JP2012227482A - Electronic component mounting package and electronic device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: an electronic component mounting package with high reliability; and an electronic device using the same.SOLUTION: An electronic component mounting package includes: a substrate 1 having an electronic component mounting section 1a disposed on an upper surface of the substrate, and a through hole 1b extended between the upper surface and a lower surface of the substrate; a sealing material 2 loaded in the through hole 1b; and an upper end that protrudes upward from the upper surface of the substrate 1, and a lower end that protrudes downward from the lower surface of the substrate 1. The upper end and the lower end extend through the sealing material 2, and are fixed to the substrate 1. The electronic component mounting package includes terminals 3 configured to electrically connect electronic components therethrough. The sealing material 2 includes a recess 2a formed so as to surround the terminals 3.

Description

  The present invention relates to an electronic component mounting package for mounting and storing an electronic component such as an optical semiconductor element used in the field of optical communication, for example, and an electronic apparatus using the same.

  In recent years, for example, the demand for high-speed communication at a transmission distance of 40 km or less is rapidly increasing, and research and development on high-speed and large-capacity information transmission is being advanced. In particular, increasing speed of electronic devices such as semiconductor devices that receive and transmit optical signals using optical communication devices has been attracting attention, and the issue of increasing the output and speed of optical signals by electronic devices to improve transmission capacity It has been researched and developed as being.

  As a package on which an electronic component such as an optical semiconductor element used in the field of optical communication or the like is mounted, a base having a through hole, a sealing material filled in the through hole, a sealing material penetrating the sealing material, and fixed to the base Some of them have terminals. The electronic component is mounted on the upper surface of the base and is covered with, for example, a lid.

JP-A-8-130266

  With respect to the above-described package, a part of the sealing material is attached to the terminal so as to spread out on the terminal at the joint portion of the sealing material with the terminal, and a meniscus portion may be formed. This meniscus part is from the terminal surface of the sealing material adhering to the periphery of the terminal as it goes toward the upper end if it is on the upper surface side of the substrate and toward the lower end portion if it is on the lower surface side of the substrate. Since the thickness of the package becomes small, for example, the stress caused by the difference in the thermal expansion coefficient between the substrate and the sealing material may cause a crack, thereby impairing the airtightness of the package.

  According to one aspect of the present invention, the electronic component mounting package has an upper surface and a lower surface, and an electronic component mounting portion provided on the upper surface and a through hole provided from the upper surface to the lower surface A base material including a sealing material filled in the through-hole, an upper end projecting upward from the top surface of the base material, and being fixed to the base material through the sealing material, and the base material A lower end projecting downward from the lower surface, and a terminal to which the electronic component is electrically connected, and the sealing material has a recess formed to surround the terminal. It is characterized by that.

  According to another aspect of the present invention, the recess is formed apart from the terminal.

  According to another aspect of the present invention, an electronic device includes the electronic component mounting package of the present invention having the above-described configuration, the electronic component mounted on the mounting portion of the electronic component mounting package, the electronic component, and the electronic component. And a lid joined to the upper surface of the base so as to cover the through-hole.

  According to one aspect of the present invention, an electronic component mounting package includes a sealing material filled in a through-hole provided in a base, and a terminal that passes through the sealing material and is fixed to the base. The sealing material has a recess formed so as to surround the terminal, and due to the stress applied to the sealing material from the inner wall of the through hole due to the difference in thermal expansion coefficient between the base and the sealing material, Even if a crack is generated at the end of the joint portion with the terminal in the sealing material, the progress of the crack is suppressed on the wall surface of the recess, and the crack does not spread, and the reliability is high.

  According to another aspect of the present invention, the electronic component mounting package having the above-described configuration has a protruding shape in which the periphery of the terminal of the sealing material surrounds the terminal because the recess is formed apart from the terminal. The position of the stress applied to the sealing material from the inner wall of the through-hole due to the difference in thermal expansion coefficient between the sealing material and the sealing material shifts from the end of the joining portion with the terminal of the sealing material, and the joint portion with the terminal in the sealing material It becomes difficult for cracks to enter the end portions of the, and the reliability becomes higher.

  According to another aspect of the present invention, an electronic device includes an electronic component mounted on the mounting portion of the electronic component mounting package having the above configuration, and a lid bonded to the upper surface of the base so as to cover the electronic component and the through hole. By having the body, it becomes highly reliable.

