JP2013145964A - Piezoelectric device and manufacturing method of piezoelectric device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a piezoelectric device in which a metal cover body can be prevented from being displaced, and a manufacturing method of the piezoelectric device.SOLUTION: A piezoelectric device (200) comprises a ceramic base plate (220) including a first face and a second face at an opposite side, a piezoelectric oscillation piece (130) mounted on the first face, and a metal cover body (110) which is metallic, having a wall surface (112) extending from a ceiling face (113) so as to cover the piezoelectric oscillation piece. In the piezoelectric device, the ceramic base plate includes a protruding part (225) formed around the first face and protruding from the first face, a connecting electrode (121) formed inside of the protruding part and electrically connected to the piezoelectric oscillation piece, an external electrode (224) formed on the second face, and a wiring electrode (222) extending from the connecting electrode to an external electrode. The metal cover body is disposed so as to bring a terminal portion of its wall surface into contact with the protruding part, and the terminal portion of the wall surface and the protruding part are sealed by a sealing material.

Description

  The present invention relates to a piezoelectric device using a ceramic mother substrate and a method for manufacturing the piezoelectric device. More specifically, a plurality of piezoelectric vibrating pieces are placed on a ceramic mother substrate, and a plurality of metal cover bodies covering the piezoelectric vibrating pieces are further provided. The present invention relates to a piezoelectric device manufactured by mounting and a method for manufacturing the piezoelectric device.

  In order to increase mass productivity, a piezoelectric device manufactured using a ceramic mother substrate has been proposed. For example, the manufacturing method of Patent Document 1 forms a connection electrode by printing and baking a metal paste on a ceramic mother substrate. In this manufacturing method, the piezoelectric vibrating piece is mounted on the connection electrode, the piezoelectric vibrating piece is covered with the metal cover body, and the metal cover body and the ceramic mother substrate are joined with a non-conductive sealing material. Thereafter, by cutting from the ceramic mother substrate at a break line formed on the ceramic mother substrate, hundreds to thousands of piezoelectric devices are completed.

JP 2011-211681 A

  However, warpage of the ceramic mother substrate alone, distortion of break lines that specify individual regions in the ceramic mother substrate, variation in accuracy of the metal cover body, or excessive application amount of the sealing material may occur. Due to these factors, misalignment of the metal cover body in the individual piece region, flow of the sealing material into the break line, and the like may occur, and a defective product may be manufactured. Furthermore, when considering miniaturization of the piezoelectric device, the clearance between adjacent metal cover bodies becomes narrower, and the mounting accuracy of the metal cover mounting device or the technology for controlling the coating amount of the sealing material is limited. ing.

  An object of this invention is to provide the manufacturing method of a piezoelectric device and a piezoelectric device which can prevent the shift | offset | difference of a metal cover body.

  A piezoelectric device according to a first aspect extends from a ceiling surface so as to cover a ceramic base plate including a first surface and a second surface opposite to the first surface, a piezoelectric vibrating piece placed on the first surface, and the piezoelectric vibrating piece. A surface-mount type piezoelectric device having a metallic metal cover body having a curved wall surface. In this piezoelectric device, the ceramic base plate is formed around the first surface and protrudes from the first surface, the connection electrode formed inside the protrusion and electrically connected to the piezoelectric vibrating piece, the second An external electrode formed on the surface and a wiring electrode extending from the connection electrode to the external electrode, the end of the wall surface of the metal cover body is disposed so as to contact the protrusion, and the end of the wall and the protrusion are It is sealed with a sealing material.

  In the piezoelectric device according to the second aspect, the end portion of the metal cover body has a flange bent outward from the wall surface, and the flange is disposed inside the protrusion.

  In the piezoelectric device according to the third aspect, the end of the metal cover body has a flange bent outward from the wall surface, and the flange is disposed outside the protrusion.

  The piezoelectric device according to the fourth aspect, the protrusion is formed at a position avoiding the wiring electrode, and the insulating layer is formed on the wiring electrode positioned at the end of the metal cover body.

  A piezoelectric device of a fifth aspect extends from a ceiling surface so as to cover a ceramic base plate including a first surface and a second surface opposite to the first surface, a piezoelectric vibrating piece placed on the first surface, and the piezoelectric vibrating piece. A surface-mount type piezoelectric device having a metallic metal cover body having a curved wall surface. In this piezoelectric device, the ceramic base plate has an annular groove having a predetermined width formed so as to be recessed from the first surface around the first surface, and is electrically connected to the piezoelectric vibrating piece formed in the annular groove. It has a connection electrode, an external electrode formed on the second surface, and a wiring electrode extending from the connection electrode to the external electrode. Moreover, the edge part of the wall surface of a metal cover body is arrange | positioned at the annular groove, and the edge part and annular groove of the wall surface are sealed with the sealing material.

