Power transistor module wiring structure

• US 5,616,955 A
• Filed: 04/22/1994
• Issued: 04/01/1997
• Est. Priority Date: 04/23/1993
• Status: Expired due to Term

• Current Assignee: Fuji Electric Company Limited (Fuji Electric Systems Company Limited)
• Original Assignee: Fuji Electric Company Limited (Fuji Electric Systems Company Limited)
• Inventors: Arai, Etsuo, Soyano, Shin, Watanabe, Manabu, Igarashi, Seiki, Yamada, Toshifusa
• Primary Examiner(s): BROWN, PETER T
• Application Number:
  US08/231,338
• Time in Patent Office: 1,075 Days
• Field of Search: 257/690, 257/691, 257/693, 257/698, 257/723, 257/724, 257/692, 257/797
• US Class Current: 257/690
• CPC Class Codes: H01L 2224/0603 Bonding areas having different sizes, e.g. different heights or widths
• CPC Class Codes: H01L 2224/45124 Aluminium (Al) as principal constituent
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48227 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/49111 the connectors connecting two common bonding areas, e.g. Litz or braid wires
• CPC Class Codes: H01L 2224/49113 the connectors connecting different bonding areas on the semiconductor or solid-state body to a common bonding area outside the body, e.g. converging wires
• CPC Class Codes: H01L 2224/49175 Parallel arrangements
• 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 25/18 the devices being of types provided for in two or more different subgroups of the same main group of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N
• 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 2924/00012 Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• 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 2924/01005 Boron [B]
• CPC Class Codes: H01L 2924/01006 Carbon [C]
• CPC Class Codes: H01L 2924/01013 Aluminum [Al]
• CPC Class Codes: H01L 2924/01019 Potassium [K]
• CPC Class Codes: H01L 2924/01029 Copper [Cu]
• CPC Class Codes: H01L 2924/01072 : Hafnium [Hf]
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/12041 : LED
• 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 2924/15747 : Copper [Cu] as principal constituent
• CPC Class Codes: H01L 2924/16152 : Cap comprising a cavity for hosting the device, e.g. U-shaped cap
• CPC Class Codes: H01L 2924/30107 : Inductance
• CPC Class Codes: H02M 7/003 : Constructional details, e.g. physical layout, assembly, wiring or busbar connections

Abstract

In packaged bridge circuit modules with power switching transistors such as IGBT'"'"'s, internal wiring inductance can cause switching voltage spikes and imbalance between switching transistors. Upon inclusion of suitably arranged and configured inductance elements, internal wiring inductance can produce a counter-electromotive force during switching. To this end, an internal connecting terminal may branch from an output terminal, a bridge-shaped internal connecting terminal may be connected between an emitter circuit pattern of one power transistor and a collector circuit pattern of another power transistor, or signal terminals as auxiliary emitter terminals of two power transistors may be connected to an inductance providing region in a current path of an emitter circuit pattern.

Claims

1. A power transistor module comprising:

a circuit substrate;

at least one pair of power transistor chips on the circuit substrate, respectively comprising a first (Tr1) and a second (Tr2) power transistor electrically interconnected in series as upper and lower arms of a bridge circuit;

first (D1) and second (D2) freewheel diodes connected antiparallel to the first (Tr1) and second (Tr2) power transistor, respectively;

separate first and second circuit patterns on the circuit substrate for the respective first (Tr1) and second (Tr2) power transistors, the first circuit pattern comprising a first emitter pattern and the second circuit pattern comprising a second collector pattern;

first (C1), second (C2E1) and third (E2) output terminals, and first (G1) and second (G2) gate terminals taken out from the first and second circuit patterns;

a bridge shaped internal connecting terminal interconnecting the first emitter pattern and the second collector pattern; and

a signal terminal (e1) connected to the internal connecting terminal as an auxiliary emitter terminal, at a point at which a desired internal wiring inductance is provided between the internal connecting terminal and the first emitter pattern.

2. The power transistor module according to claim 1, wherein the internal connecting terminal is loosely supported to allow its movement by a terminal block.

3. The power transistor module according to claim 1, further comprising an encapsulation, and gel filling material in which the internal connecting terminal is buried.

4. The power transistor module according to claim 1, wherein the respective freewheel diodes (D1 and D2) are on the same respective circuit patterns as the power transistors (Tr1 and Tr2).

5. A power transistor module comprising:

a circuit substrate;

at least one pair of power transistor chips on the circuit substrate, respectively comprising a first (Tr1) and a second (Tr2) power transistor electrically interconnected in series as upper and lower arms of a bridge circuit, and packaged as a minimum circuit;

first (D1) and second (D2) freewheel diodes connected antiparallel to the first (Tr1) and second (Tr2) power transistor, respectively;

a first collector pattern for the first power transistor

a circuit pattern on the circuit substrate, comprising a first emitter pattern for the first power transistor (Tr1) connected to a second collector pattern for the second power transistor (Tr2);

a second emitter pattern for the second power transistor (Tr2) on the circuit substrate;

first and second gate patterns for the first and second power transistors on the circuit substrate;

first (C1), second (C2E1) and third (E2) output terminals taken out from the first collector pattern, the circuit pattern and the second emitter pattern, respectively;

first (G1) and second (G2) gate terminals taken out from the first and second gate patterns, respectively;

an inductance providing region in a current path of one of the emitter patterns the current path having a width, and a slit dividing the width, forming the inductance providing region; and

signal terminals (e1 and e2) as auxiliary emitter terminals for each of the power transistors (Tr1 and Tr2), a first one of said signal terminals connected to the inductance providing region at a point at which a desired internal wiring inductance is provided.

6. The power transistor module according to claim 5, wherein the respective freewheel diodes (D1 and D2) are on the same respective collector patterns as the power transistors (Tr1 and Tr2).

7. A power transistor module comprising:

a circuit substrate;

at least one pair of power transistor chips on the circuit substrate, respectively comprising a first (Tr1) and a second (Tr2) power transistor electrically interconnected in series as upper and lower arms of a bridge circuit, and packaged as a minimum circuit;

first (D1) and second (D2) freewheel diodes connected antiparallel to the first (Tr1) and second (Tr2) power transistor, respectively;

a first collector pattern for the first power transistor (TE1) on the circuit substrate;

a circuit pattern on the circuit substrate, comprising a first emitter pattern for the first power transistor (Tr1) connected to a second collector pattern for the second power transistor (Tr2);

a second emitter pattern for the second power transistor (Tr2) on the circuit substrate;

first and second gate patterns for the first and second power transistors on the circuit substrate;

first (C1), second (C2E1) and third (E2) output terminals taken out from the first collector pattern, the circuit pattern and the second emitter pattern, respectively;

first (G1) and second (G2) gate terminals taken out from the first and second gate patterns, respectively;

an inductance providing region in a current path of one of the emitter patterns;

signal terminals (e1 and e2) as auxiliary emitter terminals for each of the power transistors (Tr1 and Tr2), a first one of said signal terminals connected to the inductance providing region at a point at which a desired internal wiring inductance is provided; and

marks along the inductance providing region indicating positions for connecting said first one of the signal terminals (e1 and e2).

8. The power transistor module according to claim 7, wherein the respective freewheel diodes (D1 and D2) are on the same respective collector patterns as the power transistors (Tr1 and Tr2).