Method for manufacturing joined body

Abstract

This method for manufacturing a joined body comprises: a first step for disposing a glass layer between a first member and a ceramic second member; and a second step for joining the first member and the second member by melting the glass layer by irradiation with laser light after the first step. In the second step, irradiation with the laser light is performed such that, in an irradiation region, with the laser light, of the second member and the glass layer, the energy of the laser light incident on the second member without passing through the glass layer is made to be greater than the energy of the laser light incident on the glass layer.

Description

Manufacturing method of the bonded body

[0001] The present disclosure relates to a method for producing a bonded body.

[0002] A method for manufacturing a joined body is known in which a glass layer disposed between a first member and a second member made of ceramic is melted by sequentially irradiating the glass layer with a preheating laser beam and a main heating laser beam, thereby joining the first member and the second member (see, for example, Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2021-161013

[0004] However, in the manufacturing method of the bonded body as described above, unless the irradiation conditions (laser light output, irradiation time, irradiation timing, etc.) of the preheating laser light and the main heating laser light are strictly controlled, the bonding between the first member and the second member made of ceramic may become unstable.

[0005] Therefore, an object of the present disclosure is to provide a method for manufacturing a joined body that can easily and reliably join a first member and a second member made of ceramics.

[0006] A manufacturing method of a joined body according to one aspect of the present disclosure is [1] "a manufacturing method of a joined body comprising: a first step of arranging a glass layer between a first member and a second member made of ceramic; and a second step of, after the first step, joining the first member and the second member by irradiating laser light to melt the glass layer, wherein in the second step, the irradiation of the laser light is carried out such that, in an irradiated region of the laser light on the second member and the glass layer, the energy of the laser light incident on the second member without passing through the glass layer is greater than the energy of the laser light incident on the glass layer."

[0007] In the method for manufacturing a joined body described in [1] above, in the laser beam irradiation region of the second member and the glass layer, the laser beam is irradiated so that the energy of the laser beam incident on the second member without passing through the glass layer is greater than the energy of the laser beam incident on the glass layer. This allows the ceramic second member to be sufficiently heated in and around the laser beam irradiation region, thereby melting the glass layer. Therefore, the method for manufacturing a joined body described in [1] above allows the first member and the ceramic second member to be easily and reliably joined.

[0008] A manufacturing method of a bonded body according to one aspect of the present disclosure may be [2] "the manufacturing method of a bonded body according to the above [1], in which the laser light has a top-hat intensity distribution." According to the manufacturing method of a bonded body according to [2], even if the irradiation region of the laser light is slightly deviated from a desired position, it is possible to maintain a state in which the energy of the laser light incident on the second member without passing through the glass layer is greater than the energy of the laser light incident on the glass layer.

[0009] The manufacturing method of the joined body according to one aspect of the present disclosure may be [3] "the manufacturing method of the joined body according to the above [1] or [2], in which the ceramic is a ceramic that is absorptive to the laser beam." According to the manufacturing method of the joined body according to [3], the second member made of ceramic can be efficiently heated in the laser beam irradiated region and its vicinity.

[0010] A manufacturing method of a joined body according to one aspect of the present disclosure may be [4] "the manufacturing method of a joined body according to the above [1] or [2], in which the ceramic is a ceramic containing an additive material that is absorptive of the laser beam." According to the manufacturing method of a joined body according to [4], the second member made of ceramic can be efficiently heated in the laser beam irradiated region and its vicinity.

[0011] A manufacturing method of a bonded body according to one aspect of the present disclosure may be [5] "the manufacturing method of a bonded body according to any one of the above [1] to [4], wherein in the second step, the irradiation of the laser light is performed so that the optical axis of the laser light is inclined with respect to the thickness direction of the glass layer." According to the manufacturing method of a bonded body according to [5], at least a part of the region irradiated with the laser light can be easily and reliably positioned on the second member.

[0012] A manufacturing method of a bonded body according to one aspect of the present disclosure may be [6] "the manufacturing method of a bonded body according to the above [5], wherein in the second step, the irradiation of the laser light is performed such that the optical axis of the laser light is inclined from the irradiation region toward the center of the second member in all the irradiation regions." According to the manufacturing method of a bonded body according to [6], it is possible to reduce the size of an apparatus for irradiating the laser light, compared to a case where the apparatus is configured so that the optical axis of the laser light is inclined from the irradiation region toward the opposite side from the center of the second member.

[0013] A manufacturing method of a bonded body according to one aspect of the present disclosure may be [7] "the manufacturing method of a bonded body according to any one of the above [1] to [6], wherein in the second step, the laser beam scanning is performed by oscillating a galvanometer mirror that reflects the laser beam." According to the manufacturing method of a bonded body according to [7], the laser beam scanning according to the shape of the glass layer can be performed at high speed.

[0014] A manufacturing method of a bonded body according to one aspect of the present disclosure may be [8] "the manufacturing method of a bonded body according to any one of the above [1] to [7], wherein in the second step, the irradiation of the laser light is performed so that the irradiation region is located on the second member and on the glass layer." According to the manufacturing method of a bonded body according to [8], the glass layer can be melted in a shorter time than when the irradiation region of the laser light is located on the second member but not on the glass layer, and therefore the time required to bond the first member and the second member can be shortened.

