System and method for power module for inverter for electric vehicle

Abstract

A power module includes a first substrate having an outer surface and an inner surface, the first substrate extending from a first longitudinal end toward a second longitudinal end; a power switching member, the power switching member comprising a semiconductor die, the power switching member being coupled to the inner surface of the first substrate; a second substrate having an outer surface and an inner surface, the power switching member coupled to the inner surface of the second substrate, the second substrate extending from a first longitudinal end toward a second longitudinal end, wherein the first longitudinal end of the first substrate is longitudinally offset from the first longitudinal end of the second substrate; a first conductive spacer coupled to an inner surface of the first substrate and coupled to the inner surface of the second substrate; and a flexible circuit, the flexible circuit being coupled to the power switching member.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of priority to U.S. non-provisional patent application No. 18 / 175,295 filed on February 27, 2023, which claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 377,486 filed on September 28, 2022, U.S. Provisional Patent Application No. 63 / 377,501 filed on September 28, 2022, U.S. Provisional Patent Application No. 63 / 377,512 filed on September 28, 2022, and U.S. Provisional Patent Application No. 63 / 378,601 filed on October 6, 2022, the entire contents of which are incorporated herein by reference. Technical Field

[0003] Various embodiments of the present disclosure generally relate to a power module for an inverter for an electric vehicle, and more particularly to a power module including a conductive spacer or a flexible circuit. Background Art

[0004] Inverters, such as those used to drive motors in electric vehicles, are responsible for, for example, converting high voltage direct current (HVDC) to alternating current (AC) to drive the motor. In an inverter, power modules may include devices that generate a lot of heat. The layout and design of the power modules affect the operation of the device and the thermal characteristics of the power modules. Improper device operation or overheating of the power modules can impair the operation of the inverter.

[0005] The present disclosure is directed to overcoming one or more of these aforementioned challenges. Summary of the invention

[0006] In some aspects, the technology described herein relates to a power module, comprising: a first substrate having an outer surface and an inner surface; a semiconductor grain coupled to the inner surface of the first substrate; a second substrate having an outer surface and an inner surface, the semiconductor grain coupled to the inner surface of the second substrate; and a first conductive spacer coupled to the inner surface of the first substrate and to the inner surface of the second substrate.

[0007] In some aspects, the technology described herein relates to a power module wherein the first substrate further includes an intermediate section between the inner surface and the outer surface, wherein the intermediate section comprises ceramic, and the outer surface and the inner surface of the first substrate comprise metal.

[0008] In some aspects, the technology described herein relates to a power module that further includes a first lead coupled to an inner surface of a second substrate.

[0009] In some aspects, the technology described herein relates to a power module in which a first conductive spacer is coupled to a first portion of an inner surface of a second substrate and a semiconductor die is coupled to a second portion of the inner surface of the second substrate, wherein the first portion and the second portion are not directly coupled to each other.

[0010] In some aspects, the technology described herein relates to a power module that further includes a second conductive spacer coupled to an inner surface of the second substrate and to an inner surface of the first substrate.

[0011] In some aspects, the technology described herein relates to a power module in which a first conductive spacer and a second conductive spacer are coplanar.

[0012] In some aspects, the technology described herein relates to a power module in which the ceramic includes silicon nitride.

[0013] In some aspects, the technology described herein relates to a power module wherein the second substrate further includes an intermediate layer between the inner surface and the outer surface, wherein the intermediate layer includes ceramic, and the outer surface and the inner surface of the second substrate include metal.

[0014] In some aspects, the technology described herein relates to a power module in which a source connection and a connection of a semiconductor die are coplanar.

[0015] In some aspects, the technology described herein relates to a power module in which a semiconductor die includes a drain, wherein the drain is coupled to an inner surface of a first substrate.

[0016] In some aspects, the technology described herein relates to a power module wherein a semiconductor die includes a source, wherein the source is coupled to an inner surface of a second substrate.

[0017] In some aspects, the technology described herein relates to an inverter that includes a power module.

[0018] In some aspects, the technology described herein relates to a vehicle that includes an inverter.

[0019] In some aspects, the technology described herein relates to a system comprising: an inverter configured to convert DC power from a battery into AC power to drive a motor, wherein the inverter comprises: a power module for an inverter for an electric vehicle, the power module comprising: a first substrate; a second substrate; and a conductive spacer connecting the first substrate to the second substrate.

[0020] In some aspects, the technology described herein relates to a system that further includes a battery configured to supply DC power to an inverter and a motor configured to receive AC power from the inverter to drive the motor.

[0021] In some aspects, the technology described herein relates to a system comprising: a power module, the power module being for an inverter, the power module comprising: a lower substrate, the lower substrate comprising an upper conductive layer; an upper substrate, the upper substrate comprising the lower conductive layer; and one or more conductive spacers, the one or more conductive spacers being between the lower substrate and the upper substrate, the one or more conductive spacers being configured to maintain a distance between the lower substrate and the upper substrate and to provide a conductive path from the lower conductive layer to the upper conductive layer.

[0022] In some aspects, the technology described herein relates to a system wherein: the lower conductive layer includes a first lower conductive region, a second lower conductive region, and a third lower conductive region, and the upper conductive layer includes a first upper conductive region and a second upper conductive region.

[0023] In some aspects, the technology described herein relates to a system wherein: the one or more conductive spacers include a first conductive spacer and a second conductive spacer, the first conductive spacer connecting a first lower conductive region to a first upper conductive region, and the second conductive spacer connecting a second lower conductive region to a second upper conductive region.

[0024] In some aspects, the technology described herein relates to a system wherein the power module further includes: a first power switch configured to selectively electrically connect the first upper conductive region to the second lower conductive region; and a second power switch configured to selectively electrically connect the third lower conductive region to the second upper conductive region.

[0025] In some aspects, the technology described herein relates to a system wherein the power module further includes: a first interconnect on the first lower conductive region, a second interconnect on the third lower conductive region, and a third interconnect on the third lower conductive region.

[0026] In some aspects, the technology described herein relates to a system wherein: a first power switch is configured to selectively electrically connect a first interconnect to a third interconnect via a first lower conductive region, a first conductive spacer, a first upper conductive region, the first power switch, and a second lower conductive region, and a second power switch is configured to selectively electrically connect a second interconnect to the third interconnect via a third lower conductive region, a second power switch, a second upper conductive region, a second conductive spacer, and a second lower conductive region.

[0027] In some aspects, the technology described herein relates to a power module, comprising: a first substrate; a second substrate; a semiconductor grain disposed between the first substrate and the second substrate, the semiconductor grain having a drain coupled to the first substrate and a source coupled to the second substrate; a first conductive spacer disposed between the first substrate and the second substrate, wherein a connector between the first conductive spacer and the first substrate and a connector between the drain of the semiconductor grain and the first substrate are coplanar.

[0028] In some aspects, the technology described herein relates to a power module in which a connection between a first conductive spacer and a second substrate and a connection between a source of a semiconductor die and the second substrate are coplanar.

[0029] In some aspects, the technology described herein relates to a power module, comprising: a first substrate having an outer surface and an inner surface; a semiconductor die coupled to the inner surface of the first substrate; a second substrate having an outer surface and an inner surface, the semiconductor die coupled to the inner surface of the second substrate; and a flexible circuit coupled to the semiconductor die.

[0030] In some aspects, the technology described herein relates to a power module in which a flexible circuit is coupled to an inner surface of a second substrate.

[0031] In some aspects, the technology described herein relates to a power module wherein the flexible circuit includes an insulating material and a conductive material, wherein an inner surface of the second substrate is electrically insulated from the conductive material of the flexible circuit.

[0032] In some aspects, the technology described herein relates to a power module in which a conductive material of a flex circuit is coupled to a semiconductor die.

[0033] In some aspects, the technology described herein relates to a power module wherein a semiconductor die includes a gate, wherein a conductive material of a flex circuit is coupled to the gate of the semiconductor die.

[0034] In some aspects, the technology described herein relates to a power module in which a semiconductor die is coupled to a second substrate via a flex circuit.

[0035] In some aspects, the technology described herein relates to a power module wherein a semiconductor die includes a source connection, wherein the source connection is coupled to a second substrate via a flex circuit.

[0036] In some aspects, the technology described herein relates to a power module in which a semiconductor die includes a gate, wherein electrical connections to the gate are contained solely within a flexible circuit.

[0037] In some aspects, the technology described herein relates to a power module in which the semiconductor die includes a gate, wherein electrical connections to the gate within the power module are contained solely within a flexible circuit.

[0038] In some aspects, the technology described herein relates to a power module in which the semiconductor die includes a gate, wherein electrical connections within the power module to the gate do not extend through any portion of a second substrate.

[0039] In some aspects, the technology described herein relates to a power module wherein the first substrate further includes an intermediate section between the inner surface and the outer surface, wherein the intermediate section comprises ceramic, and the outer surface and the inner surface of the first substrate comprise metal.

[0040] In some aspects, the technology described herein relates to a power module in which the ceramic includes silicon nitride.

[0041] In some aspects, the technology described herein relates to a power module that further includes a first lead coupled to an inner surface of a second substrate.

[0042] In some aspects, the technology described herein relates to a power module wherein the second substrate further includes an intermediate surface between the inner surface and the outer surface, wherein the inner surface comprises ceramic, and the outer and inner surfaces of the second substrate comprise metal.

[0043] In some aspects, the technology described herein relates to a power module in which a semiconductor die includes a drain, wherein the drain is coupled to an inner surface of a first substrate.

[0044] In some aspects, the technology described herein relates to a power module wherein a semiconductor die includes a source, wherein the source is coupled to an inner surface of a second substrate.

[0045] In some aspects, the technology described herein relates to an inverter that includes a power module.

[0046] In some aspects, the technology described herein relates to a vehicle that includes an inverter.

[0047] In some aspects, the technology described herein relates to a power module comprising: a semiconductor die having a source connection, a drain connection, and a gate; a substrate coupled to the source connection; and a flex circuit coupled to the gate, wherein electrical connections to the gate within the power module are contained solely within the flex circuit.

[0048] In some aspects, the technology described herein relates to a power module comprising: a semiconductor die having a source connection, a drain connection, and a gate; a substrate coupled to the source connection; and a flexible circuit coupled to the gate, wherein an electrical connection to the gate within the power module does not extend through any portion of the substrate.

[0049] In some aspects, the technology described herein relates to a system comprising: an inverter configured to convert DC power from a battery into AC power to drive a motor, wherein the inverter comprises: a power module comprising: a first substrate comprising a first conductive layer; a second substrate comprising a second conductive layer; a power switching element between the first substrate and the second substrate; and a flexible layer between the first substrate and the second substrate, the flexible layer being electrically connected to the power switching element.

[0050] In some aspects, the technology described herein relates to a system in which a first conductive layer and a second conductive layer are configured to direct high voltage power through a power switch, and a flexible layer is configured to direct a control signal to the power switch.

[0051] In some aspects, the technology described herein relates to a system in which the flexible layer includes a base polyimide material, an inner conductive layer, and a bed cover.

[0052] In some aspects, the technology described herein relates to a system in which a base polyimide material of a flexible layer is laminated to a first conductive layer.

[0053] In some aspects, the technology described herein relates to a system wherein: a power switch includes a power switch gate connector, and a base polyimide material and an internal conductive layer are routed between a first conductive layer and the power switch gate connector, such that the internal conductive layer is electrically connected to the power switch gate connector, and the internal conductive layer is electrically insulated from the first conductive layer by the base polyimide material.

[0054] In some aspects, the technology described herein relates to a system in which a flexible layer is configured to insulate a perimeter of a power switch from a first conductive layer.

[0055] In some aspects, the technology described herein relates to a system in which a flexible layer is configured to prevent interruption of current flowing in a first conductive layer.

