JP6387855B2 - Manufacturing method of silicon carbide semiconductor device and laser processing apparatus used therefor - Google Patents

Description

  The present invention relates to a method of manufacturing an SiC semiconductor device capable of realizing ohmic contact of electrodes formed on a semiconductor element using silicon carbide (hereinafter referred to as SiC) as a semiconductor material, and a laser processing apparatus used therefor. .

  Conventionally, when a vertical power device is formed on a SiC substrate, in order to reduce the resistance in the thickness direction of the substrate, after forming the device on the surface side of the SiC substrate, the SiC substrate is thinned from the back side, It has been studied to form an ohmic electrode on the back side of the SiC substrate. When the ohmic electrode is formed after the SiC substrate is thinned, it is necessary to locally heat only the back surface in order to prevent thermal damage to the device on the front surface side. In recent years, a laser annealing technique has been used as such a local heating method (see, for example, Patent Document 1).

  On the other hand, after an ohmic electrode is formed on the back side of the SiC substrate, a dicing process for forming chips is performed. As a dicing method, a blade method is conventionally used, but in recent years, a laser dicing technique using a laser beam has begun to be used.

JP 2009-283754 A

  When an ohmic electrode is formed on the back side of the SiC substrate using laser annealing technology, a laser having a wavelength that does not transmit through the SiC substrate is used so as not to cause thermal damage to the device formed on the front side of the SiC substrate. .

  On the other hand, when a SiC substrate on which a device is formed is diced by a laser dicing technique, a laser having a wavelength that passes through the SiC substrate is used to generate a starting point inside the substrate.

  Since both laser annealing technology and laser dicing technology use laser light, it is preferable that a common laser processing apparatus can be applied. However, as described above, the laser annealing technology uses laser light having a wavelength that does not pass through the SiC substrate, and the laser dicing technology uses laser light having a wavelength that passes through the SiC substrate. It is necessary to use a separate laser processing apparatus.

  In view of the above points, the present invention provides a method of manufacturing an SiC semiconductor device capable of performing laser annealing and laser dicing based on a laser processing apparatus using a common laser generator, and a laser processing apparatus used therefor. Objective.

In order to achieve the above object, according to the first aspect of the present invention, an SiC semiconductor substrate (1) on which at least a part of the components of the semiconductor element is formed is prepared, and a metal thin film (on the back surface of the SiC semiconductor substrate) 110) forming a metal thin film, and after the metal thin film forming step, the metal thin film is irradiated with laser light and subjected to laser annealing to form an ohmic electrode (11). A dicing step of dividing the SiC semiconductor substrate on which the ohmic electrode is formed by performing laser dicing by performing laser dicing in the dicing region after the electrode forming step, and in the electrode forming step and the dicing step, A laser (38) having a predetermined wavelength is generated using a common laser generator (31), and at least an electrode is formed. In one of the steps and the dicing process, the wavelength of the laser generated by the laser generating unit is converted by the wavelength conversion unit (36, 37), and the laser beam (51) having a wavelength that does not transmit SiC in the electrode forming process is used. an annealing, have rows of laser dicing by a laser beam having a wavelength transmitted through the SiC in the dicing step, the electrode forming step and the dicing step is characterized to be performed successively using a common laser generator.

  In this way, the wavelength of the laser generated by the laser generator is converted by the wavelength conversion unit so that the wavelength can be applied to each of laser annealing and laser dicing. As a result, it is possible to perform laser annealing and laser dicing based on a laser processing apparatus using one common laser generator. Therefore, it is possible to simplify the equipment and reduce the capital investment cost.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows an example of a corresponding relationship with the specific means as described in embodiment mentioned later.

It is a figure which shows the cross-sectional structure of the planar type MOSFET manufactured by the manufacturing method of the SiC semiconductor device concerning 1st Embodiment of this invention. It is the perspective view which showed the manufacturing process of the SiC semiconductor device. It is sectional drawing which showed a part of manufacturing process of the SiC semiconductor device. It is sectional drawing of the laser processing apparatus which performs laser annealing and laser dicing. It is sectional drawing which showed a part of manufacturing process of the SiC semiconductor device concerning 2nd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments, parts that are the same or equivalent to each other will be described with the same reference numerals.

