Abstract: An apparatus for depositing a selected pattern of solder onto a substrate comprising: a substrate support having structure for bearing a substrate on which one or more electronic components are to be mounted; a solder ejector that defines a cavity for containing molten solder and an orifice for ejecting a stream of molten solder; a heater for heating the solder to a temperature above the melting point of solder; a vibrator coupled to the solder ejector to form droplets in the stream at the desired frequency for deposition onto the substrate; and a cooler, adapted to receive a coolant, disposed between the heater and the vibrator to maintain the temperature of the vibrator below that which would detrimentally affect the performance of the vibrator.