Pressure sensing semiconductor device comprising a semiconductor chip which has a diaphragm formed with piezoresistance

• US 6,401,542 B1
• Filed: 07/11/2000
• Issued: 06/11/2002
• Est. Priority Date: 01/24/2000
• Status: Expired due to Fees

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Kato, Hajime
• Primary Examiner(s): OEN, WILLIAM L
• Application Number:
  US09/614,211
• Time in Patent Office: 700 Days
• Field of Search: 737/15, 737/16, 737/17, 737/18, 737/19, 737/20, 737/21--27, 737/54, 737/56, 257/414, 257/415, 257/417, 257/418, 257/420, 438/50, 438/51
• US Class Current: 73/721
• CPC Class Codes: G01L 19/0038 being part of the housing other details about the housing G01L19/14
• CPC Class Codes: G01L 19/148 Details about the circuit board integration, e.g. integrated with the diaphragm surface or encapsulation
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• 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 2924/16151 Cap comprising an aperture, e.g. for pressure control, encapsulation
• CPC Class Codes: H01L 2924/16152 Cap comprising a cavity for hosting the device, e.g. U-shaped cap
• CPC Class Codes: H01L 2924/3025 Electromagnetic shielding

Abstract

A down-sized pressure sensing semiconductor device with improved EMI tolerance as compared with conventional ones is achieved. A metal substrate (11) has a through hole (12), in which a cylinder (9b) of a pressure leading-in tube (9) is inserted, and is fixed to a flange (9a) of the pressure leading-in tube (9). A control circuit component (13) for controlling a semiconductor chip (1) is disposed on the metal substrate (11). On the metal substrate (11), a connector electrode (14) is further provided which establishes electrical connections between the pressure sensing semiconductor device and external circuits. Further, a metal cover (17) in the shape of a connector leading to external circuits is soldered to the metal substrate (11) to cover the semiconductor chip (1) and the control circuit component (13) together with the metal substrate (11). The cover (17) is electrically connected to a conductive wire (e.g., a ground wire) formed on the metal substrate (11).

Claims

1. A pressure sensing semiconductor device comprising:

a semiconductor chip having a diaphragm formed with piezoresistance;

a seating having a first main surface to which said semiconductor chip is fixed and in which a through hole is located at a point facing said diaphragm;

a pressure leading-in tube of metal having a cylinder leading to said through hole in said seating and a flange having a first main surface fixed to a second main surface of said seating on the opposite side of said first main surface of said seating; and

a metal substrate having a through hole in which said cylinder is inserted and a control circuit electrically connected to said semiconductor chip, said metal substrate being jointed to said flange by welding.

2. The device according to claim 1, wherein

said pressure leading-in tube further has a protrusion formed on a second main surface of said flange on the opposite side of said first main surface of said flange.

3. The device according to claim 1, further comprising:

a metal cover fixed on said metal substrate to cover said semiconductor chip and said control circuit together with said metal substrate.

4. The device according to claim 1, further comprising:

a glass cap fixed on said semiconductor chip and having a closed chamber to form a pressure standardized chamber on said diaphragm.

5. The device according to claim 1, wherein

said metal substrate further includes:

a mounting part for mounting said pressure sensing semiconductor device to a target; and

a connector electrode for establishing electrical connections between said pressure sensing semiconductor device and an external circuit.

6. A pressure sensing semiconductor device comprising:

a semiconductor chip having a diaphragm formed with piezoresistance;

a seating having a first main surface to which said semiconductor chip is fixed and in which a through hole is located at a point facing said diaphragm;

a pressure leading-in tube of metal having a cylinder leading to said through hole in said seating and a flange having a first main surface fixed to a second main surface of said seating on the opposite side of said first main surface of said seating; and

a metal substrate having a through hole in which said cylinder is inserted, a control circuit electrically connected to said semiconductor chip, and a conductive pattern formed on a main surface facing said flange, said metal substrate being jointed to said flange by soldering said conductive pattern to a second main surface of said flange on the opposite side of said first main surface of said flange.

7. The device according to claim 6, wherein

at least either of said second main surface of said flange and a surface of said conductive pattern is plated to improve joint adhesion.

8. The device according to claim 6, further comprising:

a metal cover fixed on said metal substrate to cover said semiconductor chip and said control circuit together with said metal substrate.

9. The device according to claim 6, further comprising:

a glass cap fixed on said semiconductor chip and having a closed chamber to form a pressure standardized chamber on said diaphragm.

10. The device according to claim 6, wherein

said metal substrate further includes:

a mounting part for mounting said pressure sensing semiconductor device to a target; and

a connector electrode for establishing electrical connections between said pressure sensing semiconductor device and an external circuit.

11. A pressure sensing semiconductor device comprising:

a semiconductor chip having a diaphragm formed with piezoresistance;

a seating which has a through hole located at a point facing said diaphragm and to which said semiconductor chip is fixed;

a pressure leading-in tube leading to said through hole;

a substrate having a control circuit electrically connected to said semiconductor chip; and

a glass cap disposed on said semiconductor chip and having a closed chamber to form a pressure standardized chamber on said diaphragm.