JP6176057B2 - Electronic component package base, electronic component package - Google Patents

Description

  The present invention relates to a base for an electronic component package used in an electronic device or the like, and an electronic component package.

  Examples of electronic components that require hermetic sealing include piezoelectric vibration devices such as crystal resonators, crystal filters, and crystal oscillators. In each of these products, a metal thin film electrode is formed on the surface of the crystal diaphragm, and the crystal diaphragm (specifically, the metal thin film electrode) is hermetically sealed to protect the metal thin film electrode from the outside air. .

  Due to the demand for surface mounting of components, these piezoelectric vibration devices are increasingly being stored in a package made of an insulating material such as ceramic. For example, Patent Document 1 discloses a package made of a ceramic material, which includes a base (mounting substrate) having a quartz vibration plate mounting portion and a lid (cover) having an inverted concave cross section, and these are hermetically sealed. A configuration that is mounted on a circuit board and bonded via a conductive bonding material such as solder is disclosed.

  In this conventional piezoelectric vibration device, a terminal electrode is formed on the bottom surface of the base (back surface of the base), and the terminal electrode is formed on the side surface of the base in order to check the connection state due to the solder (conductive bonding material) creeping up. It extends from the bottom of the base to the side by the castellation.

  By the way, a so-called glass epoxy substrate in which a mesh-like glass fiber is impregnated with an epoxy resin material is widely used for a circuit board on which the conventional piezoelectric vibration device is mounted because of ease of processing and cost advantages. . In addition, a solder paste is applied to the upper part of the electrode pattern of the circuit board by a method such as screen printing. Then, the terminal electrode of the package of the piezoelectric vibration device is mounted on the electrode pattern of the circuit board, and the solder paste is melted in a melting furnace (such as a heating furnace) to cause piezoelectric vibration on the circuit board. Solder the device.

JP 2002-76813 A

  However, due to a difference in thermal expansion coefficient between the package and the circuit board, stress may be generated in the solder that joins the package and the circuit board, and cracks may occur. In particular, when a ceramic material such as alumina is used as a package and a glass epoxy board is used as a circuit board, and when it is used for applications that are used in harsh environments such as in-vehicle use, high and low temperatures Since the package and the circuit board are used in an environment, fatigue breakdown is likely to occur from the solder due to the difference between the thermal expansion coefficient of the package and the thermal expansion coefficient of the circuit board. As described above, the problem of solder cracks, which did not become a serious problem in normal temperature environments, appears prominently in high and low temperature environments, and when an impact is applied to the package and circuit board, peeling occurs from the solder crack portions. (Open state), and finally there was a problem of disconnection.

  The present invention has been made to solve the above-described problems, and has an object to provide an electronic component package base and an electronic component package that improve the reliability of mounting and bonding between the electronic component package and the circuit board. To do.

  The inventor has found that in the conductive bonding material for bonding the external circuit board and the base of the electronic component package, a crack occurs in the outer peripheral portion of the conductive bonding material, and the thermal expansion and thermal contraction of these bonding portions are repeated. (Hereinafter referred to as the thermal shock stress), the crack progresses only along the joint portion of the conductive joint material joining the circuit board and the base, and the thermal shock of the joint portion. It has been found that the crack progresses linearly from the maximum stress portion to the minimum stress portion of the thermal shock. In particular, when the base bottom surface (base back surface) is rectangular in plan view, the maximum stress portion is a corner portion of the base bottom surface, and the crack of the conductive bonding material is the base point from the joint portion closest to this corner portion, It has been found that cracks progress linearly toward the vicinity of the center point of the base bottom surface, which is the minimum stress portion, that is, from the corner portion of the base bottom surface to the oblique direction near the center point. Therefore, the present invention proposes the best means that can prevent or delay the progress of cracks in the conductive bonding material.

