The impact of nitrogen plasma nitridation on the interfacial quality of ultrathin oxides ͑1.8 and 2.6 nm͒ have been investigated and compared with NO nitridation. It is found that plasma-nitrided oxides are more immune to nitridation-induced degradation of channel hole mobility, and have lower intrinsic interface-trap density as compared to NO-nitrided oxides. In addition, plasmanitrided oxides can further suppress hole mobility degradation induced by boron penetration. The superior performance of nitrogen plasma nitridation is attributed to its capability of incorporating a high level of nitrogen at the top oxide surface, while keeping the Si-SiO 2 interface intact.Introducing nitrogen into thin silicon dioxide films using NO nitridation has been widely employed in complementary metaloxide-semiconductor ͑CMOS͒ technology to suppress impurity penetration and enhance resistance to hot-carrier aging. 1-3 However, it has been widely recognized that nitrided oxides generally suffer significant degradation of channel hole mobility across all electric fields as compared to pure SiO 2 . 1,4-7 On the other hand, nitrogen plasma nitridation has recently attracted considerable interest over NO nitridation for sub-0.13 m CMOS technology because of its superior efficiency in tailoring a higher amount of nitrogen near the polysilicon/SiO 2 interface. This nitrogen-rich layer not only increases the dielectric constant of an oxynitride which can be used for reducing tunneling leakage current, but also acts as an excellent barrier to suppress impurity penetration. [8][9][10][11] However, the impact of plasma nitridation on channel hole mobility has not been assessed so far. In this paper, we have studied the effects of the plasma nitridation process on the channel hole mobility and interface-trap density of ultrathin gate oxides. We found that plasma-nitrided oxides exhibit improved immunity to the degradation of channel hole mobility induced by nitridation as compared to NO-nitrided oxides, also retard the boron-induced mobility degradation. Additionally, we show a close association between the degradation of channel hole mobility and the interface traps induced by nitridation and boron penetration. ExperimentalDevices were fabricated using 0.13 m dual-gate CMOS technology. After shallow trench isolation and twin-well formation, base oxides with optical thickness of 1.8 and 2.6 nm were grown by rapid thermal oxidation. The plasma-nitrided oxides were prepared by exposing the base oxides to an ex situ high-density decoupled nitrogen plasma source at room temperature. These oxides are referred to as decoupled plasma-nitrided oxide ͑DPNO͒ hereafter for brevity. On the other hand, rapid thermal nitrided oxides ͑RTNO͒ were formed by subjecting the base oxides to in situ rapid thermal nitridation in a NO ambient. Upon nitridation, both DPNO and RTNO received identical postnitridation annealing. Subsequently, 160 nm undoped polysilicon was deposited and patterned. p ϩ -Poly gate and p ϩ -source/drain were formed simultaneously by B im...

Zinc oxide (ZnO) quantum dots (QDs) embedded films were fabricated on silicon substrates by metal organic chemical vapor deposition at 350 o C. The QDs can be obtained in a matrix of amorphous ZnO films by introducing a large amount of precursors. The size of the QDs ranged from 3 to 12 nm, which was estimated by high-resolution transmission electron microscopy. The photoluminescence measured at 80 K showed that the emission of QDs embedded film ranged from 3.0 to 3.6 eV. The broad near-band-edge emission is due to the quantum confinement effect of the QDs. The quantum confinement effect of the QDs was quenched after the post-growth annealing due to the ripening of QDs. EXPERIMENTThe ZnO QDs used in this paper were embedded in a matrix of amorphous ZnO films grown on Si (100) by MOCVD. The growth temperature was set at 350 o C. DimethylZinc (DMZn), N 2 gas and high-purity O 2 were used as the zinc source, carrier gas and oxidizing agent, respectively.