Control of the Step Coverage Behavior of Gate a-SiN_x:H

概要

論文の詳細を見る
To overcome the trade-off in the properties of a-SiN_x:H, which is a trade-off between the flat region of gate metal and the step at its side, we have studied the key control factor for determining the step coverage behavior of a-SiN_x:H. To that end, a double rf-biased plasma-enhanced chemical vapor deposition (DRB-PECVD) system which was developed with the aid of Professor Ohmi of Tohoku University, was very helpful. With the DRB-PECVD system, it is possible to control the flux of ions, which plays a major role in determining the film qualities of a-SiN_x:H. With vertical control of the homogeneity of a-SiN_x:H, it was demonstrated that the seep coverage behavior of a-SiN_x:H is determined by the intrinsic film stress which became more compressive(-) with in creasing effect of bombardment by ions extracted and accelerated by the substrate bias rf_2 of the DRB-PECVD system. a-SiN_x:H film can be easily damaged by thermal quenching during the cooling process after the end of deposition as the intrinsic film stress of a-SiN_x:H becomes in creasingly compressive(-). Although the damage can be removed by increasing the thickness of a-SiN_x:H film to greater than 200nm as a gate insulator for a thin film transistor-liquid crystal display (TFT-LCD) panel, it is possible for us to remove the thermal quenching damage on a-SiN_x:H film even when thickness is less than 200 nm.
社団法人応用物理学会の論文
2000-01-15