JP5261151B2 - Package manufacturing method - Google Patents

Description

  The present invention relates to a method of manufacturing a package having a sealed space for protecting electronic components and the like that are sensitive to the surrounding environment.

  Conventionally, as a method of manufacturing a package for protecting electronic components sensitive to the surrounding environment such as a dye-sensitized solar cell element and an organic EL element, a frit is installed in a ring shape between two upper and lower glasses. A method of welding with a frit is known.

  For example, there are organic EL elements and dye-sensitized solar cell elements as electronic components. Since these are organic substances, they are vulnerable to heat and generally can only withstand temperatures of about 130 ° C. On the other hand, the melting point of the frit is about 400 ° C. even if it has a low melting point, and the method of heating the whole uniformly destroys the element, so that local heating is required. As this local heating method, there has been proposed a laser welding method in which only the frit portion is irradiated with a laser for a short time and the temperature is locally increased so that the element portion is sealed without being heated to a high temperature. .

  A conventional package manufacturing method will be described with reference to FIG. FIG. 4 is a plan view of an essential part of the package, and illustration of electronic components to be sealed is omitted.

  The upper glass 101 and the lower glass 102 are laminated via the frit 103 on the ring, and moved while irradiating a laser from the upper glass 101 so as to return from the a part to the a part through the b part, the c part, and the d part. By melting the frit, the upper glass 101 and the lower glass 102 are welded, and the frit 103 is solidified, whereby a package having a sealed space in a region surrounded by the frit 103 can be manufactured.

Here, since the laser is returned to point a and cracks frequently occur on the glass substrates 101 and 102 and the frit 103 immediately before the welding is completed, as countermeasures, the laser output is weakened, the focus is blurred, or the moving speed is slowed down. The method of doing was proposed.
JP 2008-527655 A

  However, in the conventional method, if the laser output is weakened in an attempt to avoid cracks, it takes time to raise the frit to its melting point, and during that time heat is transferred to the electronic component, causing the electronic component to be thermally damaged. There's a problem. Also, if the laser focus is defocused or the laser moving speed is slowed, cracking of the frit 103 and the glass substrates 101 and 102 can be prevented, but the temperature of the electronic component also rises, causing thermal damage to the electronic component. There is a problem that it ends up. That is, the method for preventing thermal damage of the electronic component and the method for preventing the frit 103 and the cracks of the glass substrates 101 and 102 are not satisfied at the same time. Thus, the conventional method has a problem in that it may not be applied depending on the electronic components housed inside.

  The present invention has been devised in view of the above circumstances, and an object of the present invention is to provide a highly reliable and highly versatile package manufacturing method that suppresses the occurrence of cracks.

  The method for manufacturing a package according to the present invention is (1) a method for manufacturing a package having a sealed space between two substrates arranged opposite to each other. A frit arranging step of arranging a frit so that a ring-shaped part forms a discontinuous pattern between the first end and the second end when viewed from the direction in which the substrates overlap, and so as to trace the frit A laser irradiation step of irradiating a laser to melt the frit and joining the two substrates; and combining the first end of the frit and the first so as to form a closed space together with the pattern of the frit A sealing step of disposing a sealing member between the two ends to form a sealed space between the two substrates.

  The package manufacturing method of the present invention is (2) the method of (1), wherein, in the sealing step, a glass member is used as the sealing member, and the molten glass member is the first part of the frit. It solidifies after pouring between one end and the second end.

  The package manufacturing method of the present invention is (3) in the above method (2), wherein the sealing step is performed after the frit at the first end or the second end is melted in the laser irradiation step. This is done during solidification.

  According to the package manufacturing method of (1) of the present invention, the closed space is formed by the frit and the sealing member, so that the two substrates are joined together, and the frit, the sealing member, and the two substrates are joined. A sealed space (hereinafter simply referred to as a sealed space) can be formed in a region surrounded by.