[0056] In some aspects, the technology described herein relates to a system that further includes a battery configured to supply DC power to an inverter and a motor configured to receive AC power from the inverter to drive the motor.

[0057] In some aspects, the technology described herein relates to a system comprising: a power module, the power module being for an inverter, the power module comprising: a first substrate, the first substrate comprising a first conductive layer; a second substrate, the second substrate comprising a second conductive layer; a power switching element, the power switching element being between the first substrate and the second substrate; and a flexible layer, the flexible layer being between the first substrate and the second substrate, the flexible layer being electrically connected to the power switching element.

[0058] In some aspects, the technology described herein relates to a system, wherein: a power switch includes a power switch gate connector, and the power module further includes: a point of use controller between a first substrate and a second substrate, the point of use controller being configured to provide a signal to the power switch gate connector via a flexible layer to control the power switch.

[0059] In some aspects, the technology described herein relates to a system wherein: the power switch further includes a control connection, and the point-of-use controller is electrically connected to the control connection via the flexible layer.

[0060] In some aspects, the technology described herein relates to a system wherein: the power switch further includes: a first power connector connected to one or more of the first conductive layer or the second conductive layer, and a second power connector connected to one or more of the first conductive layer or the second conductive layer.

[0061] In some aspects, the technology described herein relates to a system in which a first power connection is configured to connect to a power source and a second power connection is configured to connect to a load.

[0062] In some aspects, the technology described herein relates to a system wherein: a power switch is configured to control current between a first conductive layer and a second conductive layer to control current between a power source and a load, and a flexible layer is configured to direct a control signal to the power switch.

[0063] In some aspects, the technology described herein relates to a system comprising: a power module, the power module being for an inverter, the power module comprising: a lower substrate, the lower substrate comprising a lower conductive layer; an upper substrate, the upper substrate comprising an upper conductive layer; a power switch, the power switch being between the lower conductive layer and the upper conductive layer, the power switch comprising a power switch gate connector; and a flexible layer, the flexible layer being between the lower conductive layer and the upper conductive layer, the flexible layer being electrically connected to the power switch gate connector.

[0064] In some aspects, the technology described herein relates to a system wherein the power module further comprises: a gate control pin, wherein the flexible layer electrically connects the gate control pin to the power switch gate connector.

[0065] In some aspects, the technology described herein relates to a system wherein the power module further comprises: a gate control pin and a point of use controller, wherein the flexible layer electrically connects the gate control pin to the point of use controller and electrically connects the point of use controller to the power switch gate connection.

[0066] In some aspects, the technology described herein relates to a system in which the flexible layer includes an insulating layer and a conductive layer.

[0067] In some aspects, the technology described herein relates to a system in which an insulating layer is connected to an underlying conductive layer.

[0068] In some aspects, the technology described herein relates to a system wherein the power switch comprises a die, and wherein the die comprises an upper surface connected to an upper conductive layer and a lower surface connected to a lower conductive layer through an opening in a flexible layer.

[0069] In some aspects, the technology described herein relates to a power module, comprising: a first substrate having an outer surface and an inner surface, the first substrate extending from a first longitudinal end toward a second longitudinal end; a semiconductor die coupled to the inner surface of the first substrate; and a second substrate having an outer surface and an inner surface, the semiconductor die coupled to the inner surface of the second substrate, the second substrate extending from the first longitudinal end toward the second longitudinal end, wherein the first longitudinal end of the first substrate is longitudinally offset from the first longitudinal end of the second substrate.

[0070] In some aspects, the technology described herein relates to a power module in which a second longitudinal end of a first substrate is offset from a second longitudinal end of a second substrate.

[0071] In some aspects, the technology described herein relates to a power module in which a length of a first substrate is approximately equal to a length of a second substrate.

[0072] In some aspects, the technology described herein relates to a power module in which a length of a first substrate is greater than a length of a second substrate.

[0073] In some aspects, the technology described herein relates to a power module that further includes a first leadframe coupled to an inner surface of the first substrate.

[0074] In some aspects, the technology described herein relates to a power module that further includes a second leadframe coupled to an inner surface of the first substrate.

[0075] In some aspects, the technology described herein relates to a power module that further includes a second leadframe coupled to an inner surface of the second substrate.

[0076] In some aspects, the technology described herein relates to a power module wherein the first leadframe has a thickness greater than 500 microns.

[0077] In some aspects, the technology described herein relates to a power module wherein the first leadframe has a thickness greater than 700 microns.

[0078] In some aspects, the technology described herein relates to a power module in which a first lead frame has a thickness greater than a space between an inner surface of a first substrate and an inner surface of a second substrate.

[0079] In some aspects, the technology described herein relates to a power module further comprising an overmold coupled to the first substrate, the second substrate, and the semiconductor die.

[0080] In some aspects, the technology described herein relates to an inverter that includes a power module.

[0081] In some aspects, the technology described herein relates to a vehicle that includes an inverter.

[0082] In some aspects, the technology described herein relates to a power module, comprising: a first substrate having an outer surface and an inner surface, the first substrate extending from a first longitudinal end toward a second longitudinal end; a semiconductor die coupled to the inner surface of the first substrate; a second substrate having an outer surface and an inner surface, the semiconductor die coupled to the inner surface of the second substrate, the second substrate extending from the first longitudinal end toward the second longitudinal end; and a lead frame coupled to the inner surface of the first substrate, wherein a thickness of the lead frame is greater than a distance from the inner surface of the first substrate to the inner surface of the second substrate.

[0083] In some aspects, the technology described herein relates to a system comprising: an inverter configured to convert DC power from a battery into AC power to drive a motor, wherein the inverter comprises: a power module comprising: a lower substrate comprising a lower conductive layer extending in a lower plane; and an upper substrate comprising an upper conductive layer extending in an upper plane separated from the lower plane, wherein an end of the upper substrate is offset from a corresponding end of the lower substrate in the upper plane so that a normal vector from the upper plane at the end of the upper substrate does not intersect the lower substrate.

[0084] In some aspects, the technology described herein relates to a system further comprising: a first lead frame connected to a lower conductive layer, wherein at least a portion of the first lead frame is in an upper plane; and a second lead frame connected to the upper conductive layer, wherein at least a portion of the second lead frame is in a lower plane.

[0085] In some aspects, the technology described herein relates to a system wherein one or more of the first leadframe or the second leadframe has a thickness greater than 500 microns.

[0086] In some aspects, the technology described herein relates to a system wherein a distance between an inner surface of an upper substrate and an inner surface of a lower substrate is less than 500 microns.

[0087] In some aspects, the technology described herein relates to a system in which the length of the lower substrate is approximately equal to the length of the upper substrate.

[0088] In some aspects, the technology described herein relates to a system that further includes a battery configured to supply DC power to an inverter and a motor configured to receive AC power from the inverter to drive the motor.

[0089] In some aspects, the technology described herein relates to a system comprising: a power module, the power module being for an inverter, the power module comprising: a first substrate, the first substrate comprising a first conductive layer extending in a first plane; and a second substrate, the second substrate comprising a second conductive layer extending in a second plane separated from the first plane, wherein an end of the first substrate is offset from a corresponding end of the second substrate in the first plane so that a normal vector from the first plane at the end of the first substrate does not intersect the second substrate.

[0090] In some aspects, the technology described herein relates to a system comprising: a power module, the power module being for an inverter, the power module comprising: a lower substrate, the lower substrate comprising a lower conductive layer extending in a lower plane; and an upper substrate, the upper substrate comprising an upper conductive layer extending in an upper plane separated from the lower plane; a first lead frame, the first lead frame connected to the lower conductive layer, wherein at least a portion of the first lead frame is in the upper plane; and a second lead frame, the second lead frame connected to the upper conductive layer, wherein at least a portion of the second lead frame is in the lower plane.

[0091] In some aspects, the technology described herein relates to a system comprising: an inverter configured to convert DC power from a battery into AC power to drive a motor, wherein the inverter comprises: a first power module comprising: a first substrate comprising a first conductive layer; a second substrate comprising a second conductive layer; a power switch between the first conductive layer and the second conductive layer, the power switch comprising a gate connector, wherein the power switch is configured to selectively electrically connect the first conductive layer to the second conductive layer based on a signal to the gate connector; and a point-of-use controller between the first conductive layer and the second conductive layer, the point-of-use controller being configured to provide a signal to the gate connector to control the power switch.

[0092] In some aspects, the technology described herein relates to a system wherein the first power module further comprises: a first lead frame connection; and a second lead frame connection, wherein a point of use controller is on the first substrate and between the first lead frame connection and the second lead frame connection.

[0093] In some aspects, the technology described herein relates to a system, wherein the first power module further comprises: a conductive spacer between the first substrate and the second substrate, wherein the first leadframe connection is connected to the first power switch via the conductive spacer.

[0094] In some aspects, the technology described herein relates to a system wherein the first power module further comprises: a flexible layer between the first substrate and the second substrate, wherein the point of use controller is connected to the gate connection via the flexible layer.

[0095] In some aspects, the technology described herein relates to a system wherein the first power module further comprises: a control connection, wherein the first point-of-use controller is connected to the control connection via the flexible layer.

[0096] In some aspects, the technology described herein relates to a system in which a power switching element includes one or more silicon carbide grains.

[0097] In some aspects, the technology described herein relates to a system wherein the inverter further comprises: a second power module; and a third power module.

[0098] In some aspects, the technology described herein relates to a system that further includes a battery configured to supply DC power to an inverter and a motor configured to receive AC power from the inverter to drive the motor.

[0099] In some aspects, the technology described herein relates to a system comprising: a power module, the power module being for an inverter, the power module comprising: a first substrate, the first substrate comprising a first conduction region and a second conduction region; a second substrate, the second substrate comprising a third conduction region and a fourth conduction region; a first power switch, the first power switch being between the first substrate and the second substrate, the first power switch comprising a first gate connector, wherein the first power switch is configured to selectively electrically connect the first conduction region to the third conduction region based on a first signal to the first gate connector; and a first point-of-use controller, the first point-of-use controller being between the first substrate and the second substrate, the first point-of-use controller being configured to provide a first signal to the first gate connector to control the first power switch.

[0100] In some aspects, the technology described herein relates to a system, wherein the power module further includes: a second power switch element between the first substrate and the second substrate, the second power switch element including a second gate connector, wherein the second power switch element is configured to selectively electrically connect the second conductive region to the fourth conductive region based on a second signal to the second gate connector.

[0101] In some aspects, the technology described herein relates to a system wherein the power module further comprises: a second point-of-use controller between the first substrate and the second substrate, the second point-of-use controller configured to provide a second signal to the second gate connector to control the second power switch.

[0102] In some aspects, the technology described herein relates to a system wherein the power module further comprises: a first lead frame connection; and a second lead frame connection, wherein a first point of use controller is on the first substrate and between the first lead frame connection and the second lead frame connection.

[0103] In some aspects, the technology described herein relates to a system, wherein the power module further comprises: a conductive spacer between the first substrate and the second substrate, wherein the first leadframe connection is connected to the first power switch via the conductive spacer.

[0104] In some aspects, the technology described herein relates to a system wherein the power module further comprises: a flexible layer between the first substrate and the second substrate, wherein the first point of use controller is connected to the first gate connection via the flexible layer.

