Patent ID: 12199088

DETAILED DESCRIPTION

The following description is of the best-contemplated mode of carrying out the invention. This description is made for the purpose of illustrating the general principles of the invention and should not be taken in a limiting sense. The scope of the invention is determined by reference to the appended claims.

In order to suppress the phenomenon of high-frequency oscillation in the package structure, the present invention provides a package structure with an electrostatic discharge protection component in a specific connection manner. Therefore, the package structure can not only greatly reduce parasitic inductance, but also resist electrostatic discharge (ESD) pulse, so that the electronic device can operate normally, and its reliability can be improved.

Referring toFIGS.1A and1B, in accordance with one embodiment of the present invention, a package structure10is provided.FIG.1Ais a stereoscopic view of the package structure10.FIG.1Bis a top view of the package structure10.

As shown inFIGS.1A and1B, the package structure10includes a leadframe12, a gallium nitride (GaN) power device14and an electrostatic discharge protection component16. The leadframe12includes a gate pad12a, a source pad12b, a drain pad12cand a Kelvin source pad12d, which are disposed on the leadframe12. The GaN power device14has a gate end14a, a first source end14b, a second source end14cand a drain end14d. The GaN power device14is disposed on the source pad12bof the leadframe12. The electrostatic discharge protection component16includes a first pad16adisposed on it. The electrostatic discharge protection component16is disposed on the source pad12bof the leadframe12. The first source end14bof the GaN power device14is electrically connected to the Kelvin source pad12dof the leadframe12. The second source end14cof the GaN power device14is electrically connected to the source pad12bof the leadframe12. The drain end14dof the GaN power device14is electrically connected to the drain pad12cof the leadframe12. Specifically, the gate end14aof the GaN power device14is electrically connected to the first pad16aof the electrostatic discharge protection component16. The first pad16aof the electrostatic discharge protection component16is electrically connected to the gate pad12aof the leadframe12. InFIGS.1A and1Bfor example, the first source end14bof the GaN power device14is electrically connected to the Kelvin source pad12dof the leadframe12by a conductive wire18a. The second source end14cof the GaN power device14is electrically connected to the source pad12bof the leadframe12by a conductive wire18b. The drain end14dof the GaN power device14is electrically connected to the drain pad12cof the leadframe12by a conductive wire18c. The gate end14aof the GaN power device14is electrically connected to the first pad16aof the electrostatic discharge protection component16by a conductive wire18d. The first pad16aof the electrostatic discharge protection component16is electrically connected to the gate pad12aof the leadframe12by a conductive wire18e.

In some embodiments, the leadframe12is made of metal, such as copper or other appropriate metal materials. In some embodiments, the gate pad12a, the source pad12b, the drain pad12cand the Kelvin source pad12dare made of metal, such as silver or other appropriate metal materials.

InFIGS.1A and1B, the electrostatic discharge protection component16is a vertical component. In some embodiments, the capacitance value of the electrostatic discharge protection component16is greater than or equal to about 30 nC. In some embodiments, the operating voltage of the electrostatic discharge protection component16is greater than about or equal to 6V. In some embodiments, the electrostatic discharge protection component16includes a Zener diode, or a transient voltage suppressor (TVS) diode.

Referring toFIGS.2A and2B, in accordance with one embodiment of the present invention, a package structure10is provided.FIG.2Ais a stereoscopic view of the package structure10.FIG.2Bis a top view of the package structure10.

