Oscillator and manufacturing method

Abstract

Oscillator and manufacturing method. When an IC and a package are bonded via an FCB, there is a problem that the performance of the IC may deteriorate. The oscillator comprises: a package having a plurality of external terminals provided on a mounting surface; a circuit element housed in the package; and an oscillator housed in the package and electrically connected to the circuit element. The circuit element is electrically connected to the package via a plurality of pads, each of which is bonded to the package via a bump component. The circuit element overlaps with at least one of the plurality of external terminals when viewed from above, and each of the bump components is bonded to the package at a position where at least a portion does not overlap with the plurality of external terminals when viewed from above.

Description

Technical Field

[0001] The present invention relates to an oscillator and a method of manufacturing the same. Background Art

[0002] There are oscillators with a structure in which an IC is mounted on a package made of a material such as ceramic using an FCB (flip chip bonding) process. Patent Document 1 discloses an oscillator with such a structure, in which the external terminals and the pads of the IC do not overlap when viewed from above.

[0003] Patent Document 1: Japanese Patent Application Laid-Open No. 2011-055033

[0004] When miniaturizing the oscillator having the structure described in Patent Document 1, the distance between the external terminals of the package becomes narrower. Simply narrowing the distance between the external terminals can lead to the IC pads partially overlapping the external terminals in a plan view.

[0005] However, in oscillators, the package thickness differs depending on whether external terminals are present on the backside or absent. Consequently, differences in height occur at the mounting locations of the IC's multiple pads on the package's IC mounting surface. This creates a problem: when the IC and package are bonded using an FCB, the pressure applied during bonding can vary across the IC's multiple pads, potentially degrading IC performance. Summary of the Invention

[0006] An oscillator for solving the above-mentioned problem comprises: a package having a plurality of external terminals on a mounting surface; a circuit element housed in the package; and an oscillator housed in the package and electrically connected to the circuit element, the circuit element being electrically connected to the package via a plurality of solder pads, the plurality of solder pads being respectively joined to the package via bump components, the circuit element overlapping with at least one of the plurality of external terminals when viewed from above, and the bump components being respectively joined to the package at positions where at least a portion does not overlap with the plurality of external terminals when viewed from above. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 is a perspective top view of the oscillator.

[0008] Figure 2 is a cross-sectional view of the oscillator.

[0009] Figure 3 This is a top view of the IC configuration surface.

[0010] Figure 4 It is a diagram illustrating the structure of an oscillator of a comparative example.

[0011] Figure 5It is a diagram showing a state of IC bonding in a comparative example.

[0012] Figure 6 is a perspective top view of the oscillator.

[0013] Figure 7 is a perspective top view of the oscillator.

[0014] Figure 8 is a perspective top view of the oscillator.

[0015] Description of labels

[0016] 1: Oscillator; 1a: Oscillator; 1b: Oscillator; 2: Oscillator; 10: Container; 11: Substrate; 11a: Surface 1; 11b: Surface 2; 11c: IC placement surface; 12: Frame 1; 13: Frame 2; 14: Seam ring; 15: Package; 16: Cover; 20: Oscillator; 41a-41b: Connection wiring; 42a-42f: Connection wiring; 421a: Part 1; 422a: Part 2; 421d: Part 3; 422d: Part 4; 421e: Part 5; 422e: Part 6; 421f: Part 7; 42 2f: Part 8; 43a~43b: Through hole; 44a~44d: External terminal; 45a~45b: Bump component; 46a~46f: Bump component; 50: IC; 51a~51f: Pad; 61: 1st side; 62: 2nd side; 63: 3rd side; 64: 4th side; 65: 5th side; 66: 6th side; 67: 7th side; 68: 8th side; 71: IC configuration surface; 72a~72d: External terminal; 73a~73f: Bump component; 74a~74f: Connection wiring; 75: Package; 80: IC; 81a~81f: Pad. DETAILED DESCRIPTION

[0017] Here, embodiments of the present invention will be described in the following order.

[0018] (1) First embodiment:

[0019] (1-1) Oscillator structure:

[0020] (1-2) Oscillator manufacturing method:

[0021] (2) Second embodiment:

[0022] (2-1) Oscillator structure:

[0023] (2-2) Oscillator manufacturing method:

[0024] (3) The third embodiment:

[0025] (4) Other implementation methods:

[0026] (1) First embodiment:

[0027] (1-1) Oscillator structure:

[0028] use Figure 1 、 2 The structure of the oscillator 1 of the first embodiment is described. For the sake of convenience, it is assumed that the oscillator 1 is arranged on an XYZ coordinate system consisting of three axes that are orthogonal to each other, namely the X-axis, the Y-axis, and the Z-axis. The oscillator 1 is arranged in a manner such that the height direction is parallel to the Z-axis, with the surface for connection to the external substrate, namely the mounting surface, being the bottom. The oscillator 1 is rectangular when viewed from above, and is arranged in a manner such that the long side direction of the rectangle is parallel to the X-axis and the short side direction is parallel to the Y-axis. On the X-axis, the tip side of the arrow is set to the right or right side, and the base side is set to the left or left side. On the Y-axis, the tip side of the arrow is set to the back side, and the base side is called the front. On the Z-axis, the tip side of the arrow is called the top, and the base side is called the bottom or bottom.