[0105] In some aspects, the technology described herein relates to a system, the system comprising: a power module, the power module for an inverter, the power module comprising: a lower substrate, the lower substrate comprising a lower conductive layer, the lower conductive layer comprising a first lower conductive region and a second lower conductive region; an upper substrate, the upper substrate comprising an upper conductive layer, the upper conductive layer comprising a first upper conductive region and a second upper conductive region; a first power switch, the first power switch between the first lower conductive region and the first upper conductive region, the first power switch comprising a first gate connector, wherein the first power switch is configured to selectively electrically connect the first lower conductive region to the first upper conductive region based on a first signal to the first gate connector; a first use A point controller, the first point-of-use controller is between the lower conductive layer and the upper conductive layer, the first point-of-use controller is configured to provide a first signal to the first gate connector to control the first power switch; a second power switch, the second power switch is between the second lower conductive region and the second upper conductive region, the second power switch includes a second gate connector, wherein the second power switch is configured to selectively electrically connect the second lower conductive region to the second upper conductive region based on a second signal to the second gate connector; a second point-of-use controller, the second point-of-use controller is between the lower conductive layer and the upper conductive layer, the second point-of-use controller is configured to provide a second signal to the second gate connector to control the second power switch.

[0106] In some aspects, the technology described herein relates to a system wherein the power module further comprises: a first lead frame connection; and a second lead frame connection, wherein a first point of use controller is on a lower substrate and between the first lead frame connection and the second lead frame connection.

[0107] In some aspects, the technology described herein relates to a system wherein the power module further comprises: a third lead frame connection, wherein a second point of use controller is on the lower substrate and between the third lead frame connection and the second lead frame connection.

[0108] In some aspects, the technology described herein relates to a system wherein the power module further comprises: a conductive spacer between the lower substrate and the upper substrate, wherein the first leadframe connection is connected to the first power switch via the conductive spacer.

[0109] In some aspects, the technology described herein relates to a system wherein the power module further comprises: a flexible layer between the lower conductive layer and the upper conductive layer, wherein the first point of use controller is connected to the first gate connection via the flexible layer.

[0110] In some aspects, the technology described herein relates to a system wherein the power module further comprises: a control connection, wherein the first point-of-use controller is connected to the control connection via the flexible layer.

[0111] In some aspects, the technology described herein relates to a power module, comprising: a first substrate having an outer surface and an inner surface, the first substrate extending from a first longitudinal end toward a second longitudinal end; a power switching element comprising a semiconductor grain, the power switching element coupled to the inner surface of the first substrate; a second substrate having an outer surface and an inner surface, the power switching element coupled to the inner surface of the second substrate, the second substrate extending from the first longitudinal end toward the second longitudinal end, wherein the first longitudinal end of the first substrate is longitudinally offset from the first longitudinal end of the second substrate; a first conductive spacer coupled to the inner surface of the first substrate and the inner surface of the second substrate; and a flexible circuit coupled to the power switching element.

[0112] In some aspects, the technology described herein relates to a power module wherein the first substrate further includes an intermediate layer between the inner surface and the outer surface, wherein the intermediate layer includes ceramic, and the outer surface and the inner surface of the first substrate include metal.

[0113] In some aspects, the technology described herein relates to a power module wherein a conductive spacer is coupled to a first portion of an inner surface of a second substrate and a power switch is coupled to a second portion of the inner surface of the second substrate, wherein the first portion and the second portion are not directly coupled to each other.

[0114] In some aspects, the technology described herein relates to a power module that further includes a second conductive spacer coupled to an inner surface of the second substrate and to an inner surface of the first substrate.

[0115] In some aspects, the technology described herein relates to a power module in which the semiconductor die includes silicon carbide.

[0116] In some aspects, the technology described herein relates to a power module wherein the second substrate further includes an intermediate layer between the inner surface and the outer surface, wherein the intermediate layer includes ceramic, and the outer surface and the inner surface of the second substrate include metal.

[0117] In some aspects, the technology described herein relates to a power module in which a source connection of a power switch is coplanar with a connection.

[0118] In some aspects, the technology described herein relates to a power module, wherein a power switch includes a drain, wherein the drain is coupled to an inner surface of a first substrate.

[0119] In some aspects, the technology described herein relates to a power module, wherein the power switch includes a drain, wherein the drain is coupled to an inner surface of a second substrate.

[0120] In some aspects, the technology described herein relates to a power module wherein the flexible circuit includes an insulating material and a conductive material, wherein an inner surface of the second substrate is electrically insulated from the conductive material of the flexible circuit.

[0121] In some aspects, the technology described herein relates to a power module in which a power switch includes a gate, wherein electrical connections to the gate are contained solely within a flexible circuit.

[0122] In some aspects, the technology described herein relates to a power module in which a power switch includes a gate, wherein electrical connections within the power module to the gate are contained solely within a flexible circuit.

[0123] In some aspects, the technology described herein relates to a power module wherein the power switch includes a gate, wherein electrical connections within the power module to the gate do not extend through any portion of the second substrate.

[0124] In some aspects, the technology described herein relates to a power module, which further includes: a first connector; a second connector, wherein the power switch includes a first gate terminal, and the power switch is configured to control a first current between the first connector and the second connector based on a first signal to the first gate terminal; and a first point-of-use controller, which is configured to provide a first signal to the first gate terminal to control the first power switch.

[0125] In some aspects, the technology described herein relates to an inverter that includes a power module.

[0126] In some aspects, the technology described herein relates to a vehicle that includes an inverter.

[0127] In some aspects, the technology described herein relates to a power module, the power module comprising: a first substrate having an outer surface and an inner surface, the first substrate extending from a first longitudinal end toward a second longitudinal end; a power switch, the power switch comprising a semiconductor grain coupled to the inner surface of the first substrate, wherein the semiconductor grain comprises silicon carbide; a second substrate having an outer surface and an inner surface, the semiconductor grain coupled to the inner surface of the second substrate, the second substrate extending from the first longitudinal end toward the second longitudinal end, wherein the first longitudinal end of the first substrate is longitudinally offset from the first longitudinal end of the second substrate; a first conductive spacer, the first conductive spacer connected to the inner surface of the first substrate and coupled to the inner surface of the second substrate; a flexible circuit coupled to the semiconductor grain; a first connector; a second connector, wherein the power switch comprises a first gate terminal, the first power switch is configured to control a first current between the first connector and the second connector based on a first signal to the first gate terminal; and a first point-of-use controller, the first point-of-use controller is configured to provide a first signal to the first gate terminal to control the first power switch.

[0128] In some aspects, the technology described herein relates to an inverter that includes a power module.

[0129] In some aspects, the technology described herein relates to a vehicle that includes an inverter.

[0130] In some aspects, the technology described herein relates to a power module, the power module comprising: a first substrate, the first substrate having an outer surface and an inner surface, the first substrate extending from a first longitudinal end toward a second longitudinal end; a power switching element, the power switching element comprising a semiconductor grain coupled to the inner surface of the first substrate, wherein the semiconductor grain comprises silicon carbide; a second substrate, the second substrate having an outer surface and an inner surface, the semiconductor grain coupled to the inner surface of the second substrate, the second substrate extending from the first longitudinal end toward the second longitudinal end, wherein the first longitudinal end of the first substrate is longitudinally offset from the first longitudinal end of the second substrate; a first conductive spacer a spacer, the first conductive spacer being connected to the inner surface of the first substrate and coupled to the inner surface of the second substrate; a flexible circuit, the flexible circuit being coupled to the semiconductor die; a first connector; a second connector, wherein the power switch includes a first gate terminal, the first power switch is configured to control a first current between the first connector and the second connector based on a first signal to the first gate terminal, wherein the electrical connection to the first gate terminal within the power module does not extend through any portion of the second substrate; and a first point-of-use controller, the first point-of-use controller being configured to provide a first signal to the first gate terminal to control the first power switch.

[0131] Other objects and advantages of the disclosed embodiments will be described in part in the following description, and in part will be obvious from the description, or can be understood by practicing the disclosed embodiments. The objects and advantages of the disclosed embodiments will be realized and achieved by means of the elements and combinations particularly pointed out in the appended claims.

[0132] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosed embodiments, as claimed. BRIEF DESCRIPTION OF THE DRAWINGS

[0133] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate various exemplary embodiments and, together with the description, serve to explain the principles of the disclosed embodiments.

[0134] Figure 1 An exemplary system infrastructure for a vehicle including a combined inverter and converter is depicted according to one or more embodiments.

[0135] Figure 2 Depicted is a method for providing a point-of-use switching controller according to one or more embodiments. Figure 1 An exemplary system infrastructure of a combined inverter and converter.

[0136] Figure 3 Describes a method for Figure 2 An exemplary system infrastructure for a controller of FIG.

[0137] Figure 4 Describes a method for Figure 2 An exemplary system infrastructure for a point-of-use switching controller.

[0138] Figure 5 Describes a method for Figure 4 An exemplary system infrastructure of an upper power module.

[0139] Figure 6 Depicted is an exemplary electrical schematic for a power module including a conductive spacer according to one or more embodiments.

[0140] Figure 7 Depicted is an exemplary architecture for a power module including a conductive spacer according to one or more embodiments.

[0141] Figure 8 Depicted are cross-sectional views of exemplary architectures for a power module including conductive spacers in accordance with one or more embodiments.

[0142] Fig. 9Depicted in cross-section is a single-sided cooling heat flow of an exemplary architecture for a power module including a conductive spacer in accordance with one or more embodiments.

[0143] Fig.10 Depicted are components of a power module having devices on two substrates and components of an exemplary power module having devices on a single substrate in accordance with one or more embodiments.

[0144] Fig.11 Depicted are components of an exemplary power module including a substrate layer and a flex layer according to one or more embodiments.

[0145] Fig.12 Depicted are cross-sectional views of exemplary architectures for a power module including surface mount components in accordance with one or more embodiments.

[0146] Fig.13 Depicted are cross-sectional views of exemplary architectures for a power module including a shifted substrate in accordance with one or more embodiments.

[0147] Fig.14 Depicted are components of an exemplary power module including a displaced substrate according to one or more embodiments.

[0148] Fig.15 Depicted is a cross-sectional view of an exemplary architecture for a sintered power module including a shifted substrate, according to one or more embodiments.

[0149] Fig.16A and Fig. 16B Depicted are components of an exemplary sintered power module including a displaced substrate according to one or more embodiments.

[0150] Fig.17 Depicted is a cross-sectional view of an exemplary architecture for a power module including a point-of-use switching controller in accordance with one or more embodiments.

[0151] Fig.18 Depicted are components of an exemplary power module including a point-of-use switching controller according to one or more embodiments. DETAILED DESCRIPTION

[0152] Both the foregoing general description and the following detailed description are exemplary and explanatory only and do not constrain the claimed features. As used herein, the terms "comprises," "comprising," "has," "having," "includes," "including," or other variations thereof are intended to encompass non-exclusive inclusions such that a process, method, article, or device that includes a series of elements includes not only those elements, but may also include other elements that are not explicitly listed or inherent to such process, method, article, or device. In the present disclosure, unless otherwise stated, relative terms (such as, for example, "about," "substantially," and "approximately") are used to indicate possible ±10% variations in the stated values. In the present disclosure, unless otherwise stated, any numerical value may include possible ±10% variations in the stated values.

[0153] The terms used below may be interpreted in their broadest reasonable manner, although they are being used in conjunction with a detailed description of certain specific examples of the present disclosure. Indeed, certain terms may even be emphasized below; however, any term intended to be interpreted in any constrained manner will be explicitly and specifically defined as such in this detailed description. For example, in the context of the present disclosure, a switching device may be described as a switching element or device, but may refer to any device for controlling power flow in a circuit. For example, a switching element may be, for example, a metal oxide semiconductor field effect transistor (MOSFET), a bipolar junction transistor (BJT), an insulated gate bipolar transistor (IGBT) or a relay, or any combination thereof, but is not limited thereto.

[0154] Various embodiments of the present disclosure relate generally to systems and methods for an adaptive driver for an inverter for an electric vehicle, and more particularly to systems and methods for an adaptive driver for a power device switch of an inverter for an electric vehicle.

