JP2011119634A - Package for electronic component mounting, and electronic device using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a package for electronic component mounting that has excellent transmission characteristics of high-frequency signals, and to provide an electronic device that excellently operates at high frequencies. <P>SOLUTION: The package for electronic component mounting includes a signal terminal 3 fixed penetrating a sealing material 2 filling a through hole 1a of a base 1 made of metal, and a wiring board 4 having a signal line conductor 4a on one principal surface and mounted on a mounting surface 1b parallel to a length direction of the through hole 1a of the base 1, an end of the signal terminal 3 being connected to the signal line conductor 4a with a brazing material 5. A thickness of the wiring board 4 is substantially equal to the distance between the signal terminal 3 and an inner surface of the through hole 1a, one end of the signal line conductor 4a of the wiring board 4 is formed up to an end of the wiring board 4 on the side of the through hole 1a, and a capacitive conductor 4b which extends in a width direction of the signal line conductor 4a is connected to the one end of the signal line conductor 4a. A ground nearby a conversion portion for conversion from a coaxial structure to a microstrip structure is reinforced to suppress deviation in characteristic impedance. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

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

  In recent years, demand for high-speed communication at a transmission distance of 40 km or less has increased rapidly, and attention has been paid to speeding-up of electronic devices such as semiconductor devices that receive and transmit optical signals using optical communication devices. The optical output of an electronic device typified by such a semiconductor device is about 0.2 to 0.5 mW, and the driving power of a semiconductor element used as an electronic component is about 5 mW. However, in a semiconductor device having a higher output, the optical output has become a level of 1 mW, and the driving power of the semiconductor element is required to be 10 mW or more. Furthermore, although the transmission speed of the conventional semiconductor device was about 2.5 to 10 Gbps (Giga bit per second), in recent years, semiconductor elements corresponding to 25 to 40 Gbps have been developed, and the output of the semiconductor device is higher. To increase the speed.

  A conventional electronic device in which an electronic component including an optical semiconductor element such as an LD (Laser Diode) or a PD (Photo Diode) is mounted on an electronic component mounting package is an electronic component mounting package. The signal terminal and the terminal of the electronic component are electrically connected via a bonding wire. Since the inductance of the bonding wire is large, impedance matching cannot be achieved and transmission loss of high-frequency signals is large.

  On the other hand, as shown in FIG. 8, the upper end of the signal terminal 13 fixed through the sealing material 12 filled in the through hole 11a formed in the disk-shaped base 11 made of metal. The electronic component mounting package that reduces the transmission loss of the high frequency signal is used by connecting the signal line conductor 14a of the wiring board 14 joined to the mounting surface 11b of the base body 11 with the brazing material 15 Has been. The electronic component 16 is mounted on the mounting surface 11b of the electronic component mounting package via the wiring board 14, and the signal terminal 13 and the terminal of the electronic component 16 are electrically connected via the signal line conductor 14a. A lid (not shown) is joined to the outer peripheral region of the upper surface of the upper cover so as to cover the electronic component 16 and hermetically sealed. (For example, see Patent Document 1).

  Even if the signal terminal 13 and the signal line conductor 14a alone are impedance matched to a certain characteristic impedance such as 25Ω or 50Ω, for example, the signal terminal 13 and the signal line conductor are connected at the connection portion between the signal terminal 13 and the signal line conductor 14a. There is a problem that the characteristic impedance is deviated by increasing the thickness of the signal line conductor 14a by bonding the conductor 14a with a bonding material such as a brazing material. On the other hand, in the electronic component mounting package having the structure in which the signal terminal and the wiring board are similarly connected by the brazing material, the thickness of the connection portion of the signal terminal with the signal line conductor is 10 to 50% of the remaining portion. Thus, it has been proposed to reduce the impedance gap (see, for example, Patent Document 2).

JP 2000-353846 A JP 2002-319643 A

However, in recent years, transmission signals have become higher in frequency with the demand for higher transmission speed due to an increase in the amount of information to be transmitted. In particular, when a signal with a higher frequency of 30 GHz or higher is transmitted, There is a problem that the impedance gap cannot be made sufficiently small by reducing the thickness of the terminal. In other words, in the connection portion between the signal terminal 13 and the signal line conductor 14a, the coaxial structure is converted to the microstrip line structure. In the middle of this conversion, the ground becomes weak due to the discontinuity of the propagation mode. This is because there is a problem that a section in which electromagnetic waves are radiated or characteristic impedance increases is generated, and transmission characteristics of high-frequency signals are deteriorated.

  The present invention has been completed in view of the above problems, and an object of the present invention is to provide an electronic component mounting package with good high-frequency signal transmission characteristics and an electronic device with good high-frequency operation.

