Silicon microlancet device and method of construction

• US 20020136863A1
• Filed: 03/26/2001
• Published: 09/26/2002
• Est. Priority Date: 03/26/2001
• Status: Abandoned Application

• Current Assignee: Kumetrix Incorporated
• Original Assignee: Kumetrix Incorporated
• Inventors: Subramanian, Kumar, Smart, Wilson, Orloff, Eugene
• Application Number:
  US09/817,567
• Publication Number:
  US 20020136863A1
• Time in Patent Office: Days
• US Class Current: 428/156
• CPC Class Codes: A61B 5/14514 using means for aiding extraction of interstitial fluid, e.g. microneedles or suction
• CPC Class Codes: A61B 5/150022 for capillary blood or interstitial fluid
• CPC Class Codes: A61B 5/150282 for piercing elements, e.g. blade, lancet, canula, needle
• CPC Class Codes: A61B 5/150984 Microneedles or microblades
• CPC Class Codes: Y10T 428/24479 including variation in thickness
• CPC Class Codes: Y10T 428/24802 Discontinuous or differential coating, impregnation or bond [e.g., artwork, printing, retouched photograph, etc.]

Abstract

A minimally intrusive, self-use microlancet device is provided. The microlancet device is capable of piercing a patient'"'"'s skin reliably and virtually painlessly for obtaining a blood sample. The microlancet device comprises a silicon wafer formed into a sharp probe for piercing the patient'"'"'s skin. Also provided is a fabrication method for the microlancet device.

Claims

1. A microlancet device formed of silicon and having a sharp point for piercing the skin of a subject.

2. The microlancet device of claim 1 wherein the microlancet device has a cross section between approximately 50 micrometers and approximately 250 micrometers.

3. The microlancet device of claim 1 wherein the microlancet device has a length between approximately 1 millimeter and approximately 3 millimeters.

4. The microlancet device of claim 1 and further comprising a nitride film deposited on the silicon substrate.

5. The microlancet device of claim 5 wherein the nitride film has a thickness of approximately 2000 Angstroms.

6. The microlancet device of claim 5 and further comprising coating of photoresist on the nitride film.

7. The microlancet device of claim 5 and further comprising removing a portion of the nitride film.

8. The microlancet device of claim 8 wherein the portion of the nitride film is removed by potassium hydroxide.

9. The microlancet device of claim 9 and further comprising a photoresist coating applied to the silicon wafer.

11. The microlancet device of claim 11 and further comprising removing the photoresist coating.

10. The microlancet device of claim 10 and further comprising patterning the silicon wafer with a plasma etching process.

13. The method of claim 13 and further comprising etching the silicon wafer into a microlancet device having a diameter between approximately 50 micrometers and approximately 250 micrometers.

14. The method of claim 13 and further comprising etching the silicon wafer into a microlancet device having a length between approximately 1 millimeter and approximately 3 millimeters.

15. The method of claim 13 and further comprising applying a sulfuric acid/hydrogen peroxide mixture in water to the silicon wafer.

16. The method of claim 13 and further comprising depositing a nitride film on the silicon wafer.

17. The method of claim 17 wherein the nitride film has a thickness of approximately 2000 Angstoms.

18. The method of claim 17 and further comprising applying a coating of photoresist on the nitride film.

19. The method of claim 17 and further comprising removing a portion of the nitride film.

12. A method-of constructing a microlancet device formed of silicon and having a sharp point for piercing the skin of a subject, the method comprising:

providing a silicon substrate; and

plasma etching the silicon substrate into a sharp probe for piercing the patient'"'"'s skin.

22. The method of claim 22 and further comprising patterning the silicon wafer with a plasma etching process.

20. The method of claim 20 and further comprising removing a portion of the nitride film with potassium hydroxide etchant.

21. The method of claim 21 and further comprising applying a photoresist coating to the silicon wafer.

23. The method of claim 23 and further comprising removing the photoresist coating.