JP2004119989A - Method for producing active matrix display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a proper active matrix display device. <P>SOLUTION: Linear or rectangular laser light, irradiating an area where a source driver circuit is formed in an active matrix display device has a sufficient dimension to irradiate the entire area where the source driver circuit is formed, and a region, where the source driver circuit is formed is subjected to the irradiation with the substrate and the laser light being not moved. A linear or rectangular laser irradiating an area where a gate driver circuit and an active matrix circuit are formed has a sufficient dimension to irradiate the entire region, where the source driver circuit is formed, and the region where the gate driver circuit and the active matrix circuit are formed is subjected to irradiation, while the substrate and the laser light being moved. <P>COPYRIGHT: (C)2004,JPO

Description

(4) The present invention relates to laser light irradiation treatment (so-called laser annealing method) in a semiconductor device manufacturing process. In particular, the present invention is a semiconductor material partially or wholly composed of an amorphous component, or a substantially intrinsic polycrystalline semiconductor material, further damaged by ion irradiation, ion implantation, ion doping, etc. The present invention relates to a method for improving the crystallinity of a semiconductor material or recovering the crystallinity by irradiating a semiconductor material having significantly impaired crystallinity with laser light.

Recently, research has been actively conducted on lowering the temperature of semiconductor device processes. The major reason is that a semiconductor element needs to be formed on an insulating substrate such as glass. In addition, there is a demand for miniaturization of elements and multi-layering of elements.

In the semiconductor process, the amorphous component contained in the semiconductor material or the amorphous semiconductor material is crystallized, or the crystallinity of the semiconductor material, which was originally crystalline but has been reduced in crystallinity due to irradiation with ions. In some cases, it may be necessary to restore the crystallinity or to improve the crystallinity. Conventionally, thermal annealing has been used for such a purpose. When silicon is used as a semiconductor material, annealing is performed at a temperature of 600 ° C. to 1100 ° C. for 0.1 to 48 hours or longer to obtain amorphous crystallization, recovery of crystallinity, and crystallization. Have been improved.

熱 Generally, the higher the temperature, the shorter the processing time may be. However, at a temperature of about 600 ° C., a long time processing is required. Therefore, from the viewpoint of lowering the temperature of the process, it has been necessary to replace the step conventionally performed by thermal annealing with another means. Laser light irradiation technology is attracting attention as the ultimate low-temperature process. That is, the laser light can be applied only to a required portion with high energy equivalent to thermal annealing, and it is not necessary to expose the entire substrate to a high temperature. Regarding the irradiation of laser light, roughly two methods have been proposed.

(1) The first method uses a continuous wave laser such as an argon ion laser, and irradiates a semiconductor material with a spot beam. This is a method in which a semiconductor material is melted and then solidified slowly by a difference in energy distribution inside the beam and movement of the beam to crystallize the semiconductor material.

The second method is a method in which a semiconductor material is crystallized by irradiating a semiconductor material with a high-energy laser pulse using a pulsed laser such as an excimer laser to instantaneously melt and solidify the semiconductor material.

The problem with the first method is that the processing takes time. This is because the maximum energy of the continuous wave laser is limited, and the size of the beam spot is at most mm. On the other hand, in the second method, the maximum energy of the laser was very large, and therefore, mass productivity could be further improved by using a large spot of several cm ² or more.

However, in the case of irradiating a pulsed laser, even if energy uniformity within a one-shot pulse beam can be achieved by improving the optical system, it is difficult to improve variation in element characteristics due to overlapping pulses. Was. In particular, when the element is located just at the end of the laser beam, the characteristics of the element (especially the threshold voltage of the MOS transistor) vary considerably.

Regarding semiconductor devices, the variation in threshold voltage is considerably allowed in digital circuits, but the variation in threshold voltage of adjacent transistors is required to be 0.02 V or less in analog circuits. Was.