  The electronic component mounting package of the present invention is fixed by penetrating through a base body made of metal having a through hole and a mounting surface parallel to the length direction of the through hole, and a sealing material filled in the through hole. An electronic device comprising: a signal terminal; and a wiring board having a signal line conductor on one main surface, mounted on the mounting surface of the base, and having an end portion of the signal terminal connected to the signal line conductor by a brazing material In the component mounting package, the wiring board has a thickness that is approximately the same as the distance between the signal terminal and the inner surface of the through hole, and one end of the signal line conductor of the wiring board is connected to the wiring board. A capacitor conductor that is formed up to the end portion on the through-hole side and that extends in the width direction of the signal line conductor is connected to the one end of the signal line conductor.

  In the electronic component mounting package of the present invention, the width of the connection portion of the capacitive conductor to the signal line conductor is smaller than one-fourth of the wavelength of the signal transmitted through the signal line conductor. It is characterized by this.

  In the electronic component mounting package of the present invention, in each of the above-described configurations, the end of the signal terminal is connected to overlap with the signal line conductor, and the end of the signal terminal overlaps with the signal line conductor Is not more than the width of the connecting portion of the capacitive conductor to the signal line conductor.

  In the electronic component mounting package of the present invention, in each of the above-described configurations, the length of the capacitive conductor from the connection portion with the signal line conductor is ¼ of the wavelength of the signal transmitted through the signal line conductor. It is characterized by being smaller than.

  The electronic component mounting package of the present invention is characterized in that, in each of the above configurations, the signal line conductor has a portion whose width gradually increases from one end to the other end side. .

  In the electronic component mounting package of the present invention, in the above configuration, the length of the portion where the width of the signal line conductor is gradually increased is a quarter of the wavelength of the signal transmitted through the signal line conductor. It is characterized by the above length.

  An electronic device according to the present invention is characterized in that an electronic component is mounted on the mounting surface or the wiring board of the electronic component mounting package of the present invention having the above-described configuration, and a lid is bonded to the base. It is.

According to the electronic component mounting package of the present invention, since the thickness of the wiring board is approximately the same as the distance between the signal terminal and the inner surface of the through hole, the electric field from the signal line conductor to the ground substrate is concentrated. Since the shortest distance and the distance from the signal terminal to the inner surface of the through hole, which is the ground, are approximately the same, the propagation mode in the course of conversion from the coaxial structure to the microstrip structure is suppressed, and electromagnetic waves are prevented from being radiated stably. In addition, since the capacitive conductor is connected to the end on the through hole side of the signal line conductor, the ground at the end of the signal line conductor is strengthened by capacitive coupling between the capacitive conductor and the base that is the ground, Since the characteristic impedance at the end of the signal line conductor is low, the characteristic impedance at the converter is near the converter from the coaxial structure to the microstrip structure. The increase is offset by a decrease in the characteristic impedance at the end of the signal line conductor close to the conversion unit, and an increase in the impedance near the conversion unit can be suppressed, and an electron with good high-frequency signal transmission characteristics. This is a component mounting package.

  According to the electronic component mounting package of the present invention, in the above configuration, when the width of the connecting portion of the capacitive conductor to the signal line conductor is smaller than one quarter of the wavelength of the signal transmitted through the signal line conductor, Since the distance between the part where the characteristic impedance is high and the part where the characteristic impedance is low is sufficiently small with respect to the wavelength of the signal to be transmitted, impedance matching by the capacitive conductor becomes more effective.

  According to the electronic component mounting package of the present invention, in each of the above-described configurations, the end of the signal terminal is connected to overlap with the signal line conductor, and the end of the signal terminal overlaps with the signal line conductor. When the length is equal to or less than the width of the connection portion of the capacitive conductor to the signal line conductor, the signal terminal overlaps in the portion where the capacitive conductor of the signal line conductor is not connected, so that the apparent appearance of the signal line conductor In the portion where the capacitive conductor of the signal line conductor is connected, it is possible to prevent the transmission characteristics from being deteriorated by increasing the parasitic capacitance due to the increase in the parasitic capacitance and thereby causing the impedance mismatch. Conversely, since the signal terminal functions in the same manner as the capacitive conductor, impedance matching becomes more effective.

  According to the electronic component mounting package of the present invention, in each of the above-described configurations, the length of the capacitive conductor from the connection portion with the signal line conductor is longer than a quarter of the wavelength of the signal transmitted through the signal line conductor. When the capacitance is small, the capacitive conductor does not function as a resonator like an open stub, so that it is possible to prevent the transmission characteristics from deteriorating due to signal resonance in the capacitive conductor.

  According to the electronic component mounting package of the present invention, in each of the above configurations, the signal line conductor has a high impedance when the signal line conductor has a portion whose width gradually increases from one end to the other end. Since the signal line conductor width gradually increases from one end of the signal line conductor on the conversion part side to the other end side having a predetermined characteristic impedance, the change in the characteristic impedance becomes gradual. Impedance matching can be achieved in FIG. 2, and better transmission characteristics can be obtained.

  According to the electronic component mounting package of the present invention, in the above-described configuration, the length of the portion where the width of the signal line conductor gradually increases is longer than ¼ of the wavelength of the signal transmitted through the signal line conductor. When this is the case, the distance at which the characteristic impedance changes gradually becomes sufficiently large with respect to the wavelength of the transmitted frequency, so that impedance matching by gradually increasing the width of the signal line conductor becomes more effective. Better transmission characteristics can be obtained.

