US 6,144,046 A · Power inverter having series connection of semiconductor devices each having an inverse parallel connection of an insulated gate bipolar transistor and a diode

Abstract

An inverter apparatus constituted by one or more series connections of plural semiconductor devices each having a pair consisting of an insulated gate bipolar transistor, and a diode, both of which are in a reverse parallel connection with each other, wherein the resistivity of the base layer of the lowest impurity concentration in the diode is lower than that of the base layer of the lowest impurity concentration in the insulated gate bipolar transistor, and wherein a breakdown voltage of said insulated gate bipolar transistor at the time of switching from a conduction state to a blocking state is lower than a breakdown voltage of said insulated gate bipolar transistor and said diode at the time of the blocking state.

Claims22

Dependent claims

An inverter apparatus comprising:

a plurality of semiconductor devices connected in series in one phase, at least one of the semiconductor devices being constituted by a pair consisting of an insulated gate bipolar transistor and a diode, both of which are in a reverse parallel connection;
wherein the resistivity of a base layer of lowest impurity concentration in said diode is lower than that of a base layer of lowest impurity concentration in said insulated gate bipolar transistor;
and
wherein the breakdown voltage of said insulated gate bipolar transistor at the time of switching from a conduction state to a blocking state is lower than the breakdown voltage of said insulated gate bipolar transistor and the breakdown voltage of said diode at the time of said blocking state.

1 more element

An inverter apparatus comprising:

a plurality of semiconductor devices connected in series in one phase, at least one of the semiconductor devices being constituted by a pair consisting of an insulated gate bipolar transistor and a diode, wherein
(1) said insulated gate bipolar transistor comprises:
a first main surface and a second main surface;
a first area of a first conductive type, exposed to said first main surface;
a second area of a second conductive type, adjacent to said first area and having an impurity concentration lower than that of said first area;
a third area of the second conductive type, adjacent to said second area and having an impurity concentration lower than that of said second area and being exposed to the second main surface;
a fourth area of the first conductive type selectively formed in said second main surface and having an impurity concentration higher than that of said third area;
a fifth area of the second conductive type, selectively formed in the second main surface and having an impurity concentration higher than that of said fourth area, an insulated gate being formed on the third, fourth and fifth areas through an insulation film;
a first main electrode in low ohmic contact with the first area;
and
a second main electrode which shorts said fourth and fifth areas on the second main surface;
and
(2) said diode has one and other main surfaces and comprises:
a sixth area of the second conductive type, exposed to said one main surface;
a seventh area of the second conductive type adjacent to said sixth area and having an impurity concentration lower than that of said sixth area;
an eighth area of the first conductive type, adjacent to said seventh area and having an impurity concentration which is higher than that of said seventh area and being exposed to said other main surface;
a third main electrode in low ohmic contact with said sixth area;
and
a fourth main electrode in low ohmic contact with said eighth area;
wherein said first main electrode and said third main electrode are connected to each other, and said second main electrode and said fourth main electrode are connected to each other;
wherein the resistivity of the seventh area in said diode is lower than that of the third area of said insulated gate bipolar transistor;
and
wherein the breakdown voltage of the insulated gate bipolar transistor at the time of switching from a conduction state to a blocking state is lower than the breakdown voltage of said insulated gate bipolar transistor and the breakdown voltage of said diode at the time of said blocking state.

20 more elements

An inverter apparatus comprising a plurality of semiconductor devices connected in series in one phase, at least one of the semiconductor devices being constituted by a pair consisting of an insulated gate bipolar transistor and a diode, both of which are in reverse parallel connection in one module, wherein

(1) said insulated gate bipolar transistor comprises:
a first area of a first conductive type, exposed to a first main surface;
a second area of a second conductive type, adjacent to said first area and having an impurity concentration lower than that of said first area;
a third area of the second conductive type, adjacent to said second area and having an impurity concentration lower than that of said second area and having a surface exposed to a second main surface;
a fourth area of the first conductive type, selectively formed in said second main surface in said third area and having an impurity concentration higher than that of said third area;
a fifth area of the second conductive type, selectively formed in the second main surface in said fourth area and having an impurity concentration higher than that of said fourth area;
a first main electrode in low ohmic contact with the first area;
and
a second main electrode short-circuiting said fourth and fifth areas on the second main surface;
and
(2) said diode has one main surface and other main surface and comprises:
a sixth area of the second conductive type, exposed to the one main surface;
a seventh area of the second conductive type, adjacent to said sixth area and having an impurity concentration lower than that of said sixth area;
an eighth area of the first conductive type, adjacent to said seventh area and having an impurity concentration higher than that of said seventh area;
a third main electrode in low ohmic contact with the sixth area;
and
a fourth main electrode in low ohmic contact with said eighth area;
wherein said first and third main electrodes are connected to each other, and said second and fourth main electrodes are connected to each other;
wherein the resistivity of the seventh area in said diode is lower than that of the third area of said insulated gate bipolar transistor;
and
wherein the breakdown voltage of the insulated gate bipolar transistor at the time of switching from a conduction state to a blocking state is lower than the breakdown voltage of said insulated gate bipolar transistor and the breakdown voltage of said diode at the time of the blocking state.

18 more elements

An inverter apparatus comprising:

a plurality of semiconductor devices connected in series in one phase, at least one of the semiconductor devices being constituted by
(1) an insulated gate bipolar transistor having a semiconductor body with a first main surface and a second main surface;
a first area of first conductive type, exposed to said first main surface;
a second area of second conductive type, adjacent to said first area and having an impurity concentration lower than that of said first area;
a third area of the second conductive type, adjacent to said second area and having an impurity concentration lower than the second area;
a fourth area of the first conductive type, selectively formed in said third area and having an impurity concentration higher than that of said third area;
a fifth area of the second conductive type, selectively formed in said fourth area and having an impurity concentration higher than that of said fourth area;
a first main electrode in low ohmic contact with the first area;
a second main electrode which shorts said fourth and fifth areas on the second main surface;
an insulated gate formed on said third, fourth and fifth areas, exposed to said second main surface, through an insulation film;
and
(2) a diode having a semiconductor body with one main surface and other main surface;
a sixth area of the second conductive type, exposed to the one main surface;
a seventh area of the second conductive type, adjacent to said sixth area and having an impurity concentration lower than that of said sixth area;
an eighth area of the first conductive type, adjacent to said seventh area and having an impurity concentration higher than that of said seventh area;
a third main electrode in low ohmic contact with said sixth area;
and
a fourth main electrode in low ohmic contact with said eighth area;
wherein said first and said third main electrodes are connected to each other, and said second and said fourth main electrodes are connected to each other;
wherein the resistivity of the third area of said insulated gate bipolar transistor is in the range from n/17 to n/6 .OMEGA..multidot.cm, and the resistivity of the seventh area of said diode is in the range from n/25 to n/17 .OMEGA..multidot.cm;
wherein the thickness of the third area of said insulated gate bipolar transistor is in the range from n/10.5 to n/7.5 .mu.m;
and wherein the thickness of the seventh area in said diode is n/10 .mu.m or more, where n is a rated voltage expressed in volts.

19 more elements

Dependencies are inferred from the claim text.

Power inverter having series connection of semiconductor devices each having an inverse parallel connection of an insulated gate bipolar transistor and a diode

Life of this patent

Power inverter having series connection of semiconductor devices each having an inverse parallel connection of an insulated gate bipolar transistor and a diode

Life of this patent

Abstract

Claims22