[0029] Figure 1 This is a perspective top view of the oscillator 1. Hereinafter, a top view of an object viewed from above is referred to as a top view. Figure 2 yes Figure 1 A cross-sectional view of the oscillator 1 taken along line AA is shown.

[0030] The oscillator 1 of this embodiment includes a container 10 , a vibrator 20 , and an IC 50 .

[0031] The container 10 includes a package 15 and a lid 16. The package 15 is a housing that houses the vibrator 20 and the IC 50. The lid 16 is a metal cover that covers the upper surface of the package 15. Figure 1 The top view is a top view of the oscillator 1 with the cover 16 seen through.

[0032] like Figure 1 As shown, in a plan view, the package 15 is rectangular having a first side 61 as the left end side, a second side 62 opposite to the first side 61 , a third side 63 as the back end side, and a fourth side 64 opposite to the third side 63 .

[0033] The vibrator 20 is a vibrating piece using a quartz substrate as a piezoelectric body.

[0034] The IC 50 is a rectangular plate-shaped integrated circuit element (Integrated Circuit), and has a plurality of pads 51a to 51f on one surface for electrical connection to the package 15. Hereinafter, the pads 51a to 51f will be collectively referred to as pads 51 as appropriate.

[0035] like Figure 1As shown, when viewed from above, IC50 is rectangular having a left end side parallel to the first side 61, namely the fifth side 65, a sixth side 66 which is the opposite side of the fifth side 65 and farther away from the first side 61 than the fifth side 65, a seventh side 67 which is the end side on the inner side, and an eighth side 68 which is the opposite side of the seventh side 67.

[0036] The distance between the first side 61 and the fifth side 65 (the distance in the X-axis direction) is greater than the distance between the second side 62 and the sixth side 66 .

[0037] Pad 51a is a power supply pad to which a power supply voltage is applied. Pad 51b is a first vibrator pad electrically connected to vibrator 20. Pad 51c is a second vibrator pad electrically connected to vibrator 20. Pad 51d is a control pad to which an output control signal of a clock signal is input.

[0038] The pad 51e is a ground pad to which a ground potential is supplied, and the pad 51f is an output pad to which a clock signal is output.

[0039] Furthermore, the pad group of pads 51a to 51d is arranged along the fifth side 65 closer to the fifth side 65 than to the sixth side 66. The pad group arranged along the fifth side 65 closer to the fifth side 65 than to the sixth side 66 is referred to as the first pad group. Pads 51a to 51d are arranged at the same position in the X-axis direction. However, each pad 51 of the first pad group may be arranged at a different position in the X-axis direction. Furthermore, some pads in the first pad group may be arranged at the same position in the X-axis direction.

[0040] Furthermore, the pad group of pads 51e to 51f is arranged along the sixth side 66, closer to the sixth side 66 than to the fifth side 65. The pad group arranged along the sixth side 66, closer to the sixth side 66 than to the fifth side 65, is referred to as the second pad group. Pads 51e to 51f are arranged at the same position in the X-axis direction. However, each pad 51 of the second pad group may be arranged at a different position in the X-axis direction. Furthermore, some pads in the second pad group may be arranged at the same position in the X-axis direction.

[0041] In this embodiment, the distance between the sixth side 66 and the second pad group on the X axis is greater than the distance between the fifth side 65 and the first pad group on the X axis. That is, the second pad group is arranged closer to the center of the IC 50 than the first pad group in the X axis direction.

[0042] like Figure 1 、 2As shown, package 15 includes a substrate 11 forming its bottom, a first frame 12 forming a housing space for IC 50 and a support base for vibrator 20, a second frame 13 forming a housing space for vibrator 20, and a seam ring 14 serving as a bonding material for connecting to lid 16. Package 15 also includes a plurality of connection wires 41a and 41b for connecting to vibrator 20, a plurality of connection wires 42a to 42f for connecting to IC 50, a through-hole 43a for connecting connection wires 41a and 42b, a through-hole 43b (not shown) for connecting connection wires 41b and 42c, and a plurality of external terminals 44a to 44d for connecting to an external substrate. Hereinafter, connection wires 41a and 41b will be collectively referred to as connection wires 41. Furthermore, connection wires 42a to 42f will be collectively referred to as connection wires 42. Furthermore, through-holes 43a and 43b will be collectively referred to as through-holes 43. In addition, below, the external terminals 44a to 44d are collectively referred to as the external terminals 44 as needed.

[0043] The connection wirings 41a, 41b and the vibrator 20 are bonded via the bump members 45a, 45b, respectively. Figure 2 As shown, bump component 45a is located between connection wiring 41a and vibrator 20. Similarly, bump component 45b is located between connection wiring 41b and vibrator 20. Hereinafter, bump components 45a and 45b will be collectively referred to as bump component 45. Connection wiring 42a to 42f and pads 51a to 51f of IC 50 are bonded via bump components 46a to 46f, respectively. Hereinafter, bump components 46a and 46b will be collectively referred to as bump component 46.

[0044] The substrate 11 has a front surface as a first surface 11a and a back surface as a second surface 11b. In this embodiment, the substrate 11 is a ceramic substrate. The substrate 11 may also be made of an insulating substrate material such as glass or resin, or a composite of these.

