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We investigate the low-temperature doping of phosphorus (P) and boron (B) atoms on hydrogenated amorphous silicon (a-Si:H) films by catalytic doping (Cat-doping). The conductivity of a-Si:H films increases as catalyzer temperature (T cat) increases, and the increase in conductivity is accompanied by a significant reduction in activation energy obtained from the Arrhenius plot of the conductivity. Secondary ion mass spectrometry (SIMS) measurement reveals that Cat-doped P and B atoms exist within ∼10–15 nm from the a-Si:H film surface, indicating that the shallow doping of P and B atoms is realized on a-Si:H films similarly to the case of Cat-doping on crystalline Si (c-Si) wafers. We also confirm no additional film deposition during Cat-doping. These results suggest that decomposed species are effectively doped on a-Si:H films similarly to the case of Cat-doping on c-Si.

The reaction of 3-(2-nitrophenyl)-3-hydroxypropanones with Zn/NH 4 Cl gave the corresponding quinoline N-oxides in 80-90% yields. The reaction initiated the reduction of nitro group to afford the corresponding hydroxylamine, which intramolecularly condensed and followed by dehydration to give quinoline N-oxide. Although treatment of 2-nitrochalcone with Zn/NH 4 Cl in EtOH/H 2 O resulted in the formation of quinoline N-oxide in low yield, the reaction of 2-nitrochalcone with Sn/NH 4 Cl in refluxing EtOH/H 2 O afforded quinoline N-oxide in 80% yield.

A highly effective one-pot synthesis of poly-substituted quinolines from 2-alkynylnitrobenzenes using inexpensive reagents has been developed. Reaction of 2-alkynylnitrobenzenes with Sn/HCl in EtOH resulted in the formation of 2-aminophenyl ketones and subsequently condensed in situ with ketones to form tri-substituted quinolines in 80-97% yields. 93 73 75 84 a) The reaction was carried out in the absence of Na 2 S (8% of 2-phenylindole was obtained as a side product). Simple 2-aminophenylethanones, such as 2-aminoacetophenone and 2-aminobenozophenone, were commercially available; however, few reports on the synthesis of more complicated 2-aminophenyl

We investigate a novel doping method, catalytic impurity doping (Cat-doping), for application to the fabrication of silicon heterojunction (SHJ) solar cells. Thin n- or p-type doped layers can be formed on intrinsic amorphous Si (a-Si) films by exposing P- or B-related radicals generated by the catalytic cracking of phosphine (PH3) or diborane (B2H6) gas molecules. The passivation quality of underlying a-Si films can be maintained both for phosphorus (P) and boron (B) Cat-doping if we carefully choose the appropriate substrate temperature during Cat-doping. We confirm the rectifying and photovoltaic properties of an SHJ solar cell containing a B Cat-doped layer as a p-type a-Si emitter. These findings suggest the applicability of Cat-doping to SHJ solar cells.