JP5061046B2 - Quartz crystal resonator, electronic component, and method for manufacturing element for crystal resonator - Google Patents

Description

  The present invention relates to a technique for manufacturing a crystal resonator element using an AT-cut crystal piece.

  Conventionally, as a method of obtaining a large number of rectangular crystal pieces used for a crystal resonator from an AT-cut crystal wafer, a method of cutting by dicing so that long sides are formed along the X axis is known. A method is known in which an excitation electrode is formed in the central region, and an extraction electrode is formed on the −X side (minus side in the X axis). On the other hand, the present inventor is considering forming the outer shape of the crystal piece by wet etching. FIG. 17 is a diagram showing this state, and a plurality of rectangular sections 101 are formed on the wafer W1, and a crystal piece supported by the wafer W1 is formed in each of the sections 101, and an excitation electrode is formed on the crystal piece. The crystal resonator element is formed by forming the lead electrode.

  The frequency characteristics of the crystal resonator are determined by the thickness of the crystal piece of the crystal resonator element. In recent years, the required frequency characteristics are from 10 MHz to several hundred MHz, and the thickness of the crystal piece at that time is from several μm to several tens of μm. For this reason, it is ideal to form a crystal piece using the wafer W1 having the above-described thickness. However, if the wafer W1 is thin, problems such as strength occur and it becomes very difficult to perform the work, and productivity is increased. There is a problem that decreases. Therefore, when forming crystal pieces, a wafer W1 having a thickness that is easy to work, for example, 300 μm is used, and a plurality of sections 101 for forming crystal pieces are provided on the wafer W1, and each section 101 is etched to form a recess 110. The crystal piece is formed by adjusting the thickness of the bottom of the recess 110.

  However, the recess 110 is formed such that its side wall is inclined as shown in FIG. Since AT-cut quartz has anisotropy and etching proceeds with an individual inclination on each crystal axis of the quartz, the side wall of the recess 110 becomes an inclined surface, and the area of one section 101 is In addition to the area of the bottom surface 111 necessary for forming the crystal piece and the resist mask region necessary for etching, it is necessary to determine the region of the inclined surface of the side wall of the recess 110. In FIG. 18, for convenience of explanation, only nine concave portions 110 on the wafer W1 are shown, and the other portions are omitted.

  Therefore, as shown in FIG. 18B, between the two recesses 110 arranged in the X-axis direction, the mask region 120 where a resist film serving as an etching mask is formed and spreads from the bottom surface 111 of both recesses 110. Are formed, and a trapezoidal side region CX is formed. Further, as shown in FIG. 18C, an inclined surface that spreads from the mask region 120 to the bottom surface 111 of one of the recesses 110 is formed between the two recesses 110 aligned in the Z-axis direction. A region CZ is formed. Since a crystal piece cannot be formed in the side regions CX and CZ including the inclined surfaces, it is ideal to reduce the length of the side regions CX and CZ, that is, the length of the bottom of the trapezoid as much as possible. It is. However, when the number of the sections 101 is increased, the number of the side regions CX and CZ increases in proportion to the number of the sections 101. Therefore, in the conventional wafer W1, the productivity increase rate is suppressed, and the productivity can be improved. As a result, it was difficult to reduce the unit price per crystal piece.

  On the other hand, in Patent Document 1, as a method for improving the utilization efficiency of the semiconductor seed crystal substrate with respect to the area of the substrate and the utilization efficiency of the material, a cylindrical rod as a raw material of the substrate is cut obliquely according to the crystal orientation, The matter to increase the area of the substrate by forming the substrate is described. However, even if an AT-cut quartz wafer W1 is formed by the method of Patent Document 1, the point that the side wall of the recess 110 becomes an inclined surface due to the anisotropy of quartz when etching is performed is the same as described above. It is impossible to solve the problem.

Japanese Patent Laying-Open No. 2005-116661 (paragraph numbers 0029 to 0031, 0099)

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a method for manufacturing a crystal resonator element capable of improving the productivity per wafer, and the crystal resonator element. An object of the present invention is to provide a crystal resonator and a crystal oscillator.