[0045] External terminals 44a to 44d are located at the four corners of the bottom surface of substrate 11, or second surface 11b. When viewed from above, external terminals 44a to 44d are located at the upper left, lower left, upper right, and lower right corners of second surface 11b, respectively. Each of external terminals 44a to 44d is a metal component having a plate-shaped portion whose surface is parallel to the XY plane, and a portion extending in the height direction from the corner of second surface 11b to connect to connection wiring 42. When viewed from above, external terminals 44a, 44c, and 44d each have a shape that includes a rectangular region and an area connecting this region to the corner of second surface 11b. When viewed from above, external terminal 44b has a shape that includes a rectangular region with a corner cut off near the center of second surface 11b and an area connecting this region to the corner of second surface 11b. Thus, among external terminals 44a to 44d, the shape of external terminal 44b when viewed from above differs from that of the other external terminals. This allows the user to visually identify which terminal each of the external terminals 44a to 44d is. However, as long as one of the external terminals 44a to 44d has a shape that is distinguishable from the others, the external terminals 44a to 44d may have other shapes.

[0046] In the present embodiment, the pads 51 are arranged so as not to overlap at all with any of the external terminals 44 in the oscillator 1 in a plan view.

[0047] Furthermore, in this embodiment, the oscillator 1 uses a miniaturized package 15. Consequently, the proportion of the second surface 11b occupied by the external terminals 44 increases compared to a case where a non-miniaturized package 15 is used. Consequently, when viewed from above, the IC 50 and the external terminals 44c and 44d overlap. However, the IC 50 may be configured so that a portion overlaps with at least one of the external terminals 44 when viewed from above, or other configurations may be employed.

[0048] External terminals 44a and 44b are provided along first side 61, closer to first side 61 than to second side 62. External terminal 44a is a terminal supplied with a power supply voltage, i.e., a power terminal. External terminal 44b is a control terminal to which a signal for controlling the on / off switching of a clock signal is applied. External terminals 44c and 44d are provided along second side 62, closer to second side 62 than to first side 61. External terminal 44c is a terminal for outputting a clock signal, i.e., an output terminal. External terminal 44d is a ground terminal supplied with a ground potential.

[0049] A first frame body 12 and a second frame body 13, both of which are frame-shaped, are stacked on the substrate 11. The inner wall of the left portion of the first frame body 12 protrudes to the right relative to the inner wall of the left portion of the second frame body 13, forming a step. Here, the term "frame-shaped" refers to a frame-shaped portion that encloses a rectangular parallelepiped space. Below, the portion of the first surface 11a surrounded by the inner wall of the first frame body 12 and on which the IC 50 is disposed is referred to as the IC placement surface 11c. The distance between the first side 61 and the fifth side 65 is greater than the distance between the second side 62 and the sixth side 66. Therefore, when viewed from above, the IC placement surface 11c is positioned to the right on the X-axis. Furthermore, the external terminals 44 are disposed at the four corners of the second surface 11b. Therefore, the distance between the second pad group and the external terminals 44 (44c, 44d) on the right is shorter than the distance between the first pad group and the external terminals 44 (44a, 44b) on the left. Therefore, the second pad group is more likely to overlap with external terminals 44 than the first pad group. Connecting wires 42a to 42f are arranged on IC placement surface 11c. Connecting wires 42a to 42f are plate-shaped metal components used to connect to pads 51a to 51f. Connecting wires 42a, 42d, 42e, and 42f each have a shape formed by combining two elongated sections when viewed from above on IC placement surface 11c. Furthermore, connecting wires 42b and 42c each have a rectangular shape when viewed from above on IC placement surface 11c. Figure 3 The connecting wiring 42 and the pad 51 arranged on the IC arrangement surface 11 c are shown.

[0050] In this embodiment, the connection wiring 42a is a wiring, namely, a power supply wiring, electrically connected to the power supply pad, namely, the pad 51a. The connection wiring 42a includes a first portion 421a extending rightward from the upper left corner of the IC placement surface 11c when viewed from above, and a second portion 422a extending forward from the right end of the first portion 421a when viewed from above. The first portion 421a is used to connect the power supply pad, namely, the pad 51a, to the power supply terminal, namely, the external terminal 44a. Furthermore, the second portion 422a is provided so as to extend between the output pad, namely, the pad 51e, and the first oscillator pad, namely, the pad 51b, when viewed from above.

[0051] Furthermore, the connecting wiring 42d is a control wiring that is electrically connected to the control pad, or pad 51d. The connecting wiring 42d includes a third portion 421d extending rightward from the lower left corner of the IC placement surface 11c when viewed from above, and a fourth portion 422d extending inward from the right end of the third portion. The third portion 421d is used to connect the control pad, or pad 51d, to the control terminal, or external terminal 44b. Furthermore, the fourth portion 422d is provided so as to extend between the ground pad, or pad 51f, and the second oscillator pad, or pad 51c, when viewed from above.

