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Al:SiO cermet thin films were synthesized by thermal coevaporation. Physical properties of these thin films were characterized by scanning electron microscope, transmission electron microscope, x-ray photoelectron spectroscopy, current–voltage, and optical absorption measurement. The data show that the Al:SiO films consist of crystalline Al islands embedded in an amorphous network of mixed Si, SiO2, and Al2O3 as Al weight percentage exceeds ∼50%. It is found that the size of Al islands increases with increasing Al concentration, which leads to a dramatic reduction in resisitivity and optical transmittance. A multilayered SiO:Al/Al/LiF structure has been utilized as a cathode for top-emission organic light-emitting diode (TOLED). A model based on Fabry–Perot cavity has been used to simulate the TOLED light emission spectra. The results indicate that Al:SiO films can also be used as a semitransparent mirror for a half-wavelength planar microcavity light-emitting diode.

The effect of doped buffer layers at the anode/organic interface in small molecule organic light-emitting diodes was investigated. Appropriate doping of N,N′-bis(1-naphthyl)-N,N′-diphenyl-1,1′-biphenyl-4,4′-diamine (NPB) and Cu-phthalacyanine (CuPc) layers using LiF or C60 molecules leads to improved interfacial morphology and thermal stability for both standard indium tin oxide or metals anodes, such as Au and Ag. Graded interfaces remain stable at temperatures well above the hole transport layer (i.e., NPB) glass transition temperature.

A computer simulation model of amorphous silicon solar cells using a Scharfetter and Gummel solution of Poisson’s equation and Taylor and Simmons occupancy statistics for the dangling bond gap states (D states), has been developed. With a suitable choice of parameters, the numerical results for solar cell collection efficiency and dark and illuminated I‐V characteristics agree well with experimental values. The model has been used specifically to study the influence of interface states at the TCO‐p (transparent conductive oxide), p‐i, i‐n, and n‐metal interfaces and to explain the beneficial role of a graded‐band‐gap layer at the p‐i interface.

Amorphous silicon alloyed p‐i‐n solar cells have been fabricated using a separate chamber photochemical vapor deposition system. The photocharacteristics of such cells have been modestly improved by the addition of a carbon‐alloyed graded‐band‐gap layer at the p(a‐SiC:H)/i(a‐Si:H) heterointerface. The best efficiency obtained for a glass/TCO (transparent conductive oxide)/p(a‐SiC:H)/i(a‐Si:H)/n(μc‐Si:H)/metal structure of this type was 11.2% for a 3×3 mm2 cell; other parameters were Voc=0.882 V, Isc=18.05 mA/cm2, and a fill factor (FF) of 0.702.

Hydrogenated amorphous silicon solar cells were fabricated by photochemical vapor deposition. A three‐separate‐chamber system was newly developed to reduce the contamination of the dopant elements as well as oxygen or water originated by the loading and unloading procedure. Wide optical band‐gap hydrogenated amorphous silicon carbide was prepared using acetylene (C2H2) for the p layer. The deposition conditions for each layer were optimized and the highest‐energy conversion efficiency of 9.64% was obtained. This high conversion efficiency was mainly attributed to the large short‐circuit current which indicated that the quality of the i layer is reasonably good.