METHOD OF MANUFACTURING CRYSTAL UNIT

• US 20080271307A1
• Filed: 05/02/2008
• Published: 11/06/2008
• Est. Priority Date: 05/04/2007
• Status: Abandoned Application

• Current Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Inventors: PARK, Jang Ho
• Application Number:
  US12/114,368
• Publication Number:
  US 20080271307A1
• Time in Patent Office: Days
• US Class Current: 29/594
• CPC Class Codes: H01L 2224/81 using a bump connector
• CPC Class Codes: H01L 2224/97 the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01R 43/02 for soldered or welded connections
• CPC Class Codes: Y10T 29/49005 Acoustic transducer
• CPC Class Codes: Y10T 29/49169 Assembling electrical component directly to terminal or elongated conductor
• CPC Class Codes: Y10T 29/49798 Dividing sequentially from leading end, e.g., by cutting or breaking

Abstract

There is provided a method of manufacturing a crystal unit, the method including: providing a package wafer including a plurality of connecting terminals each having top and bottom ends exposed to top and bottom surfaces of the package wafer; mounting a crystal blank having an excitation electrode formed thereon on at least one of the connecting terminals of the package wafer; depositing and bonding a cap wafer having a cavity with an open bottom therein on the top surface of the package wafer where the crystal blanks are mounted; and cutting bonding portions between the package wafer and the cap wafer into a plurality of individual crystal units. The crystal unit is reduced in thickness and size, and can be manufactured in mass production and packaged in a single process, thereby increasing lead time and process efficiency.

Claims

1. A method of manufacturing a crystal unit, the method comprising:

providing a package wafer comprising a plurality of connecting terminals each having top and bottom ends exposed to top and bottom surfaces of the package wafer;

mounting a crystal blank having an excitation electrode formed thereon on at least one of the connecting terminals of the package wafer;

depositing and bonding a cap wafer having a cavity with an open bottom therein on the top surface of the package wafer where the crystal blanks are mounted; and

cutting bonding portions between the package wafer and the cap wafer into a plurality of individual crystal units.

2. The method of claim 1, wherein the providing a package wafer comprises:

forming a pattern mask for terminal connection on the bottom surface of the package wafer;

etching the package wafer to form a blind via with a closed top;

applying a conductive metal layer on an inner surface of the blind via; and

polishing the top surface of the wafer package to expose the top of the blind via.

3. The method of claim 2, wherein the applying a conductive metal layer comprises filling a conductive filler in the blind via.

4. The method of claim 1, wherein the package wafer is provided on the top surface thereof with a lower pattern for terminal connection disposed on the top end of the internal and external connecting terminal, and the lower pattern for terminal connection is provided on an outer periphery thereof with a bonding pattern bonded to the cap wafer.

5. The method of claim 1, wherein the crystal blank mounted on the package wafer has a frequency adjusted by partially removing the excitation electrode formed on the top surface of the package wafer by dry or ion beam etching.

6. The method of claim 1, wherein the cap wafer has a bonding upper pattern formed uninterruptedly along an outer periphery of the cavity.

7. The method of claim 6, wherein the bonding upper pattern is protectively enclosed by a protective mask before the cavity is formed in the bottom surface of the cap wafer.

8. The method of claim 1, wherein the bonding the package wafer and the cap wafer comprises thermally bonding the bonding lower pattern formed on the top surface of the package wafer and the bonding upper pattern formed on the bottom surface of the cap wafer together.

9. The method of claim 8, wherein the bonding upper and lower patterns are formed of an uninterrupted pattern surrounding an outer periphery of the crystal blank.

10. The method of claim 2, wherein the polishing the top surface of the wafer package is performed after the cavity is formed.

11. The method of claim 2, wherein the polishing the top surface of the wafer package is performed when the package wafer and the cap wafer are bonded together.

12. The method of claim 8, wherein the thermally bonding upper and lower patterns is the step of bonding at a low temperature using a low melting point metal.