The solid phase crystallization of amorphized Si films on quartz substances is studied by means of the transmission electron microscope observation of grain growth. The amorphous Si films are prepared by Si ion implantation into polycrystalline Si films deposited by low-pressure chemical vapor deposition. It has been found that the twin formation in grains at the early stage of the crystallization accelerates the growth rate preferentially in a 〈112〉 direction. During the twin growth about a given 〈112〉 direction, other twins also grow from the twin boundary dendritically in some other 〈112〉 directions, leading to the formation of a large grain of dendritic structure.

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The ultimate limit of electron beam lithography in practical samples, e.g., thick PMMA on bulk Si substrate, was investigated in both experiment and theory. For this, the nanometer electron beam lithography system (NSF-1) was used to perform nanometer structure patterning. Monte Carlo calculation with secondary electron generation included was done to simulate the experiment. Eight nanometer wide lines with 100 nm period were delineated in 230 nm thick PMMA on a bulk Si, probably attaining the ultimate limit of electron beam fabrication. This has also been supported by evaluation based on the Monte Carlo simulation.

The bulk lifetime of minority carriers, b , in germanium (Ge) is one of the most important material parameters in the design and fabrication of Gebased solar cells. Surface passivation of Ge substrates is indispensable to the accurate evaluation of b . We have found that a newly developed wet chemical treatment, quinhydrone-methanol (Q/M) solution treatment, effectively passivates Ge surfaces, achieving a surface recombination velocity (S) of less than 20 cm/s. It has been clarified that oxide layers containing the molecules from the Q/M solution were formed on the Ge surfaces treated with the Q/M solution. Ge dangling bonds (DBs) are thought to be terminated by these oxygen related molecules. Band bending in the Ge substrates induced by the oxide layers adsorbed on the Q/M-treated Ge surface can contribute to the reduction in S. We also briefly discuss the properties of a recombination center found in the bulk of highly resistive Ge substrates. #

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