[0015] A manufacturing method of a joined body according to one aspect of the present disclosure may be [9] "the manufacturing method of a joined body according to the above [8], wherein in the second step, the irradiation of the laser light is performed such that the energy of the laser light incident on the second member without passing through the glass layer is at least twice the energy of the laser light incident on the glass layer in the irradiation region." According to the manufacturing method of a joined body according to

[10] , the first member and the second member made of ceramics can be joined more easily and reliably.

[0016] A manufacturing method of a joined body according to one aspect of the present disclosure may be

[10] "the manufacturing method of a joined body according to any one of the above [1] to [7], wherein in the second step, the irradiation of the laser light is performed so that the irradiated region is located on the second member and not on the glass layer." According to the manufacturing method of a joined body according to [9], the glass layer can be melted in a state where the second member made of ceramic is more sufficiently heated compared to a case where the irradiated region of the laser light is located on both the second member and the glass layer, thereby improving the stability of the joining between the first member and the second member.

[0017] A manufacturing method of a bonded body according to one aspect of the present disclosure may be

[11] "the manufacturing method of a bonded body according to any one of the above [1] to

[10] , wherein in the second step, the irradiation of the laser light is performed such that an area of ​​a portion of the irradiation region located on the second member is larger than an area of ​​a portion of the irradiation region located on the glass layer." According to the manufacturing method of a bonded body according to

[11] , it is possible to more easily form a state in which the energy of the laser light incident on the second member without passing through the glass layer is larger than the energy of the laser light incident on the glass layer.

[0018] A manufacturing method of a joined body according to one aspect of the present disclosure may be

[12] "the manufacturing method of a joined body according to any one of the above [1] to

[11] , in which the first member is made of glass." In this case, the thermal conductivity of the second member made of ceramic is higher than the thermal conductivity of the first member made of glass, so heat is more likely to diffuse in the second member than in the first member, and the temperature of the second member is less likely to increase in the laser light irradiated region and its vicinity. However, even in such a case, according to the manufacturing method of a joined body according to

[12] , the glass layer can be melted while the second member made of ceramic is sufficiently heated.

[0019] A manufacturing method of a joined body according to one aspect of the present disclosure may be

[13] "the manufacturing method of a joined body according to any one of the above [1] to

[12] , in which the heat capacity of the second member is larger than the heat capacity of the first member." In this case, heat is more easily diffused in the second member than in the first member, and the temperature of the second member is less likely to increase in the laser light irradiated region and its vicinity. However, even in such a case, according to the manufacturing method of a joined body according to

[13] , the glass layer can be melted in a state in which the second member made of ceramic is sufficiently heated.

[0020] A manufacturing method of a joined body according to one aspect of the present disclosure may be

[14] "the manufacturing method of a joined body according to any one of the above [1] to

[13] , in which the thermal conductivity of the second member is higher than the thermal conductivity of the first member." In this case, heat is more easily diffused in the second member than in the first member, and the temperature of the second member is less likely to increase in the laser light irradiated region and its vicinity. However, even in such a case, according to the manufacturing method of a joined body according to

[14] , the glass layer can be melted in a state in which the second member made of ceramic is sufficiently heated.

[0021] A manufacturing method of a bonded body according to one aspect of the present disclosure may be

[15] "the manufacturing method of a bonded body according to any one of the above [1] to

[14] , in which, in the second step, the first member, the second member, and the glass layer are rotated in order to scan the laser light on different portions." According to the manufacturing method of a bonded body according to

[15] , it is possible to reliably perform scanning of the laser light on different portions while suppressing the complexity of the configuration on the side from which the laser light is emitted.

[0022] A manufacturing method of a bonded body according to one aspect of the present disclosure may be

[16] "the manufacturing method of a bonded body according to any one of the above [1] to

[15] , wherein in the second step, a package that houses a semiconductor element is formed by the first member and the second member that are bonded to each other via the glass layer." According to the manufacturing method of a bonded body according to

[16] , a package that houses a semiconductor element can be easily and reliably formed while suppressing thermal effects on the semiconductor element.

[0023] According to the present disclosure, it is possible to provide a method for manufacturing a joined body that can easily and reliably join a first member and a second member made of ceramics.

[0024] FIG. 1 is a longitudinal sectional view of a bonded body of one embodiment. FIG. 2 is a transverse sectional view of the bonded body taken along line II-II shown in FIG. 1. FIG. 3 is a configuration diagram of a laser processing apparatus for carrying out an example of a method for manufacturing the bonded body shown in FIG. 1. FIG. 4 is a longitudinal sectional view for explaining an example of a method for manufacturing the bonded body shown in FIG. 1. FIG. 5 is a longitudinal sectional view for explaining an example of a method for manufacturing the bonded body shown in FIG. 1. FIG. 6 is a longitudinal sectional view for explaining another example of a method for manufacturing the bonded body shown in FIG. 1. FIG. 7 is a longitudinal sectional view for explaining an example of a method for manufacturing a bonded body of another embodiment. FIG. 8 is a longitudinal sectional view for explaining another example of a method for manufacturing a bonded body of another embodiment.

[0025] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In each drawing, the same or corresponding parts are denoted by the same reference numerals, and duplicated explanations will be omitted. [Configuration of the joint body]

[0026] 1 and 2, the bonded body 1 includes a package 2 and a semiconductor element 3. The package 2 is composed of a first member 4, a second member 5, and a glass layer 6. The package 2 houses the semiconductor element 3, which is a light-emitting element or a light-receiving element.

