Biosensor capacitor

• US 8,986,523 B2
• Filed: 01/19/2012
• Issued: 03/24/2015
• Est. Priority Date: 01/19/2012
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Ackerson, Kristin M., Ellis-Monaghan, John J., Gambino, Jeffrey P., Lim, Yen Li, Razina, Polina A.
• Primary Examiner(s): NOGUEROLA, ALEXANDER STEPHAN
• Application Number:
  US13/353,523
• Publication Number:
  US 20130186754A1
• Time in Patent Office: 1,160 Days
• US Class Current: 204/403.01
• CPC Class Codes: G01N 27/22 by investigating capacitance
• CPC Class Codes: G01N 27/3276 being a hybridisation with immobilised receptors using a FET type sensor G01N27/4145; concerning the hybridisation C12Q1/68
• CPC Class Codes: H01L 2224/02166 Collar structures
• CPC Class Codes: H01L 2224/036 by patterning a pre-deposited material treatment of parts prior to assembly of the devices H01L21/48
• CPC Class Codes: H01L 2224/0401 Bonding areas specifically adapted for bump connectors, e.g. under bump metallisation [UBM]
• CPC Class Codes: H01L 2224/04042 Bonding areas specifically adapted for wire connectors, e.g. wirebond pads
• CPC Class Codes: H01L 2224/05157 Cobalt [Co] as principal constituent
• CPC Class Codes: H01L 2224/0518 Molybdenum [Mo] as principal constituent
• CPC Class Codes: H01L 2224/05181 Tantalum [Ta] as principal constituent
• CPC Class Codes: H01L 2224/05184 Tungsten [W] as principal constituent
• CPC Class Codes: H01L 2224/05186 with a principal constituent of the material being a non metallic, non metalloid inorganic material
• CPC Class Codes: H01L 2224/05624 Aluminium [Al] as principal constituent
• CPC Class Codes: H01L 2224/13101 the principal constituent melting at a temperature of less than 400°C
• CPC Class Codes: H01L 2224/45144 Gold (Au) as principal constituent
• CPC Class Codes: H01L 2224/45147 Copper (Cu) as principal constituent
• CPC Class Codes: H01L 2224/4847 the connecting portion on the bonding area of the semiconductor or solid-state body being a wedge bond
• CPC Class Codes: H01L 2224/48624 Aluminium (Al) as principal constituent
• CPC Class Codes: H01L 2224/48824 Aluminium (Al) as principal constituent
• CPC Class Codes: H01L 23/5223 Capacitor integral with wiring layers
• CPC Class Codes: H01L 24/03 Manufacturing methods
• CPC Class Codes: H01L 24/05 : of an individual bonding area
• CPC Class Codes: H01L 24/13 : of an individual bump connector
• CPC Class Codes: H01L 24/45 : of an individual wire connector
• CPC Class Codes: H01L 24/48 : of an individual wire connector
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/00014 : the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/12042 : LASER
• CPC Class Codes: H01L 2924/1306 : Field-effect transistor [FET]

Abstract

A biosensor capacitor, including a dielectric layer; a first metal layer in the dielectric layer; a passivation layer over the dielectric layer and the first metal layer; an isolation layer over the passivation layer; a probe DNA electrode connected to the first metal layer; a counter electrode connected to the first metal layer wherein the counter electrode forms an enclosure around the probe DNA electrode; and a bond pad connected to the first metal layer.

Claims

1. A biosensor capacitor, comprising:

a dielectric layer;

a first metal layer in the dielectric layer;

a first diffusion barrier including a refractory metal over the first metal layer;

a passivation layer over the dielectric layer and the first metal layer;

an isolation layer over the passivation layer;

a probe DNA electrode connected to the first metal layer;

a counter electrode connected to the first metal layer wherein the counter electrode forms an enclosure around the probe DNA electrode; and

a bond pad connected to the first metal layer.