[0052] Furthermore, connecting wiring 42b and 42c include rectangular portions connected to first oscillator pad 51b and second oscillator pad 51c, respectively, and extending rightward from the left end of IC placement surface 11c when viewed from above. Furthermore, connecting wiring 42e includes a fifth portion 421e connected to output pad 51e and extending leftward from the upper right corner of IC placement surface 11c when viewed from above, and a sixth portion 422e extending near the front from the left end of fifth portion 421e when viewed from above. Furthermore, connecting wiring 42f includes a seventh portion 421f connected to ground pad 51f and extending leftward from the lower right corner of IC placement surface 11c when viewed from above, and an eighth portion 422f extending inward from the left end of seventh portion 421f when viewed from above.

[0053] IC 50 is arranged on IC placement surface 11c so that the surface having pads 51 faces IC placement surface 11c. Pads 51a to 51f overlap connection wirings 42a to 42f, respectively, when viewed from above. Pads 51a to 51f and connection wirings 42a to 42f are flip-chip bonded together using bumps 46a to 46f, bonding members made of a conductive material such as solder. Pads 51 are arranged so that they do not overlap external terminals 44 when viewed from above. Therefore, bumps 46 are bonded to package 15 at positions that do not overlap external terminals 44 when viewed from above.

[0054] The stepped portion formed by the first frame body 12, that is, the portion of the upper surface of the first frame body 12 surrounded by the inner wall of the second frame body 13, functions as a support base for the vibrator 20. Hereinafter, this portion is referred to as the vibrator support surface. A plurality of connection wires 41a and 41b for connecting to the vibrator 20 are arranged at the location where the vibrator 20 is arranged on the vibrator support surface.

[0055] The vibrator 20 is electrically connected to the connecting wires 41a and 41b via bump members 45a and 45b, which are bonding members made of a conductive material such as solder, and is fixed to the vibrator support surface. The connecting wires 41a and 41b are electrically connected to the connecting wires 42b and 42c, respectively, via a through hole 43a and a through hole 43b (not shown) extending downward through the interior of the first frame body 12.

[0056] Thus, the resonator 20 and the IC 50 are housed in a space surrounded by the frame-shaped first and second frames 12 and 13 with the IC placement surface 11c as the bottom.

[0057] In a preferred embodiment, lid 16 is made of Kovar (Fe-Ni-Co alloy), and seam ring 14 is made of silver solder. The storage space within package 15 is sealed by lid 16 in an inert gas atmosphere such as nitrogen, helium, or argon, or in a reduced-pressure environment below atmospheric pressure. This protects the IC 50, resonator 20, and other components housed within the space from impact, dust, heat, moisture, and other influences. Furthermore, metal lid 16 is connected to ground potential.

[0058] Here, use Figure 4 An oscillator 2 according to a hypothetical comparative example will be described. Figure 4 1 and 2 are diagrams for explaining the positional relationship between the pads 81 a to 81 f of the IC 80 and the external terminals 72 a to 72 d in the oscillator 2 . Figure 4 The oscillator 2 is shown in plan view as pads 81a to 81f and external terminals 72a to 72d. Hereinafter, the pads 81a to 81f are collectively referred to as pads 81 as appropriate. The external terminals 72a to 72d are collectively referred to as external terminals 72 as appropriate.

[0059] like Figure 4 As shown, in the oscillator 2 of the comparative example, pads 81a to 81d, like pads 51a to 51d, do not overlap with any external terminal 72 in a plan view. On the other hand, pads 81e and 81f overlap with external terminals 72c and 72d, respectively, in a plan view.

[0060] Due to the placement of external terminals 72 on the mounting surface of oscillator 2, the Z-axis thickness of the package substrate on IC placement surface 71 of oscillator 2 differs between the area on the back surface where external terminals 72 are located and the area where external terminals 72 are not located. Consequently, a height difference occurs on IC placement surface 71 between the area that overlaps with external terminals 72 and the area that does not overlap with external terminals 72 when viewed from above. Consequently, a height difference occurs at the locations on IC placement surface 71 where pads 81a to 81f are located.

[0061] When mounting an IC in a package, the following process is performed. First, identically shaped bump components are bonded to the IC's pads. Then, the IC's surface with the pads is aligned with the top of the package, with the package's mounting surface and the IC's surface parallel. In this state, the IC is brought close to the package's IC placement surface. When the bumps on the IC's pads come into contact with the wiring on the IC placement surface, a load and ultrasonic waves are applied between the pads and the wiring, bonding the bump components and wiring.

[0062] When IC 80 is mounted on package 75 of oscillator 2 through the above operation, the following situation occurs. Specifically, IC 80, with bump components 73a to 73f provided on pads 81a to 81f, approaches IC placement surface 71 of package 75. Hereinafter, bump components 73a to 73f will be collectively referred to as bump components 73, as appropriate. Initially, bump components 73e and 73f on pads 81e and 81f come into contact with connection wirings 74e and 74f on IC placement surface 71 before bump components 73a to 73d on pads 81a to 81d. Figure 5 The following figure shows the situation in this case. Then, while maintaining the surface of IC 80 and the mounting surface of package 75 parallel, IC 80 and package 75 are brought closer together. After all of the bump components 73a to 73f and the connecting wirings 74a to 74f on pads 81a to 81f are in contact, a load and ultrasonic waves are applied to the pads 81a to 81f to bond IC 80 to package 75. Hereinafter, connecting wirings 74a to 74f will be collectively referred to as connecting wirings 74, as appropriate.