[0027] The second member 5 is made of ceramics. The second member 5 has a bottomed cylindrical shape with its height direction aligned in the Z-axis direction. Specifically, the second member 5 has a bottom wall 51 and a side wall 52. The bottom wall 51 has a rectangular plate shape with its thickness direction aligned in the Z-axis direction. The side wall 52 has a rectangular cylindrical shape with its height direction aligned in the Z-axis direction. The side wall 52 includes a pair of side walls 53 and 54 facing each other in the X-axis direction and a pair of side walls 55 and 56 facing each other in the Y-axis direction. The side wall 52 defines an opening 5a facing the bottom wall 51 in the Z-axis direction. The semiconductor element 3 is disposed on the bottom surface 5b of the second member 5 (i.e., the surface of the bottom wall 51 facing the opening 5a).

[0028] The ceramic constituting the second member 5 is ceramic that is absorptive of the laser light L described below, or ceramic that contains an additive that is absorptive of the laser light L described below. The ceramic that is absorptive of the laser light L is, for example, aluminum nitride. The ceramic that contains an additive that is absorptive of the laser light L is, for example, aluminum oxide that contains, as an additive, a simple metal oxide such as iron oxide, copper oxide, or chromium oxide, or a mixture or composite of multiple types of metal oxides.

[0029] The first member 4 is made of glass. The first member 4 is shaped like a rectangular plate with its thickness direction in the Z-axis direction. The first member 4 is disposed on the side wall 52 and covers the opening 5a. The outer edge region of the surface 4a of the first member 4 faces the end face 52a of the side wall 52 in the Z-axis direction. If the semiconductor element 3 is a light-emitting element, light emitted from the semiconductor element 3 passes through the first member 4 and is emitted outside the package 2. If the semiconductor element 3 is a light-receiving element, light that passes through the first member 4 and enters the package 2 is incident on the semiconductor element 3.

[0030] The glass layer 6 is disposed between the first member 4 and the side wall 52. Specifically, the glass layer 6 is disposed between the outer edge region of the surface 4a of the first member 4 and the end face 52a of the side wall 52. When viewed from the Z-axis direction, which is the thickness direction of the glass layer 6, the glass layer 6 extends in the shape of a rectangular frame. The glass layer 6 bonds the first member 4 and the side wall 52, and hermetically seals the region between the first member 4 and the side wall 52. The material of the glass layer 6 is, for example, low-melting-point glass (vanadium phosphate glass, lead borate glass, etc.). [Method for manufacturing the bonded body]

[0031] An example of a manufacturing method of the bonded body 1 described above will be described. In this example of the manufacturing method of the bonded body 1, a laser processing apparatus 10 shown in FIG. 3 is used. As shown in FIG. 3, the laser processing apparatus 10 includes a mounting table 71 serving as a support 7, a light source 11, and a galvanometer mirror 12. The mounting table 71 supports an object (not shown). The light source 11 emits laser light L. The galvanometer mirror 12 reflects the laser light L emitted from the light source 11 toward the object on the mounting table 71 and scans the laser light L over the object on the mounting table 71. As shown by the solid line in FIG. 3, the galvanometer mirror 12 is disposed on one side of the mounting table 71 in a first direction D1 and on one side of the second direction D2 perpendicular to the first direction D1. As an example, the first direction D1 is a vertical direction, and the second direction D2 is a horizontal direction. Hereinafter, one side in the first direction D1 will be simply referred to as the "upper side," and one side in the second direction D2 will be simply referred to as the "right side."

[0032] 4A and 4B, the second member 5 having the semiconductor element 3 disposed on the bottom surface 5b, the first member 4 having the glass layer 6 fixed on the surface 4a, and the pressing portion 8 are placed in this order on the mounting table 71. As a result, the glass layer 6 is placed between the first member 4 and the second member 5 (first step). Specifically, with the first member 4 covering the opening 5a, the glass layer 6 is placed between the first member 4 and the side wall 52. The pressing portion 8 is a plate-shaped member made of glass and is transparent to the laser light L.

[0033] The fixing (pre-firing) of the glass layer 6 on the surface 4 a of the first member 4 is, for example, performed as follows. First, a powdered glass frit (glass powder) made of low-melting-point glass, an organic solvent such as amyl acetate, and a binder resin such as acrylic are kneaded together to prepare a frit paste containing these. Next, a paste layer is formed on the surface 4 a of the first member 4 by applying the frit paste. Next, the organic solvent is removed from the paste layer by drying, and further, the binder is gasified and the glass frit is melted by irradiation with laser light or heating in a furnace, thereby fixing the glass layer 6 on the surface 4 a of the first member 4.

[0034] After the first step, as shown in FIGS. 5A and 5B , the glass layer 6 is melted by irradiation with laser light L, thereby bonding the first member 4 and the second member 5 (step 2). The laser light L is irradiated by relatively moving the optical axis A of the laser light L along the glass layer 6 while the first member 4 is pressed against the second member 5 by the pressing unit 8 (i.e., by scanning the glass layer 6 with the laser light L by the galvanometer mirror 12). At this time, the laser light L passes through the pressing unit 8 and the first member 4 and is incident on the second member 5 and the glass layer 6. Bonding of the first member 4 and the second member 5 is achieved by a chemical reaction between the glass layer 6 and the ceramic second member 5 as the glass layer 6 melts and resolidifies. At this time, a portion of the first member 4 made of glass along the glass layer 6 may melt and resolidify. In the second step described above, the package 2 (see FIG. 1) that houses the semiconductor element 3 is formed by the first member 4 and the second member 5 that are joined together via the glass layer 6, and the joined body 1 is manufactured.