As shown inFIGS.2A and2B, the package structure10includes a leadframe12, a gallium nitride (GaN) power device14and an electrostatic discharge protection component16. The leadframe12includes a gate pad12a, a source pad12b, a drain pad12cand a Kelvin source pad12ddisposed on it. The GaN power device14has a gate end14a, a first source end14b, a second source end14cand a drain end14d. The GaN power device14is disposed on the source pad12bof the leadframe12. The electrostatic discharge protection component16includes a first pad16adisposed on it. The electrostatic discharge protection component16is disposed on the source pad12bof the leadframe12. The first source end14bof the GaN power device14is electrically connected to the Kelvin source pad12dof the leadframe12. The second source end14cof the GaN power device14is electrically connected to the source pad12bof the leadframe12. The drain end14dof the GaN power device14is electrically connected to the drain pad12cof the leadframe12. Specifically, the gate end14aof the GaN power device14is electrically connected to the gate pad12aof the leadframe12. The first pad16aof the electrostatic discharge protection component16is electrically connected to the gate pad12aof the leadframe12by a plurality of conductive wires. InFIGS.2A and2B, for example, the first source end14bof the GaN power device14is electrically connected to the Kelvin source pad12dof the leadframe12by a conductive wire18a. The second source end14cof the GaN power device14is electrically connected to the source pad12bof the leadframe12by a conductive wire18b. The drain end14dof the GaN power device14is electrically connected to the drain pad12cof the leadframe12by a conductive wire18c. The gate end14aof the GaN power device14is electrically connected to the gate pad12aof the leadframe12by a conductive wire18d. The first pad16aof the electrostatic discharge protection component16is electrically connected to the gate pad12aof the leadframe12by two conductive wires (18eand18f). In some embodiments, the first pad16aof the electrostatic discharge protection component16is electrically connected to the gate pad12aof the leadframe12by other appropriate number of conductive wires, for example, two or more.

In some embodiments, the leadframe12is made of metal, such as copper or other appropriate metal materials. In some embodiments, the gate pad12a, the source pad12b, the drain pad12cand the Kelvin source pad12dare made of metal, such as silver or other appropriate metal materials.

InFIGS.2A and2B, the electrostatic discharge protection component16is a vertical component. In some embodiments, the capacitance value of the electrostatic discharge protection component16is greater than or equal to about 30 nC. In some embodiments, the operating voltage of the electrostatic discharge protection component16is greater than or equal to 6V. In some embodiments, the electrostatic discharge protection component16includes a Zener diode, or a transient voltage suppressor (TVS) diode.

Referring toFIGS.3A and3B, in accordance with one embodiment of the present invention, a package structure10is provided.FIG.3Ais a stereoscopic view of the package structure10.FIG.3Bis a top view of the package structure10.

As shown inFIGS.3A and3B, the package structure10includes a leadframe12, a gallium nitride (GaN) power device14and an electrostatic discharge protection component16. The leadframe12includes a gate pad12a, a source pad12b, a drain pad12cand a Kelvin source pad12ddisposed on it. The GaN power device14has a gate end14a, a first source end14b, a second source end14cand a drain end14d. The GaN power device14is disposed on the source pad12bof the leadframe12. The electrostatic discharge protection component16includes a first pad16aand a second pad16bdisposed on it. The first pad16aand the second pad16bare disposed on the same surface of the electrostatic discharge protection component16. The electrostatic discharge protection component16is disposed on the source pad12bof the leadframe12. The first source end14bof the GaN power device14is electrically connected to the Kelvin source pad12dof the leadframe12. The second source end14cof the GaN power device14is electrically connected to the source pad12bof the leadframe12. The drain end14dof the GaN power device14is electrically connected to the drain pad12cof the leadframe12. Specifically, the gate end14aof the GaN power device14is electrically connected to the first pad16aof the electrostatic discharge protection component16. The first pad16aof the electrostatic discharge protection component16is electrically connected to the gate pad12aof the leadframe12. The second pad16bof the electrostatic discharge protection component16is electrically connected to the source pad12bof the leadframe12. InFIGS.3A and3B, for example, the first source end14bof the GaN power device14is electrically connected to the Kelvin source pad12dof the leadframe12by a conductive wire18a. The second source end14cof the GaN power device14is electrically connected to the source pad12hof the leadframe12by a conductive wire18b. The drain end14dof the GaN power device14is electrically connected to the drain pad12cof the leadframe12by a conductive wire18c. The gate end14aof the GaN power device14is electrically connected to the first pad16aof the electrostatic discharge protection component16by a conductive wire18d. The first pad16aof the electrostatic discharge protection component16is electrically connected to the gate pad12aof the leadframe12by a conductive wire18e. The second pad16bof the electrostatic discharge protection component16is electrically connected to the source pad12bof the leadframe12by a conductive wire18g.