It is a perspective view which shows an example of embodiment of the electronic device of this invention. It is sectional drawing which shows the cross section in the AA of the electronic device shown by FIG. (A) is the enlarged view of the A section of the electronic device shown in FIG. 2, (b), (c) is the principal part enlarged view of the other example of the same electronic device. It is a bottom view which shows an example of the lower surface of the electronic device of this invention shown by FIG. It is a perspective view which shows an example of embodiment of the electronic device of this invention. It is sectional drawing which shows the cross section in the AA of the electronic device shown by FIG. (A) is an enlarged view of the A part of the electronic device shown in FIG. 6, and (b) and (c) are enlarged views of the main part of another example of the same electronic device. It is a bottom view which shows an example of the lower surface of the electronic device of this invention shown by FIG. It is an enlarged view of the protrusion part shown by FIG.

  An electronic component mounting package and an electronic apparatus using the same according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  1 to 8, 1 is a base, 1a is a mounting portion, 1b is a through hole, 1c is a lid joint portion, 2 is a sealing material, 2a is a recess formed in the sealing material 2, 3 is a terminal, 3a is a signal terminal through which a high-frequency signal flows in the terminal 3, 3b is a DC terminal in which no high-frequency signal flows in the terminal 3, 4 is an electronic component, 4a is a circuit board, 4b is a relay board, 5 is a lid, 6 Is a temperature control element, 7 is a bonding wire, 8 is a monitor PD element, 9 is a reflecting mirror, and 10 is a temperature monitor element.

  In the example shown in FIGS. 1 and 5, the electronic component 4 is mounted via a temperature control element 6 such as a Peltier element and a circuit board 4a, with the central portion of the upper surface of the substrate 1 being a mounting portion 1a. One terminal of the electronic component 4 is electrically connected to the wiring on the circuit board 4 a by a bonding wire 7. The upper end portion of the signal terminal 3a and the signal line of the relay board 4b are electrically connected by a bonding material such as a brazing material, and the signal line on the upper surface of the relay board 4b and the wiring of the circuit board 4a are electrically connected by the bonding wire 7. As a result, the electronic component 4 and the signal terminal 3a are electrically connected. The other terminal of the electronic component 4 is electrically connected to one of the DC terminals 3b functioning as the ground via the wiring of the circuit board 4a. Thereby, the signal terminal 3a functions as a transmission path for transmitting an input / output signal between the electronic component 4 and an external electric circuit (not shown).

  In the example shown in FIGS. 1 and 5, an example in which the main electronic component 4 is an LD element is shown. On the circuit board 4a, a PD element 8 for monitoring the oscillation state of the LD element, LD There is a reflecting mirror 9 for reflecting the laser light oscillated from the element in the vertical direction from the upper surface of the circuit board 4a, and a temperature monitoring element 10 for measuring the temperature on the circuit board 4a and feeding it back to the temperature control element 6. It is installed. In addition to the through hole 1b for fixing the signal terminal 3a, the base 1 is formed with three through holes 1b, and two DC terminals 3b are fixed to the base 1 by the sealing material 2 respectively. The end of the DC terminal 3b protrudes from the first through hole 1b formed in the first base 1. The DC terminal 3b is for supplying power to the temperature control element 6, the monitor PD 8, and the temperature monitor element 10 in addition to the above-described ground.

  In FIGS. 1 and 5, the lid 5 is shown removed so that the state where the electronic component 4 and the like are mounted can be seen. However, as shown in the example shown in FIG. The lid 5 as shown is joined to the lid joint 1c by welding or brazing. In the example shown in FIGS. 2 and 6, the lid 5 having a window portion in which a translucent member for allowing laser light reflected vertically upward from the upper surface of the substrate 1 by the reflecting mirror 9 to pass is fitted. An example is shown.

  In the example shown in FIGS. 1, 2, 5, and 6, one electronic component 4 is mounted on the mounting portion 1 a of the base 1 via the circuit board 4 a and the temperature control element 6. However, a plurality of electronic components 4 may be mounted, or may be mounted directly on the mounting portion 1a of the base 1 without using the circuit board 4a and the temperature control element 6, or the bonding wires 7 may The component 4 and the signal terminal 3a may be directly connected. Also, the number of signal terminals 3a may be plural according to the number of electronic components 4 and the number of electrodes of the electronic components 4. The number of DC terminals 3b is also determined according to the number of temperature control elements 6, monitor PDs 8, temperature monitor elements 10, and the like.

  As shown in FIGS. 1 to 8, the electronic component mounting package in the present embodiment has an upper surface and a lower surface, and is provided from the upper surface to the lower surface of the electronic component mounting portion 1a provided on the upper surface. The base 1 including the through-hole 1b formed, the sealing material 2 filled in the through-hole 1b, the sealing material 2 is fixed to the base 1 through the sealing material 2, and protrudes upward from the upper surface of the base 1 And a terminal 3 to which an electronic component is electrically connected. The sealing material 2 surrounds the terminal 3. It has the recessed part 2a formed, It is characterized by the above-mentioned.

