JP5362293B2 - Manufacturing method of component with built-in piezoelectric element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To print discrimination symbols on a wafer in a lump without damaging a surface of a piezoelectric element built-in component made of a transparent quartz material such as a crystal and a glass material. <P>SOLUTION: A component includes a built-in piezoelectric element and shields the piezoelectric element from an external atmosphere, and is made of the transparent material such as a crystal and a glass material, and a discrimination symbol S is displayed on the component surface by sputtering or photolithography. Further, a wafer method is used to display a plurality of discrimination symbols S in a lump on the wafer by sputtering or photolithography. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a piezoelectric element built-in component made of a transparent multilayer quartz material, and a discrimination symbol printing method for collectively printing discrimination symbols on a cover portion and a base portion at a wafer level.

  Conventionally, after manufacturing a piezoelectric element built-in part, for example, a crystal resonator, a discriminator such as a manufacturer name, frequency, manufacturing lot number, QR code, bar code, etc. is printed on the surface of the part one by one with ink. . However, depending on the surface state of the printing surface, there are cases in which the ink is poorly loaded, which causes problems such as a decrease in printing yield, poor solvent resistance, and print peeling.

  Therefore, in order to solve such a problem, a predetermined discrimination symbol is marked on the surface by laser processing to maintain a more reliable and reliable printing state.

  For example, as shown in FIG. 5, a conventional crystal resonator 40 includes a ceramic base 42 on which a crystal plate on which electrodes are formed is mounted, and an external connection terminal 48 disposed on the bottom surface thereof. 42 is covered with a metal cover 44 and hermetically sealed. A laser beam L is emitted from a laser irradiation device, and a discrimination symbol such as a manufacturing lot number is engraved on the surface of the metal cover 44 for display (printing) S.

However, in the case of laser processing, the surface of the product is cut and printed, and accordingly, the product to be printed needs to be thick, and this type of piezoelectric element built-in part, for example, a crystal resonator is downsized and reduced in height. There arises a problem that does not conform to. Also, quartz materials such as quartz and glass materials are to be printed as discriminating symbols. For example, when printing is performed on the cover part and the base part by laser processing, these members are transparent. There was a possibility that the member may permeate and damage other members.
Japanese Utility Model Publication No. 5-48428 JP 2004-194046 A

  The problem to be solved by the present invention is that a discriminating symbol is displayed at the same time as performing another process of the wafer processing process without causing damage to the surface of the piezoelectric element built-in component made of a quartz material such as a transparent crystal or glass material. It is to print on the top.

  In order to solve the above-described problems, the present invention is a component that includes a piezoelectric element inside and shields the piezoelectric element from the external atmosphere, and the component is made of a crystal or glass material, and is sputtered on the surface of the component. A discrimination symbol is displayed by photolithography. In addition, a plurality of discriminating symbols are collectively displayed on the wafer by sputtering or photolithography using a wafer method.

  The discrimination symbol can be clearly and collectively printed on the wafer, and the discrimination symbol for each piece can be omitted, so that the number of manufacturing steps can be greatly reduced.

  Hereinafter, an embodiment of a method for displaying a discrimination symbol on a quartz component according to the present invention will be described with reference to FIGS.

  First, a quartz component, for example, a component with a built-in piezoelectric element (quartz crystal resonator), which is a target for printing (marking) a discrimination symbol of the quartz component of the present invention, will be described with reference to FIGS.

  As shown in FIG. 1A, a piezoelectric element built-in component 1 includes a base part 2 made of a transparent quartz material, for example, quartz or glass, and a piezoelectric element part 3 laminated on the upper surface of the base part 2 also made of a transparent material. And a cover part 4 made of a transparent material covered with the piezoelectric element part 3. Here, a cavity 5 having a concave section is formed at the center of the base portion 2, and an IC chip 6 is flip-chip mounted on the bottom surface 5 a of the cavity 5 via bumps 7. An external connection terminal 8 is disposed on the bottom of the base portion 2.

  Similarly, as shown in FIG. 1B, the crystal resonator 1a includes a base portion 2 made of a transparent quartz material, for example, quartz or glass, and a piezoelectric element portion laminated on the upper surface of the base portion 2 also made of a transparent material. 3 and a cover portion 4 made of a transparent material covered with the piezoelectric element portion 3.

  A cavity 9 having a concave cross section is formed at the center of the cover portion 4.

  Here, in more detail, the piezoelectric element built-in component 1 shown in FIG. 1 is applied to the cover portion 4 (FIG. 2A), the piezoelectric element portion 3 (FIG. 2B), and the base portion 2 (FIG. 2C), respectively. Decompose and explain.

  First, the cover part 4 is configured as shown in FIGS. 1 and 2A, and has a cavity 4b at the center thereof, and a metal thin film 4a is formed on the upper surface thereof.

  2B, the crystal element 31 has a substantially square shape in plan view, and has excitation electrodes 32 on both principal surfaces thereof with the central portion serving as a vibration region. . An extraction electrode 33 extends from the excitation electrode 32 to both sides of one end, and further extends to opposite main surfaces by electrode through holes 34. An annular electrode 36 for bonding is formed on the outer edge of the piezoelectric element portion 3, and a ground electrode 35 having electrode through holes 34 on both sides of the other end portion is formed.

  Further, as shown in FIGS. 1 and 2C, the base portion 2 has a cavity 5 formed in the center thereof, and an IC chip 6 is flip-chip mounted on the bottom surface of the cavity 5 via bumps. . Further, a metal thin film 2 a is formed on the upper surface of the base portion 2, and a pair of ground electrodes 22 and a pair of crystal terminals 21 are disposed. An annular electrode 23 for bonding is formed on the outer edge of the base portion 2.

