High resistivity metal fan out

• US 10,048,819 B2
• Filed: 09/22/2016
• Issued: 08/14/2018
• Est. Priority Date: 06/06/2008
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Grunthaner, Martin Paul, Huang, Lili
• Primary Examiner(s): Dharia, Prabodh M
• Application Number:
  US15/273,547
• Publication Number:
  US 20170010722A1
• Time in Patent Office: 691 Days
• Field of Search: 345156-184, 178 1801- 1806, 349149, 349150, 361784, 361803
• CPC Class Codes: G06F 2203/04102 Flexible digitiser, i.e. constructional details for allowing the whole digitising part of a device to be flexed or rolled like a sheet of paper
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 2203/04107 Shielding in digitiser, i.e. guard or shielding arrangements, mostly for capacitive touchscreens, e.g. driven shields, driven grounds
• CPC Class Codes: G06F 2203/04113 Peripheral electrode pattern in resistive digitisers, i.e. electrodes at the periphery of the resistive sheet are shaped in patterns enhancing linearity of induced field
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: H05K 1/0289 having a matrix lay-out, i.e. having selectively interconnectable sets of X-conductors and Y-conductors in different planes
• CPC Class Codes: H05K 2201/0108 Transparent
• CPC Class Codes: H05K 3/24 Reinforcing the conductive pattern by solder coating H05K3/3457

Abstract

A touch sensor panel having column traces that can terminate at a short edge of a substrate is disclosed. A flex circuit can have a wide flex circuit portion extending the full width of the short edge that can bond to the bond pads on the top side of the substrate. It can be undesirable to have column traces (e.g., sense lines) and row traces (e.g., drives lines) cross over each other at the bonding area, and it can also be undesirable to have bond pads formed on directly opposing sides of the substrate because such areas can generate unwanted stray mutual capacitance and coupling of signals. Row traces can be routed to the same short edge of the substrate as column traces using wide conductive traces running along the borders of the substrate.

Claims

1. A touch sensor panel comprising:

a substrate including a plurality of first bond pads and a plurality of second bond pads and having a first side and a second side, the first side opposite the second side;

one or more columns formed from a first layer of a first conductive material disposed along the first side of the substrate and electrically coupled to the plurality of first bond pads;

one or more rows formed from a second layer of the first conductive material disposed along the second side of the substrate and electrically coupled to the plurality of second bond pads,

wherein the plurality of first bond pads and the plurality of the second bond pads are located to reduce stray capacitance; and

a flex circuit comprising;

a first portion bonded to the plurality of first bond pads to electrically couple to the one or more columns, and

a second portion bonded to the plurality of second bond pads to electrically couple to the one or more rows,

wherein the plurality of first bond pads and the plurality of second bond pads are located in different locations along a plane of the substrate.

2. The touch sensor panel of claim 1, further comprising:

a shield disposed between the first portion of the flex circuit and the second portion of the flex circuit.

3. The touch sensor panel of claim 1, wherein the flex circuit is configured to bond to an edge of the touch sensor panel.

4. The touch sensor panel of claim 3, wherein the flex circuit extends along substantially the full width of the edge of the touch sensor panel.

5. The touch sensor panel of claim 1, wherein the plurality of first bond pads are in between at least two of the plurality of second bond pads along the plane of the substrate.

6. The touch sensor panel of claim 1, further comprising:

a stackup of a second conductive material disposed on the substrate and on a portion of the one or more rows in one or more border areas of the touch sensor panel to form one or more conductive traces for off-panel connections, wherein at least one trace has segments of varying width along a length of the trace.

7. The touch sensor panel of claim 1, further comprising a passivation layer disposed on at least one of a first side and a second side of the substrate.

8. The touch sensor panel of claim 1, wherein the one or more columns are formed on a first side of the substrate, and the one or more rows are formed on a second side, opposite the first side, of the substrate.

9. The touch sensor panel of claim 1, wherein the substrate comprises a cover material of the touch sensor panel.

10. The touch sensor panel of claim 1, wherein the first layer is separate and distinct from the second layer.

11. The touch sensor panel of claim 1, wherein the first portion of the flex circuit and the second portion of the flex circuit overlap along the plane.

12. A flex circuit, comprising:

a first portion including a plurality of third bond pads, the first portion configured to bond to a plurality of first bond pads located on a first side of a substrate; and

a second portion including a plurality of fourth bond pads, the second portion configured to bond to a plurality of second bond pads located on a second side of the substrate, the second side opposite the first side,

wherein the plurality of first bond pads and the plurality of second bond pads are located in different locations along a plane of the substrate to reduce stray capacitance.

13. The flex circuit of claim 12, wherein the first and second portions are located on separate substrates.

14. The flex circuit of claim 12, wherein when the flex circuit is bonded to the substrate, inner sides of the first and second portions are configured to bond to the substrate.

15. The flex circuit of claim 12, wherein when the flex circuit is bonded to the substrate, the plurality of third bond pads are located between at least two of the plurality of fourth bond pads along the plane of the substrate.

16. The flex circuit of claim 12, wherein the first portion and the second portion overlap along the plane of the substrate.

17. A method of routing a plurality of signals from a plurality of sensors to a plurality of bond pads, the method comprising:

coupling a plurality of columns of the plurality of sensors to a first plurality of bond pads located on a first side of a substrate; and

coupling a plurality of rows of the plurality of sensors to a second plurality of bond pads located on a second side of the substrate, the second side opposite the first side,

wherein the plurality of first bond pads and the plurality of second bond pads are located in different locations along a plane of the substrate to reduce stray capacitance.

18. The method of claim 17, further comprising:

bonding a first portion of a flex circuit to the first plurality of bond pads; and

bonding a second portion of the flex circuit to the second plurality of bond pads.

19. The method of claim 17, wherein coupling the plurality of columns and coupling the plurality of rows include locating the plurality of first bond pads between at least two of the plurality of second bond pads along the plane of the substrate.

20. The method of claim 17, further comprising:

coupling the plurality of rows to a stackup of a second conductive material disposed on the substrate in one or more border areas of the substrate to form one or more conductive traces, wherein at least one trace has segments of varying width along the length of the panel.