The present invention has been made for the purpose of solving this problem. In order to eliminate the variation due to the overlap of the laser beams, it is ideal to perform the laser beam irradiation with a large beam that can irradiate the whole circuit at once, but it is not practically possible. Therefore, in the present invention, a sufficient characteristic can be obtained as a whole by dividing the substrate into a relatively narrow region where the laser beams do not overlap and a relatively wide region where the laser beams overlap.

In the present invention, the circuit on the substrate is divided into a circuit region centered on an analog circuit and a circuit region having a thin analog element, and the size of the laser light beam is further reduced in the circuit region centered on the analog circuit. It is possible to irradiate the entire circuit area centered on the analog circuit with the laser light without substantially moving the laser light.

(4) In a circuit region centering on the analog circuit, the laser beam is irradiated substantially without moving the laser. That is, in the circuit region centering on the analog circuit, the laser beams are not substantially overlapped.

On the other hand, in a circuit area where analog elements are thin, laser light irradiation is performed by scanning with laser light. As a result, laser beams overlap in this region.

For example, in a liquid crystal display (monolithic liquid crystal display) in which an active matrix circuit and a peripheral circuit (driver circuit) for driving the active matrix circuit are formed on the same substrate, a circuit region centering on an analog circuit is defined as an active circuit. It is a driver circuit for driving the matrix, especially a source driver (column driver) circuit for outputting analog signals. On the other hand, a circuit region having a thin analog element is an active matrix circuit or a gate driver (scan driver) circuit.

In order to carry out the present invention, it is necessary to match the shape of the laser beam to such a circuit, or to match the shape of the circuit to the laser beam, but it is generally a linear or rectangular shape. Is desirable. Also, for example, since the column driver and the scan driver of the liquid crystal display are formed substantially orthogonally, in order to perform these processes, the direction of the laser beam may be changed or the direction of the substrate may be changed by about 1/4 turn. (More generally, (n / 2 + ／) (n is a natural number) rotations).

By performing the processing as described above, in the analog circuit area, no overlap can be made, and only the in-plane uniformity of the laser beam is controlled. As a result, an element with uniform characteristics can be formed by sufficiently improving the in-plane uniformity of the laser beam. On the other hand, in a circuit region where analog elements are thin, variations in characteristics due to the overlap of laser beams are inevitable, but in the first place, in such a circuit, a slight variation is allowed, so there is no substantial problem. .

As described above, according to the present invention, as a whole circuit formed on the substrate, the adverse effect due to the overlap of the laser beams can be removed, and the characteristics of the whole circuit can be improved.

に お い て In the present invention, the shape of the object to be irradiated with the laser may be a film shape having no pattern or a device having a substantially completed device shape. Hereinafter, the present invention will be described in more detail with reference to Examples.

(4) The characteristics of the semiconductor circuit as a whole can be improved by the laser beam irradiation technique of the present invention while maintaining mass productivity. The present invention can be used for all laser processing processes used for semiconductor device processes. In particular, when a TFT is taken as a semiconductor device, a polycrystalline silicon film is used to improve the uniformity of the threshold voltage of the TFT. The effect is great when used in the step of laser irradiation. In addition, in order to improve the field effect mobility of the TFT or the uniformity of the on-current, it is effective to use the present invention in the step of activating the source / drain impurity elements in addition to the above steps. Thus, the present invention is considered industrially beneficial.

FIG. 4 shows a conceptual diagram of the laser annealing apparatus used in this embodiment. The laser light is oscillated by an oscillator 42, amplified by an amplifier 43 via total reflection mirrors 45 and 46, and further introduced into an optical system 44 via total reflection mirrors 47 and 48. The laser beam up to that time has a rectangular shape of about 30 × 90 mm ² , and is processed into an elongated beam having a length of 100 to 300 mm and a width of 10 to 30 mm by the optical system 64. The energy of the laser beam passing through this optical system was 30 J / shot at maximum.

