INFLUENCE OF TRICHLOROETHYLE (TCE) ON ROOM TEMPERATURE FLATBAND VOLTAGE OF MOS CAPACITORS

The investigations were carried out with several dry oxidation conditions such as variations in deposition temperature and time, gas flow rate, gettering ion and annealing. Several effects that reduce the oxide quality from the ideal one were observed. The presence of parasitic charges at the interface of oxide-semiconductor and within the oxide layer was taken into account using high frequency, quasistatic and heated plus biased C-V measurement. Also good thickness uniformity of gate-oxide is very important in MOS devices especially as design rules shrink to submicron range. For silicon dioxide (SiO2), the good flatness is important in the use of photolithography and as gate oxide. Trichloroethylene (TCE) can be effectively used to lower oxide charge mobile at room temperature (mostly H+ or H3O+ and perhaps some alkali ions) to values as small as 1.5x10 2/cm . Because of ease of handling, TCE is a good substitute for HCl in growing high quality oxides. For extremely high fields (larger than those normally encountered in device operation) the TCE-grown oxides exhibited a room temperature instability similar to that observed in Cl2-grown oxides. For high quality oxides there is an optimum flow rate of TCE during oxidation of about 2%. About this point, the introduction of additional positive mobile charge or donor-like traps in the oxide degrade the C-V characteristics. The incidence of low frequency behavior for large TCE flow rates indicates increased recombination activity at the interface or bulk silicon near the surface. Keywords :Dry halogen oxidation, TCE/O2, SiO2, Gate-oxide, Flatband voltage shifts, MOS capacitors

Nama : Slamet Widodo
Email : widodo@telkoma.lipi.go.id
Kategori : MICROELECTRONIC
Institusi : Indonesian Institute of Sciences (PPET-LIPI)