Bright blue-violet photoluminescence centered at 428nm was obtained in amorphous Si-in-SiNx thin films prepared in a cyclic growth mode on cool substrates by plasma-enhanced chemical vapor deposition, in which the typical size of the silicon particles has been brought down to ∼1.80nm and the number density amounts to 1.07×1013cm2. A maximum external quantum efficiency over 3.0% was measured in the as-deposited samples. Time-resolved photoluminescence spectra revealed decay times within nanosecond even at room temperature, disclosing a fast recombination dynamics in this amorphous system. The excellent efficiency can be attributed to a better passivation of the silicon particles—hence, the conventional rapid thermal annealing has a negligible effect on the photoluminescence intensity—and also to an improved transparency of the film by cyclic growth. The high-efficiency, tunable wavelength and nanosecond decay time at room temperature, achieved via a low-temperature process without invoking any posttreatment, combine to make the Si-in-SiNx system a promising candidate for light-emitting nanostructures in photonic and optoelectronic applications.

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Phosphorus-doped p-type ZnO thin films are prepared on glass substrates by metalorganic chemical vapor deposition (MOCVD). DEZn, O 2 , and P 2 O 5 powders are used as reactant and dopant sources. The ptype ZnO films are grown at a temperature between 673 K and 723 K. The best p-type sample has a low resistivity of 4.64 V?cm, a hole concentration of 1.61 6 10 18 cm 23 , and a Hall mobility of 0.838 cm 2 ?(V?s) 21 at room temperature. A strong emission peak at 3.354 eV corresponding to neutral acceptor bound excitons is observed at 77 K in the photoluminescence spectra, which further verifies the ptype characteristics of the films.

Unintentionally doped GaSb films grown by Molecular Beam Epitaxy (MBE) on GaAs (001) substrates were annealed under different temperatures and time. It was found that the rapid thermal annealing (RTA) process can improve the optical properties. By changing annealing temperature and time, the optimized annealing temperature and times are found to be 650°C and 30s, respectively. Point defects and dislocations are two major kinds of defect in undoped GaSb thin films grown by MBE on GaAs (001) substrates.