(First embodiment)
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments shown in the drawings will be described below. First, the configuration of a planar type vertical power MOSFET as a semiconductor element manufactured by the method of manufacturing an SiC semiconductor device shown in the present embodiment will be described with reference to FIG. This SiC semiconductor device is suitable when applied to, for example, an inverter.

The vertical power MOSFET is formed using an n ⁺ type SiC substrate (hereinafter referred to as an n ⁺ type substrate) 1. The n ⁺ -type SiC substrate 1 has a main surface 1a as an upper surface and a back surface 1b as a lower surface opposite to the main surface 1a, and is made of single crystal SiC. The n ⁺ a on the main surface 1a -type SiC substrate 1, which is constituted by SiC having a lower dopant concentration than the n ⁺ -type SiC substrate 1 n ^- -type epitaxial layer (hereinafter, n ^- type called epi layer) 2 Are stacked.

In a predetermined region in the surface layer portion of the n ⁻ -type epi layer 2, p ⁻ -type base regions 3 a and 3 b having a predetermined depth are formed apart from each other. The p ⁻ -type base regions 3a and 3b are provided with deep base layers 30a and 30b that are partially thickened. The deep base layers 30a and 30b are formed in portions that do not overlap the n ⁺ -type source regions 4a and 4b. In the p ⁻ -type base regions 3a and 3b, the thick portion where the deep base layers 30a and 30b are formed has a higher impurity concentration than the thin portion where the deep base layers 30a and 30b are not formed. It is dark.

Such deep base layers 30a and 30b reduce the thickness of the n ⁻ type epi layer 2 below the deep base layers 30a and 30b, and shorten the distance between the n ⁺ type SiC substrate 1 and the deep base layers 30a and 30b. Become. Thereby, the electric field strength between n ⁺ type SiC substrate 1 and deep base layers 30a and 30b can be increased, and avalanche breakdown can be easily performed.

p ^- is a predetermined region in the surface layer of type base region 3a, the p ^- shallow n ⁺ -type source region 4a is formed than type base region 3a. Further, p ^- type in a predetermined region in the surface layer of the base region 3b, the p ^- shallow n ⁺ -type source region 4b than type base region 3b is formed.

Further, n ⁻ -type layer 5a and n ⁺ -type layer 5b are formed on the surface of n ⁻ -type epi layer 2 and p ⁻ -type base regions 3a and 3b between n ⁺ -type source region 4a and n ⁺ -type source region 4b. An n-type SiC layer 5 made of is extended. That is, the n-type SiC layer 5 is arranged so as to connect the source regions 4a and 4b and the n ⁻ -type epi layer 2 at the surface portions of the p ⁻ -type base regions 3a and 3b. The n-type SiC layer 5 functions as a channel formation layer on the device surface during device operation. Hereinafter, the n-type SiC layer 5 is referred to as a surface channel layer.

The surface channel layer 5 is formed, for example, by ion-implanting n-type impurities into the surface portions of the n ⁻ -type epi layer 2 and the p ⁻ -type base regions 3a and 3b. Type base region 3a, n located on the top of 3b ^{- -} p of the surface channel layer 5 dopant concentration type layer 5a is, n ^- -type epitaxial layer 2 and the p ^- type base region 3a, the dopant concentration of 3b below and It has become. Further, n ^- dopant concentration of the n ⁺ -type layer 5b formed on the surface portion of the type epi layer 2, n ^- is the higher concentration than the type epi layer 2. Thereby, low on-resistance is achieved.

Also, recesses 6a and 6b are formed in the surface portions of the p ⁻ type base regions 3a and 3b and the n ⁺ type source regions 4a and 4b, and a deep base layer having a high p type impurity concentration from the bottom of the recesses 6a and 6b. 30a and 30b are exposed.

A gate insulating film (silicon oxide film) 7 is formed on the upper surface of the surface channel layer 5 and the upper surfaces of the n ⁺ -type source regions 4a and 4b. Further, a gate electrode 8 is formed on the gate insulating film 7, and the gate electrode 8 is covered with an insulating film 9. As the insulating film 9, a silicon oxide film is used. A source electrode 10 is formed thereon, and the source electrode 10 is connected to the n ⁺ type source regions 4a and 4b and the p ⁻ type base regions 3a and 3b. A drain electrode 11 is formed on the back surface 1 b of the n ⁺ -type SiC substrate 1. The drain electrode 11 is formed of an ohmic electrode that is in ohmic contact with the back surface 1 b of the n ⁺ -type SiC substrate 1.