  Here, as a result of intensive investigations on the mechanism of crack generation in the conventional package manufacturing method, the occurrence of the crack is caused by the frit centered on the laser just before returning to the part a in FIG. The temperature distribution at 103 was found to be the cause. In other words, the frit 103 of the laser irradiation part is high temperature, and the periphery thereof has a temperature distribution on a concentric circle, which is lower than the irradiation part. The frit 103 expands in the laser irradiating portion having this high temperature, and the frit 103 tends to contract in the vicinity where the temperature becomes low. That is, a high tensile stress acts concentrically on the frit 103 around the laser irradiation portion. Here, at the rear of the laser irradiation part (rear with respect to the laser scanning direction), since the frit 103 is not yet completely solidified in the melted state, no crack is generated, but at the start point of the laser irradiation already welded. In a part a, the frit 103 was not completely deformed because the temperature was lowered and completely solidified, and it was found that cracks were generated due to tensile stress. In other words, in laser irradiation, it was found that the temperature distribution due to the laser was generated again in the frit once solidified, and tensile stress was generated, which occurred at the start and end points of laser irradiation. It has been found that such a phenomenon is peculiar when a local temperature distribution is generated by the laser.

  In response to the elucidation of the mechanism as described above, in the present invention, the frit pattern for joining two substrates by melting and solidifying by laser irradiation is interrupted at the first end and the second end. Even at the end point of the laser irradiation, the laser is not irradiated again to the frit which has already been bonded and solidified by two substrates. Therefore, even at the end point of the laser irradiation, the temperature distribution due to the laser irradiation does not occur again in the frit once solidified, and the accompanying tensile stress does not occur. And sealing space is formed by arrange | positioning a sealing member between a 1st end and a 2nd end by another process. For this reason, generation | occurrence | production of the frit and the crack in two base | substrates can be suppressed, and the manufacturing method of a reliable package can be provided.

  In addition, it is not necessary to provide more laser irradiation time and irradiation area, such as weakening the laser output, blurring the focus, and slowing the scanning speed as in the past. It is transmitted only to the central local part, and it is possible to suppress thermal damage to the electronic component to be accommodated therein. For this reason, since the package which suppressed generation | occurrence | production of a crack can be manufactured irrespective of the electronic component accommodated in, the manufacturing method of a highly versatile package can be provided.

  In addition, according to the package manufacturing method of (2) of the present invention, since the molten glass member only needs to be poured into the sealing step, a highly productive package manufacturing method can be provided.

  According to the package manufacturing method of (3) of the present invention, the bonding strength between the frit and the sealing member can be increased at the first end or the second end, and the heat generated by the molten sealing member is increased. Even if it is transmitted to the frit of the first end or the second end, stress due to temperature distribution can be relieved by deformation because it is not yet solidified, and therefore a more reliable package manufacturing method is provided. be able to.

  Hereinafter, the manufacturing method of the package of this invention is demonstrated in detail, referring drawings.

  1A is a top perspective view of a package manufactured by the method for manufacturing a package of the present invention, and FIG. 1B is a cross-sectional view taken along line II of FIG. In FIG. 1, 1 and 2 are a first substrate and a second substrate which are two substrates, 3 is a frit disposed between the two substrates 1 and 2, and 4 is a sealing member. Here, the frit 3 has a pattern in which part of the ring shape is interrupted at the first end 3a and the second end 3b, and the sealing member 4 is between the first end 3a and the second end 3b. The frit 3 and the sealing member 4 form a closed space. Electronic components such as a dye-sensitized solar cell element and an organic EL element are disposed in a sealing space between the frit 3, the sealing member 4, and the first and second substrates 1 and 2. However, illustration is abbreviate | omitted. In order to facilitate understanding, the frit 3 and the sealing member 4 are shaded. Moreover, although it is the same also about the following drawings, the same code | symbol is attached | subjected to the same location and the overlapping description is abbreviate | omitted.

  The package manufacturing method of the present invention is roughly divided into three steps. Hereinafter, each process is explained in full detail.

[Frit placement process]
A frit 3 is disposed between the substrates 1 and 2.

  The 1st base | substrate 1 will not be specifically limited if it has the intensity | strength which keeps sealing space, A ceramic substrate, a glass substrate, an organic resin substrate, etc. can be used.