In the method for manufacturing a crystal resonator element of the present invention,
In a method of forming a rectangular array of quartz resonator elements on a quartz substrate,
Etching with an etchant from one side of the quartz substrate using a mask to form a first row of recesses each having a rectangular planar shape and a cross-sectional shape of an inverted trapezoid due to the anisotropy of quartz, and its thickness A step of obtaining a rectangular element formation region in which is adjusted,
Etching with an etching solution using a mask from the other side of the quartz substrate, and alternately arranged with respect to the first recesses, the planar shape is rectangular and the cross-sectional shape is inverted trapezoid due to the anisotropy of quartz. Forming a row of recesses of 2 to obtain a rectangular element formation region whose thickness is adjusted;
Forming an electrode in the element formation region to obtain a crystal resonator element,
The first concave portion and the second concave portion are characterized in that inclined side surfaces overlap in the thickness direction.

The quartz substrate is an AT-cut quartz substrate, and the element formation region is arranged in the X-axis direction or the Z-axis direction. Crystal resonator of the present invention also includes a container sealing the quartz crystal element manufactured by the respective manufacturing process, provided in the container, and a terminal portion electrically connected to the front Symbol electrodes, the It is characterized by having prepared. According to another aspect of the invention, there is provided an electronic component including the above-described crystal resonator and an oscillation circuit for causing the crystal resonator to oscillate.

  According to the present invention, etching is performed on one surface side and the other surface side of the quartz substrate, and the first recesses are alternately arranged with respect to the first recesses and the first recesses each having a rectangular planar shape and an inverted trapezoidal cross-sectional shape. When forming the row | line | column of the 2nd recessed part arranged, each recessed part is formed so that the inclined side surfaces of a 1st recessed part and a 2nd recessed part may overlap in thickness direction. Thus, in the present invention, the side surface of the inclined first recess and the side surface of the second recess that cannot form the crystal piece overlap each other, that is, the side region of the first recess and the second recess overlap. Can be made. Therefore, the length of the lateral region between the first recess and the second recess can be shortened, and the number of holes in which crystal pieces are formed is more than that when a plurality of recesses are provided only on one side. Therefore, the productivity of crystal pieces per wafer can be improved.

[First Embodiment]
A wafer W relating to a crystal substrate for forming a crystal piece according to the present invention will be described with reference to FIGS. A wafer W shown in FIG. 1A is a quartz substrate formed of AT-cut quartz. A front side section 20 for forming a crystal piece 51 (see FIG. 8 to be described later) is disposed on the wafer surface 10 corresponding to one surface side of the wafer W. A plurality of, for example, ten front side sections 20 are continuously arranged in the Z direction in the figure. In addition, a front side partition row 20a serving as an element formation region is formed in which adjacent front side sections 20 are arranged so that the respective sections do not overlap each other. The front side partition rows 20a are arranged in five rows at a certain interval in the X direction shown in the figure. From the region between the front side partition rows 20a and the front side partition row 20a formed at the −X side end− The area on the X side is the facing area 11.

  Further, as shown in FIG. 1B, a back side section 40 for forming a crystal piece 51 is disposed on the wafer back surface 30 corresponding to the other surface side of the wafer W at a position facing the facing region 11. 5 rows of back side division rows 40a are formed in the X direction shown in the drawing in the X direction, which is an element formation region in which the divisions 40 are arranged in the same manner as the front side divisions 20 of the front side division row 20a. A region between the back side partition rows 40a and a region on the + X side of the back side partition row 40a formed at the end on the + X side become the facing region 31 of the front side partition 20.