  According to the electronic device of the present invention, the electronic component is mounted on the mounting surface or wiring board of the electronic component mounting package of the present invention having the above-described configuration, and the lid is joined to the base body. It becomes a good electronic device.

It is a perspective view which shows an example of embodiment of the electronic component mounting package of this invention. It is sectional drawing which shows the cross section in the AA of FIG. It is sectional drawing which shows the cross section in the BB line of FIG. (A)-(c) is a top view which shows an example of the principal part of the wiring board in the electronic component mounting package of this invention, respectively. (A)-(c) is a top view which shows an example of the wiring board in the electronic component mounting package of this invention, respectively. (A) is sectional drawing which shows the other example of embodiment of the electronic component mounting package of this invention, (b) is an enlarged view of the A section in (a). (A) is a perspective view which shows the other example of embodiment of the electronic component mounting package of this invention, (b) is sectional drawing in the AA of (a), (c) is a plane FIG. It is a perspective view which shows the example of the conventional electronic component mounting package.

  The electronic component mounting package and the electronic device of the present invention will be described in detail with reference to the accompanying drawings. 1 to 6, 1 is a base, 1a is a through hole, 1b is a mounting surface, 2 is a sealing material, 3 is a signal terminal, 4 is a wiring board, 4a is a signal line conductor, 4b is a capacitive conductor, A brazing material, 6 is an electronic component, 6a is a bonding wire, 7 is a ground terminal, and 8 is a lid.

  In the example shown in FIGS. 1 to 3 and FIG. 6, it is composed of a linear conductor fixed through a sealing material 2 filled in a through hole 1 a formed perpendicular to the main surface of the substrate 1. The signal terminal 3 is joined to the signal line conductor 4a formed on one main surface of the wiring board 4 joined to the mounting surface 1b formed perpendicularly to the base body 1 on the other main surface by the brazing material 5 in the present invention. An electronic component mounting package is basically constructed. Moreover, in the example shown in FIGS. 1-3 and FIG. 6, the electronic component 6 is mounted in the wiring board 4, and the state which connected the signal line conductor 4a and the electronic component 6 with the bonding wire 6a is shown. And the electronic device of this invention is comprised by joining the cover body 8 as shown with a broken line to the outer peripheral part of the base | substrate 1 like the example shown in FIG. 2 and FIG.

  The electronic component mounting package of the present invention includes a substrate 1 made of a metal having a through-hole 1a and a mounting surface 1b parallel to the length direction of the through-hole 1a, as in the examples shown in FIGS. The signal terminal 3 that is fixed through the sealing material 2 filled in the through hole 1a and the signal line conductor 4a on one main surface are mounted on the mounting surface 1b of the base 1, and the signal terminal 3 Of the electronic component mounting package including the wiring board 4 connected to the signal line conductor 4a by the brazing material 5. The wiring board 4 has a thickness between the signal terminal 3 and the inner surface of the through hole 1a. One end of the signal line conductor 4a of the wiring board 4 is formed to the end of the wiring board 4 on the through hole 1a side, and extends to one end of the signal line conductor 4a in the width direction of the signal line conductor 4a. Characterized in that a capacitive conductor 4b is connected A.

  According to such an electronic component mounting package, since the thickness of the wiring board 4 is approximately the same as the distance between the signal terminal 3 and the inner surface of the through hole 1a, from the signal line conductor 4a to the base body 1 that is the ground. The distance from the signal terminal 3 to the inner surface of the through-hole 1a, which is the ground, is approximately the same, so that the propagation mode in the course of conversion from the coaxial structure to the microstrip structure is stable and electromagnetic waves are obtained. Can be suppressed, and the signal line conductor 4a is connected to the end of the through hole 1a on the side of the through hole 1a, so that the capacitive conductor 4b and the grounded base 1 are capacitively coupled. Since the ground at the end of the signal line conductor 4a is strengthened and the characteristic impedance at the end of the signal line conductor 4a is reduced, the coaxial structure is changed to the microstrip structure. In the vicinity of the conversion unit, the increase in the characteristic impedance in the conversion unit is offset by the decrease in the characteristic impedance at the end of the signal line conductor 4a close to the conversion unit, thereby suppressing an increase in the impedance in the vicinity of the conversion unit. Therefore, the electronic component mounting package has good high frequency signal transmission characteristics.

The substrate 1 has a mounting surface 1b and a function of radiating heat generated by the mounted electronic component 6 to the outside of the package. For this reason, the base 1 is made of a metal having good thermal conductivity, and is close to the thermal expansion coefficient of the electronic component 6 or the ceramic wiring board 4 to be mounted or has a low cost. For example, Fe-Ni-Co An alloy such as an alloy or an Fe-Mn alloy or a metal such as pure iron is selected. More specifically, Fe99.6 mass% -Mn 0.4 mass% SPC (Steel
Plate Cold) material. For example, when the substrate 1 is made of an Fe—Mn alloy, the ingot (lumb) is manufactured in a predetermined shape by applying a known metal processing method such as rolling or punching, and the through-hole 1a is formed by drilling or molding. It is formed by punching. Further, the mounting surface 1b of the base body 1 can be formed by cutting or pressing.

