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A hydrophilic monodisperse conjugated starburst macromolecule and its excellent function as efficient electron injection layer have been demonstrated.

The n-ZnO/p-Si heterojunction was fabricated by depositing high quality single crystalline aluminium-doped n-type ZnO film on p-type Si using the laser molecular beam epitaxy technique. The heterojunction exhibited a good rectifying behavior. The electrical properties of the heterojunction were investigated by means of temperature dependence current density—voltage measurements. The mechanism of the current transport was proposed based on the band structure of the heterojunction. When the applied bias V is lower than 0.15 V, the current follows the Ohmic behavior. When 0.15 V < V < 0.6 V, the transport property is dominated by diffusion or recombination in the junction space charge region, while at higher voltages (V > 0.6 V), the space charge limited effect becomes the main transport mechanism. The current—voltage characteristic under illumination was also investigated. The photovoltage and the short circuit current density of the heterojunction aproached 270 mV and 2.10 mA/cm2, respectively.

The low temperature phase transformation in the Cu 2 ZnSnS 4 (CZTS) films was investigated by laser annealing and low temperature thermal annealing. The Raman measurements show that a-high-power laser annealing could cause a red shift of the Raman scattering peaks of the kesterite (KS) structure and promotes the formation of the partially disordered kesterite (PD-KS) structure in the CZTS films, and the low-temperature thermal annealing only shifts the Raman scattering peak of KS phase by several wavenumber to low frequency and the broads Raman peaks in the low frequency region. Moreover, the above two processes were reversible. The Raman analyses of the CZTS samples prepared under different process show that the PD-KS structure tends to be found at low temperatures and low sulfur vapor pressures. Our results reveal that the control of the phase structure in CZTS films is feasible by adjusting the preparation process of the films.

Latest innovations in large area web coating technology via plasma enhanced chemical vapor deposition source technology J. Vac. Sci. Technol. A 27, 970 (2009); 10.1116/1.3077287 Structural and optical investigation of plasma deposited silicon carbon alloys: Insights on Si-C bond configuration using spectroscopic ellipsometry Low temperature deposition of nanocrystalline silicon carbide films by plasma enhanced chemical vapor deposition and their structural and optical characterization J. Appl. Phys. 94, 5252 (2003); 10.1063/1.1609631 Plasma-assisted chemical vapor deposition growth of SiC on Si(100): Morphology and electronic structureHydrogenated nanocrystalline silicon carbide ͑nc-SiC:H͒ films have been deposited by using helicon wave plasma enhanced chemical vapor deposition technique at low substrate temperature. The influences of radio frequency ͑rf͒ power and substrate temperature on the properties of the deposited nc-SiC:H films were investigated. It is found that hydrogenated amorphous SiC films were fabricated at a low rf power, while the nc-SiC:H films with a microstructure of SiC nanocrystals embedded in amorphous counterpart could be deposited when the rf power is 400 W or more. The plasma transition from the capacitive dominated discharge to the helicon wave discharge with high plasma intensity influences the film microstructure and surface morphology. The analysis of the films deposited at various substrate temperatures reveals that the onset of SiC crystallization occurs at the substrate temperature as low as 150°C. The low temperature deposition of nc-SiC:H films enables the fabrication of silicon-based thin-film solar cells onto flexible plastic substrates using nc-SiC:H film as a window layer.