  The second base 2 is not particularly limited as long as it has strength to maintain the sealed space and can transfer heat generated by laser irradiation to the frit 3 described later. For example, a glass substrate or the like can be used. The second substrate 2 may be the same material as the first substrate 1 or may be a different material, but it is preferable that the thermal expansion coefficients of both are close. In the figure, the second substrate 2 has the same shape as the first substrate 1, but may have a different shape as long as a sealing space can be formed therebetween.

  Moreover, what is necessary is just to select the 1st and 2nd base | substrates 1 and 2 according to the electronic component accommodated in an inside. For example, when a dye-sensitized solar cell element or an organic EL element is used as an electronic component, a light-transmitting material is selected, and the first or second substrate 1 or 2 is used as a substrate for forming the electronic component. In the case of use, one suitable for manufacturing electronic parts is selected.

  The frit 3 refers to a powdery glass raw material containing an additive in the glass technical field, but generally refers to a glass formed by melting a glass raw material outside the glass technical field. Let us show both. It is desirable that the frit 3 includes a light absorbing material in order to efficiently absorb the laser and melt or soften it. Moreover, it is desirable that it has a low melting point, and the composition may be adjusted to reduce the difference in thermal expansion between the first and second substrates 1 and 2. In particular, the material and composition of the frit 3 are not particularly limited as long as the first and second substrates 1 and 2 can be joined by being heated and melted by laser irradiation and then solidified. For example, a low melting point solder glass or the like can be used. Can be used.

  The frit 3 only needs to be arranged in a pattern in which a part of the ring shape is interrupted between the first base 1 and the second base 2, and even if it is arranged on the first base 1, it is arranged on the second base 2. May be. Moreover, although it is substantially rectangular shape in drawing, elliptical shape or polygonal shape may be sufficient.

  The first end 3a and the second end 3b of the frit 3 are arranged close to each other with an interval so that the temperature distribution generated by the laser when one of the frit 3 is irradiated with the laser does not melt the other frit 3. For example, the interval can be freely set. For example, the interval may be set to be about the same as the laser diameter described later or within three times.

  More specifically, it is desirable that the first end 3a and the second end 3b of the frit 3 are separated to a position where the temperature gradient generated by the laser when one of the frit 3 is irradiated with the laser does not affect the other. . The laser irradiation part is hot and the surroundings are cold, and tensile stress is generated in the low temperature part, but this stress is proportional to the temperature gradient. Therefore, the positional relationship between one end where the laser is irradiated and the other end where the laser is not irradiated is separated from the other end until the temperature gradient at the other end where the laser is not irradiated is small. It is desirable to avoid this. The temperature gradient generated by the laser varies depending on the laser output, the laser irradiation area, the thickness and material of the first and second substrates 1 and 2, the surface condition, the atmosphere condition, etc., and the relationship between the distance and the temperature gradient is generally determined. Although it cannot be specified, the temperature gradient due to the laser generally becomes strong in the vicinity of the laser irradiation portion, and becomes smaller after a certain distance. Therefore, it is desirable to provide the first end 3a and the second end 3b at a distance of about 10 times the laser irradiation diameter, generally the same as the laser irradiation diameter.

  The width of the frit 3 is preferably 0.3 mm to 3.0 mm. When the width of the frit 3 is 0.3 mm or more, a sufficient adhesion area can be ensured. Therefore, the sealing failure due to incomplete sealing due to the generation of discontinuous portions or gaps in the frit 3. Occurrence can be suppressed. In addition, since it is securely connected to the bases 1 and 2 with sufficient adhesive force, a highly reliable package can be provided. Since the width of the frit 3 is 3.0 mm or less, a large amount of heat is not required for melting, which is preferable. In particular, even when an electronic component that is sensitive to heat is accommodated in the sealed space, the peripheral portion of the frit 3 does not reach a high temperature, so that it is possible to suppress the transfer of heat to the electronic component when the frit 3 melts. . Therefore, the width of the frit 3 is desirably in the range of 0.3 mm to 3.0 mm. The height of the frit 3 is preferably between 3 μm and 500 μm. If the height of the frit 3 is 3 μm or more, the bases 1 and 2 can be held at an interval, and a sealed space can be stably formed by suppressing generation of gaps and discontinuous portions in the frit 3. Can be held. On the other hand, if the height is 500 μm or less, heat by laser irradiation can be easily transmitted in the thickness direction, and the amount of heat necessary for melting can be suppressed. As a result, even when an electronic component that is sensitive to heat is accommodated in the sealed space, the peripheral portion of the frit 3 does not become high temperature, and heat from the laser irradiation can be suppressed from being transmitted to the electronic component. Regardless of this, it is possible to provide a highly versatile package manufacturing method that can be applied. Therefore, the height of the frit 3 is preferably between 3 μm and 500 μm.

