A new separation technique called stripping crystallization (SC) is applied for purification of a mesitylene/pseudoumene mixture. SC combines distillation and crystallization to produce pure crystals due to the three-phase equilibrium. The experiments demonstrate that a batch SC operation can purify pseudoumene from 85 % to 95 % for the pseudoumene-rich mixture with a recovery rate of 51 % while it can only purify mesitylene from 85 % to 88 % for the mesitylenerich mixture with a recovery rate of 34 %. Compared to azeotropic distillation, SC is a clean separation technology as no chemicals are added. SC can be continued until the liquid phase is completely eliminated and only pure crystals remain in the feed. Compared to conventional crystallization, filtration or centrifugation is not needed to separate the solid crystals from the mother liquor since no mother liquor is present together with the crystals. In addition, crystal washing is not required since no impurities adhere to the crystal surfaces at the end of operation.

Ni-metal-induced crystallization (MIC) of amorphous Si (a-Si) has been employed to fabricate low-temperature polycrystalline silicon thin-film transistors (TFTs). However, the Ni residues degrade the device performance. In this study, a new method for manufacturing MIC-TFTs using drive-in Ni-induced crystallization with a chemical oxide layer (DICC) is proposed. Compared with that of MIC-TFTs, the on/off current ratio (I on /I off ) of DICCTFTs was increased by a factor of 9.7 from 9.21 9 10 4 to 8.94 9 10 5 . The leakage current (I off ) of DICC-TFTs was 4.06 pA/lm, which was much lower than that of the MIC-TFTs (19.20 pA/lm). DICC-TFTs also possess high immunity against hot-carrier stress and thereby exhibit good reliability.

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In this study, CF 4 -plasma was employed to improve the electrical performance of metal-induced lateral crystallization (MILC) polycrystalline silicon thin film transistors (poly-Si TFTs). It was found that CF 4 -plasma minimize effectively the trap-state density during etching surface of channel, leading to superior electrical characteristics such as high field-effect mobility, low threshold voltage, low subthreshold slope, low leakage current, and high on/off current ratio.