FABRICATION OF TOUCH, HANDWRITING AND FINGERPRINT SENSOR

• US 20120090757A1
• Filed: 10/11/2011
• Published: 04/19/2012
• Est. Priority Date: 10/18/2010
• Status: Abandoned Application

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Buchan, Nicholas Ian, Petersen, Kurt Edward, Ganapathi, Srinivasan Kodaganallur
• Application Number:
  US13/271,054
• Publication Number:
  US 20120090757A1
• Time in Patent Office: Days
• US Class Current: 156/60
• CPC Class Codes: G02B 26/0833 the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD G02B26/0825 takes precedence; micromechanical devices in general B81B
• CPC Class Codes: G06F 21/32 using biometric data, e.g. fingerprints, iris scans or voiceprints
• CPC Class Codes: G06F 21/83 input devices, e.g. keyboards, mice or controllers thereof
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 2203/04106 Multi-sensing digitiser, i.e. digitiser using at least two different sensing technologies simultaneously or alternatively, e.g. for detecting pen and finger, for saving power or for improving position detection
• CPC Class Codes: G06F 3/03547 Touch pads, in which fingers can move on a surface
• CPC Class Codes: G06F 3/04144 using an array of force sensing means position sensing using the local deformation of sensor cells G06F3/0447
• CPC Class Codes: G06F 3/04146 using pressure sensitive conductive elements delivering a boolean signal and located between crossing sensing lines, e.g. located between X and Y sensing line layers
• CPC Class Codes: G06F 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184
• CPC Class Codes: G06F 3/044 by capacitive means
• 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: G06F 3/0447 Position sensing using the local deformation of sensor cells
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact
• CPC Class Codes: G06V 40/1306 non-optical, e.g. ultrasonic or capacitive sensing
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor
• CPC Class Codes: Y10T 29/49124 On flat or curved insulated base, e.g., printed circuit, etc.

Abstract

Fabrication methods for combined sensor devices include substantially transparent substrates and materials to increase the optical performance of underlying displays. A substantially transparent elastomeric material may be disposed between the substantially transparent substrates. Some fabrication processes utilize flexible substrates for at least a portion of the sensor device, and lend themselves to roll-to-roll processing for low cost.

Claims

1. A method, comprising:

depositing a first layer of substantially transparent conductive material on a first substantially transparent substrate, wherein depositing the first layer involves forming a first plurality of substantially transparent electrodes in a first region of the first substrate and forming a second plurality of substantially transparent electrodes in a second region of the first substrate;

forming a layer of resistive material on the first layer of substantially transparent conductive material, wherein the forming includes forming a first plurality of resistors on some, but not all, of the first plurality of electrodes and forming a second plurality of resistors on the second plurality of electrodes;

depositing a second layer of substantially transparent conductive material on a second substantially transparent and flexible substrate, wherein depositing the second layer involves forming a third plurality of substantially transparent electrodes in a first region of the second substrate and forming a fourth plurality of substantially transparent electrodes in a second region of the second substrate with a pitch that is substantially the same as that of the second plurality of electrodes;

forming a substantially transparent elastomeric material in the first region of the first substrate; and

attaching the second substrate to the elastomeric material.

2. The method of claim 1, further including forming a force-sensitive resistor material between the second plurality of electrodes and the fourth plurality of electrodes.

3. The method of claim 1, wherein a first index of refraction of the first substrate substantially matches a second index of refraction of the elastomeric material.

4. The method of claim 1, wherein an index of refraction of the elastomeric material substantially matches an index of refraction of the second substrate.

5. The method of claim 1, wherein a modulus of elasticity of the elastomeric material is substantially lower than a modulus of elasticity of the first substrate.

6. The method of claim 1, further including forming the elastomeric material on the first electrodes having the first plurality of resistors deposited thereon.

7. The method of claim 1, further including forming the elastomeric material on the first electrodes not having the first plurality of resistors deposited thereon.

8. The method of claim 1, further including forming a force-sensitive resistor material between the first plurality of electrodes and the third plurality of electrodes.

