Engineering topics

Islam, Syed K.

Publications and source records attributed to Islam, Syed K..

4 records

DOE OSTI2018

A Charge Sensitive Pre-Amplifier for Smart Point-of-Care Devices Employing Polymer Based Lab-on-a-Chip

With increasing emphasis on implantable and portable medical devices, low-power, small-chip-area sensor readout system realized in lab-on-a-chip (LOC) platform is gaining more and more importance these days. The main building blocks of the LOC system include a front-end transducer that generates an electrical signal in response to the presence of an analyte of interest, signal processing electronics to process the signal to comply with a specific transmission protocol and a low-power transmitter, all realized in a single integrated circuit platform. Low power consumption and compactness of the components are essential requirements of the LOC system. This paper presents a novel charge sensitive pre-amplifier developed in a standard 180-nm CMOS process suitable for implementing in an LOC platform. The pre-amplifier converts the charge generated by a pyroelectric transducer into a voltage signal, which provides a measurement of the temperature variation in biological fluids. The proposed design is capable of providing 0.8-mV/pC gain while consuming only 2.1 μW of power. Finally, the pre-amplifier composed of integrated components occupies an area of 0.038 mm 2 .

36 MATERIALS SCIENCE↗

DOE OSTI2017

A Novel Charge Sensitive Pre-Amplifier Structure for Biological Temperature Readout Applications

Charge sensitive pre-amplifier architectures have been studied for decades for various applications, most of which adopt a gain stage with capacitor feedback to integrate the signal and a reset path to provide DC bias. For the biological temperature readout front-end, we propose a novel structure without the gain stage, which implies a strong potential for fully integrated high frequency applications. The proposed design provides 0.94 mV/pC with high conversion linearity while consuming only 1.4 micro watts of power with buffer under a 1.2-V supply rail. The prototype occupying a chip area of 0.038 square millimeter is fabricated in 130 nm standard CMOS process.

Wang, Hangfeng↗

DOE OSTI2014

Vertically Aligned Carbon Nanofiber based Biosensor Platform for Glucose Sensor

Vertically aligned carbon nanofibers (VACNFs) have recently become an important tool for biosensor design. Carbon nanofibers (CNF) have excellent conductive and structural properties with many irregularities and defect sites in addition to exposed carboxyl groups throughout their surfaces. These properties allow a better immobilization matrix compared to carbon nanotubes and offer better resolution when compared with the FET-based biosensors. VACNFs can be deterministically grown on silicon substrates allowing optimization of the structures for various biosensor applications. Two VACNF electrode architectures have been employed in this study and a comparison of their performances has been made in terms of sensitivity, sensing limitations, dynamic range, and response time. The usage of VACNF platform as a glucose sensor has been verified in this study by selecting an optimum architecture based on the VACNF forest density. Read More: http://www.worldscientific.com/doi/abs/10.1142/S0129156414500062

Al Mamun, Khandaker A.↗

DOE OSTI2014

Enhancement of surface phonon modes in the Raman spectrum of ZnSe nanoparticles on adsorption of 4-mercaptopyridine

By chemically etching a thin film of crystalline ZnSe with acid, we observe a strong Raman enhancement of the surface phonon modes of ZnSe on adsorption of a molecule (4-mercaptopyridine). The surface is composed of oblate hemi-ellipsoids, which has a large surface-to-bulk ratio. The assignment of the observed modes (at 248 and 492 cm{sup −1}) to a fundamental and first overtone of the surface optical mode is consistent with observations from high-resolution electron energy loss spectroscopy as well as calculations.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