In the present invention, in the base of the electronic component package that holds the electronic component element, the bottom surface of the base is rectangular in plan view, and at least a pair of terminal electrodes that are bonded to an external circuit board using a conductive bonding material are formed. The terminal electrode is formed with a thin area where only the terminal electrode is formed, a thick area where a bump is formed on the terminal electrode, and an electrodeless area inside the area of the terminal electrode. On a straight line from the corner of the bottom surface to the center point of the base bottom surface, a part of the thin region, a part of the non-electrode region, and a part of the thick region are disposed, and the terminal electrode includes An electrode region in which an electrode is formed and an electrodeless region in which no electrode is formed are formed, and the electrode region is in the vicinity of one or more corners of the base bottom surface and two or more sides in contact with the corners And the outer periphery of the belt-shaped portion And a central part wider than the outer peripheral part formed at a position close to the center point of the base bottom surface through a bent part, and is formed between the outer peripheral part and the central part as the electrodeless region And a substantially L-shaped or substantially U-shaped cutout portion formed along one or more corners of the base bottom surface and two or more sides in contact with the corners, Bumps are formed on the substrate .

  With the above configuration, in the conductive bonding material for bonding the external circuit board and the base of the electronic component package, the thickness of the conductive bonding material to be bonded in the thin region, the thick region, and the non-electrode region is three. It can be made different. For this reason, when a crack of the conductive bonding material progresses in an oblique direction from a region close to the corner of the base bottom surface toward a region close to the center point of the base bottom surface having a relatively small stress in the central portion. Furthermore, it is possible to intentionally create three or more portions serving as crack barriers in the thickness direction of the conductive bonding material.

  More specifically, an inflection point in the thickness direction can be formed in the crack of the conductive bonding material that develops between the thin-walled region and the thick-walled region. Since the crack of the adhesive bonding material can be shifted in a direction other than the oblique direction in plan view, these can be combined organically and the progress of the crack can be further delayed.

  As a result, it is strong against thermal shock stress and can improve the reliability of mounting bonding between the electronic component package and the circuit board.

  According to the above configuration, the terminal electrode is further provided with an electronic component package on the outer peripheral portion of the belt extending in the state of being close to one or more corners of the base bottom surface and two or more sides in contact with the corners. A difference in thermal expansion coefficient is generated between the base and the circuit board, and the stress of the thermal shock is first applied to the conductive bonding material, resulting in a region where the stress is relatively large. On the other hand, an electronic component package is formed in a central portion formed from the outer peripheral portion to a center point of the base bottom surface via a bent portion and wider than the outer peripheral portion and formed with bumps. Even if a thermal expansion coefficient difference is generated between the base and the circuit board and the stress of the thermal shock is applied to the conductive bonding material, the stress is not easily applied, and the area is relatively small.

  However, in the present invention, from the region near the corner of the base bottom having a relatively large stress in the outer peripheral portion, the region approaching the center point of the base bottom having a relatively small stress in the central portion. The crack of the conductive bonding material does not progress in the oblique direction, but the crack of the conductive bonding material is suppressed along the extending direction of the belt-shaped outer peripheral portion in a state shifted from the oblique direction in plan view. You can make progress.

  Further, in the central portion formed at a position close to the central point of the base bottom surface from the outer peripheral portion via the bent portion, the direction of the crack of the conductive bonding material progresses through the inflection point in plan view. Therefore, it can be set as the structure effective in further suppressing that the crack of an electroconductive joining material progresses. In addition, since the conductive bonding material for bonding the base and the circuit board is also bonded in a wide (large area) state at the central portion wider than the outer peripheral portion, the progress of cracks at the central portion is further suppressed. In addition, it is possible to secure an area where it is easy to ensure electrical connection by improving connectivity.

  In the present invention, in addition to the above-described configuration, the terminal electrode has a belt-shaped outer peripheral portion that extends in a state of being close to one or more corners of the base bottom surface and two or more sides in contact with the corners. And a central portion formed so as to extend from the outer peripheral portion through a bent portion in a direction close to the center point of the base bottom surface, and a bump may be formed in the central portion.

  According to the above configuration, the terminal electrode is further provided with an electronic component package on the outer peripheral portion of the belt extending in the state of being close to one or more corners of the base bottom surface and two or more sides in contact with the corners. A difference in thermal expansion coefficient is generated between the base and the circuit board, and the stress of the thermal shock is first applied to the conductive bonding material, resulting in a region where the stress is relatively large. On the other hand, the base and the circuit board that form the electronic component package are formed by extending from the outer peripheral portion through the bent portion in a direction close to the center point of the base bottom surface, and in the central portion where the bump is formed. Even if a thermal expansion coefficient difference is generated between them and the stress of the thermal shock is applied to the conductive bonding material, the stress is not easily applied, and the region becomes relatively small.