The optical path inside the optical system 44 is shown as in FIG. The laser light incident on the optical system 44 passes through a cylindrical concave lens A, a cylindrical convex lens B, a horizontal fly-eye lens C, and a vertical fly-eye lens D. By passing through these fly-eye lenses C and D, the laser light changes from the Gaussian distribution type to the rectangular distribution. Further, the light passes through the cylindrical convex lenses E and F, passes through the mirror G (mirror 59 in FIG. 5), is focused by the cylindrical lens H, and is irradiated on the sample.

In this embodiment, the distances X ₁ and X ₂ in FIG. 5 are fixed, and the distance X ₃ between the virtual focus I (which is caused by the difference in the curved surface of the fly-eye lens) and the mirror G, and the distance The magnification M and the focal length F were adjusted by adjusting X ₄ and X ₅ . That is, between these
M = (X ₃ + X ₄ ) / X ₅ ,
1 / F = 1 / (X ₃ + X ₄ ) + 1 / X ₅ ,
There is a relationship. The optical path total length X ₆ was about 1.3m in this embodiment.

レ ー ザ ー The laser processing ability has been dramatically improved by using such a long and narrow beam. In other words, the strip-shaped beam exits the optical system 44 and then irradiates the sample 51 via the total reflection mirror 49. However, since the width of the beam is substantially equal to or longer than the width of the sample, the beam ends up. The sample need only be moved in one direction. Accordingly, the sample stage and the driving device 50 have a simple structure and are easy to maintain. In addition, the positioning operation (alignment) when setting the sample is also easy. In the present invention, it is only necessary to have a function of rotating the sample in addition to the movement in one direction.

On the other hand, if the beam is nearly square, it is impossible to cover the entire surface of the substrate by itself, so the sample must be moved two-dimensionally in the vertical and horizontal directions. However, in that case, the driving device of the stage becomes complicated, and it is difficult to perform positioning in two dimensions. In particular, when the alignment is performed manually, time loss in the process is large and productivity is reduced. These devices need to be fixed on a stable base 41 such as an anti-vibration table.

The above-described laser device may be configured alone, or may be combined with other devices such as a plasma CVD film forming device, an ion implantation device (or ion doping device), a thermal annealing device, and other semiconductor manufacturing devices. A combined multi-chamber may be used.

In this embodiment, a so-called monolithic AMLCD in which a peripheral circuit for driving an active matrix circuit is formed on the same substrate in an active matrix liquid crystal display device (AMLCD) will be described.

In such an apparatus, as shown in FIG. 1A, an area 14 of an active matrix circuit, a column driver 13 and a scan driver 12 are provided on the edge of the substrate 11. Actually, at this stage of laser irradiation, as is clear from the above process, there is only a uniform film on the substrate, but for simplicity, the position where the circuit is formed is shown. . Although both the column driver 13 and the scan driver 12 have shift registers, since the column driver outputs an analog signal, an amplifier (buffer circuit) for that is included.

の う ち Among the elements used in such an AMLCD, the outline of the manufacturing process of the thin film transistor was as follows.

[1] Formation of a base silicon oxide film and an amorphous silicon film on a glass substrate and / or application of a crystallization accelerator (eg, nickel acetate, etc.) on the amorphous silicon film [2] Crystallization of amorphous silicon film by solid phase growth (example of solid phase growth conditions: 550 ° C., 8 hours, nitrogen atmosphere)
[3] Laser treatment of crystallized silicon film (for the purpose of improving crystallinity)
[4] Formation of island-like silicon region by etching of silicon film [5] Formation of gate insulating film (silicon oxide) [6] Formation of gate electrode [7] Source / drain by implantation of impurity element (phosphorus, boron, etc.) [8] Activation of implanted impurities by laser irradiation [9] Formation of interlayer insulator [10] Formation of electrodes on source / drain

(4) In this embodiment and the following embodiments 2 and 3, the above process relates to the laser light irradiation of [3] performed for the purpose of further improving the crystallinity of the polycrystalline silicon film.