  As shown in FIG. 2, when the thickness of the wafer W is adjusted to a thickness at which the crystal piece 51 can obtain a desired frequency characteristic in the front side section 20 indicated by a broken line, a rectangular first recess is formed by etching. 21 is formed. In addition to the bottom portion 22 which is a region for forming the crystal piece 51, the first concave portion 21 has a first side wall 23 having an inclined surface in the illustrated + X direction when viewed from the center of the front side section 20, and a first side wall 23 in the illustrated -X direction. 2 has a second side wall 24 having an inclined surface different from the one side wall 23, a third side wall 25 having an inclined surface in the -Z direction in the figure, and a fourth side wall 26 in the + Z direction in the figure. As shown in FIG. 3 which shows a cross section taken along the line AA, the cross-sectional shape on the X axis in the depth direction of the first recess 21 is an inverted trapezoidal shape. In the region outside the edge of the first recess 21, a metal film 2 and a resist film 3 (see FIG. 6 described later) are formed when etching is performed, and the metal film 2 and the resist film 3 form the first recess. This is a mask region 12 in which a mask pattern for forming 21 is formed.

  Further, in the back side section 40, a second concave portion 41 indicated by a two-dot chain line in FIG. 2 is formed in the same manner as the first concave portion 21, and the second concave portion 41 is formed in addition to the bottom portion 42 which is a region where the crystal piece 51 is formed. The first side wall 43, the second side wall 44, the third side wall 45, the fourth side wall 46, and the mask region 32 having the same inclination angle as the first recess 21. As shown in FIG. 3, the first concave portion 21 and the second concave portion 41 are arranged so that the bottom portions 22 and 42 do not overlap the first side walls 23 and 43 and the second side walls 24 and 44 facing each other in the thickness direction of the wafer W. They are formed alternately in the + X direction. In FIG. 2, for convenience of explanation, only the six first recesses 21 and one second recess 41 on the wafer W are shown as in FIG. 18, and other descriptions are omitted. In the second recess 41, the first side wall 43 is the side wall in the -X direction, the second side wall 44 is the side wall in the + X direction, the third side wall 45 is the side wall in the + Z direction, and the fourth side wall 46 is in the -Z direction. It becomes a side wall. The reason for this will be described below.

  As described above, the AT-cut quartz has anisotropy, and the etching proceeds with an individual inclination on each crystal axis of the quartz, so that the etching is oblique from the wafer surface 10 toward the bottom 22. Proceed to. On the wafer back surface 30, the inclination at which etching proceeds toward the bottom 42 is reversed on each crystal axis as viewed from the wafer surface 10. Therefore, in the adjacent front side section 20 and back side section 40, the slopes of the side walls of the first concave portion 21 and the second concave portion 41 formed are interchanged, and the first side walls 23, 43 having the same inclination angle as shown in FIG. Alternatively, the second side walls 24 and 44 face each other. At this time, the slopes of the first side walls 23 and 24 and the second side walls 24 and 44 are formed so that an error in the angle is about 0 to 1 degree when either the bottom part 22 or the bottom part 42 is used as a reference. Therefore, the opposing side walls are formed to be substantially parallel. Therefore, in the wafer W of this embodiment, the regions where the first side walls 23 and 43 and the second side walls 24 and 44 are formed overlap in the front side section 20 and the back side section 40. As shown in FIG. 4 which shows a cross section taken along the line BB in FIG. 2, the front side partition row 20a and the back side partition are arranged so that either one of the first recesses 21 or the second recesses 41 is arranged in the Z-axis direction. Since the row 40a is disposed, the cross-sectional shape thereof is the same as that of the conventional wafer W1.

  Compared with the wafer W of this embodiment and the conventional wafer W1 shown in FIG. 18B, as shown in FIG. 5, in the case of the wafer W1 in which three bottom portions 111 are arranged, the distance of the side region CX is The width B of the mask region 120, the width b1 of the inclined surface on the + X side corresponding to the first side wall of the concave portion 110, and the width b2 of the inclined surface on the −X side corresponding to the second side wall become B + b1 + b2. Since there are two locations, the distance of all lateral regions C1 in the X-axis direction is 2 (B + b1 + b2). On the other hand, in the wafer W in which the bottom portion 42 is formed between the bottom portions 22 of the present embodiment, the distance of the side surface region CX1 where the first side walls 23 and 43 are opposed is the width b1 of the first side walls 23 and 43. The total thickness α1 of the quartz crystal that separates the first recess 21 and the second recess 41 is b1 + α1, and the distance of the side region CX2 that the second side walls 24, 44 face each other is the distance between the second side walls 24, 44. Since the total thickness α2 of the quartz that separates the width b2 from the first recess 21 and the second recess 41 is b2 + α2, the distance of all the lateral regions C2 in the X-axis direction is b1 + b2 + α1 + α2.