[0063] In this manner, after bump components 73 and connecting wiring 74 of IC placement surface 71 temporarily contact each other at pads 81e and 81f, IC 80 is pushed into IC placement surface 71 before bump components 73 and connecting wiring 74 of IC placement surface 71 contact each other at pads 81a to 81d. Consequently, greater pressure is applied to pads 81e to 81f than to pads 81a to 81d, creating an imbalance in the pressure applied during flip-chip bonding between IC 80 and package 75. As a result, excessive force is applied around pads 81e to 81f, potentially degrading the performance of IC 80.

[0064] In the oscillator 1 of this embodiment, the pads 51a-51f do not overlap with any of the external terminals 44 in plan view, and the bump components 46a-46f also do not overlap with any of the external terminals 44 in plan view. Specifically, the pads 51a-51f of the connection wiring 42 on the IC placement surface 11c of the package 15 are positioned at the bottom portion where the external terminals 44 are located. Therefore, compared to a situation where some of the pads 51a-51f overlap with the external terminals 44 in plan view, the height unevenness of the pads 51a-51f on the IC placement surface 11c is reduced. Consequently, during flip-chip bonding between the IC 50 and the package 15, the pressure applied around each of the pads 51a-51f is more uniform and consistent. As a result, the possibility of excessive pressure being applied around some of the pads 51a-51f, which could degrade the performance of the IC 50, is reduced.

[0065] Furthermore, in this embodiment, the connection wiring 42a includes a second portion 422a extending between the pad 51b and the pad 51e when viewed from above. The connection wiring 42a is connected to the power supply pad, i.e., the pad 51a, and is supplied with a DC potential. AC signals flow through the connection wiring 42e connected to the output pad, i.e., the pad 51e, and the connection wiring 42b connected to the first oscillator pad, i.e., the pad 51b. Therefore, these AC signals may interfere with each other, deteriorating noise performance. In this embodiment, the second portion 422a of the connection wiring 42a, which is supplied with a DC potential and exists between the connection wiring 42b and the connection wiring 42e, acts as a shield, thereby reducing interference between these AC signals and reducing deterioration in noise performance.

[0066] Furthermore, in this embodiment, connecting wiring 42d includes a fourth portion 422d extending between pad 51c and pad 51f when viewed from above. Connecting wiring 42d is connected to pad 51d, which is a control pad, and is supplied with a DC potential, which is an output control signal for the clock signal. Thus, fourth portion 422d of connecting wiring 42d, like second portion 422a of connecting wiring 42a, acts as a shield between connecting wiring 42c and connecting wiring 42f. This reduces interference between signals flowing through connecting wiring 42c and connecting wiring 42f, thereby minimizing degradation of noise performance.

[0067] (1-2) Oscillator manufacturing method:

[0068] An example of a method of manufacturing the oscillator 1 will be described.

[0069] First, Au bonding fine wires are used to form bump members 46 on the pads 51 of the IC 50 by ultrasonic bump bonding.

[0070] Next, the bonding process of bonding IC50 to the IC configuration surface 11c of the package 15 is described. The IC50 is turned over and handed over to the end nozzle of the ultrasonic horn of the flip-chip bonding device. Then, the flip-chip bonding device is used to make the surface of the IC50 provided with the solder pad 51 parallel to the IC configuration surface 11c of the package 15 which is in a horizontal position with the mounting surface as the bottom. At this time, the solder pad 51 does not overlap with any of the external terminals 44 when viewed from above. As a result, in the oscillator 1, the bump components 46 are in a position that does not overlap with any of the external terminals 44 when viewed from above.

[0071] Then, the IC50 is moved downwardly by the flip-chip bonding device, approaching the IC configuration surface 11c. The bump component 46 provided on the pad 51 of the IC50 contacts the connection wiring 42 of the IC configuration surface 11c. When the flip-chip bonding device detects its load, a predetermined load is applied to each bump component, and ultrasonic waves are applied to bond the bump component 46 and the connection wiring 42. The ultrasonic conditions are set by the power of the ultrasonic wave and the time for applying the ultrasonic wave. In addition, moderate heat is also required for this bonding. For example, a predetermined heat (for example, 150°C to 200°C) is applied to the package 15 in advance. In addition, the same heat is applied to the package 15 during ultrasonic processing.

[0072] Next, the vibrator 20 is connected and fixed to the connection wiring 41 on the vibrator support surface of the package 15 using a conductive adhesive. The entire package 15, including the IC 50 and vibrator 20, is then annealed at high temperature, including curing of the conductive adhesive. This also removes outgassing from the conductive adhesive and the package 15. The metal cover 16 is then aligned and fixed to the seam ring 14 of the package 15, and then hermetically sealed by seam welding.

[0073] In this way, the oscillator 1 is manufactured.

[0074] (2) Second embodiment:

[0075] (2-1) Oscillator structure:

[0076] Oscillator 1a of this embodiment will be described. Oscillator 1a of this embodiment is identical to oscillator 1 of the first embodiment, except for the position of the second pad group (pads 51e and 51f) in IC 50 and the shape of connection wiring 42 on IC placement surface 11c. Oscillator 1a will be described in terms of its differences from oscillator 1.

[0077] Figure 6 It is a plan view showing the cover 16 and the vibrator 20 of the oscillator 1 a through the transparent surface.

