Charge trapping and interface state generation in metal-oxide-semiconductor capacitors due to Fowler–Nordheim tunneling injection at low temperatures

Abstract

Electrical phenomena in metal-oxide-semiconductor capacitors caused by Fowler–Nordheim tunneling injection of electrons have been studied at temperatures ranging from 77 to 300 K. It has been found that the shift of flatband voltages (ΔVFB) depends on the oxidation temperature and that low-temperature oxidation is desirable for the reduction of ΔVFB . The dependence of ΔVFB on the injection temperature shows a characteristic feature: The ΔVFB reduces with decreasing injection temperature in the range above 180 K and, on the other hand, is almost independent of the injection temperature in the range below 180 K. These results are mainly attributable to the injection temperature dependence of interface state generation. The injection temperature dependence of interface state density clearly indicates that two generation mechanisms of interface states are present. In addition, we have found a power-law dependence of the generated interface states on ΔVFB, independent of oxidation and injection conditions.