[0035] The second step described above will be described in more detail. It is assumed that the heat capacity of the second member 5 is greater than that of the first member 4, and that the thermal conductivity of the second member 5 is greater than that of the first member 4. The laser light L has a top-hat intensity distribution. That is, the laser light L has a region (e.g., a circular region or a rectangular region) where the intensity is uniform in a cross section of the laser light L perpendicular to the optical axis A or a cross section perpendicular to the first direction D1. The laser light L is scanned by oscillating the galvanometer mirror 12 (see FIG. 3 ) disposed above and to the right of the mounting table 71. The laser light L having a top-hat intensity distribution has a uniform intensity in a cross section perpendicular to the first direction D1 when, for example, an fθ lens is disposed downstream of the galvanometer mirror 12. The heat capacity of the first member 4 refers to the heat capacity of a portion joined to the second member 5 via the glass layer 6 and integrally formed from the same material. Similarly, the heat capacity of the second member 5 is the heat capacity of "a portion that is joined to the first member 4 via the glass layer 6 and is integrally formed from the same material." Furthermore, the thermal conductivity of the first member 4 is the thermal conductivity of "a portion that is joined to the second member 5 via the glass layer 6 and is integrally formed from the same material." Similarly, the thermal conductivity of the second member 5 is the thermal conductivity of "a portion that is joined to the first member 4 via the glass layer 6 and is integrally formed from the same material."

[0036] 5A, the second member 5 having the semiconductor element 3 disposed on its bottom surface 5b, the first member 4 having the glass layer 6 fixed on its front surface 4a, and the pressing unit 8 are placed on the mounting table 71 so that the Z-axis direction coincides with the first direction D1 and the X-axis direction coincides with the second direction D2. Then, the glass layer 6 on the end surface 52a of the sidewall 53 is irradiated with laser light L, and the glass layer 6 on the end surface 52a of the sidewall 54 is irradiated with laser light L. At this time, because the galvanometer mirror 12 (see FIG. 3) is disposed above and to the right of the mounting table 71, the scanning of the laser light L on the glass layer 6 extending in the Y-axis direction on the end surface 52a of each sidewall 53, 54 is performed along the Y-axis direction with the optical axis A of the laser light L tilted upward and to the right from the glass layer 6. In other words, the laser light L is irradiated so that the optical axis A of the laser light L is tilted with respect to the Z-axis direction, which is the thickness direction of the glass layer 6.

[0037] Next, the mounting table 71 is rotated 90 degrees about an axis parallel to the Z-axis direction as a center line, and the Y-axis direction is made to coincide with the second direction D2, as shown in Fig. 5B. Then, in a state in which the second member 5 having the semiconductor element 3 disposed on the bottom surface 5b, the first member 4 having the glass layer 6 fixed on the front surface 4a, and the pressing portion 8 are arranged on the mounting table 71 so that the Z-axis direction coincides with the first direction D1 and the Y-axis direction coincides with the second direction D2, the laser light L is irradiated onto the glass layer 6 on the end surface 52a of the side wall 55, and the laser light L is irradiated onto the glass layer 6 on the end surface 52a of the side wall 56. At this time, because the galvanometer mirror 12 (see FIG. 3) is disposed above and to the right of the mounting table 71, scanning of the laser light L on the glass layer 6 extending in the X-axis direction on the end faces 52a of each sidewall 55, 56 is performed along the X-axis direction with the optical axis A of the laser light L tilted above and to the right from the glass layer 6. In other words, irradiation of the laser light L is performed so that the optical axis A of the laser light L is tilted with respect to the Z-axis direction, which is the thickness direction of the glass layer 6. In this way, in the second step, the first member 4, the second member 5, and the glass layer 6 are rotated to scan different portions with the laser light L.

[0038] When the glass layer 6 on the end face 52 a of each side wall 53, 54, 55, 56 is irradiated with the laser light L, the laser light L is irradiated such that, in an irradiation region R of the second member 5 and the glass layer 6, the energy of the laser light L incident on the second member 5 without passing through the glass layer 6 is greater than the energy of the laser light L incident on the glass layer 6. Here, the "irradiation region R of the second member 5 and the glass layer 6 of the laser light L" refers to a region of the laser light L irradiated on the surface of the integrated body formed of the second member 5 and the glass layer 6, assuming that the second member 5 and the glass layer 6 do not completely transmit the laser light L. When the laser light L has a top-hat intensity distribution, the shape of the laser light L is defined by the outer edge of a region where the intensity is uniform in a cross section of the laser light L perpendicular to the optical axis A. When the laser light L has a Gaussian intensity distribution, the shape of the laser light L is defined by the outer edge of a region where the intensity is equal to or greater than half of the maximum value in a cross section of the laser light L perpendicular to the optical axis A. It should be noted that "the energy of the laser light L incident on the second member 5 without passing through the glass layer 6" does not include the energy of the laser light L that passes through the glass layer 6 and is incident on the second member 5. Also, "the energy of the laser light L incident on the glass layer 6" does not include the energy of the laser light L that passes through the second member 5 and is incident on the glass layer 6.

