JP2006185953A - Package for containing electronic component and electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a package for containing an electronic component and an electronic device exhibiting excellent hermetic sealing properties and reliability in which an insulating substrate can be protected against cracking due to stress, e.g. thermal stress incident to thermal expansion/contraction at the time of bonding a lid. <P>SOLUTION: The package for containing an electronic component comprises an insulating substrate 101 having a recess 104 for containing the electronic component 107 in the upper surface and a cut 102 in the side face, a plurality of connection pads 106 formed in the recess 104 of the insulating substrate 101 and being connected with the electronic component 107 electrically, and a metallization layer 103 formed on the upper surface of the insulating substrate 101 to surround the recess 104 wherein the insulating substrate 101 has a protrusion 105 formed thick on the inside of the recess 104 at the side end of the cut 102. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electronic component storage package and an electronic device having a recess for accommodating an electronic component such as a crystal resonator or a semiconductor element on an upper surface of an insulating base, and in particular, a notch is provided on a side surface of the insulating base. The present invention relates to an electronic component storage package and an electronic device.

  2. Description of the Related Art Conventionally, an electronic component storage package for storing an electronic component such as a crystal resonator or a semiconductor element has an insulative base having a recess for accommodating the electronic component on the upper surface and a notch on the side surface, and a recess in the insulating base. And a plurality of connection pads electrically connected to the electronic component, and a metallization layer formed on the upper surface of the insulating base so as to surround the recess.

  As such an electronic component storage package, for example, a ceramic package made of an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, glass ceramics, or the like is used.

  2A and 2B are a top view and a side perspective view showing an example of a conventional electronic component storage package and an electronic device, respectively. As shown in FIG. 2, the conventional package includes an insulating base 201, a recess 204 that is formed on the upper surface of the insulating base 201 and accommodates an electronic component 207 such as a semiconductor element, and a connection pad 206 formed in the recess 204. It is equipped with.

  For example, the electronic component 207 is accommodated in the concave portion 204 of the insulating base 201, and the electrodes of the electronic component 207 are electrically connected to the connection pads 206 via an electrical connection means such as a bonding wire or solder. The electronic component 207 is sealed by attaching the lid 211 to the upper surface of the insulating base 201 and closing the recess 204.

  For attaching the lid 211 to the insulating base 201, a metallized layer 203 is formed on the upper surface of the insulating base 201 so as to surround the recess 204, and the lid 211 is joined to the metallized layer 203 by joining means such as brazing or welding. It is carried out by a method such as joining with. In some cases, the metal frame 208 is brazed to the metallized layer 203 and the lid is joined via the metal frame 208 by a welding method such as seam welding.

  Further, in such an electronic component storage package or an electronic device, a notch 202 is formed on the side surface of the insulating base 201.

  The notch 202 has, for example, a conductive layer 209 electrically connected to the connection pad 206 attached to the surface thereof, and the electronic component 207 connected to the connection pad 206 is electrically connected to an external electric circuit (not shown). A connecting portion is formed for connection.

The conductor layer 209 can also function as a connection terminal for rewriting the memory contents of the electronic component 207 (semiconductor element). In this case, if a crystal resonator (not shown) is mounted in the recess 204 above or below the semiconductor element 207, temperature compensation is accurately performed in accordance with the vibration characteristics of the crystal resonator, the use environment of the electronic device, and the like. Thus, a temperature compensated crystal oscillator capable of adjusting the function of the semiconductor element 207 can be provided.
JP 2001-274628 A

  However, in recent years, in the electronic component storage package and the electronic device, for example, the length of one side of the insulating base 201 has been reduced to 5 mm or less due to downsizing. Therefore, in order to efficiently accommodate the electronic component 207 to be accommodated with respect to the limited mounting area (planar area of the insulating base 201), it is necessary to narrow the width of the frame portion 210 surrounding the recess 204.

  In addition, as the functionality of electronic devices increases, the number of electronic components 207 accommodated in the recesses 204 increases, and the depth of the recesses 204 is increased in order to accommodate these electronic components 207 vertically without increasing the mounting area. It is also required to deepen the depth.

