One of the technical trends for a-Si TFTs is their application to large-size, high-pixel-density AM-LCDs such as XGA, EWS and HDTV. For these applications, the TFT performance must be improved and production throughput must be increased to reduce the cost of manufacturing. We will discuss four technologies which will be most important for these purposes. They are: (1) fully self-aligned TFT technology, (1) non-mass-separated ion-doping technology; (3) aluminum-gate-line process technology; and (4) high-deposition-rate a-Si technology. All of them are also suitable for current AM-LCDs such as VGA displays. These technologies are expected to improve TFT device characteristics as well as increase production throughput.