Method for manufacturing joined body

Abstract

To provide a method for manufacturing a joined body, capable of easily and reliably joining a first member and a ceramic second member.SOLUTION: A method for manufacturing a joined body 1 includes: a first step in which a glass layer 6 is disposed between a first member 4 and a ceramic second member 5; and a second step in which, after the first step, the first member 4 and the second member 5 are joined by melting the glass layer 6 by irradiation with laser light L. In the second step, the irradiation with the laser light L is performed in an irradiation region R, with the laser light L, of the second member 5 and the glass layer 6 such that the energy of the laser light L incident on the second member 5 without passing through the glass layer 6 is made to be greater than the energy of the laser light L incident on the glass layer 6.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a method for producing a bonded body. [Background technology]

[0002] A method for manufacturing a bonded 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 bonding the first member and the second member (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-161013 Summary of the Invention [Problem to be solved by the invention]

[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 bond between the first member and the second member made of ceramic may become unstable.

[0005] Therefore, an object of the present invention is to provide a method for manufacturing a bonded body that can easily and reliably bond a first member and a second member made of ceramics. [Means for solving the problem]

[0006] The method for manufacturing a joined body of the present invention is [1] "a method for manufacturing a joined body comprising: a first step of placing 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 melting the glass layer by irradiating laser light, wherein in the second step, the irradiation of the laser light is carried out so 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, laser light is irradiated in the laser light irradiated region of the second member and the glass layer so 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. This allows the glass layer to melt in a state where the second member made of ceramic is sufficiently heated in and around the laser light irradiated region. Therefore, the method for manufacturing a joined body described in [1] above can easily and reliably join the first member and the second member made of ceramic.

[0008] The method for manufacturing a bonded body of the present invention may be [2] "the method for manufacturing a bonded body according to the above [1], wherein the laser beam has a top-hat intensity distribution." According to the method for manufacturing a bonded body according to [2], even if the irradiation region of the laser beam is slightly shifted from a desired position, it is possible to maintain a state in which 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.

[0009] The method for manufacturing a joined body of the present invention may be [3] "the method for manufacturing a joined body according to the above [1] or [2], wherein the ceramic is a ceramic that is absorptive to the laser beam." According to the method for manufacturing a 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] The method for manufacturing a joined body of the present invention may be [4] "the method for manufacturing a joined body according to the above [1] or [2], wherein the ceramic is a ceramic containing an additive that is absorptive of the laser beam." According to the method for manufacturing 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] The method for manufacturing a bonded body of the present invention may be [5] "the method for manufacturing 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 carried out so that the optical axis of the laser light is inclined with respect to the thickness direction of the glass layer." According to the method for manufacturing 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] The method for manufacturing a bonded body of the present invention may be [6] "the method for manufacturing 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 tilted from the irradiation region toward the center of the second member in all the irradiation regions." According to the method for manufacturing a bonded body according to [6], it is possible to reduce the size of an apparatus for irradiating laser light, compared to when the apparatus is configured so that the optical axis of the laser light is tilted from the irradiation region toward the opposite side from the center of the second member.

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

[0014] The method for manufacturing a bonded body of the present invention may be [8] "the method for manufacturing 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 carried out so that the irradiation region is located on the second member and on the glass layer." According to the method for manufacturing 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] The method for manufacturing a joined body of the present invention may be [9] "the method for manufacturing a joined body according to the above [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 is at least twice the energy of the laser light incident on the glass layer in the irradiation region." According to the method for manufacturing a joined body according to

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

[0016] The method for manufacturing a joined body of the present invention may be

[10] "the method for manufacturing 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 carried out so that the irradiated region is located on the second member and not on the glass layer." According to the method for manufacturing 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 when 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] The method for manufacturing a bonded body of the present invention may be

[11] "a method for manufacturing 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 carried out so that the area of ​​a portion of the irradiation region located on the second member is larger than the area of ​​a portion of the irradiation region located on the glass layer." According to the method for manufacturing a bonded body according to

[11] , it is possible to more easily create 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] The method for manufacturing a joined body of the present invention may be

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

[11] , wherein the first member is made of glass." In this case, the thermal conductivity of the second member made of ceramic is higher than that of the first member made of glass, so heat diffuses more easily 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 method for manufacturing a joined body according to

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

[0019] The method for manufacturing a joined body of the present invention may be

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

[12] , wherein the heat capacity of the second member is larger than that 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 method for manufacturing a joined body according to

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

[0020] The method for manufacturing a joined body of the present invention may be

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

[13] , wherein the thermal conductivity of the second member is higher than that 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 method for manufacturing a joined body according to

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

[0021] The manufacturing method of the bonded body of the present invention may be

