Patent Application
20110228505
1. Technical Field
The present invention relates to a package used for housing a resonator element and a semiconductor device, an electronic device configured by using the package, and a method of manufacturing an electronic device, and more particularly, to a package of a type that horizontally mounts a resonator element and a semiconductor device for the purpose of reducing the height thereof, an electronic device using the package, and a method of manufacturing an electronic device.
2. Related Art
Electronic devices that are represented by a crystal oscillator, an SAW filter, or the like include a resonator in which excitation is formed and a semiconductor integrated circuit (semiconductor device) having an oscillation circuit used for oscillating the resonator as its major configurations.
As electronic devices having such a configuration, various types having different dispositional forms of constituent elements according to the purpose of decreasing the mounting area or reducing the height are being developed. For example, in electronic devices of which the major purpose is to decrease the mounting area, a form in which a piezoelectric device and a semiconductor device are disposed in the vertical direction is frequently employed. On the other hand, in electronic devices of which the major purpose is to reduce the height, a form in which a piezoelectric device and a semiconductor device are horizontally disposed is frequently employed. In such electronic devices, even in a case where any of the dispositional forms is employed, after a resonator is configured by mounting and sealing a resonator element, the electrical characteristics of the resonator, such as the resonant frequency and the CI value are tested, and the electrical characteristics are adjusted as necessary. In order to satisfy such a request, in electronic devices, a monitoring electrode terminal that is used for detecting the vibration characteristics that are unique to the resonator is disposed. Such a monitoring electrode terminal is generally disposed on a side face of the package configuring the electronic device. However, disposition of the terminal on the side face of the package becomes a factor that hinders miniaturization or height reduction of the electronic device, and thus development of various technologies is continuing.
For example, a technology disclosed in JF-A-2005-223640, as shown in
In addition, a technology disclosed in JP-A-2009-27465, as shown in
In addition, a technology disclosed in JP-A-2008-301196 employs a form as shown in
In the technologies described above, structures appropriate for each of the purposes of miniaturization and reducing the height are formed with focusing on the disposition location or the use form of the monitoring electrode terminal. However, the technology disclosed in JP-A-2005-223640 relates to a structure that is not appropriate for reducing the height, which is regarded as an object of the invention. In addition, according to the technology disclosed in JP-A-2009-27465, the monitoring electrode terminal is disposed on the primary face on the side on which the resonator and the semiconductor device are mounted. Thus, when the vibration characteristics are adjusted, the probe is not brought into contact with the monitoring electrode terminal from the rear face side of the base substrate. Accordingly, in order to adjust the vibration characteristics, a dedicated holder having a terminal is necessary. Furthermore, according to the technology disclosed in JP-A-2008-301196, the monitoring electrode terminal is configured to be disposed on the same primary face as the external terminal disposing face for mounting. Thus, a sufficient area with which the probe can be brought into contact may not be secured, so that a case where the package is miniaturized cannot be responded.
An advantage of some aspects of the invention is that it provides a package which is appropriate for reducing the height and in which a probe contact surface can be reliably secured even in a case where the package is miniaturized, an electronic device using the package, and a method of manufacturing an electronic device.
The invention can be implemented as the following forms or application examples.
According to this application example, there is provided a package having a base substrate in which an area, in which a resonator element is mounted, and an area, in which a semiconductor device is mounted, are disposed so as to be aligned in a horizontal direction. The package includes on one face of the base substrate: a resonator element mounting pad that is used for mounting the resonator element; a first semiconductor device connecting pad that is electrically connected to the resonator element mounting pad; a second semiconductor device connecting pad that is electrically connected to a mounting terminal formed on the other face of the base substrate; and a cutting pattern that electrically connects the first semiconductor device connecting pad and the second semiconductor device connecting pad.
By having such characteristics, a package that is appropriate for reducing the height of the electronic device can be implemented. In addition, the mounting terminal (external mounting terminal) is used as a so-called monitoring electrode terminal. Thus, even in a case where the package is miniaturized, the probe contact surface can be reliably secured.
