Reduction of Radiation Damage on Silicon Substrates in Magnetron Reactive Ion Etching

Radiation damage on silicon substrates has been reduced by decreasing the cathode dc bias in reactive ion etching (RIE). A magnetic field has been applied in the direction perpendicular to RF electric field between the parallel‐plate electrodes to decrease the dc bias across the cathode dark space. Silicon substrates treated under RIE in and mixed gas have been investigated by reflection high energy electron diffraction observation and lifetime measurement of the minority carrier. Low dc bias less than about 150V was found to be necessary for obtaining low damaged silicon surface.