We have succeeded to prepare a hgh quality silicon nitride gate insulator with lower gate leakage current in three orders of magnitude compared to that of conventional thermal oxide film, by using a Kr/NH3 mixed gas microwave-excited highdensity plasma with metal (TaN/Ta/TaN) gate. Moreover, we have evaluated the current drive capability dependence on the silicon surface orientation and found that the channel hole mobility on (1 10) surface at the channel-width direction of 13 5 degree from the (111) cut plane was 2.4 times hlgher than that of (100) surface. The CMOS transistor with the silicon nitride gate insulator formed by the microwave-excited plasma and TaN/Ta/TaN metal gate on (110) surface orientation silicon having a higher current drive capability and high integration density is the most practical candidate for lOOnm technology node and beyond.using conventional thermal oxidation processes [2]. We have developed to form high integrity silicon oxide and nitride films on (100) surface at a temperature below 500°C [3] [4], and demonstrated to form high integrity SiOz films on (111) surface, by using microwave-excited high-density plasma featuring very low electron temperature less than 1.OeV [5][6]. Therefore, it is possible to form high quality SiOz and silicon nitride films on any surface orientation by using this technology. Changing wafer surface orientation fiom (100) has an advantage to increase the channel mobility. The purpose of this study is to investigate the scaling limit of nitride films grown by the microwave-excited high-density plasma technique, to demonstrate the surface orientation whose carrier mobility increase, and to present a high quality gate silicon nitride insulator applicable to l O O n m technology node and beyond.

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We have developed a low-resistivity metal gate Metal-Nitride-Semiconductor (MNS) FET technology having conventional plane gate structure featuring fully lowtemperature processing. The gate stack consists of directly grown Silicon Nitride (Si3N4) dielectric using high-density plasma and bcc-phase Tantalum (-l5pQcm) / Tantalum Nitride (bcc-TamaNx) stacked metal gate below l.Oohm/sq. In order to avoid deteriorating the metal gate system, we adopted a low-temperature S/D annealing by Solid Phase Epitaxy (SPE) method.In this paper, we demonstrate an excellent characteristic of Fully-Depleted Silicon-On-Dielectric (FDSOI) metal gate MNSFETs having conventional plane gate structure featuring fully low-temperature proiessing below 450°C.

Aluminum nitride (AlN) thin films were prepared on Inconel 600 superalloy diaphragms by rf magnetron sputtering for the first time to our knowledge. The crystal structure of the AlN films is hexagonal, and the c-axis of the AlN films orients perpendicular to the diaphragm surfaces. The full-width at half-maximum (FWHM) of the X-ray rocking curves of the AlN films is 5.7°, and the piezoelectric constants d33 and d31 are 2.0 and 0.7 pC/N, respectively. We have investigated the influence of the diaphragm structure on the piezoelectric response to pressure of the AlN films. The AlN films sensitively generate electric charges to pressure changes, and the generated charges show an excellent linearity with increasing pressure. The AlN films indicate a high sensitivity of 723 pC/N. The sensitivity of the AlN films agrees with the result calculated using a method in which the electroelastic energy is differentiated from the voltage in AlN films for unimorph circular diaphragms.