Micromachined silicon needle for ultrasonic surgery

A micromachined silicon needle structure capable of producing large ultrasonic velocities (~23 m/s) was fabricated. Such a device can be used as a surgical tool. The device consists of two silicon ultrasonic horns bonded with a channel along the length to form the needle. Silicon´s acoustical and mechanical properties make it an ideal resonator material for the body of an ultrasonic cutter. Cutting edges sharper than the conventional needles can be produced using the silicon anisotropic etching process. As a proof of concept, a human eye cataractous lens was dissected with the silicon ultrasonic needle