Tubular resonant filter and method of making a tubular resonant filter

Patent metadata

Field	Value
Publication number	US-10003317-B2
Application number	US-201615092979-A
Country	US
Kind code	B2
Filing date	Apr 7, 2016
Priority date	Apr 8, 2015
Publication date	Jun 19, 2018
Grant date	Jun 19, 2018

Abstract

A tubular resonant filter comprises a multilayer sheet in a rolled configuration comprising multiple turns about a longitudinal axis, where the multilayer sheet includes a strain-relieved layer, a patterned first conductive layer on the strain-relieved layer, an insulating layer on the patterned first conductive layer, and a patterned second conductive layer on the insulating layer and the patterned first conductive layer. The patterned first and second conductive layers and the insulating layer are interrelated to form a rolled-up inductor connected to a rolled-up capacitor on the strain-relieved layer.

First claim

What is claimed is:

1. A tubular resonant filter for a radio frequency integrated circuit (RFIC), the tubular resonant filter comprising:
a multilayer sheet in a rolled configuration comprising multiple turns about a longitudinal axis and having an on-wafer footprint of about 5000 μm 2 or less, the multilayer sheet including:
a strain-relieved layer;
a patterned first conductive layer on the strain-relieved layer;
an insulating layer on the patterned first conductive layer; and
a patterned second conductive layer on the insulating layer and the patterned first conductive layer,
wherein the patterned first and second conductive layers and the insulating layer are interrelated to form a rolled-up inductor connected to a rolled-up capacitor on the strain-relieved layer.

2. The tubular resonant filter of claim 1 , wherein the patterned first conductive layer comprises:
an inductor strip, and
a capacitor bottom plate in electrical contact with the inductor strip,
wherein the inductor strip wraps around the longitudinal axis in the rolled configuration, thereby forming the rolled-up inductor.

3. The tubular resonant filter of claim 2 , wherein the inductor strip is disposed in a serpentine pattern having an amplitude extending in a rolling direction.

4. The tubular resonant filter of claim 2 , wherein the patterned second conductive layer comprises:
a capacitor top plate on a portion of the insulating layer and overlying the capacitor bottom plate,
wherein the capacitor top and bottom plates and the portion of the insulating layer curve around the longitudinal axis in the rolled configuration, thereby forming the rolled-up capacitor.

5. The tubular resonant filter of claim 4 , wherein the multilayer sheet is disposed on a substrate comprising:
two contact pads, at least one of the two contact pads being connected to the inductor strip; and
a common ground portion electrically isolated from the two contact pads.

6. The tubular resonant filter of claim 5 , wherein both of the two contact pads are connected to the inductor strip to form a series connection of the rolled-up inductor, and
wherein a conductive line connects the capacitor top plate to the common ground portion to form a shunt connection of the rolled-up capacitor.

7. The tubular resonant filter of claim 5 , wherein one of the two contact pads is connected to the capacitor bottom plate and one of the two contact pads is connected to the capacitor top plate to form a series connection of the rolled-up capacitor, and
wherein a conductive line connects the inductor strip to the common ground portion to form a shunt connection of the rolled-up inductor.

8. The tubular resonant filter of claim 5 , wherein both of the two contact pads are connected to the inductor strip and the capacitor top or bottom plate to form a series connection of the rolled-up inductor and the rolled-up capacitor,
wherein the multilayer sheet further comprises, on the strain-relieved layer:
an additional inductor strip and an additional conductive line connecting the additional inductor strip to the common ground portion; and
an additional capacitor bottom plate, an additional portion of the insulating layer on the additional capacitor bottom plate, and an additional capacitor top plate on the additional portion of the insulating layer overlying the additional capacitor bottom plate, the additional capacitor top or bottom plate being connected to the common ground portion,

wherein the additional capacitor top and bottom plates and the additional portion of the insulating layer curve around the longitudinal axis in the rolled configuration, thereby forming an additional rolled-up capacitor having a shunt connection, and
wherein the additional inductor strip wraps around the longitudinal axis in the rolled configuration, thereby forming an additional rolled-up inductor having a shunt connection.

9. The tubular resonant filter of claim 8 , wherein the additional inductor strip is part of the patterned first conductive layer and has a shorter length than the inductor strip.

10. The tubular resonant filter of claim 8 , wherein the additional inductor strip is part of the patterned second conductive layer and has a longer length than the inductor strip.

11. The tubular resonant filter of claim 1 , wherein the strain-relieved layer comprises two layers, and wherein, in an unrolled configuration of the multilayer sheet, a top layer of the two layers is in tension and a bottom layer of the two layers is in compression.

12. The tubular resonant filter of claim 11 , wherein each of the two layers comprises non-stoichiometric silicon nitride.

13. The tubular resonant filter of claim 1 , wherein each of the patterned first and second conductive layers comprises one or more materials selected from the group consisting of carbon, silver, gold, aluminum, copper, molybdenum, tungsten, zinc, palladium, platinum, and nickel.

14. The tubular resonant filter of claim 1 , wherein each of the patterned first and second conductive layers comprises a thickness of from about 50 nm to about 250 nm.

15. The tubular resonant filter of claim 1 , wherein the rolled configuration comprises at least about 5 turns about the longitudinal axis.

16. The tubular resonant filter of claim 1 comprising a pass band or cutoff frequency in the range of from about 10 kHz to about 300 GHz.

17. A tubular resonant filter for a radio frequency integrated circuit (RFIC), the tubular resonant filter comprising:
a multilayer sheet in a rolled configuration comprising multiple turns about a longitudinal axis, the multilayer sheet including:
a strain-relieved layer;
a patterned first conductive layer on the strain-relieved layer, the patterned first conductive layer comprising an inductor strip and a capacitor bottom plate in electrical contact with the inductor strip;
an insulating layer on the patterned first conductive layer; and
a patterned second conductive layer on the insulating layer and the patterned first conductive layer, the patterned second conductive layer comprising a capacitor top plate on a portion of the insulating layer and overlying the capacitor bottom plate,
wherein the inductor strip wraps around the longitudinal axis and the capacitor top and bottom plates and the portion of the insulating layer curve around the longitudinal axis to form a rolled-up inductor connected to a rolled-up capacitor.

18. A method of making a tubular resonant filter for a radio frequency integrated circuit (RFIC), the method comprising:
forming a sacrificial layer on a substrate;
forming a strained layer on the sacrificial layer, the strained layer comprising an upper portion under tensile stress and a lower portion under compressive stress, the strained layer being held on the substrate by the sacrificial layer;
forming a patterned first conductive layer on the strained layer, the patterned first conductive layer comprising an inductor strip and a capacitor bottom plate in electrical contact with the inductor strip;
forming an insulating layer on the patterned first conductive layer; and
forming a patterned second conductive layer on the insulating layer and the patterned first conductive layer;
initiating removal of the sacrificial layer from the substrate, thereby releasing an end of the strained layer; and
continuing the removal of the sacrificial layer, thereby allowing the strained layer including the patterned first and second conductive layers and the insulating layer to move away from the substrate and roll up to a rolled configurati

Assignees

• Univ Illinois

Inventors

• Li Xiuling
• Li Moyang
• Huang Wen

Classifications

• H03H2001/0085

  Multilayer, e.g. LTCC, HTCC, green sheets · CPC title

• H03H7/0115 Primary

  comprising only inductors and capacitors (H03H7/075, H03H7/09, H03H7/12, H03H7/13 take precedence) · CPC title

• H03H2001/0042

  Wound, ring or feed-through type capacitor · CPC title

• H03H2001/005

  Wound, ring or feed-through type inductor · CPC title