Power module

• US 20040179341A1
• Filed: 03/29/2004
• Published: 09/16/2004
• Est. Priority Date: 05/16/2000
• Status: Active Grant

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation), Ryoden Semiconductor System Engineering Corporation
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation), Ryoden Semiconductor System Engineering Corporation
• Inventors: Nakajima, Dai, Yoshimatsu, Naoki, Yoshida, Takanobu, Koga, Masuo, Majumdar, Gourab, Fukada, Masakazu, Kimoto, Nobuyoshi
• Granted Patent: US 6,900,986 B2
• Time in Patent Office: Days
• US Class Current: 361/704
• CPC Class Codes: H01L 2224/32225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/45124 Aluminium (Al) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/4811 Connecting to a bonding area of the semiconductor or solid-state body located at the far end of the body with respect to the bonding area outside the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/49109 outside the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/73265 Layer and wire connectors
• CPC Class Codes: H01L 23/057 the leads being parallel to the base
• CPC Class Codes: H01L 23/50 for integrated circuit devices, e.g. power bus, number of leadsH01L23/482 - H01L23/498 take precedence
• CPC Class Codes: H01L 23/60 Protection against electrostatic charges or discharges, e.g. Faraday shields
• CPC Class Codes: H01L 24/45 of an individual wire connector
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 24/49 of a plurality of wire connectors
• CPC Class Codes: H01L 25/072 the devices being arranged next to each other
• 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 2924/01007 Nitrogen [N]
• CPC Class Codes: H01L 2924/01013 Aluminum [Al]
• CPC Class Codes: H01L 2924/01014 Silicon [Si]
• CPC Class Codes: H01L 2924/01015 : Phosphorus [P]
• CPC Class Codes: H01L 2924/01023 : Vanadium [V]
• CPC Class Codes: H01L 2924/01074 : Tungsten [W]
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/1305 : Bipolar Junction Transistor [BJT]
• CPC Class Codes: H01L 2924/13055 : Insulated gate bipolar transistor [IGBT]
• CPC Class Codes: H01L 2924/1532 : the connection portion being formed on the die mounting surface of the substrate
• CPC Class Codes: H01L 2924/16152 : Cap comprising a cavity for hosting the device, e.g. U-shaped cap
• CPC Class Codes: H01L 2924/19041 : being a capacitor
• CPC Class Codes: H01L 2924/19107 : off-chip wires
• CPC Class Codes: H01L 2924/30105 : Capacitance
• CPC Class Codes: H01L 2924/30107 : Inductance
• CPC Class Codes: H01L 2924/3025 : Electromagnetic shielding
• CPC Class Codes: H01L 2924/351 : Thermal stress
• CPC Class Codes: H02M 7/003 : Constructional details, e.g. physical layout, assembly, wiring or busbar connections

Abstract

A power module includes a box-shaped smoothing capacitor (20) for smoothing a DC supply voltage to be externally applied to a power semiconductor device (5). The smoothing capacitor (20) is in contact with a side surface of a case frame (6) including a side (along which an N-terminal (8N) and a P-terminal (8P) are arranged) of a top surface of the case frame (6), and has a top surface level with the top surface of the case frame (6). An N-electrode (21N) and a P-electrode (21P) of the smoothing capacitor (20) are disposed on the top surface of the smoothing capacitor (20) and in proximity to the N-terminal (8N) and the P-terminal (8P) of a power module body portion (99), respectively. The power module can reduce a circuit inductance, is reduced in size and weight, and has good resistance to vibration.

Claims

1. A power module comprising:

a substrate with a power semiconductor device mounted thereon;

a case having an interior in which said substrate is disposed;

an N-terminal and a P-terminal arranged along a first side of a main surface of said case and electrically connected to said power semiconductor device; and

a smoothing capacitor having a first electrode connected to said N-terminal and a second electrode connected to said P-terminal for smoothing a voltage to be externally supplied to said power semiconductor device,

wherein said smoothing capacitor has a main surface level with said main surface of said case, and is disposed in contact with a side surface of said case including said first side of said main surface of said case, and

wherein said first electrode and said second electrode are disposed on said main surface of said smoothing capacitor and in proximity to said N-terminal and said P-terminal, respectively.

2. The power module according to claim 1,

wherein said smoothing capacitor comprises:

an enclosure;

a plurality of capacitor elements disposed in said enclosure, each of said plurality of capacitor elements having a first electrode abutting against said first electrode of said smoothing capacitor and a second electrode abutting against said second electrode of said smoothing capacitor; and

a hold-down plate for pressing said plurality of capacitor elements against said enclosure to fix said plurality of capacitor elements in said enclosure.

3. The power module according to claim 2,

wherein said enclosure has a single heat sink for dissipating heat generated by said plurality of capacitor elements.

4. The power module according to claim 2,

wherein at least one of said first and second electrodes of said smoothing capacitor has elasticity.

5. The power module according to claim 1,

wherein said smoothing capacitor is a ceramic capacitor.

6. A power module comprising:

a substrate with a power semiconductor device mounted thereon;

a case having an interior in which said substrate is disposed, said case including a predetermined recess in an outer surface thereof;

an N-terminal and a P-terminal disposed on side walls of said recess and electrically connected to said power semiconductor device; and

a smoothing capacitor fitted in said recess and having a first electrode positioned to correspond to said N-terminal and a second electrode positioned to correspond to said P-terminal for smoothing a voltage to be externally supplied to said power semiconductor device.

7. The power module according to claim 6,

wherein there is provided at least one of a first electrically conductive elastic member between said first electrode and said N-terminal and a second electrically conductive elastic member between said second electrode and said P-terminal.

8. The power module according to claim 6,

wherein said smoothing capacitor is a ceramic capacitor.

9. A power module comprising:

a first substrate with a power semiconductor device mounted thereon;

a second substrate with a control circuit for controlling said power semiconductor device formed thereon;

a smoothing capacitor electrically connected to said power semiconductor device for smoothing a voltage to be externally supplied to said power semiconductor device; and

a case including a case frame and a case lid, said case having an interior in which said first substrate, said second substrate and said smoothing capacitor are disposed.

10. The power module according to claim 9,

wherein said smoothing capacitor is disposed on said case lid.

11. The power module according to claim 9, further comprising

a shield plate disposed between said first substrate and said second substrate and fixed to said case frame,

wherein said smoothing capacitor is disposed on said shield plate.

12. The power module according to claim 11, further comprising

a thermally conductive sheet formed between said shield plate and said smoothing capacitor.

13. The power module according to claim 11,

wherein said shield plate is a metal shield plate.

14. The power module according to claim 9,

wherein said smoothing capacitor is disposed on said first substrate.

15. The power module according to claim 14,

wherein said first substrate and said smoothing capacitor are made of the same material.

16. The power module according to claim 9, further comprising

a heat sink for dissipating heat generated from said first substrate, said first substrate and said case frame being placed on said heat sink,

wherein said smoothing capacitor is disposed on said heat sink.

17. The power module according to claim 9,

wherein said smoothing capacitor is a ceramic capacitor.