According to this application example, there is provided an electronic device in which a resonator element and a semiconductor device are mounted in the package according to the application example 1, wherein the cutting pattern is cut off.
According to the electronic device having such a configuration, after the cutting pattern of the package is cut off, there is no path directly connecting to the resonator element mounting pad from the external terminal, and the external terminal is responsible for a unique function.
The electronic device according to the application example 2 may be configured such that a concave dent portion is included at a cutting position of the cutting pattern in the base substrate.
According to the electronic device having such characteristics, cutting of the cutting pattern can be reliably performed.
According to this application example, there is provided a method of manufacturing an electronic device. The method includes: mounting a resonator element on the resonator element mounting pad of the package according to Application 1; adjusting oscillation and a resonant frequency of the resonator element through the mounting terminal; and cutting the cutting pattern after the adjusting of oscillation and a resonant frequency of the resonator element.
By having such characteristics, the frequency can be adjusted from one face side of the base substrate while detecting the vibration characteristics by bringing the probe into contact from the other face side of the base substrate.
The method of manufacturing an electronic device according to the application example 4 may be configured such that in the cutting of the cutting pattern, a cutting mark that allows a surface of the base substrate of the package to be concavely dented remains.
By cutting the cutting pattern using such a method, the cutting of the cutting pattern can be reliably performed.
The invention will be described with reference to the accompanying drawings, wherein like numbers reference like elements.
Hereinafter, a package, an electronic device, and a method of manufacturing an electronic device according to embodiments of the invention will be described in detail with reference to drawings.
The electronic device 10 according to this embodiment is basically configured by a resonator element 110, an IC chip 114 as a semiconductor device, and a package 11.
As the resonator element 110, a quartz crystal resonator element such as an AT cut quartz crystal resonator element can be used. In addition, the resonator element 110 may be a tuning fork-type quartz crystal resonator element, a surface acoustic wave crystal resonator element, or the like, that has a different cut angle of a crystal element plate or form of main oscillation. As the material of the main resonator element, lithium tantalate, lithium niobate, or the like other than crystal may be used. Furthermore, instead of the quartz crystal resonator element, various types of resonator elements other than a piezoelectric resonator element can be used. For example, even in a case where an MEMS (Micro Electro Mechanical Systems) resonator element that is formed by processing a silicon substrate or the like is used, the electronic device 10 according to this embodiment can be configured.
As the IC chip 114, an integrated circuit that is configured by a semiconductor device having a circuit structure for oscillating a resonator (a piezoelectric resonator in a case where a piezoelectric element plate is mounted as the resonator element 110) or the like may be used. In the IC chip 114, a plurality of electrode pads (not shown in the figure) is disposed.
The package 11 is basically configured by a base substrate 12 and a lid body 112 that is used for configuring a resonator by sealing a resonator element 110 mounted on the base substrate 12. The base substrate 12 according to this embodiment is configured by stacking the first substrate 14, the second substrate 16, and the third substrate 18. The constituent materials of the substrates are formed from a ceramic materials such as an alumina ceramic, glass ceramic, or the like, and the substrates are integrated together by being stacked and sintered using a green sheet method. In the second substrate 16 and the third substrate 18, metal patterns are formed. Thus, in
The first substrate 14 is the uppermost layer of the substrates configuring the base substrate 12 and is a frame body that forms the first concave portion 20 and the second concave portion 22 that surround the outer periphery of the resonator element 110 and the IC chip 114. The first concave portion 20 forms an internal space that houses the resonator element 110 therein. In addition, the second concave portion 22 forms a space that houses the IC chip 114 therein. The first substrate 14 is formed so as to have a thickness that is at least larger than that of the resonator element 110. The reason for this is to enable the first concave portion 20 to be sealed by using the lid body 112, to be described in detail later, after housing the resonator element 110 in the first concave portion 20.