  In the piezoelectric device according to the sixth aspect, the end portion of the metal cover body has a flange bent outward from the wall surface, and the width of the flange is shorter than the predetermined width of the annular groove.

  A method for manufacturing a piezoelectric device according to a seventh aspect is a method for manufacturing a surface-mount type piezoelectric device having a metallic metal cover body having a wall surface extending from a ceiling surface, and includes a first surface and a second surface on the opposite side. A sheet-like ceramic fabric including a surface, a break line for specifying an area of each ceramic base plate, a through-hole penetrating from the first surface to the second surface at a corner of the region, and a first inside the break line. A step of forming a protrusion protruding from the first surface on one side and then firing to form a sheet-like ceramic mother substrate, and applying and firing a metal paste, a piezoelectric vibrating piece inside the protrusion A connection electrode electrically connected to the substrate, an external electrode on the second surface, a wiring electrode extending from the connection electrode to the external electrode, a step of placing the piezoelectric vibrating reed on the connection electrode, and a ceramic mother substrate Apply a stop material Comprising a degree, a metal cover arranged along the protruding portion, and the step of sealing the the protrusion metal cover plate with a sealing material, a.

  In the method of manufacturing the piezoelectric device according to the eighth aspect, in the step of forming the ceramic mother substrate according to the seventh aspect, the break line, the through hole, and the protrusion are formed by pushing the mold against the ceramic cloth.

  A method for manufacturing a piezoelectric device according to a ninth aspect is a method for manufacturing a surface-mount type piezoelectric device having a metallic metal cover body having a wall surface extending from a ceiling surface, and includes a first surface and a second surface on the opposite side. A sheet-like ceramic fabric including a surface, a break line for specifying an area of each ceramic base plate, a through-hole penetrating from the first surface to the second surface at a corner of the region, and a first inside the break line. Forming an annular groove having a predetermined width formed on one surface so as to be recessed from the first surface, followed by firing to form a sheet-like ceramic mother substrate; applying and firing a metal paste; Forming a connection electrode electrically connected to the piezoelectric vibrating piece inside, an external electrode on the second surface, and a wiring electrode extending from the connection electrode to the external electrode; and a step of placing the piezoelectric vibrating piece on the connection electrode; Ceramic mother board And a step of applying a sealant, a step of end of the metal cover body is arranged to enter the annular groove, for sealing the end portion and the annular groove and the sealing material of the metal cover body.

  In the method for manufacturing a piezoelectric device according to the tenth aspect, in the step of forming the ceramic mother substrate according to the ninth aspect, the break line, the through hole, and the annular groove are formed by pushing the mold against the ceramic cloth.

  According to the piezoelectric device and the manufacturing method of the piezoelectric device of the present invention, it is possible to prevent the metal cover body of the piezoelectric device from shifting.

1 is an exploded perspective view of a piezoelectric device 100. FIG. It is AA sectional drawing of FIG. 3 is a flowchart illustrating a method for manufacturing the piezoelectric device 100. 5 is a flowchart illustrating a process of forming a ceramic mother substrate W120. (A) is a partial top view of the ceramic fabric | dye in which the break line 171, the through-hole 123, and the annular groove | channel 125 were formed. (B) is BB sectional drawing of Fig.5 (a). (A) is a fragmentary sectional view of ceramic mother board W120 in which an electrode was formed. FIG. 5B is a partial cross-sectional view of the ceramic mother substrate W120 on which the piezoelectric vibrating piece 130 is placed. (C) is a partial cross-sectional view of the ceramic mother substrate W120 to which the sealing material 142 is applied. FIG. 4D is a partial cross-sectional view of the ceramic mother substrate W120 on which the metal cover body 110 is placed. 2 is an exploded perspective view of a piezoelectric device 200. FIG. It is CC sectional drawing of FIG. (A) is a partial top view of the ceramic fabric | dye in which the break line 171, the through-hole 229, and the projection part 225 were formed. (B) is DD sectional drawing of Fig.9 (a). (A) is an enlarged plan view of the ceramic mother substrate W220 on which electrodes are formed. (B) is an enlarged plan view of a ceramic mother substrate W220 on which an insulating layer 228 is formed. (C) is a partial cross-sectional view of the ceramic mother board W220 on which the metal cover body 110 is placed. 3 is an exploded perspective view of a piezoelectric device 300. FIG. It is EE sectional drawing of FIG.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the drawings. In the following description, the present invention is not limited to these embodiments unless otherwise specified to limit the present invention.