  However, in the present invention, from the region near the corner of the base bottom having a relatively large stress in the outer peripheral portion, the region approaching the center point of the base bottom having a relatively small stress in the central portion. The crack of the conductive bonding material does not progress in the diagonal direction, but in a state where the crack of the conductive bonding material is suppressed along the extending direction of the belt-shaped outer peripheral portion in a state shifted from the diagonal direction in plan view. You can make progress.

  Further, in the central portion further extended from the outer peripheral portion through the bent portion in the direction close to the central point of the base bottom surface, the direction of the crack of the conductive bonding material progresses through the inflection point in plan view. Therefore, it can be set as the structure effective in further suppressing that the crack of an electroconductive joining material progresses.

  The electronic component package may further include a lid that hermetically seals the electronic component element with respect to the base of the electronic component package described above. With this configuration, an electronic component package hermetically sealed using a base that can obtain the above-described operational effects can be obtained. Therefore, an electronic component package that is inexpensive and can be downsized to improve the reliability of circuit board mounting and bonding. Can be provided.

  According to the present invention, an electronic component package that can further reduce the adverse effects of cracks (for example, solder cracks) in a conductive bonding material due to thermal shock stress, and can improve the reliability of circuit board mounting bonding at low cost. And a package for electronic components can be provided.

1 is a bottom view of a surface-mounted crystal resonator showing an embodiment of the present invention. Sectional drawing along the AA line of the state which mounted the surface mount-type crystal oscillator of FIG. 1 in the circuit board. The bottom view of the surface mount-type crystal resonator which shows the modification 1 of embodiment of this invention. Sectional drawing along the BB line of the state which mounted the surface mount-type crystal oscillator of FIG. 3 in the circuit board. FIG. 4 is a cross-sectional view taken along the line CC in a state where the surface-mount type crystal resonator of FIG. 3 is mounted on a circuit board. FIG. 10 is a bottom view of a surface-mounted crystal resonator showing a second modification of the embodiment of the present invention. FIG. 10 is a bottom view of a surface-mount type crystal resonator showing a third modification of the embodiment of the present invention. The bottom view of the surface mount-type crystal resonator which shows the modification 4 of embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each of the following embodiments, the case where the present invention is applied to a surface-mount type crystal resonator as a package for an electronic component is shown.

  As shown in FIGS. 1 and 2, a surface-mount type crystal resonator according to an embodiment of the present invention includes a crystal diaphragm 3 that is an electronic component element, and a crystal diaphragm 3 that has a recess that is open at the top. A base 1 to be held (stored), and a lid 2 that hermetically seals the crystal diaphragm 3 held on the base 1 by being joined to the opening of the base 1.

  The base 1 is a rectangular parallelepiped as a whole, and has a configuration in which a ceramic such as alumina and a conductive material such as tungsten or molybdenum are appropriately laminated. As shown in FIG. 2, the base 1 includes a storage section 10 that is concave in a sectional view, and a bank portion 11 that is provided around the storage section 10 so as to surround the storage section 10. Specifically, the base 1 is a rectangular (planar view rectangular) flat plate-shaped ceramic base base 1a, and a ceramic having a large central portion and an outer size (planar view outer size) substantially equal to the base base 1a. The base body 1a, the frame body 1b, and the sealing member 11a are integrally fired. The top surface of the bank portion 11 (frame body 1b) is flat, and a sealing member 11a (a sealing material, a metal layer, or the like) is formed on the bank portion 11. In the present embodiment, for example, a configuration in which glass is formed as the sealing member 11a is shown. However, when the lid 2 described later is a metal lid, nickel is formed on the upper surface of the metallized layer made of tungsten, molybdenum, or the like as the sealing member 11a. It is good also as a structure by which each layer of the plating layer and the gold plating layer was formed, and also the structure by which the metal ring was formed in the upper part of these each layer.

