Restriction of Hazardous Substances Directive a disadvantage because it can lead to lower quality electrical connections – can be used to place components more tightly than they used to be placed due to the properties of lead-containing solders. For example, Motorola reports that their new RoHS wireless device assembly techniques are "...enabling a smaller, thinner, lighter unit." Their Motorola Q phone would not have been possible without the new solder. The lead-free solder allows for tighter pad spacing. Research into new alloys and technologies is allowing companies to release RoHS products that are currently exempt from compliance, "e.g." computer servers. IBM has announced a RoHS
Ultrasonic soldering different process than ultrasonic welding. Ultrasonic welding uses ultrasonic energy to join parts without adding any kind of filler material while ordinary soldering uses external heating to melt filler metal materials, namely solders, to form a joint. Ultrasonic soldering can be done with either a specialized soldering iron or a specialized solder pot. In either case the process can be automated for large-scale production or can be done by hand for prototyping or repair work. Initially, U/S soldering was aimed at joining aluminum and other metals; however, with the emergence of active solders, a much wider range of metals, ceramics