(First embodiment)
<Configuration of Piezoelectric Device 100>
FIG. 1 is an exploded perspective view of the piezoelectric device 100. The piezoelectric device 100 includes a metal cover body 110, a ceramic base plate 120, and a piezoelectric vibrating piece 130. As the piezoelectric vibrating piece 130, for example, an AT-cut crystal vibrating piece is used. The AT-cut quartz crystal resonator element has a principal surface (YZ plane) inclined with respect to the Y axis of the crystal axis (XYZ) by 35 degrees 15 minutes from the Z axis in the Y axis direction around the X axis. In the following description, the new axes tilted with respect to the axial direction of the AT-cut quartz crystal vibrating piece are used as the Y ′ axis and the Z ′ axis. That is, in the piezoelectric device 100, the long side direction of the piezoelectric device 100 is described as the X-axis direction, the height direction of the piezoelectric device 100 is defined as the Y′-axis direction, and the direction perpendicular to the X and Y′-axis directions is described as the Z′-axis direction. .

  In the piezoelectric device 100, the piezoelectric vibrating piece 130 is placed on the surface on the + Y′-axis side of the ceramic base plate 120. Furthermore, the piezoelectric device 100 is formed by bonding the metal cover body 110 to the surface on the + Y′-axis side of the ceramic base plate 120 via the sealing material 142 (see FIG. 2) so as to seal the piezoelectric vibrating piece 130. The The piezoelectric device 100 is a surface-mount type piezoelectric device mounted on a printed circuit board or the like.

  The metal cover body 110 is formed in a box shape having a recess 111 that is recessed in the + Y′-axis direction on the surface at the −Y′-axis side. Further, the metal cover body 110 includes four wall surfaces 112 surrounding the recess 111, a ceiling surface 113 joined to the + Y′-axis side of each wall surface 112, and a −Y′-axis side of each wall surface 112. The flange 114 is formed in a bowl shape so as to be bent outward from the wall surface 112.

  In the piezoelectric vibrating piece 130, excitation electrodes 131 are formed on surfaces on the + Y′-axis side and the −Y′-axis side, and extraction electrodes 132 are extracted from the excitation electrodes 131, respectively. From the excitation electrode 131 formed on the surface at the + Y′-axis side of the piezoelectric vibrating piece 130, the extraction electrode 132 is drawn out to the X-axis side, and the extraction electrode 132 further extends to the −Z′-axis side surface of the piezoelectric vibrating piece 130. Through the surface on the −Y′-axis side. The extraction electrode 132 drawn from the excitation electrode 131 formed on the surface of the piezoelectric vibrating piece 130 on the −Y ′ axis side extends from the excitation electrode 131 to the −X axis side, and further, the + Z ′ axis of the piezoelectric vibrating piece 130. It is pulled out to the surface on the + Y′-axis side through the side surface on the side.

  A pair of connection electrodes 121 is formed on the ceramic base plate 120 on the surface at the + Y′-axis side. Each connection electrode 121 is electrically connected to each extraction electrode 132 of the piezoelectric vibrating piece 130 via a conductive adhesive 141 (see FIG. 2). A pair of external electrodes 124 is formed on the surface at the −Y′-axis side of the ceramic base plate 120. A pair of through holes 123 penetrating the ceramic base plate 120 in the Y′-axis direction are formed in the ceramic base plate 120, and the pair of connection electrodes 121 and the pair of external electrodes 124 are formed through the respective through holes 123. The pair of wiring electrodes 122 are electrically connected. In addition, an annular groove 125 recessed to the −Y′-axis side so as to surround the entire electrode formed on the + Y′-axis side surface of the ceramic base plate 120 is formed on the + Y′-axis side surface of the ceramic base plate 120. Is formed. The annular groove 125 is formed in such a size that the side of the wall surface 112 of the metal cover body 110 on the −Y′-axis side and the flange 114 can be accommodated. That is, the width of the flange 114 is shorter than the width of the groove of the annular groove 125.

  FIG. 2 is a cross-sectional view taken along the line AA of FIG. The piezoelectric vibrating piece 130 is placed on the surface on the + Y′-axis side of the ceramic base plate 120. The extraction electrode 132 of the piezoelectric vibrating piece 130 and the connection electrode 121 of the ceramic base plate 120 are electrically connected via a conductive adhesive 141. Thereby, the excitation electrode 131 of the piezoelectric vibrating piece 130 is electrically connected to the external electrode 124. Further, the metal cover body 110 is placed in the annular groove 125 of the ceramic base plate 120 via the sealing material 142. As a result, the metal cover body 110 and the annular groove 125 are sealed, and the piezoelectric vibrating piece 130 is sealed in the recess 111. The piezoelectric device 100 is mounted on a printed circuit board or the like by soldering the external electrode 124.