The second substrate 16 is an intermediate layer of the substrates configuring the base substrate 12 and, on the first primary face that is a face bonded to the above-described first substrate 14, has metal patterns and via holes that are used for laying down the metal patterns formed on the first primary face to the second primary face that is positioned on the side of the rear face of the first primary face. As the metal patterns formed on the first primary face, there are resonator element mounting pads 24 that are used for mounting the resonator elements 110, IC chip mounting pads 30 that are used for mounting the IC chips 114, and connection patterns 56, 58, 60, 61, 62, and 64 that electrically connect the metal patterns and the via holes. In the second substrate 16 according to this embodiment, there are the first resonator element mounting pad 26 and the second resonator element mounting pad 28 as the resonator element mounting pads 24. In addition, as the IC chip mounting pads 30, a GND pad 32, a fout pad 34, the first resonator element connecting pad 36 (the first semiconductor device connecting pad), the second resonator element connecting pad 38 (the first semiconductor device connecting pad), a Vc pad 40 (the second semiconductor device connecting pad), a Vdd pad 42 (the second semiconductor connecting pad), and the like are included.
In addition, as the via holes, the first via hole 44 to the sixth via holes 54 are included. From among the via holes, the first via hole 44 is disposed right below the first resonator element mounting pad 26. In addition, the second via hole 46 is disposed between the GND pad 32 and the first resonator element connecting pad and is connected to the GND pad 32 through the connection pattern 58. The third via hole 48 is disposed between the fout pad 34 and a corner portion close to the fout pad 34 and is connected to the fout pad 34 through the connection pattern 60. The fourth via hole 50 is disposed in a tip end position of the connection pattern that is disposed so as to extend from the first resonator element connecting pad 36 to the side of the resonator element mounting position. In addition, the fifth via hole 52 is disposed at a position that is in the point symmetry with the first resonator element connecting pad 36 with respect to the Vc pad 40 as the base point and is connected to the Vc pad 40 through the connection pattern 62. Furthermore, the sixth via hole is disposed at a position that is in the point symmetry with the second resonator element connecting pad 38 with respect to the Vdd pad 42 as the base point and is connected to the Vdd pad 42 through the connection pattern 64.
The second substrate 16 that configures the package of the electronic device 10 according to this embodiment has cutting patterns 66 and 68 that electrically connect the first resonator element connecting pad 36 and the Vc pad 40 and the second resonator element connecting pad 38 and the Vdd pad 42, respectively.
The third substrate 18 is a lowermost layer of the substrates configuring the base substrate 12 and has the first primary face bonded to the second substrate 16 and the second primary face that is exposed to the outside of the package. On the four corners of the third substrate 18, notches are formed, and the first to fourth castellations 82 to 88 are formed. On the first primary face of the third substrate 18, via hole correspondence pads and connection patterns corresponding to lay-down positions of the via holes of the second substrate 16 are formed. As the via hole correspondence pads, there are the first via hole correspondence pad 70 to the sixth via hole correspondence pad 80, which are formed so as to be disposed at positions corresponding to the first via hole 44 to the sixth via hole 54.
The first via hole correspondence pad 70 and the fourth via hole correspondence pad 76 are connected to each other through a connection pattern 90. Accordingly, the first resonator element mounting pad 26 and the first resonator element connecting pad 36 are electrically connected to each other. In addition, the second via hole correspondence pad 72 is connected to the third castellation 86 through a connection pattern 92. The third via hole correspondence pad 74 is connected to the second castellation 84 through a connection pattern 94. The fifth via hole correspondence pad 78 is connected to the fourth castellation 88 through a connection pattern 96. In addition, the sixth via hole correspondence pad 80 is connected to the first castellation 82 through a connection pattern 98.