  With such a configuration, due to the stress applied to the sealing material 2 from the inner wall of the through hole 1b due to the difference in the behavior of the thermal expansion coefficient between the base 1 and the sealing material 2, the end of the joint portion with the terminal 3 in the sealing material 2 Even if there is a crack in the portion, the progress of the crack is suppressed on the wall surface of the recess 2a and the crack does not spread, and a highly reliable electronic component mounting package is obtained. This makes it necessary to use a material with high thermal conductivity for the substrate 1 when using a high-power element, but it cannot be used because it does not match the thermal expansion coefficient of the sealing material 2, or the impedance is matched with 50Ω. In the case where it is desired to use the sealing material 2 having a low dielectric constant, but cannot be used because it does not match the thermal expansion coefficient of the substrate 1 having good thermal conductivity, it can be used as long as it has a slight difference in thermal expansion coefficient. As a result, the degree of freedom in design increases.

Further, in the electronic component mounting package of the present embodiment, as in the example shown in FIGS. 1 to 8, the through hole 1b is formed in an oval shape, and a plurality of terminals 3 are sealed in the through hole 1b. When the plurality of terminals are formed in the same through-hole by fixing with the material 2 and the sealing material 2 has a plurality of recesses 2 a formed so as to surround the plurality of terminals 3, respectively. Since the stress applied to the plurality of terminals 3 from the inner surface of the through hole 1b of the substrate 1 is uneven, the sealing material 2 is more prone to cracks starting from the weaker portions of the sealing material 2. However, if the recess 2a is formed, the progress of cracks on the wall surface of the recess 2a is suppressed by the same principle as described above, and the cracks do not spread, resulting in a highly reliable electronic component mounting package. In the example, two terminals 3 are fixed in the through hole 1b, but three or more terminals 3 may be fixed in the through hole 1b. As a result, a large number of terminals can be air-tightly penetrated by a substrate having the same area, so that more terminals can be formed when the substrate 1 having the same dimensions is used. With the number of terminals 3, the base body 1 can be made smaller, and the degree of freedom in design becomes higher. In the case where a plurality of terminals 3 are provided in one through-hole 1b, and there is no recess 2a of the sealing material 2 in the electronic component mounting package of this embodiment, the terminals in the sealing material There is a possibility that cracks are generated at the end of the joint portion and the progress of the crack of the sealing material is not suppressed, and the airtightness of the package is impaired.

  Further, in the electronic component mounting package of the present embodiment, the recess 2 a is formed away from the terminal 3.

  With such a configuration, the periphery of the terminal of the sealing material 2 has a protruding shape surrounding the terminal 3, and stress applied to the sealing material 2 from the inner wall of the through hole 1b due to the difference in thermal expansion coefficient between the base 1 and the sealing material 2 Is shifted from the end of the joint portion of the sealing material 2 to the terminal 3 and the end portion of the joint portion of the sealing material 2 to the terminal 3 is less likely to crack, so that a more reliable electronic component is mounted. It becomes a package for.

  Further, in the electronic component mounting package of the present embodiment, as in the example shown in FIGS. 5 to 8, the through hole 1 b is formed in an oval shape as in the example shown in FIGS. 1 to 4. Then, a plurality of terminals 3 are fixed with a sealing material 2 in the through-hole 1b, and the sealing material 2 is spaced apart from the terminals 3 so as to surround each of the plurality of terminals 3, and a plurality of recesses 2a are formed. Thus, when a plurality of terminals are formed in the same through-hole, the stress applied to the plurality of terminals 3 from the inner surface of the through-hole 1b of the substrate 1 becomes uneven, so that the strength of the sealing material 2 is increased. Cracks are more likely to occur in the sealing material 2 starting from the weak part, but if the recess 2a is formed away from the terminal 3, the stress applied to the sealing material 2 is dispersed by the same principle as described above. As a result, the stress applied to the joining end portion of the sealing material 2 and the terminal 3 is reduced. The cracks are hardly enters, a more highly reliable electronic component mounting package. In the example, two terminals 3 are fixed in the through hole 1b, but three or more terminals 3 may be fixed in the through hole 1b as in the example shown in FIGS. .

  The electronic device according to the present embodiment has high reliability because the electronic component 4 is mounted on the mounting portion 1a of the electronic component mounting package having the above-described configuration and the lid body 5 is joined to the lid joint portion 1c. Become.

  In the electronic device according to the present embodiment, when the electronic component 4 is mounted via the temperature control element 6 in the above configuration, the temperature of the electronic component 4 can be kept constant by the temperature control element 6. Since the characteristic change of the electronic component 4 caused by the temperature change is eliminated, the characteristic becomes more stable.