[0039] In this embodiment, the laser light L is irradiated so that the irradiation region R of the laser light L is located on each of the side walls 53, 54, 55, and 56 (i.e., on the second member 5) and on the glass layer 6. At this time, the laser light L is irradiated so that the energy of the laser light incident on the second member 5 without passing through the glass layer 6 in the irradiation region R of the laser light L is at least twice the energy of the laser light incident on the glass layer 6. Furthermore, the laser light L is irradiated so that the area of ​​the portion of the irradiation region R of the laser light L located on the second member 5 is larger than the area of ​​the portion of the irradiation region R of the laser light L located on the glass layer 6. [Action and Effect]

[0040] In the manufacturing method of the joined body 1, the laser light L is irradiated in the irradiation region R of the laser light L so that the energy of the laser light L incident on the second member 5 without passing through the glass layer 6 is greater than the energy of the laser light L incident on the glass layer 6. This allows the second member 5 made of ceramic to be sufficiently heated in and around the irradiation region R of the laser light L, thereby melting the glass layer 6. Therefore, according to the manufacturing method of the joined body 1, the first member 4 and the second member 5 made of ceramic can be easily and reliably joined.

[0041] If the laser light L is irradiated such that the energy of the laser light L incident on the glass layer 6 in the irradiation region R of the laser light L is greater than the energy of the laser light L incident on the second member 5 without passing through the glass layer 6, it would be difficult to reliably join the first member 4 and the second member 5 made of ceramics due to poor wettability of the glass layer 6 with respect to the second member 5 made of ceramics. In contrast, in the above-described method for manufacturing the joined body 1, the laser light L is irradiated such that the energy of the laser light L incident on the second member 5 without passing through the glass layer 6 is greater than the energy of the laser light L incident on the glass layer 6 in the irradiation region R of the laser light L. This allows the second member 5 made of ceramics to be preferentially heated in and near the irradiation region R of the laser light L, thereby raising the temperature of the second member 5. This promotes a chemical reaction at the interface between the second member 5 and the glass layer 6, thereby improving the joining speed and joining quality between the first member 4 and the second member 5 made of ceramics.

[0042] It is also conceivable to metallize each of the first member 4 and the second member 5 and join the first member 4 and the second member 5 via AuSn solder, but this requires a metallization process, which increases the number of steps, and also increases costs because the solder contains Au. Another conceivable method involves placing the first member 4 and the second member 5 with the glass layer 6 disposed between them in a furnace and heating them in the furnace to melt the glass layer 6. However, because the melting point of the glass layer 6 is much higher than that of the AuSn solder (at least about 360°C), heating in the furnace may damage the semiconductor element 3. The above-described method for manufacturing the joined body 1 solves these problems.

[0043] In the manufacturing method of the bonded body 1, the laser light L has a top-hat intensity distribution. As a result, even if the irradiation region R of the laser light L is slightly deviated from the desired position, it is possible to maintain a state in which the energy of the laser light L incident on the second member 5 without passing through the glass layer 6 is greater than the energy of the laser light L incident on the glass layer 6.

[0044] When the laser light L has a Gaussian intensity distribution, even if the irradiation region R of the laser light L is slightly displaced from the desired position, there is a risk that the energy of the laser light L incident on the glass layer 6 will become greater than the energy of the laser light L incident on the second member 5 without passing through the glass layer 6. Therefore, when the laser light L has a Gaussian intensity distribution, it is important to irradiate the laser light L so that the irradiation region R of the laser light L does not displace from the desired position.

[0045] In the manufacturing method of the bonded body 1, the ceramic constituting the second member 5 is either a ceramic that is absorptive of the laser light L or a ceramic that contains an additive that is absorptive of the laser light L. In either case, the second member 5 made of ceramic can be efficiently heated in and around the irradiation region R of the laser light L. Furthermore, when the semiconductor element 3 is a light-receiving element, detection of stray light caused by diffuse reflection within the package 2 can be suppressed.

[0046] In the method for manufacturing the joined body 1, the laser light L is irradiated such that the optical axis A of the laser light L is inclined with respect to the thickness direction of the glass layer 6. This makes it possible to easily and reliably position at least a portion of the irradiation region R of the laser light L on the second member 5. Even when the first member 4 is disposed on the end face 52 a of the side wall 52 with the glass layer 6 interposed therebetween, the laser light L is irradiated such that the optical axis A of the laser light L is inclined with respect to the thickness direction of the glass layer 6. This makes it possible to position a portion of the irradiation region R of the laser light L not only on the end face 52 a of the side wall 52 but also on the side surface of the side wall 52, thereby making it possible to melt the glass layer 6 while the second member 5 made of ceramic is sufficiently heated.

[0047] In the manufacturing method of the bonded body 1, scanning of the laser light L is performed by swinging the galvanometer mirror 12 that reflects the laser light L. This allows scanning of the laser light L according to the shape of the glass layer 6 to be performed at high speed.

[0048] In the method for manufacturing the joined body 1, the laser light L is irradiated so that the irradiation region R of the laser light L is located on the second member 5 and the glass layer 6. This allows the glass layer 6 to melt in a shorter time than when the irradiation region R of the laser light L is located on the second member 5 but not on the glass layer 6, thereby shortening the time required to join the first member 4 and the second member 5.

