Implantable biocompatible SiC sensors

• US 10,278,629 B2
• Filed: 03/12/2013
• Issued: 05/07/2019
• Est. Priority Date: 03/12/2012
• Status: Active Grant

• Current Assignee: Mississippi State University, University of South Florida (State University System of Florida)
• Original Assignee: Mississippi State University, University of South Florida (State University System of Florida)
• Inventors: Afroz, Shamima, Thomas, Sylvia Wilson, Saddow, Stephen E., Mumcu, Gokhan, Topsakal, Erdem
• Primary Examiner(s): Agahi, Puya
• Application Number:
  US14/383,967
• Publication Number:
  US 20150051466A1
• Time in Patent Office: 2,247 Days
• CPC Class Codes: A61B 2562/125 characterised by the manufacture of electrodes
• CPC Class Codes: A61B 2562/18 Shielding or protection of sensors from environmental influences, e.g. protection from mechanical damage
• CPC Class Codes: A61B 5/0002 Remote monitoring of patients using telemetry, e.g. transmission of vital signals via a communication network A61B5/07 takes precedence; transmission systems for measured values G08C; transmission H04B; transmission of digital information H04L; wireless communication networks H04W
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/053 Measuring electrical impedance or conductance of a portion of the body
• CPC Class Codes: A61B 5/076 Permanent implantations telemetry using implanted circuitry A61B5/0031; implanted stimulators for therapy A61N1/3605, A61N1/362, A61N1/372
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/1473 invasive, e.g. introduced into the body by a catheter A61B5/1482 takes precedence
• CPC Class Codes: A61B 5/686 Permanently implanted devices, e.g. pacemakers, other stimulators, biochips A61B5/6861 takes precedence
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 9/0407 Substantially flat resonant element parallel to ground plane, e.g. patch antenna dipole H01Q9/285; monopole H01Q9/40

Abstract

In one embodiment, an implantable biosensor includes a sense antenna comprising a silicon carbide substrate and a radiating electrode formed on the substrate.

Claims

1. An implantable subcutaneous blood glucose level biosensor comprising:

a controller configured to generate a known input signal;

a sense antenna controlled by the controller that is configured to transmit the known input signal into surrounding biomaterial and receive a reflected peak radiation frequency signal from the surrounding biomaterial that is indicative of a blood glucose level within the biomaterial, the sense antenna being a patch antenna comprising a semi-insulating single-crystal silicon carbide substrate composed of 4H-SiC, a radiating electrode comprising a flat rectangular silicon carbide patch formed on a first side of the semi-insulating single-crystal silicon carbide substrate, a feed line extending across the first side of the semi-insulating single-crystal silicon carbide substrate to the radiating electrode, and a ground plane formed on a second side of the semi-insulating single-crystal silicon carbide substrate, wherein the sense antenna is not encased in protective material;

a transmission antenna configured to transmit the reflected peak radiation frequency signal to an external device; and

a power source that provides power to the controller.

2. The implantable biosensor of claim 1, wherein the radiating electrode is composed of doped polycrystalline silicon carbide.

3. The implantable biosensor of claim 1, wherein the radiating electrode is composed of doped 3C-SiC.

4. The implantable biosensor of claim 3, wherein the sense antenna further comprises a polysilicon seed layer provided between the radiating electrode and the silicon carbide substrate.

5. The implantable biosensor of claim 1, wherein the radiating electrode is a doped 4H-SiC homo-epitaxial layer.

6. The implantable biosensor of claim 1, wherein the radiating electrode comprises ion-implanted 4H-SiC.