[15] "the manufacturing method of the bonded body according to any one of the above [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 on different portions." According to the manufacturing method of the 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] The method for manufacturing a bonded body of the present invention may be

[16] "the method for manufacturing 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 method for manufacturing 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. [Effects of the Invention]

[0023] According to the present invention, it is possible to provide a method for manufacturing a bonded body that can easily and reliably bond a first member and a second member made of ceramics. [Brief explanation of the drawings]

[0024] [Figure 1] FIG. 2 is a longitudinal sectional view of the bonded body according to the embodiment. [Figure 2]FIG. 2 is a cross-sectional view of the bonded body taken along line II-II shown in FIG. [Figure 3] 2 is a configuration diagram of a laser processing device for carrying out an example of a method for manufacturing the bonded body shown in FIG. 1. FIG. [Figure 4] 2 is a vertical cross-sectional view illustrating an example of a method for manufacturing the bonded body shown in FIG. 1. FIG. [Figure 5] 2 is a vertical cross-sectional view illustrating an example of a method for manufacturing the bonded body shown in FIG. 1. FIG. [Figure 6] 1. FIG. 4 is a vertical cross-sectional view illustrating another example of a method for manufacturing the bonded body shown in FIG. [Figure 7] FIG. 10 is a vertical cross-sectional view illustrating an example of a method for manufacturing a bonded body according to another embodiment. [Figure 8] FIG. 10 is a vertical cross-sectional view illustrating another example of the method for manufacturing a bonded body according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0025] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each drawing, the same or corresponding parts are designated by the same reference numerals, and redundant explanations will be omitted. [Construction of the zygote]

[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 cylindrical shape with a bottom and a height direction along the Z-axis. 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 a thickness direction along the Z-axis. The side wall 52 has a rectangular cylindrical shape with a height direction along the Z-axis. 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 a bottom surface 5b of the second member 5 (i.e., the surface of the bottom wall 51 on the opening 5a side).

[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. An example of the ceramic that is absorptive of the laser light L is aluminum nitride. An example of the ceramic that contains an additive that is absorptive of the laser light L is 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 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 to the outside of 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 together, 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 of manufacturing the bonded body]

[0031] An example of a manufacturing method of the bonded body 1 described above will be described. In the 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 object on the mounting table 71 with the laser light L. 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] 4(a) and 4(b), 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 4a of the first component 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 4a of the first component 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 4a of the first component 4.

[0034] After the first step, as shown in FIGS. 5(a) and 5(b), the glass layer 6 is melted by irradiation with laser light L, thereby bonding the first member 4 and the second member 5 (second step). 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. The bonding between the first member 4 and the second member 5 is achieved by a chemical reaction between the glass layer 6 and the second member 5 made of ceramic when 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 second member 5 has a larger heat capacity than the first member 4, and that the thermal conductivity of the second member 5 is larger 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 bonded to the second member 5 via the glass layer 6 and integrally formed of the same material. Similarly, the heat capacity of the second member 5 is the heat capacity of "the 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 "the 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 "the 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 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 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 around an axis parallel to the Z-axis direction as a center line, and the Y-axis direction is aligned with the second direction D2, as shown in Fig. 5(b). 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 unit 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, the glass layer 6 on the end surface 52a of the side wall 55 is irradiated with laser light L, and the glass layer 6 on the end surface 52a of the side wall 56 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 laser light L scans the glass layer 6 extending in the X-axis direction on the end surfaces 52a of the side walls 55, 56 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. 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 the region of the laser light L irradiated on the surface of the integrated object formed by 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, 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 that is located on the second member 5 is larger than the area of ​​the portion of the irradiation region R of the laser light L that is 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 makes it possible to melt the glass layer 6 in a state where the second member 5 made of ceramic is sufficiently heated in and around the irradiation region R of the laser light L. 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 in the irradiation region R of the laser light L so that the energy of the laser light L incident on the glass layer 6 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 manufacturing method of the joined body 1 described above, 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. Therefore, the second member 5 made of ceramics can be preferentially heated in and around 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 then join the first member 4 and the second member 5 via AuSn solder, but this requires a metallization step, which increases the number of steps, and also increases costs because the solder contains Au. Another conceivable method is to place the first member 4 and the second member 5, with the glass layer 6 disposed between them, in a furnace and heat 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 AuSn solder (the lowest being 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 shifted 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, the energy of the laser light L incident on the glass layer 6 may 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 a ceramic that is absorptive to the laser light L, or a ceramic that contains an additive that is absorptive to 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 52a 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 52a of the side wall 52 but also on the side surface of the side wall 52, thereby melting the glass layer 6 while the second member 5 made of ceramic is sufficiently heated.

