after obtaining the state shown in FIG.

First, in accordance with the steps of Embodiment 1, FIG.
Get the state of.

Next, a resist mask for forming NTFT wiring is formed. This resist mask is PT
Cover FT. Etching is performed using this resist mask as a mask to form a gate wiring of NTFT, a gate wiring of TFT in a pixel portion, and an upper wiring of a storage capacitor.

Next, after removing the resist mask and forming a new resist mask, the source region of NTFT,
An impurity region is formed by adding an impurity element imparting n-type to the drain region. At this time, the concentration of added phosphorus is 5 × 10 ¹⁹ to 1 × 10 ²¹ atoms / cm ³ .

Next, a resist mask covering a region other than the PTFT is formed. Then, a boron addition step is performed.
At this time, the concentration of boron to be added is 1 × 10 ^{20 to} 3 × 1.
0 ²¹ atoms / cm ³ . Thus, the source region, the drain region, and the channel formation region of the PTFT are defined.

The following steps may follow the manufacturing steps of the first embodiment. The configuration of this embodiment can be freely combined with any one of Embodiments 1 to 6.

[Embodiment 8] The present invention relates to a conventional MOSFE.
It is also possible to form an interlayer insulating film on T and use it when forming a TFT thereon. That is, it is also possible to realize a semiconductor device having a three-dimensional structure in which a reflective AM-LCD is formed on a semiconductor circuit.

The semiconductor circuit is SIMOX, Sm
art-Cut (registered trademark of SOITEC), ELTRAN
(A registered trademark of Canon Inc.) may be formed on an SOI substrate.

In implementing this embodiment, any of the configurations of Embodiments 1 to 7 may be combined.

[Embodiment 9] In this embodiment, a TFT is formed on a substrate by the manufacturing process shown in Embodiment 1,
A case where an LCD is manufactured will be described.

When the state shown in FIG. 4C is obtained, an alignment film is formed on the pixel electrode 238 to a thickness of 80 nm. next,
A color filter, a transparent electrode (counter electrode), and an alignment film are formed on a glass substrate as a counter substrate, and a rubbing process is performed on each alignment film. The substrate on which is formed is bonded to the counter substrate. Then, the liquid crystal is held in the meantime. Since a well-known means may be used for this cell assembling step, a detailed description is omitted.

A spacer for maintaining the cell gap may be provided as needed. Therefore, when the cell gap can be maintained without the spacer as in the case of an AM-LCD having a diagonal of 1 inch or less, it is not necessary to particularly provide the cell gap.

Next, the AM-L manufactured as described above was used.
FIG. 11 shows the appearance of the CD. As shown in FIG. 11, an active matrix substrate and a counter substrate face each other, and a liquid crystal is sandwiched between these substrates. The active matrix substrate includes a pixel portion 1001, a scanning line driver circuit 1002, and a signal line driver circuit 100 formed over a substrate 1000.
3

The scanning line driver circuit 1002 and the signal line driver circuit 1003 are connected to the pixel portion 1001 by a scanning line 1030 and a signal line 1040, respectively.
These driver circuits 1002 and 1003 are mainly constituted by CMOS circuits.

A scanning line is formed for each row of the pixel portion 1001, and a signal line 1040 is formed for each column. In the vicinity of the intersection of the scanning line 1030 and the signal line 1040, a TFT 1010 in a pixel portion is formed. TFT10 of pixel part
The ten gate electrodes are connected to the scanning lines 1030, and the sources are connected to the signal lines 1040. Further, a pixel electrode 1060 and a storage capacitor 1070 are connected to the drain.

In the counter substrate 1080, a transparent conductive film such as an ITO film is formed on the entire surface of the substrate. The transparent conductive film is the pixel portion 1
The liquid crystal material is driven by an electric field formed between the pixel electrode 1060 and the pixel electrode 1060. An alignment film, a black mask, and a color filter are formed on the counter substrate 1080 as necessary.

The substrate on the active matrix substrate side has F
IC chip 10 using the surface on which PC 1031 is mounted
32, 1033 are attached. These IC chips 1032 and 1033 are configured by forming circuits such as a video signal processing circuit, a timing pulse generating circuit, a gamma correction circuit, a memory circuit, and an arithmetic circuit on a silicon substrate.

Further, in this embodiment, a liquid crystal display device is described as an example, but the present invention is applied to an EL (electroluminescence) display device or an EC (electrochromics) display device as long as it is an active matrix type display device. It is also possible to apply the invention.