  In the above structure, the drain electrode 11 corresponds to the ohmic electrode of the present invention.

  Next, a method for manufacturing the vertical power MOSFET shown in FIG. 1 will be described. However, since the basic manufacturing method of the vertical power MOSFET according to this embodiment is the same as the conventional method, a method for forming the drain electrode 11 different from the conventional method will be mainly described.

  The vertical power MOSFET according to the present embodiment is manufactured through the manufacturing steps shown in FIG.

First, as shown in FIG. 2A, for example, an n ⁺ type SiC substrate 1 having a thickness of 350 μm is prepared. The n ⁺ type SiC substrate 1 is manufactured, for example, by slicing and polishing a SiC ingot doped with an n-type impurity.

Next, as shown in FIG. 2B, a device forming process is performed in which at least a part of the constituent elements of the semiconductor element is formed on the surface side of the n ⁺ type SiC substrate 1. That is, after the n ⁻ type epi layer 2 is epitaxially grown, the ion implantation using a mask (not shown) is performed to form the p ⁻ type base regions 3a and 3b and the deep base layers 30a and 30b, the n ⁺ type source region 4a, The formation process of 4b and the formation process of the surface channel layer 5 are performed. Further, a device in which each component of the vertical power MOSFET is formed as a device by performing a forming process of the gate insulating film 7, a forming process of the gate electrode 8, a forming process of the insulating film 9, a forming process of the source electrode 10, and the like. A formation substrate 15 is formed.

Thereafter, as shown in FIG. 2C, the device forming substrate 15 is mounted on the support substrate 20. At this time, the n ⁺ -type SiC substrate 1 is arranged so that the surface side thereof, that is, one surface on which the device is formed faces the support substrate 20 side. Subsequently, as shown in FIG. 2D, a part of the back surface side of the device forming substrate 15, that is, the back surface 1b side of the n ⁺ -type SiC substrate 1 is removed by grinding and polishing, as indicated by a broken line in the drawing. The n ⁺ type SiC substrate 1 is thinned.

Next, in the steps shown in FIGS. 2E to 2G, a step of forming the drain electrode 11 on the back surface 1b of the n ⁺ -type SiC substrate 1 after the thinning and a dicing step of dividing into chips are performed. The details of the steps shown in FIGS. 2E to 2G will be described with reference to FIG. In practice, the device is formed on the surface 1a side of the n ⁺ type SiC substrate 1 to form the device forming substrate 15. However, in FIG. 3, only the n ⁺ type SiC substrate 1 is shown without showing the device. This is a simplified illustration.

First, as the process shown in FIG. 2E, the processes shown in FIGS. Specifically, as shown in FIG. 3B, a metal thin film 110 is formed on the back surface 1b of the n ⁺ type SiC substrate 1 after thinning shown in FIG. 3A (metal thin film forming step). . For example, by depositing Ni on the n ⁺ -type SiC substrate 1 on the back surface 1b, forming a metal thin film 110 on the n ⁺ -type SiC substrate 1 on the back surface 1b.

In the subsequent step shown in FIG. 3C, laser annealing is performed by irradiating the metal thin film 110 with laser light (electrode formation step). For example, the device forming substrate 15 is scanned on the XY plane while scanning using a solid-state laser such as an LD-excited solid-state laser, and the laser beam 51 is irradiated on the back surface 1b side of the n ⁺ -type SiC substrate 1. Thereby, laser light irradiation is performed in units of chips. Then, the metal (Ni in the present embodiment) constituting the metal thin film 110 and Si contained in the n ⁺ type SiC substrate 1 are reacted to form a silicide, thereby forming the alloy layer 111 shown in FIG. Can be generated. This alloy layer 111 can constitute the drain electrode 11 made of an ohmic electrode. Thus, by performing local annealing by laser annealing, it becomes possible to make the drain electrode 11 an ohmic electrode by a low-temperature process that can suppress a high temperature in a region not irradiated with laser. For this reason, it becomes possible to suppress the influence on the device formed on the surface 1a side of the n ⁺ type SiC substrate 1.

Next, as a step shown in FIG. 2 (f), the dicing tape 21 is attached to the back surface of the device forming substrate 15, that is, the back surface 1 b side of the n ⁺ type SiC substrate 1, that is, the drain electrode 11.