[0047] In the method for manufacturing the bonded body 1, scanning with the laser light L is performed by oscillating the galvanometer mirror 12 that reflects the laser light L. This allows scanning with 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 bonded 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 bond the first member 4 and the second member 5.

[0049] In the method for manufacturing the bonded 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 bond the first member 4 and the second member 5 made of ceramics.

[0050] In the method for manufacturing the bonded body 1, the laser light L is irradiated so that the area of ​​the 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 ​​the 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 that of the first member 4 made of glass. Therefore, heat diffuses more easily 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 bonded 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 with the second member 5 made of ceramics 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 with the second member 5 made of ceramics 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 irradiation with laser light L, thereby bonding the first member 4 and the second member 5 (second step). When the material of the first member 4 is glass, for example, and the first member 4 is made of a material that has better wettability with the glass layer 6 than with the second member 5 made of ceramic, it is effective to fix the glass layer 6 to the first member 4. When the shape of the first member 4 is simpler than the shape of the second member 5, for example, when the shape of the first member 4 is plate-like, it is effective to fix the glass layer 6 to the first member 4. [Variations]

[0058] The present invention 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 is cap-shaped 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 is rectangular plate-shaped with its thickness direction aligned in the Z-axis direction. The side wall 42 is rectangular tubular 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 is rectangular plate-shaped 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 face 42a of the side wall 42 in the Z-axis direction.

[0061] 7(a) and 7(b), 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 method for manufacturing the bonded body 1 in a case where 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 a 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. In this state, 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, since 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 around an axis parallel to the Z-axis direction as a center line, and the Y-axis direction is aligned with the second direction D2, as shown in Fig. 7(b). Then, in a state in which the second member 5 having the semiconductor element 3 arranged on the surface 5c, the first member 4 having the glass layer 6 fixed to the end face 42a, and the pressing unit 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, the glass layer 6 on the end face 42a of the side wall 45 is irradiated with laser light L, and the glass layer 6 on the end face 42a of the side wall 46 is irradiated with laser light L. 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 42a of the side walls 45, 46 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, 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 bonded 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 42a of each side wall 43, 44, 45, 46, the laser light L is irradiated so 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] 8(a), the laser beam L may be irradiated so 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 so 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] 8(b), the laser beam L may be irradiated so that the optical axis A of the laser beam L is parallel to the thickness direction of the glass layer 6. In this case, too, 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.

[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 melt in a state where the second member 5 made of ceramic is more sufficiently heated, compared to when 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. In the irradiation region R of the second member 5 and the glass layer 6 with the laser light L, the laser light L may have, for example, a Gaussian intensity distribution as long as the laser light L is irradiated 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.

[0069] In any of the above-described embodiments 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 that 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 part 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, and therefore the glass layer 6 can be melted in a state where 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. [Explanation of symbols]

[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 first step of disposing a glass layer between a first member and a second member made of ceramic; a second step of joining the first member and the second member by melting the glass layer by irradiating it with laser light after the first step, In the second step, the laser light is irradiated onto the second member and the glass layer in an irradiation region of the laser light so 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 , 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 , wherein the ceramic contains an additive that is absorptive of the laser beam.

5. The method for manufacturing a bonded body according to claim 1 , wherein in the second step, the laser light is irradiated so that an optical axis of the laser light is inclined with respect to a thickness direction of the glass layer.

6. 6. The method for manufacturing a joined body according to claim 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.

7. The method for manufacturing a bonded body according to claim 1 , wherein in the second step, the laser beam is scanned by oscillating a galvanometer mirror that reflects the laser beam.

8. The method for manufacturing a bonded body according to claim 1 , wherein in the second step, the laser light is irradiated so that the irradiated region is located on the second member and the glass layer.

9. 9. The method for manufacturing a joined body according to claim 8, wherein in the second step, the irradiation of the laser light is performed such that, in the irradiation region, 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.

10. The method for manufacturing a bonded body according to claim 1 , 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 not on the glass layer.

11. 2. The method for manufacturing a joined body according to claim 1, wherein in the second step, the irradiation of the laser light is performed so 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.

12. The method for manufacturing a bonded body according to claim 1 , wherein the first member is made of glass.

13. The method for manufacturing a bonded body according to claim 1 , wherein the second member has a larger heat capacity than the first member.

14. The method for manufacturing a bonded body according to claim 1 , wherein the thermal conductivity of the second member is greater than the thermal conductivity of the first member.

15. The method for manufacturing a bonded body according to claim 1 , wherein in the second step, the first member, the second member, and the glass layer are rotated to scan the laser light over different portions.

16. The method for manufacturing a bonded body according to claim 1 , 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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