The article describes preparation and characterization of a silicon surface modified by different selfassembled aminopropylsilanes with the purpose of using them in sensor applications. Singlecrystal silicon wafers (111) were modified with aminosilanes that have different numbers of bonding sites: 3aminopropyltrimethoxysilane (APTMS), 3aminopropyl diethoxymethyl silane (APRDMS) and 3aminopropylethoxydimethylsilane (APREMS). We deposited the selfassembled layers from a solution of aminosilanes in toluene under various reaction conditions. The surface composition and the chemical bonding were determined using Xray photoelectron spectroscopy.
COBISS.SI-ID: 36892165
We compare the sensitivities for vapor trace detection of Trinitrotoluene (TNT) explosives of two different sensor systems: a chemo-mechanical sensor based on chemically modified Atomic Force Microscope (AFM) cantilevers based on Micro Electro Mechanical System (MEMS) technology with optical detection (CMO), and a miniature system based on capacitive detection of chemically functionalized planar capacitors with interdigitated electrodes with a comblike structure with electronic detection (CE). Using CMO system, we can detect 300 molecules of TNT in 10+12 molecules of N2 carrier gas, whereas the CE system can detect three molecules of TNT in 10+12 molecules of carrier N2.
COBISS.SI-ID: 10678868
3aminopropyltrimethoxysilane (APTMS) was used for the modification of Singlecrystal silicon wafers (1 1 1). We deposited the self-assembled layers from a solution of APTMS, in five solvents, with different polarities, under various reaction conditions. The influence of the different solvents on the morphology of the modified surfaces was studied, since the possible heterogeneity may significantly influence the application of such surfaces.
COBISS.SI-ID: 1715759
This article presents the design of a miniature detection system and its associated signal processing electronics, which can detect and selectively recognize vapor traces of different explosives in the air. It is based on the array of surface-functionalized COMB capacitive sensors and extremely low noise, analog, integrated electronic circuit, hard-wired digital signal processing hardware and additional software running on a PC. The instrument is sensitive and selective, consumes a minimum amount of energy, is very small (few mm3), and is insensitive to mechanical influences. Using an electronic detection system built of low noise analog front-end and hard-wired digital signal processing, it is possible to detect less than 3 TNT molecules in 1012 molecules of the air at 25oC on a 1 Hz bandwidth using 10 mA current from a 5V supply voltage.
COBISS.SI-ID: 11045716
In this paper, we present a miniature multi-channel sensor detection system, based on chemically functionalized COMB micro-capacitors, low noise integrated electronics and digital signal processing, which is able to measure vapor traces of different materials simultaneously using array of sensors, analog signal processing electronics, as well as appropriate digital signal processing hardware and software algorithms.
COBISS.SI-ID: 10503252