Haptic Actuators Fabricated by Roll-to-Roll Processing

Abstract

Described is a micro-haptic actuator device that can be fabricated with roll-to-roll MEMS processing techniques. The device includes a first body having a first surface and a second, opposing surface, the body has a chamber defined by at least one interior wall, a piston member disposed in the chamber, physically spaced from the at least one interior wall of the chamber, the piston member having a first surface and a second opposing surface. A membrane layer is disposed over and attached to the first surface of the body, with a portion of the membrane attached to the first surface of the piston member. The device also includes a first electrode supported on a second surface the membrane, and a second body that supports a second electrode, with the second body attached to the second surface of the first body.

1 - 20 . (canceled) 
     
     
         21 . A haptic actuator device comprises:
 a first body layer having a first surface and a second, opposing surface, the first body layer having a chamber defined by at least one interior wall;   a membrane carrying an electrically conductive electrode on a first surface and having a second opposing surface;   a piston member disposed in the chamber, the piston member physically spaced from the at least one interior wall of the chamber, the piston member having a first surface and a second opposing surface;   a first adhesive layer disposed over the first surface of the first body layer, with the first adhesive layer affixing the second, opposing surface of the membrane to the first surface of the piston and to the first body layer;   a second adhesive layer disposed over the second surface of the first body layer; and   a second body layer having a first surface and a second surface, with the second surface of the second body supporting a second electrode, with the first surface of the second body layer attached to the second surface of the first body layer by the second adhesive layer.   
     
     
         22 . The device of  claim 21  wherein the second body layer is a composite second body layer comprising:
 a first layer having first and second surfaces, with the first surface of the first layer affixed to the second surface of the first body layer by the second adhesive layer, and with the first layer having a second chamber defined by at least one second interior wall, which aligns with the chamber defined by the at least one interior wall of the first body layer; 
 a second layer having first and second surfaces, with the second electrode disposed on the second surface of the second layer; and 
 a third adhesive layer affixed to the second surface of the first layer and the first surface of the second layer. 
 
     
     
         23 . The device of  claim 21  wherein the second body layer has a second chamber that is terminated by a floor, with the second body layer attached to the first body layer over the second surface of the first body layer, and with the second body layer having the second electrode. 
     
     
         24 . The device of  claim 21  further comprising:
 a first sealing layer over the first electrode; and 
 a second sealing layer over the second electrode. 
 
     
     
         25 . The device of  claim 21  wherein the haptic actuator device is a first haptic actuator device, and the haptic actuator further comprises:
 at least one addition haptic actuator device disposed in a stack on the first haptic actuator device. 
 
     
     
         26 . The device of  claim 21  wherein the haptic actuator device operates by a voltage that is applied between the first electrode and the second electrode to cause the membrane carrying the first electrode to attract to the second electrode. 
     
     
         27 . The device of  claim 23  wherein a first one of the first electrode and the second electrode is provided with a positive charge and a second, different one of the first electrode and the second electrode is provided with a negative charge. 
     
     
         28 . The device of  claim 27  wherein the positive charge and the negative charges are applied at a voltage value and a slew rate between the first electrode and the second electrode to cause the membrane carrying the first electrode to attract to the second electrode with a striking motion that strikes the floor of the second body layer to produce a vibrational sound. 
     
     
         29 . The device of  claim 28  wherein the voltage value applied is in a range of 500 volts up to 1000 volts. 
     
     
         30 . The device of  claim 26  wherein the voltage applied is a pull-in voltage applied that is reduced to a lower voltage once a highest magnitude of the pull-in voltage is reached, where the pull in voltage is the voltage value required for the membrane to travel approximately two thirds of a distance between the bottom of the piston and top of the second body layer. 
     
     
         31 . The device of  claim 30  wherein the distance between the bottom of the piston and top of the second body layer has been reached, the travel to the striking portion at the bottom of the body layer occurs very rapidly with a concomitant strong vibration. 
     
     
         32 . The device of  claim 21  further comprises:
 an additional mass provided to the piston. 
 
     
     
         33 . The device of  claim 32  wherein the additional mass is provided by the piston having a density greater than a density of the first body layer. 
     
     
         34 . The device of  claim 21  wherein the first body layer has a height in a range of 25 microns to 250 microns and the membrane has a height of about 10 percent of the height of the first body layer. 
     
     
         35 . The device of  claim 26  further comprising:
 an electronic drive circuit having signal lines coupled to the first and second electrodes to produce the voltage between the first electrode and the second electrode. 
 
     
     
         36 . A method of fabricating a micro haptic actuator, the method comprises:
 providing an adhesive layer on a first surface of a first sheet of a flexible material;   clearing the adhesive layer from the first sheet in a region of the first sheet that corresponds a chamber;   patterning the first sheet to provide a piston and the chamber, with the piston disposed in and spaced from walls of the chamber and with the piston having tether elements that tethered piston to remaining portions of the first sheet;   affixing with the patterned adhesive layer, a membrane sheet having a first conductive layer to the piston and remaining portions of the first sheet;   patterning a second chamber in a first surface of a second sheet, with the second sheet supporting a second conductive layer on a second surface; and   affixing with a second adhesive layer, the first surface of the second sheet to a second surface of the first sheet.   
     
     
         37 . The method of  claim 36  wherein the adhesive is a type 1801 adhesive and the material of the first and second sheets is polyethylene terephthalate (PET). 
     
     
         38 . The method of  claim 36  wherein the second sheet is a composite sheet, the method comprising:
 providing a spacer layer having the second chamber; and 
 providing a striking layer for the piston. 
 
     
     
         39 . The method of  claim 36  wherein the second sheet is a single sheet having a recess terminating in a floor that provides a striking layer for the piston. 
     
     
         40 . The method of  claim 36  further comprising:
 removing the tether elements at a subsequent stage of fabrication of the micro haptic actuator.