University of Michigan

Xiaogan Liang

Katsuo Kurabayashi

Byunghoon Ryu

Hongsuk Nam

Sungjin Wi

Mikai Chen

Young Geun Park

Provided herein are systems and methods for performing assays. In particular, provided herein are systems and methods for performing sensitive and rapid immunoassays.

Plasmo photoelectronic immunosensor

The superior electronic and mechanical properties of 2D-layered transition metal dichalcogenides and other 2D layered materials could be exploited to make a broad range of devices with attractive functionalities. However, the nanofabrication of such layered-material-based devices still needs resist-based lithography and plasma etching processes for patterning layered materials into functional device features. Such patterning processes lead to unavoidable contaminations, to which the transport characteristics of atomically-thin layered materials are very sensitive. More seriously, such lithography-introduced contaminants cannot be safely eliminated by conventional material wafer cleaning approaches. This disclosure introduces a rubbing-induced site-selective growth method capable of directly generating few-layer molybdenum disulfide device patterns without the need of any additional patterning processes. This method consists of two critical steps: (i) a damage-free mechanical rubbing process for generating microscale triboelectric charge patterns on a dielectric surface, and (ii) site-selective deposition of molybdenum disulfide or the like within rubbing-induced charge patterns.

Rubbing-induced site-selective growth of device patterns

A method for generating a non-volatile memory device may comprise: applying plasma for a preset time period to an exposed surface of a channel of a field effect transistor such that a plurality of charge-trapping sites are formed at the channel. The channel is comprised of a multi-layer structure of atomically thin two-dimensional sheets.

Field effect transistor memory device

Atomically layered transition metal dichalcogenides (TMDCs) exhibit a significant potential to enable low-cost transistor biosensors that permit single-molecule-level quantification of biomolecules. Two different principles for operating such biosensors are presented. In one arrangement, antibody receptors are functionalized on an insulating layer deposited onto the channel of the transistor. The charge introduced through antigen-antibody binding is capacitively coupled with the channel and shifts the threshold voltage without significantly changing the transconductance. In another arrangement, antibodies are functionalized directly on the channel of the transistor. Antigen-antibody binding events mainly modulate the ON-state transconductance, which is attributed to the disordered potential formed in channel material.

Two-dimensional material-based field-effect transistor sensors

Plasma-assisted techniques are provided for fabricating semiconductor devices. In one aspect, a plasma is applied to a substrate before exfoliating layers of a multi-layer structure of atomically thin two-dimensional sheets onto the substrate. The exfoliated layers serve as the basis for constructing a semiconductor device. In another aspect, a p-n junction is formed by applying a plasma to top layers of a multi-layer structure of atomically thin two-dimensional sheets and then exfoliating a portion of the multi-layer structure onto a bottom electrode.

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Ann Arbor, MI, United States of America

Xiaogan Liang