  Here, α1 + α2 approximates to 2B, so if α1 + α2 is replaced with 2B, the distance of all side regions C2 becomes 2B + b1 + b2, and compared to all side regions C1 of the conventional wafer W1, only b1 + b2 is in the direction of all side regions C2. Becomes shorter. That is, in the wafer W, the distance of the entire lateral region C2 that cannot be used to form the crystal piece 51 is shorter than that of the wafer W1, and accordingly, the X axis when the bottom portions 22 and 42 are arranged in total is arranged. The distance in the direction can be shortened by about b1 + b2 compared to the conventional wafer W1. As the number of bottom portions 22 and 42 increases, the distance in the X-axis direction required compared to the conventional wafer W1 can be shortened, and the number of bottom portions 22 and 42 can be increased accordingly. As a result, for example, when the wafer W of the present embodiment shown in FIG. 1 is compared with the conventional wafer W1 shown in FIG. 17, the total number of front side partition rows 20a and back side partition rows 40a is 2 in the wafer W compared to the wafer W1. The number can be increased, and the total number of front side sections 20 and back side sections 40 can be increased by 20.

  For each of the reasons described above, in the wafer W of the present embodiment, the etching is performed on the wafer front surface 10 and the wafer back surface 30 so that the first recesses 21 each having a rectangular planar shape and an inverted trapezoidal cross-sectional shape, and the first When forming the rows of the second recesses 41 alternately arranged with respect to the recesses 21 in the front surface partition row 20a and the back surface partition row 40a, the same inclination of both the first recess 21 and the second recess 41 Recesses are formed so that the first sidewalls 23 and 43 or the second sidewalls 24 and 44 having the same overlap with each other in the thickness direction of the wafer W. The bottom portions 22 and 42 are formed so as not to overlap the first side walls 23 and 43 and the second side walls 24 and 44 in the thickness direction of the wafer W. Thereby, in the wafer W of the present embodiment, the inclined first side walls 23 and 42 or the second side walls 24 and 44 where the crystal piece 51 cannot be formed are overlapped with each other between the wafer front surface 10 and the wafer back surface 30. Only the lateral region C2 of the first recess 21 and the second recess 41 can be overlapped in a manner that does not inhibit the formation. Accordingly, the number of the first concave portions 21 and the second concave portions 41 in which the crystal pieces 51 are formed can be increased as compared with the case where a plurality of the first concave portions 21 are provided on only one side, and the number of the first concave portions 21 and the second concave portions 41 can be increased. The number of manufactured crystal pieces 51 can be improved.

  Next, the manufacturing process of the wafer W of this embodiment will be described with reference to FIGS. In the present embodiment, etching is performed on the front side section 20 and the back side section 40 of the wafer W forming the crystal piece 51, and the crystal piece 51 formed with the thickness of the bottom portions 22 and 42 has a desired frequency characteristic. Decrease until possible. In this thickness adjustment, the front side section 20 and the back side section 40 forming the crystal piece 51 are etched, and the thickness of the bottom portions 22 and 42 is set so that the natural frequency of the formed crystal piece 51 becomes a desired frequency. Adjust to thickness.