The base body 1 has a mounting portion 1a for the electronic component 4 at the center of the upper surface, and also has a function of radiating heat generated by the mounted electronic component 4 to the outside of the package. Therefore, the substrate 1 is preferably made of a metal having good thermal conductivity. What is close to the thermal expansion coefficient of the electronic component 4 to be mounted or the circuit board 4a made of ceramic is preferable, and as an inexpensive one, for example, an iron-based alloy such as an Fe-Mn alloy, a metal such as pure iron, Copper (Cu), a copper-based alloy, or Fe-Ni-Co alloy is selected when the amount of heat generated is small. More specifically, there is an SPC (Steel Plate Cold) material (thermal conductivity: 80 W / m · K) of Fe 99.6 mass% -Mn 0.4 mass%. For example, when the substrate 1 is made of an Fe—Mn alloy, the ingot (lumb) of the alloy is manufactured into a predetermined shape by applying a metal processing method such as rolling or punching, and the through-hole 1b is formed by drilling or mold. It is formed by punching. Moreover, when the base | substrate 1 is a shape which has a protrusion part as the mounting part 1a, it can form by cutting or pressing.

The substrate 1 is a flat plate having a thickness of 0.5 to 1 mm, and the shape thereof is not particularly limited. For example, the substrate 1 is a disc having a diameter of 3 to 6 mm and a half of a circle having a radius of 1.5 to 8 mm. A disc shape, a square plate shape with a side of 3 to 15 mm, or the like.

  The thickness of the substrate 1 is preferably 0.5 mm or more. When the thickness is less than 0.5 mm, when the metal lid 5 for protecting the electronic component 4 is bonded to the upper surface of the metal substrate 1, the substrate 1 may be bent depending on the bonding conditions such as the bonding temperature. It becomes easy to deform. Further, if the thickness exceeds 1 mm, the thickness of the electronic component mounting package and the electronic device becomes unnecessarily thick, and it is difficult to reduce the size. Therefore, the thickness of the substrate 1 is preferably 1 mm or less.

A plurality of through holes 1b having a diameter of 0.6 to 2.6 mm formed from the upper surface to the lower surface of the base 1 are provided around the mounting portion 1a. The diameter of the through hole 1b through which the signal terminal 3a passes is set such that a coaxial wiring having a characteristic impedance of 50Ω is formed by the signal terminal 3a passing through the center. For example, if the diameter of the signal terminal 5 is 0.2 mm and the relative permittivity of the sealing material 2 is 6.8, the diameter of the through hole 1b may be 1.75 mm. With respect to the through hole 1b through which the DC terminal 3b passes, the DC terminal 8 is not affected by the characteristic impedance, so that the DC terminal 8 and the base 1 are not short-circuited so that the DC terminal 3b and the inner surface of the through hole 1b are not short-circuited. What is necessary is just to form in the magnitude | size of about 0.6 mm in which the sealing material 3 of sufficient thickness (about 0.2 mm) enters. On the contrary, the through hole 1b may be made larger than the above dimension, and a plurality of DC terminals 3b may be penetrated as in the example shown in FIGS. In this case, a sufficient interval (about 0.3 mm) is provided between the DC terminals 3b of φ0.2 mm along the long diameter of the through hole 1b, and the pitch between the DC terminals 3b is 0.5 mm. Can form two DC terminals with a short diameter of 1.1 mm and 0.6 mm. When the two independent through holes 1b are formed, the pitch of the DC terminals 3b is required to be about 0.9 mm. Therefore, by forming a plurality of DC terminals 3b in one through hole 1b, the density of the DC terminals 3b is increased. become able to. As described above, the number of signal terminals 3a is determined according to the number of electronic components 4 and the number of terminals of electronic component 4, and the number of DC terminals 3b is determined according to the number of other elements other than electronic component 4. Therefore, the through hole 1b may be appropriately formed accordingly.

Further, the surface of the substrate 1 has a thickness of 0.5 to 9 μm, which has excellent corrosion resistance and excellent wettability with the brazing material.
It is preferable that the Ni layer of m and the Au layer having a thickness of 0.5 to 5 μm are sequentially deposited by plating. Thereby, it is possible to effectively prevent the base body 1 from being oxidatively corroded, and the electronic component 4, the circuit board 4a, the lid body 5 and the like can be brazed to the base body 1 in a good manner.

  The terminal 3 of the signal terminal 3a and the DC terminal 3b is made of a metal such as Fe-Ni-Co alloy or Fe-Ni alloy. For example, when the signal terminal 3a is made of Fe-Ni-Co alloy, an ingot ( By applying a metal working method such as rolling or punching to the lump), the lump is produced into a linear shape having a length of 1.5 to 22 mm and a diameter of 0.1 to 0.5 mm.

