Silicon nitride window for microsampling device and method of construction

• US 20020136667A1
• Filed: 03/26/2001
• Published: 09/26/2002
• Est. Priority Date: 03/26/2001
• Status: Active Grant

• Current Assignee: Kumetrix Incorporated
• Original Assignee: Kumetrix Incorporated
• Inventors: Kanu, Asikeh S., Subramanian, Kumar, Smart, Wilson
• Granted Patent: US 6,896,850 B2
• Time in Patent Office: Days
• US Class Current: 422/100
• CPC Class Codes: B81B 3/0035 Constitution or structural means for controlling the movement of the flexible or deformable elements
• CPC Class Codes: G01N 2021/0346 Capillary cells; Microcells
• CPC Class Codes: G01N 21/03 Cuvette constructions
• CPC Class Codes: Y10T 436/25 including sample preparation
• CPC Class Codes: Y10T 436/25625 Dilution
• CPC Class Codes: Y10T 436/25875 Gaseous sample or with change of physical state

Abstract

A silicon nitride cuvette window for a microsampling device and method of construction are provided. The sample to be analyzed is drawn into the cuvette of the microsampling device. The silicon nitride window permits optical measurements to be made on analytes contained within the cuvette.

Claims

1. ) A microsampling device comprising:

a substrate defining a microsampler chamber; and

a cuvette window formed of silicon nitride.

2. ) The device of claim 1 wherein the substrate is silicon.

3. ) The device of claim 2 wherein the silicon substrate has a thickness of approximately 500 micrometers.

4. ) The device of claim 1 wherein the silicon nitride window has a thickness of approximately 0.01 to 5 micrometers.

5. ) The device of claim 1 wherein the chamber has a volume of less than 1 micrometer.

6. ) A method of constructing a cuvette window in the microsampler chamber of a microsampling device, the method comprising

providing a silicon wafer having a top surface and a bottom surface;

etching a patterned depression in the top surface of the silicon wafer thereby defining the microsampler chamber;

depositing a silicon nitride film on the top surface of the silicon wafer; and

etching a patterned depression in the bottom surface of the silicon wafer and exposing the silicon nitride film forming the window.

7. ) The method of claim 6 wherein the silicon wafer has a thickness of approximately 500 micrometers.

8. ) The method of claim 6 wherein the silicon nitride film has a thickness of approximately 0.01 to 5 micrometers.

9. ) A silicon device comprising:

a silicon substrate defining a cuvette; and

a cuvette window formed of silicon nitride.

10. ) The device of claim 9 wherein the silicon nitride window has a thickness of approximately 0.01 to 5 micrometers.

11. ) A method of constructing a window in the cuvette of a silicon device, the method comprising

providing a silicon substrate having a top surface and a bottom surface;

etching a patterned depression in the top surface of the silicon wafer thereby defining the cuvette;

depositing a silicon nitride film on the top surface of the silicon wafer; and

etching a patterned depression in the bottom surface of the silicon wafer and exposing the silicon nitride film forming the window.

12. ) The method of claim 12 wherein the substrate is a silicon wafer.

13. ) The method of claim 12 wherein the silicon nitride film has a thickness of approximately 0.01 to 5 micrometers.