  In addition, four corners (K1, K2, K3, K4) of the outer periphery (outer peripheral edge in plan view) of the base 1, and the side surfaces of the four corner bases 1 are vertically moved from the base bottom surface to the top surface (top surface). Castellations C1, C2, C3, and C4 are formed.

  The bottom surface of the base 1 (the back surface of the base 1) has a rectangular shape in plan view, and terminal electrodes 12a and 12b having a rectangular shape in plan view are formed along the short sides (H1 and H3) facing the bottom surface of the base. The terminal electrodes 12a and 12b are formed with electrode regions 121a and 121b where electrodes are formed, and non-electrode regions 122a and 122b where electrodes along the adjacent sides of the base bottom surface are not formed.

  The electrode areas 121a and 121b include corners (K1, K2), corners (K3, K4) on the bottom surface of the base 1, sides (H1, H2, and H4) in contact with the corners, sides (H2, H3, and H4). To the center point O of the bottom surface of the base 1 through the bent portions (125a, 125a) and the bent portions (125b, 125b) from the outer peripheral portions 123a, 123b and the bent outer portions 123a, 123b. The center portions 124a and 124b are formed at close positions (close directions) and wider than the outer peripheral portions 123a and 123b (having a larger area than the outer peripheral portions).

  The electrodeless regions 122a and 122b are formed between the outer peripheral parts 123a and 123b and the central parts 124a and 124b, and the bottom surface corners (K1, K2), corners (K3, K4) of the base 1 and the corners. Strip-shaped notches 126a and 126b formed along sides (H1, H2, and H4) in contact with the sides and sides (H2, H3, and H4). In the present embodiment, for example, the cutout portions 126a and 126b are short sides H1 and H3 and long sides H2 and H4 that are close to the bottom surface of the base 1 of the terminal electrodes 12a and 12b. It is formed in a substantially U shape along the line.

  The terminal electrodes 12a and 12b are respectively connected to electrode pads 14a and 14b formed on the bottom surface inside the base 1 via side terminal electrodes 13a, 13b, 13c and 13d formed on the castellations C1, C2, C3 and C4. The electrode pad 14b extends and is electrically connected. In other words, in the regions near the corners (K1, K2) and corners (K3, K4) of the bottom surface of the base 1 in the outer peripheral parts 123a, 123b, the other terminals are connected to the side terminal electrodes 13a, 13b, 13c, 13d. It is formed wider than the outer peripheral area. With this configuration, the region close to the corner of the base in the outer peripheral portion, which is the maximum stress portion, is formed wider so that the connectivity in this region is enhanced and the progress of cracks is also suppressed.

  These terminal electrodes 12a, 12b, side surface terminal electrodes 13a, 13b, 13c, 13d, and electrode pads 14a, 14b are formed by metallizing a metallized material such as tungsten or molybdenum integrally with the base 1 to form a metallized portion. Nickel plating is formed on the top, and gold plating is formed on the top thereof.

  Between the electrode pads 14a and 14b, a crystal diaphragm 3 (an electronic component element in the present invention) is mounted. A pair of excitation electrodes and extraction electrodes (not shown) are formed on the front and back surfaces of the crystal diaphragm 3. The pair of excitation electrodes and extraction electrodes are in contact with, for example, the quartz diaphragm 3 (from the top of the quartz diaphragm 3) in the order of chromium, gold, chromium, gold, chromium, chromium, silver, chromium, or chromium, It is formed by laminating in the order of silver. Each of these electrodes (a pair of excitation electrode and extraction electrode) can be formed by a thin film forming means such as a vacuum evaporation method or a sputtering method. The lead electrode of the crystal diaphragm 3 is conductively bonded to the electrode pads 14 a and 14 b by a conductive bonding material (not shown), and the crystal diaphragm 3 is held on the base 1. For example, a conductive bonding material such as a conductive resin adhesive, a metal bump, a metal plating bump, or a brazing material is used for conductive bonding between the excitation electrode of the crystal diaphragm 3 and the electrode pads 14a and 14b of the base 1. Can do.

  As the lid 2 that hermetically seals the base 1, a ceramic material such as plate-like alumina formed with a sealing member 11 a such as a glass sealing material is used. The plan view outline of the lid 2 is substantially the same as or slightly smaller than the outline of the base 1. The lid 2 is not limited to a ceramic material but may be a glass material or a metal material.