In some embodiments, the leadframe12is made of metal, such as copper or other appropriate metal materials. In some embodiments, the gate pad12a, the source pad12b, the drain pad12cand the Kelvin source pad12dare made of metal, such as silver or other appropriate metal materials.

InFIGS.3A and3B, the electrostatic discharge protection component16is a lateral component. In some embodiments, the capacitance value of the electrostatic discharge protection component16is greater than or equal to about 30 nC. In some embodiments, the operating voltage of the electrostatic discharge protection component16is greater than or equal to 6V. In some embodiments, the electrostatic discharge protection component16includes a Zener diode, or a transient voltage suppressor (TVS) diode.

Referring toFIGS.4A and4B, in accordance with one embodiment of the present invention, a package structure10is provided.FIG.4Ais a stereoscopic view of the package structure10.FIG.4Bis a top view of the package structure10.

As shown inFIGS.4A and4B, the package structure10includes a leadframe12, a gallium nitride (GaN) power device14, and an electrostatic discharge protection component16. The leadframe12includes a gate pad12a, a source pad12b, a drain pad12c, and a Kelvin source pad12ddisposed on it. The GaN power device14has a gate end14a, a first source end14b, a second source end14c, and a drain end14d. The GaN power device14is disposed on the source pad12bof the leadframe12. The electrostatic discharge protection component16includes a first pad16aand a second pad16bdisposed on it. The first pad16aand the second pad16bare disposed on the same surface of the electrostatic discharge protection component16. The electrostatic discharge protection component16is disposed on the source pad12bof the leadframe12. The first source end14bof the GaN power device14is electrically connected to the Kelvin source pad12dof the leadframe12. The second source end14cof the GaN power device14is electrically connected to the source pad12bof the leadframe12. The drain end14dof the GaN power device14is electrically connected to the drain pad12cof the leadframe12. Specifically, the gate end14aof the GaN power device14is electrically connected to the gate pad12aof the leadframe12. The first pad16aof the electrostatic discharge protection component16is electrically connected to the gate pad12aof the leadframe12by a plurality of conductive wires. The second pad16bof the electrostatic discharge protection component16is electrically connected to the source pad12bof the leadframe12. InFIGS.4A and4B, for example, the first source end14bof the GaN power device14is electrically connected to the Kelvin source pad12dof the leadframe12by a conductive wire18a. The second source end14cof the GaN power device14is electrically connected to the source pad12bof the leadframe12by a conductive wire18b. The drain end14dof the GaN power device14is electrically connected to the drain pad12cof the leadframe12by a conductive wire18c. The gate end14aof the GaN power device14is electrically connected to the gate pad12aof the leadframe12by a conductive wire18d. The first pad16aof the electrostatic discharge protection component16is electrically connected to the gate pad12aof the leadframe12by two conductive wires (18eand18f). In some embodiments, the first pad16aof the electrostatic discharge protection component16is electrically connected to the gate pad12aof the leadframe12by other appropriate number of conductive wires, for example, three or more. The second pad16bof the electrostatic discharge protection component16is electrically connected to the source pad12bof the leadframe12by a conductive wire18g.

In some embodiments, the leadframe12is made of metal, such as copper or other appropriate metal materials. In some embodiments, the gate pad12a, the source pad12b, the drain pad12cand the Kelvin source pad12dare made of metal, such as silver or other appropriate metal materials.

In some embodiments, the GaN power device14includes, for example, GaN high-power devices.

InFIGS.4A and4B, the electrostatic discharge protection component16is a lateral component. In some embodiments, the capacitance value of the electrostatic discharge protection component16is greater than or equal to about 30 nC. In some embodiments, the operating voltage of the electrostatic discharge protection component16is greater than about 6V. In some embodiments, the electrostatic discharge protection component16includes a Zener diode, a transient voltage suppressor (TVS) diode, or a metal oxide varistor (MOV).

