Biosensor chip sensor protection methods

• US 8,536,661 B1
• Filed: 06/27/2005
• Issued: 09/17/2013
• Est. Priority Date: 06/25/2004
• Status: Active Grant

• Current Assignee: University of Hawai'i
• Original Assignee: University of Hawai'i
• Inventors: Holm-Kennedy, James W.
• Primary Examiner(s): Nguyen, Ha Tran T
• Assistant Examiner(s): QUINTO, KEVIN V
• Application Number:
  US11/167,913
• Time in Patent Office: 3,004 Days
• Field of Search: 257/414, 257/253, 438/48, 438/49
• US Class Current: 257/414
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: B82Y 15/00 Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors
• CPC Class Codes: C12Q 1/686 Polymerase chain reaction [PCR]
• CPC Class Codes: G01N 27/4145 specially adapted for biomolecules, e.g. gate electrode with immobilised receptors
• CPC Class Codes: H01L 29/0665 the shape of the body defining a nanostructure nanotechnology per se B82B
• CPC Class Codes: H01L 29/0673 oriented parallel to a substrate
• CPC Class Codes: H01L 29/4908 for thin film semiconductor, e.g. gate of TFT
• CPC Class Codes: H01L 29/66439 with a one- or zero-dimensional channel, e.g. quantum wire FET, in-plane gate transistor [IPG], single electron transistor [SET], striped channel transistor, Coulomb blockade transistor with an active layer made of a group 13/15 material H01L29/66469

Abstract

Receptors are selectively attached by introducing blocking materials in the areas outside the active sensor surface area, and/or selectively attaching the bio receptors to one or more active sensor surface areas. Methods for selective attachment include the use of optical attachment using a patterned exposure to assist in the creation of receptor bonding to pre-selected regions of the one or more chips. Blocking agents are attached to regions where blocking the receptor attachment is beneficial. Biased conducting regions may also affect selective attachment. Such controlled blocking may be accomplished using optical patterning exposure with optical assisted bonding of the blocking molecule or lift off processes. Patterned exposure for either attachment assists or liftoff processes employs photo masks. Conducting regions outside of the active sensor gate region are biased, affecting biochemical binding or non binding, and shielding of the semiconductor region outside of the active biosensor region.

Claims

1. A sensing apparatus comprising a sensor comprising:

a substrate,

a sensing area in or on the substrate,

a protective region on the substrate located outside the sensing area and at least one selected from a group consisting of

a conductor region on the protective region outside the sensing area, and

a repellant blocking region on the sensor outside the sensing area, wherein the conductor region is not electrically connected to a sensor source or drain.

2. The apparatus of 1, wherein the conductor region is biased to protect the region surrounding the active sensor area from undesirable chemical attachment.

3. The apparatus of claim 1, wherein the conductor region comprises a surface protection bias.

4. The apparatus of claim 1, wherein the substrate comprises a sensor back gate bias.

5. The apparatus of claim 1, wherein the protective region comprises an insulator region around the conductor region.

6. The apparatus of claim 1, wherein the repellant blocking region comprises a biochemical repellant blocking region.

7. The apparatus of claim 1, wherein the repellant blocking region comprises an inert coating blocking region.

8. The apparatus of claim 1, wherein the repellant blocking region comprises a conductive shielding blocking region.

9. The apparatus of claim 1, further comprising a source coupled to the sensor.

10. The apparatus of claim 1, wherein the sensing area comprises a sensing region, a gate region on the sensing region, and an attachment region on the gate region for receiving and attaching material to be sensed.

11. The apparatus of claim 10, wherein the attachment region comprises receptors on the gate region for receiving and attaching targeted materials to only the sensing area.

12. The apparatus of claim 10, further comprising a light source, wherein the gate region is exposed to light from the light source for bonding pre-selected chemicals to the gate region.

13. The apparatus of claim 1, wherein the sensing area comprises a sensing region, at least one selected from a group consisting of an insulator, a conductor or a semiconductor on the sensing region, a gate region on the conductor, semiconductor or the insulator, and receptors on the gate region for receiving and attaching the targeted materials to only the sensing area.

14. The apparatus of claim 13, wherein the targeted materials comprise targeted biochemicals.

15. The apparatus of claim 14, wherein the receptors comprise a chemical attachment layer on the gate region for selective attachment of the targeted biochemicals.

16. The apparatus of claim 15, further comprising a light source for exposing the gate to light from the light source for binding of biochemicals where said biochemicals are at least one selected from a group consisting of

receptor elements,

targeted biochemicals, and

blocking chemicals.

17. The apparatus of claim 1, wherein the repellant blocking region comprises a photo mask covering the protective region thereby isolating exposure of the materials to only the sensing area.

18. The apparatus of claim 17, wherein the photo mask is an opaque mask for masking the sensor except for the receptors to allow light from a light source to fall only on the sensing area.

19. A sensing apparatus comprising a sensor comprising:

a substrate,

a sensing area in or on the substrate,

a protective region on the substrate located outside the sensing area and at least one selected from a group consisting of

a conductor region on the protective region outside the sensing area, and

a repellant blocking region on the sensor outside the sensing area, wherein the repellant blocking region is a chemical attachment region.

20. The apparatus of claim 19, wherein the protective region or the repellant blocking region is a biochemical region.

21. The apparatus of claim 19, wherein the protective region or the repellant blocking region is an inert coating region.

22. The apparatus of claim 19, wherein the protective region or the repellant blocking region is a conductive shielding region.

23. The apparatus of claim 19, wherein the repellant blocking region prevents sensor degradation by biochemical influences.

24. The apparatus of claim 19, further comprising a source coupled to the sensing area.

25. The apparatus of claim 19, further comprising a drain coupled to the sensing area.

26. The apparatus of claim 19, wherein the repellant blocking region comprises a photo mask covering the protective region thereby isolating ambient exposure to only the sensing area.

27. The apparatus of claim 26, wherein the photo mask is an opaque mask for masking the sensor except and selectively allowing light from a light source to fall only on the sensor'"'"'s sensing area.

28. A sensing method using the apparatus of claim 19, the method comprising providing a sensor including:

providing a substrate in the sensor,

providing a sensing area in or on the substrate,

attracting target material to be sensed,

attaching the target material to the sensing area,

providing a protective region on the substrate,

isolating the sensing area from substrate areas outside the sensing area with the protective region,

providing a repellant blocking region on the substrate outside the sensor surface,

preventing the target material and other biochemicals from attaching to the other areas outside of the sensor surface with the repellant blocking region,

enabling attachment of the target material to only the sensing area, and

sensing the attached target material.