JP2013157492A - Package for housing element and packaging structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a package for housing an element which is excellent in sealability and a packaging structure.SOLUTION: A package for housing an element 1 includes: a metal plate 3 which is a rectangular plate member and has cutout parts U located at positions that are symmetric relative to an axis L arranged perpendicular to one side on the one side in a plane view; a ceramic input/output terminal 4 provided on the metal plate 3 so as to be arranged along the one side and cover the pair of cutout parts U; and a frame body 5 provided along an outer periphery of the metal plate 3 so as to continue from an area on the metal plate 3 to an area on the ceramic input/output terminal 4.

Description

  The present invention relates to an element storage package in which an element can be mounted, and a mounting structure in which the element is mounted.

  In recent years, along with miniaturization of devices, a small device housing package capable of mounting an element such as an IC, a light emitting diode, a piezoelectric element, or a crystal resonator has been developed.

  In addition, an optical semiconductor package capable of mounting an optical semiconductor element such as a laser diode or a photodiode has been proposed (for example, see Patent Document 1).

  The package for optical semiconductors proposed in Patent Document 1 includes a mounting base made of a rectangular metal material on which an element is placed, a ceramic terminal member to which metallized wiring is attached, and a seal made of a metal material. And a ring.

JP 11-17041 A

  In the package for optical semiconductors proposed in Patent Document 1, the ceramic terminal member is removed from the mounting base and the seal ring due to the difference in thermal expansion coefficient between the ceramic terminal member and the mounting base. There is a possibility that the ceramic terminal member may be destroyed because the thermal stress cannot be absorbed. Then, the sealing performance of the package is not maintained, and as a result, the electrical characteristics of the elements placed in the package are deteriorated, resulting in a package failure.

  An object of the present invention is to provide an element storage package and a mounting structure excellent in sealing performance.

  An element storage package according to an embodiment of the present invention is a rectangular plate member, and has a notch at each of positions symmetrical with respect to an axis orthogonal to the one side when viewed from above. A metal plate, a ceramic input / output terminal provided on the metal plate so as to cover the pair of notches along the one side, and the ceramic input / output terminal from above the metal plate along an outer periphery of the metal plate And a frame body provided continuously over the top.

  The present invention can provide an element storage package and a mounting structure excellent in sealing performance.

It is an outline perspective view of a mounting structure concerning one embodiment of the present invention. It is a top view of the mounting structure concerning one embodiment of the present invention. It is a bottom view of the mounting structure concerning one embodiment of the present invention. It is a disassembled perspective view of the package for element storage which concerns on one Embodiment of this invention. It is a general | schematic perspective view of the input-output terminal which concerns on one Embodiment of this invention. It is a general-view perspective view of the frame concerning one embodiment of the present invention. It is a general-view perspective view of the metal plate which concerns on one Embodiment of this invention. It is a top view of the metal plate which concerns on one Embodiment of this invention.

  Hereinafter, an element storage package according to an embodiment of the present invention will be described with reference to the drawings.

<Configuration of mounting structure>
FIG. 1 is a schematic perspective view showing a mounting structure according to an embodiment of the present invention. FIG. 2 is a top view of the mounting structure shown in FIG. FIG. 3 is a bottom view of the mounting structure shown in FIG. FIG. 4 is an exploded perspective view of the element storage package 2 with the terminals and elements removed from the mounting structure. FIG. 5 is a schematic perspective view of the input / output terminals. FIG. 6 is a schematic perspective view of the frame. FIG. 7 is a schematic perspective view of a metal plate. FIG. 8 is a plan view of the metal plate.

  The element storage package 1 includes, for example, an active element such as a semiconductor element, a transistor, a diode, or a thyristor, or an element 2 that includes a passive element such as a resistor, a capacitor, a solar cell, a piezoelectric element, a crystal resonator, or a ceramic oscillator. It is used for mounting.

