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Synthesis of a multilayer structure made of superconducting thin films and normal metal or dielectric thin films is an important technology in the superconducting electronics. For example, an S–N–S Josephson junction as a superconducting quantum well device, a superconducting microstrip line and a Josephson transmission line are promising in the future. In this paper, we report on in situ growth of superconductor–dielectric multilayers such as Nb–AlN and NbN–AlN on Si substrate using the off-axial DC magnetron sputtering apparatus and their structural analysis by the Auger electron spectroscopy. We found that Nb, Al and N 2 diffused each other at arbitrary substrate temperatures in the Nb–AlN system. On the other hand, in the NbN–AlN system, Nb and Al slightly diffused when the substrate temperature was low (room temperature), while Nb and Al highly diffused each other when the substrate temperature was high (400°C). NbN–AlN multilayers grown at low substrate temperature were found to be promising in the application such as a superconducting microstrip line. It was also found by the resistivity measurement of AlN thin films that their resistivities were dependent on the input power and partial pressure of N 2 gas during sputtering.

A new source gas mixture of Si(NCO)4 and N(CH3)3 has been investigated for low-temperature chemical vapor deposition of silicon dioxide. Hydrogen-free films have been successfully deposited at 200° C for the first time. Evaluated results are also presented for deposition characteristics and deposited film properties. The breakdown-field strength and low-field resistivity were as high as 5.9 MV/cm and 6×1016 Ωcm, respectively, for the as-deposited film.

A new source gas mixture of Si(NCO)4 and N(CH3)3 has been investigated for low-temperature chemical vapor deposition of silicon dioxide. Hydrogen-free films have been successfully deposited at 200° C for the first time. Evaluated results are also presented for deposition characteristics and deposited film properties. The breakdown-field strength and low-field resistivity were as high as 5.9 MV/cm and 6×1016 Ωcm, respectively, for the as-deposited film.

We propose alkoxyl-silane-isocyanate [(RO) n Si(NCO)4-n ] as a new silicon source material for low-temperature chemical-vapor deposition of silicon dioxide. Detailed deposition characteristics and properties of the deposited film evaluated by auger electron spectroscopy (AES), X-ray photoemission spectroscopy (XPS) and Fourier transform IR (FTIR) are presented for ethoxyl-silane-isocyanate (R=C2H5). The deposition rate took a maximum value of 20 nm/h around 120°C and then decreased gradually with increasing deposition temperature T. The atomic ratio O/Si evaluated by AES was constant and about 2 for T≧200°C. The breakdown-field strength and low-field resistivity were 3.2 MV/cm and 1.3×1015 Ωcm, respectively.