A Computer Controlled Measurement System to Characterize Quartz Crystal Oscillator Gas Sensors Hazem Zanoun Electrical Engineering Department

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A Computer Controlled Measurement System to
Characterize Quartz Crystal Oscillator Gas
Sensors Hazem Zanoun Electrical
Engineering Department
A computer controlled measurement system is
being developed to measure response of Quartz
Crystal Oscillator sensors to gas concentration.
The quartz crystal senses the amount of the gas
absorbed by a thin film of material coated on its
surface by changing its resonant frequency. The
thin film coating has a specific selectivity for
the gas to being detected. The system uses
LabView as the platform for interfacing,
communication, data acquisition and control
between a personal computer and the measurement
setup via GPIB bus and serial ports. In the
system a closed air circulation is used with the
gas to be sensed mixed into the system via
computer controlled mass flow controllers. The
LabView program written controls the timing and
the amount of the gas injection. After each
injection the program triggers all measurement
instruments and gathers data to quantify and
generate plots of sensor response vs. injected
gas concentration. This work is being developed
under the guidance of Dr. M.G. Guvench,
University of Southern Maine professor of
Electrical Engineering.
6 MHz Quartz Crystal Oscillator Sensor
High Performance Thin Film Thickness/Rate
Deposition Monitor Oscillator
A Third Party LabView Environment Is being
Developed to Obtain The Frequency Directly From
The Oscillator For verifying The Data Obtained By
The Main Software
The Frequency of The Crystal is Obtained through
an Oscilloscope
Using RS232 communications , the LabVIEW software
and lab PC allows quick and simple results to be
obtained from the film