Microsystems Education without Using the Clean-Room Environment : Study of an Accelerometer Realized Using Printed Circuit Technology

Abstract

Working on a capacitive accelerometer allows students to learn about microsystems with a very simple technology. Starting from the specifications of the sensor, which have previously been computed (different for each group), students calculate its dimensions. When it is assembled, measurements are done in several conditions (continued accelerations and pulse excitation...). Specific electronic circuits are developed to get different oscillograms (JFET charge amplifier, variable frequency oscillator, controlled gain amplifier). From theses experimental results we can get the values of parameters in the theoretical model. Different kinds of measurements allow cross checking to test the coherence of the results.

Finally, more specific integrated circuits for microsystems are simulated with tools using behavioural or electrical models (MATRIXx, ELDO). These circuits are based on the principle of modulation and demodulation of the signal.