  The signal terminal 3a and the DC terminal 3b are fixed via the sealing material 2 so that at least the lower end portion protrudes from the through hole 1b of the base body 1 by about 1 to 20 mm, and the upper end portion is set to 0 to 0 from the through hole 1b of the base body 1. Project about 2 mm.

  The ground terminal may be connected to the lower surface of the base 1 using a brazing material or the like.

The sealing material 2 is made of an inorganic material such as glass or ceramics, and ensures an insulation interval between the terminal 3 of the signal terminal 3a and the DC terminal 3b and the base 1, and the signal terminal 3a and the DC terminal 3b are formed in the through hole 1b. Has the function of fixing. Examples of such a sealing material 2 include glass such as borosilicate glass and soda glass, and a glass filler added with a ceramic filler for adjusting the thermal expansion coefficient and relative dielectric constant of the sealing material 2. The relative dielectric constant is appropriately selected for impedance matching. Examples of the filler that lowers the dielectric constant include lithium oxide. For example, in order to set the characteristic impedance to 50Ω, if the outer diameter of the signal terminal 3a is 0.2 mm, the inner diameter of the through hole 1b is set to 1.75 mm, and the sealing material 2
The one having a relative dielectric constant of 6.8 may be used. Alternatively, when the outer diameter of the signal terminal 3a is 0.25 mm, the inner diameter of the through hole 1b is 2.2 mm, and the relative permittivity of the sealing material 2 is 6.8. Similarly, if the outer diameter of the signal terminal 3a is 0.25 mm, the inner diameter of the through hole 1b may be 1.65 mm and the relative permittivity of the sealing material 2 may be 5. If the relative permittivity of the sealing material 2 is 4, the characteristic impedance is 50Ω when the inner diameter of the through hole 1b is 1.35 mm in the case of the same outer diameter of 0.25 mm.

  As the relative dielectric constant of the sealing material 2 is smaller, the impedance can be matched to 50Ω even if the through hole 1b is made smaller. As a result, the base 1 is more effectively reduced in size and more compact. An electronic component storage package can be obtained.

  The sealing material 2 for fixing the DC terminal 3b does not need to consider impedance in particular, and may be any material that can be hermetically sealed to fix the DC terminal 3b, so that the signal terminal 3a is fixed. The sealing material 2 may not be the same. In order to fix the DC terminal 3b at the same time as fixing the signal terminal 3a, it is preferable to use the same glass as the sealing material 2 for fixing the signal terminal 3a or a glass having the same melting point.

When the sealing material 2 is made of glass, a powder pressing method or extrusion is performed so that the inner diameter is larger than the outer diameter of the signal terminal 3a or the DC terminal 3b and the outer diameter is smaller than the inner diameter of the through hole 1b. A glass sealing material 2 molded by a molding method or the like is inserted into the through hole 1 b, and the signal terminal 3 a or the DC terminal 3 b is inserted into the sealing material 2. Then, the member assembled as described above is placed on a receiving jig in which a hole is formed so that the terminal 3 is placed at a predetermined depth at a predetermined position, and the terminal 3 is placed at a predetermined position from above. A heavy stone jig with a through hole through which was inserted was placed. At this time, the sealing material 2 is at least in one of the receiving jig and the weight stone jig so as to form the concave portion 2a so as to surround the terminal 3 at a portion to be a joining end portion of the terminal 3 and the sealing material 2. An annular protrusion is formed so as to surround the terminal 3. Thereafter, the sealing material 2 is melted by heating to a predetermined temperature, whereby the signal terminal 3a or the DC terminal 3b is embedded in the sealing material 2 and insulated from the base body 1 in the through-hole 1b and fixed in an airtight manner. In addition, the sealing material 2 has a structure having a recess 2 a formed so as to surround the terminal 3, and the inner diameter of the annular protrusion is larger than the diameter of the terminal 3. The concave portion 2 a of the stopper 2 is formed so as to be separated from the terminal 3, and has a projecting shape (protruding portion 2 b) in which the periphery of the terminal 3 of the sealing material 2 surrounds the terminal 3. At this time, if the height of the protruding portion 2b is 0.1 mm or more from the bottom surface of the concave portion 2a, the position of the stress applied to the sealing material 2 from the inner wall of the through hole 1b is surely the joining end of the sealing material 2 to the terminal 3 Since it becomes difficult for a crack to enter the sealing material 2 by shifting from the portion, it is preferable.