[0078] The connection wiring 42a of this embodiment has a first portion 421a extending further to the right than the connection wiring 42a of the first embodiment. Furthermore, the connection wirings 42b and 42c of this embodiment are identical to the connection wirings 42b and 42c of the first embodiment. Furthermore, the connection wiring 42d of this embodiment has a third portion 421d extending further to the right than the connection wiring 42d of the first embodiment.

[0079] Furthermore, the fifth portion 421e of the connection wiring 42e of this embodiment extends further to the left than the connection wiring 42e of the first embodiment. Furthermore, when viewed from above, the sixth portion 422e does not overlap with the external terminal 44c on the left side, but overlaps with the external terminal 44c on the right side, and its end in the near-front direction is closer to the front side than the end in the near-front direction of the external terminal 44c.

[0080] Furthermore, the seventh portion 421f of the connection wiring 42f of this embodiment extends further to the left than the connection wiring 42f of the first embodiment. Furthermore, in a plan view, the eighth portion 422f does not overlap with the external terminal 44d on the left side, but overlaps with the external terminal 44d on the right side, and its inward end is further inward than the inward end of the external terminal 44d.

[0081] The arrangement position of the first pad group (pads 51a to 51d) of this embodiment is the same as that of the pads 51a to 51d of the first embodiment. The pad 51e of this embodiment is arranged on the connection wiring 42e and is arranged near the end of the sixth portion 422e of the connection wiring 42e in the front direction when viewed from above. Figure 6 As shown in FIG. 4 , a portion of the pad 51 e does not overlap with the external terminal 44 c. Therefore, the bump member 46 e is arranged at a position where a portion of the pad 51 e does not overlap with the external terminal 44 c.

[0082] Furthermore, the pad 51f of this embodiment is arranged on the connection wiring 42f and is arranged near the end portion in the inner direction of the eighth portion 422f of the connection wiring 42f in a plan view. Figure 6 As shown in FIG. 4 , a portion of the pad 51f does not overlap with the external terminal 44d. Therefore, the bump member 46f is arranged at a position where a portion of the pad 51f does not overlap with the external terminal 44d.

[0083] As described above, according to the structure of this embodiment, in oscillator 1a, pads 51a-51d do not overlap with any of external terminals 44 in a plan view, and portions of pads 51a-51d do not overlap with external terminals 44 in a plan view. Therefore, compared to a situation such as oscillator 2, where some of the IC's multiple pads overlap with external terminals 44 and others do not overlap at all, the height disparity of pads 51a-51f on IC placement surface 11c is reduced. Consequently, during flip-chip bonding between IC 50 and package 15, the pressure applied around each of pads 51a-51f is more uniform and consistent. As a result, the possibility of excessive pressure being applied around portions of pads 51a-51f, which could degrade the performance of IC 50, is reduced.

[0084] (2-2) Oscillator manufacturing method:

[0085] A method for manufacturing the oscillator 1 a will be described.

[0086] First, the bump members 46 are formed on the pads 51 of the IC 50 using the same method as the method for manufacturing the oscillator 1 according to the first embodiment.

[0087] Next, IC50 is flipped over and handed over to the end nozzle of the ultrasonic horn of the flip-chip bonding device. Then, the flip-chip bonding device is used to make the surface of IC50 provided with the solder pads 51 parallel to the IC configuration surface 11c of the package 15 which is located in a horizontal position with the mounting surface as the bottom. At this time, the solder pads 51a to 51d do not overlap with any of the external terminals 44 when viewed from above. In addition, a portion of the solder pad 51e does not overlap with the external terminal 44c when viewed from above. In addition, a portion of the solder pad 51f does not overlap with the external terminal 44d when viewed from above. As a result, in the oscillator 1, the bump components 46 are each positioned so that at least a portion does not overlap with any of the external terminals 44 when viewed from above.

[0088] Then, the IC 50 is moved downward by the flip-chip bonding apparatus, approaching the IC placement surface 11c. The bump components 46 provided on the pads 51 of the IC 50 come into contact with the connection wiring 42 on the IC placement surface 11c. When the flip-chip bonding apparatus detects the load, a predetermined load and ultrasonic waves are applied to bond the bump components 46 and the connection wiring 42.

[0089] Next, the vibrator 20 is connected and fixed to the connection wiring 41 by the same method as the method for manufacturing the oscillator 1 of the first embodiment, the lid 16 and the seam ring 14 of the package 15 are aligned and fixed, and then hermetically sealed by seam welding.

[0090] In this way, the oscillator 1a is manufactured.

[0091] (3) The third embodiment:

[0092] The oscillator 1b of this embodiment is described. The oscillator 1b of this embodiment is the same as the oscillator 1a of the second embodiment except that the shape of the external terminal 44 is different in plan view. The oscillator 1b will be described with respect to the differences from the oscillator 1a.

[0093] Figure 7 It is a plan view showing the cover 16 and the vibrator 20 of the oscillator 1 b through a transparent perspective.

[0094] The external terminals 44a, 44c, and 44d of this embodiment have a shape obtained by cutting out a rectangular region from the external terminals 44a, 44c, and 44d of the first embodiment. More specifically, compared to the external terminals 44a, 44c, and 44d of the first embodiment, the external terminals 44a, 44c, and 44d of this embodiment have a shape obtained by cutting out a predetermined rectangular region from the corner of the rectangular region near the center of the second surface 11b when viewed from above. This allows the pads 51e and 51f to completely avoid overlapping with the external terminals 44c and 44d, as compared to the oscillator 1a of the second embodiment.