[0155] Inverters (such as those used to drive motors in electric vehicles) are responsible for converting high voltage direct current (HVDC) into alternating current (AC) to drive the motor. A three-phase inverter may include a bridge having six power device switches (e.g., power transistors such as IGBTs or MOSFETs) that are controlled by pulse width modulation (PWM) signals generated by a controller. The inverter may include three half-H-bridge switches to control phase voltages, upper and lower gate drivers to control the switches, a PWM controller, and glue logic between the PWM controller and the gate driver. The PWM controller may generate signals to define the expected state of the system. The gate driver may send signals from the PWM controller to the half-H-bridge switches. The half-H-bridge switches may drive the phase voltages. The inverter may include an isolation barrier between a low voltage plane and a high voltage plane. The signal may be passed from the PWM controller to the half-H-bridge switch by passing through the isolation barrier, which may employ optical, converter-based, or capacitor-based isolation. The PWM signal may be distorted when passing through the glue logic, which may include resistive, capacitive, or other types of filtering. Due to the electrical isolation barrier and other delays within the gate driver, the PWM signal may be distorted when passing through the gate driver. The PWM signal may be distorted when the signal is processed by the half-H switching element via the gate driver output.

[0156] Gate drivers withstand common-mode transients that occur during field effect transistor (FET) switching and when one side of a floating high voltage terminal is shorted to ground or subjected to electrostatic discharge. These voltage transients can cause fast edges that can form common-mode current bursts through electrical isolation. Gate drivers may need to demonstrate common-mode transient immunity (CMTI) in order to be effective and safe.

[0157] The gate driver may have a high voltage domain in common with the voltage plane of the associated FET. Further, the high voltage plane may be supplied by a flyback converter, which may be isolated from the low voltage plane by a transformer. The high voltage domain power supply may be used to provide power to such a circuit that sources and sinks gate current to drive the FET and can detect FET faults, thereby acting on the faults and / or transmitting the faults to the low voltage domain. The gate driver may include an electrical channel dedicated to FET commands, and one or more bidirectional or unidirectional electrical channels dedicated to FET communications.

[0158] High current switching transients can form strong electromagnetic (EM) fields that can couple into nearby metal traces. The magnitude and frequency of the coupled current can depend on the layout of the FET packaging solution and the direction and length of the metal traces between the FET and the control integrated circuit (IC). For example, a typical value for the coupled current can be up to 1A at an AC frequency of up to 100MHz. Typically, within the circuit, the gate driver IC can be placed far enough away from the FET so that the high EM field is not directly coupled into the internal metal traces within the gate driver IC. The gate driver is placed at a distance from the EM field so that the induced current within the circuit is below the level that will cause the gate driver to malfunction, or a metal shield is placed between the gate driver and the source of the EM field to protect the gate driver circuit. The output terminals of the gate driver connected to the FET are exposed to the EM field at a point where the output terminals are no longer covered by the shield. The gate driver switches large currents (e.g., such as 5A to 15A) through these exposed terminals. The large currents switched are usually larger in magnitude than the EM induced current. The gate driver can overdrive the induced current to maintain control of the FET. The gate driver and the high side of the FET may share a common ground and gate control signal trace, both of which may be susceptible to coupled currents.

[0159] The gate driver can turn on low resistance switches to source and sink gate current. Sometimes a series resistor can be added to limit the gate current. The switched gate current can be greater than the coupling current in order to maintain control of their respective FETs.

[0160] The gate driver may be able to sense the FET operating voltage or current in order to provide feedback and react to faults. An overcurrent fault may typically be detected by sensing the FET drain to source voltage and comparing the sensed voltage to a reference value. The sensed voltage may be heavily filtered to reject coupled currents. Filtering may slow the response to a fault condition, causing a delay in response. For example, the rate of current increase due to a low resistance short may reach damaging levels before being detected by a heavily filtered drain to source voltage detection strategy. The resulting short may damage the FET or the vehicle before being detected and cut off.

[0161] According to one or more embodiments, a FET driver circuit may provide fast overcurrent detection by shunt current sensing, or by diverting a portion of the load current through a parallel FET that may have a current sensing circuit. Utilizing either strategy may require a "point of use IC" in which the sensing circuit is very close to the FET. Even if the point of use IC and the remote controller are resistant to EM fields, the communication between the point of use IC and the remote controller is still susceptible to induced currents. Point of use ICs have been implemented in low EM field applications, such as smart FETs for automotive applications. However, point of use ICs have not yet been used in high EM field applications. High EM fields can be fields that (i) induce a current within the IC that exceeds the operating current of the IC and causes a malfunction, or (ii) induce a differential voltage within the IC that exceeds the operating differential voltage and causes a malfunction. High EM fields can be, for example, fields greater than about 10A or about 100V.

[0162] The choice of a half-bridge topology for a power module can operate with lower loop inductance, less ringing and voltage overshoot than other topologies. The use of silicon carbide metal oxide semiconductor field effect transistors (SiC MOSFETs) results in shortened switching times relative to, for example, some silicon insulated gate bipolar transistors (Si IGBTs), and the reduced inductance of the half-bridge module can be sought to fully exploit this capability.

[0163] Half-bridge circuits can be used in power electronics to apply a pulse width modulated voltage to control the current applied to an inductive load such as a motor. In such circuits, the source and its associated circuitry can most naturally be on opposite substrates for the two switches in the half-bridge. That is, in a half-bridge circuit, the source of the upper switch and the drain of the lower switch can share a common connection with the load, and the source and drain can be on opposite sides of the bare die used in power applications. For high voltage double-sided cooling applications, the source and drain can be cooled at their interconnects through an insulating substrate, with the drain on one substrate and the source on the other.

[0164] Each power device in the bridge may have circuitry that references the source connection. However, having the sources on opposing substrates in a double-sided cooled package may make assembly difficult. For example, bottom-up assembly for a double-sided cooled module may be compromised because each substrate and its source reference circuitry must be assembled independently and then assembled together. Furthermore, the die associated with the lower portion will be reversed from those of the upper portion, but the source and drain interconnects may have different voltage isolation requirements, causing differences at the interconnects, which may cause coplanarity issues during assembly.

[0165] Such difficulties during assembly may result in lower yields and higher costs. Additionally, some devices may face efficiency issues related to the paths for heat and electrical current.

[0166] Figure 1 An exemplary system infrastructure for a vehicle including a combined inverter and converter according to one or more embodiments is depicted. In the context of the present disclosure, the combined inverter and converter may be referred to as an inverter. Figure 1 As shown, the electric vehicle 100 may include an inverter 110, a motor 190, and a battery 195. The inverter 110 may include a component for receiving electric power from an external source and outputting electric power to charge the battery 195 of the electric vehicle 100. For example, the inverter 110 may convert DC power from the battery 195 in the electric vehicle 100 into AC power to drive the motor 190 of the electric vehicle 100, but the embodiment is not limited thereto. For example, the inverter 110 may be bidirectional and may convert DC power into AC power, or convert AC power into DC power, such as during regenerative braking. The inverter 110 may be a three-phase inverter, a single-phase inverter, or a multi-phase inverter.

[0167] Figure 2 Depicted is a method for providing a point-of-use switching controller according to one or more embodiments. Figure 1 The electric vehicle 100 may include an inverter 110, a motor 190, and a battery 195. The inverter 110 may include an inverter controller 300 ( Figure 314). The inverter 110 may include a low voltage upper phase controller 120 separated from a high voltage upper phase controller 130 by an electrical isolator 150, and an upper phase power module 140. The upper phase power module 140 may include a point-of-use upper phase controller 142 and an upper phase switch 144. The inverter 110 may include a low voltage lower phase controller 125 separated from a high voltage lower phase controller 135 by an electrical isolator 150, and a lower phase power module 145. The lower phase power module 145 may include a point-of-use lower phase controller 146 and a lower phase switch 148. The upper phase switch 144 and the lower phase switch 148 may be connected to a motor 190 and a battery 195. The electrical isolator 150 may be one or more of optical, converter-based, or capacitor-based isolation. For example, the electrical isolator 150 may be one or more capacitors having a value from about 20 fF to about 100 fF, having a breakdown voltage from about 6 kV to about 12 kV. The electrical isolator 150 may include a pair of capacitors, wherein one capacitor in the pair carries a complementary data signal from the other capacitor in the pair to form a differential signal that is rejected for common mode noise. The electrical isolator 150 may include more than one capacitor in series. The electrical isolator 150 may include one capacitor located on a first IC, or may include a first capacitor located on a first IC and a second capacitor located on a second IC that communicates with the first IC.

[0168] The inverter 110 may include a low voltage region (e.g., where the voltage is typically less than 5V) and a high voltage region (e.g., where the voltage may exceed 500V). The low voltage region may be separated from the high voltage region by an electrical isolator 150. The inverter controller 300 may be in the low voltage region of the inverter 110, and may send a signal to and receive a signal from the low voltage upper phase controller 120. The low voltage upper phase controller 120 may be in the low voltage region of the inverter 110, and may send a signal to and receive a signal from the high voltage upper phase controller 130. The low voltage upper phase controller 120 may send a signal to and receive a signal from the low voltage lower phase controller 125. The high voltage upper phase controller 130 may be in the high voltage region of the inverter 110. Therefore, the signal between the low voltage upper phase controller 120 and the high voltage upper phase controller 130 passes through the electrical isolator 150. The high voltage upper phase controller 130 may send signals to and receive signals from a point-of-use upper phase controller 142 in the upper phase power module 140. The point-of-use upper phase controller 142 may send signals to and receive signals from an upper phase switch 144. The upper phase switch 144 may be connected to a motor 190 and a battery 195. For example, the upper phase switch 144 and the lower phase switch 148 may be used to transfer energy from the motor 190 to the battery 195, from the battery 195 to the motor 190, from an external source to the battery 195, or from the battery 195 to an external source. The lower phase system of the inverter 110 may be similar to the upper phase system described above.

[0169] Figure 3 Describes a method for Figure 2 FIG. 3 is an exemplary system infrastructure of an inverter controller 300 . The inverter controller 300 may include one or more controllers.

[0170] The inverter controller 300 may include a set of instructions that can be executed to cause the inverter controller 300 to perform any one or more of the methods or computer-based functions disclosed herein. The inverter controller 300 may operate as a standalone device, or may be connected to other computer systems or peripheral devices, for example using a network.

[0171] In a networked deployment, the inverter controller 300 can operate in the capacity of a server, or as a client in a server-client user network environment, or as a peer computer system in a peer (or distributed) network environment. The inverter controller 300 can also be implemented as or incorporated into various devices, such as a DC to DC converter, an AC to DC converter, a charger, a DC to AC converter for controlling a motor and providing AC power, a personal computer (PC), a mobile device, a laptop computer, a desktop computer, a communication device, a control system, a network device, a network router, a switch or a bridge, or any other machine capable of executing a set of instructions (sequentially or otherwise) (the set of instructions specifies the actions to be taken by the machine). In a specific implementation, the inverter controller 300 can be implemented using an electronic device that provides voice, video or data communication. Further, although the inverter controller 300 is illustrated as a single system, the term "system" should also be understood to include any collection of systems or subsystems that execute one or more sets of instructions individually or jointly to perform one or more computer functions.

[0172] like Figure 3 As shown, the inverter controller 300 may include a processor 302, such as a central processing unit (CPU), a graphics processing unit (GPU), or both. The processor 302 may be a component in a variety of systems. For example, the processor 302 may be part of a standard inverter. The processor 302 may be one or more general-purpose processors, digital signal processors, application-specific integrated circuits, field programmable gate arrays, servers, networks, digital circuits, analog circuits, combinations thereof, or other devices now known or later developed for analyzing and processing data. The processor 302 may implement a software program, such as a manually (i.e., programmed) automatically generated code.