The shape of the substrate 1 is usually a flat plate having a thickness of 0.5 to 2 mm, and the shape thereof is not particularly limited, but for example, a disk having a diameter of 3 to 10 mm and a circumference having a radius of 1.5 to 8 mm. For example, a semicircular plate with a part cut off, a square plate with a side of 3 to 15 mm, and the like. The thickness of the base body 1 may not be uniform. For example, if the thickness of the outer side of the base body 1 is increased, it becomes easy to closely attach a heat sink such as a housing for housing the electronic device. It is preferable because the generated heat is easily released to the outside through the substrate 1.

  In the example shown in FIGS. 1 to 3 and 6, one electronic component 6 is mounted on the base 1 having two through holes 1 a, but a plurality of electronic components 6 may be mounted, Depending on the number and the number of terminals of the electronic component 6, three or more through holes 1a for fixing the signal terminal 3 may be formed.

  The thickness of the substrate 1 is preferably 0.5 mm or more and 2 mm or less. When the thickness is less than 0.5 mm, the base 1 is bent depending on the joining conditions such as the joining temperature when joining the metallic lid 8 for protecting the electronic component 6 to the upper surface of the metallic base 1. It becomes easy to deform and the airtightness is likely to be lowered by the deformation. On the other hand, if the thickness exceeds 2 mm, the thickness of the electronic component mounting package or the electronic device becomes unnecessarily thick, and it is difficult to reduce the size.

  The surface of the substrate 1 has excellent corrosion resistance, excellent wettability with a brazing material for joining and fixing the electronic component 6, the wiring substrate 4 or the lid 8, and a Ni layer having a thickness of 0.5 to 9 μm. It is preferable to sequentially deposit an Au layer having a thickness of 0.5 to 5 μm by a plating method. As a result, it is possible to effectively prevent the base 1 from being oxidatively corroded and to satisfactorily braze the electronic component 6, the wiring board 4, or the lid 8 to the base 1.

  The signal terminal 3 is fixed so that one end protrudes from the upper surface of the base 1 so as to overlap with the signal line conductor 4 a and the other end protrudes from the lower surface of the base 1 by about 1 to 20 mm. For example, as in the example shown in FIGS. 1 to 3 and FIG. 6, one end of the signal terminal 3 and the electronic component 6 are electrically connected via the signal line conductor 4a and the bonding wire 6a, and the signal By electrically connecting the other end of the terminal 3 to an external electric circuit (not shown), the signal terminal 3 functions to transmit an input / output signal between the electronic component 6 and the external electric circuit.

  The sealing material 2 is made of an insulating inorganic material such as glass or ceramics, and has a function of securing an insulation interval between the signal terminal 3 and the base 1 and fixing the signal terminal 3 in the through hole 1 a of the base 1. Have. 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, when the sealing material 2 having a relative dielectric constant of 6.8 is used, the diameter of the through hole 1a is set to 0.75 mm when the outer diameter of the signal terminal 3 is 0.25 mm. can do. Further, when the sealing material 2 having a relative dielectric constant of 5 is used, when the outer diameter of the signal terminal 3 is 0.25 mm, the characteristic impedance is 25Ω by setting the diameter of the through hole 1a to 0.64 mm. By setting the diameter of the through hole 1a to 1.62 mm, the characteristic impedance can be set to 50Ω.

The signal terminal 3 is made of a metal such as Fe—Ni—Co alloy or Fe—Ni alloy. For example, when the signal terminal 3 is made of Fe—Ni—Co alloy, the ingot (lumb) is rolled or punched, By applying a known metal processing method such as cutting, a wire having a length of 1.5 to 22 mm and a diameter of 0.1 to 1 mm is manufactured. In order to reduce the size while performing matching with a higher characteristic impedance while ensuring the strength of the signal terminal 3, the diameter of the signal terminal 3 is preferably 0.15 to 0.25 mm. When the diameter of the signal terminal 3 is smaller than 0.15 mm, the signal terminal 3 is easily bent due to handling when the electronic component mounting package is mounted, and workability is easily lowered. On the other hand, if the diameter is larger than 0.25 mm, the diameter of the through hole 1a when impedance matching is increased with the diameter of the signal terminal 3, which is not suitable for downsizing of the product.

