CHARACTERIZATION OF THIN SIN FILM FORMED WITH ELECTRON-CYCLOTRON-RESONANCE NITROGEN PLASMA

An extremely thin SiN film formed with electron cyclotron resonance (ECR) nitrogen plasma has been measured by x-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), ellipsometry, and electron spin resonance (ESR). The XPS and AES results show that the SiN layer is easily formed on a silicon surface by ECR nitrogen plasma, and it has a structure with high nitrogen content similar to Si3N4 only near the surface of the film. The ellipsometry and ESR results reveal that the SiN film is very thin, 2.5-4.0 nm, and has spin density in order of 1013 cm-2, which is reduced drastically by exposing it to hydrogen plasma. The SiN film can be applied to the inexpensive dual-polycide-gate complementary metal-oxide-semiconductor process.