JP6867263B2 - Bonded structure and semiconductor package - Google Patents

Description

The present invention relates to a bonding structure and a semiconductor package including a bonding material interposed between a lead terminal and a line conductor.

As a semiconductor package on which a semiconductor element such as an optical semiconductor element is mounted, a package including a substrate on which the semiconductor element is mounted and a lead terminal fixed to the substrate is known. The mounting of the semiconductor element on the substrate and the fixing of the lead terminal are performed, for example, via an insulating member such as a dielectric substrate.

In this case, in the semiconductor package, the signal terminals are joined and fixed to the dielectric substrate via a brazing material such as gold-tin or tin-silver. The signal terminal is a metal lead pin terminal or the like. A metal layer is provided in advance on the surface of the dielectric substrate to which the brazing material is bonded (see, for example, Patent Document 1).

International Publication No. 2017/033860 Japanese Unexamined Patent Publication No. 9-330949

In a semiconductor package, it is required to improve the reliability of electrical and mechanical connection between a signal terminal and a substrate. Further, a joining structure effective for improving such connection reliability is required.

The bonding structure of one embodiment of the present invention includes a metal terminal having an end portion, a line conductor in which the end portion of the metal terminal is located, and metal particles, and the end portion of the metal terminal. It is provided with a bonding material interposed between the line conductor. Further, a gap is located along the bonding interface between the end portion of the metal terminal and the bonding material.

The semiconductor package according to one aspect of the present invention includes a substrate having a first surface and a second surface opposite to the first surface, a line conductor located on the first surface side of the substrate, and the first surface of the substrate. It penetrates from two surfaces to the first surface, has a metal terminal having an end on the first surface side, contains metal particles, and has the end of the metal terminal and the line conductor. It is equipped with a bonding material that is interposed between the two. Further, it has a bonding structure having the above configuration between the end portion of the metal terminal and the line conductor.

According to the joint structure of one aspect of the present invention, the possibility of mechanical destruction of the joint structure due to thermal stress such as cracks in the joint material can be reduced.

According to the semiconductor package of one aspect of the present invention, since it has the bonding structure having the above configuration, it is possible to provide a semiconductor package having high mechanical and electrical connection reliability between the metal terminal and the signal line.

It is sectional drawing which shows the junction structure of embodiment of this invention. It is sectional drawing which shows the A part of FIG. 1 enlarged. It is sectional drawing which shows the B part of FIG. 1 enlarged. (A) is a perspective view of the semiconductor package according to the embodiment of the present invention, and (b) is a perspective view seen from the opposite side of (a). (A) is a plan view of the semiconductor package according to the embodiment of the present invention, and (b) is a cross-sectional view taken along line XX of (a). It is sectional drawing which enlarges and shows the main part in the joint structure of another embodiment of this invention. It is sectional drawing which shows the bonding structure of another embodiment of this invention. It is sectional drawing which shows the main part of the joint structure of another embodiment of this invention in an enlarged manner.

The bonded structure and the semiconductor package of the embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a cross-sectional view showing a joint structure according to an embodiment of the present invention, FIG. 2 is a cross-sectional view showing an enlarged portion A of FIG. 1, and FIG. 3 is an enlarged view of a portion B of FIG. It is sectional drawing which shows. Further, FIG. 4A is a perspective view of the semiconductor package according to the embodiment of the present invention, and FIG. 4B is a perspective view seen from the opposite side of FIG. 4A. 5 (a) is a plan view of the semiconductor package according to the embodiment of the present invention, and FIG. 5 (b) is a sectional view taken along line XX of FIG. 5 (a).

In the bonding structure C of the embodiment of the present invention, the metal terminal 1 having the end portion 1a, the line conductor 2, and the bonding material 3 interposed between the end portion 1a of the metal terminal 1 and the line conductor 2 are provided. Have. The end portion 1a of the metal terminal 1 and the line conductor 2 are joined to each other by the joining material 3. Further, the gap 4 is located along the bonding interface between the end portion 1a of the metal terminal 1 and the bonding material 3. When the bonding material 3 is conductive, the metal terminal 1 and the line conductor 2 are mechanically and electrically connected to each other via the bonding material 3.