<Method for Manufacturing Piezoelectric Device 100>
FIG. 3 is a flowchart showing a method for manufacturing the piezoelectric device 100. Below, the manufacturing method of the piezoelectric device 100 is demonstrated with reference to the flowchart of FIG.

  In step S101, the piezoelectric vibrating piece 130 is prepared. The piezoelectric vibrating piece 130 is prepared by forming a plurality of piezoelectric vibrating pieces 130 on a piezoelectric wafer (not shown) formed of a piezoelectric material and separating each piezoelectric vibrating piece 130 from the piezoelectric wafer.

  In step S201, a ceramic mother substrate W120 is prepared. The ceramic mother substrate W120 is a substrate on which a plurality of ceramic base plates 120 are formed. With reference to FIG. 4, step S201 will be described in more detail.

  FIG. 4 is a flowchart illustrating a process of forming the ceramic mother substrate W120. That is, in step S201, the ceramic mother substrate W120 is prepared through the flowchart shown in FIG.

  In step S501 of FIG. 4, a sheet-shaped ceramic fabric C120 is prepared.

  In step S502, it is determined whether or not the annular groove 125 is formed in the ceramic base plate. When the annular groove 125 is formed, the process proceeds to step S503, and when the annular groove 125 is not formed, the process proceeds to step S504. In the first embodiment, step S503 in which the annular groove 125 is formed is described, and step S504 in which the annular groove 125 is not formed is described in the second embodiment.

  In step S503, the break line 171, the through hole 123, and the annular groove 125 are formed in the ceramic fabric C120. The break line 171 (see FIG. 5A) is a line for dividing the ceramic mother substrate W120 in step S404 described later.

  FIG. 5A is a partial plan view of the ceramic fabric C120 in which the break line 171, the through hole 123, and the annular groove 125 are formed. A break line 171, a through-hole 123, and an annular groove 125 formed in step S <b> 503 are shown in the ceramic fabric C <b> 120 in FIG. The break line 171 is, for example, a line formed by cutting a surface of the ceramic fabric on the + Y′-axis side and extending in the X-axis direction and the Z′-axis direction. In the break line 171, the ceramic mother substrate W120 is easily divided. One ceramic base plate 120 is formed in a region surrounded by the break line 171, that is, the break line 171 is formed at the boundary between adjacent ceramic base plates 120.

  FIG.5 (b) is BB sectional drawing of Fig.5 (a). In FIG. 5B, one ceramic base plate 120 is formed in a region sandwiched by the break lines 171. The break line 171, the through hole 123, and the annular groove 125 formed in the ceramic fabric C120 are formed by pressing the ceramic fabric C120 with a mold.

  In step S505, the ceramic fabric C120 is fired. The ceramic dough C120 is hardened by firing and becomes a ceramic mother substrate W120. The firing of the ceramic in step S505 is performed at a temperature of 1500 to 1600 ° C., for example. Steps S503 to S505 are processes for forming a sheet-shaped ceramic mother substrate.

  Returning to FIG. 3, in step S202, electrodes are formed on the ceramic mother substrate W120. The electrodes formed in step S202 are the connection electrode 121, the external electrode 124, and the wiring electrode 122. Step S202 is a process of forming a wiring electrode.

  FIG. 6A is a partial cross-sectional view of the ceramic mother substrate W120 on which electrodes are formed. External electrodes 124, wiring electrodes 122, and connection electrodes 121 are formed on the ceramic mother substrate W120. These electrodes can be formed, for example, by applying or printing a metal paste of AgPd alloy on the ceramic mother substrate W120 and firing at about 850 ° C. The through hole 123 is sealed with the wiring electrode 122 in step S202.

  In step S301, the metal cover body 110 is prepared. In step S301, the metal cover bodies 110 made of metal for the number of piezoelectric devices 100 to be manufactured are prepared. For the metal cover 110, for example, Kovar, which is an alloy in which nickel and cobalt are mixed with iron, is used.

  In step S401, the piezoelectric vibrating piece 130 is placed on the ceramic mother substrate W120. Step S401 is a process of placing the piezoelectric vibrating piece on the connection electrode.

  FIG. 6B is a partial cross-sectional view of the ceramic mother substrate W120 on which the piezoelectric vibrating piece 130 is placed. The piezoelectric vibrating piece 130 is bonded to the connection electrode 121 formed on the ceramic mother substrate W120 via the conductive adhesive 141. In step S401, the conductive adhesive 141 is applied to the connection electrode 121 formed on the ceramic mother substrate W120, and the lead electrode 132 of the piezoelectric vibrating piece 130 is electrically connected to the connection electrode 121 via the conductive adhesive 141. Thus, the piezoelectric vibrating piece 130 is placed on the ceramic mother substrate W120.