Comparative Example 1

Simulation of High-Frequency Oscillation Behavior in Package Structure

In this comparative example, the package structure used for simulation is similar to that disclosed byFIG.2A. The distinction between the two is that, in this comparative example, the first pad of the electrostatic discharge protection component is electrically connected to the gate pad of the leadframe by a single conductive wire (not shown). The simulation results are shown inFIGS.5A-5C.FIG.5Ais the oscillation waveform of drain-source current (Ids).FIG.5Bis the oscillation waveform of drain-source voltage (Vds).FIG.5Cis the oscillation waveform of gate-source voltage (Vgs). InFIGS.5A-5C, the left side of the dotted line is the waveform profile when the GaN power device is turned off. The right side of the dotted line is the waveform profile when the GaN power device is turned on.

InFIGS.5A-5C, whether the GaN power device is turned off or turned on, Ids, Vds and Vgs have obvious high-frequency oscillations.

Example 1

Simulation of High-Frequency Oscillation Behavior in Package Structure

In this example, the package structure used for simulation is shown inFIG.1A. That is, the gate end14aof the GaN power device14is electrically connected to the first pad16aof the electrostatic discharge protection component16by the conductive wire18d. The first pad16aof the electrostatic discharge protection component16is electrically connected to the gate pad12aof the leadframe12by the conductive wire18e. The simulation results are shown inFIGS.6A-6C.FIG.6Ais the oscillation waveform of drain-source current (Ids).FIG.6Bis the oscillation waveform of drain-source voltage (Vds).FIG.6Cis the oscillation waveform of gate-source voltage (Vgs). InFIGS.6A-6C, the left side of the dotted line is the waveform profile when the GaN power device is turned off. The right side of the dotted line is the waveform profile when the GaN power device is turned on.

InFIGS.6A-6C, whether the GaN power device is turned off or turned on, no high-frequency oscillation in Ids, Vds and Vgs.

Example 2

Simulation of High-Frequency Oscillation Behavior in Package Structure

In this example, the package structure used for simulation is shown inFIG.2A. That is, the gate end14aof the GaN power device14is electrically connected to the gate pad12aof the leadframe12by the conductive wire18d. The first pad16aof the electrostatic discharge protection component16is electrically connected to the gate pad12aof the leadframe12by the two conductive wires (18eand18f). The simulation results are shown inFIGS.7A-7C.FIG.7Ais the oscillation waveform of drain-source current (Ids).FIG.7Bis the oscillation waveform of drain-source voltage (Vds).FIG.7Cis the oscillation waveform of gate-source voltage (Vgs). InFIGS.7A-7C, the left side of the dotted line is the waveform profile when the GaN power device is turned off. The right side of the dotted line is the waveform profile when the GaN power device is turned on.

InFIGS.7A-7C, whether the GaN power device is turned off or turned on, no high-frequency oscillation in Ids, Vds and Vgs.

In the present invention, the connection manner for the wire-bonding from the gate end of the GaN power device to the electrostatic discharge protection component and from the electrostatic discharge protection component to the gate pad of the leadframe can greatly reduce the inductance in the wire-bonding loop and suppress the high-frequency oscillation of the system. Also, in another connection manner, for example, the wire-bonding from the gate end of the GaN power device to the gate pad of the leadframe and from the electrostatic discharge protection component to the gate pad of the leadframe by a plurality of conductive wires, which can effectively reduce the parasitic inductance caused by the wire-bonding by 20-40% and suppress the high-frequency oscillation of the system. Therefore, the disclosed package structure with the electrostatic discharge protection component in the specific connection manners can not only greatly reduce parasitic inductance, but also resist electrostatic discharge (ESD) pulse, so that the electronic device can operate normally, and its reliability can be improved.

While the invention has been described by way of example and in terms of embodiment, it is to be understood that the invention is not limited thereto. On the contrary, it is intended to cover various modifications and similar arrangements (as would be apparent to those skilled in the art). Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.