FIG. 1 shows a laser processing step of this embodiment. In the present embodiment, the laser beam 15 has a size sufficient to irradiate the entire column driver 13, and is, for example, a rectangle having a width of 10 mm and a length of 300 mm. First, as shown in FIG. 1B, the substrate was moved so that the column driver was irradiated with laser light. At this stage, the substrate is not irradiated with laser light. Thereafter, the laser beam was irradiated without substantially moving the laser beam and the substrate. Laser light irradiation was performed in the air, and the substrate temperature was 200 ° C. As a laser, a KrF excimer laser (wavelength: 248 nm) was used. The laser oscillation frequency was 10 Hz, the energy density of the laser light was 300 mJ / cm ^ (2), and the laser light pulse was 10 shots. When the required number of shots of laser light irradiation were completed, the laser light irradiation was stopped. (FIG. 1 (B))

(4) Thereafter, the position to be irradiated with the laser beam was shifted downward, and the substrate was moved to a position where the active matrix region 14 and the upper end of the scan driver 12 were exposed to the laser beam 15. (Fig. 1 (C))

Then, the substrate was moved while irradiating a laser beam. For example, the oscillation frequency of the laser was 10 Hz, the energy density of the laser light was 300 mJ / cm ² , and the scanning speed of the laser light was 10 mm / s. As a result, the laser beam 15 is shifted by 1 mm. Since the width of the beam is 10 mm, about 10 shots of laser light are irradiated at one location. (Fig. 1 (D))

レ ー ザ ー Thus, the laser was scanned to the lower end of the substrate, and the scan driver 12 and the active matrix area 14 were irradiated with laser light. (FIG. 1 (E))

で は In this example, there was no laser beam overlap in the column driver 13. As a result, the threshold voltage of the thin film transistor in the column driver became very small, and was typically 0.01 V or less in the adjacent thin film transistor and 0.05 V or less in the column driver. Other characteristics were similar. On the other hand, the laser beam overlapped between the scan driver 12 and the active matrix area 14. Therefore, for example, the variation in the threshold voltage of the thin film transistor in the scan driver 12 was about 0.1 V for the adjacent thin film transistors, and was about the same in the plane. The same applies to the active matrix region 14. However, this degree of variation did not hinder the operation of each circuit.

FIG. 2 shows a laser processing step of this embodiment. Also in this embodiment, the laser beam 25 has a size sufficient to irradiate the entire column driver 23, and is, for example, a rectangle having a width of 10 mm and a length of 200 mm. First, as shown in FIG. 2B, the substrate was moved so that the column driver was irradiated with laser light. At this stage, the substrate is not irradiated with laser light. Thereafter, the laser beam was irradiated without substantially moving the laser beam and the substrate. Laser light irradiation was performed in the air, and the substrate temperature was 200 ° C. As a laser, a KrF excimer laser (wavelength: 248 nm) was used. The oscillation frequency of the laser was 10 Hz, the energy density of the laser light was 300 mJ / cm ² , and the pulse of the laser light was 10 shots. When the required number of shots of laser light irradiation were completed, the laser light irradiation was stopped. (FIG. 2 (B))

(4) Thereafter, the position to be irradiated with the laser beam was shifted downward, and the substrate was moved to a position where the upper end of the active matrix area 24 was exposed to the laser beam 25. Note that, unlike the first embodiment, the scan driver 22 is not irradiated with laser light at this time. (Fig. 2 (C))

Then, the substrate was moved while irradiating a laser beam. For example, the oscillation frequency of the laser was 10 Hz, the energy density of the laser light was 250 mJ / cm ² , and the scanning speed of the laser light was 10 mm / s. As a result, the laser beam 25 shifts by 1 mm. Since the width of the beam is 10 mm, about 10 shots of laser light are irradiated at one location. (FIG. 2 (D))

、 Thus, the laser was scanned to the lower end of the substrate, and the active matrix region 24 was irradiated with the laser beam. (FIG. 2 (E))