  In step S402, the sealing material 142 is applied to the ceramic mother substrate W120. Step S402 is a process of applying a sealing material to the ceramic mother substrate.

  FIG. 6C is a partial cross-sectional view of the ceramic mother substrate W120 to which the sealing material 142 is applied. The sealing material 142 is applied in the groove of the annular groove 125 of the ceramic mother substrate W120. For the sealing material 142, for example, a resin such as polyimide or low-melting glass can be used. As the low melting point glass, for example, a vanadium glass having a transition point around 295 ° C. and a softening point around 350 ° C. can be used.

  In step S <b> 403, the metal cover body 110 is placed on the ceramic mother substrate W <b> 120, and the end portion on the −Y′-axis side of the metal cover body 110 and the annular groove 125 are sealed with the sealing material 142. Step S403 is a step of arranging the end portion of the metal cover body 110 so as to enter the annular groove 125, and sealing the end portion of the metal cover body 110, the annular groove 125, and the sealing material 142.

  FIG. 6D is a partial cross-sectional view of the ceramic mother substrate W120 on which the metal cover body 110 is placed. In step S403, the metal cover body 110 is placed so that the end portion on the −Y′-axis side of the metal cover body 110 enters the annular groove 110 of the ceramic mother substrate W120. Furthermore, the sealing material 142 is heated and solidified, whereby the metal cover body 110 and the annular groove 125 are sealed, and the recess 111 of the metal cover body 110 is sealed.

  In step S404, the ceramic mother substrate W120 is divided by the break line 171. Thereby, individual piezoelectric devices 100 are formed.

  In the manufacturing method of the piezoelectric device 100 shown above, the annular groove 125 is formed and the metal cover body 110 is put into the annular groove 125, thereby preventing the metal cover body 110 from being displaced during the manufacturing of the piezoelectric device 100. Yes. Further, since the sealing material 142 is applied to the annular groove 125, the sealing material 142 is applied to the break line 171 during the manufacturing of the piezoelectric device 100, and the division of the substrate in step S404 is not hindered.

(Second Embodiment)
The ceramic base plate of the piezoelectric device may be prevented from shifting the metal cover body by forming a protrusion instead of the annular groove. Hereinafter, the piezoelectric device 200 and the piezoelectric device 300 having protrusions formed on the ceramic base plate will be described. Moreover, in the following description, the same code | symbol is attached | subjected about the same part as 1st Embodiment, and the description is abbreviate | omitted.

<Configuration of Piezoelectric Device 200>
FIG. 7 is an exploded perspective view of the piezoelectric device 200. The piezoelectric device 200 includes a metal cover body 110, a piezoelectric vibrating piece 130, and a ceramic base plate 220.

  The ceramic base plate 220 has a pair of connection electrodes 121 formed on the surface at the + Y′-axis side. Each connection electrode 121 is joined to the extraction electrode 132 of the piezoelectric vibrating piece 130 via the conductive adhesive 141 (see FIG. 8). A pair of external electrodes 224 is formed on the surface of the ceramic base plate 220 on the −Y′-axis side. A castellation 223 recessed inward of the ceramic base plate 220 is formed on the side surfaces of the four corners of the ceramic base plate 220, and the pair of connection electrodes 121 and the pair of external electrodes 224 are formed via the castellation 223. They are electrically connected by a pair of wiring electrodes 222. Further, an insulating layer 228 is formed in the area where the end surface of the metal cover body 110 on the −Y′-axis side and the flange 114 are in contact with the ceramic base plate 220 and in the vicinity thereof. Since the insulating layer 228 is formed after the wiring electrode 222 is formed, the insulating layer 228 is formed on the surface of the wiring electrode 222 in a region where the insulating layer 228 and the wiring electrode 222 intersect. Protrusions 225 are formed on the inside of the corner on the −Z′-axis side on the −X-axis side and the inside of the + Z′-axis side on the + X-axis side in the region on the ceramic base plate 220 surrounded by the insulating layer 228. ing.

  8 is a cross-sectional view taken along the line CC of FIG. A piezoelectric vibrating piece 130 is placed on the surface of the ceramic base plate 220 on the + Y′-axis side. The extraction electrode 132 of the piezoelectric vibrating piece 130 and the connection electrode 121 of the ceramic base plate 220 are electrically connected via the conductive adhesive 141, whereby the excitation electrode 131 of the piezoelectric vibrating piece 130 is electrically connected to the external electrode 224. Connected to. Further, the metal cover body 110 and the ceramic base plate 220 are joined via a sealing material 142. The surface on the recess 111 side of the wall surface 112 is disposed so as to be in contact with or close to the protrusion 225 on the surface on the + Y′-axis side of the ceramic base plate 220. Since the position of the metal cover body 110 is fixed by the protrusion 225, the position of the metal cover body 110 does not shift in the X-Z ′ plane. In the piezoelectric device 200, the insulating layer 228 is formed between the wiring electrode 222 and the sealing material 142, thereby ensuring electrical insulation between the metal cover body 110 and the wiring electrode 222.

