A DNA probe synthesis system may include a target holder for holding a target chip, an ejector array chip, a wash and dry station, and conveyance means for moving the target holder and the chip between the ejector array chip and the wash and dry station. The ejector array chip may include ejectors, reservoirs for containing DNA bases, and microchannels all on the same substrate. The ejectors may be Self Focusing Acoustic Transducers (SFATs).
