Direct synthesis and properties of K2SiF6:Mn4+ phosphor by wet chemical etching of Si wafer

A new method of synthesizing Mn-activated phosphor is presented. The method uses only chemical etching of Si wafer in HF/H2O solution with the addition of an oxidizing agent KMnO4. The luminescence centers of red emission are ascribed to Mn4+ ions in the octahedral sites of potassium hexafluorosilicate (K2SiF6). The luminescence intensity becomes much stronger at higher temperatures, without largely changing its spectral feature.