<Method for Manufacturing Piezoelectric Device 200>
The piezoelectric device 200 is manufactured by the method of the flowchart shown in FIG. Hereinafter, a method for manufacturing the piezoelectric device 200 will be described with reference to FIG.

  In step S101, the piezoelectric vibrating piece 130 is prepared, in step S201, the ceramic mother board W220 is prepared, and in step S301, the metal cover body 110 is prepared. Step S201 will be described with reference to FIG.

  In step S501 of FIG. 4, a sheet-like ceramic fabric C220 is prepared. In step S502, it is determined whether or not an annular groove is formed on the ceramic base plate. Since the annular groove is not formed in the piezoelectric device 200, the process proceeds to step S504. In step S504, a break line 171, a through hole 229, a protrusion 225, and the like are formed on the ceramic fabric C220.

  FIG. 9A is a partial plan view of the ceramic fabric C220 on which the break line 171, the through hole 229, and the protrusion 225 are formed. In step S504, the break line 171, the through-hole 229, and the projection part 225 are formed in the ceramic fabric C220. The through-hole 229 is formed at the corner of the region of the ceramic fabric C220 where each ceramic base plate 220 is formed, that is, at the intersection of the break line 171 extending in the X-axis direction and the break line 171 extending in the Z′-axis direction. . Through hole 229 becomes castellation 223 (see FIG. 7) after ceramic mother substrate W220 is divided by break line 171 in step S404 described later. In FIG. 9A, a region where the opening surface of the recess 111 overlaps the ceramic base plate 220 when the metal cover body 110 is placed on the ceramic base plate 220 is surrounded by a dotted line 174. The protrusions 225 are formed at the corners on the + Z′-axis side on the + X-axis side and the −Z′-axis side on the −X-axis side of the region surrounded by the dotted line 174.

  FIG.9 (b) is DD sectional drawing of Fig.9 (a). The through hole 229 is a hole that penetrates the ceramic fabric C220 in the Y′-axis direction, and the protrusion 225 is a portion that projects in the + Y′-axis direction from the surface on the + Y′-axis side of the ceramic fabric C220. Such through holes 229, protrusions 225, and break lines 171 are formed by pressing the ceramic fabric C220 with a mold.

  In step S505, the ceramic dough C220 is fired to form a sheet-shaped ceramic mother substrate W220. After step S505, electrodes are formed on the ceramic mother substrate W220 in step S202 of FIG. In step S202 in the method for manufacturing the piezoelectric device 200, the insulating layer 228 is formed after the electrodes are formed.

  FIG. 10A is an enlarged plan view of a ceramic mother substrate W220 on which electrodes are formed. FIG. 10A shows a state where an electrode is formed in a region surrounded by a one-dot chain line 172 in FIG. A connection electrode 121 and a wiring electrode 222 are formed on the surface on the + Y′-axis side of the ceramic mother substrate W220. An external electrode 224 (see FIG. 8) is formed on the surface of the ceramic mother substrate W220 on the −Y′-axis side. The wiring electrode 222 is also formed on the inner wall of the through hole 229 and electrically connects the connection electrode 121 and the external electrode 224. Similar to the piezoelectric device 100 shown in the first embodiment, these electrodes are formed by applying or printing a metal paste on the ceramic mother substrate W220 and baking it.

  FIG. 10B is an enlarged plan view of the ceramic mother substrate W220 on which the insulating layer 228 is formed. An insulating layer 228 is formed in and around a region where the metal cover body 110 is bonded to the ceramic mother substrate W220. Although only the sealing material 142 (see FIG. 8) can form electrical insulation between the metal cover body 110 and the wiring electrode 222, the piezoelectric device 200 further includes an insulating layer 228 to form a metal cover. The electrical insulation between the body 110 and the wiring electrode 222 is further ensured.

  Returning to FIG. 3, in step S401, the piezoelectric vibrating piece 130 is placed on the ceramic mother substrate W220. In step S402, the sealing material 142 is applied to the ceramic mother substrate W220. In step S403, the metal cover body is applied to the ceramic mother substrate W220. 110 is placed.