[Laser irradiation process]
In this state, the first base 1 and the second base 2 are stacked via the frit 3, and the laser is scanned so that the laser is irradiated to the frit 3 via the second base 2. The frit 3 is melted by laser irradiation and then solidified to join the first base 1 and the second base 2 together.

  Here, the diameter of the laser to be irradiated is 1.01D1 <D2 when the width of the frit 3 is D1 and the diameter of the laser is D2 in order to sufficiently generate heat and melt the entire width of the frit 3. A range of <3.0D1 is desirable. If D2 is larger than 1.01D1, the laser can be applied to the entire width of the frit 3 even if a laser beam misalignment or a dimensional error of the frit 3 occurs, resulting in partial unwelding. The occurrence of poor sealing can be suppressed. Further, if D2 is smaller than 3.0D1, the irradiated energy can be used efficiently, and the laser irradiation surface leaking to the outside of the frit 3 can be kept small. And the occurrence of thermal instability can be suppressed. Therefore, the laser diameter D2 is preferably in the range of 1.01D1 <D2 <3.0D1.

  The laser scanning method may be performed by a single laser or a plurality of lasers, but the trajectories of the individual lasers do not overlap so that the frit once melted and solidified by laser irradiation is not irradiated again. Set as follows. For example, in the case of using a single laser, the pattern of the frit 3 may be traced from the first end 3a to the second end 3b. In the case of using two lasers, for example, the pattern of the frit 3 may be divided into two sections and scanned so as to be separated from the division point A to the first end 3a and the second end 3b.

  By scanning the laser in this manner, the frit 3 once solidified does not exist in the range where heat is transferred at the end point of laser irradiation, so that the generation of cracks in the frit 3 and the substrates 1 and 2 due to laser irradiation is suppressed. be able to.

[Sealing process]
Next, the sealing member 4 is disposed in the unwelded portion between the first end 3 a and the second end 3 b of the frit 3 to form a sealing space surrounded by the bases 1, 2, the frit 3, and the sealing member 4. Form.

  The shape of the sealing member 4 is not particularly limited as long as the sealing member 4 is arranged so as to form a closed space together with the pattern of the frit 3. As shown in FIG. 1A, it may be arranged between the first end 3a and the second end 3b of the frit 3 with a width equal to the width of the frit 3, or as shown in FIG. It may be thicker than the width of the frit 3. Further, if the closed space can be realized, the width of the frit 3 may be narrower. Further, as shown in FIG. 2 (b), the frit 3 may be configured to cover the first end 3a and the second end 3b, or as shown in FIG. You may block | close between the 1st end 3a and the 2nd end 3b from the outer side of a pattern.

  The arrangement method of the sealing member 4 is not limited as long as the sealing space can be sealed together with the frit 3. For example, the following method may be used.

First Method After the laser irradiation step, the sealing member 4 made of a molten glass member is poured and solidified so as to connect a minute gap between the first end 3a and the second end 3b.

  The method for supplying the molten sealing member 4 is, for example, for forming a preliminary pattern 4 ′ of the sealing member 4 in the frit arranging step, and subsequently configuring the sealing member 4 after the laser irradiation step. The preliminary pattern 4 ′ may be melted by irradiating a laser. The preliminary pattern 4 ′ of the sealing member 4 may be a pattern integrated with the pattern of the frit 3 or a separated pattern. For example, as shown in FIG. 3 (a), a dot-like pattern may be provided between the first end 3a and the second end 3b of the frit 3 with a gap therebetween, or in FIG. 3 (b). As shown in FIG. 3, the first end 3a or the second end 3b of the frit 3 may be provided continuously, or as shown in FIG. You may arrange | position so that it may respond | correspond to the space | interval of the end 3a and the 2nd end 3b.