  The element storage package 1 is suitable for mounting and functioning an element corresponding to high withstand voltage, large current, or high speed and high frequency, and mounts a semiconductor element as an example of the element. The mounting structure is obtained by mounting a semiconductor element as an example of the element 2 on the element housing package 1.

  The element storage package 1 is a rectangular plate member, and a metal plate 3 having a notch U at each of left and right symmetrical positions with respect to an axis L orthogonal to one side when viewed from above, and a metal A ceramic input / output terminal 4 provided on the plate 3 so as to cover the pair of notches U along one side, and continuously from the metal plate 3 to the ceramic input / output terminal 4 along the outer periphery of the metal plate 3. And a provided frame 5.

The metal plate 3 is a member formed in a square shape when seen in a plan view, and a pair of notches U are formed on one side. The metal plate 3 is made of, for example, a metal material such as copper, iron, tungsten, molybdenum, nickel, or cobalt, or an alloy containing these metal materials. The metal plate 3 has good thermal conductivity, and the thermal conductivity of the metal plate 3 is set to 15 W / (m · K) or more and 450 W / (m · K) or less, for example. The thermal expansion coefficient of the metal plate 3 is set to, for example, 3 × 10 ⁻⁶ / K or more and 28 × 10 ⁻⁶ / K or less.

  Further, the metal plate 3 is manufactured in a predetermined shape by using a conventionally known metal working method such as rolling or punching for an ingot obtained by casting and solidifying a molten metal material into a mold. . Note that the length of one side of the metal plate 3 when viewed in plan is set to, for example, 5 mm or more and 50 mm or less. Moreover, the thickness of the up-down direction of the metal plate 3 is set to 0.3 mm or more and 5 mm or less, for example.

  Further, a metal layer such as nickel or gold is formed on the surface of the metal plate 3 by using an electroplating method or an electroless plating method in order to prevent oxidative corrosion. The thickness of the metal layer is set to, for example, 0.5 μm or more and 9 μm or less.

The frame 5 is a member that is connected along the outer periphery of the metal plate 3 and protects the element 2 from the outside. The frame body 5 has a shape in which a part of a frame shape formed in a quadrangular shape is cut out in plan view. Further, the frame body 5 is provided with the ceramic input / output terminal 4 at the cut-off portion C. Further, the frame body 5 is provided with a through hole H at a location facing the cut location C. The frame 5 is brazed to the metal plate 3 via a brazing material.

The frame 5 is made of, for example, a metal material such as copper, iron, tungsten, molybdenum, nickel, or cobalt, or an alloy containing these metal materials. The frame body 5 has a function of efficiently radiating heat generated from the element 2 in the frame body 5 to the outside of the frame body 5. The thermal conductivity of the frame 5 is set to, for example, 15 W / (m · K) or more and 450 W / (m · K) or less. The thermal expansion coefficient of the frame 5 is set to, for example, 3 × 10 ⁻⁶ / K or more and 28 × 10 ⁻⁶ / K or less.

  Further, the frame 5 has a size that can be accommodated in the metal plate 3 when viewed in plan, and the length of one side is set to, for example, 5 mm or more and 50 mm or less. Moreover, the thickness of the up-down direction except the location C where the frame 5 is cut is set to, for example, 1 mm or more and 10 mm or less. In addition, the upper and lower thicknesses including the cut portion C of the frame body 5 are set to, for example, 5 mm or more and 20 mm or less. Moreover, the thickness of the frame when the frame body 5 is viewed in plan is set to, for example, 0.5 mm or more and 3 mm or less.

  A ceramic input / output terminal 4 is provided at a location C where the frame 5 is cut. Further, a light transmissive member is provided at a portion where the through hole H of the frame body 5 is formed in order to pass light transmitted from an optical fiber provided outside to the inside of the frame body 5. In the through hole H, for example, a holding member capable of fitting a light transmissive member such as a lens, plastic, or glass is provided. The holding member can hold the optical fiber with the tip of the optical fiber approaching from the outside of the frame 5 to the vicinity of the light transmitting member.

