A shower head (10C) has at least one mixing chamber (24) having an air inlet (18) for connection to a supply of pressurized air and a water inlet (22) for connection to a supply of pressurized water so that, in use, the air breaks the water up into droplets in the mixing chamber. The mixing chamber further has at least one outlet (32) so that, in use, the water droplets and air exit the shower head to form a shower of water droplets having a mean trajectory. The or each outlet is arranged so that, in use, at least a substantial proportion of the water droplets exit the shower head so that their individual trajectories on leaving the shower head are offset from the mean trajectory of the shower head and converge towards the mean trajectory of the shower head. This can result in a more uniform distribution of water droplets in the shower pattern. A single annular outlet may be provided, or a plurality of separate outlets. In order to assist in breaking up the water into small droplets, a vortex may be induced in the air and/or the water in the mixing chamber, and/or a deflector may be disposed adjacent the water inlet into the mixing chamber.

A cleaning device for atomizing and spraying liquid in two-phase flow comprising a nozzle provided with multiple liquid bypass pipelines each having liquid guiding outlets inclined at a predetermined angle and an exhaust mesh plate having vertical gas guiding outlets, which makes the high speed liquid flow and high speed gas flow sprayed out therefrom collide against each other sufficiently to form ultra-micro atomized particles with uniform and adjustable size. The ultra-micro atomized particles are sprayed out downwardly to the wafer surface under the acceleration and vertical orientation effects of an atomized particle guiding outlet to perform a reciprocating cleaning for the wafer. Other components such as an ultrasonic or megasonic generation unit, a gas shielding unit, a self-cleaning unit or a rotating unit can also be provided to perform the multifunction of the nozzle.

A steam atomizing liquid spraying system which in the preferred embodiment includes a spray nozzle assembly having a central liquid passageway for coupling to a liquid supply and a plurality of spray nozzles each removably mounted in the nozzle body and having a respective central steam passage communicating with a steam supply. The spray nozzles each further have a plurality of circumferentially spaced liquid accelerating passages that communicate with a respective angled passage of the nozzle body which in turn communicates with the central liquid supply passageway for directing liquid into the central steam passage of the spray nozzle for interaction with steam directed through the central steam passage and atomization of liquid discharging from the spray nozzle. In an alternative embodiment, a single spray nozzle insert is utilized.