A Microbeam Resonator With Partial Electrodes for Logic and Memory Elements

We demonstrate logic and memory elements based on an in-plane clamped-clamped microbeam resonator. The microresonator is electrostatically actuated through a drive electrode and the motional signal is capacitively sensed at a sense electrode, while the resonance characteristics are modulated by dc voltage pulses provided at two separate partial electrodes, independent of the drive/sense electrodes. For the logic applications, we use two separate electrodes to provide dc voltages defined as the logic inputs. The high (low) motional signal at on-resonance (off-resonance) state is defined as the logic output state “1”(“0”). For the memory operation, two stable vibrational states, high and low, within the hysteretic regime are defined as the memory states, “1”and “0,”respectively. We take advantage of the split electrode configuration to provide positive and negative dc voltage pulses selectively to set/reset the memory states (“1”/“0”) without affecting the driving and sensing terminals. Excluding the energy cost for supporting electronics, these devices consume energy in tens of picojoules per logic/memory operation. Furthermore, the devices are fabricated using silicon-on-insulator wafers, have the potential for on-chip integration, and operate at moderate pressure (~1 Torr) and room temperature.