MEMS spectrometer and sensing systems therefrom

• US 8,390,806 B1
• Filed: 05/21/2010
• Issued: 03/05/2013
• Est. Priority Date: 05/21/2009
• Status: Active Grant

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Subramanian, Suresh
• Primary Examiner(s): Geisel, Kara E
• Assistant Examiner(s): BOLOGNA, DOMINIC JOSEPH
• Application Number:
  US12/785,218
• Time in Patent Office: 1,019 Days
• Field of Search: 356300-334
• US Class Current: 356/328
• CPC Class Codes: G01J 3/0259 Monolithic
• CPC Class Codes: G01N 21/658 enhancement Raman, e.g. surface plasmons

Abstract

A MEMS spectrometer includes an optical substrate having a first face and a second face. A first semiconductor substrate is attached to the first face and includes a slit for passing incident light to the optical substrate, at least one integrated reflective grating, and at least one integrated detector array. A second semiconductor substrate is attached to the second face of the optical substrate and includes at least a first integrated mirror and a second integrated mirror. The first integrated mirror is positioned to receive the incident light transmitted by the optical substrate and to provide reflected light, and the integrated reflective grating, second integrated mirror and integrated detector array are positioned so that they are optically coupled to one another by the optical substrate to process the reflected light.

Claims

1. A MEMS spectrometer, comprising:

an optical substrate having a first planar face and a second planar face parallel throughout to said first planar face;

a first semiconductor comprising substrate attached to said first planar face having a slit for passing incident light to said optical substrate, and at least one integrated reflective grating, and at least one integrated detector array, and

a second semiconductor comprising substrate attached to said second planar face, including at least a first integrated mirror and a second integrated mirror thereon,

wherein said first integrated mirror is positioned to receive said incident light transmitted by said optical substrate and provide reflected light, and said integrated reflective grating, said second integrated mirror and said integrated detector array are positioned so that they are optically coupled to one another by said optical substrate to process said reflected light.

2. The MEMS spectrometer of claim 1,

wherein said integrated reflective grating and said integrated detector array of said first substrate are both positioned on a first common side of said first substrate and said first common side is attached to face inward to said planar first face, and said first integrated mirror and said second integrated mirror are both positioned on a second common side of said second substrate and said second common side is attached to face inward to said planar second face.

3. The MEMS spectrometer of claim 1, wherein said integrated reflective grating comprises a blazed grating.

4. The MEMS spectrometer of claim 1, wherein said first semiconductor comprising substrate is attached by a first optical adhesive to said first planar face and said second semiconductor comprising substrate is attached by a second optical adhesive to said second planar face.

5. The MEMS spectrometer of claim 1, wherein said optical substrate comprises fused silica, CaF₂, ZnSe, sapphire, MgF₂ or BaF₂.

6. The MEMS spectrometer of claim 1, wherein said first and said second substrate comprise silicon.

7. The MEMS spectrometer of claim 1, wherein said first integrated mirror and said second integrated mirror both comprise focusing mirrors.

8. The MEMS spectrometer of claim 1, wherein said first and said second substrate comprise silicon and said integrated detector array comprises a photodiode array, an avalanche diode array or a phototransistor array.

9. A sensing system, comprising:

a probe including a light source and sample collection area that receives light from said light source for sensing a presence of at least one target when received in said sample collection area, said sample collection area emitting a detection signal responsive to said receiving said light, and

a MEMS spectrometer for receiving and processing said detection signal, wherein said MEMS spectrometer comprises;

an optical substrate having a first planar face and a second planar face parallel throughout to said first planar face;

a first semiconductor comprising substrate attached to said first planar face having a slit for passing said detection signal to said optical substrate, at least one integrated reflective grating, and at least one integrated detector array formed, and

a second semiconductor comprising substrate attached to said second planar face including at least a first integrated mirror and a second integrated mirror,

wherein said first integrated mirror is positioned to receive said detection signal transmitted by said optical substrate and provide a reflected detection signal, and said integrated reflective grating, said second integrated mirror and said integrated detector array are positioned so that they are optically coupled to one another by said optical substrate to process said reflected detection signal.

10. The sensing system of claim 9, wherein said integrated reflective grating and said integrated detector array of said first substrate are both positioned on a first common side of said first substrate and said first common side is attached to face inward to said first planar face, and said first integrated mirror and said second integrated mirror are both positioned on a second common side of said second substrate and said second common side is attached to face inward to said second planar face.

11. The sensing system of claim 9, wherein said integrated reflective grating comprises a blazed grating.

12. The sensing system of claim 9, wherein said first semiconductor comprising substrate is attached by a first optical adhesive to said first planar face and said second semiconductor comprising substrate is attached by a second optical adhesive to said second planar face.

13. The sensing system of claim 9, wherein said optical substrate comprises fused silica, CaF₂, ZnSe, Al₂O₃, MgF₂ or BaF₂.

14. The sensing system of claim 9, wherein said first and said second substrate comprise silicon.

15. The sensing system of claim 9, wherein said first integrated mirror and said second integrated mirror comprise focusing mirrors.

16. The sensing system of claim 9, wherein said first and said second substrate comprise silicon and said integrated detector array comprises a photodiode array, an avalanche diode array or a phototransistor array.

17. The sensing system of claim 9, wherein said probe comprises a SERS probe chip comprising a SERS substrate.