This embodiment can be freely combined with any one of Embodiments 1 to 8.

[Embodiment 10] In this embodiment, an example in which an active matrix EL display device is manufactured by using the present invention is shown in FIGS.

FIG. 12 is a simplified circuit diagram of an active matrix type EL display device. Reference numeral 11 denotes a pixel portion, around which an X-direction driver circuit 1 is provided.
2. A Y-direction driver circuit 13 is provided. Each pixel of the pixel section 11 includes a switching TFT 14, a capacitor 15, a current controlling TFT 16, and an organic EL element 1.
7 and the switching TFT 14 is connected to the X-direction signal line 18a.
(Or 18b), the Y-direction signal line 20a (or 20b,
20c) is connected. Power supply lines 19a and 19b are connected to the current control TFT 16.

In this embodiment, the X-direction driver circuit 12,
The semiconductor layer of the TFT used for the Y-direction driver circuit 13 is formed of polysilicon, and the TFT used for the pixel portion 11 is
The FT semiconductor layer is formed of amorphous silicon.

The structure of the TFT used in the X-direction driver circuit 12 and the Y-direction driver circuit 13 is GOL.
D structure, switching TFT 14 and current control TF
The TFT structure of T16 is an LDD structure.

FIG. 13 (A) shows an example of E using the present invention.
It is a top view of an L display device. In FIG. 13A, 4
010, a substrate; 4011, a pixel portion; 4012, a source side driver circuit; 4013, a gate side driver circuit;
At 017, it is connected to an external device.

At this time, the cover member 600 is formed so as to surround at least the pixel portion, preferably, the driving circuit and the pixel portion.
0, sealing material (also referred to as housing material) 7000,
A sealing material (a second sealing material) 7001 is provided.

FIG. 13B shows a cross-sectional structure of the EL display device of this embodiment.
A driving circuit TFT 4022 (here, a CMOS circuit combining an n-channel TFT and a p-channel TFT is illustrated) 4022 and a pixel portion TFT 40
23 (however, here, TF for controlling the current to the EL element)
Only T is shown. ) Is formed. Here, an example using a bottom gate type TFT by the manufacturing method shown in Embodiment 4 is shown, but there is no particular limitation.
A known structure (a top gate structure or a bottom gate structure) may be used.

Using the present invention, a TFT 4022 for a drive circuit having an active layer made of a crystalline semiconductor film and a TFT 402 for a pixel portion having an active layer made of an amorphous semiconductor film
3 is completed, a pixel electrode 4027 made of a transparent conductive film electrically connected to the drain of the pixel portion TFT 4023 is formed on an interlayer insulating film (flattening film) 4026 made of a resin material.
To form As the transparent conductive film, a compound of indium oxide and tin oxide (called ITO) or a compound of indium oxide and zinc oxide can be used. After the pixel electrode 4027 serving as an anode is formed, an insulating film 4028 is formed, and an opening is formed over the pixel electrode 4027.

Next, an EL layer 4029 is formed. The EL layer 4029 is formed of a known EL material (a hole injection layer, a hole transport layer,
A light-emitting layer, an electron transport layer, or an electron injection layer) may be freely combined to form a stacked structure or a single-layer structure. A known technique may be used to determine the structure. Also, E
The L material includes a low molecular material and a high molecular (polymer) material. When a low molecular material is used, an evaporation method is used, but when a high molecular material is used, a spin coating method,
A simple method such as a printing method or an inkjet method can be used.

In this embodiment, an EL layer is formed by an evaporation method using a shadow mask. By forming a light-emitting layer (a red light-emitting layer, a green light-emitting layer, and a blue light-emitting layer) capable of emitting light having different wavelengths for each pixel using a shadow mask, color display becomes possible. In addition, the color conversion layer (CC
M) and a color filter are combined, and a white light-emitting layer and a color filter are combined. Either method may be used. Needless to say, a monochromatic EL display device can be used.

After forming the EL layer 4029, the cathode 4030 is formed thereon. Cathode 4030 and EL layer 4029
It is desirable to remove as much as possible moisture and oxygen existing at the interface. Therefore, the EL layer 4029 and the cathode 40 in vacuum
It is necessary to devise a method of continuously forming the film 30 or forming the EL layer 4029 in an inert atmosphere and forming the cathode 4030 without opening to the atmosphere. In this embodiment, the above-described film formation is made possible by using a multi-chamber type (cluster tool type) film formation apparatus.