[0049] In the method for manufacturing the joined body 1, the laser light L is irradiated in the irradiation region R of the laser light L so that the energy of the laser light L incident on the second member 5 without passing through the glass layer 6 is at least twice the energy of the laser light L incident on the glass layer 6. This makes it possible to more easily and reliably join the first member 4 and the second member 5 made of ceramic.

[0050] In the method for manufacturing the bonded body 1, the laser light L is irradiated so that the area of ​​a portion of the irradiation region R of the laser light L that is located on the second member 5 is larger than the area of ​​a portion of the irradiation region R of the laser light L that is located on the glass layer 6. This makes it easier to create a state in which the energy of the laser light L that is incident on the second member 5 without passing through the glass layer 6 is larger than the energy of the laser light L that is incident on the glass layer 6. This effect is particularly noticeable when the laser light L has a top-hat intensity distribution.

[0051] In the manufacturing method of the joined body 1, the first member 4 is made of glass. In this case, the thermal conductivity of the second member 5 made of ceramic is higher than the thermal conductivity of the first member 4 made of glass. Therefore, heat is more easily diffused in the second member 5 than in the first member 4, and the temperature of the second member 5 is less likely to increase in the irradiated region R of the laser light L and its vicinity. However, even in such a case, the glass layer 6 can be melted with the second member 5 made of ceramic sufficiently heated.

[0052] In the manufacturing method of the joined body 1, the heat capacity of the second member 5 is larger than that of the first member 4. In this case, heat is more easily diffused in the second member 5 than in the first member 4, and the temperature of the second member 5 is less likely to increase in the irradiated region R of the laser light L and its vicinity. However, even in such a case, the glass layer 6 can be melted in a state where the second member 5 made of ceramic is sufficiently heated.

[0053] In the manufacturing method of the joined body 1, the thermal conductivity of the second member 5 is greater than that of the first member 4. In this case, heat is more easily diffused in the second member 5 than in the first member 4, and the temperature of the second member 5 is less likely to increase in the irradiated region R of the laser light L and its vicinity. However, even in such a case, the glass layer 6 can be melted in a state where the second member 5 made of ceramic is sufficiently heated.

[0054] In the manufacturing method of the bonded body 1, the first member 4, the second member 5, and the glass layer 6 are rotated in order to scan different portions with the laser light L. This makes it possible to reliably scan different portions with the laser light L while suppressing the complexity of the configuration on the side from which the laser light L is emitted.

[0055] In the manufacturing method of the bonded body 1, the package 2 that houses the semiconductor element 3 is formed by the first member 4 and the second member 5 that are bonded to each other via the glass layer 6. This makes it possible to easily and reliably form the package 2 that houses the semiconductor element 3 while suppressing thermal effects on the semiconductor element 3.

[0056] In particular, the package 2 that houses the semiconductor element 3 may require airtight sealing to ensure long-term reliability. Furthermore, if the semiconductor element 3 is a light-emitting element, the semiconductor element 3 itself generates heat, and therefore the package 2 that houses the semiconductor element 3 may require high heat dissipation properties. Under these circumstances, a manufacturing method for the bonded body 1 that can easily and reliably form the package 2 in which the second member 5 is made of ceramic is extremely effective.

[0057] In the manufacturing method of the bonded body 1, the glass layer 6 is fixed to the first member 4, and then the glass layer 6 is disposed between the first member 4 and the second member 5 (first step). Then, the glass layer 6 is melted by irradiating the first member 4 with laser light L, thereby bonding the first member 4 and the second member 5 (second step). Fixing the glass layer 6 to the first member 4 is effective when the material of the first member 4 is glass, which is a material that has better wettability with the first member 4 than with the second member 5, which is made of ceramic. Fixing the glass layer 6 to the first member 4 is also effective when the shape of the first member 4 is simpler than the shape of the second member 5, which is a plate-like shape. [Modification]

[0058] The present disclosure is not limited to the above embodiment. For example, as shown in FIG. 6A , the laser beam L may be irradiated such that the optical axis A of the laser beam L is inclined from the irradiation region R of the laser beam L toward the center of the second member 5 in all irradiation regions R. This allows for a more compact device for irradiating the laser beam L than when the device is configured such that the optical axis A of the laser beam L is inclined from the irradiation region R of the laser beam L toward the opposite side of the center of the second member 5. As an example, in the laser processing device 10 irradiating the laser beam L shown in FIG. 6A , the galvanometer mirror 12 is disposed above the center of the mounting table 71, as indicated by the two-dot chain line in FIG. 3 . Furthermore, the laser beam L may be irradiated such that the optical axis A of the laser beam L is parallel to the thickness direction of the glass layer 6, as shown in FIG. 6B . In this case, for example, by making the spot diameter of the laser beam L larger than the width of the glass layer 6, at least a portion of the irradiation region R of the laser beam L can be easily and reliably positioned on the second member 5.

[0059] The material of the first member 4 is not limited to glass. For example, the material of the first member 4 may be ceramic or metal. The shape of the first member 4 is not limited to a rectangular plate with the thickness direction in the Z-axis direction. The material of the second member 5 may be ceramic that does not absorb the laser light L, or ceramic that does not contain an additive that absorbs the laser light L. The shape of the second member 5 is not limited to a bottomed cylindrical shape with the height direction in the Z-axis direction. The heat capacity of the second member 5 may be smaller than that of the first member 4. The thermal conductivity of the second member 5 may be smaller than that of the first member 4. The shape of the glass layer 6 when viewed from the Z-axis direction, which is the thickness direction of the glass layer 6, is not limited to a rectangular frame shape. The glass layer 6 may be fixed to the second member 5 before the glass layer 6 is disposed between the first member 4 and the second member 5.

