Tunable device having a FET integrated with a BJT

Patent metadata

Field	Value
Publication number	US-10249617-B2
Application number	US-201615348878-A
Country	US
Kind code	B2
Filing date	Nov 10, 2016
Priority date	Oct 2, 2009
Publication date	Apr 2, 2019
Grant date	Apr 2, 2019

Abstract

A device includes a field effect transistor (FET) integrated with at least a portion of a bipolar junction transistor (BJT), in which a back gate of the FET shares an electrical connection with a base of the BJT, and in which a reverse voltage can be applied to the back gate of the FET.

First claim

What is claimed is:

1. A continuous tunable inductive capacitive resonator comprising:
a bipolar junction transistor including a base and an emitter;
a field effect transistor integrated with at least a portion of the bipolar junction transistor, at least one of a back gate or a front gate of the field effect transistor sharing an electrical connection with the base of the bipolar junction transistor, a reverse voltage applied to the at least one of the back gate or the front gate of the field effect transistor creating a continuously variable capacitance in a channel of the field effect transistor; and
an inductor arranged to experience a capacitance that varies with the reverse voltage applied to the at least one of the back gate or the front gate of the field effect transistor, the front gate of the field effect transistor electrically connected to the back gate of the field effect transistor.

2. The continuous tunable inductive capacitive resonator of claim 1 wherein the reverse voltage applied to the back gate or to the front gate ranges from −0.4 to −5.0 volts.

3. The continuous tunable inductive capacitive resonator of claim 1 wherein the changes in variable capacitance are continuous over a range of the reverse voltage.

4. The continuous tunable inductive capacitive resonator of claim 3 wherein the continuously variable capacitance is a gate capacitance of the field effect transistor.

5. The tunable resonator of claim 1 wherein the field effect transistor further comprises a source and a drain.

6. The continuous tunable inductive capacitive resonator of claim 1 wherein the variable capacitance is achieved with a substantially linear capacitance-voltage response, at least over a predefined voltage range.

7. The continuous tunable inductive capacitive resonator of claim 1 further comprising the inductor connected parallel across the source and drain of the field effect transistor.

8. A continuous tunable inductive capacitive resonator comprising:
a bipolar junction transistor including a base and an emitter;
a field effect transistor integrated with at least a portion of the bipolar junction transistor, at least one of a back gate or a front gate of the field effect transistor sharing an electrical connection with the base of the bipolar junction transistor, a reverse voltage applied to the at least one of the back gate or the front gate of the field effect transistor creating a continuously variable capacitance in a channel of the field effect transistor; and
an inductor arranged to experience a capacitance that varies with the reverse voltage applied to the at least one of the back gate or the front gate of the field effect transistor, the reverse voltage applied to the at least one of the back gate of the field effect transistor or the front gate of the field effect transistor creating a continuously variable inductive capacitance in the channel of the field effect transistor, the channel being formed at least partially in an emitter layer of the bipolar junction transistor.

9. A radio frequency module having a continuous tunable inductive capacitive resonator, the module comprising:
a packaging substrate configured to receive a plurality of components;
a die mounted on the packaging substrate, the die including the continuous tunable inductive capacitive resonator including a bipolar junction transistor, a field effect transistor integrated with at least a portion of the bipolar junction transistor, and an inductor, the field effect transistor including at least one of a back gate or a front gate sharing an electrical connection with a base of the bipolar junction transistor, a reverse voltage being applied to the at least one of the back gate or the front gate of the field effect transistor, the inductor arranged to experience a capacitance that varies with the applied reverse voltage, the front gate of the field effect transistor electrically connected to the back gate of the field effect transistor; and
a plurality of connectors configured to provide electrical connections between the die and the packaging substrate.

10. The radio frequency module of claim 9 wherein the reverse voltage is applied to the front gate of the FET.

11. The radio frequency module of claim 10 wherein the reverse voltage applied to the back gate or to the front gate ranges from −0.4 to −5.0 volts.

12. The radio frequency module of claim 9 wherein the variable capacitance is achieved with a substantially linear capacitance-voltage response, at least over a predefined voltage range.

13. The radio frequency module of claim 9 wherein the changes in the variable capacitance are continuous over a range of the reverse voltage.

14. The radio frequency module of claim 9 implemented as a radio frequency pass gate.

15. The radio frequency module of claim 9 implemented as a power amplifier module.

16. A method of operating a tunable resonator, the method comprising:
applying a reverse voltage to at least one of a back gate or a front gate of a field effect transistor integrated with at least a portion of a bipolar junction transistor, the field effect transistor including a channel having a variable capacitance that changes in response to changes in the reverse voltage, the tunable resonator including the field effect transistor and the bipolar junction transistor further including an inductor arranged to experience a capacitance that varies with the applied reverse voltage, the front gate of the field effect transistor electrically connected to the back gate of the field effect transistor.

17. The method of claim 16 wherein the reverse voltage applied to the back gate or to the front gate ranges from −0.4 to −5.0 volts.

18. The method of claim 16 wherein the changes in the variable capacitance are continuous over a range of the reverse voltage.

19. The method of claim 16 wherein the continuously variable capacitance is a gate capacitance of the field effect transistor.

20. A radio frequency module having a continuous tunable inductive capacitive resonator, the module comprising:
a packaging substrate configured to receive a plurality of components;
a die mounted on the packaging substrate, the die including the continuous tunable inductive capacitive resonator including a bipolar junction transistor, a field effect transistor integrated with at least a portion of the bipolar junction transistor, and an inductor, the field effect transistor including at least one of a back gate or a front gate sharing an electrical connection with a base of the bipolar junction transistor, a reverse voltage being applied to the at least one of the back gate or the front gate of the field effect transistor, the inductor arranged to experience a capacitance that varies with the applied reverse voltage, wherein the reverse voltage applied to the at least one of the back gate of the field effect transistor or the front gate of the field effect transistor creating a continuously variable inductive capacitance in the channel of the field effect transistor, the channel being formed at least partially in an emitter layer of the bipolar junction transistor.

Assignees

• Skyworks Solutions Inc

Inventors

• Li Bin
• Zampardi Jr Peter J
• Metzger Andre G

Classifications

• H03J3/185

  with varactors, i.e. voltage variable reactive diodes · CPC title

• H01L27/0623

  Electricity · mapped topic

• H01L27/0635 Primary

  Electricity · mapped topic

• H01L29/93

  Electricity · mapped topic

• H01L27/0808

  Electricity · mapped topic