  The ceramic input / output terminal 4 is a member provided at a location C where the frame 5 is cut. The ceramic input / output terminal 4 is provided on the rectangular flat plate portion 43, the first metal layer 41 formed on the flat plate portion 43, the standing wall portion 44 provided on the flat plate portion 43, and the standing wall portion 44. And the second metal layer 42. The first metal layer 41 is a base for connecting the terminals 6, and the second metal layer 42 is a base for connecting the frame 5. The flat plate portion 43 is a member formed in a square shape when viewed from above. Further, the standing wall portion 44 is a member having a shape obtained by removing one side from the frame shape when seen in a plan view.

The flat plate portion 43 and the standing wall portion 44 are insulating materials, for example, an aluminum oxide sintered body, a mullite sintered body, a silicon carbide sintered body, an aluminum nitride sintered body, and a silicon nitride sintered body. Or it consists of ceramic materials, such as glass ceramics. The first metal layer 41 and the second metal layer 42 are made of a refractory metal material such as tungsten, molybdenum, or manganese. In the ceramic input / output terminal 4, the thermal expansion coefficient of the flat plate portion 43 or the standing wall portion 44 made of a ceramic material is set to, for example, 3 × 10 ⁻⁶ / K or more and 8 × 10 ⁻⁶ / K or less. .

  Here, a manufacturing method of the ceramic input / output terminal 4 will be described. On the uncured flat plate portion 43 before firing, a plurality of first metal layers 41 are formed along one side of the flat plate portion 43 using, for example, a thin film forming technique such as vapor deposition, screen printing, or sputtering. . Moreover, the 2nd metal layer 42 is formed in the upper surface of the standing wall part 44 before baking using a thin film formation technique. And the uncured standing wall part 44 before baking is crimped | bonded on the flat plate part 43 in which the 1st metal layer 41 was formed, and both are baked simultaneously. In this way, the ceramic input / output terminal 4 can be manufactured.

In the ceramic input / output terminal 4 after firing, the flat plate portion 43 and the standing wall portion 44 are integrated. When the ceramic input / output terminal 4 is viewed in plan, the first metal layer 41 appears to be divided into two by the standing wall portion 44, but each first metal layer 41 is continuous immediately below the standing wall portion 44. . Therefore, when the ceramic input / output terminal 4 is viewed in plan, the first metal layer 41 is provided so as to extend to the inside and outside surrounded by the frame body 5. As a result, the element 2 in the frame 5 and an external electric device outside the frame 5 can be electrically connected via the first metal layer 41.

  The length of one side when the flat plate portion 43 is viewed in plan is set to, for example, 3 mm or more and 50 mm or less. The thickness of the flat plate portion 43 in the vertical direction is set to, for example, 0.3 mm or more and 5 mm or less. Moreover, the length of one side when the standing wall portion 44 is viewed in plan is set to, for example, 1 mm or more and 50 mm or less. The vertical wall thickness of the upright wall 44 is set to, for example, not less than 0.3 mm and not more than 5 mm. The thickness of the frame when the standing wall portion 44 is viewed in plan is set to, for example, 0.5 mm or more and 5 mm or less. The length in the vertical direction of the ceramic input / output terminal 4 matches the length in the vertical direction of the portion C where the frame 5 is cut.

  The terminal 6 is a member for electrically connecting to an external electronic device or the like. The terminal 6 is connected to the first metal layer 41 via a brazing material. Then, the first metal layer 41 and the terminal 6 are electrically connected. Further, by providing the adjacent first metal layers 41 with a space therebetween, the adjacent first metal layers 41 are electrically insulated from each other and electromagnetic coupling is suppressed. And by providing each terminal 6 in each 1st metal layer 41, while adjoining terminal 6 is electrically insulated, electromagnetic coupling is suppressed.

