LOW NOISE CHEMICALLY-SENSITIVE FIELD EFFECT TRANSISTORS

• US 20120286333A1
• Filed: 07/20/2012
• Published: 11/15/2012
• Est. Priority Date: 12/14/2006
• Status: Active Grant

• Current Assignee: Life Technologies Corporation (Thermo Fisher Scientific Incorporated)
• Original Assignee: Life Technologies Corporation (Thermo Fisher Scientific Incorporated)
• Inventors: Rothberg, Jonathan M., Hinz, Wolfgang, Johnson, Kim L., Bustillo, James
• Granted Patent: US 8,445,945 B2
• Time in Patent Office: Days
• US Class Current: 257/253
• CPC Class Codes: C12Q 1/6818 involving interaction of two or more labels, e.g. resonant energy transfer
• CPC Class Codes: C12Q 1/6874 involving nucleic acid arrays, e.g. sequencing by hybridisation
• CPC Class Codes: C12Q 2533/101 Primer extension
• CPC Class Codes: C12Q 2565/301 Pyrophosphate (PPi)
• CPC Class Codes: C12Q 2565/607 being a sensor, e.g. electrode
• CPC Class Codes: G01N 27/4145 specially adapted for biomolecules, e.g. gate electrode with immobilised receptors
• CPC Class Codes: G01N 27/4148 Integrated circuits therefor, e.g. fabricated by CMOS processing CMOS processing per se H01L21/82
• CPC Class Codes: G01N 33/54373 involving physiochemical end-point determination, e.g. wave-guides, FETS, gratings
• CPC Class Codes: G01N 33/5438 Electrodes
• CPC Class Codes: H01L 27/088 the components being field-effect transistors with insulated gate
• CPC Class Codes: H01L 29/42324 Gate electrodes for transistors with a floating gate
• CPC Class Codes: H01L 29/78 with field effect produced by an insulated gate H01L29/7725, H01L29/775, H01L29/778 take precedence
• CPC Class Codes: H01L 2924/01006 Carbon [C]
• CPC Class Codes: H01L 2924/01013 Aluminum [Al]
• CPC Class Codes: H01L 2924/01015 Phosphorus [P]
• CPC Class Codes: H01L 2924/01073 Tantalum [Ta]
• CPC Class Codes: H01L 2924/14 Integrated circuits
• CPC Class Codes: H01L 2924/1433 Application-specific integrated circuit [ASIC]
• CPC Class Codes: Y10T 436/22 Hydrogen, per se

Abstract

Methods and apparatus relating to very large scale FET arrays for analyte measurements. ChemFET (e.g., ISFET) arrays may be fabricated using conventional CMOS processing techniques based on improved FET pixel and array designs that increase measurement sensitivity and accuracy, and at the same time facilitate significantly small pixel sizes and dense arrays. Improved array control techniques provide for rapid data acquisition from large and dense arrays. Such arrays may be employed to detect a presence and/or concentration changes of various analyte types in a wide variety of chemical and/or biological processes. In one example, chemFET arrays facilitate DNA sequencing techniques based on monitoring changes in hydrogen ion concentration (pH), changes in other analyte concentration, and/or binding events associated with chemical processes relating to DNA synthesis.

Claims

1. A chemically-sensitive field effect transistor (chemFET), comprising:

a substrate including a doped semiconductor region;

a gate dielectric on the region;

a floating gate structure, comprising;

a gate element on the gate dielectric;

a first conductive element and a sensor plate in a first conductor layer overlying the gate element, wherein the first conductive element is electrically coupled to the gate element by an interlayer connector, and the sensor plate is separated from the first conductive element by an interlayer dielectric;

a jumper element in a second conductor layer overlying the first conductor layer, the jumper element electrically connecting the sensor plate to the first conductive element; and

a passivation layer over the sensor plate.

2. The chemFET of claim 1, wherein the floating gate structure further comprises a second conductive element in a third conductor layer between the gate element and the first conductive element, the first conductive element connected to the gate element and the first conductive element by interlayer connectors.

3. The chemFET of claim 2, further comprising a source and a drain in the semiconductor substrate, and wherein the third conductor layer further includes access lines coupled to the source and the drain.

4. The chemFET of claim 1, wherein the passivation layer comprises a portion of an interlayer dielectric between the jumper element and the sensor plate.

5. The chemFET of claim 1, wherein the first conductive element is in a vertical column overlying the gate element.

6. The chemFET of claim 1, further comprising a chemical sample well overlying the sensor plate, the passivation layer within the chemical sample well.

7. The chemFET of claim 6, wherein the passivation layer is formed on at least a bottom surface of the chemical sample well.

8. The chemFET of claim 6, wherein the chemical sample well is configured to hold an analyte solution in contact with the passivation layer.

9. The chemFET of claim 1, wherein the passivation layer is a metal-oxide.

10. The chemFET of claim 1, wherein the passivation layer is sensitive to hydrogen ions.

11. The chemFET of claim 1, wherein the jumper element is coupled to the jumper element and the first conductive element by interlayer connectors.