Reactive Ion Etching Damage to Strained Si1-xGex Heterojunction Diodes

This work describes the experimental results of the effect of dry etching on the electrical characteristics of strained Si_1-xGe_x/Si p⁺-n heterojunctions. An increase in the series resistance and a dominance in recombination current is noticed from the I-V characteristics of the dry etched devices. A degradation in the device characteristics due to the introduction of active states at the interface is seen in the high frequency C-V measurements. This indicates that the process induced damage can introduce mis-fit dislocations at the silicon and silicon germanium interface which in turn seriously limit the electrical characteristics of the device.