  The crystal vibrating plate 3 is housed in the storage portion 10 of the base 1 and covered with the lid 2 and hermetically sealed by a technique such as fusion bonding using a heating furnace, whereby a surface-mounted crystal resonator (electronic The component package is completed. The method for hermetic sealing between the base 1 and the lid 2 is not limited to fusion bonding, and other methods such as welding and brazing are used depending on various materials (base, lid, sealing member, etc.). be able to. Further, as shown in FIG. 2, the finished crystal unit is joined to the upper part of the electrode patterns 4a and 4b of the circuit board 4 made of glass epoxy material via a conductive joining material D such as solder. .

  Further, in the first modification of the embodiment of the present invention shown in FIGS. 3, 4, and 5, bumps 16a and 16b are formed on the central portions 124a and 124b of the terminal electrodes 12a and 12b, respectively, in the embodiment described above. The vias 17a and 17b for connecting to the electrode pads 14a and 14b are formed below the bumps 16a and 16b of the central portions 124a and 124b (formed at positions where the bumps and vias overlap in plan view). Is different. Other parts adopt the same configuration, and the detailed description is omitted by assigning the same number.

  That is, bumps 16a and 16b having substantially the same shape (similar shape in plan view) are formed on the upper portions of the central portions 124a and 124b of the terminal electrodes 12a and 12b. Has been. These bumps 16a and 16b are integrally formed by laminating the same material metallization (tungsten, molybdenum, etc.) in substantially the same shape on top of the metallization of the terminal electrodes 12a and 12b. Therefore, the bumps 16a and 16b can be formed very easily and inexpensively. The terminal electrodes 12a and 12b and the bumps 16a and 16b are formed by firing these metallized materials integrally with the base 1, forming nickel plating on the metallized upper part, and forming gold plating on the upper part. .

  From the above configuration, as shown in FIG. 5, the terminal electrodes 12a and 12b have thin areas 127a and 127b in which only terminal electrodes are formed, and thick areas in which bumps smaller than the terminal electrodes are formed on the terminal electrodes. 128a, 128b and non-electrode regions 122a, 122b inside the terminal electrode region are formed, and straight lines from the respective corners (K1, K2, K3, K4) of the bottom surface of the base 1 toward the center point O of the bottom surface of the base 1 Above, at least a part of the thin areas 127a and 127b, a part of the non-electrode areas 122a and 122b, and a part of the thick areas 128a and 128b are disposed. In the configuration of FIG. 5, from each corner (K1, K2, K3, K4) toward the center point O of the bottom surface of the base 1, a part of the thin areas 127a, 127b, a part of the non-electrode areas 122a, 122b, a thin wall A part of the areas 127a and 127b, a part of the thick areas 128a and 128b, and a part of the thin areas 127a and 127b are arranged in this order.

  Further, in the first modification, vias 17a and 17b filled with the same metallized metal in the holes penetrating from the center portions 124a and 124b to the bottom surface inside the base 1 among the terminal electrodes 12a and 12b on the bottom surface of the base 1 are provided. Forming. The electrode pads 14a formed on the bottom surface inside the base 1 through the vias 17a and 17b as well as the side terminal electrodes 13a, 13b, 13c and 13d formed in the castellations C1, C2, C3 and C4. 14b (electrode pad 14b is not shown) is electrically connected. According to this configuration, the vias 17a and 17b can be formed in the central portion where the stress is smaller and the solder cracks progress slowly in the terminal electrode, and the electrical bonding with the electrode pads 14a and 14b can be made more reliable. The terminal electrodes 12a and 12b can be prevented from being opened and not functioning as electronic components. The vias 17a and 17b are formed at positions close to the center point O on the bottom surface of the base of the terminal electrodes 12a and 12b, so that electrical connection points accompanying the progress of solder cracks can be secured for a long period of time. More desirable in terms.

  Further, in the second modification of the embodiment of the present invention shown in FIG. 6, a four-terminal structure in which each terminal electrode is formed in four corners with respect to the above-described embodiment, and the shape of the notch as an electrodeless region is substantially omitted. The difference is that it is L-shaped. Other parts adopt the same configuration, and the detailed description is omitted by assigning the same number.

