title: Top-Down Nanofabrication and Characterization of 20 nm Silicon Nanowires for Biosensing Applications.
abstract: A top-down nanofabrication approach is used to develop silicon nanowires from silicon-on-insulator (SOI) wafers and involves direct-write electron beam lithography (EBL), inductively coupled plasma-reactive ion etching (ICP-RIE) and a size reduction process. To achieve nanometer scale size, the crucial factors contributing to the EBL and size reduction processes are highlighted. The resulting silicon nanowires, which are 20 nm in width and 30 nm in height (with a triangular shape) and have a straight structure over the length of 400 μm, are fabricated precisely at the designed location on the device. The device is applied in biomolecule detection based on the changes in drain current (Ids), electrical resistance and conductance of the silicon nanowires upon hybridization to complementary target deoxyribonucleic acid (DNA). In this context, the scaled-down device exhibited superior performances in terms of good specificity and high sensitivity, with a limit of detection (LOD) of 10 fM, enables for efficient label-free, direct and higher-accuracy DNA molecules detection. Thus, this silicon nanowire can be used as an improved transducer and serves as novel biosensor for future biomedical diagnostic applications.
authors.affiliation: Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, 01000 Kangar, Perlis, Malaysia.
authors.forename: M N
authors.initials: MN
authors.lastname: M Nuzaihan
authors.affiliation: Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, 01000 Kangar, Perlis, Malaysia.|School of Microelectronic Engineering, Universiti Malaysia Perlis (UniMAP), 02600 Pauh, Perlis, Malaysia.
authors.forename: U
authors.initials: U
authors.lastname: Hashim
authors.affiliation: Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, 01000 Kangar, Perlis, Malaysia.|School of Microelectronic Engineering, Universiti Malaysia Perlis (UniMAP), 02600 Pauh, Perlis, Malaysia.
authors.forename: M K
authors.initials: MK
authors.lastname: Md Arshad
authors.affiliation: Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, 01000 Kangar, Perlis, Malaysia.
authors.forename: A
authors.initials: A
authors.lastname: Rahim Ruslinda
authors.affiliation: Chemistry Department, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia.
authors.forename: S F A
authors.initials: SF
authors.lastname: Rahman
authors.affiliation: Institute of Nano Electronic Engineering, Universiti Malaysia Perlis, 01000 Kangar, Perlis, Malaysia.
authors.forename: M F M
authors.initials: MF
authors.lastname: Fathil
authors.affiliation: School of Microelectronic Engineering, Universiti Malaysia Perlis (UniMAP), 02600 Pauh, Perlis, Malaysia.
authors.forename: Mohd H
authors.initials: MH
authors.lastname: Ismail
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D018076:DNA, Complementary / Q000032:analysis; D004560:Electricity; D004583:Electrons; D044085:Microfluidics; D018625:Microscopy, Atomic Force; D036103:Nanotechnology / Q000379:methods*; D053770:Nanowires / Q000737:chemistry* / Q000648:ultrastructure; D010316:Particle Size; D012825:Silicon / Q000737:chemistry*
chemical_list: D018076:DNA, Complementary; D012825:Silicon