  To fix the signal terminal 3 through the sealing material 2 filled in the through-hole 1a, for example, when the sealing material 2 is made of glass, first, a known powder pressing method or extrusion molding method is used. Using this, glass powder is molded, the inside diameter is matched with the outside diameter of the signal terminal 3, a cylindrical shaped body is made with the outside diameter matched with the shape of the through hole 1a, and the hole in the shaped body of the sealing material 2 is produced. The signal terminal 3 is inserted into the mold, the molding pair is inserted into the mold, the glass is melted by heating to a predetermined temperature, and then cooled and solidified, whereby the signal terminal 3 is fixed and sealed. Stop material 2 is formed. Thus, the through hole 1a is hermetically sealed by the sealing material 2, and the signal terminal 3 is insulated and fixed from the base 1 by the sealing material 2 to form a coaxial line. Only the sealing material 2 matched to the shape of the through hole 1a is formed in advance, and this is inserted into the through hole 1a, and the signal terminal 3 is also inserted into the hole of the sealing material 2, and the sealing material 2 and the through hole are inserted. The inner surface of 1a and the outer surface of the signal terminal 3 may be joined at the same time.

  A ground terminal 7 is joined to the base 1. The ground terminal 7 is manufactured in the same manner as the signal terminal 3 and is joined to the lower surface of the base 1 using a brazing material or the like. In order to facilitate positioning and improve the bonding strength, a hole may be formed in advance on the lower surface of the substrate 1, and the ground terminal 7 may be inserted into the hole for bonding. By joining the ground terminal 7 to the base body 1 in this way, the base body 1 also functions as a ground conductor when the connection terminal 3 is connected to an external electric circuit.

The wiring substrate 4 is formed with a wiring conductor including the signal line conductor 4a on an insulating substrate made of a ceramic insulating material such as an aluminum oxide (alumina: Al ₂ O ₃ ) sintered body or an aluminum nitride (AlN) sintered body. It has been done. If the insulating substrate is made of, for example, an aluminum oxide sintered body, first, an organic solvent suitable for a raw material powder such as alumina (Al ₂ O ₃ ), silica (SiO ₂ ), calcia (CaO), magnesia (MgO), etc. , A solvent is added and mixed to form a slurry, which is formed into a sheet by a known doctor blade method, calendar 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.

The thickness of the wiring board 4 is approximately the same as the distance between the signal terminal 3 and the inner surface of the through hole 1a. More specifically, the thickness of the insulating substrate which is a dielectric of the wiring substrate 4 is the distance between the outer surface of the signal terminal 3 and the inner surface of the through hole 1a, that is, the sealing which is a dielectric between the signal terminal 3 and the through hole 1a. It is about the same as the thickness of the material 2. If the thickness of the insulating substrate of the wiring substrate 4 is ± 20% of the thickness of the sealing material 2, the propagation mode in the course of conversion from the coaxial structure to the microstrip structure is stably emitted as described above. Can be suppressed. In the example shown in FIG. 3, the mounting surface 1 b of the substrate 1 and the inner surface of the through hole 1 a are flush with each other, but the thickness of the insulating substrate of the wiring substrate 4 is ± 20% of the thickness of the sealing material 2. Since the thickness of the brazing material 5 between the signal terminal 3 and the signal line conductor 4a and the thickness of the bonding material between the wiring board 4 and the base body 1, the position of the mounting surface 1b with respect to the through hole 1a is penetrating. It may be inside or outside the hole 1a. Considering the ease of formation of the through hole 1a, the mounting surface 1b is preferably located outside the through hole 1a.

  For example, in the wiring substrate 4 of the example shown in FIG. 6, the wiring conductor is mounted on the upper surface of the insulating substrate with the signal line conductor 4 a for connecting the signal terminal 3 and the electronic component 6 and on the lower surface of the electronic component 6. A grounding conductor for connecting the ground electrode is formed, a mounting conductor for mounting on the base 1 is formed on the lower surface, and the grounding conductor and the mounting conductor are formed on the side surface of the insulating substrate. They are connected by connecting conductors formed or formed through the insulating substrate.

  The signal line conductor 4 a has a function of transmitting a signal from the signal terminal 3 to the electronic component 6. If the dielectric of the dielectric of the wiring board 4 is alumina having a relative dielectric constant of 9.5, the thickness is 0.2 mm, and the signal wiring 4 a has a microstrip structure, the characteristic impedance is obtained when the width of the signal line conductor 4 a is 0.64 mm. Becomes 25Ω.

  The signal line conductor 4a is formed in accordance with the electronic component 6 because the connection differs depending on the electronic component 6. The electronic component 6 and the signal line conductor 4a are connected by, for example, a bonding wire 6a. In order to reduce signal transmission loss by shortening the bonding wire 6a, for example, FIG. 2, FIG. 5 and FIG. It is preferable that the signal line conductor 4a is bent as in the example shown in FIG. 5 so that the connection position of the bonding wire 6a is as close as possible to the electronic component 6.

When the signal line conductor 4a is bent, it is bent stepwise so that the bending angle is larger than 90 °, as in the examples shown in FIGS. It is preferable to round the corners because the loss of high frequency due to reflection at the bent portion can be reduced. In the case of bending stepwise, it is preferable to set the bending angle to 120 ° or more because loss is reduced. Further, in the examples shown in FIGS. 2, 5, and 6, only the outer side of the bent portion is bent stepwise, but it is more likely that the inner side of the bent portion is bent stepwise and rounded in the same manner. preferable.

