Solid state switch for gigahertz coded signal ultrasound microscopy

Presented is a solution for ultrasonic microscopy that permits using coded gigahertz signals. It features a high frequency arbitrary signal source (upconverted quadrature I-Q modulation), a solid state switch, and a preamplifier. Commercial 3 GHz solid state switches that handle 15 Vpp signals and a 0.01–1.2 GHz low noise preamplifier (3.3 dB noise figure) were used, all developed for wireless networking. The device was validated with a custom built ultrasound immersion microscope by imaging a 5 µm-tall MEMS step structure using 100–300 MHz, 3 µs, 10.5 Vpp linear chirp excitation.