  As the propulsive force for pouring the molten sealing member 4 supplied in this way, gravity generated by tilting the substrates 1 and 2 may be used, or an external force using warm air or a probe is used. Also good. For example, in the case of using gravity, in FIG. 3 (a), the left and right sides may be inclined in order, and in FIG. 3 (b), the left side is down, FIG. 3 (c). Then, it is sufficient to tilt each so that the upper side is down.

  Here, the sealing member 4 is preferably arranged in a state where the frit 3 at the first end 3a or the second end 3c is melted by the laser irradiation process. By doing in this way, since the melted frit 3 and the sealing member 4 are firmly joined and can be connected without a gap at the connecting portion between them, a stable sealing space can be realized. Further, even if heat from the melted sealing member 4 is transmitted to the first end 3a or the second end 3c of the frit 3, the frit 3 is melted so that the stress caused by the sealing member 4 is relieved by deformation. Therefore, a more reliable manufacturing method can be provided. The heat transfer by the sealing member 4 is small in the first place because the necessary amount is extremely small, and is extremely small compared to the heat transfer by laser irradiation, so the first end 3a or the second end 3c. Even if the frit 3 is solidified, it does not become a big problem as in the prior art.

  As shown in FIG. 3B, when the preliminary pattern 4 ′ of the sealing member 4 is continuously arranged and integrated with the pattern of the frit 3, the preliminary pattern 4 ′ is irradiated with laser. Is also transmitted to the frit 3 (second end 3b in the figure) that is continuous with the preliminary pattern 4 ', and therefore, the portion (second end 3b in the figure) that is continuous with the preliminary pattern 4'. ) Is preferably melted.

Second Method The sealing member 4 is supplied from the outside and disposed between the first end 3 a and the second end 3 b of the frit 3. For example, the sealing member 4 may be disposed by solidifying the molten glass member after pouring, or the sealing member 4 made of an organic resin may be poured and disposed.

  Although the material of the sealing member 4 arranged in this way is somewhat restricted depending on the arrangement method, the material is basically not limited as long as the sealing space can be sealed together with the frit 3. For example, when the first method is adopted as the arrangement method of the sealing member 4, the same material as the frit 3 can be used. When the second method is adopted, an organic resin material or the like can be used, but a material having a thermal expansion coefficient close to that of the substrates 1 and 2 is preferably used.

  By passing through the above three steps, a package having a sealed space surrounded by the bases 1, 2, frit 3, and sealing member 4 can be provided.

  In this way, the sealing space is formed in two stages, that is, the joining of the bases 1 and 2 by the frit 3 and the joining of the bases 1 and 2 by the sealing member 4. Since the sealing space can be formed while suppressing the generation of cracks in the frit 3 and the bases 1 and 2 resulting from remelting, it is possible to provide a highly reliable package manufacturing method.

  In particular, it is necessary to make the laser irradiation time and irradiation area longer than necessary, or to widen the range, such as weakening the laser output, blurring the focus, slowing the scanning speed as in the past. Therefore, the package can be manufactured with the minimum necessary laser irradiation. In other words, heat from the laser is transmitted only to a local portion centered on the frit 3, and it is possible to prevent the electronic component to be accommodated therein from being damaged by heat. For this reason, even when an electronic component using an organic substance that is weak against heat, for example, an organic EL element or a dye-sensitized embryonic battery element is accommodated in the sealed space, the heat of laser irradiation is applied to the electronic component. The package can be manufactured without transmission. That is, even for an electronic component having low heat resistance, the package can be manufactured without causing the electronic component to be damaged by heat, which is suitable for sealing such an electronic component. As described above, it is possible to provide a highly versatile package manufacturing method that suppresses the generation of cracks regardless of the electronic components housed inside.