As described above, one end of the signal line conductor 4a is formed to the end of the wiring board 4 on the through hole 1a side, and the capacitor conductor 4b extending in the width direction of the signal line conductor 4a is connected to one end of the signal line conductor 4a. ing. It is preferable to shorten the portion between the coaxial structure and the microstrip structure and shorten the portion where the impedance is not matched. Specifically, the length of the portion of the signal terminal 3 that protrudes from the main surface of the base 1 and is connected to the signal line conductor 4a of the wiring board 4 is a quarter of the wavelength of the signal transmitted through the signal terminal 3. If it is shorter than 1, the transmission characteristics of high-frequency signals are good. In order to shorten this length, as shown in the example shown in FIG. 6B, the signal line conductor 4a is formed as far as the end of the wiring board 4, and the surface of the wiring board 4 through which the through hole 1a of the base 1 is opened. It is good to mount in contact with. At this time, when the length of the capacitive conductor 4b is long and the tip end side of the capacitive conductor 4b comes into contact with the base body 1 as a ground, as shown in the examples shown in FIGS. The line conductor 4a is preferably formed from the end of the wiring board 4 on the through hole 1a side to the inside by about 0.1 mm. Alternatively, as in the example shown in FIG. 6B, when the tip end side of the capacitive conductor 4b is formed about 0.1 mm inward from the end on the through hole 1a side of the wiring board 4, the transmission characteristics are further improved.

The width (W shown in FIG. 4) of the connection portion between the capacitive conductor 4b and the signal line conductor 4a is preferably smaller than a quarter of the wavelength of the signal transmitted through the signal line conductor 4a. By doing so, the distance between the part where the characteristic impedance is high (the conversion part from the coaxial structure to the microstrip structure) and the part where the characteristic impedance is low is sufficiently small with respect to the wavelength of the transmission frequency. Impedance matching by the capacitive conductor 4b becomes more effective.

  The length of the portion where the signal terminal 3 overlaps with the signal line conductor 4a (L3 shown in FIG. 6B) is preferably equal to or less than the width of the connection portion of the capacitive conductor 4b with the signal line conductor 4a. By doing in this way, in the part where the capacitive conductor 4b of the signal line conductor 4a is not connected, the signal terminal 3 overlaps and is connected to increase the apparent thickness of the signal line conductor 4a. It is possible to prevent the transmission characteristics from deteriorating due to an increase in capacity and an impedance mismatch. On the contrary, the signal terminal 3 functions in the same manner as the capacitive conductor 4b in the portion where the capacitive conductor 4b of the signal line conductor 4a is connected. Therefore, impedance matching is effective even with a smaller capacitive conductor 4b. It will be something.

  Moreover, it is preferable that the length (L1 shown in FIG. 4) from the connection part with the signal line conductor 4a of the capacity | capacitance conductor 4b is smaller than 1/4 of the wavelength of the signal which transmits the signal line conductor 4a. By doing so, since the capacitive conductor 4b does not function as a resonator like an open stub, it is possible to prevent deterioration of transmission characteristics due to signal resonance in the capacitive conductor 4b.

Specifically, when the transmission speed of the signal transmitted through the signal line conductor 4a is 25 Gbps, the frequency component is DC to 37.5 GHz in consideration of the triple harmonic component. In the signal line conductor 4a, In the case of alumina having a relative dielectric constant of 9.5 and a microstrip structure, the effective relative dielectric constant is about 7 or less, and the wavelength of the signal transmitted through the signal line conductor 4a is about 3 mm. The width W and the length L1 of the connecting portion with 4a are preferably 0.75 mm or less.

  The size of the capacitive conductor 4b is set according to the amount of capacitive coupling between the required capacitive conductor 4b and the base body 1 serving as the ground. If this capacitive coupling is large, the area of the capacitive conductor 4b may be increased, and the length and width thereof may be increased. However, for the reasons described above, the length L1 of the capacitive conductor 4b and the width W of the connecting portion are preferably small. Therefore, as shown in FIG. 4B and FIG. The area W of the signal line conductor 4a may be increased by reducing the width W of the connecting portion and increasing the width on the tip side.

  Further, in order to increase the area, the capacitive conductor 4b may be provided on both sides of the end portion of the signal line conductor 4a as in the examples shown in FIGS. In such a case, the length L1 from the connecting portion with the signal line conductor 4a may be different on both sides as in the example shown in FIG. As in the example shown in FIG. 5A, one side may be elongated according to the space for forming the capacitive conductor 4b around the signal line conductor 4a.

  Moreover, it is preferable that the signal line conductor 4a has a portion whose width gradually increases from one end to the other end side, as in the examples shown in FIGS. 5B and 5C. At one end of the signal line conductor 4a, the impedance is lowered by the capacitive conductor 4b, but the impedance is not perfectly matched in the vicinity of the conversion portion from the coaxial structure to the microstrip structure, that is, the impedance may be high. It is necessary to obtain impedance matching by narrowing the width at one end to match the high impedance and widening the width of the signal line conductor 4a toward the other end with a predetermined characteristic impedance. By increasing it, the change in characteristic impedance becomes gradual, so that impedance matching can be achieved particularly in the high frequency region, and better transmission characteristics can be obtained.