  Therefore, the frame portion 210 surrounding the recess 204 in the insulating base 201 has a narrow width and a high height.

  As described above, when the width of the frame portion 210 is narrowed and the height thereof is increased, the mechanical strength of the frame portion 210 is decreased, which is accompanied by thermal expansion and contraction when the lid body 211 is joined to the upper surface of the insulating base 201. There is a problem that cracks may occur in the insulating base 201 at a portion adjacent to the notch 202 where stress is likely to concentrate due to thermal stress.

  In addition, when the metallized layer 203 is formed on the upper surface of the insulating base 201 and the metal frame 208 is joined to the metallized layer 203 via a brazing material, the coefficient of thermal expansion between the metal frame 208 and the insulating base 201 is used. Since the thermal stress resulting from the difference occurs, there is a high possibility that the above-described cracks are generated in the insulating base 201 provided with the metal frame 208.

  The crack starts from a side end portion where stress is particularly concentrated in the notch portion 202, and the direction in which the stress generally acts toward the surface and end surface of the nearby insulating base 201 such as the upper surface of the frame portion 210. It has been confirmed by experiments that it proceeds along (lateral direction or diagonally upward direction).

  Further, since the bonding width of the frame portion 210 to the metal frame 208 is narrowed, the reliability of the bonding of the lid 211 is lowered, and there is a possibility that the inside of the recess 204 cannot be sealed with good airtightness.

  The present invention has been devised in view of such problems, and an object of the present invention is to provide a lid on the upper surface of the insulating base in a wiring board having a recess on the upper surface of the insulating base and a notch on the side surface. To provide an electronic component storage package and an electronic device that are excellent in hermetic sealing and reliability by reducing the possibility of cracks in an insulating substrate due to stress such as thermal stress accompanying thermal expansion and contraction during bonding. It is in.

  The electronic component storage package according to the present invention is formed in the concave portion of the insulating base, the insulating base having a concave portion for accommodating the electronic component on the upper surface, and a cutout portion on the side surface. A plurality of connection pads connected to each other, and a metallization layer formed on an upper surface of the insulating base so as to surround the concave, and the insulating base has a recess corresponding to an outer end of the notch. A protrusion is formed on the inner surface.

  In the electronic component storage package of the present invention, the width of the protruding portion is wider than the width of the notched portion.

  The electronic component storage package of the present invention is characterized in that the projecting portion is formed between the plurality of connection pads.

  An electronic device according to the present invention includes any one of the electronic component storage packages described above, the electronic component housed in the recess of the electronic component storage package and electrically connected to the plurality of connection pads, and the metallization. It has a metal frame joined to the layer and a lid joined to the metal frame.

  In the electronic component storage package of the present invention, the protrusion is formed on the inner side surface of the recess corresponding to the outer end of the notch, so that the side end of the notch, that is, the site that is likely to be the starting point of the crack. Thus, the mechanical strength of the frame portion surrounding the concave portion of the insulating base can be effectively reinforced. Accordingly, it is possible to prevent cracks from being generated in the insulating substrate due to stress such as thermal stress accompanying thermal expansion and contraction when the lid is bonded to the upper surface of the insulating substrate.

  In addition, the electronic component storage package of the present invention can further improve the mechanical strength of the insulating base that surrounds the recess more effectively because the width of the protruding portion is wider than the width of the notch. It can prevent more reliably that a crack generate | occur | produces.

  In the electronic component storage package according to the present invention, since the projecting portion is formed between the plurality of connection pads, the electronic component is electrically connected to the connection pads via an electrical connection means such as a bonding wire or solder. Therefore, the connection between the electronic component and the connection pad is not deteriorated due to the protruding portion obstructing the connection. Therefore, it is possible to provide an insulating base that is excellent in the reliability of hermetic sealing and excellent in mountability and connectivity in the recess of the electronic component.