On the second primary face of the third substrate 18, four external mounting terminals are formed. Each of the four external mounting terminals is connected to one of the first to fourth castellations 82 to 88 formed on the four corners of the third substrate 18. The four external mounting terminals configure a GND terminal 104, an Lout terminal 102, a Vc terminal 106, and a Vdd terminal 100 in accordance with the attributes of pads (the GND pad 32, the Lout pad 34, the Vc pad 40, and the Vdd pad 42) that are electrically connected thereto through the castellations and the connection electrodes.
The lid body 112 is a member that covers an upper opening portion of the first concave portion 20 of the first substrate 14. The lid body 112 may be formed to have a flat plate shape or a cap shape taken along the outer periphery of the first concave portion 20, that is, a shape that covers the first concave portion 20 in a convex shape. In this embodiment, as an example of the lid body 112, a plate-shaped metal lid is used. In addition, for joining the lid body 112 and the first substrate 14, a metal brazing material such as a seam ring, a brazing material such as low melting point glass, or the like, which is not shown in the figure, may be used.
In the package 11, which has the above-described configuration, according to this embodiment, in a state in which the cutting patterns 66 and 68 are not cut off, the Vc terminal 106 and the first resonator element mounting pad 26 are electrically connected, and the Vdd terminal 100 and the second resonator element mounting pad 28 are electrically connected. Accordingly, the Vc terminal 106 and the Vdd terminal 100 serve as monitoring electrode terminals. On the other hand, after the cutting patterns 66 and 68 are cut off, the first resonator element connecting pad 36 and the Vc pad 40 are electrically separated from each other, and the second resonator element connecting pad 38 and the Vdd pad 42 are electrically separated from each other. Accordingly, the Vc terminal 106 and the Vdd terminal 100 respectively become terminals responsible for unique functions. Therefore, the vibration characteristics of the resonator element 110 cannot be directly detected from the outside (the side of the external mounting terminal forming face) of the package 11.
The resonator element 110 is mounted in the first resonator element mounting pad 26 and the second resonator element mounting pad 28 through a conductive bonding agent or the like. Accordingly, the first resonator element connecting pad 36 and the second resonator element connecting pad 38 are electrically connected to excitation electrodes, not shown in the figure, of the resonator element 110. Here, in a case where a surface acoustic wave crystal resonator element or the like is used as the resonator element 110, a technique such as wire bonding may be used instead of mounting through the conductive bonding agent.
The IC chip 114 is mounted in the IC chip mounting pads 30 (the GND pad 32, the fout pad 34, the first resonator element connecting pad 36, the second resonator element connecting pad 38, the Vc pad 40, and the Vdd pad 42) disposed in the second concave portion 22 through a metal bump or the like using flip-chip bonding. Accordingly, the first resonator element connecting pad 36, the second resonator element connecting pad 38, the fout pad 34, and the Vdd pad 42 are connected through the IC chip 114, and thus the resonator element 110 oscillates based on the operation conditions recorded in the IC chip 114.
In the outer periphery of the IC chip 114, in the internal area of the second concave portion 22 in which the IC chip 114 is mounted, a resin member 116 is filled up. By filling up with the resin member 116, deterioration of the vibration characteristics due to the attachment of moisture to the IC chip 114 mounting face or formation of a short circuit due to the attachment of dust, and the like can be prevented. Accordingly, the resin member 116 having an insulating property is used. As an example, a general mold resin can be used.
Next, a method of manufacturing the electronic device having the above-described configuration will be described with reference to
First, from among the first substrate 14, the second substrate 16, and the third substrate 18 of the bases substrate 12, metal patterns are formed on the second substrate 16 and the third substrate 18. The formation of the metal patterns is performed by using a technique such as screen printing, and the second and third substrates 16 and 18 are integrated as one body by being sintered with the first substrate 14 (base substrate manufacturing process: S100). Then, after the sintering process, a plating process is performed for the metal patterns so as to form a nickel layer and a gold layer.