[0173] The inverter controller 300 may include a memory 304 that can communicate via a bus 308. The memory 304 may be a main memory, a static memory, or a dynamic memory. The memory 304 may include, but is not limited to, computer-readable storage media, such as various types of volatile and non-volatile storage media, including but not limited to random access memory, read-only memory, programmable read-only memory, electrically programmable read-only memory, electrically erasable read-only memory, flash memory, tape or disk, optical media, etc. In one specific implementation, the memory 304 includes a cache or random access memory for the processor 302. In an alternative specific implementation, the memory 304 is separated from the processor 302, such as a cache memory, system memory, or other memory of the processor. The memory 304 may be an external storage device or database for storing data. Examples include a hard drive, a compact disk ("CD"), a digital video disk ("DVD"), a memory card, a memory stick, a floppy disk, a universal serial bus ("USB") storage device, or any other device operable to store data. The memory 304 is operable to store instructions that can be executed by the processor 302. The functions, actions, or tasks illustrated in the figures or described herein may be performed by the processor 302 executing instructions stored in the memory 304. The functions, actions, or tasks are not related to a particular type of instruction set, storage medium, processor, or processing strategy, and may be performed by software, hardware, integrated circuits, firmware, microcode, etc. operating alone or in combination. Likewise, processing strategies may include multi-processing, multi-tasking, parallel processing, etc.

[0174] As shown, the inverter controller 300 may further include a display 310 and / or interface with the display, such as a liquid crystal display (LCD), an organic light emitting diode (OLED), a flat panel display, a solid state display, a cathode ray tube (CRT), a projector, a printer, or other display devices now known or later developed for outputting the determined information. For example, the display 310 may serve as an interface for a user to view the operation of the processor 302, or specifically serve as an interface with software stored in the memory 304 or in the drive unit 306, such as for programming.

[0175] Additionally or alternatively, for example, the inverter controller 300 may include an input device 312 configured to allow a user to interact with any of the components of the inverter controller 300, such as for calibration or testing. The input device 312 may be a numeric keypad, a keyboard, or a cursor control device (such as a mouse or joystick), a touch screen display, a remote control, or any other device operable to interact with the inverter controller 300.

[0176] The inverter controller 300 may also or alternatively include a drive unit 306 implemented as a disk or optical drive, flash memory, or any medium capable of storing, encoding, or carrying a set of instructions for execution by the inverter controller 300. The drive unit 306 may include a computer-readable medium 322 in which one or more sets of instructions 324 (e.g., software) may be embedded. Further, the instructions 324 may embody one or more of the methods or logics described herein. The instructions 324 may reside completely or partially within the memory 304 and / or within the processor 302 during execution by the inverter controller 300. The memory 304 and the processor 302 may also include computer-readable media as described above.

[0177] In some systems, the computer-readable medium 322 includes instructions 324 or receives and executes instructions 324 in response to a propagated signal, so that a device connected to the network 370 can transmit voice, video, audio, images, or any other data through the network 370. Further, the instructions 324 can be transmitted or received through the network 370 and / or using the bus 308 via the communication port or interface 320. The communication port or interface 320 can be part of the processor 302 or can be an independent component. The communication port or interface 320 can be formed in software or can be a physical connector in hardware. The communication port or interface 320 can be configured to connect to the network 370, external media, display 310, or any other component in the inverter controller 300, or a combination thereof. The connection to the network 370 can be a physical connection (such as a wired Ethernet connection) or can be established wirelessly, as described below. Similarly, additional connections to other components of the inverter controller 300 can be physical connections or can be established wirelessly. The network 370 can alternatively be directly connected to the bus 308.

[0178] Although the computer-readable medium 322 is shown as a single medium, the term "computer-readable medium" may include a single medium or multiple media (such as a centralized or distributed database and / or associated caches and servers) that store one or more sets of instructions. The term "computer-readable medium" may also include any medium capable of storing, encoding, or carrying a set of instructions for execution by a processor or causing a computer system to perform any one or more of the methods or operations disclosed herein. The computer-readable medium 322 may be non-transitory and may be tangible.

[0179] Computer readable medium 322 may include solid-state memory, such as a memory card or other package that accommodates one or more non-volatile read-only memories. Computer readable medium 322 may be random access memory or other volatile rewritable memory. Additionally or alternatively, computer readable medium 322 may include magneto-optical or optical media, such as a disk or tape or other storage device for capturing carrier signals (such as signals transmitted through a transmission medium). Digital file attachments to emails or other self-contained information archives or archive sets may be considered distribution media as tangible storage media. Therefore, the present disclosure is considered to include any one or more of computer-readable media or distribution media and other equivalents and successor media in which data or instructions may be stored.

[0180] In alternative implementations, dedicated hardware implementations (such as application specific integrated circuits, programmable logic arrays, and other hardware devices) may be constructed to implement one or more of the methods described herein. Applications that may include the apparatus and systems of various implementations may broadly include a variety of electronic and computer systems. One or more implementations described herein may use two or more specific interconnected hardware modules or devices with associated control and data signals that may be transmitted between and through the modules or as part of an application specific integrated circuit to implement functionality. Thus, the present system encompasses software, firmware, and hardware implementations.

[0181] The inverter controller 300 may be connected to a network 370. The network 370 may define one or more networks, including wired or wireless networks. For example, the wireless network may be a cellular telephone network, an 802.11, 802.16, 802.20, or WiMAX network. Further, such networks may include public networks (such as the Internet), private networks (such as intranets), or combinations thereof and may utilize a variety of networking protocols now available or later developed, including but not limited to TCP / IP-based networking protocols. The network 370 may include a wide area network (WAN) (such as the Internet), a local area network (LAN), a campus area network, a metropolitan area network, a direct connection (such as via a controller area network (CAN), FlexRay, or a combination thereof). TM, Universal Serial Bus (USB) port) or any other network that allows data communication. Network 370 can be configured to couple one computing device to another computing device to enable data communication between the devices. Network 370 can generally be enabled to use any form of machine-readable media to transmit information from one device to another. Network 370 may include a communication method through which information can travel between computing devices. Network 370 can be divided into subnetworks. A subnetwork can allow access to all other components in other components connected to it, or a subnetwork can restrict access between components. Network 370 can be viewed as a public or private network connection, and can include, for example, a virtual private network or encryption or other security mechanisms used on the public Internet.

[0182] According to various implementations of the present disclosure, the methods described herein may be implemented by a software program that can be executed by a computer system. Further, in an exemplary non-limiting implementation, the implementation may include distributed processing, component or object distributed processing, and parallel processing. Alternatively, a virtual computer system process may be constructed to implement one or more of the methods or functionalities described herein.

[0183] Although this specification describes components and functions that can be implemented in a specific implementation with reference to specific standards and protocols, the present disclosure is not limited to such standards and protocols. For example, standards for Internet and other packet-switched network transmissions (e.g., TCP / IP, UDP / IP, HTML, HTTP) represent examples of the prior art. Such standards are periodically replaced by faster or more efficient equivalents having substantially the same functionality. Therefore, alternative standards and protocols having the same or similar functionality as those disclosed herein are considered equivalents thereof.

[0184] It will be appreciated that, in one embodiment, the operations of the methods discussed are performed by an appropriate processor (or processors) of a processing (i.e., computer) system executing instructions (computer readable code) stored in a storage device. It will also be appreciated that the present disclosure is not limited to any particular implementation or programming technique, and that the present disclosure may be implemented using any suitable technique for implementing the functionality described herein. The present disclosure is not limited to any particular programming language or operating system.

[0185] Figure 4 Describes a method for Figure 2An exemplary system infrastructure of a point-of-use switching controller. For a three-phase inverter, each of the upper phase and the lower phase may include three phases related to phases A, B, and C. For example, the upper phase power module 140 may include an upper phase power module 140A for upper phase A, an upper phase power module 140B for upper phase B, and an upper phase power module 140C for upper phase C. The upper phase power module 140A may include a point-of-use upper phase A controller 142A and an upper phase A switching element 144A. The upper phase power module 140B may include a point-of-use upper phase B controller 142B and an upper phase B switching element 144B. The upper phase power module 140C may include a point-of-use upper phase C controller 142C and an upper phase C switching element 144C. Each of the upper phase A switching member 144A, the upper phase B switching member 144B, and the upper phase C switching member 144C may be connected to the motor 190 and the battery 195 . Figure 4 Details of the upper phase power module 140 are depicted. Although not shown, the lower phase power module 145 may include a similar structure as the upper phase power module 140 for the lower phases A, B, and C.

[0186] Figure 5 Describes a method for Figure 4 Example system infrastructure for the upper power module. For example, Figure 5 Additional details of upper phase power module 140A are provided. Although not shown, upper phase power module 140B, upper phase power module 140C, and respective lower phase power modules of lower phase power module 145 may include components related to Figure 5 The upper phase power module 140A shown in FIG. 1 is similar in structure to the upper phase power module 140A shown in FIG. 1. In addition, the terms "upper", "lower", "northern", and "southern" as used in this disclosure are used for reference only, do not limit the elements to a particular orientation, and are generally interchangeable throughout the text. For example, the upper phase power module 140 may be referred to as a lower phase power module, a northern phase power module, a southern phase power module, a first phase power module, or a second phase power module.

[0187] The upper phase power module 140A may include a point-of-use upper phase A controller 142A and an upper phase A switch 144A. The upper phase A switch 144A may include one or more sets of switches. Figure 5As shown, the upper phase A switch 144A may include an upper phase A north switch 144A-N and an upper phase A south switch 144A-S. The point-of-use upper phase A controller 142A may include one or more memories, controllers, or sensors. For example, the point-of-use upper phase A controller 142A may include a communication manager 405, a functional safety controller 410, a test interface and controller 415, a north thermal sensor 420A, a south thermal sensor 420B, a self-test controller 425, a command manager 430, a waveform adjuster 435, a memory 440, a north switch control and diagnostic controller 450N, and a south switch control and diagnostic controller 450S. The point-of-use upper phase A controller 142A may include a controller 405, a functional safety controller 410, a test interface and controller 415, a north thermal sensor 420A, a south thermal sensor 420B, a self-test controller 425, a command manager 430, a waveform adjuster 435, a memory 440, a north switch control and diagnostic controller 450N, and a south switch control and diagnostic controller 450S. Figure 5 More or fewer components than those shown. For example, the point-of-use upper phase A controller 142A may include more or less than two switch controls and diagnostic controllers, and may include more than two thermal sensors.

[0188] The communication manager 405 may control inter-controller communications to and from the point-of-use upper phase A controller 142A and / or may control intra-controller communications between components of the point-of-use upper phase A controller 142A. The functional safety controller 410 may control safety functions of the point-of-use upper phase A controller 142A. For example, the test interface and controller 415 may control test functions of the point-of-use upper phase A controller 142A, such as end-of-line testing in manufacturing. The north thermal sensor 420A may sense the temperature at a first location in the point-of-use upper phase A controller 142A, and the south thermal sensor 420B may sense the temperature at a second location in the point-of-use upper phase A controller 142A. For example, the self-test controller 425 may control self-test functions of the point-of-use upper phase A controller 142A, such as during initialization of the point-of-use upper phase A controller 142A after an inverter 110 power-on event. The command manager 430 may control commands received from the communication manager 405 and issued to the north switch control and diagnostic controller 450N and the south switch control and diagnostic controller 450S. The waveform adjuster 435 may control the waveform timing and shape of the commands received from the communication manager 405 and issued to the north switch control and diagnostic controller 450N and the south switch control and diagnostic controller 450S. The memory 440 may include one or more volatile and non-volatile storage media for the operation of the point-of-use upper phase A controller 142A. The north switch control and diagnostic controller 450N may send one or more signals to the north switch 144A-N to control the operation of the north switch 144A-N, and may receive one or more signals from the north switch 144A-N that provide information about the north switch 144A-N. The south switch control and diagnostic controller 450S may send one or more signals to the south switches 144A-S to control the operation of the south switches 144A-S, and may receive one or more signals from the south switches 144A-S providing information about the south switches 144A-S. As described above, the terms "north" and "south" are used for reference only, and the north switch control and diagnostic controller 450N may send one or more signals to the south switches 144A-S, and the south switch control and diagnostic controller 450S may send one or more signals to the south switches 144A-N.