  The electronic device of the present invention includes an electronic component storage package of the present invention, an electronic component that is housed in a recess of the electronic component storage package and is electrically connected to a plurality of connection pads, and a metal that is bonded to the metallization layer. By providing the frame and the lid bonded to the metal frame, the lid is firmly bonded to the insulating base via the metal frame, and the lid is attached to the metal frame on the upper surface of the insulating base. Provided is an electronic device excellent in hermetic sealing and reliability, in which cracks are effectively prevented from occurring in an insulating substrate due to stress such as stress accompanying thermal expansion and contraction when joining bodies. be able to.

  An electronic component storage package and an electronic device according to the present invention will be described with reference to the accompanying drawings. 1A and 1B are a plan view and a side perspective view, respectively, showing an example of an embodiment of an electronic component storage package and an electronic device according to the present invention.

  In the figure, reference numeral 101 denotes an insulating substrate, 102 denotes a notch, 103 denotes a metallized layer, 104 denotes a recess in which the electronic component 107 is accommodated, 105 denotes a protruding portion, and 106 denotes a connection pad to which the electronic component is connected.

  In this electronic component storage package, an electronic device is configured by housing the electronic component 107 in the recess 104 and sealing the electronic component 107 by means such as closing the opening of the recess 104 with the lid 111.

  The insulating base 101 is made of a ceramic or a resin such as an aluminum oxide sintered body (alumina ceramic), an aluminum nitride sintered body, a mullite sintered body, or a glass ceramic, and has a side length of about 3 to 20 mm. It has a rectangular parallelepiped shape with a thickness of about 1 to 5 mm.

  In addition, a concave portion 104 in which the electronic component 107 is accommodated is formed on the upper surface of the insulating base 101.

  If such an insulating substrate 101 is made of an aluminum oxide sintered body, it is manufactured as follows. First, an appropriate organic vanida, solvent, plasticizer, etc. are added to and mixed with raw material powders such as aluminum oxide, silicon oxide, magnesium oxide, calcium oxide, etc. to form a mud, which is a well-known doctor blade method or calendar roll method. Etc. to form a plurality of ceramic green sheets. After that, the ceramic green sheet is appropriately punched to form a square plate shape and a square frame shape, and the square frame shape is positioned so that the square plate shape is located in the lower layer. It is manufactured by stacking up and down so as to be positioned in the upper layer, forming a stacked body having a recess 104 on the upper surface, and firing the stacked body at a high temperature (about 1600 ° C.).

  A connection pad 106 to which the electronic component 107 is electrically connected is formed inside the recess 104. The electronic component 107 is, for example, a semiconductor element such as a semiconductor integrated circuit element or an optical semiconductor element, a piezoelectric element such as a crystal resonator or a surface acoustic wave element, a capacitor element, and the like. There are electrodes on the main surface.

  In this case, when an electrode is formed on the upper surface, it is exposed to the bottom surface of the recess 104 by, for example, a solder bump (not shown), and when an electrode is formed on the lower surface, for example, by a bonding wire such as a gold wire. The connection pad 106 is connected.

  The connection pad 106 is formed at a position suitable for electrical connection with the electronic component 107. For example, when the connection pad 106 is connected to the upper surface portion of the electronic component 107 via a bonding wire, the connection pad 106 is formed on the inner surface of the recess 104 at a height approximately equal to the thickness of the electronic component 107 from the bottom surface of the recess 104. A stepped portion is formed and formed on the upper surface of the stepped portion.

  The connection pad 106 is made of a metal material such as tungsten, molybdenum, manganese, copper, silver, and, for example, if made of tungsten, a conductive paste prepared by adding an organic solvent, a binder, etc. to tungsten powder and kneading, It is formed by printing a predetermined pattern on the surface of a green sheet to be the insulating substrate 101.

  The electronic component electrically connected to the connection pad 106 extends a part of the connection pad 106 to the side surface through the inside of the insulating base 101, or the outer surface or the lower surface of the insulating base 101 from the connection pad 106. By leading a wiring conductor (not shown) to the outer surface, the wiring conductor is led out of the recess 104.