In FIGS. 3A and 7A, the recesses 2a are formed on the upper and lower surfaces of the sealing material 2 of all the terminals 3, but at the connection portion of the signal terminal 3a with the relay substrate 4b. Since the impedance tends to increase due to the presence of the recess 2a, a loss tends to occur in the conversion from the coaxial structure to the microstrip structure at the portion where the recess 2a of the base 1 of the signal terminal 3a is formed. 3 (b) and FIG. 7 (b), at least in the signal terminal 3a, the recess 2a is not formed in the upper surface direction of the base 1, and the recess 2a is only formed in the lower surface direction. Is preferable in terms of signal transfer characteristics. In order to join the joining end portion of the signal terminal 3a and the sealing material 2 vertically (substantially without generating a meniscus), the clearance of the insertion hole of the terminal 3 formed in the receiving jig can be reduced. However, if the clearance is reduced, the workability is lowered. For example, if the following is performed, the clearance can be reduced without reducing the workability. If the receiving jig is made of a material having a thermal expansion coefficient smaller than the thermal expansion coefficient of the terminal 3, it is a hole through which the terminal 3 can be inserted without difficulty when assembling parts at room temperature, but at a temperature at which the sealing material 2 is melted. Since the gap between the hole 3 and each jig hole can be almost eliminated, the meniscus formed by the sealing material 2 flowing into the gap between each jig hole and the terminal 3 can be reduced. For example, even when the signal terminal 3a is made of a relatively low thermal expansion material such as an Fe50Ni (thermal expansion coefficient: 9.9 × 10 ⁻⁶ / K) alloy, the receiving jig is made of carbon (thermal expansion coefficient: 4 × 10 ⁻⁶ / K). It can be realized by manufacturing in K). In this case, since the meniscus is formed only at the connection end portion of the sealing material 2 and the terminal 3 on the lower surface side of the base body 1, the recess 2 a is formed on the lower surface of the sealing material 2 of all the terminals 3. .

  Further, as shown in FIGS. 3C and 7C, when one signal terminal 3a is fixed to the center of the circular through hole 1b with the sealing material 2, the sealing is performed. Even if a meniscus is formed at the joint end of the stopper 2 and a thin layer of the sealant 2 is formed on the terminal 3, the stress is applied evenly to the terminal from the inner surface of the circular through-hole of the base. Therefore, the recess 2a may be formed only in the sealing material 2 of the through hole 1b forming the plurality of DC terminals 3b.

Here, as will be described with reference to FIG. 9, in the recess 2 a and the protrusion 2 b that concentrically surround the terminal 3, the recess depth (H) and the radius of curvature between the bottom surface of the recess and the inner wall surface ( r), the protrusion height (T) and the protrusion diameter (D) are important. The recess depth (H) refers to the distance from the outside of the recess 2a to the bottom surface of the recess. The radius of curvature (r) refers to the degree of curvature of the curved portion formed between the bottom surface of the recess 2a and the inner wall surface. The protrusion height (T) refers to the distance from the bottom surface of the recess 2a to the upper end of the protrusion 2b. The protruding diameter (D) refers to the diameter of the protruding portion 2b. The ratio of the radius of curvature (r) between the protrusion height (T) and the inner wall surface of the recess is preferably 2 <T / r. When T / r ≦ 2, the stress applied to the sealing material 2 from the inner surface of the through hole 1b of the base body 1 is transmitted from the bottom surface of the recess 2a along the radius of curvature (r) to the upper end of the protrusion 2b. Stress is applied to the thin portion of the sealing material 2 at the tip of the meniscus, and cracks are likely to occur in the thin portion of the sealing material 2, but when T / r1 is greater than 2, the radius of curvature starts from the bottom surface of the recess 2a. Therefore, since the height at which the stress is transmitted is limited, the stress is not transmitted to the portion where the thickness of the sealing material 2 at the tip of the meniscus is thin. . Preferably, 3 <T / r1 is more preferable. Also, the protruding diameter (
D) is preferably a protruding diameter (D) that satisfies D−Dt> 0.05 mm, where Dt is the diameter of the terminal 3. When D−Dt ≦ 0.05 mm, the thickness of the sealing material 2 of the protruding portion 2b becomes thin, so that the strength of the sealing material 2 of the protruding portion 2b decreases, and cracks tend to occur. In general, the signal terminal 3a is connected to an external terminal by a flexible board. In this case, the impedance mismatch can be reduced by connecting the flexible board to the sealing material 2 with as little gap as possible. Although the deterioration of the transmission is reduced, a gap is easily formed between the flexible substrate and the sealing material 2 by the meniscus formed at the joining end portion of the sealing material 2 shown in FIG. As shown in the example of FIG. 9, the protrusion height (T) is made lower than the recess depth (H) by the height at which the meniscus of the encapsulant 2 is formed, so that even if the meniscus is formed, the sealing is performed. What is necessary is just to set it as the structure which can make the clearance gap between the child material 2 and a flexible substrate small. Further, if the depth (H) of the recess is larger than the protrusion height (T), the protrusion 2b will not collide with other parts during handling, and this is preferable. In order to form the recess depth (H) larger than the protrusion height (T), the inner height of the inner diameter of the annular projection formed on the carbon jig when the sealing material 2 is heated and joined to the through hole 1b. If the height is formed higher than the outside of the protrusion, the protrusion 2b of the finished sealing material 2 can be formed lower than the periphery of the recess 2a.

