A poly-Si TFT fabricated by excimer laser recrystallization onfloating active structure

This letter reports a. new excimer laser annealing (ELA) method to produce large polycrystalline silicon (poly-Si) lateral grains exceeding 4 μm. A selectively floating amorphous silicon (a-Si) flint with a 50 nm-thick air-gap was irradiated by a single-pulse XeCl excimer laser and uniform lateral grains were grown due to the lateral thermal gradient caused by the low thermal conductivity of the air. A poly-Si thin-film transistor (TFT) with two high-quality 4.6 μm-long lateral grains was fabricated by employing the proposed ELA and high field-effect mobility of 331 cm²/Vsec was obtained due to. the high-quality grain structure     

Reliability-based design optimization of a pick-up device of a manganese nodule pilot mining robot using the Coandă effect

Design of a pick-up device using the Coandă effect in a deep-sea mining robot is vital to develop a reliable and sustainable deep-sea mining system. One of the crucial performance metrics of this device is the collection efficiency since it affects the mining efficiency of the entire system. However, the collection efficiency is significantly affected by the uncertainties of shape, size and mass of manganese nodules on the seabed. In this study, reliability-based design optimization (RBDO) was performed to improve the reliability of the collection efficiency of the pick-up device under these environmental uncertainties. First, a computational model based on the Coandă effect that predicts the collection efficiency of the pick-up device was developed. Next, RBDO based on the Akaike information criterion method was employed to design the pick-up device by using this model. The results demonstrated that the proposed design methodology significantly improved the design of the pick-up device for the pilot mining robot.

     

Poly-Si TFT fabricated by laser-induced in-situ fluorinepassivation and laser doping

A new poly-Si TFT has been fabricated by employing laser-induced in-situ fluorine passivation and a laser-doping method. With only one excimer laser annealing, we have successfully fabricated the device using one step to crystallize, passivate and dope simultaneously. Although no additional plasma post-passivation was performed, the on-state and the off-state leakage properties of TFTs with fluorine passivation were improved compared with those without fluorine passivation. The device with in-situ fluorine passivation has the maximum transconductance of 13.3 μA/V for a C₂F₆ flow rate of 100 sccm, whilst that for a device without fluorine passivation is 8.4 μA/V. The device reliability under electrical stress was remarkably improved in the in-situ fluorine-passivated devices due to the fluorine passivation of trap states in the poly-Si channel and at the SiO₂/poly-Si interface