High-Performance Superthin Oxide/Nitride/Oxide Stacked Dielectrics Formed by Low-Pressure Oxidation of Ultrathin Nitride

Abstract

The stabilization of drift modes occurring in a plasma with several kinds of different masses and temperatures (such as impurity ions or trapped particles in curved magnetic field configurations) is studied. The possibility of the reduction of growth rates by applying an electromagnetic H.F. field with a dominant magnetic component is discussed.

Excellent low-pressure-oxidized Si3N4 films on roughened poly-Si for high-density DRAMs

“…In constrast, the capacitors with APO express a wider distribution than those with LPO, particularly in positive gate-bias ( Vg). It has been reported that low pressure oxidation of thin nitride film is able to grow the oxide on the top and bottom of the nitride layers and only bottom oxide formed for the atmospheric pressure oxidation [7]. Therefore, an ONO stacked dielectric was formed on the roughened poly-Si surface in LPO samples and only NO structure in APO samples.…”

“…However, the current densities are 4.15 10 A/cm and 2.75 10 A/cm at the same biases for the APO sample and they are higher than one order as compared to LPO ones. The reduction in leakage current for LPO is believed to be due to the formation of ONO stacked structure on the roughened poly-Si [7]. Therefore, the technique of low-pressure oxidation can not only decrease the leakage current but also decrease with respect to the APO one.…”

“…From the calculated equation of the capacitance, there are three ways to increase the capacitance of DRAM capacitors. One is to enlarge the effective surface area of the storage-nodes [1]- [5], another is to reduce the thickness of the dielectrics [6], [7], and the other is to utilize high dielectric constant materials [8]. Many advanced structures have been investigated to increase the surface area of the storage-nodes, however, it is difficult to carry out these complicated storagenode structures by using conventional processes.…”