Probe device for electrical stimulation and recording of the activity of excitable cells
View Patent ↗A probe device is described having a substrate and a die on top of the substrate. The die has an array of stimulation/recording sites having at least one stimulation means and at least one recording means. The substrate comprising the die is folded into a cylindrical shape or a shape with a conical cross-section and, therefore, limits damage when it is implanted in tissue to be examined or treated, e.g., the brain of a patient in case of a neuro-probe device for use in deep brain stimulation.
1. A probe device for electrical stimulation and recording of activity of excitable cells in brain tissue, the probe device comprising:
a flexible substrate having a first area and comprising an exterior planar surface, wherein the flexible substrate is shaped to minimize brain tissue damage;
a semiconductor die having a second area smaller than the first area and positioned on the exterior planar surface; and
an array of pixels formed on the semiconductor die, wherein each pixel comprises at least one stimulation means and at least one recording means.
2. The probe device of claim 1 , wherein the probe device has one of a substantially cylindrical shape and a shape with a substantially conical cross-section.
3. The probe device of claim 1 , wherein the first area defines a shaft of the probe device and the second area defines an active part of the probe device.
4. The probe device of claim 1 , wherein the die is a silicon die.
5. The probe device of claim 1 , wherein the substrate comprises one of parylene C, parylene N, polyimide, polysiloxane rubber, teflon, a noble metal, titanium, an oxide, Si 3 N 4 , and biocompatible epoxies.
6. The probe device of claim 1 , further comprising a biocompatible insulating coating for protection against corrosion of contacts present on the substrate and on the die.
7. The probe device of claim 1 , wherein the probe device is a neuro-probe device for performing deep brain stimulation.
8. A method for the manufacturing of a probe device for electrical stimulation and recording of activity of excitable cells in brain tissue, the method comprising:
providing a die comprising an array of pixels, wherein the die comprises a semiconductor material, and each pixel comprises at least one stimulation means and at least one recording means;
thinning the die comprising the array of pixels;
providing a flexible substrate comprising an exterior planar surface;
bonding the die comprising the array of pixels onto the exterior planar surface, wherein the substrate has a first area, the die has a second area, and the first area is bigger than the second area; and
shaping the flexible substrate in a manner to minimize damage of the brain tissue when the probe device is implanted.
9. The method of claim 8 , wherein shaping the substrate includes at least one of folding the substrate and bending the substrate.
10. The method of claim 9 , wherein shaping the substrate comprises forming a device with at least one of a substantially cylindrical shape and a shape having a substantially conical cross-section.
11. The method of claim 8 , wherein bonding the die on the substrate is performed by means of wire bonding.
12. The method of claim 8 , wherein bonding the die on the substrate is performed by means of the flip chip technique.
13. The method of claim 8 , further comprising providing a biocompatible insulating coating for protection against corrosion of contacts present on the substrate and on the die.
14. A method for determining a stimulation pattern for application to excitable cells in brain tissue, the method comprising:
providing a probe device comprising:
a flexible substrate having a first area and comprising an exterior planar surface, wherein the flexible substrate is shaped to minimize brain tissue damage;
a semiconductor die having a second area smaller than the first area and positioned on the exterior planar surface; and
an array of pixels formed on the semiconductor die, wherein each pixel comprises at least one stimulation means and at least one recording means;
using the probe device to record electrical activity of excited cells;
making a comparison of the recorded electrical activity to predetermined activity values of the excited cells; and
based on the comparison, determining the stimulation pattern.
15. A computer program product stored on a non-transitory computer-readable medium which when executed on a processing device executes the method of claim 14 .
16. A device for determining a stimulation pattern for application to excitable cells in brain tissue, the device comprising:
a probe device for recording electrical activity of excited cells and generating corresponding activity signals, the probe device comprising:
a flexible substrate having a first area and comprising an exterior planar surface, wherein the flexible substrate is shaped to minimize brain tissue damage;
a semiconductor die having a second area smaller than the first area and positioned on the exterior planar surface; and
an array of pixels formed on the semiconductor die, wherein each pixel comprises at least one stimulation means and at least one recording means;
processing means for making a comparison of the generated activity signals with pre-determined activity signals for the excited cells; and
stimulation pattern determining means for generating, from said comparison, stimulation pattern parameters of the stimulation pattern.
17. The device of claim 16 , wherein the stimulation pattern parameters are selected from the group consisting of frequency, amplitude, and pulse duration.