Then, laser dicing is performed as a step shown in FIG. Specifically, for example, by scanning the device forming substrate 15 on the XY plane while scanning using a solid-state laser, the laser light 52 is caused to pass along the dicing line as shown in FIG. Irradiation is performed to divide the n ⁺ type SiC substrate 1 into chips. Thereby, the SiC semiconductor device having the vertical power MOSFET is completed.

  At this time, the laser beam 51 used for annealing the drain electrode 11 by laser annealing shown in FIG. 3C and the laser beam 52 used when dividing into chips by laser dicing shown in FIG. It is generated by the same laser processing device.

As shown in FIG. 4, a laser processing apparatus 30 that performs laser annealing and laser dicing includes a laser oscillator 31, a beam splitter 32, first to third reflection mirrors 33 to 35, and first and second wavelength conversion units 36 and 37. It is set as the structure provided with. Laser annealing and laser dicing are performed by irradiating the n ⁺ -type SiC substrate 1 disposed in the chamber 40 with the laser beams 51 and 52 using the laser processing apparatus 30.

The laser oscillator 31 corresponds to a laser generator, and generates laser beams 51 and 52 by, for example, generating a solid state laser 38. In this embodiment, the laser oscillator 31 has a wavelength of 1064 nm which becomes near infrared light. Is generated as a fundamental wave. The beam splitter 32 switches the solid laser 38 generated by the laser oscillator 31 to which of the first and second wavelength conversion units 36 and 37 is input. The first and second reflection mirrors 33 and 34 guide the solid-state laser 38 to the second wavelength conversion unit 37 or the n ⁺ -type in which the solid-state laser 38 output from the second wavelength conversion unit 37 is disposed in the chamber 40. It plays a role of guiding to the SiC substrate 1. The third reflecting mirror 35 plays a role of guiding the solid-state laser 38 output from the first wavelength conversion unit 36 to the n ⁺ -type SiC substrate 1 arranged in the chamber 40. The first and second wavelength conversion units 36 and 37 convert the input solid-state lasers 38 to different wavelengths and output them. In the case of the present embodiment, the first wavelength conversion unit 36 converts the wavelength of the solid-state laser having a wavelength of 1064 nm into the wavelength of visible light or near-infrared light, in this case, the wavelength of visible light of 532 nm which is a second harmonic. doing. By setting this wavelength, the solid-state laser 38 (laser beam 52) that transmits SiC can be obtained. The second wavelength conversion unit 37 converts the wavelength of the solid-state laser having the wavelength of 1064 nm into the wavelength of the ultraviolet light region, specifically, the wavelength of 355 nm to be the third harmonic or the wavelength of 266 nm to be the fourth harmonic. . By setting these wavelengths, the solid-state laser 38 (laser light 51) that does not transmit SiC can be obtained.

  In the chamber 40, the device forming substrate 15 on which the metal thin film 110 for forming the drain electrode 11 is formed is mounted on the XY stage 41. A plane parallel to the upper surface of the XY stage is taken as an XY plane, and the XY stage 41 can be scanned in the XY plane. Thereby, the device forming substrate 15 can be moved to a desired position on the XY plane when the laser beam irradiation is performed. Further, which of the first and second wavelength conversion units 36 and 37 is used to convert the wavelength of the solid-state laser 38 can be appropriately selected by controlling the beam splitter 32 by a control device (not shown).

  Using the laser processing apparatus configured as described above, the solid state laser 38 is transmitted through the incident window 42 such as quartz glass provided on one surface of the chamber 40 with respect to the device forming substrate 15 disposed in the chamber 40. Irradiate.

  That is, at the time of laser annealing, the beam splitter 32 is controlled so that the solid-state laser 38 is incident on the second wavelength conversion unit 37 side. As a result, the solid-state laser 38 is converted to a wavelength in the ultraviolet light region that does not transmit SiC, and laser light 51 is generated, which is irradiated onto the metal thin film 110 that constitutes the drain electrode 11. At this time, since the laser beam 51 is converted to a wavelength that does not transmit SiC, laser annealing can be performed without causing thermal damage to the device formed on the surface side of the device forming substrate 15.

  In laser dicing, the beam splitter 32 is controlled so that the solid-state laser 38 is incident on the first wavelength conversion unit 36 side. As a result, the solid-state laser 38 is converted to a wavelength in the visible light or near-infrared light region through which SiC is transmitted to generate the laser light 52 and irradiate the device forming substrate 15. At this time, since the laser beam 52 is converted to a wavelength that transmits SiC, a starting point is generated in the device forming substrate 15, laser dicing is performed along the dicing line, and the laser beam is divided into chips ( Dicing process).