[0095] External terminal 44b has the same shape as external terminals 44a, 44c, and 44d in the first embodiment. By making external terminal 44b have a different shape from external terminals 44a, 44c, and 44d, the user can understand what each external terminal 44 is. Specifically, in this embodiment, external terminals 44a, 44c, and 44d have a shape that is partially cut away from the shape of external terminal 44b, one of the external terminals 44 that is closer to the first pad group than the second pad group.

[0096] As described above, according to the structure of this embodiment, in oscillator 1b, pads 51a-51f do not overlap at all with any of external terminals 44 when viewed from above. Consequently, the height unevenness of pads 51a-51f on IC placement surface 11c is reduced. Consequently, during flip-chip bonding between IC 50 and package 15, the pressure applied around each of pads 51a-51f is more uniform and consistent. As a result, the possibility of excessive pressure being applied around a portion of pads 51a-51f, which could degrade the performance of IC 50, is reduced.

[0097] In addition, the shapes of the external terminals 44a, 44c, and 44d of this embodiment are not limited to Figure 7 The shape shown in FIG. 1 may be a shape obtained by cutting out a portion of the shape of the external terminals 44a, 44c, and 44d of the first embodiment so as not to overlap with the pad 51. For example, the shape of the external terminals 44a, 44c, and 44d of the present embodiment may be Figure 8 Compared to the external terminals 44 a , 44 c , and 44 d of the first embodiment, the illustrated external terminals have a shape obtained by cutting off corners of a rectangular region near the center of the second surface 11 b in a plan view.

[0098] Furthermore, the external terminals 44a, 44c, and 44d of this embodiment are all shaped by partially cutting away from the external terminals 44a, 44c, and 44d of the first embodiment. However, since the second pad group is more likely to overlap with the external terminals 44 than the first pad group, at least the external terminals 44 (44c, 44d) that are closer to the second pad group than to the first pad group may be shaped by partially cutting away from the external terminals 44c and 44d of the first embodiment, so that the external terminals 44 that are closer to the first pad group than the second pad group remain the same as in the first embodiment.

[0099] Note that, except for the use of the external terminal 44 of this embodiment, the manufacturing method of the oscillator 1 b is the same as the manufacturing method of the oscillator 1 of the first embodiment.

[0100] (4) Other implementation methods:

[0101] The above embodiment is an example of implementing the present invention. In addition, various embodiments can be adopted in which at least one of the position of each pad 51 in IC 50 and the position or shape of external terminal 44 is adjusted so that at least a portion of each pad 51 does not overlap with external terminal 44.

[0102] In the above embodiments, pads 51a to 51f serve as a power pad, a first oscillator pad, a second oscillator pad, a control pad, a ground pad, and an output pad, respectively. However, pads 51a to 51f may serve different functions. For example, pad 51a may serve as a control pad, and pad 51d may serve as a power pad. Furthermore, the functions of connecting wirings 42a to 42f and external terminals 44a to 44f may differ from those in the above embodiments, depending on the function of pads 51a to 51f.

[0103] In each of the above embodiments, a quartz crystal resonator is used as the resonator 20. However, other types of resonators such as a ceramic resonator may be used as the resonator 20.

[0104] Furthermore, in each of the above embodiments, at least a portion of each pad 51 does not overlap with external terminal 44. The portion of IC placement surface 11c that overlaps external terminal 44 when viewed from above is higher than the surrounding portion. Furthermore, due to the influence of external terminal 44, the portion of IC placement surface 11c that does not overlap with external terminal 44 when viewed from above becomes higher the closer it is to external terminal 44 and lower the farther it is from external terminal 44. Therefore, by setting the placement position of each pad 51 within a predetermined distance from external terminal 44 when viewed from above, it is possible to further reduce the unevenness in the placement heights of pads 51a to 51f on IC placement surface 11c. This distance is the shortest distance between the outer edge of external terminal 44 and the outer edge of pad 51. Therefore, when a portion of pad 51 overlaps external terminal 44, the distance between pad 51 and external terminal 44 is zero. Examples of this predetermined distance include twice or three times the width of pad 51.

[0105] Furthermore, in each of the above embodiments, the first pad group includes four pads 51 (51a-51d), and the second pad group includes two pads 51 (51e-51f). However, the number of pads 51 included in the first and second pad groups is not limited to this. For example, the first and second pad groups may each include three pads 51.

[0106] Furthermore, in each of the above-described embodiments, the pads 51 included in the second pad group are closer to the external terminals 44 in a plan view than the pads 51 included in the first pad group. Therefore, they are more likely to overlap with the external terminals 44 in a plan view, and a height change due to the external terminals 44 is more likely to occur. Therefore, by making the number of pads 51 included in the first pad group greater than the number of pads 51 included in the second pad group, the number of pads 51 whose arrangement position is elevated due to the influence of the external terminals 44 can be reduced.