  Specifically, as shown in FIGS. 6A and 6B, a metal film 2 made of Cr (chrome) and Au (gold) and a resist film 3 are formed on the wafer front surface 10 and the wafer rear surface 30, respectively. Then, a resist mask is formed by photolithography, and the metal film 2 is etched by a KI (potassium iodide) solution to form a laminated mask corresponding to the front side section 20. Then, the wafer W is immersed in a hydrofluoric acid solution as shown in FIG. 6C, and the wafer W is etched to form a first recess 21 as shown in FIG. The resist film 3 is peeled off and the frequency of the bottom portion 22 is confirmed by a probe (not shown). As a result, as shown in FIGS. 6E and 6F, first concave portions 21 are formed in the plurality of surface sections 20 of the wafer surface 10. 6 (a) to 7 (e) schematically show the cross section of the wafer W at the position indicated by the arrow AA, as in FIG. 3, and FIG. 6 (f) shows the position at the arrow AA. The wafer surface 10 is shown.

  Next, as shown in FIG. 7A, the wafer W is inverted, the metal film 2 made of Cr (chrome) and Au (gold) is formed on the wafer front surface 10, the wafer back surface 30, and the first recess 21, and the resist film 3. Then, a resist mask is formed by photolithography, and the metal film 2 is etched by a KI (potassium iodide) solution to form a laminated mask corresponding to the back side section 40. Then, the wafer W is immersed in a hydrofluoric acid solution as shown in FIG. 7B, and the wafer W is etched to form a second recess 41 as shown in FIG. The resist film 3 is peeled off and the frequency of the bottom 42 is confirmed by a probe (not shown). As a result, as shown in FIGS. 7D and 7E, corresponding first recesses 21 are formed in the plurality of surface sections 20 of the wafer surface 10. 7A to 7D schematically show a cross section of the wafer W at the position indicated by the arrow AA, as in FIG. 3, and FIG. 7E shows the position at the arrow AA. The wafer surface 10 is shown.

  Through the above steps, the wafer W of the present embodiment is formed as a wafer W in which the first concave portions 21 and the second concave portions 41 are alternately formed in the X direction as shown in FIGS. 3 and 7D. Since the first concave portion 21 and the second concave portion 41 are formed by etching, the first sidewalls 23 and 43 and the second sidewall 24 having the same inclination automatically using the anisotropy of quartz. , 44 are formed to face each other. In addition, although the 1st recessed part 21 and the 2nd recessed part 41 are formed in a separate process, as embodiment of this invention, a wafer is match | combined with the shape of the 1st recessed part 21 shown, for example in FIG.6 (b). In the step of peeling the metal film 2 and the resist film 3 on the front surface 10, the resist film 3 and the metal film 2 on the wafer back surface 30 are peeled off according to the shape of the second recess 41, and the first recess 21 and the second recess 41 are formed. The formation may be performed simultaneously.

  Next, the crystal piece 51 and the crystal resonator element 50 using the crystal piece 51 from the wafer W of this embodiment will be described with reference to FIGS. The crystal resonator element 50 is formed from the wafer W by the following procedure. First, after forming the first concave portion 21 and the second concave portion 41, the metal film 4 and the resist film 5 are formed on the wafer front surface 10 and the wafer back surface 30 as shown in FIG. An outer shape mask pattern 68 for forming the outer shape of the crystal piece 51 is formed on the resist film 5 by photolithography and etching using the KI solution described above. Then, the wafer W is etched along the outer shape mask pattern 68 to form a crystal piece 51 from the wafer W as shown in FIG. 8B, and the remaining resist film 4 and metal film 5 are peeled off. At this time, the crystal piece 51 is connected and supported on the wafer W by a connection support portion (not shown).

  When the crystal piece 51 is formed, the metal film 6 and the resist film 7 are formed on the entire surface of the crystal piece 51 as shown in FIG. 8C, and the crystal resonator element 50 is etched by photolithography and KI solution. Mask patterns corresponding to the shapes of the excitation electrode 52 and the extraction electrode 53 are formed. Then, as shown in FIG. 8 (d), the metal film 6 is etched to form the excitation electrode 52 and the extraction electrode 53, and the resist film 7 is removed and the connection support portion is cut by laser dicing to obtain individual pieces. The crystal resonator element 50 is formed. As shown in FIG. 9, the crystal resonator element 50 has excitation electrodes 52 formed on opposing surfaces of a crystal piece 51, and lead electrodes 53 connected to the respective excitation electrodes 52. From the front surface where 52 is formed to the back surface, it is formed so as to pass through a common side surface. 8A to 8D schematically show the cross section of the wafer W at the position indicated by the arrow A-A as in FIG.