In this embodiment, the cathode 4030 is
A laminated structure of a LiF (lithium fluoride) film and an Al (aluminum) film is used. Specifically, a 1-nm-thick LiF (lithium fluoride) film is formed over the EL layer 4029 by a vapor deposition method, and a 300-nm-thick aluminum film is formed thereover. Of course, a MgAg electrode which is a known cathode material may be used. The cathode 4030 is connected to the wiring 4016 in a region indicated by 4031. A wiring 4016 is a power supply line for applying a predetermined voltage to the cathode 4030, and the FPC 401 via the conductive paste material 4032.
7 is connected.

In the region indicated by 4031, the cathode 40
In order to electrically connect the wiring 30 and the wiring 3016, it is necessary to form contact holes in the interlayer insulating film 4026 and the insulating film 4028. These are at the time of etching the interlayer insulating film 4026 (at the time of forming the contact hole for the pixel electrode).
Or when the insulating film 4028 is etched (when an opening is formed before the EL layer is formed). Also, the insulating film 40
When etching 28, etching may be performed all at once up to the interlayer insulating film 4026. In this case, the interlayer insulating film 40
If the same resin material is used for the insulating film 26 and the insulating film 4028, the shape of the contact hole can be made good.

The passivation film 6003 and the filler 600 cover the surface of the EL element thus formed.
4. The cover material 6000 is formed.

Further, a sealing material is provided inside the cover material 6000 and the substrate 4010 so as to surround the EL element portion, and a sealing material (second sealing material) 7001 is formed outside the sealing material 7000.

At this time, the filler 6004 also functions as an adhesive for bonding the cover material 6000.
As the filler 6004, PVC (polyvinyl chloride), epoxy resin, silicone resin, PVB (polyvinyl butyral), or EVA (ethylene vinyl acetate) can be used. It is preferable to provide a desiccant inside the filler 6004 because a moisture absorbing effect can be maintained.

[0166] A spacer may be contained in the filler 6004. At this time, the spacer may be a granular substance made of BaO or the like, and the spacer itself may have hygroscopicity.

When a spacer is provided, the passivation film 6003 can reduce the spacer pressure.
Further, a resin film or the like for relaxing the spacer pressure may be provided separately from the passivation film.

As the cover member 6000, a glass plate, an aluminum plate, a stainless steel plate, FRP (Five)
rglass-Reinforced Plastic
s) plate, PVF (polyvinyl fluoride) film,
Mylar film, polyester film or acrylic film can be used. The filling material 600
When PVB or EVA is used as 4, it is preferable to use a sheet having a structure in which aluminum foil of several tens of μm is sandwiched between PVF films or Mylar films.

However, depending on the direction of light emission (the direction of light emission) from the EL element, the cover material 6000 needs to have translucency.

The wiring 4016 is made of a sealing material 700.
0 and through the gap between the sealing material 7001 and the substrate 4010, and is electrically connected to the FPC 4017. Although the wiring 4016 has been described here, the other wiring 401
4, 4015 are similarly electrically connected to the FPC 4017 under the sealant 7000 and the sealant 7001.

In this embodiment, since the pixel electrode is used as an anode, it is preferable to use a PTFT as the current controlling TFT. Embodiment 4 may be referred to for the manufacturing process. In the case of this embodiment, light generated in the light emitting layer is emitted toward the substrate on which the TFT is formed. Further, it may be formed using the NTFT of the present invention. When an NTFT is used as the current controlling TFT, a pixel electrode (cathode of an EL element) made of a highly reflective conductive film is used as a TFT for a pixel portion.
An EL layer and an anode made of a light-transmitting conductive film may be sequentially formed by being connected to the drain of the FT 4023. In this case, light generated in the light emitting layer is radiated toward the substrate on which the TFT is not formed.

This embodiment can be freely combined with any of Embodiments 1 to 8.

[Embodiment 11] Various electro-optical devices (active matrix liquid crystal display device, active matrix EL display device, active matrix EC display device) may be used for a CMOS circuit and a pixel portion formed by implementing the present invention. Can be used. That is, the invention of the present application can be implemented in all electronic devices in which these electro-optical devices are incorporated as display units.

Examples of such electronic devices include a video camera, a digital camera, a projector (rear or front type), a head mounted display (goggle type display), a car navigation system, a personal computer, and a portable information terminal (mobile computer, mobile phone). Or an electronic book). Examples of these are shown in FIGS.