  As shown in FIG. 2, the mounting structure can be manufactured by mounting the element 2 in the element housing package 1. Note that the element 2 is electrically connected to the first metal layer 41 extending to the region surrounded by the frame body 5. Furthermore, an optical fiber is fixed to a holding member or the like provided in the through hole H of the element housing package 1, and a signal from the optical fiber can be input / output into the element housing package 1 through the light transmitting member. it can.

  Here, the notch U of the metal plate 3 will be described. As shown in FIG. 8, the notch U is formed at each of the left and right symmetrical positions around an axis L perpendicular to the one side when viewed in plan on one side of the rectangular plate member.

  The notch U is formed in a substantially rectangular outer shape. As shown in FIG. 8, the size of the notch U is, for example, 1 mm to 20 mm in length from the cut side, and the length in the direction along the cut side is, for example, It is set to 1 mm or more and 10 mm or less. Moreover, the length of the notch U in the vertical direction is set to, for example, 0.3 mm or more and 5 mm or less.

  Further, the notch U may be formed up to a position where the length from one side of the cut overlaps with the frame 5 when viewed in plan. As a result, the notch U efficiently radiates heat generated from the element 2 to the external circuit board through the metal plate 3 without being insulated by the notch U, and the metal plate 3 and the ceramic input / output terminal 4. The stress caused by the difference in thermal expansion coefficient between the frame body 5 and the frame body 5 can be relieved at the notch portion U. When the notch U is disposed inside the frame 5 in plan view, the notch U is formed from the element 2 through the metal plate 3 to the external circuit board by a heat insulating layer formed by the cavity. Heat dissipation is reduced. Further, when the cutout U is disposed outside the frame 5 in plan view, the notch U is concentrated in a portion where the metal plate 5, the ceramic input / output terminal 4 and the frame 5 overlap in plan view. The stress generated by the difference in expansion coefficient is not transmitted to the notch U, and the stress cannot be relieved by the notch U.

Since the notches U are formed symmetrically on the metal plate 3, heat is applied to the metal plate 3, the metal plate 3 attempts to undergo thermal expansion, or is cooled after the heat is applied to the metal plate 3. Even if the metal plate 3 tries to cause thermal contraction, the metal plate 3 does not cause thermal expansion or contraction at the notch U of the metal plate 3 and is further divided by the notch U. The thermal stress is relaxed by the convex portions of the metal plate 3. That is, since the metal plate 3 is reduced in volume by the notch U, it is possible to suppress the thermal stress caused by the volume shrinkage, and the stress is caused by the deformation in the convex portion of the metal plate 3 formed between the notches U. Alleviated. Therefore, for the ceramic input / output terminal 4 provided on the notch U of the metal plate 3, the metal plate 3, the ceramic input / output terminal 4, and the frame body 5 are joined in the manufacturing process of the element housing package 1. The thermal stress applied from the metal plate 3 when the brazing material is melted and then cooled can be alleviated, and the ceramic input / output terminal 4 and the metal plate can be reduced depending on the difference in thermal expansion coefficient between the metal plate 3 and the ceramic input / output terminal 4. 3 can be prevented from being cracked in the brazing material joining the ceramic input / output terminal 4 and the frame body 5. As a result, the sealing properties of the element storage package 1 and the mounting structure can be improved.