Thereafter, the substrate was rotated by １ ／. In FIG. 2F, a dotted square 26 is the position of the first substrate. (FIG. 2 (F))

Then, as shown in FIG. 2G, the substrate was moved so that the scan driver 22 was irradiated with laser light. At this stage, the laser beam is not irradiated to the substrate. Thereafter, the scan driver 22 was irradiated with laser light without substantially moving the laser beam and the substrate. The oscillation frequency of the laser was 10 Hz, the energy density of the laser light was 300 mJ / cm ² , and the pulse of the laser light was 10 shots. When the required number of shots of laser light irradiation were completed, the laser light irradiation was stopped. (Fig. 2 (G))

In this embodiment, not only the column driver 23 but also the scan driver 22 did not overlap with the laser beams. In this embodiment, the driver circuit irradiates a laser beam of 300 mJ / cm ² , whereas the active matrix circuit irradiates a laser beam of 250 mJ / cm ² . This is to obtain a thin film transistor having a small leakage current (leakage current when a reverse bias voltage is applied to the gate; also referred to as off-state current) in the active matrix circuit. On the other hand, in the driver circuit, since high-speed operation of the thin film transistor is required, the energy of the laser beam is increased to obtain high mobility.

FIG. 3 shows a laser processing step of the present embodiment. In the present embodiment, unlike the first and second embodiments, the present invention relates to a monolithic liquid crystal display having driver circuits on the upper, lower, left, and right sides of the substrate. [8] Activation of implanted impurities by laser irradiation ”).

FIG. 6 shows an outline of the entire process of the substrate to be processed according to the present embodiment. First, a silicon oxide film having a thickness of 100 to 500 nm, for example, 200 nm was formed as a base oxide film 102 on a substrate (Corning 7059, 300 mm × 200 mm) 101. As a method of forming the oxide film, a sputtering method in an oxygen atmosphere was used. However, in order to further improve mass productivity, TEOS may be formed by decomposition and deposition by plasma CVD. Further, the silicon oxide film thus formed may be annealed at 400 to 650 ° C.

After that, an amorphous silicon film is deposited in a thickness of 30 to 500 nm, preferably 40 to 100 nm, for example, 50 nm by a plasma CVD method or an LPCVD method, and left in a reducing atmosphere at 550 to 600 ° C. for 8 to 24 hours. Crystallized. In that case, crystallization may be promoted by adding a trace amount of a metal element such as nickel which promotes crystallization. This step may be performed by laser irradiation. Then, the silicon film crystallized in this manner was etched to form the island region 103. Further, a silicon oxide film 104 having a thickness of 70 to 150 nm, for example, 120 nm was formed thereon by a plasma CVD method.

Thereafter, an aluminum (containing 1 wt% Si or 0.1 to 0.3 wt% Sc (scandium)) film having a thickness of 100 nm to 3 μm, for example, 500 nm is formed by a sputtering method, and this is etched. A gate electrode 105 and a gate wiring 106 were formed. (FIG. 6 (A))

{Circle around (2)} Then, anodization was performed on the gate electrode 105 and the gate electrode 106 by passing an electric current in an electrolytic solution to form anodic oxides 107 and 108 having a thickness of 50 to 250 nm, for example, 200 nm. The electrolytic solution used was prepared by diluting L-tartaric acid in ethylene glycol at a concentration of 5% and adjusting the pH to 7.0 ± 0.2 using ammonia. The substrate 101 is immersed in the solution, the + side of the constant current source is connected to the gate wiring on the substrate, the platinum electrode is connected to the-side, and a voltage is applied at a constant current of 20 mA to reach 150 V. Oxidation was continued until complete. Further, the oxidation was continued at a constant voltage of 150 V until the current became 0.1 mA or less. As a result, an aluminum oxide film having a thickness of 200 nm was obtained.

