A new, very high rate dry etching system based on the plasma jet principle is presented. In this device the active gases are fed into the processing vacuum chamber through a small 0.5 mm i.d. nozzle. By applying radio frequency power (13.56 MHz) a hollow cathode discharge is created inside the nozzle. This discharge will be very intense and effective in dissociating the gas mixture used for reactive etching. A jet stream of radicals will be formed. By placing a silicon substrate in front of this jet stream it is possible to perform very high rate reactive etching of silicon. Etch rates as high as 0.1–0.2 mm/min can be easily obtained. It is demonstrated that the etch rate and the width of the etching crater are sensitive to different processing conditions. The width of the etching crater may be smaller than the diameter of the nozzle exit under certain conditions.