The bonding structure C includes, for example, a metal terminal 1 for external connection, a line conductor 2 electrically connected to a semiconductor element, and a substrate 5 in which the metal terminal 1 and the line conductor 2 are arranged in a predetermined positional relationship. It is used for joining a metal terminal 1 and a line conductor 2 via a joining material 3 in a semiconductor package. In the semiconductor package 10 of the embodiment of the present invention, the metal terminal 1, the line conductor 2, the bonding material 3 interposed between the metal terminal 1 and the line conductor 2, the metal terminal 1 and the line conductor 2 are arranged. Further, it has the bonding structure C of the above-described embodiment between the metal terminal 1 and the line conductor 2.

Further, in the examples shown in FIGS. 4 and 5, the semiconductor package 10 further includes an insulating plate 6 in which the line conductor 2 is actually arranged and fixed to the substrate 5, and a submount bonded to the insulating plate 6. Has 7 and. The substrate 5 has a first surface 5a and a second surface 5b opposite to the first surface, and has a through hole 5c that penetrates the substrate 5 in the thickness direction between the first surface 5a and the second surface 5b. have. The lead terminal 1 passes through the substrate 5 from the second surface 5b to the first surface 5a through the through hole 5c. The end portion 1a of the lead terminal 1 is located on the first surface 5a side. The insulating plate 6 is located on the first surface 5a side of the substrate 5, so that the line conductor 2 is arranged on the first surface 5a side of the substrate 5. On the first surface 5a side of the substrate 5, the end portion 1a of the metal terminal 1 and the line conductor 2 are joined to each other via the joining structure C having the above configuration.

The semiconductor package 10 airtightly seals a semiconductor element (not shown) such as an optical semiconductor element. The semiconductor element is mounted on the insulating plate 6 and electrically connected to the line conductor 2. The first surface 5a side of the substrate 5 on which the semiconductor element is mounted is a metal case (CAN).
) (Not shown), a so-called TO (Transistor Outline) -CAN type semiconductor package is formed. When the semiconductor element is an optical semiconductor element, a metal case having an opening for input / output of an optical signal is used.

In the bonding structure C of the embodiment, the metal terminal 1 has a function as a conductive path for external connection in the semiconductor package 10 as described above, for example. In this case, the metal terminal 1 is an elongated strip-shaped or rod-shaped lead (pin) terminal. The metal terminal 1 is made of, for example, a metal material such as an iron-nickel-cobalt alloy, an iron-nickel alloy, or an alloy material containing copper. When the metal terminal 1 is made of, for example, an iron-nickel-cobalt alloy, the iron-nickel-cobalt alloy is subjected to metal processing appropriately selected from rolling, punching, cutting, etching, etc. on this ingot (lump). Can be manufactured by.

The metal terminal 1 may be one in which a plurality of metal terminals 1 are arranged side by side and fixed to the substrate 5, as in the examples shown in FIGS. 4 and 5, for example. In the examples shown in FIGS. 4 and 5, a pair of metal terminals 1 for signal transmission are arranged so as to penetrate the substrate 5. Each metal terminal 1 has an end portion 1a located on the first surface 5a side of the substrate 5.

In the examples shown in FIGS. 4 and 5, the ground terminal 8 is arranged alongside the pair of metal terminals 1. The ground terminal 8 can be manufactured by the same method using the same metal material as the metal terminal 1. Details of the configurations and functions of the metal terminal 1 and the ground terminal 8 in the semiconductor package 10 will be described later.

The metal terminal 1 is, for example, linear with a length of 1.5 to 22 mm and a diameter of 0.1 to 1 mm. For signal transmission, the diameter of each metal terminal 1 is 0.15, considering the mechanical strength of the pair of metal terminals 1, matching of characteristic impedance (hereinafter, simply referred to as impedance), and miniaturization of the semiconductor package 10. ~ 0.25 mm. When the diameter of the metal terminal 1 is 0.15 mm or more, it is easy to suppress bending of the metal terminal 1 when handling the semiconductor package 10, which is advantageous in improving workability. Further, when the diameter of the metal terminal 1 is 0.25 mm or less, the diameter of the through hole 5c through which the metal terminal 1 penetrates can be suppressed to be small, so that the substrate 5 can be downsized, that is, the semiconductor package 10 can be downsized. Is effective.