  FIG. 10C is a partial cross-sectional view of the ceramic mother substrate W220 on which the metal cover body 110 is placed. FIG.10 (c) is sectional drawing containing the DD cross section of Fig.9 (a). The sealing material 142 applied to the ceramic mother substrate W <b> 220 in step S <b> 402 is formed on a part of the surface of the insulating layer 228. In step S <b> 403, the metal cover body 110 is placed on the sealing material 142. Therefore, at least the insulating layer 228 and the sealing material 142 are formed between the metal cover body 110 and the wiring electrode 222. Further, since the metal cover body 110 is fixed in the XZ ′ plane by forming the protrusions 225 on the ceramic mother board W220, generation of defective products due to the displacement of the metal cover body 110 is suppressed. Yes.

<Configuration of Piezoelectric Device 300>
By disposing the protrusion 225 in the sealed recess 111, the protrusion 225 prevents the metal cover body 110 from shifting. However, the protrusion may be formed outside the metal cover body 110. Below, the piezoelectric device 300 in which the protrusion part is formed in the outer side of the metal cover body 110 is demonstrated. Moreover, in the following description, the same code | symbol is attached | subjected about the same part as the piezoelectric device 200 and the electric device 300, and the description is abbreviate | omitted.

  FIG. 11 is an exploded perspective view of the piezoelectric device 300. The piezoelectric device 300 includes a metal cover 110, a piezoelectric vibrating piece 130, and a ceramic base plate 320. A protrusion 325 is formed on the ceramic base plate 320. Other configurations are the same as those of the ceramic base plate 220. On the surface at the + Y′-axis side of the ceramic base plate 320 of FIG. 11, a portion where the outer periphery of the flange 114 of the metal cover body 110 overlaps is indicated by a dotted line 173. That is, the metal cover body 110 is placed inside the dotted line 173 of the ceramic base plate 320. The protrusions 325 formed on the ceramic base plate 320 are outside the dotted line 173 on the + X axis side, the −X axis side, the + Z ′ axis side, and the −Z ′ axis side, and are in contact with the dotted line 173 or the dotted line 173. Are formed close to each other.

  12 is a cross-sectional view taken along the line E-E in FIG. 11. In the piezoelectric device 300, the piezoelectric vibrating piece 130 is placed on the connection electrode 121 of the ceramic base plate 320 via the conductive adhesive 141, and the metal cover plate 110 is placed on the ceramic base plate 320 via the sealing material 142. Has been. In the piezoelectric device 300, the metal cover plate 110 is placed on the center side of the ceramic base plate 320 with respect to the protrusions 325 via the sealing material 142. Therefore, the protrusion 325 suppresses the periphery of the metal cover body 110 and prevents the protrusion from being shifted and placed on the ceramic base plate 320. The piezoelectric device 300 is manufactured by the same method as the piezoelectric device 200. Similar to the piezoelectric device 200, the protrusion 325 suppresses the generation of defective products due to the displacement of the metal cover body 110 during the manufacturing process.

  In the piezoelectric device 300, the protrusion 325 may be formed in a wall shape so as to surround the dotted line 173 in FIG. At this time, since the sealing material 142 does not flow out of the protruding portion 325, the sealing material 142 is prevented from flowing into the break line 171 during the manufacturing of the piezoelectric device 300. Therefore, the division of the ceramic mother board is not hindered.

  As described above, the optimal embodiment of the present invention has been described in detail. However, as will be apparent to those skilled in the art, the present invention can be implemented with various modifications and variations within the technical scope thereof.

  For example, in the above-described embodiment, the case where the piezoelectric vibrating piece is an AT-cut quartz-crystal vibrating piece has been shown, but the same applies to a BT cut that vibrates in the thickness-slip mode or a tuning-fork-type quartz vibrating piece. Applicable. Further, the piezoelectric vibrating piece can be basically applied not only to a quartz material but also to a piezoelectric material including lithium tantalate, lithium niobate, or piezoelectric ceramic.

  In the above embodiment, the metal cover body 110 has the flange 114, but the metal cover body 110 may not have the flange 114. Furthermore, in step S503 shown in FIG. 4, a protrusion may be formed in addition to the annular groove. Thereby, the metal cover body 110 can be more reliably held.