[0189] Figure 6 Depicted is an exemplary electrical schematic for a power module including a conductive spacer according to one or more embodiments. Figure 7 Depicted is an exemplary architecture for a power module including a conductive spacer according to one or more embodiments.

[0190] As described above, the application of a half-bridge topology for a power module may present difficulties during assembly and may result in lower yields and higher costs. In addition, some devices may face efficiency issues related to paths for heat and current. A power module according to one or more embodiments may overcome these challenges by using a conductive spacer. The spacer may be formed, for example, of copper or another conductive and / or thermally conductive material. The spacer may provide a connector between the first substrate and the second substrate. The spacer may be, for example, 2 mm by 2 mm and may have a thickness similar to that of the die, for example, such as 180 μm. The spacer may be a surface mount component and placed with the SiC MOSFET using the same process. The spacer may replace the wires and clips that may be used in some systems, and the die interconnects may allow the gate, drain, and source to be connected to the same substrate.

[0191] Conductive spacers can be used in half-bridge topologies for power modules, which can provide reduced loop inductance in the device. The reduced loop inductance can in turn provide less ringing and less voltage overshoot. The application of the device can then speed up switching times, reduce power, and provide more current throughput at a given price and performance point.

[0192] The conductive spacer can provide a path for current to flow from the first substrate to the second substrate, thereby allowing the source reference circuit to be assembled to one (e.g., exactly one, only one, or no more than one) substrate. For example, the conductive spacer can be compatible with methods used to form connections to both sides of the die, such as by sintering or soldering interconnects. The conductive spacer can thus allow current to flow between the two substrates, such as Figure 6 shown.

[0193] The power flows in the cooling power module 600 according to one or more embodiments are respectively Figure 6 and Figure 7 6 and 7. As shown, interconnects 610, 620, and 630 may be on a lower or first substrate providing a source plane. Thus, current may flow along path 660 from interconnect 610 from the lower (source) substrate to the upper or second substrate providing a drain plane, through conductive spacer 640 and to the drain of the first set of parallel SiC MOSFETs (e.g., upper phase switch 144). The drains of the first set of parallel SiC MOSFETs may be attached to a first side ( Figure 7 During the first half cycle, current may be switched (by turning on the first set of parallel SiC MOSFETs) through the drain-to-source first set of parallel SiC MOSFETs to the lower (source) substrate, where the source plane on the first or left side of the lower (source) substrate allows current to flow out of interconnect 630 to a load, for example, to motor 190.

[0194] During the next half cycle, current may flow from interconnect 620 along path 670 and along the second side of the lower (source) substrate ( Figure 7 Current can be switched (by turning on the first set of parallel SiC MOSFETs) through the source to drain second set of parallel SiC MOSFETs to the upper (drain) substrate, through the drain plane on the second or right side of the upper (drain) substrate, and through the conductive spacer 650 to the lower (source) substrate and the load.

[0195] If such a half-bridge arrangement is used in an inverter, current can flow through the device to the load in either direction. That is, current can flow through path 660 or path 670, such as Figure 6 shown.

[0196] Figure 8 A cross-sectional view of an exemplary architecture for a power module 800 including a conductive spacer 860 is depicted in accordance with one or more embodiments. The power module 800 may be Figure 8 A double-sided cooled power module according to one or more embodiments is depicted in cross-section.

[0197] The double-sided cooled power module 800 according to one or more embodiments may provide a high current interconnect between a base substrate and a cover substrate for a double-sided cooled power module. However, while some embodiments herein are referred to as "double-sided cooled," it is contemplated that the devices disclosed herein may be used in "single-sided cooled" applications or combined active / passive cooling configurations. Figure 8 As shown, both the upper substrate 805U and the lower substrate 805L are ceramic, for example, a silicon nitride (Si3N4) intermediate layer, with thick metallization, for example, direct bond copper (DBC) or active metal brazing (AMB) 810, which may be employed on the outer and inner surfaces of the ceramic intermediate layer. Each of the metallization layers 810 may include a plurality of conductive regions electrically separated from each other, such as Figure 8 As shown. The power module 800 may include a semiconductor (e.g., silicon carbide (SiC)) die 815 having a drain connection 820 to an upper substrate 805U. A source connection 830 may be attached to a lower substrate 805L. A polyimide or flex circuit 835 including a base polyimide material with an internal copper layer 840 may be used to enable interconnection with a gate connection 825 of the SiC MOSFET 815. Figure 8Other components shown may include a lead frame connection 845 for a positive supply voltage (e.g., from the battery 195) and a lead frame connection 850 for a negative supply voltage. The assembly may be overmolded with a dielectric material 855. The module may include one or more conductive spacers 860 that provide a high current interconnect between the inner surface of the upper substrate 805U and the inner surface of the lower substrate 805L.

[0198] Fig. 9 A single-side cooling heat flow in cross-section is depicted for an exemplary architecture of a power module 800 including a conductive spacer according to one or more embodiments. Fig. 9 As shown, the conductive spacer 860 can allow heat to flow between the upper substrate 805U and the lower substrate 805L.

[0199] like Fig. 9 As shown, if the lower substrate 805L is used only as a heat sink, the heat from the upper substrate 805U has a conduction path to the outer surface of the lower substrate 805L through the various conductive spacers 860, thereby reducing the overall thermal resistance. The thermal path from the upper substrate 805U and SiC MOSFET 815 to the lower substrate 805L is Fig. 9 As shown by arrow 965 in FIG.

[0200] The double-sided cooling power module 800 according to one or more embodiments may include the use of a conductive spacer 860 in combination with a second-level metal (such as polyimide or a flexible circuit 835) to achieve a low inductance half-H-bridge topology. As described above, the configuration of the double-sided cooling power module 800 according to one or more embodiments enables the source reference circuit to be placed on a single substrate (e.g., a first SiC MOSFET 815 having a drain-to-source current path and a second SiC MOSFET 815 having a source-to-drain current path can be similarly placed on a lower substrate serving as a source plane without being inverted relative to each other). Therefore, the configuration allows bottom-up assembly and is compatible with design for manufacturing (DFM) goals. Similarly, the conductive spacer 860 used in this configuration enables all module high current interconnects (e.g., lead frame connector 845 for the positive supply voltage and lead frame connector 850 for the negative supply voltage, or interconnects 610, 620, and 630) to be formed on one substrate (e.g., lower substrate 805L), thereby improving the overall efficiency of the device.

[0201] Fig.10 Depicted are components of a power module having devices on two substrates and components of an exemplary power module having devices on a single substrate in accordance with one or more embodiments. Fig.10Differences in assembly between the apparatus 1005 and the double-sided cooled power module 1045 according to one or more embodiments are depicted.

[0202] Device 1005 may include a device placed on top ( Fig.10 The top) substrate 1010 and the bottom ( Fig.10 Components 1040 on both the top substrate 1030 and the bottom substrate 1030, wherein the assembly includes drain connectors for half of the switching elements and gate / source connectors for half of the switching elements. Compared to the manufacture of independent components, blind interconnection of independent substrates is difficult when the top substrate is assembled to the bottom because the geometry of the interconnects is different. In the device 1005, all source components can be assembled, half of the components can be placed on each of the two substrates, and source and gate connections can be made as shown. Next, one substrate can be flipped, and then the drain connector on the top on one half and the drain connector on the bottom on the other half are formed. The corresponding geometry interconnects must be formed with half of the interconnects on the top and half on the bottom. In the double-sided cooled power module 1045, all MOSFETs can face the same direction. The interconnects formed when assembling the first substrate can be identical. The second substrate can be free of components, and all interconnects formed during substrate-to-substrate attachment can be similar. Conductive spacers 860 can provide electrical connections from one substrate to another.

[0203] In the case of a Fig.10 The top) substrate 1010 and the bottom ( Fig.10 In the device 1005 with components 1040 on both the top substrate 1010 and the bottom substrate 1030, during assembly, the two substrates must be joined face to face so that the necessary electrical connections are made between the components 1040 on the top substrate 1010 and the bottom substrate 1030. For example, the connection between the gates may be only 1 mm by 1 mm, requiring precise alignment of the top substrate 1010 and the bottom substrate 1030. Incorrect alignment during assembly may result in production losses and higher costs. According to one or more embodiments, the double-sided cooled power module 1045, such as Fig.10 As shown, all components can be provided placed on a single (e.g., exactly one, only one, or no more than one) substrate (e.g., such as a top substrate 1050), thereby avoiding problems with improper alignment during assembly when the top substrate 1050 is combined with the bottom substrate 1060.

[0204] Furthermore, the conductive spacer 860 can be both electrically and thermally conductive, thereby providing a heat conduction path from the top substrate 1050 to the bottom substrate 1060. Although the heat path through the conductive spacer 860 may be less efficient than the heat path directly through each substrate, the use of this heat path through the conductive spacer 860 can enable single-sided cooling in lower power applications.

[0205] Further, the conductive spacers 860 used in this configuration may have a small geometry and may use a small amount of additional space in the circuit topology without significantly compromising the drain and source planes, power module size, or power module overall loop inductance.

[0206] Therefore, as described above, using the conductive spacer 860 in the double-sided cooled power module 800 according to one or more embodiments may provide advantages in terms of device efficiency without causing significant detriment.

[0207] Fig.11 Depicted are components of an exemplary power module 1110 including a substrate 1140 and a flexible layer 1150 according to one or more embodiments. For double-sided cooled power modules and switch applications where high power density is desired, a second wiring layer may be employed so that the gate connection does not interfere with (a) the current capability of the source connection, or (b) the thermal performance of the substrate in terms of increasing the thermal resistance of the substrate.

[0208] Fig.11 A layered construction of such a power module according to one or more embodiments is depicted. Fig.11 As shown, a power module 1110 according to one or more embodiments may include a substrate 1140 and a polyimide flexible layer 1150. The flexible layer 1150 may include a second metal layer including a gate wiring 1170. The opening 1160 may receive a gate pad of a die (e.g., a lower phase switch 148). The substrate 1140 may be combined with the flexible layer 1150 to form a flexible portion on a substrate 1180.

[0209] The flexure on substrate 1180 can guide the gate connection without compromising the source connection and can reduce or eliminate cuts in the source plane that might otherwise be needed to guide the gate signal. The flexure on substrate 1180 can reduce the electrical impedance to the source and gate and can eliminate gate voltage excursions and their effects that can be caused by impedance in the source path. Since the connection is formed from polyimide, the flexure on substrate 1180 does not compromise the source thermal path.