The line conductor 2 has a function as, for example, a conductor for connecting semiconductor elements in the semiconductor package 10. The electrical connection between the semiconductor element and the line conductor 2 is made via a low melting point brazing material such as a bonding wire or solder. In the case of a bonding wire, the semiconductor element is bonded to the line conductor 2 by sequentially bonding a bonding wire such as a gold wire or an aluminum wire to the semiconductor element (electrode) and the line conductor 2 by a bonding method such as a ball bonding method. Can be electrically connected to. The line conductor 2 and the metal terminal 1 are joined to each other via a bonding material 3 to form a conductive path that electrically connects a semiconductor element and an external electric circuit.

As described above, the line conductor 2 is formed on the surface of the insulating plate 6, for example. The insulating plate 6 is fixed to the first surface 5a side of the substrate 5, and the line conductor 2 is located on the first surface 5a side of the substrate 5. On the first surface 5a side, the end portion 1a of the metal terminal 1 is located on the line conductor 2, and both are joined to each other via a joining material 3 described later.

The line conductor 2 is a metal material appropriately selected from metal materials such as tungsten, molybdenum, manganese, copper, silver, gold, palladium, platinum, rhodium, nickel and cobalt, or a metal material of an alloy containing these metal materials. Is formed by. The line conductor 2 can be formed in the form of a metallized layer, a plating layer, a thin film layer, or the like. The line conductor 2 is formed on the insulating plate 6 as described above, and when it contains a thin layer of gold, copper, nickel, silver or the like, titanium, chromium, tantalum, niobium, nickel-chromium alloy, nitrided. It may further include an adhesive metal layer such as tantalum. The adhesion metal layer is located between the insulating plate 6 and the thin film layer, and has a function of improving the adhesion of the line conductor 2 to the insulating plate 6.

The thickness of the line conductor 2 is 0.1 in consideration of, for example, reduction of electrical resistance and suppression of internal stress.
It is set to about 5 μm. The thickness of the adhesion metal layer is set to about 0.01 to 0.2 μm in consideration of improving the adhesion to the insulating plate 6 and suppressing internal stress. The line conductor 2 may further include a diffusion suppression layer that suppresses mutual diffusion between the close contact metal layer and the thin film layer. The diffusion suppression layer can be formed of, for example, a metal material such as platinum, palladium, rhodium, nickel, or a titanium-tungsten alloy. The thickness of the diffusion suppression layer is set to about 0.05 to 1 μm in consideration of, for example, the suppression of mutual diffusion and the suppression of electrical resistance in the line conductor 2.

Further, when the line conductor 2 is arranged on the surface of the insulating plate 6 by the metallization method, it is appropriately selected from metal materials such as tungsten, molybdenum, manganese, copper, silver, gold, platinum and palladium. It may contain a metallic material. In this case, for example, the line conductor 2 can be formed by firing a metal paste prepared by kneading tungsten powder with an organic solvent, a binder, or the like with an insulating plate 6.

The insulating plate 6 is formed of, for example, a ceramic insulating material such as an aluminum oxide-based sintered body, an aluminum nitride-based sintered body, a silicon nitride-based sintered body, or a glass-ceramic sintered body. The insulating plate 6 can be manufactured as follows, for example, when it is made of an aluminum oxide sintered body. First, an appropriate organic solvent and solvent are added and mixed with raw material powders such as aluminum oxide, silicon oxide, calcium oxide and magnesium oxide to prepare a slurry. Next, the slurry is formed into a sheet by a doctor blade method, a calendar roll method, or the like to obtain a ceramic green sheet (hereinafter, also referred to as a green sheet). After that, the green sheet is punched into a predetermined shape, and if necessary, a plurality of green sheets are laminated and fired at a predetermined temperature of about 1300 to 1600 ° C. The insulating plate 6 can be manufactured by the above steps.