  Further, by providing a pair of notches U on one side of the metal plate 3 and arranging the ceramic input / output terminals 4 so as to straddle both the notches U, the stress applied to the ceramic input / output terminals 4 from the metal plate 3 is increased. It can be effectively suppressed. If the ceramic input / output terminal 4 is not formed so as to straddle both of the pair of notches U formed on one side of the metal plate 3, the ceramic input / output terminal 4 is not joined to the part to be joined. The deformation of the metal plate 3 varies depending on the part, and an uneven deformation or distortion occurs on the lower surface of the metal plate 3. As a result, the mounting structure composed of the element storage package 1 has a reduced mountability with the external circuit board, and the heat dissipation from the element storage package 1 to the external circuit board is significantly decreased. Further, by providing the notches U symmetrically with respect to the axis L orthogonal to one side of the metal plate 3, it is possible to reduce the distortion of the metal plate 3 due to heat. If the notches U are not formed symmetrically on the metal plate 3, the metal input / output terminals 4 and the frame 5 provided on the metal plate 3 are deformed by the metal plate 3 being biased and deformed. Cracks may occur in the brazing material that joins the ceramic input / output terminals 4 and the metal plate 3 to the ceramic input / output terminals 4 and the frame body 5 due to peeling from the plate 3 or due to locally concentrated thermal stress. There is an increased possibility that the mountability on the external circuit board will be reduced. Therefore, by forming the notches U symmetrically with respect to the axis L, the metal plate 3 can be prevented from being distorted, and the sealing performance of the element housing package 1 and the mounting structure is maintained well. In addition, the mountability of the mounting structure to the external circuit board can be improved.

  In addition, the notch U can store an excess brazing material when joining the metal plate 3, the frame body 5, and the ceramic input / output terminal 4, and between the ceramic input / output terminal 4 and the notch U. Since the meniscus can be formed, it is possible to suppress the variation in the thickness of the brazing material joining the metal plate 3, the frame 5, and the ceramic input / output terminal 4, and between the metal plate 3 and the ceramic input / output terminal 4. Bondability can be improved.

  When the axis L passes through the midpoint of one side where the notch U of the metal plate 3 is provided, the notch U may be arranged so as not to overlap the axis L. By doing so, a pair of notches U in which the axis L is line-symmetric can be provided on one side of the metal plate 3.

  Further, the four corners where the notch U is cut will be described. Of the four corners cut out of the notch U, two corners located on the center side of the metal plate 3 are curved, and the curvature thereof is set to 0.1 or more and 1 or less, for example. Of the four corners cut out of the notch U, two corners located on one side of the metal plate 3 are also curved, and the curvature thereof is set to, for example, 0.2 or more and 2 or less. .

By forming the four corners of the notch U to be curved, it is possible to alleviate the stress caused by the thermal expansion of the metal plate 3 concentrated at the four corners of the notch U from being concentrated at one corner of the four corners. In other words, the stress can be dispersed by the curved surfaces formed at the four corners of the notch U, and the occurrence of cracks at the four corners of the notch U can be suppressed. As a result, the gap between the ceramic input / output terminal 4 provided on the notch U and the metal plate 3 can be made difficult to occur, and the ceramic input / output terminal starting from the stress generated at the four corners of the notch U. 4 and the metal plate 3, the ceramic input / output terminal 4 and the frame 5 can be prevented from cracking, and the sealing property of the element storage package and the mounting structure can be improved. it can.

  As shown in FIG. 3, the end of one side of the metal plate 3 provided with the notch U is positioned so as to be located inside the ceramic input / output terminal 4 in plan view. That is, the ceramic input / output terminal 4 is arranged such that an end portion located on one side of the metal plate 3 provided with the notch U in plan view protrudes outside the metal plate 3. Then, by reducing the contact area between the lower surface of the ceramic input / output terminal 4 and the upper surface of the metal plate 3, the metal plate 3 and the ceramic input / output terminal 4 are added to the ceramic input / output terminal 4 from the metal plate 3. Thermal stress caused by the difference in thermal expansion coefficient can be reduced, the metal plate 3 is warped or distorted, the ceramic input / output terminal 4 is broken, the metal plate 3 and the ceramic input / output terminal 4, the frame 5. It is possible to reduce the possibility of cracks occurring in the brazing material joining the two.

