Acceleration sensor

• US 6,435,028 B1
• Filed: 08/01/2000
• Issued: 08/20/2002
• Est. Priority Date: 02/25/2000
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Nagahara, Teruaki
• Primary Examiner(s): MOLLER, RICHARD ALAN
• Application Number:
  US09/630,429
• Time in Patent Office: 749 Days
• Field of Search: 735/140.1, 734/88
• US Class Current: 73/514.01
• CPC Class Codes: B81C 1/0023 Packaging together an electronic processing unit die and a micromechanical structure die MEMS packages B81B7/0032; MEMS packaging processes B81C1/00261
• CPC Class Codes: G01P 1/023 for acceleration measuring devices
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/3025 Electromagnetic shielding

Abstract

The size reduction of an acceleration sensor having an acceleration detecting chip (ACa) and a signal processing chip (SCa), can be attained with an improvement in arrangement of both chips. Specifically, the acceleration detecting chip (ACa) is disposed in a through-hole (HL1) formed in the signal processing chip (SCa). A cap (CPa) is provided in order to prevent resin flowing into an acceleration detecting part (AS), when forming a resin encapsulation package.

Claims

1. An acceleration sensor comprising:

an acceleration detecting chip including an acceleration detecting part having a movable part that shifts depending on acceleration, so that said chip outputs an electrical signal depending on the shift of said movable part;

a signal processing chip having a through-hole and a circuit for processing said electrical signal from said acceleration detecting chip; and

a die pad to which said acceleration detecting chip and said signal processing chip are adhered, wherein

said acceleration detecting chip is disposed in said through-hole of said signal processing chip on said die pad.

2. The acceleration sensor according to claim 1, further comprising:

a cap adhered to said signal processing chip so as to cover said through-hole; and

a resin encapsulation package covering at least an adhesive portion between said signal processing chip and said cap.

3. The acceleration sensor according to claim 2, wherein

said acceleration detecting chip further comprises an electrode for outputting said electrical signal, and

said signal processing chip further comprises an electrode connected via a bonding wire to said electrode of said acceleration detecting chip.

4. The acceleration sensor according to claim 2, wherein,

said cap is a plate-like and has a notch about its periphery;

an electrical connection between said acceleration detecting chip and said signal processing chip is established at said notch; and

said notch is filled with an insulating material.

5. The acceleration sensor according to claim 1, further comprising:

a cap adhered to said acceleration detecting chip so as to cover said acceleration detecting part of said acceleration detecting chip; and

a resin encapsulation package covering at least an adhesive portion between said acceleration detecting chip and said cap.

6. The acceleration sensor according to claim 5, wherein

said acceleration detecting chip further comprises an electrode for outputting said electrical signal, and

said signal processing chip further comprises an electrode connected via a bonding wire to said electrode of said acceleration detecting chip.