Chua´s chaotic oscillator as the GaAs manufacturing process state indicator

This paper presents the results of the measurements of a GaAs Chua´s circuit used for a new manufacturing process monitor. The proposed monitoring method is suggested to replace or complement the PCM which appears to be less predictive for more complex and nonlinear circuits. The chaotic signal generated by the circuit was recorded and the capacitor voltage equilibrium points were recovered from the time-series. It is shown that there exists a strong correlation between the equilibrium points´ separation and many of the PCM parameters, such as transistor threshold voltage and drain current. The correlation demonstrates that the Chua´s circuit is sensitive to the process variations which makes this circuit a vital candidate for the circuit control monitor (CCM).