The electronic component 4 is mounted on the mounting portion 1a of the electronic component mounting package of the present embodiment, and the lid body 5 is joined to the lid joint portion 1c of the base body 1. Become.

  The electronic device according to the present embodiment has high reliability because the electronic component 4 is mounted on the mounting portion of the electronic component mounting package according to the present embodiment having the above-described configuration, and the lid 5 is joined to the lid joint 1c. It will be expensive.

  As the electronic component 4, an optical semiconductor element such as an LD (laser diode) or PD (photodiode), a semiconductor element including a semiconductor integrated circuit element, a piezoelectric element such as a crystal resonator or a surface acoustic wave element, or A pressure sensor element, a capacitive element, a resistor, etc. are mentioned.

The insulating substrates of the circuit board 4a and the relay substrate 4b are made of a ceramic insulating material such as an aluminum oxide (alumina: Al ₂ O ₃ ) sintered body, an aluminum nitride (AlN) sintered body, and the insulating substrate is, for example, oxidized. If it is made of an aluminum sintered body, first add and mix an appropriate organic solvent and solvent to the raw material powder such as alumina (Al ₂ O ₃ ), silica (SiO ₂ ), calcia (CaO), magnesia (MgO), etc. Then, it is made into a mud shape, and this is formed into a sheet shape by a doctor blade method, a calender roll method or the like to obtain a ceramic green sheet (hereinafter also referred to as a green sheet). Thereafter, the green sheet is punched into a predetermined shape, and a plurality of sheets are laminated as necessary, and the green sheet is fired at a temperature of about 1600 ° C. Thereafter, the main surface of the insulating substrate may be polished as necessary.

  By forming the wiring conductor on the upper surface of the insulating substrate by using the vapor deposition method and the photolithography method, the circuit substrate 4a and the relay substrate 4b are obtained. The wiring conductor is composed of a conductor layer having a three-layer structure in which, for example, an adhesion metal layer, a diffusion prevention layer, and a main conductor layer are sequentially laminated. Further, the wiring conductor through which the high-frequency signal is formed on the circuit board 4a and the relay board 4b is a line whose characteristic impedance is matched to 50Ω, for example, similarly to the through hole 1b portion of the signal terminal 3a.

From the viewpoint of improving the adhesion with an insulating substrate made of ceramics or the like, the adhesion metal layer is made of titanium (Ti), chromium (Cr), tantalum (Ta), niobium (Nb), nickel-chromium (Ni- It is preferable that at least one kind of metal having a coefficient of thermal expansion close to that of ceramics, such as a Cr) alloy and tantalum nitride (Ta ₂ N), and the thickness thereof is preferably about 0.01 to 0.2 μm. If the thickness of the adhesion metal layer is less than 0.01 μm, it tends to be difficult to firmly adhere the adhesion metal layer to the insulating substrate. If the thickness exceeds 0.2 μm, the adhesion metal layer is insulated by the internal stress during film formation. It tends to become easy to peel off.

  In addition, the diffusion preventing layer is made of platinum (Pt), palladium (Pd), rhodium (Rh), nickel (Ni), Ni—Cr alloy, from the viewpoint of preventing mutual diffusion between the adhesion metal layer and the main conductor layer. It is preferably made of at least one metal having good thermal conductivity such as Ti—W alloy, and the thickness is preferably about 0.05 to 1 μm. If the thickness of the diffusion preventing layer is less than 0.05 μm, defects such as pinholes tend to be generated and it becomes difficult to perform the function as the diffusion preventing layer. If the thickness exceeds 1 μm, the diffusion preventing layer is caused by internal stress during film formation. There is a tendency to easily peel from the adhesion metal layer. When a Ni—Cr alloy is used for the diffusion preventing layer, the adhesion metal layer can be omitted because the Ni—Cr alloy has good adhesion to the insulating substrate.

Furthermore, the main conductor layer is preferably made of at least one of gold (Au), Cu, Ni, and silver (Ag) having a low electric resistance, and the thickness is preferably about 0.1 to 5 μm. If the thickness of the main conductor layer is less than 0.1 μm, the electric resistance tends to be large and the electric resistance required for the wiring conductor of the circuit board 4a tends not to be satisfied. Therefore, the main conductor layer tends to be easily separated from the diffusion preventing layer. Since Au is a noble metal and expensive, it is preferably formed as thin as possible in terms of cost reduction. Further, since Cu is easily oxidized, a protective layer made of Ni and Au may be coated thereon.