[0107] Furthermore, in each of the above-described embodiments, more than half of the plurality of pads 51 do not overlap at all with the external terminals 44 when viewed from above. Thus, by having more than half of the plurality of pads 51 do not overlap at all with the external terminals 44 when viewed from above, the number of pads 51 whose arrangement position is elevated due to the influence of the external terminals 44 can be reduced.

[0108] Regarding the external terminals and the package, it is sufficient that a portion of the surface of the package where the circuit elements are arranged overlaps with the external terminals when viewed from above.

[0109] The circuit element may be configured so as to be arranged so that each pad does not overlap with the external terminal at all in a plan view.

[0110] On the surface of the package where the circuit elements are arranged, the correspondence between the distance from the outer edge of the external terminal and the change in height when viewed from above may be measured, and the predetermined distance may be determined based on the measurement results.

[0111] The predetermined shape may be the shape of a component used as an external terminal in a plan view. For example, it may be the shape of an existing component used as an external terminal in a plan view.

Claims

1. An oscillator comprising: A package having a plurality of external terminals on a mounting surface, wherein the package is rectangular in a plan view and has a first side, a second side opposite to the first side, a third side, and a fourth side opposite to the third side; a circuit element housed in the package, the circuit element being rectangular in plan view and having a fifth side aligned with the first side, a sixth side opposite the fifth side and further from the first side than the fifth side, a seventh side, and an eighth side opposite the seventh side; and a vibrator housed in the package and electrically connected to the circuit element; The circuit element is electrically connected to the package via a plurality of pads, and the plurality of pads are bonded to the package via a plurality of bump components. The circuit element overlaps with at least one of the plurality of external terminals in a plan view. The plurality of bump members are each bonded to the package at a position where at least a portion thereof does not overlap with the plurality of external terminals in a plan view. The plurality of pads include a first pad group disposed along the fifth side closer to the fifth side than to the sixth side, and a second pad group disposed along the sixth side closer to the sixth side than to the fifth side. The distance between the first side and the fifth side is greater than the distance between the second side and the sixth side. The distance between the sixth side and the second pad group is greater than the distance between the fifth side and the first pad group.

2. The oscillator according to claim 1, wherein The number of pads included in the first pad group is greater than the number of pads included in the second pad group.

3. The oscillator according to claim 1 or 2, wherein: The external terminals, among the plurality of external terminals, which are closer to the second pad group than the first pad group, have a shape that is partially cut out from a predetermined shape so as not to overlap with at least a portion of the plurality of bump members in a plan view.

4. The oscillator according to claim 3, wherein The predetermined shape is a shape that is closer to one of the plurality of external terminals of the first pad group than to the second pad group.

5. The oscillator according to claim 1 or 2, wherein: When viewed from above, more than half of the plurality of pads do not overlap with the plurality of external terminals at all.

6. The oscillator according to claim 1 or 2, wherein: The plurality of pads include a power supply pad to which a power supply voltage is applied, a ground pad to which a ground potential is supplied, a first vibrator pad electrically connected to the vibrator, a second vibrator pad electrically connected to the vibrator, an output pad to which a clock signal is output, and a control pad to which an output control signal of the clock signal is input.

7. The oscillator according to claim 1 or 2, wherein: The first pad group includes a power pad to which a power supply voltage is applied, a first vibrator pad electrically connected to the vibrator, a second vibrator pad electrically connected to the vibrator, and a control pad to which an output control signal of a clock signal is input. The second pad group includes a ground pad to which a ground potential is supplied and an output pad to which a clock signal is output. The plurality of external terminals include a power supply terminal and a control terminal provided closer to the first side than to the second side, and a ground terminal and an output terminal provided closer to the second side than to the first side.

8. The oscillator according to claim 7, wherein The package includes a power supply wiring electrically connected to the power supply pad, The power supply wiring includes a first portion connecting the power supply pad and the power supply terminal, and a second portion extending between the output pad and the first vibrator pad in a plan view.

9. The oscillator according to claim 7, wherein The package has a control wiring electrically connected to the control pad, The control wiring includes a third portion connecting the control pad and the control terminal, and a fourth portion extending between the ground pad and the second vibrator pad in a plan view.

10. A method for manufacturing an oscillator, the oscillator comprising: a package having a plurality of external terminals on a mounting surface, the package being rectangular in plan view and having a first side, a second side opposite to the first side, a third side, and a fourth side opposite to the third side; a circuit element housed in the package, the circuit element being rectangular in plan view and having a fifth side aligned with the first side, a sixth side opposite to the fifth side and further away from the first side than the fifth side, a seventh side, and an eighth side opposite to the seventh side, the circuit element overlapping at least one of the plurality of external terminals in plan view; and an oscillator housed in the package and electrically connected to the circuit element, wherein: The manufacturing method includes the following bonding step: bonding a plurality of pads of the circuit element to the package via a plurality of bump members, thereby electrically connecting the circuit element and the package; In the bonding step, each of the plurality of bump members is positioned so that at least a portion thereof does not overlap with the plurality of external terminals in a plan view. The plurality of pads include a first pad group disposed along the fifth side closer to the fifth side than to the sixth side, and a second pad group disposed along the sixth side closer to the sixth side than to the fifth side. The distance between the first side and the fifth side is greater than the distance between the second side and the sixth side. The distance between the sixth side and the second pad group is greater than the distance between the fifth side and the first pad group.

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