  Next, a crystal resonator 70 in which the crystal resonator element 50 formed from the wafer W of this embodiment is incorporated will be described with reference to FIG. As shown in FIG. 10, the crystal resonator 70 is formed by enclosing the crystal resonator element 50 in the exterior body 71. In the crystal resonator 70, the crystal resonator element 50 is fixed so that the lead electrode 53 is electrically connected to the pair of attachment electrodes 72 provided in the exterior body 71 by the conductive adhesive 73. Then, the external electrode 74 under the exterior body 71 connected to the attachment electrode 72 via the wiring is connected to an electrode of an electronic component such as an oscillator, thereby electrically connecting the crystal resonator element 50 and the electronic component inside. It becomes possible to connect.

[Second Embodiment]
A second embodiment of the quartz plate forming quartz substrate of the present invention will be described with reference to FIGS. A wafer W2 according to the second embodiment shown in FIG. 11 shows a front side partition row 20b which is an element formation region formed by continuously arranging a plurality of, for example, eight wafers in the X direction shown in the drawing, instead of the front side partition row 20a. For example, six rows are arranged at regular intervals in the Z direction, and the region between the front side partition rows 20b and the region on the −X side from the −X side front side row 20b in the Z direction become the facing region 11. . Then, at the position facing the facing region 11 on the wafer back surface 30, the back side partition row 40b, which is an element formation region formed by arranging the back side partition 40 in the same manner as the front side partition row 20b, has a constant interval in the Z direction in the figure. Six rows are provided, and the region between the back side partition rows 40b and the region on the −X side from the −Z side back side partition row 40b in the Z direction become the facing region 31 of the front side partition row 20.

  Accordingly, in the wafer W2, as shown in FIGS. 12 to 14, the front side section 20 indicated by a broken line is etched in order to adjust the thickness of the wafer W2 so that the crystal piece 51 can obtain a desired frequency characteristic. Thus, the first recess 21 having the same shape as that of the first embodiment is formed, and the second recess 41 indicated by a two-dot chain line in FIG. Here, FIG. 13 shows the cross section taken along the line AA shown in FIG. 12 as in FIG. 3, and FIG. 14 shows the cross section taken along the line BB as shown in FIG. Since the front-side partition row 20b and the back-side partition row 40b are arranged so that either one of the first recess 21 or the second recess 41 is arranged in plural, the cross-sectional shape thereof is the same as that of the conventional wafer W1.

  On the other hand, as shown in FIG. 14, the third side walls 25 and 45 or the fourth side walls 26 and 46 having the same inclination of the first concave portion 21 and the second concave portion 41 adjacent to each other in the Z-axis direction shown in FIG. In addition, the third side walls 25 and 45 having an inclination are formed so as to overlap. Compared with the wafer W2 of this embodiment and the conventional wafer W1 shown in FIG. 18C, as shown in FIG. 15, in the case of the wafer W1 in which three bottom portions 111 are arranged, the distance of the side region CZ is Since the width B of the mask region 120 and the width b3 of the inclined surface on the + Z side corresponding to the thirteenth side wall of the recess 110 are summed to be B + b3, and there are two side regions CZ, the width of all the side regions C3 in the Z-axis direction is The distance is 2 (B + b3). On the other hand, in the wafer W in which the bottom portion 42 is formed between the bottom portions 22 of the present embodiment, the distance of the side surface region CZ1 where the third side walls 25 and 45 face each other is the width b3 of the third side walls 25 and 45. The total thickness α1 of the quartz that separates the first concave portion 21 and the second concave portion 41 is b3 + α1, and the distance between the side surface region CZ2 where the fourth side walls 26 and 46 are opposed is the first concave portion 21 and the second concave portion 41. Since the thickness of the quartz that separates the recess 41 is α2, the distance of the entire lateral region C4 in the Z-axis direction is b3 + α1 + α2.

