Etching characteristics of TiN film have been investigated in SF6/Ar h
elicon plasma. The etch rate of TiN film increases with increasing sou
rce power, bias power and temperature, exhibits a maximum at a moderat
e pressure as a function of pressure. A possible mechanism of titanium
fluoride formation is proposed based on the results of optical emissi
on spectroscopy (OES). In order to determine the effect of titanium fl
uorides on tungsten etching, the loading effect in tungsten etchback i
s investigated as a function of source power, bias power and temperatu
re. Using secondary ion mass spectrometry (SIMS), the relative concent
rations of titanium fluorides redeposited on tungsten are measured by
varying the bias power and temperature. The loading effect is reduced
by enhancing the redeposition of titanium fluorides on a tungsten plug
with increasing source and bias power. The loading effect is also ret
arded by lowering the temperature.