FIG. 14A shows a personal computer comprising a main body 2001, an image input section 2002, and a display section 20.
03, a keyboard 2004 and the like. The present invention can be applied to the image input unit 2002, the display unit 2003, and other signal driving circuits.

FIG. 14B shows a video camera, which includes a main body 2101, a display portion 2102, an audio input portion 2103, operation switches 2104, a battery 2105, and an image receiving portion 210.
6 and so on. The present invention can be applied to the display portion 2102 and other signal driver circuits.

FIG. 14C shows a mobile computer (mobile computer), which includes a main body 2201, a camera section 2202, an image receiving section 2203, operation switches 2204, a display section 2205, and the like. The present invention can be applied to the display portion 2205 and other signal driving circuits.

FIG. 14D shows a part (right side) of a head-mounted display, which includes a main body 2301, a signal cable 2302, a head fixing band 2303, and a display section 230.
4, including an optical system 2305, a display device 2306, and the like. The present invention can be used for the display device 2306.

FIG. 14E shows a player using a recording medium (hereinafter, referred to as a recording medium) on which a program is recorded, and includes a main body 2401, a display section 2402, and a speaker section 240.
3, a recording medium 2404, an operation switch 2405, and the like. This player uses a DVD (D
digital Versatile Disc), CD
And the like, it is possible to perform music appreciation, movie appreciation, games, and the Internet. The present invention can be applied to the display portion 2402 and other signal driver circuits.

FIG. 14F shows a digital camera, which includes a main body 2501, a display section 2502, an eyepiece section 2503, operation switches 2504, an image receiving section (not shown), and the like. The present invention can be applied to the display portion 2502 and other signal driver circuits.

FIG. 15A shows a mobile phone,
01, audio output unit 2902, audio input unit 2903, display unit 2904, operation switch 2905, antenna 2906
And so on. The present invention can be applied to the audio output unit 2902, the audio input unit 2903, the display unit 2904, and other signal driving circuits.

FIG. 15B shows a portable book (electronic book), which includes a main body 3001, display portions 3002 and 3003, a storage medium 3004, operation switches 3005, and an antenna 3006.
And so on. The present invention can be applied to the display units 3002 and 3003 and other signal circuits.

FIG. 15C shows a display, which includes a main body 3101, a support 3102, a display portion 3103, and the like.
The present invention can be applied to the display portion 3103. The display of the present invention is particularly advantageous when the screen is enlarged, and is advantageous for a display having a diagonal of 10 inches or more (particularly 30 inches or more).

As described above, the applicable range of the present invention is extremely wide, and the present invention can be applied to electronic devices in various fields. Further, the electronic apparatus according to the present embodiment can be realized by using any combination of the embodiments 1 to 10.

[0185]

According to the present invention, the AM-L
By forming each circuit of an electro-optical device represented by a CD or an EL display device with a TFT having an appropriate structure according to a function, an electro-optical device having high reliability can be realized.

[Brief description of the drawings]

FIG. 1 is a view showing a laser irradiation method of the present invention.

FIG. 2 is a diagram showing a manufacturing process of an AM-LCD.

FIG. 3 is a view showing a manufacturing process of an AM-LCD.

FIG. 4 is a diagram showing a manufacturing process of an AM-LCD.

FIG. 5 is a top view of a pixel portion and a diagram showing a circuit arrangement.

FIG. 6 is a view showing a laser irradiation method of the present invention.

FIG. 7 is a diagram showing a manufacturing process of an AM-LCD.

FIG. 8 is a diagram showing a manufacturing process of an AM-LCD.

FIG. 9 is a diagram showing a manufacturing process of an AM-LCD.

FIG. 10 is a top view of a CMOS circuit.

FIG. 11 is a diagram showing an appearance of an AM-LCD.

FIG. 12 is a circuit diagram of an active matrix EL display device.

FIG. 13 is an external view of an active matrix EL display device.

FIG. 14 illustrates an example of an electronic device.