  Here, α1 + α2 approximates to 2B. Therefore, if α1 + α2 is replaced with 2B, the distance of all lateral regions C4 becomes 2B + b3, and compared to the entire lateral region C3 of the conventional wafer W1, only b3 is closer to all lateral regions C4. Becomes shorter. That is, in the wafer W, the distance of the entire lateral region C4 that cannot be used to form the crystal piece 51 is shorter than that of the wafer W1, and accordingly, the Z axis when the bottom portions 22 and 42 are arranged in total is arranged. The distance in the direction can be shortened by about b3 compared to the conventional wafer W1. As the number of bottom portions 22 and 42 increases, the distance in the X-axis direction required compared to the conventional wafer W1 can be shortened, and the number of bottom portions 22 and 42 can be increased accordingly. As a result, for example, when the wafer W of the present embodiment shown in FIG. 11 is compared with the conventional wafer W1 shown in FIG. 17, the total number of the front side partition row 20b and the back side partition row 40b is compared with the wafer W1. Two can be increased, and the total number of front side sections 20 and back side sections 40 can be increased by 16. Therefore, also in the wafer W2 of the present embodiment, the number of the front side sections 20 and the back side sections 40 as in the wafer W can be increased as compared with the case where the formation sections are disposed only on one side. The productivity of the crystal pieces 51 per wafer W2 to be formed can be improved.

[Other Embodiments]
In the wafer of the present invention, since the bottoms of the first recess and the second recess are the crystal resonator element forming regions, the side walls of the first recess and the second recess are used as they are as the crystal oscillator exterior body. It can also be used as a part of For example, as shown in FIG. 16A, in addition to the wafer W of the first embodiment, an upper wafer W3 and a lower wafer W4 made of AT-cut quartz are prepared. A sealing portion 81 that seals the first recess 21 is formed at a position corresponding to the first recess 21 in the upper wafer W3, and a support portion 82 that supports the crystal piece 51 is formed between the sealing portions 81. Yes. Further, in the lower wafer W4, a sealing portion 91 that seals the second recess 41 is formed at a position corresponding to the second recess 41, and a support portion 92 that supports the crystal piece 51 is formed between the sealing portions 91. Has been.

  Then, as shown in FIG. 16B, the wafer W in a state where the crystal resonator element 50 is connected and supported, and the upper wafer W3 and the lower wafer W4 are attached to the support portions 82 and 92 by an adhesive or the like, for example. The composite wafer W5 is formed by bonding the electrode 53 corresponding to the formed attachment electrodes 83 and 93 in such a manner that they contact each other. Then, by cutting the composite wafer W5 at a position corresponding to the first recess 21 and the second recess 41 along the cut position line D shown in FIG. 16C, for example, by dicing such as laser dicing, as shown in FIG. As described above, the crystal resonator 701 can be manufactured. In addition, when forming the crystal piece 51, it is not restricted to an etching, For example, you may form the crystal piece 51 by cutting by dicing, such as laser dicing. Further, instead of the wafer W, the wafer W2 of the second embodiment can be used.

  In the present invention, a first concave portion and a second concave portion for forming a crystal piece are provided on both the front and back surfaces of a wafer which is a quartz substrate, and a region where a side wall having both slopes is formed is formed on the wafer. Since the number of crystal pieces that can be manufactured from one crystal substrate is increased by overlapping in the thickness direction, the opposing side walls of the adjacent first recess and the second recess always have the same inclination. For example, in the first embodiment, the first side wall 23 of the first concave portion 21 and the second side wall 44 of the second concave portion 41 and the second side wall 24 of the first concave portion 21 and the second side wall are not necessary. You may form so that the 1st side wall 43 of the recessed part 41 may oppose. Moreover, in this embodiment, the front side division rows 20a and 20b and the back side division rows 40a and 40b are all formed by arranging the same number of front side divisions 20 and back side divisions 40. However, as an embodiment of the present invention, for example, It is also possible to arrange a front side division row or a back side division row with a reduced number of divisions in the surplus area of the wafer after arranging the front side division rows 20a and 20b and the back side division rows 40a and 40b.