  Thus, in the piezoelectric element built-in component of the present invention, the cover 4, the piezoelectric element portion 3, and the base portion 2 are made of a transparent material, and both sides of one end portion of the crystal piece 31 from which the extraction electrode 33 extends and the base portion 2. After positioning the crystal terminal 21, the piezoelectric element portion 3, the ground electrodes 22 and 35 of the base portion 2, and the annular electrodes 23 and 36, the crystal piece 31 and the cover portion 4, They are joined and laminated with a eutectic alloy interposed between them.

  In particular, the characteristic feature of the method for printing a discrimination symbol on a quartz part according to the present invention is that, as shown in FIG. 4, a single wafer W constituting a cover part or a base part is separated from a wafer processing step. For example, when the electrode of the cover part or base part is formed at the same time, the discriminating symbols such as the manufacturer name, frequency, and manufacturing lot number are character strings, and the code display (bar code, QR code, etc.) that can be read by electronic equipment Printed and displayed with embossed characters (symbols) or extracted characters (symbols).

  As a display method by printing, first, metal thin films 2a and 4a having a predetermined thickness (the same thickness as the electrode, for example, 100 to 2000 mm of Cr / Au) are formed by vapor deposition on the wafer surface, and sputtering, photo The above-mentioned predetermined discrimination symbol is marked by lithography.

  In particular, the printing method by photolithography / etching has higher processing accuracy of marking than that by ink or laser, and a small pattern can be printed as a marking. For this reason, quartz parts are always required to be miniaturized, and printing by photolithography / etching is effective.

  On the other hand, in the case of laser printing, since marking is performed by machining the product, a predetermined thickness is required for the parts to be printed. In photolithography / etching, a metal thin film is first deposited on the wafer surface by vapor deposition. Then, this thin film is simply patterned to print a discrimination symbol. Therefore, the discriminating symbol printing method of the present invention does not scrape the product like laser processing, so that printing that sufficiently satisfies the requirements for downsizing and low profile of a piezoelectric element built-in part, for example, a crystal resonator. Become a method.

  Further, in the method for printing a discrimination symbol on the piezoelectric element built-in part of the present invention, as shown in FIG. 3, dicing is performed from the wafer constituting the cover part, the base part or the piezoelectric element part to the individual piezoelectric element built-in parts. When the piezoelectric element built-in component composed of the cover portion 4, the piezoelectric element portion 3, and the base portion 2 is configured by dividing the disc, etc., the discrimination symbol S (for example, NT001) is changed to FIG. As shown in FIG. 3A, the metal film 4a of the cover portion 4 of the piezoelectric element built-in component is displayed as a raised character (symbol) (FIG. 3A) or a blank character (symbol) (FIG. 3B). . Further, as shown in FIGS. 3C and 3D, the raised character (symbol) (FIG. 3C) or the extracted character (symbol) (symbol) ( Each is configured as shown in FIG.

  The piezoelectric element built-in component of the present invention and its identification symbol printing method can be widely used for piezoelectric components made of a transparent material such as crystal or glass material.

It is a longitudinal cross-sectional view of the piezoelectric element built-in component (FIG. 1 (a)) and (FIG. 1 (b)) used as the printing object of the Example of the printing method of the discrimination symbol to the piezoelectric element built-in component of this invention. FIG. 2A is an exploded view of the piezoelectric element built-in component shown in FIG. 1, FIG. 2A shows the cover part, FIG. 2B shows the piezoelectric element part, and FIG. The base parts are respectively shown. 3A and 3B are perspective views of the piezoelectric element built-in component shown in FIG. 1, in which FIG. 3A shows a state in which a discrimination symbol is printed on the cover portion, and FIG. 3B shows the cover portion. FIG. 3 (c) shows a state in which a discrimination symbol is printed out with characters, and FIG. 3 (c) shows a state in which a discrimination symbol is printed on the base portion, and FIG. 3 (d) shows a discrimination symbol on the base portion. The state in which the characters are printed with the characters omitted is shown. FIG. 5 is a plan view showing a state where a plurality of discrimination symbols are printed on the wafer in a lump collectively on the piezoelectric element built-in component according to the present invention. FIG. 10 is a perspective view of a conventional example in which a discrimination symbol is printed on a crystal resonator by laser processing.

Explanation of symbols

1 Built-in piezoelectric element (quartz crystal)
2 Base part 2a Metal thin film 3 Piezoelectric element part 4 Cover part 4a Metal thin film 4b Cavity 5 Cavity 6 IC chip 7 Bump 8 External connection terminal

Claims (3)

A piezoelectric element built-in component comprising a piezoelectric element inside, shielding the piezoelectric element from the external atmosphere, and made of crystal or glass material,
The piezoelectric element built-in component is a piezoelectric element built-in part, a cover part placed on the upper surface of the piezoelectric element built-in part, and a base part which is disposed on the bottom surface of the piezoelectric element built-in part and constitutes an external connection terminal surface In a method for manufacturing a piezoelectric element built-in component consisting of:
Using the wafer method, a step of forming a metal thin film on the wafer which constitutes the cover portion,
And a step of displaying a plurality of discriminating symbols on the metal thin film formed on the wafer by photolithography at once. 2. The method for manufacturing a piezoelectric element built-in component according to claim 1 , wherein the cover part and the base part displaying the discrimination symbol are laminated with the piezoelectric element built-in part and then individually cut to manufacture the piezoelectric element built-in component. . The piezoelectric element built parts, the method for manufacturing a piezoelectric element built-in part according to claim 1 or 2, characterized in that a quartz oscillator.