Thereafter, impurities (here, phosphorus) are implanted into the island-shaped silicon film 103 in a self-aligned manner by using the gate electrode portion (that is, the gate electrode and the anodic oxide film around the gate electrode) as a mask by ion doping. ), A low concentration impurity region (LDD) 109 was formed. The dose was 1 × 10 ^{13 to} 5 × 10 ¹⁴ atoms / cm ² and the acceleration voltage was 10 to 90 kV. For example, the dose was 5 × 10 ¹³ atoms / cm ² and the acceleration voltage was 80 kV. (FIG. 6 (B))

{Circle around (2)} Then, a silicon oxide film 110 was deposited by the plasma CVD method. Here, TEOS and oxygen, or monosilane and nitrous oxide were used as source gases. The optimum value of the thickness of the silicon oxide film 110 differs depending on the height of the gate electrode and the wiring. For example, when the height of the gate electrode / wiring is about 600 nm including the anodic oxide film as in the present embodiment, it is preferably 1/3 to 2 times as large as 200 nm to 1.2 μm. And In this film forming step, it is required that both the uniformity of the film thickness in the flat portion and the step coverage be good. As a result, the thickness of the silicon oxide film on the side surface of the gate electrode / wiring is increased by the amount indicated by the dotted line in FIG. (FIG. 6 (C))

Next, the silicon oxide film 108 was etched by performing anisotropic dry etching by a known RIE method. This etching is completed when the etching reaches the gate insulating film 105. The end point of such etching can be controlled, for example, by making the etching rate of the gate insulating film 105 smaller than that of the silicon oxide film 110. Through the above steps, substantially triangular insulators (sidewalls) 111 and 112 remain on the side surfaces of the gate electrode and wiring.

Thereafter, phosphorus was introduced again by the ion doping method. In this case, the dose is preferably 1 to 3 digits larger than the dose in the step of FIG. In this embodiment, the dose is set to 2 × 10 ¹⁵ atoms / cm ^{2, which} is 40 times the dose of the first phosphorus doping. The acceleration voltage was 80 kV. As a result, a region (source / drain) 114 into which high-concentration phosphorus was introduced was formed, and a low-concentration region (LDD) 113 was left below the sidewall. (FIG. 6 (D))

Further, irradiation with a KrF excimer laser (wavelength: 248 nm, pulse width: 20 nsec) activated the doped impurities. The energy density of the laser was 200 to 400 mJ / cm ² , preferably 250 to 300 mJ / cm ² . (FIG. 6E)

(4) Finally, a silicon oxide film having a thickness of 500 nm was formed on the entire surface as an interlayer insulator 115 by a CVD method. Then, contact holes were formed in the source / drain of the TFT, and aluminum wiring / electrodes 116 and 117 of the second layer were formed. The thickness of the aluminum wiring was about 400 to 600 nm, almost the same as the gate electrode and wiring.

ＴＦＴThrough the above steps, a TFT having an N-channel LDD was completed. Hydrogen annealing may be further performed at 200 to 400 ° C. to activate the impurity region. In the second-layer wiring 117, the step at the portion over the gate wiring 106 is moderated by the presence of the sidewall 112, so that the thickness of the second-layer wiring is almost the same as the gate electrode / wiring. Regardless, almost no break was observed. (FIG. 6 (F))

Note that, among the above steps, the step of activating the doping impurities by laser irradiation in FIG. 6E is described below.

Next, the outline of the configuration of the substrate to be processed in this embodiment will be described. FIG. 7 shows an outline of a cross section of the substrate processed in this embodiment. The substrate is provided with a peripheral drive circuit region and a pixel circuit region. The peripheral drive circuit is formed by NMOS and PMOS TFTs, and the pixel circuit is formed by PMOS TFTs. Note that a pixel electrode is provided in the TFT of the pixel circuit. (FIG. 7)

FIG. 3 shows a state of the substrate to be processed in the present embodiment viewed from above. As apparent from FIG. 6E, no interlayer insulator, second-layer wiring, and the like are formed in the steps described below. As shown in FIG. 3A, scan drivers 32 and 33, column drivers 34 and 35, and an active matrix circuit 36 are formed on a substrate 31. Also in this embodiment, the laser beam 37 has a size enough to irradiate the entire column drivers 34 and 35, and is, for example, a rectangle having a width of 10 mm and a length of 300 mm.

