High-quanlity l ow-temperature gate oxide for poly-Si TFTs

摘要

There is considerable interest in low temperature oxide for poly-Si TFTs. We compared the chemical and electrical properties of various low temperature oxides. It was found that the amount of Si-OH bonds in the oxides is closely related to fixed oxide charge density. Among these oxides, remote-plasmna enhanced CVD oxide showed the lowest Si-OH bond density. Morecover, by increasing the flow rations of O_2/SiH_4. High quality oxide with low density of Si-OH (1x10~(14) cm~(-2), low density of fixed oxide charge (7.8x10~(11) cm ~(-2)), and low interface trap density (6x10~(10)cm~(-2)) was obtained. These values are sufficient for gate oxides in poly-Si TFTs.