Localized heating of biological media using a 1-W microwave near-field probe

A medium power microwave near-field probe operating at 9 GHz has been designed and tested. The probe radiates microwave energy through a very narrow slot microfabricated at the apex of the dielectric resonator. The radiation is very intensive at near-field distances from the slot and is capable of heating different materials. A temperature of ∼60°C-100°C is achieved in an irradiated spot of a size as small as 270×500μm². This probe may be used for selective irradiation of biological tissues and tissue welding. We demonstrate the probe ability to produce irreversible changes in biological media with a relatively low power source of ∼1 W. This feature makes it safe for usage in biomedical settings and opens the way to development of an inexpensive portable handheld device.