The first resonator element mounting pad 26 and the second resonator element mounting pad 28 disposed in the first concave portion 20 of the formed base substrate 12 are coated with a conductive bonding agent. A resonator element 110 is mounted on the first resonator element mounting pad 26 and the second resonator element mounting pad 28 that are coated with the conductive bonding agent, whereby mounting of the resonator element 110 is performed (resonator element mounting process: S110).
Then, the base substrate 12 on which the resonator element 110 is mounted is set in a holder 150 as shown in
Then, the characteristics of the resonator element 110 such as the resonant frequency and the like are detected by bringing the probe 162 of the characteristic test device 160 into contact with the Vc terminal 106 and the Vdd terminal 100, and the resonant frequency is adjusted by emitting laser beams to the excitation electrode of the resonator element 110 through the opening portion 152 of the holder 150 (frequency adjusting process: S120).
After the frequency adjusting process is completed, the upper opening portion of the first concave portion 20 is sealed with the lid body 112. For the bonding of the lid body 112, seam welding using a seam ring not shown in the figure, a liquid phase diffusion bonding method using a metal-based brazing material, or the like can be used. By sealing the first concave portion 20 with the lid body 112, a resonator is configured. By sealing the first concave portion 20 before a pattern cutting process to be described in detail later, deterioration of the vibration characteristics due to the attachment of dust generated by cutting the cutting patterns 66 and 68 to the resonator element 110 can be prevented (sealing process: S130).
After completion of the frequency adjusting process, the base substrate 12 on which the resonator element 110 is mounted is detached from the holder 150, and the cutting patterns 66 and 68 are cut. The cutting of the cutting patterns 66 and 68 can be performed by emitting laser beams such as Nd-YAG laser beams or Nd-YVO4 laser beams. The cutting mark 16a of the cutting patterns 66 and 68 cut off by the laser beams, as shown in
The emitting of the laser beams may be performed once or a plurality of times. In a case where the laser beams are emitted a plurality of times, the width of the cut portion can be increased by displacing the emitting position along the wiring direction of the cutting patterns 66 and 68. In addition, in a case where the laser beams are emitted a plurality of times, it is preferable that the laser beams are emitted while dust generated by the emission of the laser beams is sucked and eliminated. The reason for this is that there is a possibility that the cutting patterns 66 and 68 are hindered from being electrically cut off due to the attachment of dust which includes metal patterns generated by emission of the laser beams performed a plurality of times to a place where the cutting mark 16a cut off by the laser beams remains (pattern cutting process: S140).
After the pattern cutting process, an IC chip 114 is mounted in the second concave portion 22. The IC chip 114 is mounted by flip-chip bonding through a gold bump or the like (IC chip mounting process: S150). After the IC chip 114 is mounted, a resin member 116 is filled in a gap portion of the second concave portion 22 and is solidified (resin filling process: S160).
According to the electronic device 10 formed as above, a configuration in which the resonator element 110 and the IC chip 114 are disposed in the horizontal direction that can be regarded as being appropriate for reducing the height thereof is formed. In addition, in testing or adjusting the vibration characteristics of the resonator element 110, by using the external mounting terminal as a monitoring electrode terminal, the area with which the probe 162 is brought into contact can be reliably secured even in a case where the electronic device is miniaturized. Furthermore, since the external mounting terminal is used as the monitoring electrode terminal, the probe 162 can be brought into contact with the monitoring electrode terminal from the rear face side in a state in which the base substrate 12, on which the resonator element 110 is mounted, is set in the holder 150. Accordingly, the resonant frequency can be adjusted while detecting the vibration characteristics and the like.
In the above-described embodiment, the pattern widths of the cutting patterns 66 and 68 are represented to be the same as the pattern widths of the other metal patterns in the figure. However, as shown in
In addition, in the package according to the above-described embodiment, as shown in
In addition, for easy understanding of the description, the electronic device 10 shown in
The entire disclosure of Japanese Patent Application No. 2010-063874, filed Mar. 19, 2010 is expressly incorporated by reference herein.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2010-063874 | Mar 2010 | JP | national |
