2021 IEEE EDS Final Year Project Award
Soumik Bhattacharjee was won for 2021 Award of Excellence in Final Year Project, which supervised by Ts. Dr. Ahmad Anwar Zainuddin. This achievement was awarded by IEEE EDS Malaysia Chapter. Soumik Bhattacharjee was recently graduated from School of Engineering and Computing under Computer Engineering faculty. This work describes The Quartz Crystal Microbalance (QCM) becomes a nanogram-level mass sensor when a high-frequency thickness shear mode piezoelectric crystal is activated. These sensors provide high-precision detection while maintaining a basic geometry, low cost, and ease of production. Due to their single-electrode form, typical QCM sensors are limited in their detecting capabilities. Apart from that, this work also develops and optimizes a few novel multi-channel QCM (MQCM) sensors on a single quartz crystal substrate – dual channel, triple channel, and quadruple channel QCM sensors. Each type of MQCM has a unique resonance frequency, coupling effect, mass sensitivity, and inter-channel (c2c) distance. This work proposes to design and optimize a QCM array using the COMSOL Multiphysics. The comparison of the performance of various QCM array configurations (dual, triple, quad) for the aim of smell characterization of volatile organic compounds is studied. As a starting point, a sensor with the appropriate sensor film is done to investigate its behavior in terms of Volatile Organic Compounds (VOC) detection. The sensor designs incorporate a constant quartz thickness of 168m, a 2000µm gold radius, and a 400nm electrode thickness. To carry out a COMSOL analysis on three different multi-channel QCMs design scenarios, the theoretical framework is employed. Depending on the application region, the design of a MQCM may need to be modified to accommodate for environmental conditions. As a result, using Sauerbrey’s equation, the sensor achieved a mass sensitivity of about 17.39 Hz.cm2.ng-1. The coefficient of determination is obtained as 95.64% for 0-100ppm concentration of acetone based on this simulation. Thus, if each QCM is coated with the appropriate sensing material, it has the potential to detect multiple gas targets without crosstalk error (unwanted conductive connection between two or more channels).