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In this paper, NH3 plasma directly applied to the surface of poly-Si channel is studied for the development of high-performance low-temperature polycrystalline-silicon thin-film transistors (LTPS-TFTs) with HfO2 high- \kappa gate dielectric. The reduction of threshold voltage from 1.52 to 0.62 V, the decrease of subthreshold swing from 227 to 151 mV/decade, and the enhancement of field effect mobility \mu _{\mathrm {FE}} from 31 to 65 cm ^{\mathrm {\mathbf {2}}}$ /Vs are observed after NH3 plasma surface treatment. It can be attributed to the NH3 plasma surface treatment enabling defect passivation and plasma-induced interfacial layer (PIL) growth. To decouple the impacts of defect passivation and PIL growth, the device without PIL is also fabricated. This paper demonstrates the important impacts of NH3 plasma surface treatment on the improvement of electrical characteristics of LTPS-TFTs. [ABSTRACT FROM PUBLISHER]

In this paper, the opposite impacts of N2O plasma surface treatment on the n- and p-channel low-temperature poly-Si thin-film transistors (LTPS-TFTs) with HfO2 gate dielectric are investigated. Significant performance improvement of n-channel LTPS-TFT by N2O plasma surface treatment is observed, including threshold voltage reduction \Delta V\mathrm {\mathbf {TH}}\sim -0.57 V, 1.55× higher transconductance G\mathit {m} , and 1.82× higher driving current I{\rm{drv}} . However, p-channel LTPS-TFT shows serious performance degradation after N2O plasma surface treatment, including threshold voltage increase \Delta V\mathrm {\mathbf {TH}}~\sim -0.99 V, transconductance G\mathit {m} reduction, and driving current I\mathrm {\mathbf {drv}} degradation. The difference of the two mechanisms of N2O plasma surface treatment, namely, plasma induced interfacial layer (PIL) growth effect and trap passivation effect on poly-Si, is elaborated by a process of the PIL removal after the PIL growth. As a result, the trap passivation effect benefits both n- and p-channel LTPS-TFTs. The PIL growth effect shows the opposite impacts on the n- and p-channel LTPS-TFTs, that benefits n-channel LTPS-TFT and degrades p-channel LTPS-TFT seriously. Therefore, the negative impacts of N2O plasma surface treatment on the p-channel LTPS-TFTs can be eliminated by a PIL removal step in the process. These results would be critical for the applications of system-on-panel and 3-D integrated circuit. [ABSTRACT FROM PUBLISHER]

Identification and characterization of materials used in cultural heritage and conservation can provide important information for dating, authentication and deteriorating situation in general. How to extract useful information from these materials in-situ is one of the main concerns. Application of mobile Raman spectroscopy for this purpose has great attentions for scientists and conservators. The present paper aims to investigate the mobile Raman spectroscopy in studying the effect of UV light on the deterioration of silk, seal ink and Chinese traditional colorants such as kermes, vermillion and zhubiao, which is commonly appeared on painted works of art, and the silk sample is also often used as an consolidant for repairing destroyed textile objects. Spectra were recorded from predefined regions on the samples before and after ultraviolet radiation with 360 nm wavelength and 0.68 W x m(-2) intensity. The result revealed obvious effects of ultraviolet radiation on the materials simulated in this research. The original kind of seal ink has been clearly identified. The changes in spectra of all samples with and without UV radiation were further distinguished and studied. The result will assist for scientists and conservators to determine the safe treatments and suitable environmental condition for storage, display and transport. The result will also help for studying mechanism of deterioration of museum objects influenced by environmental factors. The mobile Raman spectroscopy showed a suitable and convenient means for in-situ non-destructive detection and study of deterioration in practical conditions.