Surface engineering for enhancement of sensitivity in an underlap-FET biosensor by control of wettability.

Biosens Bioelectron

Department of Electrical Engineering, KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Republic of Korea.

Published: March 2013

The present work aims to improve the sensitivity of an electrical biosensor by simply changing a surface property of the passivation layer, which covers the background region except for the sensing site for electrical isolation among adjacent interconnection lines. The hydrophobic passivation layer dramatically enhances the sensitivity of the biosensor when compared with a hydrophilic passivation layer. A revamped metal oxide semiconductor field-effect transistor (MOSFET), which has a designed underlap region between a gate and a drain, is used as the electrical biosensor. A thin film of CYTOP(TM) and silicon nitride is used as the hydrophobic and hydrophilic passivation layers, respectively. The surface antigen and its specific antibody of the avian influenza virus were employed as the probe and target biomolecule, respectively, to confirm the enhanced sensitivity of the proposed biosensor. By using hydrophobic passivation, the limit of detection of the biosensor was improved up to 100-fold compared with that resulting from hydrophilic passivation. Therefore, a simple surface engineering to control surface wettability can notably improve the sensitivity of a biosensor without additional efforts, such as modifying the sensor structure, optimizing the bio-treatment protocol, or increasing the binding yield between a probe and its target, among other efforts.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bios.2012.08.036DOI Listing

Publication Analysis

Top Keywords

passivation layer
12
hydrophilic passivation
12
surface engineering
8
improve sensitivity
8
electrical biosensor
8
hydrophobic passivation
8
sensitivity biosensor
8
compared hydrophilic
8
probe target
8
biosensor
7

Similar Publications

The tunability of the energy bandgap in the near-infrared (NIR) range uniquely positions colloidal lead sulfide (PbS) quantum dots (QDs) as a versatile material to enhance the performance of existing perovskite and silicon solar cells in tandem architectures. The desired narrow bandgap (NBG) PbS QDs exhibit polar (111) and nonpolar (100) terminal facets, making effective surface passivation through ligand engineering highly challenging. Despite recent breakthroughs in surface ligand engineering, NBG PbS QDs suffer from uncontrolled agglomeration in solid films, leading to increased energy disorder and trap formation.

View Article and Find Full Text PDF

Gradient Surface Gallium-Doped Hematite Photoelectrode for Enhanced Photoelectrochemical Water Oxidation.

Nano Lett

January 2025

Institute of Photoelectronic Thin Film Devices and Technology, State Key Laboratory of Photovoltaic Materials and Cells, Tianjin Key Laboratory of Efficient Solar Energy Utilization, Ministry of Education Engineering Research Center of Thin Film Photoelectronic Technology, Nankai University, 300350 Tianjin, China.

Hematite is a promising material for photoelectrochemical (PEC) water oxidation, but its photocurrent is limited by bulk charge recombination and poor oxidation kinetics. In this study, we report a high-performance FeO photoanode achieved through gradient surface gallium doping, utilizing a GaO overlayer on FeOOH precursors via atomic layer deposition (ALD) and co-annealing for Ga diffusion. The Ga-doped layer passivates surface states and modifies the band structure, creating a built-in electric field that enhances the charge separation efficiency.

View Article and Find Full Text PDF

To date, III-V semiconductor-based tandem devices with GaInP top photoabsorbers show the highest solar-to-electricity or solar-to-fuel conversion efficiencies. In photoelectrochemical (PEC) cells, however, III-V semiconductors are sensitive, in terms of photochemical stability and, therefore, require suitable functional layers for electronic and chemical passivation. GaN films are discussed as promising options for this purpose.

View Article and Find Full Text PDF

Carbon-based perovskite solar cells (C-PSCs) have the advantages of high stability and low cost, but their mean efficiency has become an obstacle to commercialization. Defects, which are widely distributed on the surface and bulk of films, are an important factor in C-PSCs for low efficiency. The conventional post-treatment method through forming a low-dimensional (LD) perovskite layer usually fails in manipulating the bulk defects.

View Article and Find Full Text PDF

Recent Advances on Characterization Techniques for the Composition-Structure-Property Relationships of Solid Electrolyte Interphase.

Small Methods

January 2025

College of Physics and Energy, Fujian Provincial Key Laboratory of Quantum Manipulation and New Energy Materials, Fujian Normal University, Fuzhou, 350117, China.

The Solid Electrolyte Interphase (SEI) is a nanoscale thickness passivation layer that forms as a product of electrolyte decomposition through a combination of chemical and electrochemical reactions in the cell and evolves over time with charge/discharge cycling. The formation and stability of SEI directly determine the fundamental properties of the battery such as first coulombic efficiency (FCE), energy/power density, storage life, cycle life, and safety. The dynamic nature of SEI along with the presence of spatially inhomogeneous organic and inorganic components in SEI encompassing crystalline, amorphous, and polymeric nature distributed across the electrolyte to the electrolyte-electrode interface, highlights the need for advanced in situ/operando techniques to understand the formation and structure of these materials in creating a stable interface in real-world operating conditions.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!