A plurality of oligonucleotides are synthesized at a plurality of locations on a substrate using a plurality of dispensing bars. Each of the plurality of dispensing bars has a respective plurality of dispensing heads arranged along a respective axis. Each of the plurality of dispensing bars is operative to selectively deposit a volume of a respective one of a plurality of nucleotide bases in any of a row of locations. A positioning mechanism positions the substrate with respect to the plurality of dispensing bars. A controller controls the plurality of dispensing bars and the positioning mechanism so that, at each of the plurality of locations, a respective sequence of nucleotide bases is deposited to form a respective oligonucleotide.