When the line conductor 2 is made of a metallized layer such as tungsten, a manufacturing method is used in which a metal paste for the metallized layer (line conductor 2) is printed on the surface of a green sheet to be an insulating plate 6 in a predetermined pattern and simultaneously fired. You may. In this case, the insulating plate 6 and the line conductor 2 can be integrally manufactured. Therefore, it is effective in improving the strength and productivity of the joint between the line conductor 2 and the insulating plate 6.

The bonding material 3 interposed between the end portion 1a of the metal terminal 1 and the line conductor 2 is made of, for example, a metal material such as silver, copper, gold and palladium, or a metal material such as an alloy containing these metal materials. Contains metal particles. The metal particles are bonded to each other by metal bonding to form a unified shape as a bonding material 3. Further, the metal particles are bonded to each other with the metal components contained in the metal terminal 1 and the line conductor 2, respectively. As a result, the metal terminal 1 and the line conductor 2 are joined via the joining material 3.

The void 4 located along the bonding interface between the end portion 1a of the metal terminal 1 and the bonding material 3 has a function of absorbing and relaxing the thermal stress generated between the metal terminal 1 and the bonding material 3, for example. doing. That is, since the gap 4 is located along the bonding interface between the end portion 1a of the metal terminal 1 and the bonding material 3, the surface portion of the metal terminal 1 can be easily deformed in the gap 4. By this deformation, for example, the thermal stress generated between the insulating plate 6 which is the base on which the line conductor 2 or the line conductor 2 is located and the metal terminal can be absorbed and relaxed. Therefore, the possibility of mechanical destruction of the joint structure C due to thermal stress, such as a crack in the joint material 3, can be reduced. That is, it is possible to provide a highly reliable joint structure C for electrical and mechanical connection between the metal terminal 1 and the line conductor 2.

The void 4 exists in an area ratio of about 5 to 30% of the bonding interface where the metal terminal 1 and the bonding material 3 face each other in consideration of the relaxation of the thermal stress described above. In other words, the bonding material 3 does not have to be actually bonded to the metal terminal 1 in an area of about 5 to 30% of the surface facing the end of the metal terminal 1. When the area ratio is about 5% or more, the thermal stress can be effectively absorbed and relaxed. Further, when the area ratio is 30% or less, the actual bonding area of the bonding material 3 with respect to the metal terminal 1 can be increased, and the bonding strength between the two can be effectively improved.

In the examples of FIGS. 1 and 2, the gap 4 is continuous and has a relatively large area, but the space 4 is not limited to this, and a plurality of smaller voids may be dispersed and exist. .. Further, the distance between the surface of the end portion 1a of the metal terminal 1 and the bonding material 3 in the gap 4 (that is, the size such as the height of the gap 4) is set to an arbitrary value in terms of relaxation of thermal stress. You can do it. That is, it suffices if there is a gap between the metal terminal 1 and the bonding material 3 in which the two are not directly bonded. The height and the like of the void 4 may be as narrow as the so-called submicron order in consideration of suppressing the entry of corrosive components such as water into the void 4.

The size of the height of the void 4 is determined by the particle size of the metal particles, the joining conditions such as the heating temperature at the time of joining, the material of the metal particles, and the size and direction of the external force such as gravity acting on the joining material 3 at the time of joining. The conditions of may be adjusted as appropriate. For example, if it is desired to increase the relaxation of the thermal stress on the insulating plate 6, the height of the void 4 and the like may be increased to improve the heat dissipation at the joint portion between the line conductor 2 and the bonding material 3.

In the example shown in FIG. 2, the gap 4 is located in a region (hereinafter, also referred to as a lower region) of the end portion 1a of the metal terminal 1 facing the line conductor 2 via the bonding material 3. In this case, the thermal stress can be effectively relieved in the lower region where the thermal stress tends to concentrate in the metal terminal 1 and the bonding material 3. Therefore, it is possible to obtain a joint structure C which is particularly advantageous for relaxing thermal stress and is effective for improving reliability.

In order to position the gap 4 in the lower region, for example, the lower region may face downward when the metal terminal 1 and the line conductor 2 are joined via the bonding material 3. The details are as follows.

