The present invention relates to a method of forming arrays of oligonucleotides on a solid support. This method involves providing a solid support having an array of positions each suitable for attachment of an oligonucleotide. Linkers, suitable for coupling oligonucleotides to the solid support, are attached to the solid support surface at each of the array positions. An array of a plurality of capture oligonucleotides are formed on the solid support by a series of cycles of activating selected array positions for attachment of multimer nucleotides and attaching multimer nucleotides at activated array positions. The multimer nucleotides are selected for attachment so that the capture oligonucleotides formed on the array hybridize with complementary oligonucleotide target sequences under uniform hybridization conditions.