2. The biosensor capacitor of claim 1, wherein the probe DNA electrode includes a second metal layer and the counter electrode and the bond pad include aluminum, and wherein the second metal layer comprises one of gold, platinum, palladium, nickel, chromium, platinum palladium alloy, and nickel chromium alloy.

3. The biosensor capacitor of claim 1, wherein the probe DNA electrode and the counter electrode include a second metal layer and the bond pad includes aluminum, and wherein the second metal layer comprises one of gold, platinum, palladium, nickel, chromium, platinum palladium alloy, and nickel chromium alloy.

4. The biosensor capacitor of claim 1, wherein the probe DNA electrode includes a second metal layer and the counter electrode and the bond pad include copper, and wherein the second metal layer comprises one of gold, platinum, palladium, nickel, chromium, platinum palladium alloy, and nickel chromium alloy.

5. The biosensor capacitor of claim 4, further comprising:

a second diffusion barrier including a refractory metal over the counter electrode; and

a third metal layer over the second diffusion barrier, wherein the third metal layer comprises one of gold, platinum, palladium, nickel, chromium, platinum palladium alloy, and nickel chromium alloy.

6. The biosensor capacitor of claim 1, further comprising:

a wire bond or solder ball connection to the bond pad.

7. A method, comprising:

forming a bond pad via, a counter electrode via, and a probe DNA electrode via through an isolation layer and a passivation layer to a first metal layer in a dielectric layer;

forming a first diffusion barrier in each via over the first metal layer;

forming a probe DNA electrode by forming a second metal layer over the first diffusion barrier in the probe DNA electrode via;

forming a counter electrode in the counter electrode via, wherein the counter electrode forms an enclosure around the probe DNA electrode via; and

forming a bond pad in the bond pad via.

8. The method of claim 7, wherein the first diffusion barrier comprises cobalt-tungsten-phosphide, tantalum, tantalum nitride, molybdenum, and nickel or alloys thereof.

9. The method of claim 7, wherein the second metal layer comprises one of gold, platinum, palladium, nickel, chromium, platinum palladium alloy, and nickel chromium alloy and the counter electrode and the bond pad include aluminum.

10. The method of claim 7, wherein the second metal layer comprises one of gold, platinum, palladium, nickel, chromium, platinum palladium alloy, and nickel chromium alloy and the counter electrode includes gold and the bond pad includes aluminum.

11. The method of claim 7, wherein the second metal layer comprises one of gold, platinum, palladium, nickel, chromium, platinum palladium alloy, and nickel chromium alloy and the counter electrode and the bond pad include copper.

12. The method of claim 11, further comprising:

forming a second diffusion barrier over the counter electrode; and

forming a third metal layer over the second diffusion barrier, wherein the third metal layer one of gold, platinum, palladium, nickel, chromium, platinum palladium alloy, and nickel chromium alloy.

13. The method of claim 7, further comprising:

forming a wire bond or a solder ball connection to the bond pad.

14. A biosensor capacitor, comprising:

a dielectric layer;

a first metal layer in the dielectric layer;

a passivation layer over the dielectric layer and the first metal layer;

an isolation layer over the passivation layer

a probe DNA electrode including copper connected to the first metal layer;

a counter electrode including copper connected to the first metal layer;

a first diffusion barrier including a refractory metal over the counter electrode and the probe DNA electrode;

a second metal layer over the first diffusion barrier; and

a bond pad including copper connected to the first metal layer.

15. The biosensor capacitor of claim 14, wherein the first diffusion barrier comprises cobalt-tungsten-phosphide, tantalum, tantalum nitride, molybdenum, and nickel or alloys thereof.

16. The biosensor capacitor of claim 14, further comprising:

a diffusion barrier including a refractory metal over the counter electrode, the probe DNA electrode, and the bond pad; and

a third metal layer over the diffusion barrier.

17. The biosensor capacitor of claim 16, wherein the diffusion barrier comprises cobalttungsten-phosphide, tantalum, tantalum nitride, molybdenum, and nickel or alloys thereof.

18. The biosensor capacitor of claim 14, further comprising:

a wire bond or solder ball connection to the bond pad.