Passivation for Selective Plasma Etching
Original Publication Date: 1987-Nov-01
Included in the Prior Art Database: 2005-Feb-02
The plasma removal of an inorganic layer from a substrate, when the inorganic layer is covered in imagewise configuration with an organic mask, is accomplished in the following method. The mask 1 (Fig. 1) is fluorinated when exposed to a high CF4/low O2 plasma in the presence of an ion shield 2. The O2 content of the plasma is then raised to remove the exposed metal layer 3 from a substrate 4 while the fluorinated organic mask 1 is not affected because it is protected by the ion shield. The resulting structure is seen in Fig. 2. The fluorination can be removed from the mask by etching for a short period in a high O2 plasma, while the ion shield is removed (Fig. 3).