  In the case of the example shown in FIGS. 1 and 5, for example, the circuit board 4 a and the relay board 4 b are solder or gold (Au) -tin having a melting point of 200 to 400 ° C. on the surface of the ground conductor layer on the lower surface. (Sn) or other low melting point brazing material is printed on the brazing material paste using a screen printing method, a low melting point brazing material film is formed by photolithography, or a low melting point brazing material preform is disposed. And it fixes to the 1st base | substrate 1 by heating at the temperature of 200-400 degreeC. The electronic component 4 is fixed to the circuit board 4a bonded to the mounting portion 1a by brazing with a brazing material such as Au—Sn having a melting point of 200 to 400 ° C., and the electrode is bonded via the bonding wire 7. By connecting to the wiring conductor of the circuit board 4a and connecting the wiring conductor and the signal terminal 3a with the bonding wire 7, they are electrically connected to the signal terminal 3a. Further, for example, when the electronic component 4 is mounted on the circuit board 4a after the circuit board 4a is mounted on the base body 1, gold-tin (Au-Sn) alloy or gold-germanium ( An Au—Ge) alloy is used as a brazing material, and a brazing material of a tin-silver (Sn—Ag) alloy or a tin—silver—copper (Sn—Ag—Cu) alloy having a lower melting point is used for fixing the electronic component 4. Alternatively, an adhesive made of resin such as Ag epoxy that can be cured at a temperature lower than the melting point may be used. Further, after mounting the electronic component 4 on the circuit board 4a, the circuit board 4a may be mounted on the base body 1. In this case, contrary to the above, it is used when mounting the circuit board 4a on the base body 1. The melting point of the brazing material may be lowered. In any case, a brazing material paste is printed on the circuit board 4a or the mounting portion 1a of the base body 1 using a known screen printing method, a brazing material layer is formed by a photolithography method, A preform of a melting point brazing material may be placed.

  When a high-power LD element is mounted as the electronic component 4, the electronic component 4 is cooled more effectively so that the characteristics do not change due to a temperature change of the electronic component 4. As in the example shown in FIG. 6, the temperature control element 6 may be mounted on the mounting part 1a of the electronic component mounting package, and the electronic component 4 may be mounted thereon. The mounting method may be fixed by a low melting point brazing material as described above.

  The lid body 5 has an outer shape along the shape of the lid joint portion 1c in the outer peripheral area of the upper surface of the base body 1 in plan view, and covers a space that covers the electronic component 4 mounted on the mounting portion 1a on the upper surface of the base body 1. It has a shape. A window that transmits light may be provided at a portion facing the electronic component 4, or an optical fiber and an optical isolator for preventing return light may be joined instead of or in addition to the window.

  The lid 5 is made of a metal such as an Fe—Ni—Co alloy, an Fe—Ni alloy, or an Fe—Mn alloy, and is produced by subjecting these plate materials to a known metal working method such as press working or punching. . The lid 5 preferably has the same thermal expansion coefficient as that of the material of the substrate 1, and more preferably the same material as that of the substrate 1. When the lid 5 has a window, a flat or lens-shaped glass window member is bonded to a portion provided with a hole in the portion facing the electronic component 4 with a low-melting glass or the like.

  The lid body 5 is joined to the lid joint portion 1c of the base body 1 by welding such as seam welding or YAG laser welding or brazing with a brazing material such as an Au-Sn brazing material.

DESCRIPTION OF SYMBOLS 1 ... Base 1a ... Mounting part 1b ... Through-hole 1c ... Lid joint part 2 ... Sealing material 2a ... Recess 2b ... Projection part 3... Terminal 3a... Signal terminal 3b... DC terminal 4... Electronic component 4a ... Circuit board 4b ... Relay board 5. -Lid 6 ... Temperature control element 7 ... Bonding wire 8 ... Monitor PD
9: Reflector
10 ... Temperature monitor element

Claims (3)

A base including an upper surface and a lower surface, the electronic component mounting portion provided on the upper surface, and a through hole provided from the upper surface to the lower surface;
A sealing material filled in the through hole;
The electronic device is fixed to the base body through the sealing material, and has an upper end projecting upward from the upper surface of the base body and a lower end projecting downward from the lower surface of the base body. And a terminal to which the component is electrically connected,
The electronic component mounting package, wherein the sealing material has a recess formed so as to surround the terminal.   The electronic component mounting package according to claim 1, wherein the recess is formed apart from the terminal. The electronic component mounting package according to claim 1 or 2,
An electronic component mounted on the mounting portion of the electronic component mounting package;
An electronic apparatus comprising: a lid body joined to the upper surface of the base so as to cover the electronic component and the through hole.

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