  That is, terminal electrodes 15a, 15b, 15c, and 15d having a rectangular shape in plan view are formed in proximity to the four corners (K1, K2, K3, and K4) of the base bottom surface. The terminal electrodes 15a, 15b, 15c, and 15d include electrode regions 151a, 151b, 151c, and 151d where electrodes are formed, and electrodeless regions 152a, 152b, 152c where electrodes along adjacent sides of the base bottom surface are not formed. 152d is formed.

  The electrode areas 151a, 151b, 151c, and 151d include the bottom surface corner (K1), corner (K2), corner (K3), corner (K4) of the base 1, and sides (H1 and H4) in contact with the corner, Band-shaped outer peripheral portions 153a, 153b, 153c, and 153d extending in the state of being close to the sides (H1 and H2), the sides (H2 and H3), and the sides (H3 and H4), and the outer peripheral portions 153a, 153b, 153c, and 153d From the center point O of the bottom surface of the base 1 through the bent portions (155a, 155a), the bent portions (155b, 155b), the bent portions (155c, 155c), and the bent portions (155d, 155d). And has center portions 154a, 154b, 154c, and 154d that are wider than outer peripheral portions 153a, 153b, 153c, and 153d (having a larger area than the outer peripheral portions).

  The electrodeless regions 152a, 152b, 152c, and 152d are formed between the outer peripheral portions 153a, 153b, 153c, and 153d and the central portions 154a, 154b, 154c, and 154d, and the corner (K1) of the bottom surface of the base 1 is formed. Corner (K2), Corner (K3), Corner (K4), Side (H1 and H4), Side (H1 and H2), Side (H2 and H3), Side (H3 and H4) in contact with the corner It has the strip-shaped notch parts 156a, 156b, 156c, 156d formed along. In this embodiment, for example, the notches 156a, 156b, 156c, and 156d are formed in a strip shape along the corners and sides, and the long sides of the terminal electrodes 12a and 12b that are close to the short sides H1 and H3 that are close to the bottom surface of the base 1. It is formed in a substantially L shape along the sides H2 and H4.

  Part of each terminal electrode 15a, 15b, 15c, 15d is formed on the bottom surface inside the base 1 via the side terminal electrodes 13a, 13b, 13c, 13d formed in the castellations C1, C2, C3, C4. The electrode pads 14a and 14b (the electrode pad 14b is not shown) are extended and electrically connected. That is, in the outer peripheral portions 153a, 153b, 153c, and 153d, in the regions close to the corner (K1), corner (K2), corner (K3), and corner (K4) of the bottom surface of the base 1, the side terminal electrodes 13a, 13b, In order to connect with 13c and 13d, it forms wider than the area | region of another outer peripheral part. With this configuration, the region close to the corner of the base in the outer peripheral portion, which is the maximum stress portion, is formed wider so that the connectivity in this region is enhanced and the progress of cracks is also suppressed.

  In the embodiment of the present invention, a form as shown in FIG. 7 (Modification 3) may be used. That is, FIG. 7 (Modification 3) is different from the above embodiment in that the terminal electrodes 18a and 18b are not rectangular but have a band shape. More specifically, the base 1 is extended in the state of being close to the corners (K1, K2), corners (K3, K4) of the base 1, the sides (H1 and H2) and the sides (H3 and H4) in contact with the corners. Band-shaped outer peripheral portions 183a and 183b and formed extending from the outer peripheral portions 183a and 183b to the center point O of the bottom surface of the base 1 via the bent portion (185a) and the bent portion (185b). Center portions 184a and 184b which are wider than the portions 183a and 183b (having a larger area than the outer peripheral portion).

  The terminal electrodes 18a and 18b are respectively connected to electrode pads 14a and 14b formed on the bottom surface inside the base 1 through side terminal electrodes 13a, 13b, 13c and 13d formed on the castellations C1, C2, C3 and C4. The electrode pad 14b extends and is electrically connected. In other words, in the outer peripheral portions 183a and 183b, in the region close to the corners (K1, K2) and corners (K3, K4) of the bottom surface of the base 1, in order to connect to the side terminal electrodes 13a, 13b, 13c, 13d, etc. It is formed wider than the outer peripheral area. With this configuration, the region close to the corner of the base in the outer peripheral portion, which is the maximum stress portion, is formed wider so that the connectivity in this region is enhanced and the progress of cracks is also suppressed.