  In the manufacturing method of the package of the present invention, it is important to prevent remelting of the already solidified frit 3 by setting the end point of the laser trajectory to a portion where the frit is interrupted. The start and end points of the laser trajectory and the arrangement method of the sealing member 4 can be freely set.

  For example, in FIG. 1A, the division points A that divide the frit 3 pattern into two sections are made equal in length, but may be different.

  Furthermore, in FIGS. 1 to 3, the portion where the frit 3 is interrupted (between the first end 3 a and the second end 3 b) is provided at the corner of the planar shape of the sealing space. Good. In the case where the start point and end point of each laser are provided in the straight line portion of the frit 3, the thermal stress generated at the start point and end point is affected by the stress concentration due to the shape factor of the corner of the frit 3. Can be avoided, and sealing can be performed more stably.

  In FIG. 1, the first substrate 1 and the second substrate 2 are described as examples of flat substrates, but one of them may be a cap. In this case, the substrate-like base is placed opposite to each other so as to cover the cap-like base, and the frit 3 and the sealing member 4 are disposed on the upper surface of the cap-like base. That's fine.

  Two glass substrates having outer dimensions of 60 × 60 × 1.1 mm in thickness are used as first and second bases 1 and 2 through a frit 3 having a pattern in which a ring-shaped part is broken as shown in FIG. The glass frit 3 was laminated and welded with a laser to produce a package. The frit 3 was formed in a ring shape with a width of 1 mm in a 30 × 30 mm region between the upper and lower glasses. The interval between the interrupted portions (the first end 3a and the second end 3b) was 1 mm. Under this basic condition, laser irradiation is performed so that the pattern of the frit 3 is traced from the first end 3a to the second end 3b, and then the sealing member 4 made of a molten glass member is connected to the first end 3a and the second end. 100 packages were manufactured by pouring between the ends 3b. As a result, no cracks occurred in all 100 packages.

  For comparison, 100 packages were manufactured by the same manufacturing method as before. In addition, the pattern of the frit 3 was made into the ring shape without a broken part. As a result, cracks were observed in all 100 packages.

(A), (b) is the top view and sectional drawing which show the package sealed by the frit, respectively. (A)-(c) is a top view which shows the example of arrangement | positioning of the sealing member in the manufacturing method of the package of this invention, respectively. (A)-(c) is a top view which shows the example of arrangement | positioning of the preliminary pattern of the sealing member in the manufacturing method of the package of this invention, respectively. It is a top view which shows the manufacturing method of the conventional package.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st base | substrate 2 2nd base | substrate 3 Frit 3a 1st end 3b 2nd end 4 Sealing member

Claims (4)

A method of manufacturing a package having a sealed space between two substrates disposed opposite to each other,
A frit arranged between the two bases so that a ring-shaped part of the first base and the second end forms a discontinuous pattern when viewed from the direction in which the two bases overlap. The placement process;
A laser irradiation step of irradiating a laser so as to trace the frit, melting the frit and joining the two substrates;
A sealing member is disposed between the first end and the second end of the frit so as to form a closed space together with the pattern of the frit, and sealed between the two substrates. Forming a sealed space, and
In the frit arranging step, said second end and said first end, a laser on the diameter or irradiating in the laser irradiation step, a package for arranging the frit to be close spaced three times or less Production method. The package manufacturing method according to claim 1, wherein in the sealing step, the same material as the frit is used as the sealing member. A method of manufacturing a package having a sealed space between two substrates disposed opposite to each other,
A frit arranged between the two bases so that a ring-shaped part of the first base and the second end forms a discontinuous pattern when viewed from the direction in which the two bases overlap. The placement process;
A laser irradiation step of irradiating a laser so as to trace the frit, melting the frit and joining the two substrates;
A sealing member is disposed between the first end and the second end of the frit so as to form a closed space together with the pattern of the frit, and sealed between the two substrates. Forming a sealed space, and
In the sealing step, a method for manufacturing a package, wherein a glass member is used as the sealing member, and the molten glass member is poured between the first end and the second end of the frit and then solidified. The package manufacturing method according to claim 3, wherein the sealing step is performed while the frit at the first end or the second end is melted and solidified in the laser irradiation step.