Conditions for producing high-quality localized Ge-on-insulator film stacks on Si substrates by liquid phase epitaxy are discussed. In particular, we have found that the resulting Ge crystal planes have a tendency to exhibit a twist about the long axis of the crystal. If the wafer is heated much above the Ge melting temperature, this twist can be quite large (∼10°). The twist can be minimized by heating to just above the melting temperature and by using thicker Ge films. In spite of this twist, the Ge regions on top of the insulating Si3N4 are observed to be free of dislocations and stacking faults.

High-quality epitaxial Ge films were grown on GaAs substrates by ultrahigh vacuum chemical vapor deposition. High crystallinity and smooth surface were observed for these films by x-ray diffraction, transmission electron microscopy, and atomic force microscopy. Direct band gap emission (1550 nm) from this structure was detected by photoluminescence. Valence band offset of 0.16 eV at the Ge/GaAs interface was measured by x-ray photoelectron spectroscopy. N-type arsenic self-doping of 1018/cm−3 in the grown Ge layers was determined using electrochemical capacitance voltage measurement. This structure can be used to fabricate p-channel metal-oxide-semiconductor field-effect transistor for the integration of Ge p-channel device with GaAs n-channel electronic device.

High quality GaN film was successfully grown on 150 mm Si ͑111͒ substrate by metal-organic vapor phase epitaxy method using AlN multilayer combined with graded AlGaN layer as buffer. The buffer layer structure, film quality, and film thickness are critical for the growth of the crack-free GaN film on Si ͑111͒ substrate. Using multilayer AlN films grown at different temperatures combined with graded Al 1−x Ga x N film as the buffer, the tensile stress on the buffer layer was reduced and the compressive stress on the GaN film was increased. As a result, high quality 0.5 m crack-free GaN epitaxial layer was successfully grown on 6 in. Si substrate.

X-ray photoelectron spectroscopy has been used to study residual film formation on silicon exposed to an oxygen-containing CF4 plasma. Experimental results indicate that the plasma reaction produces a surface phase SixOFy, which varies in thickness with the O content of the plasma. Film thickness is shown to correlate with the previously observed etch rate dependence on oxygen content.

A Pb5Ge3O11 metal–ferroelectric–metal–oxide–silicon memory transistor has been fabricated. The device showed a memory window of about 2 V. The memory window was almost saturated at the operation voltage of 2 V. The “off” state drain current (ID) at VD of 0.1 V and VG of 0.5 V is about 1×10−8 A. The “on” state drain current (ID) at VD of 0.1 V and VG of 0.5 V is about 1×10−6 A, which is 100 times high than that of off state.