[0210] Fig.12A cross-sectional view of an exemplary architecture for a power module including surface mounted components according to one or more embodiments is depicted. According to one or more embodiments, the power module 1200 may employ a second metal layer. Fig.12 As shown, in cross section, the power module 1200 may include an upper substrate 1205U and a lower substrate 1205L, both of which are ceramic, such as silicon nitride (Si3N4), with thick metallization, such as direct bond copper (DBC) or active metal brazing (AMB) 1210. The upper substrate 1205U and the lower substrate 1205L may be similar to the upper substrate 805U and the lower substrate 805L discussed above. The double-sided cooled power module 1200 may further include SiC grains 1215 (e.g., upper phase switch 144), which may have a drain connection 1220 to the upper substrate 1205U. As shown in FIG. Fig.12 As shown, source connector 1230 may be attached to lower substrate 1205L. A polyimide or flex circuit that may include a base polyimide material 1235 having an inner copper layer 1240 and a cover 1245 may provide an interconnect to the gate 1225 of the SiC MOSFET (e.g., as Fig.11 1205U) and a lead frame connection 1260 for the source (lower substrate 1205L). The assembly may be overmolded with a dielectric material 1270. The polyimide layer may provide a through-hole connection 1275 to the source plane and may also provide solder stops 1250 for various components.

[0211] Although the use of a polyimide layer is described as an example implementation, alternative constructions utilizing printed and fired conductive layers (e.g., such as silver (Ag) alloys) may also be used. The double-sided cooled power module 1200 according to one or more embodiments may utilize soldered interconnections of various components, although other methods of interconnecting components, such as sintering, may also be used.

[0212] The double-sided cooled power module 1200 according to one or more embodiments may represent a hybrid dielectric approach to multi-layer board construction, which may be similar in some respects to a rigid-flex construction, but with different materials and purposes. For example, a high current thermally conductive substrate, such as copper bonded DBC or AMB on Si3N4, aluminum nitride (AlN), aluminum oxide 96% (Al2O3), or other ceramics, may be used for thermal performance, and a flexible circuit laminated on top of the substrate may be used for low-level signal interconnects.

[0213] Double-sided cooled power module 1200 (also referred to herein as "flex on substrate" (FoS)) according to one or more embodiments can allow full utilization of the source thermal path by using openings (e.g., openings 1160) in the dielectric (e.g., flex layer 1150) to connect directly to the underlying substrate copper. For example, Fig.11 As shown, a thin layer of polyimide can be routed underneath the die to form the gate connection without interfering with the source.

[0214] In accordance with one or more embodiments, the FoS construction eliminates the need to cut into the source plane with a gate runner, and thus can allow planar copper to be connected directly to the source for a low impedance electrical connection. That is, in some embodiments, the source plane or source material of the substrate and power module does not include any electrical connections to the gate. Such removal of cuts in the source plane can further minimize any warping that may occur due to uneven copper on the front and back sides of the substrate. Thus, the exposed surface of the source material can be substantially continuous and smooth without any cuts, dents, recesses, etc. Fig.11 No cutouts can be seen in the substrate 1140 in FIG.

[0215] In addition, according to one or more embodiments, the FoS construction can further insulate the gate connectors routed under the die, across the die edge (where high cutoff may be required due to the presence of drain voltage), and around the perimeter of the die. The presence of polyimide can increase the dielectric strength at this point, which can reduce the overall thickness and thermal resistance of the assembly.

[0216] According to one or more embodiments, the FoS structure can allow circuits, SiC gates, and other die to reference the source plane to obtain a smaller loop area. The return path of the generated signal can return to the signal source along the source plane that exists below the guide path. That is, according to one or more embodiments, the FoS structure can prevent the destruction of the source plane, which may cause electromagnetic susceptibility problems in some circuits.

[0217] According to one or more embodiments, the FoS construction may further allow for greater trace routing density than conventional DBC or AMB designs, which may require signal routing and may have limited lines and spaces due to copper thickness.

[0218] Fig.13 A cross-sectional view of an exemplary architecture for a power module 1300 including a shifted substrate according to one or more embodiments is depicted. A double-sided cooled power module according to one or more embodiments may represent a general approach and resulting topological shift to maximize the load current capability of high current power modules used in bridge applications such as three-phase traction inverters without compromising double-sided cooling and overall material thickness within the cooling path.

[0219] The limits of any semiconductor power switching device are based on the allowed temperature rise of the die, the temperature capability of the die attach material, and the temperature of the cooling system. The loss of power relative to switching the desired load current affects the conduction thermal resistance and causes a temperature rise at the SiC FET / IGBT junction. This temperature rise must be limited and must be kept within the allowed temperature limits. The limit at the high end may be slightly lower than the maximum die temperature. For example, the module may have transient offsets and temperature sensing accuracy limitations that result in uncertainty in the actual junction temperature, so that power derating needs to be done at about 25 degrees below this maximum. The limit at the low end may be limited by a 65C maximum coolant temperature, but the fluid temperature within the cooling rail may increase so that 75C is the lower limit.

[0220] The straightforward way to extend the limit is to move the upper limit, as it may not be limited by customer requirements but by supplier requirements. For example, some suppliers allow the maximum junction temperature of the die to increase from 175C to 185C, but the die attach and the rest of the thermal stack should be considered.

[0221] Another way to increase current density is to reduce switching losses. SiC die can reduce switching times. However, to take advantage of this improvement, improved gate control is needed. Improved gate control can reduce switching times while controlling overshoot by dynamically controlling gate current during turn-on and turn-off events. The problem of voltage drop across the source plane is inherent at high currents.

[0222] Improved gate control relies on being able to dynamically control current during turn-on and turn-off and requires lower gate loop inductance. In accordance with one or more embodiments, a double-sided cooled power module can employ a second metal layer comprising a polyimide flex material bonded over the source DBC / AMB copper, thereby being able to reduce the loop area for gate current and its return current.

[0223] In double-sided cooling, exposing both the source and drain sides of the die to the heat sink would ideally halve the thermal resistance. However, for a smaller source surface and the drain side having a larger thermal resistance through the device itself, the thermal resistance can be estimated to be six-tenths of a design using drain-side cooling only, as is the case with most power modules. If the magnitude of the thermal resistance of one path out of the die is the length of that thermal path divided by the material conductivity and area, then the only difference considered in addition to the second path for double-sided cooling of the die may be the entire area being unavailable due to the gate. If 75% of the area is available and the thermal resistance is 4 / 3 of the original thermal resistance, then the parallel combination of the two thermal resistances is (4 / 3 / (1+4 / 3)) times the original thermal resistance, or 0.57 of the original single-sided thermal resistance. If 50% of the area is available and the thermal resistance is twice the original thermal resistance, then the parallel combination becomes (2 / (1+2)) times the original thermal resistance, or 0.66 of the original value, with the best combined thermal resistance being 0.5 of the original value.

[0224] The die is a flat, rectangular solid object that may have only two sides for cooling. Some systems cool the drain side of the die because there are no obstructions on this side. However, the source side of the die has some area dedicated to the gate signal and some area for the source. Some systems may use a wire loop from the gate to the drain side substrate to guide the gate signal out while avoiding close proximity to the drain voltage and not contacting the source. This results in high current source connections requiring some space to avoid contact with the wire loop. Any components that are connected in series with the source for electrical connection may increase the thermal resistance of the source connection and increase the total thermal resistance. The use of wire bonds and clips interferes with the ability to use double-sided cooling. Therefore, embodiments of the present disclosure do not use any wire bonds or clips within the power module. The second metal layer that provides the gate connection must not interfere with the thermal path of the source. If the source attachment requires a base to provide clearance for the gate attachment, the increased thermal resistance of the base will offset some of the benefits of double-sided cooling.

[0225] The double-sided cooled power module 1300 according to one or more embodiments can utilize void areas in the polyimide to enable direct connection of the source to the source plane of the DBC while the gate layer is connected to the second metal of the polyimide flex circuit. In general, the reduction in power module thickness and the use of materials with higher thermal conductivity also allow for increased current capabilities. The use of clips and spacers in series with the source and drain connections increases thermal resistance. The use of vias in the DBC copper to route the gate traces increases warping of the substrate that needs to be accommodated at certain points in the thermal stack.

[0226] A double-sided cooled power module according to one or more embodiments can increase the upper temperature limit condition by utilizing a SiC MOSFET with a higher junction temperature to increase the upper temperature limit and increase the grain size to, for example, 5.5 mm x 5.5 mm, and modify the thermal stack so that the material does not exceed the specified capacity. A double-sided cooled power module according to one or more embodiments can utilize an internal ASIC for temperature sensing without the need for custom SiC FETs or thermistors. Such a configuration can support temperature sensing of the upper and lower phases of a half-H switching element without the use of thermistors, which may have poor accuracy. One or more embodiments may use an ASIC to accurately sense temperature, but does not exclude the use of thermistors or SiC / IGBT devices with temperature sensing.

[0227] A double-sided cooled power module according to one or more embodiments can reduce switching losses by adopting an ASIC for dynamic gate control. The power module can further support multiple pins for gate control. A double-sided cooled power module according to one or more embodiments can adopt a second metal layer for gate wiring to achieve dynamic control of the gate voltage. Such a second metal layer can achieve low gate loop inductance and can make the source plane an effective signal return path. Polyimide has an extremely high dielectric breakdown performance of 200kV / mm.

[0228] Double-side cooled power modules according to one or more embodiments can achieve reduced thermal resistance through reduced material thickness and use of high thermal conductivity materials to allow high currents in switching devices. Polyimide avoids attaching drain or source connections to anything other than the DBC, and does not require spacers from the source to the substrate surface or the use of wire bonds or clips. Polyimide can reduce or minimize wiring on the DBC / AMB substrate to avoid warping, thereby achieving planar contact with the thermal rail.

[0229] like Fig.13 As shown, a double-sided cooling power module 1300 according to one or more embodiments may include an upper substrate 1305U and a lower substrate 1305L, both of which are ceramic, for example, silicon nitride (Si3N4), which have a thick metallization, for example, direct bonded copper (DBC) or active metal brazing (AMB) 1310. The double-sided cooling power module 1300 may further include a plurality of (e.g., such as eight) SiC grains 1315, which may each have a drain connection 1320 to the upper substrate 1305U. As shown in FIG. Fig.13As shown, the source connector 1330 may be attached to the lower substrate 1305L. A polyimide or flexible circuit, which may include a base polyimide layer 1335 having an internal copper layer 1340, may provide an interconnect to the gate 1325 of the SiC MOSFET including the SiC die 1315. The polyimide or flexible circuit may further include, for example, surface mount components such as, for example, a temperature sensor, a thermistor, a capacitor, a resistor, or another integrated circuit (IC) such as a gate driver. The double-sided cooled power module may further include a lead frame connector 1345 for the drain (on the upper substrate 1305U) and a lead frame connector 1350 for the source (on the lower substrate 1305L). The assembly may be overmolded with a dielectric material 1355. The polyimide layer 1335 may provide a through-hole connector 1360 to the source plane, and may also provide solder stops 1365 for various components. As shown Fig.13 As shown, the upper substrate 1305U can be offset 1370 from the lower substrate 1305L. Such an offset 1370 can enable the use of thicker lead frames and higher currents. The power leads 1345 and 1350 can be sintered, soldered, or ultrasonically welded to the double-sided cooled power module 1300.

[0230] Fig.14 Depicted are components of an exemplary power module 1300 including a shifted substrate according to one or more embodiments. Fig.14 Depicted are the various layers of a double-sided cooled power module 1300 and the assembly of the layers into a complete device according to one or more embodiments. Fig.14 In the figure, the reference numerals indicate the same Fig.13 The power module 1300 may include a welded preform (or molded part) 1375. Fig.14 As shown, the upper substrate 1305U and the lower substrate 1305L may be assembled separately and then integrated to form the power module 1300 .

[0231] The assembly may include laminating a polyimide film onto a source substrate. The polyimide carrying a second metal may replace a solder mask on the source substrate. The assembly may include using a placed molding rather than a solder printing operation and may provide a high degree of consistency necessary to reduce thickness variation. The placed molding may also allow for the introduction of higher temperature solder. The assembly may include an offset substrate that requires a different fixation during overmolding. The offset substrate may allow for the use of a thicker lead frame that may carry higher currents. The power module 1300 may provide a significant increase in current capability relative to some systems.