  In the third modification, vias 17a and 17b filled with the same metallized metal in the holes penetrating from the central portions 184a and 184b to the bottom surface inside the base 1 among the terminal electrodes 18a and 18b on the bottom surface of the base 1 are provided. Forming. The electrode pads 14a formed on the bottom surface inside the base 1 through the vias 17a and 17b as well as the side terminal electrodes 13a, 13b, 13c and 13d formed in the castellations C1, C2, C3 and C4. 14b (electrode pad 14b is not shown) is electrically connected. According to this configuration, the vias 17a and 17b can be formed in the central portion where the stress is smaller and the solder cracks progress slowly in the terminal electrode, and the electrical bonding with the electrode pads 14a and 14b can be made more reliable. The terminal electrodes 18a and 18b can be prevented from being opened and not functioning as electronic components. The vias 17a and 17b are formed at positions close to the center point O of the base bottom surface of the terminal electrodes 18a and 18b, so that an electrical connection point accompanying the progress of solder cracks can be secured for a long period of time. More desirable in terms.

  In the embodiment of the present invention, a form as shown in FIG. 8 (Modification 4) may be used. That is, in FIG. 8 (Modification 4), with respect to the embodiment of FIG. 3 (Modification 1), the corners (K1, K2) and corners (K3, K4) of the bottom surface of the source 1 of the outer peripheral portions 123a, 123b. ) Is different in that a convex portion (129a, 129a, 129a, 129a) protruding in a direction close to the center point O of the bottom surface of the base 1 is formed. Other parts adopt the same configuration, and the detailed description is omitted by assigning the same number. In the embodiment of the present invention, the protrusions (129a, 129a, 129a, 129a) are further shifted so that cracks propagate in the direction opposite to the diagonal direction near the center point O from the corners of the bottom surface of the base 1. be able to. As a result, compared with the first modification, the cracks of the conductive bonding material D further progress along the belt-shaped outer peripheral portions 123a and 123b and the extending direction of the bent portions (125a and 125a) from the outer peripheral portions 123a and 123b. It is effective in delaying to do.

  With the configuration of the above-described embodiment, the crack of the conductive bonding material D progresses in an oblique direction from a region close to the corner of the bottom surface of the base 1 of each terminal electrode toward a region close to the center point O of the base bottom surface. Instead of cracking the conductive bonding material D along the extending direction of the belt-shaped outer peripheral portions (123a, 123b, 153a, 153b, 153c, 153d, 183a, 183b) in a state shifted from the oblique direction in plan view. Can be progressed in a suppressed state. Further, a central portion (124a) further extending from the outer peripheral portion through a bent portion (125a, 125b, 155a, 155b, 155c, 155d, 185a, 185b) in a direction close to the center point O of the bottom surface of the base 1. , 124b, 154a, 154b, 154c, 154d, 184a, 184b), the direction of the crack in the conductive bonding material D is propagated through the inflection point in plan view. It can be set as the structure effective in further suppressing that a crack progresses. In addition, in the central part (124a, 124b, 154a, 154b, 154c, 154d, 184a, 184b) wider than the outer peripheral part (123a, 123b, 153a, 153b, 153c, 153d, 183a, 183b), the base 1 and circuit Since the conductive bonding material D for bonding to the substrate 4 is also bonded in a wide state (large area), not only is the crack progressed at the center, but also the connection is improved and conduction is ensured. An area that can be easily secured can be secured. As a result, it is strong against thermal shock stress and can improve the reliability of mounting bonding between the electronic component package and the circuit board.

