Brooks Instrument offers a new Safe Delivery System (SDS) option for its GF120 low-pressure drop mass flow controller that delivers sub-atmospheric SDS gases used in implant and etch processes. Sub-atmospheric SDS gases are adsorbed onto a solid medium within the gas cylinder, remaining below atmospheric pressure despite containing up to 15 times more dopant than conventional pressurized sources. Most mass flow controllers require a 50 Torr differential pressure at flowrates of 5 sccm in which only about 65 percent of the dopant can be extracted. The GF120 SDS low-pressure operation enables a further 30 percent of the dopant to be extracted, providing cost-savings in SDS gases and equipment. The GF120 SDS models may also be used in other challenging applications that require low-pressure drop. These devices are available in full-scale flow ranges from 4 sccm to 1 slpm.