Embedded noble metal electrodes in microfluidics

• US 10,247,700 B2
• Filed: 10/30/2015
• Issued: 04/02/2019
• Est. Priority Date: 10/30/2015
• Status: Active Grant

• Current Assignee: BioNano Genomics, Inc., International Business Machines Corporation
• Original Assignee: BioNano Genomics, Inc., International Business Machines Corporation
• Inventors: Hu, Huan, Lofaro, Michael F., Smith, Joshua T., Wunsch, Benjamin H., Solis, Daniel J.
• Primary Examiner(s): Ball, J. Christopher
• Application Number:
  US14/928,596
• Publication Number:
  US 20170122903A1
• Time in Patent Office: 1,250 Days
• CPC Class Codes: B01L 2200/10 Integrating sample preparation and analysis in single entity, e.g. lab-on-a-chip concept
• CPC Class Codes: B01L 2200/12 Specific details about manufacturing devices
• CPC Class Codes: B01L 2300/0896 Nanoscaled
• CPC Class Codes: B01L 2400/0421 electrophoretic flow
• CPC Class Codes: B01L 3/502707 characterised by the manufacture of the container or its components by shaping or joining plastic parts B29C59/00, B29C65/00; by laminating B32B37/00; manufacture of microstructural devices in general B81C
• CPC Class Codes: G01N 27/44791 Microapparatus sample containers with integrated microfluidic structures B01L3/5027

Abstract

A technique relates to manufacturing a nanogap. An oxide layer is disposed on top of a substrate. A release layer is disposed in a pattern on top of the oxide layer. A patterned trench is etched into the oxide layer using the pattern of the release layer. A metal layer is disposed on the release layer and in the patterned trench. A polish removes the release layer, thereby removing both the release layer and a portion of the metal layer having been disposed on top of the release layer, such that the metal layer remaining includes a first metal part and a second metal part connected by a metal nanowire. The metal layer remaining is coplanar with the oxide layer. A nanochannel is formed in the oxide layer in a region of the metal nanowire. The nanogap is formed in the metal nanowire separating the first and second metal parts.

Claims

1. A structure formed with a nanogap, the structure comprising:

an oxide layer formed on top of a substrate;

a patterned trench formed into the oxide layer according to a pattern of a sacrificial release layer to be removed;

a metal layer formed in the patterned trench of the oxide layer and on a surface of the oxide layer, wherein the metal layer is coplanar with the oxide layer, and wherein the metal layer in the patterned trench comprises a first metal part formed in the oxide layer and on the surface of the oxide layer, a second metal part formed in the oxide layer and on the surface of the oxide layer, and a metal nanowire between the first and second metal parts; and

the nanogap formed in the metal nanowire, such that the first metal part and the second metal part are separated by the nanogap; and

a nanochannel formed in the oxide layer in a region of the nanogap, the nanogap being parallel to the nanochannel and perpendicular to the metal nanowire;

wherein the nanogap, the first metal part, the second metal part, and the nanochannel lie in a same plane;

wherein a width dimension of the first metal part and second metal part is greater than a width dimension of the metal nanowire.

2. The structure of claim 1, further comprising a cover over at least the nanochannel, the nanogap, and the first and second metal parts.

3. The structure of claim 1, wherein the metal layer in the patterned trench is free from scratches.

4. The structure of claim 1, wherein the metal layer is a noble metal.

5. The structure of claim 1, wherein the metal layer comprises at least one of palladium, platinum, and gold.

6. The structure of claim 1, wherein the substrate comprises silicon.

7. The structure of claim 1, wherein the oxide layer is silicon dioxide.

8. The structure of claim 1, wherein the metal layer is embedded in the oxide layer such that a top metal surface of the metal layer is coplanar with a top oxide surface of the oxide layer.

9. The structure of claim 1, wherein the nanochannel interfaces with the metal nanowire at the nanogap.