9. The method of claim 1, further including attaching the first substantially transparent substrate to a display device.

10. The method of claim 1, further including configuring a sensor control system for communication with the first and third pluralities of substantially transparent electrodes.

11. The method of claim 1, wherein at least the depositing involves a roll-to-roll manufacturing process.

12. The method of claim 1, further including applying an adhesive layer to the elastomeric material, but not to the resistive material, prior to the attaching process.

13. The method of claim 6, wherein forming the elastomeric material on the first electrodes having the first plurality of resistors deposited thereon involves forming the elastomeric material on the first electrodes not having the first plurality of resistors deposited thereon, further including removing the elastomeric material from the first electrodes having the first plurality of resistors deposited thereon.

14. The method of claim 10, further including configuring the sensor control system for communication with the second and fourth pluralities of substantially transparent electrodes.

15. The method of claim 10, further including configuring the sensor control system for communication with a processor of a display device.

16. The method of claim 10, further including configuring the sensor control system for processing handwriting and touch sensor data according to electrical signals received from the first and third pluralities of substantially transparent electrodes.

17. The method of claim 13, wherein the removing involves removing the elastomeric material from less than 5% of the first region.

18. The method of claim 14, further including configuring the sensor control system for processing fingerprint sensor data according to electrical signals received from the second and fourth pluralities of substantially transparent electrodes.

19. The method of claim 16, wherein configuring the sensor control system for processing handwriting and touch sensor data involves configuring the sensor control system for projected capacitive touch sensing.

20. The method of claim 16, wherein configuring the sensor control system for processing handwriting and touch sensor data involves configuring the sensor control system for resistive handwriting sensing.

21. The method of claim 16, wherein configuring the sensor control system for processing handwriting and touch sensor data involves configuring the sensor control system for capacitive handwriting sensing.

22. A method, comprising:

depositing a first layer of substantially transparent conductive material on a first substantially transparent substrate, wherein depositing the first layer involves forming a first plurality of substantially transparent electrodes in a first region of the first substrate and forming a second plurality of substantially transparent electrodes in a second region of the first substrate, the second plurality of electrodes being spaced more closely than the first plurality of electrodes;

forming a layer of resistive material on the first layer of substantially transparent conductive material, wherein the forming includes forming a first plurality of resistors on some, but not all, of the first plurality of electrodes and forming a second plurality of resistors on the second plurality of electrodes;

depositing a second layer of substantially transparent conductive material on a second substantially transparent and flexible substrate, wherein depositing the second layer involves forming a third plurality of substantially transparent electrodes in a first region of the second substrate and forming a fourth plurality of substantially transparent electrodes in a second region of the second substrate with a pitch that is substantially the same as that of the second plurality of electrodes;

forming a substantially transparent elastomeric material in the first region of the first substrate; and

attaching the second substrate to the elastomeric material.

23. The method of claim 22, wherein an index of refraction of the first substrate substantially matches an index of refraction of the elastomeric material.

24. The method of claim 22, wherein a modulus of elasticity of the elastomeric material is substantially lower than a modulus of elasticity of the first substrate.

25. The method of claim 22, wherein forming the substantially transparent elastomeric material involves substantially filling a space between only a portion of the first plurality of electrodes and the third plurality of electrodes with the elastomeric material.

26. The method of claim 22, wherein forming the substantially transparent elastomeric material involves substantially filling a space between substantially all of the first plurality of electrodes and the third plurality of electrodes with the elastomeric material.

27. The method of claim 22, further including forming substantially transparent and force-sensitive resistor material extending from the second plurality of electrodes to the fourth plurality of electrodes.

28. The method of claim 23, wherein the index of refraction of the elastomeric material substantially matches an index of refraction of the second substrate.

29. The method of claim 24, wherein the modulus of elasticity of the elastomeric material is between about 0.5 and 50 megapascals.

30. The method of claim 24, wherein the modulus of elasticity of the first substrate is between about 0.5 and 5.0 gigapascals.