  At this time, when the length (L2 shown in FIG. 5) of the portion where the width of the signal line conductor 4a gradually increases is not less than ¼ of the wavelength of the signal transmitted through the signal line conductor 4a, Since the distance L2 at which the change in impedance becomes gradual becomes sufficiently large with respect to the wavelength of the transmission frequency, impedance matching by gradually increasing the width of the signal line conductor 4a becomes more effective and better. Transmission characteristics can be obtained.

  The portion where the width of the signal line conductor 4a gradually increases may be only at one end side of the signal line conductor 4a as in the example shown in FIG. 5C, or in the example shown in FIG. Thus, the whole area to the connection part with the electronic component 6 may be sufficient.

  The wiring conductor including the signal line conductor 4a can be formed by a well-known method of forming metal metallization by simultaneous firing with the insulating substrate, or after forming the insulating substrate, or by vapor deposition or photolithography after forming the insulating substrate. There is a method of forming. When the electronic device is small, the wiring board 4 mounted on the electronic device is further small, so that the wiring conductor is fine, and in order to increase the alignment accuracy between the wiring conductor and the signal terminal 3, vapor deposition or photo A method of forming by a lithography method is preferable. In this case, the main surface of the insulating substrate may be polished as necessary.

  Hereinafter, the case where the wiring conductor is formed by vapor deposition or photolithography will be described in detail. 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.

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 the thermal expansion coefficient is at least one of metals close to that of ceramics, such as a Cr) alloy and tantalum nitride (Ta ₂ N), and the thickness 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.

  From the viewpoint of preventing mutual diffusion between the adhesion metal layer and the main conductor layer, the diffusion prevention layer is platinum (Pt), palladium (Pd), rhodium (Rh), nickel (Ni), Ni—Cr alloy, Ti— It is preferably made of at least one metal having good thermal conductivity such as 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. 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.

  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 wiring board 4 tends not to be satisfied. If the thickness exceeds 5 μm, it is led by internal stress during film formation. There is a tendency that the body layer is easily peeled off from the diffusion preventing layer. Further, since Cu is easily oxidized, a protective layer made of Ni and Au may be coated thereon.

  The wiring board 4 produced in this way is joined to the mounting surface 1b of the base 1, and the tip of the signal terminal 3 and the signal line conductor 4a are connected by the brazing material 5 to provide the electronic component mounting package of the present invention. .

  Then, by mounting the electronic component 6 on the wiring substrate 4 and joining the lid 8 to the base body 1, the electronic device of the present invention as in the example shown in FIGS. 2, 3, and 6 is obtained. Since the wiring board 4 as described above is provided, the electronic device can be operated with high frequency.

  Examples of the electronic component 6 include optical semiconductor elements such as LD (laser diode) and PD (photodiode), semiconductor elements including semiconductor integrated circuit elements, piezoelectric elements such as crystal resonators and surface acoustic wave elements, and pressure sensor elements. , Capacitive elements, resistors and the like.

  The mounting of the electronic component 6 on the wiring substrate 4 or the mounting of the wiring substrate 4 on the electronic component mounting package may be performed by fixing with a conductive bonding material such as a brazing material or a conductive resin. For example, when the electronic component 6 is mounted on the wiring substrate 4 after mounting the wiring substrate 4 on the base body 1, a gold-tin (Au—Sn) alloy or gold-germanium (Au—) is used to fix the wiring substrate 4. A brazing material of Ge) alloy is used as a bonding material, and for fixing the electronic component 6, a tin-silver (Sn-Ag) alloy or a tin-silver-copper (Sn-Ag-Cu) alloy having a melting point lower than these is used. A brazing material or a resin adhesive such as Ag epoxy that can be cured at a temperature lower than the melting point may be used as the bonding material. In addition, after mounting the electronic component 6 on the wiring board 4, the wiring board 4 may be mounted on the base 1, and in that case, contrary to the above, it is used when mounting the wiring board 4 on the base 1. The melting point of the bonding material may be lowered. In any case, a paste of a bonding material is printed on the wiring board 4 or the mounting portion 1b of the base body 1 using a well-known screen printing method, a bonding material layer is formed by a photolithography method, What is necessary is just to mount the preform of the low melting-point brazing material used as a joining material.

  The lid body 8 has an outer shape along the outer peripheral region of the base body 1 and has a shape having a space that covers the electronic component 6 mounted on the mounting portion 1 b of the base body 1. A window that transmits light may be provided in a portion facing the electronic component 6, or an optical fiber and an optical isolator for preventing return light may be joined in place of or in addition to the window.

  The lid 8 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 processing method such as press working or punching. . The lid 8 preferably has the same thermal expansion coefficient as the material of the base 1, and more preferably the same as the material of the base 1. When the lid 8 has a window, a plate-like or lens-like glass window member is joined to a member provided with a hole in the portion facing the electronic component 6 with a low melting point glass or the like.