  Note that the electronic components 107 can also be electrically connected to each other via a wiring conductor. After mounting the electronic component 107 in the concave portion 104 of the insulating base 101, the electronic component 107 is hermetically sealed by attaching the lid 111 to the upper surface of the insulating base 101 and closing the concave portion 104.

  A metallized layer 103 is formed on the upper surface of the insulating base 101 so as to surround the recess 104, and a lid 111 is joined to the metallized layer 103 by means such as welding or joining via a brazing material. Attachment of the body 111 to the insulating base 101 is performed.

  The metallized layer 103 has a thickness of about 10 to 30 μm and a width of each side of about 0.2 to 0.5 mm.

  Further, a metal frame 108 is bonded to the metallized layer 103 in advance by means such as brazing, and a metal lid 111 is placed on the metal frame 108, and the outer periphery of the lid 111 When the lid body 111 is welded to the metal frame 108 by causing the pair of roller electrodes of the seam welding machine to roll while being in contact with each other and passing a large current for welding between the roller electrodes, Since the insulating base 101 is firmly joined to the insulating base 101 by a joining means such as welding or brazing via the metal frame 108, the reliability of hermetic sealing can be further increased.

  In the case of the sealing means through the metal frame 108, a nickel plating layer is previously deposited on the surface of the metal frame 108 and the lid 111 made of metal, and the nickel plating layer is heated by the heat of seam welding. The metal frame body 108 and the lid body 111 are welded by melting a part of the metal foil or the brazing material rolled on the lower surface of the lid body 111. The insulating base 101 has a notch 102 on the side surface.

  The notch 102 has, for example, a conductive layer 109 electrically connected to the connection pad 106 attached to the surface thereof, and the electronic component 107 connected to the connection pad 106 is electrically connected to an external electric circuit (not shown). A connecting portion is formed for connection.

  The electrical connection between the connection pad 106 and the conductor layer 109 is performed, for example, by connecting the extended end of the connection pad 106 or a wiring conductor to the conductor layer 109.

  In addition, the conductor layer 109 can function as a connection terminal for rewriting the memory contents of the electronic component 107 (semiconductor element). In this case, if a crystal resonator (not shown) is mounted on the upper side or the lower side of the semiconductor element 107 in the recess 104, temperature compensation is accurately performed in accordance with the vibration characteristics of the crystal resonator, the usage environment of the electronic device, and the like. Thus, a temperature compensated crystal oscillator capable of adjusting the function of the semiconductor element 107 can be provided.

  The conductor layer 109 and the metallized layer 103 are made of a metal material such as tungsten, molybdenum, manganese, copper, silver, etc., as in the case of the connection pad 106. The conductive paste is prepared by adding a kneading agent and the like to the surface of the green sheet to be the insulating substrate 101, and the like in a predetermined pattern.

  On the exposed surfaces of the conductor layer 109, the metallized layer 103, and the connection pad 106, the conductor layer 109, the metallized layer 103, and the connection pad 106 are prevented from being oxidized and corroded, and the conductive layer 109 and a conductive terminal for rewriting the internal memory are provided. In order to further strengthen the connection between the electronic component 107 and the connection pad 106, the connection between the conductor layer 109 and the external electric circuit, etc., for example, a nickel plating layer having a thickness of about 1 to 10 μm and 0.1 It is preferable that a gold plating layer having a thickness of about 3 μm is sequentially deposited.

  In addition, the insulating base 101 has a protruding portion 105 formed thick inside the recess 104 at the side end of the notch 102. With such a structure, the mechanical strength of the frame portion 110 surrounding the concave portion 104 of the insulating base 101 can be effectively reinforced at the side end portion of the notch portion 102, that is, at a portion that is likely to be a starting point of a crack. Therefore, it is possible to prevent the insulating base 101 from being cracked due to stress such as thermal stress accompanying thermal expansion and contraction when the lid is joined to the upper surface of the insulating base 101.