  Thus, the SiC semiconductor device including the vertical power MOSFET shown in FIG. 1 according to the present embodiment is completed.

  In the manufacturing method of the present embodiment described above, the wavelength of the solid-state laser 38 generated by the laser oscillator 31 is converted by the first and second wavelength conversion units 36 and 37 so as to be applicable to laser annealing and laser dicing. . This makes it possible to perform laser annealing and laser dicing based on a laser processing apparatus using one common laser oscillator 31. Therefore, it is possible to simplify the equipment and reduce the capital investment cost.

(Second Embodiment)
A second embodiment of the present invention will be described. In this embodiment, the dicing process by radar dicing is changed with respect to the first embodiment, and the others are the same as those in the first embodiment. Therefore, only the parts different from the first embodiment will be described.

In the first embodiment, when laser dicing is performed, as shown in FIG. 2 (f), the back surface side of the device forming substrate 15, that is, the surface of the device forming substrate 15 is attached to the drain electrode 11 on the dicing tape 21. Dicing was performed by irradiating laser beam 52 on the surface. On the other hand, the step shown in FIG. 2 (f) is eliminated, and the laser beam 52 is irradiated from the back surface of the device forming substrate 15 (the front surface 1a of the n ⁺ -type SiC substrate 1) as shown in FIG. Dicing can also be performed.

  In this way, laser dicing can be performed by irradiating the laser beam 52 from the surface side of the device forming substrate 15. Thereby, the dicing process can be simplified. In addition, since there is no need to attach to a dicing tape before laser dicing, laser annealing and laser dicing can be performed continuously without taking out the device forming substrate 15 from the chamber 40. Therefore, it is possible to further simplify laser annealing and laser dicing.

(Other embodiments)
The present invention is not limited to the embodiment described above, and can be appropriately changed within the scope described in the claims.

  In the above embodiment, the solid-state laser 38 having a wavelength of 1064 nm, which is a near-infrared light region, is converted by the first wavelength conversion unit 36 into a wavelength of 532 nm, which is a double wave. However, since it is near infrared light having a wavelength of 1064 nm, the solid-state laser 38 generated by the laser oscillator 31 may be used as it is as the laser light 51 without using the first wavelength conversion unit 36. That is, the wavelength conversion unit that matches the wavelength of the laser beam 51 with the wavelength for performing either laser annealing or laser dicing, may be converted by the wavelength conversion unit, and may be adjusted to the other wavelength. May be used.

  The wavelength shown in the above embodiment is an example of the solid-state laser 38 generated by the laser oscillator 31. Further, although the solid laser 38 whose laser medium is solid is cited as an example of the laser beams 51 and 52, this is merely an example, and may be generated by another laser medium.

  In each of the above embodiments, the vertical power MOSFET has been described as an example. However, this is merely an example, and the present invention also relates to a method of manufacturing an SiC semiconductor device including other semiconductor elements such as a diode and an IGBT. It is possible to apply. In the case of a PN diode, at least one of an anode electrode and a cathode electrode is an ohmic electrode, and in the case of a Schottky diode, for example, the cathode electrode is an ohmic electrode. In the case of IGBT, the collector electrode is an ohmic electrode.

1 n ⁺ type substrate 1a main surface 1b back surface 10 source electrode 11 drain electrode 15 device forming substrate 31 laser oscillator 36, 37 first and second wavelength conversion unit 40 chamber 51, 52 laser beam 110 metal thin film 111 alloy layer

Claims (11)