The metal terminal 1 and the line conductor 2 are joined via the joining material 3 as follows, for example. First, particles of the above metal material such as silver (actually, an aggregate of a large number of particles) are kneaded together with an organic solvent and a binder to prepare a paste. Next, the end portion 1a of the metal terminal 1 is aligned with a predetermined portion of the line conductor 2 with this paste sandwiched between them, and temporarily fixed with a jig or the like. Then, these are heated in an electric furnace or the like to bond the metal particles in the paste. At this time, polymerization or the like may occur between the binder components. That is, the bonding material 3 may include the action of bonding by a polymer of organic components in addition to the metal bonding between metal particles. The temperature of joining with the paste containing the binder component is set to, for example, about 200 to 300 ° C.

From the behavior of metal particles and the like at the time of such joining, if the lower region faces downward at the time of joining the metal terminal 1 and the line conductor 2, in other words, the metal terminal 1 (end 1a) is connected to the joining material 3 by gravity. If the paste is located in a direction away from each other, a part of the bonding material 3 (paste) is separated from the end portion 1a of the metal terminal 1 by the action of the gravity, and a gap 4 is formed between the two. Can be done. Since the metal particles are bonded to each other in the state where the gap is formed, the gap 4 can be positioned between the end portion 1a of the metal terminal 1 and the line conductor 2.

Further, at this time, if the pastes contain organic components that polymerize with each other, the paste is cured at a relatively low temperature by the polymer of the organic components, so that the shape of the paste to be the bonding material 3 can be easily maintained. Therefore, it is possible to join the metal terminal 1 between the end portion 1a and the joining material 3 with the gap 4 included. Further, since the bonding can be performed at a relatively low temperature, it is effective for improving the workability of bonding the metal terminal 1 and the line conductor 2 via the bonding material 3 and the productivity of the bonding structure C and the semiconductor package C. ..

Further, the metal particles in the bonding material 3 are fine particles having a particle size of about 1 μm or less (so-called submicron particles, sub-nano particles, etc.) in consideration of the ease of bonding between the metal particles, the strength of bonding, and the like. It may be a nanoparticle) or a mixture of fine particles and micron-sized metal particles. The paste to be the bonding material 3 may contain an organic resin component that polymerizes with each other when such fine particles are used as metal particles. Examples of such an organic resin component include a polymerizable carboxylic acid derivative and the like.

Further, the bonding material 3 does not have to contain metal particles which are fine particles, and may be a polycrystalline body containing crystal particles such as silver or copper as metal particles. In this case as well, the voids 4 can be created by the crystal particles moving downward according to gravity.

Further, in the examples shown in FIGS. 2 and 3, the gap 4 is located only in the region (lower region described above) of the end portion 1a of the metal terminal 1 facing the line conductor 2 via the bonding material 3. doing. Also in this case, the thermal stress can be effectively relaxed in the lower region where the thermal stress is likely to be concentrated in the metal terminal 1 and the bonding material 3. Further, in this case, the void 4 does not exist other than the lower region. In other words, the bonding material 3 is directly bonded to the end portion 1a of the metal terminal 1 in a relatively wide area excluding the lower region.

That is, it is easy to secure the bonding area of the bonding material 3 with respect to the metal terminal 1 while making the relaxation of thermal stress effective. Therefore, in this case, the joint structure C is advantageous for relaxing the thermal stress and improving the joint strength, and can be effective for improving the joint strength and reliability between the metal terminal 1 and the line conductor 2.

Further, when the void 4 is located only in the lower region, the void 4 may be present on almost the entire surface of the lower region. Even if such a gap 4 exists, since the joint 3 is directly joined to the metal terminal 1 except in the lower region, it is possible to effectively secure the joint strength between the joint material 3 and the metal terminal 1. It's easy.

To position the void 4 only in the lower region, for example, the following may be performed. That is, as in the case where the void 4 is located in the lower region (when the void 4 may be located in a region other than the lower region), the lower region is directed downward and the paste used as the bonding material 3 is sandwiched between the pastes. The metal terminal 1 (end 1a) and the line body 2 are heated and joined by sandwiching the metal terminal 1 (end 1a). At this time, the conditions such as the content of the organic solvent in the paste, the particle size of the metal particles, the particle size distribution and the content, the temperature at the time of joining, the time required for joining, and the cooling time after joining are appropriately adjusted to lower the lower part. Make sure that no gap (void 4) is formed between the paste and the metal terminal 1 other than the region.