FIG. 15 illustrates an example of an electronic device.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 21/203 G02F 1/136 500 21/336 H01L 29/78 627G

Claims (19)

[Claims] In a semiconductor device having a driver circuit and a pixel portion formed on the same substrate, a channel forming region of at least one TFT included in the driver circuit is made of a crystalline semiconductor film, A channel formation region of a TFT included in the semiconductor device is formed of an amorphous semiconductor film. 2. The semiconductor device according to claim 1, wherein a channel forming region of at least one TFT included in said driver circuit is formed through an irradiation step using a laser or a similar intense light. 3. The semiconductor device according to claim 1, wherein at least one TFT included in the driver circuit and a channel forming region of the TFT included in the pixel portion are formed of a semiconductor film formed by a sputtering method. Characteristic semiconductor device. 4. The gate insulating film according to claim 1, wherein at least one of the TFTs included in the driver circuit and a gate insulating film of the TFT included in the pixel portion are formed by a sputtering method. A semiconductor device characterized by the above-mentioned. 5. The semiconductor device according to claim 1, wherein said crystalline semiconductor film is made of polysilicon, and said amorphous semiconductor film is made of amorphous silicon. 6. A semiconductor device according to claim 1, wherein the semiconductor device is an EL display device. 7. A semiconductor device according to claim 1, wherein the semiconductor device is a liquid crystal display device. 8. A semiconductor device comprising the semiconductor device according to claim 1 as a display unit. 9. The semiconductor device according to claim 8, wherein the semiconductor device is a video camera, a digital camera, a projector, a goggle type display, a car navigation, a personal computer, or a portable information terminal. 10. A method for manufacturing a semiconductor device having a driver circuit and a pixel portion on the same substrate, comprising: a first step of forming an amorphous semiconductor film on an insulating surface; A second step of selectively irradiating a laser or a similar intense light thereto to turn a part of the amorphous semiconductor film into a crystalline semiconductor film, and patterning the crystalline semiconductor film to form a semiconductor of a driver circuit. Forming a layer, patterning the amorphous semiconductor film to form a semiconductor layer in a pixel portion, forming an insulating film on the semiconductor layer, forming a gate electrode on the insulating film. Forming a semiconductor device. 11. The method according to claim 10, wherein the fourth step is performed by a sputtering method. 12. A method for manufacturing a semiconductor device having a driver circuit and a pixel portion on the same substrate, comprising: a first step of forming an amorphous semiconductor film on an insulating surface; A second step of forming an insulating film on the amorphous semiconductor film through the insulating film, and selectively irradiating the amorphous semiconductor film with a laser or similar intense light to part of the amorphous semiconductor film. A third step of forming a crystalline semiconductor film; a fourth step of patterning the crystalline semiconductor film to form a semiconductor layer of a driver circuit; and patterning the amorphous semiconductor film to form a semiconductor layer of a pixel portion. And a fifth step of forming a gate electrode on the insulating film. 13. The method for manufacturing a semiconductor device according to claim 12, wherein said second step is performed by a sputtering method. 14. The method for manufacturing a semiconductor device according to claim 10, wherein the first step is performed by a sputtering method. 15. A method for manufacturing a semiconductor device having a driver circuit and a pixel portion on the same substrate, comprising: a first step of forming a gate electrode on an insulating surface; and forming an insulating film on the gate electrode. A second step, a third step of forming an amorphous semiconductor film on the insulating film, and selectively irradiating the amorphous semiconductor film with a laser or similar intense light to form the amorphous semiconductor film. A fourth step of forming a part of the semiconductor film as a crystalline semiconductor film; patterning the crystalline semiconductor film to form a semiconductor layer of a driver circuit; and patterning the amorphous semiconductor film to form a semiconductor layer of a pixel portion. Forming a semiconductor device. 16. The semiconductor device according to claim 10, wherein, after the fifth step, a region to be a source region or a drain region is reduced by 15%.
A sixth step of selectively adding an element belonging to Group 13 or Group 13 and a seventh step of performing a treatment for activating the element belonging to Group 13 and Group 15 added to the semiconductor layer. Of manufacturing a semiconductor device. 17. The method for manufacturing a semiconductor device according to claim 10, wherein the semiconductor device is a liquid crystal display device. 18. The method according to claim 16, wherein after the seventh step of performing the activation process, an eighth step of forming an interlayer insulating film above the active layer, and a step of forming a pixel electrode on the interlayer insulating film. A method for manufacturing a semiconductor device, comprising: nine steps; a tenth step of forming an EL layer on the pixel electrode; and an eleventh step of forming a cathode or an anode on the EL layer. 19. The method for manufacturing a semiconductor device according to claim 10, wherein the semiconductor device is an EL display device.