Graphene transistors on microbial cellulose

Patent metadata

Field	Value
Publication number	US-10559694-B1
Application number	US-201715590298-A
Country	US
Kind code	B1
Filing date	May 9, 2017
Priority date	Feb 19, 2015
Publication date	Feb 11, 2020
Grant date	Feb 11, 2020

Abstract

A device including a biopolymer membrane, a passivation layer on the biopolymer membrane, a graphene layer on the passivation layer, a source electrode on the graphene layer, and a drain electrode on the graphene layer, wherein the graphene layer extends between the source electrode and the drain electrode.

First claim

What is claimed is:

1. A method of making a device comprising:
transferring a biopolymer membrane onto a handling wafer;
forming a passivation layer on the biopolymer membrane;
transferring graphene onto the passivation layer;
patterning the graphene to form at least one graphene mesa;
forming a source contact on the graphene mesa;
forming a drain contact on the graphene mesa;
etching the passivation layer surrounding the graphene mesa, the source contact, and the drain contact to expose the biopolymer membrane; and
releasing the biopolymer membrane from the handling wafer.

2. The method of claim 1 further comprising:
drying the biopolymer membrane after transferring the biopolymer membrane onto the handling wafer.

3. The method of claim 1 further comprising:
forming a gate insulator on the graphene mesa; and
forming a gate electrode on the gate insulator;
wherein the gate electrode is between the source contact and the drain contact.

4. The method of claim 1 wherein the biopolymer membrane comprises microbial cellulose.

5. The method of claim 1 wherein the passivation layer comprises a dielectric.

6. The method of claim 1 wherein the passivation layer comprises:
a dielectric on the biopolymer membrane; and
a bio-compatible polymer on the dielectric.

7. The method of claim 6 :
wherein the dielectric comprises Al 2 O 3 , SiO 2 , or HfO 2 ; and
wherein the bio-compatible polymer comprises SU-8, polyimide, parylene, or polydimethylsiloxane (PDMS).

8. The method of claim 1 wherein the passivation layer comprises a bio-compatible polymer on the biopolymer membrane.

9. The method of claim 1 wherein the graphene comprises a chemical vapor deposition-grown graphene.

10. The method of claim 1 wherein the handling wafer comprises Si, Ge, InP, GaAs, SiO 2 , sapphire, quartz, or glass.

11. The method of claim 1 :
wherein the biopolymer membrane has a thickness of less than 10 μm; and
wherein the passivation layer comprises an atomic layer deposition of dielectric having a thickness of less than 10 nm, or wherein the passivation layer comprises a bio-compatible polymer having a thickness of about 1 μm.

12. The method of claim 1 :
wherein the biopolymer membrane is compatible with in vivo sensors and electronics.

Assignees

• Hrl Lab Llc

Inventors

• Son Kyung-Ah
• Yang Baohua
• Seo Hwa Chang
• Wong Danny
• Moon Jeong-Sun

Classifications

• G01N27/414

  Ion-sensitive or chemical field-effect transistors, i.e. ISFETS or CHEMFETS · CPC title

• H01L29/78684 Primary

  Electricity · mapped topic

• H01L29/1606

  Electricity · mapped topic

• H01L29/66742

  Electricity · mapped topic

• H10D30/6757

  characterised by the structure of the channel, e.g. transverse or longitudinal shape or doping profile (TFTs having channel structures for preventing kink or snapback effects H10D30/6708; TFTs having lightly-doped source or drain extensions H10D30/6715) · CPC title