[0060] Other shapes of the first member 4 and the second member 5 will be described. As shown in FIGS. 7A and 7B , the first member 4 has a cap-like shape with its height direction aligned in the Z-axis direction. Specifically, the first member 4 has a top wall 41 and a side wall 42. The top wall 41 has a rectangular plate-like shape with its thickness direction aligned in the Z-axis direction. The side wall 42 has a rectangular cylindrical shape with its height direction aligned in the Z-axis direction. The side wall 42 includes a pair of side walls 43 and 44 facing each other in the X-axis direction and a pair of side walls 45 and 46 facing each other in the Y-axis direction. The side wall 42 defines an opening facing the top wall 41 in the Z-axis direction. The second member 5 has a rectangular plate-like shape with its thickness direction aligned in the Z-axis direction. The second member 5 covers the opening of the first member 4 with the outer edge region of the surface 5c of the second member 5 facing the end surface 42a of the side wall 42 in the Z-axis direction.

[0061] 7A and 7B, the semiconductor element 3 is disposed on the surface 5c of the second member 5. The glass layer 6 is disposed between the side wall 42 and the second member 5. Specifically, the glass layer 6 is disposed between the end surface 42a of the side wall 42 and the outer edge region of the surface 5c of the second member 5. When viewed from the Z-axis direction, which is the thickness direction of the glass layer 6, the glass layer 6 extends in the shape of a rectangular frame.

[0062] An example of a manufacturing method of the bonded body 1 in which the first member 4 has a cap-like shape and the second member 5 has a plate-like shape will be described. First, as shown in FIG. 7A , the second member 5 having the semiconductor element 3 disposed on the surface 5c, the first member 4 having the glass layer 6 fixed on the end face 42a, and the pressing unit 8 are placed on the mounting table 71 so that the Z-axis direction coincides with the first direction D1 and the X-axis direction coincides with the second direction D2. Then, the glass layer 6 on the end face 42a of the side wall 43 is irradiated with laser light L, and the glass layer 6 on the end face 42a of the side wall 44 is irradiated with laser light L. At this time, because the galvanometer mirror 12 (see FIG. 3 ) is disposed above and to the right of the mounting table 71, scanning of the laser light L with respect to the glass layer 6 extending in the Y-axis direction on the end faces 42a of each side wall 43, 44 is performed along the Y-axis direction with the optical axis A of the laser light L tilted upward and to the right from the glass layer 6. That is, the laser light L is irradiated so that the optical axis A of the laser light L is inclined with respect to the Z-axis direction, which is the thickness direction of the glass layer 6 .

[0063] Next, the mounting table 71 is rotated 90 degrees about an axis parallel to the Z-axis direction as a center line, so that the Y-axis direction is aligned with the second direction D2, as shown in Fig. 7B. Then, the second member 5 having the semiconductor element 3 disposed on the surface 5c, the first member 4 having the glass layer 6 fixed to the end face 42a, and the pressing portion 8 are arranged on the mounting table 71 so that the Z-axis direction is aligned with the first direction D1 and the Y-axis direction is aligned with the second direction D2. With this state in mind, the laser light L is irradiated onto the glass layer 6 on the end face 42a of the side wall 45, and the laser light L is irradiated onto the glass layer 6 on the end face 42a of the side wall 46. At this time, since the galvanometer mirror 12 (see FIG. 3) is disposed above and to the right of the mounting table 71, the scanning of the laser light L on the glass layer 6 extending in the X-axis direction on the end faces 42 a of each side wall 45, 46 is carried out along the X-axis direction with the optical axis A of the laser light L tilted above and to the right from the glass layer 6. In other words, the laser light L is irradiated so that the optical axis A of the laser light L is tilted with respect to the Z-axis direction, which is the thickness direction of the glass layer 6.

[0064] Even in an example of the manufacturing method of the joined body 1 in which the first member 4 has a cap-like shape and the second member 5 has a plate-like shape, when the laser light L is irradiated onto the glass layer 6 on the end face 42 a of each side wall 43, 44, 45, 46, the laser light L is irradiated such that, in the irradiation region R of the laser light L on the second member 5 and the glass layer 6, the energy of the laser light L incident on the second member 5 without passing through the glass layer 6 is greater than the energy of the laser light L incident on the glass layer 6.

[0065] 8A , the laser beam L may be irradiated such that the optical axis A of the laser beam L is inclined from the irradiation region R of the laser beam L toward the center of the second member 5 in all irradiation regions R. This allows the device for irradiating the laser beam L to be more compact than when the device is configured such that the optical axis A of the laser beam L is inclined from the irradiation region R of the laser beam L toward the opposite side of the center of the second member 5.

[0066] 8B , when the first member 4 is cap-shaped and the second member 5 is plate-shaped, the laser light L may be irradiated so that the optical axis A of the laser light L is parallel to the thickness direction of the glass layer 6. In this case, too, by making the spot diameter of the laser light L larger than the width of the glass layer 6, at least a portion of the irradiation region R of the laser light L can be easily and reliably positioned on the second member 5.