  The lid 8 is joined to the base body 1 by welding such as seam welding or YAG laser welding or by brazing with a brazing material such as an Au-Sn brazing material.

  The present invention is not limited to the above-described embodiments and examples, and various modifications can be made without departing from the scope of the present invention.

  For example, in the above example, an electronic component mounting package using a circular metal stem as shown in FIGS. 1 to 3 and 6 has been described as an example, but the electronic component mounting package of the present invention is shown in FIG. It may be a box-type electronic component mounting package as shown. FIG. 7A is a perspective view showing another example of the embodiment of the electronic component mounting package of the present invention, and FIG. 7B is a cross section showing a cross section taken along line AA of FIG. 7A. FIG. 7C is a plan view. Each code | symbol in FIG. 7 shows the site | part similar to FIGS.

The electronic component mounting package of the example shown in FIG. 7 is provided with a mounting surface 1b on the bottom surface of the box-shaped substrate 1, and has a through hole 1a that surrounds the bottom surface and is perpendicular to the mounting surface 1b. The wiring board 4 is mounted on the mounting surface 1b, and the signal terminal 3 is fixed by a sealing material 2 in a through hole 1a formed in the frame portion. The signal terminal 3 and the signal line conductor 4 a on one main surface of the wiring board 4 are electrically connected by a brazing material 5.

  In the case of the example shown in FIG. 7, a base 1 made of a metal ingot similar to the above using a known metal processing method such as rolling, punching, and cutting is formed into a flat plate with a joining material such as silver brazing. It is formed by joining. Further, the base body 1 may be manufactured by forming the frame portion integrally with the flat plate by, for example, a metal injection molding method or the like.

  The wiring board 4 in the case of the example shown in FIG. 7 is manufactured in the same manner as the wiring board 4 in the examples shown in FIGS. 1 to 3 and 6, but an electronic component 6 is provided on one main surface of the wiring board 1. Is not mounted, only the signal line conductor 4a is formed, and the signal line conductor 4a and the mounting conductor on the other main surface functioning as a ground conductor constitute a microstrip line.

  The electronic component 6 is mounted on the mounting surface 1b of the base 1, the terminal of the electronic component 6 and the signal line conductor 4a of the wiring board 4 are connected by the bonding wire 6a, and the lid body 8 is bonded to the upper surface of the frame portion. By doing so, the electronic device of the present invention is obtained. In this example, the electronic component 6 is directly mounted on the mounting surface 1 b of the base 1, which is to radiate the heat generated in the electronic component 6 to the outside through the mounting surface 1 b of the metal base 1. When the heat generation of the electronic component 6 is large, a Peltier element or the like may be mounted between the electronic component 6 (and the wiring board 4) and the mounting surface 1b to cool the electronic component 6.

DESCRIPTION OF SYMBOLS 1 ... Base 1a ... Through-hole 1b ... Mounting surface 2 ... Sealing material 3 ... Signal terminal 4 ... Wiring board 4a ... Signal line conductor 4b Capacitor conductor 5 Brazing material 6 Electronic component 6a Bonding wire 7 Grounding terminal 8 Lid

Claims (7)

A base body made of metal having a through hole and a mounting surface parallel to the length direction of the through hole, a signal terminal fixed through the sealing material filled in the through hole, and a signal line on one main surface An electronic component mounting package comprising a wiring board having a conductor, mounted on the mounting surface of the base, and having an end of the signal terminal connected to the signal line conductor by a brazing material, The substrate has a thickness approximately the same as the distance between the signal terminal and the inner surface of the through hole, and one end of the signal line conductor of the wiring substrate is formed to the end of the wiring substrate on the through hole side. An electronic component mounting package, wherein a capacitor conductor extending in a width direction of the signal line conductor is connected to the one end of the signal line conductor. 2. The electronic component mounting package according to claim 1, wherein a width of a connection portion between the capacitive conductor and the signal line conductor is smaller than a quarter of a wavelength of a signal transmitted through the signal line conductor. The end portion of the signal terminal is connected to overlap with the signal line conductor, and the length of the portion where the end portion of the signal terminal overlaps with the signal line conductor is the connection portion of the capacitive conductor with the signal line conductor. The electronic component mounting package according to claim 1, wherein the electronic component mounting package is equal to or less than the width of the electronic component mounting package. The length from the connection part with the said signal line conductor of the said capacity | capacitance conductor is smaller than 1/4 of the wavelength of the signal which transmits the said signal line conductor, The any one of Claim 1 thru | or 3 characterized by the above-mentioned. Package for mounting electronic components as described in Crab. 5. The electronic component mounting package according to claim 1, wherein the signal line conductor has a portion whose width gradually increases from one end to the other end side. 6. The length of the portion where the width of the signal line conductor is gradually increased is one quarter or more of the wavelength of a signal transmitted through the signal line conductor. Electronic component mounting package. An electronic device comprising an electronic component mounted on the mounting surface or the wiring board of the electronic component mounting package according to any one of claims 1 to 6, and a lid body bonded to the base. .

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