  In addition, when the lid 111 is seam welded to the metal frame 108, it is necessary to melt a part of the nickel plating layer, the brazing material rolled on the lower surface of the lid 111, etc. A high temperature exceeding 1 is applied. Even in such a case, since the mechanical strength of the insulating base 101 where the notch 102 where the crack is likely to be formed is formed is effectively reinforced as described above, the insulating base 101 is cracked. Can be effectively prevented from occurring.

  For example, when the insulating base 101 has a rectangular shape as shown in FIG. 1A and two cutouts 102 are formed on opposite sides of the long side, first, the heat is applied from the metal by seam welding. The lid body 111 is applied to a high temperature, and a part of the nickel plating layer, the brazing material rolled on the lower surface of the lid body 111, and the like are melted through the lid body 111. Furthermore, since the lid body 111 that has reached a high temperature exceeding 1000 ° C. is naturally cooled gradually, the end portion of the lid body 111 (in the example of FIG. 1, the lid body 111 is rectangular and the two sides face each other in a short direction). Thus, the lid body 111 is thermally contracted from the center to the center of the recess 104. In this case, the stress such as thermal stress accompanying thermal expansion and contraction when the lid 111 is joined to the upper surface of the insulating base 101 is a weak portion on the outer peripheral side surface of the insulating base 101, that is, a notch on the side surface of the insulating base 101. It has been confirmed by thermal stress simulation that it tends to concentrate on the side end portion 102 (the side end portion of the cutout portion 102, particularly the short side of the insulating base 101).

  Therefore, by forming the protrusion 105 thickly inside the recess 104 at the side end of the notch 102 in this way, even if stress is concentrated on the side end of the notch 102, cracks do not occur. The insulating base 101 can be reinforced, and cracks can be prevented from occurring in the insulating base 101 due to stress such as thermal stress accompanying thermal expansion and contraction when the lid 111 is joined to the upper surface of the insulating base 101.

  Further, a metallized layer may be formed on the surface of the protruding portion 105 in the same manner as the metallized layer 103 on the upper surface of the insulating base 101. In this way, by forming a metallized layer on the surface of the protruding portion 105, the protruding portion 105 and the metal frame 108 are filled with the brazing filler fillet on the concave side as well as the outer peripheral portion of the brazing metalized layer 103. Since the metal frame 108 and the lid body 111 are thermally contracted after the lid body 111 is joined to the metal frame body 108 by the seam weld method, the stress generated by the thermal contraction is applied to the insulating base body. Even when applied to the metallized layer 103 on the upper surface of 101, the stress is well dispersed in the fillet formed on the protruding portion 105 of the metallized layer 103 and the braze fillet on the outer peripheral portion of the metal frame 108. As a result, the metal frame 108 can be more reliably prevented from peeling from the insulating base 101 and the metallized layer 103 is peeled from the insulating base 101. Rukoto can also be prevented. Therefore, the reliability of hermetic sealing can be further increased.

  In the electronic component storage package of the present invention, it is preferable that the width of the protrusion 105 is wider than the width of the notch 102. By forming the protruding portion 105 so as to be wider than the notched portion 102 in this way, the mechanical strength of the insulating base 101 surrounding the recess 104 can be further effectively improved. It can prevent more reliably that a crack generate | occur | produces.

  Here, the molten brazing material wets and spreads on the gold plating layer deposited on the surface of the metal frame 108 to form a fillet of the brazing material. At this time, the metallized layer is formed through the lid 111. When the frame body 103 (the ceramic portion) on the lower surface of 103 and the lower surface thereof are exposed to a high temperature, a large thermal shock may occur and a crack may be generated in the insulating substrate 101.

  Even in such a case, the rigidity of the side end portion of the notch portion 102 on the side surface of the insulating base 101 where the stress is concentrated can be increased by forming the protruding portion 105 to be wider than the width of the notch portion 102. Since it can ensure, a crack can be prevented more effectively.