[0232] Fig.15 Depicted is a cross-sectional view of an exemplary architecture for a sintered power module including a shifted substrate, according to one or more embodiments. Fig.15 Depicted is a cross-sectional view of a double-sided cooled power module 1500 using sintered components according to one or more embodiments.

[0233] and Fig.13 In contrast to the power module 1300 shown using welded components, Fig.15 The power module 1500 shown shows a sintered assembly and further includes vias 1560 to AMB or DBC copper, one or more sintered preforms 1575, and sintered films 1580. The common elements of the power modules 1300 and 1500 are shown in FIG. Fig.13 The .

[0234] Fig.16A and Fig. 16B Depicted are components of an exemplary sintered power module including a displaced substrate according to one or more embodiments. Fig.16A and Fig. 16B Depicted are various layers of a double-sided cooled power module 1500 using sintered components and assembling the layers into a complete device according to one or more embodiments. Fig.14 As shown, the upper substrate 1305U and the lower substrate 1305L may be assembled separately and then integrated to form the power module 1500 .

[0235] The sintered power module 1500 may have increased interconnect reliability, which may allow the die to maintain higher temperatures for longer periods without inducing creep failure modes. Fig.16A and Fig. 16B Sintering for both the gate and source is depicted compared to some systems that may use a wire bonded gate. Fig. 16B Depicted are openings in the polyimide for the gate and source. The gate may be on an island opened on the first metal (substrate). A second metal gate runner carried by the polyimide may be connected to the island through a via between the first and second metals. The via may provide the same substrate height at the interface between the gate and source, which may avoid compliance at the gate pad relative to the polyimide below the gate.

[0236] Fig.17A cross-sectional view of an exemplary architecture for a power module including a point-of-use switching controller is depicted in accordance with one or more embodiments. One or more embodiments may include a power module (e.g., an upper phase power module 140 and / or a lower phase power module 145) that is configured to accommodate an onboard gate driver (e.g., a point-of-use upper phase B controller 142B), which may also be referred to as a point-of-use switching controller, a point-of-use controller, an internal IC, or an integrated gate driver. The point-of-use controller may improve control of the gate of a power device switch (e.g., an upper phase B switch 144B) of the power module. Improved gate control may reduce switching times while controlling overshoot by dynamically controlling gate current during turn-on and turn-off events. The gate driver may include multiple separately controlled gate drivers (e.g., a north switch control and diagnostic controller 450N and a south switch control and diagnostic controller 450S).

[0237] Improved gate control may rely on being able to dynamically control the current flowing to the gate during the on and off operations of the power switch, and may require low gate loop inductance. One or more embodiments may increase the upper temperature boundary conditions for the power module. For example, one or more embodiments may use SiC MOSFETs with higher junction temperatures to increase the upper temperature limit. The thermal stack may be configured so that the material does not exceed the specified capacity. One or more embodiments may include an internal ASIC (point of use controller) for temperature sensing without the need for custom SiC FETs or thermistors. Therefore, one or more embodiments may support temperature sensing of the upper and lower portions of the semi-H switch. One or more embodiments may use only a point of use controller to accurately sense the temperature. One or more embodiments may additionally or alternatively use a thermistor or SiC / IGBT device with temperature sensing capabilities.

[0238] One or more embodiments may provide a power module that may experience reduced switching losses. One or more embodiments may support multiple pins for gate control.

[0239] Fig.17A power module 1700 is shown including two stacked substrates, including an upper substrate 1705U and a lower substrate 1705L, both of which are ceramic, for example, silicon nitride (Si3N4), with thick metallization, for example, direct bond copper (DBC) or active metal brazing (AMB) 1710 may be employed. The power module 1700 may include a semiconductor (e.g., silicon carbide (SiC)) grain 1715 with a drain connection 1720 to the upper substrate 1705U. A source connection 1730 may be attached to the lower substrate 1705L. A polyimide or flex circuit 1735 including a base polyimide material with an internal copper layer 1740 may be used, thereby enabling interconnection with a gate connection 1725 of a SiC MOSFET and, for example, surface mount components such as an integrated gate driver 1732. Surface mount components for the power module 1700 are not limited to the integrated gate driver 1732 , and other components such as a temperature sensor, a capacitor, or a resistor may be surface mount components.

[0240] For example, power module 1700 may be an implementation of upper phase power module 140 and / or lower phase power module 145. For example, integrated gate driver 1732 may be an implementation of point-of-use upper phase A controller 142A. For example, SiC MOSFET including SiC die 1715 and gate connector 1725 may be an implementation of upper phase A switch 144A.

[0241] The integrated gate driver 1732 may also be mounted to the internal copper layer 1740 carried by the polyimide circuit 1735 via solder bumps 1734. Other items in the power module 1700 may include a conductive spacer 1760 providing a high current interconnect between the upper substrate 1705U and the lower substrate 1705L, a lead frame 1745 connection to the drain of the upper switch (left SiC die 1715), and a lead frame 1750 connection to the source of the lower switch (right SiC die 1715). The assembly may include overmolding with a dielectric material 1755. The polyimide or flex circuit 1735 may provide through-hole connections 1780 to the source plane and solder stops 1782 for various components. The upper substrate 1705U and the lower substrate 1705L may be offset from each other to enable the use of a thicker lead frame, thereby enabling the conduction of higher currents than thin power module designs typically support. The power leads 1745 and 1750 may be sintered, soldered, or ultrasonically welded to the power module 1700 .

[0242] Through-hole connectors 1780 may be used for current sensing. The power module 1700 may incorporate voids in the polyimide or flex circuit 1735 to enhance the epoxy fill beneath the polyimide layer. The power module 1700 may incorporate a second metal layer into the polyimide or flex circuit 1735 to allow circuit interconnection without consuming DBC substrate area in order to maintain a minimum form factor.

[0243] The power and signal connections are shown as utilizing a copper lead frame, but other interconnect methods are also contemplated, such as flex circuits.One or more embodiments may include a power module 1700 that includes an on-substrate buffer network and decoupling capacitors.

[0244] Fig.18 Depicted are components of an exemplary power module including a point-of-use switching controller according to one or more embodiments. Fig.18 Shows the use of Fig.17 A floor plan of possible designs with the same numbering scheme. Fig.18 As shown, power module 1700 can be assembled by adding layers to lower substrate 1705L. The second metal layer within the polyimide can provide signal guidance as fine lines and spaces, which is not possible on the substrate due to the thickness of the metal. The diameter of the solder opening can be about 250 μm. Fig.18 Depicted is an array of circular openings in the bed cover that provide solder stops for the second layer signal.

[0245] Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered exemplary only, with the true scope and spirit of the invention being indicated by the following claims.

Claims

1. A power module, comprising: a first substrate having an outer surface and an inner surface, the first substrate extending from a first longitudinal end toward a second longitudinal end; a power switching element, the power switching element comprising a semiconductor die, the power switching element being coupled to the inner surface of the first substrate; a second substrate having an outer surface and an inner surface, the power switching element being coupled to the inner surface of the second substrate, the second substrate extending from a first longitudinal end toward a second longitudinal end, wherein the first longitudinal end of the first substrate is longitudinally offset from the first longitudinal end of the second substrate; a first conductive spacer coupled to the inner surface of the first substrate and the inner surface of the second substrate; as well as A flexible circuit is coupled to the power switch. 2 . The power module of claim 1 , wherein the first substrate further comprises an intermediate layer between the inner surface and the outer surface, wherein the intermediate layer comprises ceramic, and the outer surface and the inner surface of the first substrate comprise metal.

3. The power module of claim 1, wherein the conductive spacer is coupled to a first portion of the inner surface of the second substrate, and the power switch is coupled to a second portion of the inner surface of the second substrate, wherein the first portion and the second portion are not directly coupled to each other.

4. The power module according to claim 3, further comprising: A second conductive spacer is coupled to the inner surface of the second substrate and to the inner surface of the first substrate. The power module of claim 1 , wherein the semiconductor grains comprise silicon carbide. 6 . The power module of claim 1 , wherein the second substrate further comprises an intermediate layer between the inner surface and the outer surface, wherein the intermediate layer comprises ceramic, and the outer surface and the inner surface of the second substrate comprise metal. 7 . The power module according to claim 1 , wherein the source connector of the power switch is coplanar with the connector. 8 . The power module of claim 1 , wherein the power switch comprises a drain, wherein the drain is coupled to the inner surface of the first substrate. 9 . The power module of claim 1 , wherein the power switch comprises a source, wherein the source is coupled to the inner surface of the second substrate. 10 . The power module of claim 1 , wherein the flexible circuit comprises an insulating material and a conductive material, wherein the inner surface of the second substrate is electrically insulated from the conductive material of the flexible circuit.

11. The power module of claim 1 , wherein the power switch comprises a gate, wherein electrical connections to the gate are contained only within the flexible circuit.

12. The power module of claim 1, wherein the power switch comprises a gate, wherein electrical connections within the power module to the gate are contained solely within the flexible circuit.

13. The power module of claim 1, wherein the power switch comprises a gate, wherein electrical connections within the power module to the gate do not extend through any portion of the second substrate.

14. The power module according to claim 1, further comprising: a first connecting member; a second connection, wherein the power switch comprises a first gate terminal, the power switch being configured to control a first current between the first connection and the second connection based on a first signal to the first gate terminal; as well as A first point-of-use controller is configured to provide the first signal to the first gate terminal to control the first power switch.

15. An inverter comprising the power module according to claim 1.

16. A vehicle comprising the inverter according to claim 15.

17. A power module, comprising: a first substrate having an outer surface and an inner surface, the first substrate extending from a first longitudinal end toward a second longitudinal end; a power switching element, the power switching element comprising a semiconductor grain coupled to the inner surface of the first substrate, wherein the semiconductor grain comprises silicon carbide; a second substrate having an outer surface and an inner surface, the semiconductor die being coupled to the inner surface of the second substrate, the second substrate extending from a first longitudinal end toward a second longitudinal end, wherein the first longitudinal end of the first substrate is longitudinally offset from the first longitudinal end of the second substrate; a first conductive spacer coupled to an inner surface of the first substrate and to the inner surface of the second substrate; a flexible circuit coupled to the semiconductor die; a first connecting member; a second connection, wherein the power switch comprises a first gate terminal, the first power switch being configured to control a first current between the first connection and the second connection based on a first signal to the first gate terminal; as well as A first point-of-use controller is configured to provide the first signal to the first gate terminal to control the first power switch.

18. An inverter comprising the power module according to claim 17.

19. A vehicle comprising the inverter according to claim 18.

20. A power module, comprising: a first substrate having an outer surface and an inner surface, the first substrate extending from a first longitudinal end toward a second longitudinal end; a power switching element, the power switching element comprising a semiconductor grain coupled to the inner surface of the first substrate, wherein the semiconductor grain comprises silicon carbide; a second substrate having an outer surface and an inner surface, the semiconductor die being coupled to the inner surface of the second substrate, the second substrate extending from a first longitudinal end toward a second longitudinal end, wherein the first longitudinal end of the first substrate is longitudinally offset from the first longitudinal end of the second substrate; a first conductive spacer coupled to an inner surface of the first substrate and to the inner surface of the second substrate; a flexible circuit coupled to the semiconductor die; a first connecting member; a second connection, wherein the power switch includes a first gate terminal, the first power switch being configured to control a first current between the first connection and the second connection based on a first signal to the first gate terminal, wherein an electrical connection within the power module to the first gate terminal does not extend through any portion of the second substrate; as well as A first point-of-use controller is configured to provide the first signal to the first gate terminal to control the first power switch.

Images