It is a schematic plan view of the wafer W of this embodiment. It is the 1st explanatory view for explaining the relation between the 1st crevice and the 2nd crevice of wafer W of this embodiment. It is the 2nd explanatory view for explaining the relation between the 1st crevice and the 2nd crevice of wafer W of this embodiment. It is the 3rd explanatory view for explaining the relation between the 1st crevice and the 2nd crevice of wafer W of this embodiment. It is a comparison figure for demonstrating the comparison with the wafer W of this embodiment, and the conventional wafer W1. It is the 1st explanatory view for explaining the process of forming the 1st crevice in wafer W of this embodiment. It is the 2nd explanatory view for explaining the process of forming the 2nd crevice in wafer W of this embodiment. It is explanatory drawing for demonstrating the process of forming a crystal piece from the wafer W of this embodiment. It is a perspective view for demonstrating the element for crystal oscillators of this embodiment. It is sectional drawing for demonstrating an example of the crystal oscillator of this embodiment. It is a schematic plan view of the wafer W2 in the 2nd Embodiment of this invention. It is the 1st explanatory view for explaining the relation between the 1st crevice and the 2nd crevice of wafer W2. It is the 2nd explanatory view for explaining the relation between the 1st crevice and the 2nd crevice of wafer W2. It is the 3rd explanatory view for explaining the relation between the 1st crevice and the 2nd crevice of wafer W2. It is a comparison figure for demonstrating the comparison with the wafer W2 and the conventional wafer W1. It is explanatory drawing for demonstrating the other Example of the crystal oscillator based on this invention. It is a schematic plan view of the conventional wafer W1. It is explanatory drawing for demonstrating the relationship between the hole of the conventional wafer W1, and the wafer W. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Wafer surface 11 Facing area 20 Front side division 20a, 20b Front side division row | line | column 21 1st recessed part 22 Bottom 23, 43 1st side wall 24, 44 2nd side wall 25, 45 3rd side wall 26, 46 4th side wall 30 Wafer back surface 31 Facing Region 40 Back surface partition 40a, 40b Back surface partition row 41 Second recess 42 Bottom 50 Crystal resonator element 51 Crystal piece 52 Excitation electrode 53 Extraction electrode 70 Crystal resonator W, W1, W2 Wafer

Claims (4)

In a method of forming a rectangular array of quartz resonator elements on a quartz substrate,
Etching with an etchant from one side of the quartz substrate using a mask to form a first row of recesses each having a rectangular planar shape and a cross-sectional shape of an inverted trapezoid due to the anisotropy of quartz, and its thickness A step of obtaining a rectangular element formation region in which is adjusted,
Etching with an etching solution using a mask from the other side of the quartz substrate, and alternately arranged with respect to the first recesses, the planar shape is rectangular and the cross-sectional shape is inverted trapezoid due to the anisotropy of quartz. Forming a row of recesses of 2 to obtain a rectangular element formation region whose thickness is adjusted;
Forming an electrode in the element formation region to obtain a crystal resonator element,
The method for manufacturing a crystal resonator element, wherein the first concave portion and the second concave portion have inclined side surfaces that overlap each other in the thickness direction.   2. The method for manufacturing a crystal resonator element according to claim 1, wherein the crystal substrate is an AT-cut crystal substrate, and the element formation regions are arranged in the X-axis direction or the Z-axis direction. A container in which the quartz resonator element manufactured by the manufacturing method according to claim 1 is sealed;
Provided on the container, crystal oscillator, characterized by comprising a terminal portion electrically connected to the front Symbol electrodes, the.   An electronic component comprising the crystal resonator according to claim 3 and an oscillation circuit for causing the crystal resonator to oscillate.

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