  According to the present embodiment, a pair of notches U are provided on one side of the metal plate 3 and the ceramic input / output terminals 4 are provided on the metal plate 3 so as to cover the pair of notches. 4, the stress applied to the brazing material joining the metal plate 3, the ceramic input / output terminal 4 and the frame 5 can be relaxed, and the ceramic input / output terminal 4 can be peeled off from the metal plate 3 or the ceramic input / output terminal 4 can be removed. It is possible to suppress the occurrence of cracks in the brazing material that joins the ceramic input / output terminal 4 and the metal plate 3 to the ceramic input / output terminal 4 and the frame 5, and to prevent warping and distortion of the metal plate 3. Can be suppressed. As a result, it is possible to provide the element housing package 1 and the mounting structure that are excellent in sealing performance and mountability.

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

<Method for manufacturing mounting structure>
Here, a method for manufacturing the mounting structure shown in FIG. 1 or 2 will be described. First, each of the metal plate 3, the ceramic input / output terminal 4, and the frame 5 is prepared.

  Each of the metal plate 3 and the frame 5 is manufactured in a predetermined shape by using a metal processing method on a solidified ingot obtained by casting a molten metal material into a mold.

  For the ceramic input / output terminal 4, a ceramic green sheet that becomes the flat plate portion 43 and a ceramic green sheet that is die-cut so that a portion corresponding to the standing wall portion 44 remains are prepared. Next, the 1st metal layer 41 which consists of a metal paste which apply | coated the organic solvent containing molybdenum or manganese to the ceramic green sheet used as the flat plate part 43 using the screen printing method, for example is formed. The ceramic input / output terminal 4 is formed by laminating and sintering a ceramic green sheet in which the standing wall portion 44 is formed on the ceramic green sheet to be the flat plate portion 43 and cutting the ceramic green sheet into a desired shape. Is done. Furthermore, a metal layer is formed on the surface of the ceramic input / output terminal 4 which becomes a joint surface with the second metal layer 42 and the frame body 5 by screen printing. In this way, the ceramic input / output terminal 4 can be manufactured. Further, the prepared frame 5 is connected to the through hole H of the frame 5 by fitting a holding member mounted with a light transmissive member through a brazing material.

Next, each of the prepared metal plate 3, ceramic input / output terminal 4, and frame 5 is connected via a brazing material. Specifically, the ceramic input / output terminal 4 is connected to the notch U of the metal plate 3 through a brazing material. At this time, the frame body 5 has the frame body 5, the metal plate 3, and the ceramic input / output terminal 4 in a state where a brazing material separated into pieces is arranged in advance at a location where the frame body 5 and the ceramic input / output terminal 4 are connected. It joins by heating, making a brazing filler material spread on each joining surface, and cooling. In this way, the element storage package 1 can be manufactured. Furthermore, the mounting structure can be manufactured by mounting the element 2 on the manufactured element storage package 1 via solder and covering the element storage package with a lid.

DESCRIPTION OF SYMBOLS 1 Element storage package 2 Element 3 Metal plate 4 Ceramic input / output terminal 41 1st metal layer 42 2nd metal layer 43 Flat plate part 44 Standing wall part 5 Frame body 6 Terminal U Notch H Through-hole L Axis

Claims (4)

A rectangular plate member, and a metal plate having a notch at each of the positions symmetrical with respect to an axis orthogonal to the one side in one side when viewed in plan,
A ceramic input / output terminal provided on the metal plate so as to cover the pair of notches along the one side;
And a frame body provided continuously from the metal plate to the ceramic input / output terminal along the outer periphery of the metal plate. The device storage package according to claim 1,
A part of the ceramic input / output terminal protrudes outside the one side where the notch is provided in a plan view. The element storage package according to claim 1 or 2,
The element housing package, wherein the shaft passes through a midpoint of the one side.   An element storage package according to any one of claims 1 to 3, and an element mounted on the element storage package and electrically connected to the ceramic input / output terminal. Implementation structure to be

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