DESCRIPTION OF SYMBOLS 100, 200, 300 ... Piezoelectric device 110 ... Metal cover body 111 ... Recessed part 112 ... Wall surface 113 ... Ceiling surface 114 ... Flange 120, 220, 320 ... Ceramic base plate 121 ... Connection electrode 122, 222 ... Wiring electrode 123, 229 ... Through Hole 124, 224 ... External electrode 125 ... Annular groove 130 ... Piezoelectric vibrating piece 131 ... Excitation electrode 132 ... Extraction electrode 141 ... Conductive adhesive 142 ... Sealing material 171 ... Break line 223 ... Castellation 225, 325 ... Projection 228 ... Insulating layer C120, C220 ... Ceramic fabric W120, W220 ... Ceramic mother board

Claims (10)

A metal base having a ceramic base plate including a first surface and a second surface opposite to the first surface, a piezoelectric vibrating piece placed on the first surface, and a wall surface extending from a ceiling surface so as to cover the piezoelectric vibrating piece A surface-mount type piezoelectric device having a metal cover body,
The ceramic base plate includes a protrusion formed around the first surface and protruding from the first surface; a connection electrode formed inside the protrusion and electrically connected to the piezoelectric vibrating piece; An external electrode formed on two surfaces, and a wiring electrode extending from the connection electrode to the external electrode,
The end of the wall surface of the metal cover body is disposed so as to contact the protrusion,
A piezoelectric device in which an end of the wall surface and the protrusion are sealed with a sealing material. The end of the metal cover body has a flange bent outward from the wall surface,
The piezoelectric device according to claim 1, wherein the flange is disposed inside the protrusion. The end of the metal cover body has a flange bent outward from the wall surface,
The piezoelectric device according to claim 1, wherein the flange is disposed outside the protrusion.   The said protrusion part is formed in the position which avoided the said wiring electrode, and an insulating layer is formed on the said wiring electrode located in the edge part of the said metal cover body. The piezoelectric device described. A metal base having a ceramic base plate including a first surface and a second surface opposite to the first surface, a piezoelectric vibrating piece placed on the first surface, and a wall surface extending from a ceiling surface so as to cover the piezoelectric vibrating piece A surface-mount type piezoelectric device having a metal cover body,
The ceramic base plate has an annular groove having a predetermined width formed around the first surface so as to be recessed from the first surface, and is formed in an annular shape of the annular groove and is electrically connected to the piezoelectric vibrating piece. A connection electrode, an external electrode formed on the second surface, and a wiring electrode extending from the connection electrode to the external electrode;
An end of the wall surface of the metal cover body is disposed in the annular groove,
A piezoelectric device in which an end of the wall surface and the annular groove are sealed with a sealing material. The end of the metal cover body has a flange bent outward from the wall surface,
The piezoelectric device according to claim 5, wherein a width of the flange is shorter than a predetermined width of the annular groove. A method for manufacturing a surface-mount type piezoelectric device having a metallic metal cover body having a wall surface extending from a ceiling surface,
In the sheet-like ceramic fabric including the first surface and the second surface on the opposite side, a break line for specifying the region of each ceramic base plate, and the corner of the region from the first surface to the second surface Forming a sheet-shaped ceramic mother substrate by firing after forming a through-hole penetrating and a protrusion protruding from the first surface on the first surface inside the break line;
A metal paste is applied and fired to form a connection electrode that is electrically connected to the piezoelectric vibrating piece inside the protrusion, an external electrode on the second surface, and a wiring electrode that extends from the connection electrode to the external electrode And a process of
Placing the piezoelectric vibrating piece on the connection electrode;
Applying a sealing material to the ceramic mother substrate;
Arranging the metal cover body along the protrusion, and sealing the metal cover body and the protrusion with the sealing material;
A method for manufacturing a piezoelectric device comprising:   The method of manufacturing a piezoelectric device according to claim 7, wherein the step of forming the ceramic mother substrate forms the break line, the through hole, and the protrusion by pressing a mold against the ceramic cloth. A method for manufacturing a surface-mount type piezoelectric device having a metallic metal cover body having a wall surface extending from a ceiling surface,
In the sheet-like ceramic fabric including the first surface and the second surface on the opposite side, a break line for specifying the region of each ceramic base plate, and the corner of the region from the first surface to the second surface A sheet-shaped ceramic mother substrate is formed by firing after forming a through-hole penetrating and an annular groove having a predetermined width formed in the first surface so as to be recessed from the first surface inside the break line. Forming, and
A metal paste is applied and fired to form a connection electrode electrically connected to the piezoelectric vibrating piece inside the annular groove, an external electrode on the second surface, and a wiring electrode extending from the connection electrode to the external electrode And a process of
Placing the piezoelectric vibrating piece on the connection electrode;
Applying a sealing material to the ceramic mother substrate;
Arranging the end of the metal cover body so as to enter the annular groove, and sealing with the end of the metal cover body, the annular groove and a sealing material;
A method for manufacturing a piezoelectric device comprising:   10. The method of manufacturing a piezoelectric device according to claim 9, wherein the step of forming the ceramic mother substrate forms the break line, the through hole, and the annular groove by pressing a mold against the ceramic material.