[0067] In any of the above-described embodiments and examples, the irradiation of the laser light L may be performed so that the irradiation region R of the laser light L is located on the second member 5 but not on the glass layer 6. This allows the glass layer 6 to be melted in a state where the second member 5 made of ceramic is more sufficiently heated, compared to the case where the irradiation region R of the laser light L is located on both the second member 5 and the glass layer 6, thereby improving the stability of the joining between the first member 4 and the second member 5.

[0068] In any of the above-described embodiments and examples, the laser light L does not have to have a top-hat intensity distribution. As long as the laser light L is irradiated in an irradiation region R of the second member 5 and the glass layer 6 with the laser light L such that the energy of the laser light L incident on the second member 5 without passing through the glass layer 6 is greater than the energy of the laser light L incident on the glass layer 6, the laser light L may have, for example, a Gaussian intensity distribution.

[0069] In any of the above-described forms and examples, the optical axis A of the laser light L may be moved relatively along the glass layer 6 by moving at least one of the “configuration on the side emitting the laser light L” and the mounting table 71.

[0070] The package 2 is not limited to one that houses a semiconductor element 3, which is a light-emitting element or a light-receiving element. The package 2 may also house other electronic components (e.g., a MEMS device, a quartz oscillator, a spatial light modulation device, etc.). The first member 4 and the second member 5 do not have to constitute a package for housing any component. The first member 4 and the second member 5 may each have a plate-like shape. Even when the first member 4 is not transparent to the laser light L and the second member 5 is plate-like, if the laser light L is irradiated so that the optical axis A of the laser light L is inclined with respect to the thickness direction of the glass layer 6, it becomes easier to position a portion of the irradiation region R of the laser light L on the second member 5 from the outside of the first member 4 and the second member 5. Therefore, the glass layer 6 can be melted while the second member 5 made of ceramic is sufficiently heated.

[0071] The glass layer 6 does not have to be formed in a continuous frame shape. Even when the first member 4 and the second member 5 form a package, the glass layer 6 does not have to be formed in a continuous frame shape, and the package does not have to be airtightly sealed. The frit paste used to fix the glass layer 6 may or may not contain a laser light absorbing material such as iron oxide.

[0072] 1...bonded body, 2...package, 3...semiconductor element, 4...first member, 5...second member, 6...glass layer, 12...galvanometer mirror, A...optical axis, L...laser light, R...irradiation area.

Claims

1. A method for manufacturing a joined body, comprising: a first step of arranging a glass layer between a first member and a second member made of ceramic; and a second step of joining the first member and the second member by irradiating the glass layer with laser light after the first step, wherein in the second step, the laser light is irradiated in an irradiated region of the second member and the glass layer such that the energy of the laser light incident on the second member without passing through the glass layer is greater than the energy of the laser light incident on the glass layer.

2. The method for manufacturing a bonded body according to claim 1, wherein the laser light has a top-hat intensity distribution.

3. The method for manufacturing a bonded body according to claim 1 or 2, wherein the ceramic is a ceramic that is absorptive of the laser light.

4. The method for manufacturing a bonded body according to claim 1 or 2, wherein the ceramic contains an additive that is absorptive of the laser beam.

5. A method for manufacturing a bonded body according to any one of claims 1 to 4, wherein in the second step, the irradiation of the laser light is carried out so that the optical axis of the laser light is inclined with respect to the thickness direction of the glass layer.

6. A method for manufacturing a bonded body as described in claim 5, wherein in the second step, the irradiation of the laser light is carried out so that the optical axis of the laser light is inclined from the irradiation area toward the center of the second member in all of the irradiation areas.

7. A method for manufacturing a bonded body according to any one of claims 1 to 6, wherein in the second step, scanning of the laser light is carried out by oscillating a galvanometer mirror that reflects the laser light.

8. A method for manufacturing a bonded body according to any one of claims 1 to 7, wherein in the second step, the irradiation of the laser light is carried out so that the irradiation area is located on the second member and on the glass layer.

9. A method for manufacturing a bonded body as described in claim 8, wherein in the second step, the irradiation of the laser light is carried out so that the energy of the laser light incident on the second member without passing through the glass layer in the irradiation area is at least twice the energy of the laser light incident on the glass layer.

10. A method for manufacturing a bonded body according to any one of claims 1 to 7, wherein in the second step, the irradiation of the laser light is carried out so that the irradiation area is located on the second member but not on the glass layer.

11. A method for manufacturing a bonded body according to any one of claims 1 to 10, wherein in the second step, the irradiation of the laser light is carried out so that the area of ​​the portion of the irradiation region located on the second member is larger than the area of ​​the portion of the irradiation region located on the glass layer.

12. A method for manufacturing a bonded body according to any one of claims 1 to 11, wherein the first member is made of glass.

13. A method for manufacturing a bonded body according to any one of claims 1 to 12, wherein the heat capacity of the second member is greater than the heat capacity of the first member.

14. A method for manufacturing a bonded body according to any one of claims 1 to 13, wherein the thermal conductivity of the second member is greater than the thermal conductivity of the first member.

15. A method for manufacturing a bonded body according to any one of claims 1 to 14, wherein in the second step, the first member, the second member, and the glass layer are rotated in order to scan the laser light over different portions.

16. A method for manufacturing a bonded body according to any one of claims 1 to 15, wherein in the second step, a package for accommodating a semiconductor element is formed by the first member and the second member bonded to each other via the glass layer.

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