Anisotropic RuO2 and Ru etching technology for gigabit dynamic random access memory has been developed using high density O-2+10% Cl-2 plasma in an inductively coupled plasma etching system. Under the conditions of low pressure, high gas flow rate, and large overetching times, we have demonstrated 0.2 mu m wide patterns in 0.3-mu m-thick RuO2/Ru films and 0.1 mu m wide patterns in 0.45-mu m-thick Ru films, both with an almost perpendicular taper angle of 89 degrees.