Alternating magnetic field-assisted crystallization of Si films without metal catalyst

Low-temperature crystallization of amorphous Si (a-Si) has been investigated by employing alternating magnetic field. Even at 430 °C, with the aid of magnetic field that was applied in the perpendicular direction to a-Si films without any metal catalyst and electrical contact, crystalline structure of the Si films was changed from amorphous to polycrystalline. The evaluated crystal fraction of the polycrystalline Si (poly-Si) was about 90% and twin boundaries were observed in the poly-Si films. Thin-film transistors using poly-Si fabricated by applying the alternating magnetic field showed superior drain current uniformity of below ±7% due to the smooth grain boundary without protrusion. The method using alternating magnetic field represents an excellent approach to the fabrication of uniform switching electronics for flat panel displays.