First, as shown in FIG. 3B, the substrate was moved so that the scan driver 32 was irradiated with laser light. At this stage, the substrate is not irradiated with laser light. Thereafter, the laser beam was irradiated without substantially moving the laser beam and the substrate. Laser light irradiation was performed in the air, and the substrate temperature was 200 ° C. As a laser, a KrF excimer laser (wavelength: 248 nm) was used. The oscillation frequency of the laser was 10 Hz, the energy density of the laser light was 300 mJ / cm ² , and the pulse of the laser light was 10 shots. When the required number of shots of laser light irradiation were completed, the laser light irradiation was stopped. (FIG. 3 (B))

Thereafter, the substrate was moved, and the scan driver 33 was set to be irradiated with the laser beam. The laser irradiation was performed again without moving the substrate and the laser beam. Also in this case, 10 shots of laser light were irradiated under the same conditions as above. When the required number of shots of laser light were irradiated, the laser light irradiation was stopped. (FIG. 3 (C))

Thereafter, the substrate was rotated by １ ／. In FIG. 3D, the dotted square 38 is the position of the first substrate. (FIG. 3 (D))

(4) Thereafter, as shown in FIG. 3E, the substrate was moved so that the column driver 34 was irradiated with a laser beam. Then, the laser beam was irradiated without moving the laser beam and the substrate substantially. The irradiation conditions at this time were the same as above, and the laser light pulse was 10 shots. When the required number of shots of laser light irradiation were completed, the laser light irradiation was stopped. (FIG. 3 (E))

Next, the position to be irradiated with the laser light was shifted downward, and the substrate was moved to a position where the upper end of the active matrix area 36 (and the scan drivers 32 and 33) was applied to the laser beam 37. Then, the substrate was moved while irradiating a laser beam. For example, the oscillation frequency of the laser was 10 Hz, the energy density of the laser light was 250 mJ / cm ² , and the scanning speed of the laser light was 10 mm / s. As a result, the laser beam 25 shifts by 1 mm. Since the width of the beam is 10 mm, about 10 shots of laser light are irradiated at one location. (FIG. 3 (F))

レ ー ザ ー Thus, the laser was scanned to the lower end of the active matrix circuit 36 and the active matrix area 36 was irradiated with the laser beam. Laser irradiation was stopped when irradiation to the lower end of the active matrix was completed.

Then, as shown in FIG. 3G, the substrate was moved so that the laser light was irradiated on the column driver 35. Then, the column driver 35 was irradiated with laser light without substantially moving the laser beam and the substrate. The oscillation frequency of the laser was 10 Hz, the energy density of the laser light was 300 mJ / cm ² , and the pulse of the laser light was 10 shots. When the required number of shots of laser light irradiation were completed, the laser light irradiation was stopped. (Fig. 3 (G))

で は In this example, the laser beams did not overlap at all in the column drivers 34 and 35. On the other hand, in the scan driver, the laser beams did not overlap in the laser light irradiation process shown in FIGS. 3B and 3C, but did occur during the laser irradiation of the active matrix circuit. However, the scan driver is substantially less restrictive in terms of characteristic variation than the column driver, and the energy of laser light irradiation on the active matrix circuit is smaller than the energy of the first laser irradiation. There was no effect.

