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We have developed a new controllable method of selective and nonselective deposition of high quality aluminum by low‐pressure chemical vapor deposition using dimethylaluminum hydride with hydrogen. At first, silicon dioxide via holes on silicon substrate were selectively filled with aluminum by thermal decomposition. Then, adding the plasma excitation for 1 min, the aluminum film began to deposit nonselectively on the silicon dioxide as well as the selectively deposited aluminum. Silicon dioxide via holes were completely planarized by the selective and nonselective deposition. The single‐crystal structure of aluminum deposited selectively on silicon was observed with a new scanning microreflection high‐energy electron diffraction microscope.

A selective method of depositing aluminum onto silicon was developed using trimethylaluminum and hydrogen as source gases. Trimethylaluminum was selectively decomposed into excited species through the well controlled radio frequency (13.56 MHz) excited hydrogen plasma of 0.03–0.06 W/cm3. Excited species were reacted on the silicon surface to produce aluminum without carbon incorporation at 230–260 °C. The thermally oxidized silicon dioxide line and space pattern and contact windows were successfully filled with selectively deposited 3000‐A‐thick aluminum.

We have observed the minority‐charge signal transferred by surface acoustic waves (SAW) on a monolithic MIS structure. In the Al/ZnO/SiO2/p‐Si system, we have made new improvements on the configuration of input and output gates and the channel‐stop bias ring along the transfer path, and on the method to prepare the deep‐depletion mode by applying the pulse bias at the transfer channel. This type of charge‐transfer device by SAW (monolithic SAW‐CTD) seems to have some advantages compared with the separated‐medium type so far examined.

We report on a new surface‐acoustic‐wave (SAW) amplifier and generator on a monolithic MIS structure with a uniform pump electrode. The gain for the forward SAW and the generation of the backward SAW have been observed in an Al/ZnO/SiO2/Si structure. Using the same structure, we observed for the first time the parametric generation of SAW of 222 MHz by the uniform pumping, even if there is no signal input.

Single‐crystal AlN layers have been grown on Si substrates at ∼1200 °C using metalorganic chemical vapor deposition. The metal/AlN/Si MIS structures have been investigated by the MIS conductance method. It was found that the interface‐state density Nss and electron capture cross section σn in the depletion region are of the order of 1011 eV−1 cm−2 and 10−17 cm, respectively.

Experiments on a two‐dimensional acoustic distributed feedback (ADFB) laser are described. A set of distributed Bragg reflectors (DBR’s) were formed on a GaAs crystal which was optically pumped at liquid‐nitrogen temperature and an surface acoustic wave (SAW) at a frequency around 1.2 GHz was injected into the planar region between the DBR’s. We observed the oscillation of the two‐dimensional ADFB modes. The SAW power, needed for the onset of the oscillation of the modes, was about 5 mW under the present experimental condition. Some discussions on its applications are briefly described.