JP2007013729A - Electrode structure of crystal oscillator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide electrode structure of a crystal oscillator sandwiched and sealed by plate-like members comprised of glass, etc. <P>SOLUTION: In the electrode structure of the crystal oscillator sealed by wafers comprised of members such as glass, respectively from the vertical directions so as to sandwich the wafers in which many crystal oscillators are formed, a drawing electrode is formed in a groove part of an inner side of a frame in which the crystal oscillators are formed and a drawing electrode is formed in a level difference part of the inner side of the frame in which the crystal oscillators are formed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

          The present invention relates to an electrode structure of a crystal resonator sandwiched and sealed between plate-like members made of glass or the like.

          Conventionally, after a crystal unit is mounted inside a package in order to eliminate the possibility of vibrations being suppressed by changes in ambient temperature / humidity and adhesion of fine foreign objects to the crystal unit base plate. Although used in a sealed manner, in order to respond to the rapid miniaturization and high frequency of electronic devices such as information terminals to be mounted, a crystal resonator is used instead of forming the package with the individual resonators described above. In the form of a wafer in which a large number of wafers are formed at the same time, after sealing using a plate-like member such as a wafer of the same shape from the top and bottom, each chip is cut into individual crystal units and cut into small chips. A technique for manufacturing a crystal resonator has been proposed.

          In the form of a wafer in which a large number of the above-mentioned crystal resonators are formed at the same time, sealing is performed using a plate-like member from the vertical direction using glass or the like for the plate-like member, and anodic bonding or direct bonding. It is possible to seal using a bonding method such as the above, and simultaneously seal a wafer on which a large number of crystal resonators are formed with another wafer from above and below so as to sandwich the wafer on which the crystal resonator is formed. It is well suited for efficiency.

          Until the frequency adjustment process of the crystal unit formed on the wafer, it is necessary to separate each electrode separately for each crystal unit. After the frequency adjustment step, the lead electrode and the crystal are again routed by vapor deposition. Conduction is made between the excitation electrode of the vibrator. In order to obtain good sealing at the subsequent wafer level by anodic bonding, it is necessary to produce the above-mentioned conduction in as small a range as possible without causing as many steps as possible in the deposited metal thin film. In addition, when direct bonding is used, a very high flatness of the material surface on which the bonding surface is formed is required. Therefore, good bonding at the wafer level can also be achieved by forming a metal thin film by vapor deposition on the bonding surface. For this reason, after the wafer is penetrated, the electrodes are actually routed on the side surfaces of the individual crystal resonators.

JP 7-154183 A Japanese Patent Laid-Open No. 2000-281459 JP 2001-177362 A Japanese Patent Laid-Open No. 2001-230651

          The applicant has not found any prior art documents related to the present invention other than the prior art documents specified by the prior art document information described above by the time of filing of the present application.

          However, in the wafer level sealing using anodic bonding after the frequency adjustment process, a slight level difference corresponding to the deposited film thickness is generated in the redeposited portion, so that the adhesion at the wafer level by anodic bonding is weak and sealed. There was a problem that said there was a risk that the stop would be incomplete.

          In addition, in wafer level sealing using direct bonding after the frequency adjustment step, a lead-in electrode is applied to the side surface of the crystal unit for routing the electrode. It depends greatly on the thickness dimension, and it is difficult to form a stable metal film on the side surface of the crystal unit by vapor deposition because it forms unevenness on the side surface of the crystal unit. There was a problem.

          The present invention has been made under the technical background as described above. Accordingly, the object of the present invention is to provide an electrode of a quartz crystal resonator sandwiched between plate members made of glass or the like and sealed. Is to provide a structure.

          In order to achieve the above object, the present invention provides an electrode structure of a crystal resonator that is sealed with a wafer made of a member such as glass from above and below so as to sandwich a wafer on which a large number of crystal resonators are formed. The lead electrode is formed in the inner surface groove portion of the frame body on which the crystal resonator is formed.

          In addition, a lead-out electrode is formed on a step portion on the inner surface of the frame body on which the crystal resonator is formed.

          According to the electrode structure of the crystal resonator of the present invention, when sealing using anodic bonding is performed, there is no step on the sealed bonding surface, and a crystal resonator capable of stable and highly reliable sealing is obtained. I can do it.

          In addition, when sealing using direct bonding is performed by the electrode structure of the crystal resonator of the present invention, the step of the bonding surface to be sealed and the metal film of the lead-in electrode can be stably formed, It is possible to obtain a crystal resonator that is sealed with high reliability.

          Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In addition, the same code | symbol in each figure shall show the same object.

          FIG. 1 is a schematic top perspective view of a crystal resonator 1 having an electrode structure according to the present invention as seen from the top surface direction. That is, the crystal unit 1 is formed in the electrode structure of the crystal unit 1 sealed with a wafer made of a member such as glass from above and below so as to sandwich a wafer on which a large number of crystal units 1 are formed. A lead electrode is formed in the inner surface groove portion 5 of the frame body 4. With the electrode structure of the crystal resonator 1 according to the present invention, when sealing using anodic bonding is performed, there is no step on the sealing surface to be sealed, and the crystal resonator is stably sealed with high reliability. 1 can be obtained. The groove portion is formed along the inner side surface of the frame body 4, and may be located on one side instead of the center as long as the position is within the range of the inner side surface. In this case also, the technical scope of the present invention Needless to say, it is included in Since the routing electrode is formed in the inner surface groove portion 5 of the frame body 4 on which the crystal resonator 1 is formed, the probe can be easily applied to the groove portion when adjusting the frequency, and the routing path of the frame body 4 By adopting the inner surface, the frequency measurement can be performed without adversely affecting the vibration of the crystal unit 1 without mechanically measuring the frequency in the vicinity of the output of the fine crystal unit 1. It plays.

          FIG. 2 is another schematic top perspective view of the crystal resonator 1 having the electrode structure of the present invention as seen from the top surface direction. In other words, the lead electrode is formed on the inner side surface step portion 7 of the frame body 4 on which the crystal unit 1 is formed. Needless to say, a step may be included, and this case is also included in the technical scope of the present invention. When sealing using direct bonding is performed by the electrode structure of the crystal resonator 1 of the present invention, the step of the bonding surface to be sealed and the metal film of the lead-in electrode can be stably formed, It is possible to obtain a crystal resonator 1 that is highly sealed.

          FIG. 3 is a schematic top perspective view of the crystal unit 1 having the electrode structure of the present invention shown in FIG. 1 as viewed from above, showing a state before frequency adjustment and a state after frequency adjustment and before sealing. is there.

          FIGS. 4A and 4B are schematic cross-sectional views as viewed from the side when the groove 4 is provided in the frame 4 of the crystal resonator 1 having the electrode structure of the present invention (cross-sectional view 2) and when there is a step (cross-sectional view 1). is there. The portion connected to the frame body is a coupling portion between the crystal body 1 and the frame body 4 through which an output signal of the crystal body 1 located inside the frame body 4 passes.

          FIG. 5 is a schematic top perspective view of the quartz crystal resonator 1 having a conventional electrode structure as seen from above, showing a state before frequency adjustment and a state after frequency adjustment and before sealing. Conventionally, after sealing the wafer at the wafer level using anodic bonding after the frequency adjustment process, a slight step corresponding to the deposited film thickness occurs at the redeposited portion, so that the adhesion at the wafer level by anodic bonding is weak. There was a problem that sealing might be incomplete.

1 is a schematic top perspective view of a crystal resonator having an electrode structure according to the present invention as viewed from above. FIG. 6 is another schematic top perspective view of a crystal resonator having an electrode structure according to the present invention as viewed from above. FIG. 2 is a schematic top perspective view of the crystal resonator having the electrode structure of the present invention shown in FIG. 1 as viewed from above, showing a state before frequency adjustment and a state after frequency adjustment and before sealing. FIG. 3 is a schematic cross-sectional view seen from the side direction when the groove of the crystal unit having the electrode structure of the present invention has a groove and when the frame has a step. It is the outline top perspective view which looked at the crystal oscillator which has the conventional electrode structure from the upper surface direction which shows the state before frequency adjustment, and the state after frequency adjustment and before sealing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Crystal oscillator 4 Frame 5 Inner surface groove part 6 Leading electrode 7 Inner surface level | step difference part

Claims (2)

In the electrode structure of the crystal resonator that is sealed with a wafer made of a member such as glass from above and below so as to sandwich a wafer on which a large number of crystal resonators are formed,
An electrode structure of a crystal resonator, wherein a lead electrode is formed in an inner surface groove portion of a frame body on which the crystal resonator is formed.           2. The electrode structure for a crystal resonator according to claim 1, wherein a lead-out electrode is formed on an inner surface step portion of the frame on which the crystal resonator is formed.

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