Anuar Ahmad

Design and Fabrication of Polysilicon‐based Piezoresistive Microcantilever For Biological Sensing

This paper describes the fabrication process of a piezoresistive microcantilever sensor that is used as a platform for biological sensing such as salivary amylase‐activity. The 0.5 μm‐thick piezoresistive sensors are made on polysilicon‐based cantilever beam. This surface micromachined microcantilever is based on silicon wafers and fabricated using 0.5 μm CMOS process technology . The range of microcantilevers is 40–140 μm long, 0.5–1 μm thick, and 40 μm wide. The force sensitivity of implemented sensors ranges from 2–10 Pa is corresponding to salivary amylase‐activity adsorbed on the piezoresistive microcantilever.

The Synthesis of VACNTs Grown on MgxZn1-xO (0< x <0.3) Template

In this study, MgxZn1-xO thin film with x varied from 0 to 0.3 was deposited on silicon with the orientation of [1 0 0] using the sol-gel method and spin coating technique. The thin film was annealed at 550°C before being used as a template to grow vertically aligned carbon nanotubes (VACNTs). Field emission scanning electron microscopy (FESEM) indicates that the top view of VACNTs’ topography are very similar to the topography of the template used, MgxZn1-xO thin film. When the value of x increased, the grain size of the template becomes larger and rougher, which were also true with the VACNTs. The electrical properties were measured using IV measurement system, which indicates that the conductivity of the VACNTs is directly proportional to the grain size of the template. Raman spectroscopy was used to inspect the crystal orientation.

Synthesis of Supergrowth VACNTs and Nanostructured ZnO by Immerse Method

In this paper, the study of supergrowth VACNTs after being immersed in zinc oxide solution were presented. Vertically aligned carbon nanotubes (VACNTs) were first deposited on silicon with the orientation of [1 0 0] before being immersed in an aqueous solution of zinc nitrate hexahydrate and hexamethylenetetramine. Physical changes have been observed by scanning electron microscopy, SEM in the VACNTs, where the significant expansion of length of up to almost 0.8 mm was achieved after the immersion of 4.5 hr. The supergrowth of VACNTs was observed and analyzed by energy dispersive x-ray spectroscopy, EDX to substantiate the incorporation of CNTs and ZnO of the sample. Raman spectroscopy and x-ray diffraction, XRD were used to inspect the crystal orientation to support our findings.