A monolithic zinc-oxide-on-silicon convolver

A monolithic convolver using rf-sputtered zinc oxide deposited on silicon was constructed and operated at a center frequency of 120 MHz. The electronic efficiency obtained with this device F = Pout/Pin1Pin2, using 100-Ω cm silicon, was −70 dB m. This corresponds to an input-output efficiency of approximately −50 dB with a 20-dB m reference signal. These results agreed well with our theoretical expectations for the device. The theory predicts that with a properly optimized device, the electronic efficiency F can be of the order of −50 dB m.