Force sensing resistor (fsr) with polyimide substrate, systems, and methods thereof

Patent metadata

Field	Value
Publication number	US-2021069582-A1
Application number	US-202016950661-A
Country	US
Kind code	A1
Filing date	Nov 17, 2020
Priority date	Oct 11, 2016
Publication date	Mar 11, 2021
Grant date	—

Abstract

A force sensing resistor (FSR) that is constructed with a first substrate made of polyimide disposed underneath a second substrate that is resistive and flexible. A handheld controller for an electronic system may include the FSR having a first substrate made of polyimide. The FSR may be mounted on a planar surface of a structure within the controller body, such as a structure mounted within a handle of the controller body, and/or a structure that is mounted underneath at least one thumb-operated control that is included on a head of the controller body. The FSR may be configured to measure a resistance value that corresponds to an amount of force applied to an outer surface of the handle and/or an amount of force applied to the at least one thumb-operated control.

First claim

What is claimed is:

1 . A method of manufacturing a force sensing resistor (FSR), the method comprising:
forming a first substrate made of polyimide and having a conductive material disposed on a front surface of the first substrate; providing one or more spacer layers atop the first substrate, leaving a portion of the conductive material uncovered by the one or more spacer layers; and providing a second substrate atop the first substrate such that the one or more spacer layers are interposed between the first substrate and the second substrate, the second substrate being flexible and having resistive material disposed on a back surface of the second substrate.

2 . The method of claim 1 , wherein the conductive material comprises a metal layer.

3 . The method of claim 2 , further comprising etching the metal layer to form interdigitated metal fingers on the front surface of the first substrate.

4 . The method of claim 3 , wherein the metal layer comprises a copper clad layer, and wherein the interdigitated metal fingers comprise interdigitated copper fingers, the method further comprising depositing a layer of gold plating onto the interdigitated copper fingers to create gold-plated fingers.

5 . The method of claim 1 , further comprising providing an actuator on the second substrate.

6 . The method of claim 1 , wherein the providing the one or more spacer layers atop the first substrate comprises:
depositing a coverlay of polyimide on the first substrate at a periphery of the first substrate, the coverlay covering a peripheral portion of the conductive material, wherein the portion of the conductive material comprises a remaining portion of the conductive material that is left uncovered by the coverlay; and depositing a layer of adhesive on the coverlay such that the remaining portion of the conductive material is left uncovered by the layer of adhesive, and such that a section of the coverlay is left uncovered by the layer of adhesive to create an air gap that allows air to ingress or egress from a space between the first substrate and the second substrate.

7 . The method of claim 1 , further comprising, after providing the second substrate atop the first substrate:
wrapping a portion of the first substrate around the second substrate such that the portion of the first substrate is disposed on a front surface of the second substrate; and attaching an actuator to the portion of the first substrate.

8 . The method of claim 1 , wherein, when the FSR is operational, a resistance across output terminals of the FSR varies in response to variable force applied to the FSR.

9 . A method of manufacturing a force sensing resistor (FSR), the method comprising:
forming a first substrate made of polyimide and having a conductive material disposed on a front surface of the first substrate; providing one or more spacer layers atop the first substrate at a periphery of the first substrate; and providing a second substrate atop the first substrate such that a portion of the second substrate is suspended over the first substrate by the one or more spacer layers, the second substrate being flexible and having resistive material disposed on a back surface of the second substrate.

10 . The method of claim 9 , further comprising providing an actuator on the second substrate.

11 . The method of claim 10 , wherein:
an area of the conductive material that is left uncovered by the one or more spacer layers corresponds to an active area of the FSR; and the actuator is concentric with a center of the active area of the FSR.

12 . The method of claim 9 , wherein the conductive material comprises a copper clad layer.

13 . The method of claim 12 , further comprising:
etching the copper clad layer to form interdigitated copper fingers on the front surface of the first substrate; and depositing a layer of gold plating onto the interdigitated copper fingers to create gold-plated fingers.

14 . The method of claim 13 , wherein the providing the one or more spacer layers atop the first substrate comprises:
depositing a coverlay of polyimide on the first substrate at the periphery of the first substrate, the coverlay covering a peripheral portion of the gold-plated fingers and leaving a remaining portion of the gold-plated fingers uncovered by the coverlay; and depositing a layer of adhesive on the coverlay such that the remaining portion of the gold-plated fingers is left uncovered by the layer of adhesive, and such that a section of the coverlay is left uncovered by the layer of adhesive to create an air gap that allows air to ingress or egress from a space between the first substrate and the second substrate.

15 . The method of claim 13 , wherein the etching the copper clad layer comprises removing strips of copper material having a width of 0.2 millimeters (mm) to create a distance of 0.2 mm between pairs of adjacent copper fingers among the interdigitated copper fingers.

16 . A method of manufacturing a force sensing resistor (FSR), the method comprising:
forming a first substrate made of polyimide and having a conductive material disposed on a front surface of the first substrate; and providing a second substrate atop the first substrate such that a center portion of the second substrate is suspended over the first substrate, the second substrate being flexible and having resistive material disposed on a back surface of the second substrate.

17 . The method of claim 16 , wherein the conductive material comprises interdigitated metal fingers, the method further comprising coupling a first output terminal to a first set of the interdigitated metal fingers and a second output terminal to a second set of the interdigitated metal fingers, wherein, when the FSR is operational, a resistance across the first output terminal and the second output terminal varies in response to variable force applied to the FSR.

18 . The method of claim 16 , further comprising, prior to the providing the second substrate atop the first substrate, providing one or more spacer layers atop the first substrate at a periphery of the first substrate.

19 . The method of claim 16 , wherein the conductive material comprises a copper clad layer.

20 . The method of claim 19 , further comprising:
etching the copper clad layer to form interdigitated copper fingers on the front surface of the first substrate; and depositing a layer of gold plating onto the interdigitated copper fingers to create gold-plated fingers.

Assignees

• Valve Corp

Inventors

• Campbell Ian
• Yoo Cheang Tad
• Yang Lawrence
• Mucha Jeffrey Walter

Classifications

• G06F3/0338

  with detection of limited linear or angular displacement of an operating part of the device from a neutral position, e.g. isotonic or isometric joysticks · CPC title

• G06F3/014

  Hand-worn input/output arrangements, e.g. data gloves · CPC title

• G06F3/0416

  Control or interface arrangements specially adapted for digitisers · CPC title

• G06F3/0383

  Signal control means within the pointing device · CPC title

• G06F3/0484

  for the control of specific functions or operations, e.g. selecting or manipulating an object, an image or a displayed text element, setting a parameter value or selecting a range · CPC title