The condition in which gaps are likely to occur is, for example, the case where the viscosity of the paste is low, and the viscosity is adjusted by, for example, the content of the organic solvent. Further, there is a case where the bondability of the metal particles at the time of bonding is low and the time required for bonding is long, and this time is adjusted by, for example, the particle size of the metal particles. In addition, when the bonding temperature is high, that is, when metal particles are likely to aggregate or sinter during bonding, the bonding temperature is set so as not to exceed the temperature required for metal bonding between metal particles. To do.

FIG. 6 is an enlarged cross-sectional view showing a main part of the joint structure of another embodiment of the present invention. In FIG. 6, the same parts as those in FIGS. 1 to 5 are designated by the same reference numerals. In the example shown in FIG. 6, a thin layer 9 made of the same metal material as the metal particles is located on the surface of the metal terminal 1 exposed in the void 4. The thin layer 9 is, for example, a layered portion having a thickness of about 0.5 μm to 10 μm. The thin layer 9 may be located along substantially the entire surface of the metal terminal 1 facing the void 4, or may be located on the surface of the metal terminal 1 in contact with the bonding material 3. May be good. The presence of such a thin layer 9 can effectively reduce the possibility of corrosion of the metal terminal 1 due to the adhesion of moisture.

The thin layer 9 can be formed, for example, by adjusting the heating temperature and time at the time of joining the metal terminal 1 and the line conductor 2 via the bonding material 3 (the paste). For example, the above joining temperature may be set to about the upper limit (300 ° C., etc.) of the joining temperature of the paste serving as the joining material 3 so that the metal terminal 1 and the line conductor 2 are joined. Due to the heat at this time, components such as silver in the bonding material 3 wet and spread along the surface of the end portion 1a of the metal terminal 1 to form a thin layer 9.

FIG. 7 is a cross-sectional view showing a joining structure of another embodiment of the present invention. In FIG. 7, the same parts as those in FIGS. 1 to 5 are designated by the same reference numerals. In the example shown in FIG. 7, the joining material 3 is not joined to the pin terminal 1 in a wide range of the end portion 1a facing the line conductor 2 from the tip end (right end in FIG. 7) of the pin terminal 1. The gap 4 is located at the tip of the pin terminal 1. In this case, the joining material 3 smoothly forms a fillet from the center of the tip portion of the pin terminal 1 to the line conductor 2 facing the end portion 1a.

In the example shown in FIG. 7, the presence of the fillet can also improve the bonding strength of the bonding material 3 with respect to the line conductor 2. Further, also in this example, since the gap 4 is located between the bonding material 3 and the end portion 1a (tip portion) of the metal terminal 1, the thermal stress in the gap 4 portion can be easily relaxed. Therefore, the bonding structure C that is effective in improving the bonding strength and connection reliability between the line conductor 3 and the metal terminal 1 via the bonding material 3 can be obtained.

Further, in each of the above examples, when the metal particles are silver particles, it is advantageous in the following points. That is, it is advantageous for thermal conductivity in the bonding material 3 (that is, heat dissipation of the bonding structure C and the semiconductor package 10 including the bonding structure C), reduction of electrical resistance in the signal transmission line including the line conductor 2 and the metal terminal 1, and the like. is there. Further, there is an advantage that it is difficult to remelt even in a heat load process for mounting a semiconductor element or joining a metal case, and there is little outgassing.

The silver particles in this case may be so-called pure silver containing 99.9% by mass or more of silver, or may contain a trace amount of other components such as copper or gold. Further, not all of the metal particles need to be silver particles, and for example, both silver particles and copper particles may be contained in the metal particles.

When the metal particles are copper particles or contain copper particles, the possibility of ion migration is reduced, the economic efficiency is improved, etc., as compared with the case where all the metal particles are silver particles. Is advantageous.

