Improved electrical characteristics and reliability of MILC poly-Si TFTs using fluorine-ion implantation

Abstract

In this letter, fluorine-ion (F+) implantation 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 fluorine ions minimize effectively the trap-state density, leading to superior electrical characteristics such as high field-effect mobility, low threshold voltage, low subthreshold slope, and high ON/OFF-current ratio. F+-implanted MILC TFTs also possess high immunity against the hot-carrier stress and, thereby, exhibit better reliability than that of typical MILC TFTs. Moreover, the manufacturing processes are simple (without any additional thermal-annealing step), and compatible with typical MILC poly-Si TFT fabrication processes.