1 shows a laser processing method of an example. (See Example 1) 1 shows a laser processing method of an example. (See Example 2) 1 shows a laser processing method of an example. (See Example 3) FIG. 1 shows a conceptual diagram of a laser annealing apparatus used in an example. FIG. 2 shows a conceptual diagram of an optical system of a laser annealing apparatus used in the example. The outline of the manufacturing process of the TFT element of the example is shown. (See Example 3) 2 shows a cross section of a TFT circuit. (See Example 3)

Explanation of reference numerals

11, 21, 31 Substrate 12, 22, 32, 33 Scan driver 13, 23, 34, 35 Column driver 14, 24, 36 Active matrix circuit area 15, 25, 37 Laser beam spot (linear laser beam)
26, 38 Indicates the position of the substrate before rotation.

Claims (5)

A source driver circuit having a plurality of TFTs,
A gate driver circuit having a plurality of TFTs,
An active matrix circuit driven by the source driver circuit and the gate driver circuit and having a plurality of TFTs;
In a method for manufacturing an active matrix display device having on the same substrate,
Forming an amorphous silicon film on the substrate,
Crystallizing the amorphous silicon film to form a crystalline silicon film,
Irradiating the crystalline silicon film in a region where the source driver circuit, the gate driver circuit and the active matrix circuit are formed with a linear or rectangular laser light;
Using the crystalline silicon film, the source driver circuit, the gate driver circuit and the active matrix circuit to form an island region of each of the plurality of TFTs,
A source region and a drain region are respectively formed in the island regions of the plurality of TFTs of the source driver circuit, the gate driver circuit, and the active matrix circuit;
The source driver circuit, the gate driver circuit and the active matrix circuit by annealing the island region of each of the plurality of TFTs, to activate the source region and the drain region,
The linear or rectangular laser light for the crystalline silicon film in the region where the source driver circuit is formed is a laser light having a size sufficient to irradiate the entire region where the source driver circuit is formed, And, without moving the substrate and the laser light, irradiate the area where the source driver circuit is formed,
The linear or rectangular laser light for the crystalline silicon film in a region where the gate driver circuit and the active matrix circuit are formed is a laser having a size enough to irradiate the entire region where the source driver circuit is formed. A method for manufacturing an active matrix display device, which is light and irradiates a region where the gate driver circuit and the active matrix circuit are to be formed while moving the substrate and the laser beam. A source driver circuit having a plurality of TFTs,
A gate driver circuit having a plurality of TFTs,
An active matrix circuit driven by the source driver circuit and the gate driver circuit and having a plurality of TFTs;
In the method for producing an active matrix display device having on the same substrate,
Forming an amorphous silicon film on the substrate,
Crystallizing the amorphous silicon film to form a crystalline silicon film,
Using the crystalline silicon film, an island region is formed in each of the plurality of TFTs of the source driver circuit, the gate driver circuit, and the active matrix circuit,
A source region and a drain region are respectively formed in the island regions of the plurality of TFTs of the source driver circuit, the gate driver circuit, and the active matrix circuit;
The source region and the drain region of each of the plurality of TFTs of the source driver circuit, the gate driver circuit and the active matrix circuit are activated by being irradiated with linear or rectangular laser light,
The linear or rectangular laser light with respect to the island region of the region where the source driver circuit is formed is a laser beam having a size sufficient to irradiate the entire region where the source driver circuit is formed, and Irradiating the region where the source driver circuit is formed without moving the substrate and the laser light,
The linear or rectangular laser light for the island region of the region where the gate driver circuit and the active matrix circuit are formed is a laser light having a size sufficient to irradiate the entire region where the source driver circuit is formed. And irradiating a region where the gate driver circuit and the active matrix circuit are formed while moving the substrate and the laser beam. In claim 1 or claim 2,
The method for manufacturing an active matrix display device, wherein the laser beam is a KrF excimer laser. In any one of claims 1 to 3,
The method for manufacturing an active matrix display device, wherein the crystalline silicon film is formed by crystallizing the amorphous silicon film using a metal element. In any one of claims 1 to 4,
A method of manufacturing an active matrix display device, comprising performing hydrogen annealing at 200 to 400 ° C. after performing the activation.

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