  In the electronic component storage package of the present invention, it is preferable that the protruding portion 105 is formed between the plurality of connection pads 106. When the electronic component 107 is electrically connected to the connection pad 106 via an electrical connection means such as a bonding wire or solder, the protrusion 105 prevents the connection between the electronic component 107 and the connection pad 106. There is no worsening. Therefore, it is possible to provide the insulating substrate 101 which is excellent in the reliability of hermetic sealing and excellent in mountability and connectivity in the recess 104 of the electronic component 107.

  In addition, since the protruding portion 105 is formed between the connection pads 106 formed in the recess 104, an electrical short circuit occurs when the adjacent connection pads 106 are, for example, connection pads 106 having different potentials. Also acts as an insulator to prevent (short).

  The electronic device according to the present invention includes any one of the above-described electronic component storage packages, an electronic component 107 housed in the recess 104 of the electronic component storage package, and electrically connected to the plurality of connection pads 106, and the metallized layer 103. A metal frame 108 bonded to the metal frame 108 and a lid 111 bonded to the metal frame 108.

  With such a structure, the lid 111 is firmly bonded to the insulating base 101 via the metal frame 108, and the lid 111 is bonded to the metal frame 108 on the upper surface of the insulating base 101. It is possible to provide an electronic device excellent in hermetic sealing performance and reliability in which cracks are effectively prevented from occurring in the insulating substrate 101 due to stress such as stress accompanying thermal expansion and contraction.

  When the metal frame 108 is brazed to the surface of the metallized layer 103, in order to improve the wettability with the brazing material, for example, a nickel plating layer having a thickness of about 0.5 to 5 μm is formed on the surface of the metallized layer 103. It may be pre-deposited.

  The metal frame 108 is made of a metal material such as an iron-nickel alloy or an iron-nickel-cobalt alloy, and functions as a base metal member for welding the lid 111 to the insulating base 101. For example, the inner circumference of the metal frame 108 is the same as the outer dimension of the recess 104, the thickness is about 0.1 to 0.5 mm, and the width of each side is about 0.15 to 0.45 mm. is there.

  As a method of joining the metal lid 111 to the metallized layer 103, for example, a silver brazing having a thickness of 20 to 50 μm is previously applied to the lower surface of the lid 111, and the lower surface to which the silver brazing has been applied is applied. By placing on the metallized layer 103 and heating with seam welding, electron beam or the like, the lid 111 and the metallized layer 103 can be easily brazed with good airtightness.

  In addition, this invention is not limited to the example of the above-mentioned embodiment, A various change is possible. For example, in FIG. 1 illustrating the embodiment of the present invention, the insulating base 101 has three layers (two frames and one substrate), but may be formed by laminating four or more ceramic layers. Good.

  In FIG. 1, the connection pads 106 are formed at a total of six locations on the long side of the inner surface of the concave portion 104, but in other locations and numbers depending on the arrangement of the electrodes of the electronic component 107. You may form as follows.

(A) is a top view which shows an example of embodiment of the electronic component storage package and electronic device of this invention, (b) is a side perspective view of FIG. (A) is a top view which shows an example of embodiment of the conventional electronic component storage package and electronic device, (b) is a side perspective view of FIG.

Explanation of symbols

101 ... Insulating substrate 102 ... Notch 103 ... Metallized layer 104 ... Recess 105 ... Projection 106 ... Connection pad 107 .... Electronic components

Claims (4)

An insulating base having a recess for accommodating an electronic component on the upper surface and a notch on a side surface; and a plurality of connection pads formed in the recess of the insulating base and electrically connected to the electronic component; A metallization layer formed on the upper surface of the insulating base so as to surround the concave portion, and the insulating base has a protrusion formed on the inner side surface of the concave corresponding to the outer end of the notch. A package for storing electronic components. 2. The electronic component storing package according to claim 1, wherein a width of the protruding portion is wider than a width of the notch portion. The electronic component storage package according to claim 1, wherein the protrusion is formed between the plurality of connection pads. The electronic component storage package according to any one of claims 1 to 3, the electronic component accommodated in the recess of the electronic component storage package, and electrically connected to the plurality of connection pads, An electronic device comprising: a metal frame bonded to the metallized layer; and a lid bonded to the metal frame.

Images