Secondary ion mass spectrometry has been used to investiage CVD SiO 2-germanijm MIS structures under various annealing conditions using several standards. For samples annealed in oxygen at 600°C, a GeO 2 film was formed between germanium and SiO21. Germanosilicate glass was found in the interface when the samples were subsequently annealed in Ar at 800°C. The oxidation of gamanium and formation of GeO2 or germanosilicate glass under these annealing conditions results in a lower interface state density. For samples annealed in Ar or a 10% H2-90% N2 forming gas, only a very thin GeO2 layer was presented and a very small difference in film thickness was observed. Such a small difference cannot explain fully the higher increase in interface state density when samples were annealed in forming gas. The investigation of hydrogen concentration indicates a hydrogen pileup near the germanium, is probably responsible for the high observed interface state density. Metallization, particulary with Al, complicates the studies. Furthermore, the release of hydrogen during the Al evaporation contributes to a high interface state density for samples annealed in forming gas. The effects of direct and recoiled ion implantation on the depth resolution during profiling is discussed. In addition, it is demonstrated that the profiling of contaminants may be used to identify the origins of contamination introduced during the processing.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)