A semiconductor having a silicon carbide semiconductor substrate (1) having a main surface (1a) and a back surface (1b) opposite to the main surface, and an ohmic electrode (11) formed on the back surface of the silicon carbide semiconductor substrate A silicon carbide semiconductor device having a device,
Preparing a silicon carbide semiconductor substrate on which at least a part of the constituent elements of the semiconductor element is formed, and forming a metal thin film (110) on the back surface of the silicon carbide semiconductor substrate;
After the metal thin film forming step, the metal thin film is silicided by irradiating laser light and performing laser annealing, and forming the ohmic electrode; and
A dicing step of dividing the silicon carbide semiconductor substrate on which the ohmic electrode is formed by performing laser dicing by performing laser beam irradiation in a dicing region after the electrode forming step;
In the electrode forming step and the dicing step, a laser (38) having a predetermined wavelength is generated using a common laser generating portion (31), and at least in the electrode forming step and the dicing step, the laser generating portion The wavelength of the laser generated by the laser beam is converted by a wavelength conversion unit (36, 37), and in the electrode forming step, the laser annealing is performed with a laser beam (51) having a wavelength that does not transmit silicon carbide, and the dicing step in have lines the laser dicing by laser light having a wavelength that passes through the silicon carbide,
The method of manufacturing a silicon carbide semiconductor device, wherein the electrode forming step and the dicing step are continuously performed using the common laser generator . In the electrode forming step and the dicing step, the silicon carbide semiconductor substrate after the formation of the ohmic electrode is irradiated with the laser light from the back side of the silicon carbide semiconductor substrate in the same chamber (41). The method for manufacturing a silicon carbide semiconductor device according to claim 1 , wherein the method is performed continuously. In the electrode forming step, the laser beam used for the laser annealing is one having a wavelength in the ultraviolet region,
3. The method for manufacturing a silicon carbide semiconductor device according to claim 1, wherein in the dicing step, a laser beam having a wavelength in a near infrared light or visible light region is used as the laser light used for the laser dicing. Wherein in the electrode forming step and the dicing step, the silicon carbide according to any one of claims 1 to 3, characterized in that a laser oscillator (31) for generating a solid laser (38) as said laser generator A method for manufacturing a semiconductor device. The fundamental wavelength of the solid-state laser is 1064 nm;
In the electrode formation step, the wavelength conversion unit (37) converts the wavelength of the solid laser, which is a third harmonic of 355 nm or a fourth harmonic of 266 nm, to be used as the laser light in the laser annealing. the method for manufacturing the silicon carbide semiconductor device according to any one of claims 1 to 4, wherein. The fundamental wavelength of the solid-state laser is 1064 nm;
In the dicing step, a fundamental wave of the solid-state laser or a laser beam converted to 532 nm, which is a second harmonic of the solid-state laser by the wavelength conversion unit (36), is used as the laser light in the laser dicing. A method for manufacturing a silicon carbide semiconductor device according to any one of claims 1 to 5 . A semiconductor having a silicon carbide semiconductor substrate (1) having a main surface (1a) and a back surface (1b) opposite to the main surface, and an ohmic electrode (11) formed on the back surface of the silicon carbide semiconductor substrate Used to manufacture a silicon carbide semiconductor device having an element,
A step of forming the ohmic electrode by performing laser annealing by laser light irradiation, and the silicon carbide semiconductor substrate on which the ohmic electrode is formed by performing laser dicing by performing laser light irradiation in a dicing region on a chip basis A laser processing apparatus used for both of the dividing steps,
A laser generator (31) for generating a laser (38);
When performing at least one of the laser annealing and the laser dicing, the wavelength of the laser generated by the laser generator is converted, so that laser light having a wavelength that does not transmit silicon carbide during the laser annealing (51 ) outputs, when the laser dicing example Bei wavelength conversion unit that outputs laser light having a wavelength that passes through the silicon carbide (52) (36, 37), and
A laser processing apparatus characterized in that the laser annealing and the laser dicing are continuously performed by using the laser generator in common . The wavelength conversion unit outputs a laser beam having a wavelength in the ultraviolet light region during the laser annealing, and the laser light in the near infrared light or visible light region during the laser dicing. The laser processing apparatus according to claim 7 , wherein a laser beam having a wavelength is output. 9. The laser processing apparatus according to claim 7 , wherein the laser generator is a laser oscillator (31) that generates a solid-state laser (38). The fundamental wavelength of the solid-state laser is 1064 nm;
In the laser annealing, the laser beam is converted into a wavelength of 355 nm, which is the third harmonic of the solid-state laser, or 266 nm, which is the fourth harmonic, by the wavelength conversion unit (37). The laser processing apparatus according to any one of claims 7 to 9 . The fundamental wavelength of the solid-state laser is 1064 nm;
In the laser dicing, the laser beam is converted into a fundamental wave of the solid-state laser or 532 nm which is a second harmonic of the solid-state laser by the wavelength conversion unit (36). The laser processing apparatus according to any one of claims 7 to 10 .

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