Investigation of the effects of Ar plasma etching in Si surface by photoacoustic method

Abstract

The effects of Ar plasma treatment on the Si surface were investigated by photoacoustic spectroscopy and atomic force microscopy. We studied the surface structure as a function of plasma experimental parameters to correlate the plasma-surface reaction with surface roughness, surface defects and thermal and electronic transport characteristics. The surface of the Si sample (p-type, 10 k$\Omega$cm, 420 $\mu$m) was treated with Ar plasma from 2 min to 80 min. Amplitude and phase PA spectra were measured in the energy range from 0.75 to 1.55 eV. The amplitude ratio and phase difference of the photoacoustic signals for Si samples Ar plasma etched and incoming Si samples indicate the existence of two surface energy states (the generation-recombination centers) at 0,81 and 0,99 eV.