Optical functions of chemical vapor deposited thin-film silicon determined by spectroscopic ellipsometry

Abstract

The optical functions of several forms of thin‐film silicon (amorphous Si, fine‐grain polycrystalline Si, and large‐grain polycrystalline Si) grown on oxidized Si have been determined using 2‐channel spectroscopic polarization modulation ellipsometry from 240 to 840 nm (∼1.5–5.2 eV). It is shown that the standard technique for simulating the optical functions of polycrystalline silicon (an effective medium consisting of crystalline Si, amorphous Si, and voids) does not fit the ellipsometry data.