On-chip integrated mixer with balun circuit and method of making the same

Claim 2

A single chip RF mixing device, comprising: first and second MOS transistors, wherein said first and second MOS transistors operate as unbiased transistors; a first balun circuit comprising a first input port for receiving a local oscillator (LO) signal, a first output port for providing a first signal to a gate of said first MOS transistor and a second output port for providing a second signal to a gate of said second MOS transistor, said first balun circuit further comprising a first plurality of inductors and a first plurality of capacitors, wherein said first balun circuit is an unbiased balun; and an RF input port for providing an RF input signal to sources of said first and second MOS transistors; wherein said first and second MOS transistors, said first plurality of inductors, and said first plurality of capacitors are integrated in a silicon-on-insulator substrate within a single chip so as to provide a single chip RF mixing device having a conversion loss of less than approximately 7 dB.

Claim 3

The device of claim 1 , wherein said first plurality of inductors each comprise at least three metal layers separated by intermetal dielectric layers, wherein said at least three metal layers are shorted to one another by means of via holes through said intermetal dielectric layers.

Claim 4

The device of claim 2 wherein a thickness of a top metal layer of said at least three metal layers is approximately 1-6 microns thick, a thickness of a middle layer of said at least three metal layers is approximately 0.6-1 microns thick and a thickness of a bottom layer of said at least three metal layers is approximately 0.6-1 micron thick.

Claim 5

The device of claim 3 wherein the impedance of said first plurality of inductors matches a respective impedance of said gates of said first and second MOS transistors when they are in an ON state and operating in a passive mode so as to provide less than 10 dB return loss.

Claim 6

The device of claim 1 wherein said silicon-on-insulator substrate is an ultra-thin silicon on sapphire (UTSi) substrate.

Claim 7

The device of claim 5 further characterized by a third order non-linearity parameter input IP3 of greater than approximately 30 dBm.

Claim 8

The device of claim 1 further comprising: third and fourth MOS transistors, wherein said third and fourth MOS transistors operate as unbiased transistors; a second balun circuit comprising a second plurality of inductors, a second plurality of capacitors, a second input port for receiving said RF input signal, a third output port for providing a third signal to said sources of said first and second MOS transistors, and a fourth output port for providing a fourth signal to sources of said third and fourth MOS transistors, wherein said second balun circuit is an unbiased balun; wherein said first output port of said first balun circuit further provides said first signal to a gate of said fourth MOS transistor and said second output port of said first balun circuit further provides said second signal to a gate of said third MOS transistor; and wherein said first, second, third and fourth MOS transistors, said first and second plurality of inductors, and said first and second plurality of capacitors are integrated in a silicon-on-insulator substrate within a single chip so as to provide a single chip RF mixing device having a conversion loss of less than approximately 7 dB.

Claim 9

The device of claim 7 , wherein said first and second plurality of inductors each comprise at least three metal layers separated by intermetal dielectric layers, wherein said at least three metal layers are electrically connected to one another by means of via holes through said intermetal dielectric layers.

Claim 10

The device of claim 7 where said first plurality of inductors are designed to match a respective impedance of said gates of said first and second MOS transistors when they are in an ON state and operating in a passive mode so as to provide less than 20 dB return loss.

Claim 11

The device of claim 7 wherein said silicon-on-insulator substrate is an ultra-thin silicon on sapphire (UTSi) substrate.

Claim 12

The device of claim 7 further characterized by a third order non-linearity parameter input IP3 of greater than 30 dBM.

Claim 13

A single chip RF mixing device, comprising: first, second, third and fourth unbiased MOS transistors; a first unbiased balun circuit comprising a first plurality of inductors and a first plurality of capacitors, wherein said first balun receives a local oscillator (LO) signal and generates first and second signals that are 180 degrees out of phase from one another, wherein the first signal is provided to gates of said first and fourth MOS transistors and the second signal is provided to gates of said second and third MOS transistors; a second unbiased balun circuit comprising a second plurality of inductors and a second plurality of capacitors, wherein said second balun receives an RF input signal and generates third and fourth signals that are 180 degrees out of phase from one another, wherein the third signal is provided to sources of said first and second MOS transistors, and the fourth signal is provided to sources of said third and fourth MOS transistors; and wherein said first, second, third and fourth MOS transistors, said first and second plurality of inductors, and said first and second plurality of capacitors are integrated in a silicon-on-insulator substrate within a single chip so as to provide a single chip RF mixing device having a conversion loss of less than approximately 7 dB.

Claim 14

A single chip RF mixing device, comprising: first, second, third and fourth unbiased MOS transistors; a first unbiased balun circuit comprising a first plurality of inductors and a first plurality of capacitors, wherein said first balun receives a local oscillator (LO) signal and generates first and second signals that are 180 degrees out of phase from one another, wherein the first signal is provided to gates of said first and fourth MOS transistors and the second signal is provided to gates of said second and third MOS transistors; a second unbiased balun circuit comprising a second plurality of inductors and a second plurality of capacitors, wherein said second balun receives an RF input signal and generates third and fourth signals that are 180 degrees out of phase from one another, wherein the third signal is provided to sources of said first and second MOS transistors, and the fourth signal is provided to sources of said third and fourth MOS transistors; and wherein said first, second, third and fourth MOS transistors, said first and second plurality of inductors, and said first and second plurality of capacitors are integrated in a silicon-on-insulator substrate within a single chip so as to provide a single chip RF mixing device having a conversion loss of less than approximately 7 dB.