  In the first and fourth modifications, the terminal electrodes 12a and 12b are formed with thin regions 127a and 127b in which only the terminal electrodes are formed, and bumps 16a and 16b smaller than the terminal electrodes are formed on the terminal electrodes. Thick regions 128a and 128b and non-electrode regions 122a and 122b inside the terminal electrode region are formed, and the center point O of the bottom surface of the base 1 from each corner (K1, K2, K3, K4) of the bottom surface of the base 1 is formed. On the straight line directed to, a part of the thin areas 127a and 127b, a part of the non-electrode areas 122a and 122b, a part of the thin areas 127a and 127b, a part of the thick areas 128a and 128b, and a part of the thin areas 127a and 127b. Are arranged in order. For this reason, in the conductive bonding material D for bonding the external circuit board 4 and the base 1 of the electronic component package, the thin regions 127a and 127b, the thick regions 128a and 128b, and the non-electrode regions 122a and 122b are bonded. The thickness of the conductive bonding material D can be varied to three or more. When the crack of the conductive bonding material D progresses in an oblique direction from a region close to the corner of the bottom surface of the base 1 toward a region close to the center point O of the bottom surface of the base 1, the conductive bonding material It is possible to intentionally create three or more portions that serve as crack barriers in the thickness direction of D. That is, an inflection point in the thickness direction can be formed in the crack of the conductive bonding material D that develops between 127a and 127b and the thick regions 128a and 128b. In the portion where the electrodeless regions 122a and 122b are interposed, the cracks of the conductive bonding material D that develops can be shifted in a direction other than the oblique direction in plan view. These are organically combined, and the progress of cracks can be further delayed. As a result, it is strong against thermal shock stress and can improve the reliability of mounting bonding between the electronic component package and the circuit board.

  With the above configuration, it is possible to further reduce and prevent the adverse effects of cracks (for example, solder cracks) in conductive bonding materials due to thermal shock stress, and for electronic components that are inexpensive and improve the reliability of circuit board mounting bonding. A package base and an electronic component package can be provided.

  In the above-described embodiment, a surface-mount type crystal resonator is taken as an example, but the present invention can also be applied to other surface-mount type electronic component packages used in electronic devices such as crystal filters and crystal oscillators. Further, although a ceramic material is disclosed as an insulating package (base), a glass material or crystal may be used. Although metallization is disclosed as the metal film of the terminal electrode, a plating material may be used. Although the number of terminal electrodes has been described as being 2 terminals and 4 terminals, it can also be applied to those having 5 terminals or more.

  The present invention can be implemented in various other forms without departing from the spirit or main features thereof, and should not be interpreted in a limited manner. The scope of the present invention is indicated by the claims, and is not limited by the text of the specification. Further, all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

  The present invention can be applied to an electronic component package such as a crystal resonator and a base of an electronic component package.

1 Base 2 Lid 3 Crystal Diaphragm (Electronic Component Element)
4 Circuit board

Claims (3)

In the base of the electronic component package that holds the electronic component element,
The base bottom has a rectangular shape in plan view, and is formed with at least a pair of terminal electrodes that are bonded to an external circuit board using a conductive bonding material,
In the terminal electrode, a thin region where only the terminal electrode is formed, a thick region where a bump is formed on the terminal electrode, and an electrodeless region inside the region of the terminal electrode are formed,
On a straight line from the corner of the base bottom surface toward the center point of the base bottom surface, at least a part of the thin region, a part of the non-electrode region, and a part of the thick region are disposed,
The terminal electrode is formed with an electrode region in which an electrode is formed and an electrodeless region in which no electrode is formed,
As the electrode region, a belt-like outer peripheral portion extending in the state of being close to one or more corners of the base bottom surface and two or more sides in contact with the corner, and a base bottom surface via a bent portion from the outer peripheral portion. A center part wider than the outer peripheral part formed at a position close to the center point;
The electrodeless region is formed between the outer peripheral portion and the central portion, and is substantially L-shaped formed along one or more corners of the base bottom surface and two or more sides in contact with the corners. 2. A base for an electronic component package according to claim 1 , wherein said base has a substantially U-shaped notch, and a bump is formed in said central portion . The terminal electrode includes a belt-like outer peripheral portion extending in a state of being close to one or more corners of the base bottom surface and two or more sides in contact with the corner, and a base bottom surface from the outer peripheral portion via a bent portion. 2. A base for an electronic component package according to claim 1, wherein a bump is formed in the central portion. . An electronic component package comprising: a base for an electronic component package according to claim 1; and a lid for hermetically sealing the electronic component element.

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