Heterojunction nanopore for sequencing
A technique is provided for performing sequencing with a nanodevice. Alternating graphene layers and dielectric layers are provided one on top of another to form a multilayer stack of heterojunctions. The dielectric layers include boron nitride, molybdenum disulfide, and/or hafnium disulfide layers. A nanopore is formed through the graphene layers and the dielectric layers. The graphene layers are individually addressed by applying individual voltages to each of the graphene layers on a one to one basis when a particular base of a molecule is in the nanopore. Each of the graphene layers is an electrode. Individual electrical currents are measured for each of the graphene layers as the particular base moves from a first graphene layer through a last graphene layer in the nanopore. The base is identified according to the individual electrical currents repeatedly measured for the base moving from the first through last graphene layer in the nanopore.
1. A method of performing sequencing with a nanodevice, the method comprising: providing alternating graphene layers and dielectric layers one on top of another to form a multilayer stack of heterojunctions, wherein the dielectric layers include at least one of boron nitride layers, molybdenum disulfide layers, and hafnium disulfide layers;
forming a nanopore through each of the graphene layers and the dielectric wherein the nanopore is configured to accept a molecule for sequencing;
individually addressing each of the graphene layers by applying individual voltages to each of the graphene layers on a one to one basis when a particular base of is in the nanopore, wherein each of the graphene layers is an electrode such that the graphene layers include a first graphene layer, a second graphene layer, and a third graphene layer;
respectively measuring individual electrical currents for each of the graphene layers as the particular base moves from graphene layer, to the second graphene layer, through the third graphene layer in the nanopore; and
determining an identification of the particular base according to the individual electrical currents repeatedly measured for the particular base moving from the first graphene layer, to the second graphene layer, through the third graphene layer in the nanopore;
wherein the first graphene layer is connected to a first pair of electrodes for a first measurement, the second graphene layer is connected to a second pair of electrodes for a second measurement, and the third graphene layer is connected to a third pair of electrodes for a third measurement.
2. The method of claim 1 , wherein determining the identification of the particular base according to the individual electrical currents repeatedly measured for the particular base is based on measured values of the individual electrical currents being the same or nearly the same.
3. The method of claim 1 , wherein the individual electrical currents each correspond to the particular base at different locations in the nanopore.
4. The method of claim 1 , wherein the individual electrical currents correspond to measuring via the graphene layers as the electrodes on a one to one basis, such that no graphene layer measures the particular base more than once.
5. The method of claim 1 , wherein a number of the individual electrical currents measured for the particular base at different locations in the nanopore equals a number of the graphene layers.
6. The method of claim 1 , wherein the dielectric layers include a combination of the boron nitride layers, the molybdenum disulfide layers, and the hafnium disulfide layers.
7. The method of claim 1 , wherein the boron nitride layers each have one or few mono-layers of boron nitride; and
wherein each mono-layer of the boron nitride has a thickness of 0.3 nanometers to 0.5 nanometers.
8. The method of claim 1 , wherein the molybdenum disulfide layers each have one or few mono-layers of molybdenum disulfide; and
wherein each mono-layer of the molybdenum disulfide has a thickness of 0.6 nanometers to 0.8 nanometers.
9. The method of claim 1 , wherein a size of the nanopore ranges from 0.5 nanometers to 100 nanometers.
10. The method of claim 1 , wherein the graphene layers each have a narrowed graphene strip corresponding to a location of the nanopore; and
wherein a width of the narrowed graphene strip is in a range of 1 to 200 nanometers.
11. A method of forming a nanodevice for sequencing, the method comprising:
disposing alternating graphene layers and dielectric layers one on top of another to form a multilayer stack of heterojunctions, wherein a first graphene layer of the graphene layers is initially disposed on an insulator that is disposed on a substrate, and wherein the dielectric layers include at least one of boron nitride layers, molybdenum disulfide layers, and hafnium disulfide layers;
drilling a nanopore through each of the graphene layers and the dielectric layers, wherein the graphene layers include the first graphene layer, a second graphene layer, and a third graphene layer; and
disposing pairs of metal electrodes onto the graphene layers at opposing ends, such that the first graphene layer is connected to a first pair of metal electrodes for a first measurement, the second graphene layer is connected to a second pair of metal electrodes for a second measurement, and the third graphene layer is connected to a third pair of metal electrodes for a third measurement.
12. The method of claim 11 , wherein the boron nitride layers each have one or few mono-layers of boron nitride; and
wherein each mono-layer of the boron nitride has a thickness of 0.3 nanometers to 0.5 nanometers when disposed.
13. The method of claim 11 , wherein the molybdenum disulfide layers each have one or few mono-layers of molybdenum disulfide; and
wherein each mono-layer of the molybdenum disulfide has a thickness of 0.6 nanometers to 0.8 nanometers when disposed.