As described above, the semiconductor package of the embodiment of the present invention has the following configuration. That is, the semiconductor package 10 of the present embodiment has a substrate 5 having a first surface 5a and a second surface 5b opposite to the first surface 5a, a line conductor 2 located on the first surface 5a side of the substrate 5, and a substrate. A metal terminal 1 that penetrates from the second surface 5b to the first surface 5a of 5 and has an end portion 1a on the first surface 5a side, and a metal particle, and includes the end portion 1a of the metal terminal 1 and a line conductor. It has a bonding material 3 interposed between the two. Further, the semiconductor package 10 of the present embodiment is the end portion 1 of the metal terminal 1.
A joint structure C having any of the above configurations is provided between a and the line conductor 2.

According to the semiconductor package 10 of the above-described embodiment, since the junction structure C having any of the above configurations is provided, the semiconductor package 10 having high mechanical and electrical connection reliability between the metal terminal 1 and the line conductor 2 is provided. be able to.

The first surface 5a side of the substrate 5 is the side sealed by the metal case described above. The end 1a of the semiconductor element and the metal terminal 1 is sealed in the space formed between the substrate 5 and the metal case. Further, in the examples shown in FIGS. 4 and 5, the sealing material (unsigned) is located in the through hole 5c of the substrate 5. The sealing material has a function of closing the gap between the metal terminal 1 and the through hole 5c. The sealing material is made of an insulating material such as a glass material or a ceramic material. Examples of such insulating materials include glasses such as borosilicate glass and soda glass, and those obtained by adding a ceramic filler for adjusting the coefficient of thermal expansion and the relative permittivity to these glasses. This insulating material can be appropriately selected in consideration of impedance matching (relative permittivity) in the metal terminal 1, reliability of sealing, and the like.

The submount 7 is provided on the first surface 5a of the substrate 5 and has a substrate mounting surface parallel to the first surface 5a. In the semiconductor package 10, the submount 7 has a function of conducting heat generated by electronic components mounted on the insulating plate 6 to the substrate 5. That is, the submount 7 has a function as a heat radiating material that dissipates heat to the outside of the semiconductor package 10.

The submount 7 may be integrally formed with the substrate 5, and may include a cooling member (for example, a Peltier element). When the submount 7 is integrally formed with the substrate 5, the submount 7 is made of the same metal material as the substrate 5. As a result, the heat dissipation property of the semiconductor package 10 is effectively ensured.

The present invention is not limited to the examples of the above embodiments, and various modifications can be made within the scope of the gist of the present invention.

For example, as shown in FIG. 8, the gap 4 may be located in a space closed by the bonding material 3. As a result, the thermal stress generated between the metal terminal 1 and the insulating plate 6 can be alleviated, and at the same time, the possibility of corrosion of the metal terminal 1 due to the adhesion of moisture can be effectively reduced.

1 ・ ・ Metal terminal 1a ・ ・ End 2 ・ ・ Line conductor 3 ・ ・ Bonding material 4 ・ ・ Void 5 ・ ・ Substrate 5a ・ ・ First surface 5b ・ ・ Second surface 5c ・ ・ Through hole 6 ・ ・ Insulation plate 7 ... Submount 8 ... Ground terminal 9 ... Thin layer
10 ... Semiconductor package

Claims (6)

With metal terminals with ends,
With the line conductor where the end of the metal terminal is located,
It contains metal particles and includes a bonding material interposed between the end of the metal terminal and the line conductor.
A bonding structure in which voids are located along the bonding interface between the end of the metal terminal and the bonding material. The bonding structure according to claim 1, wherein the gap is located in a region of the end of the metal terminal facing the line conductor via the bonding material. The joining structure according to claim 2, wherein the gap is located only in a region of the end of the metal terminal that faces the line conductor via the joining material. The bonding structure according to any one of claims 1 to 3, wherein a thin layer made of the same metal material as the metal particles is located on the surface of the metal terminal exposed in the void. The bonding structure according to any one of claims 1 to 4, wherein the metal particles are silver particles. A substrate having a first surface and a second surface opposite to the first surface,
A line conductor located on the first surface side of the substrate and
A metal terminal that penetrates from the second surface to the first surface of the substrate and has an end on the first surface side.
It contains metal particles and includes a bonding material interposed between the end of the metal terminal and the line conductor.
A semiconductor package having the bonding structure according to any one of claims 1 to 5, between the end of the metal terminal and the line conductor.

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