Process for etching a polycristalline Si1-xGex layer or stacked layers of polycristalline Si1-xGex and Si, and application to electronic devices

摘要

The method of etching a layer of Si _1-x Ge _x polycrystalline or a stack of a layer of Si _1-x Ge _x and a polycrystalline Si layer deposited on a polycrystalline substrate and having on its surface inorganic material in a mask includes a step of main etching, anisotropic, said layer or the said stack using said mask, by means of a high-density gas plasma of a gas mixture consisting of chlorine (Cl ₂₎ and or nitrogen (N ₂₎ or ammonia (NH _3), or a mixture of nitrogen and ammonia.; Application: in the manufacture of gate structures for CMOS devices.