Kwan-Wook Jung

High transmittance TFT-LCD panels using low-/spl kappa/ CVD films

Thin-film transistor liquid crystal display (TFT-LCD) panels of a high transmittance structure were fabricated by using a low-/spl kappa/ dielectric film as a passivation layer. The low-dielectric films were successfully deposited and patterned using a conventional plasma-enhanced chemical vapor deposition (PECVD) and plasma-assisted etching techniques. The interface between the a-Si channel and the overlaying passivation was modified by appropriate plasma treatment prior to the low-/spl kappa/ deposition. TFTs having the a-Si:C:O:H passivation showed a transfer characteristics similar to that of conventional TFTs. The high transmittance panel showed brightness approximately 30% higher than that of a standard panel without degrading other display characteristics, such as crosstalk.

Leakage current of amorphous silicon p-i-n diodes made by ion shower doping

In this letter, we report the leakage current of amorphous silicon (a-Si:H) p-i-n photodiodes, of which the p layer is formed by ion shower doping. The ion shower doping technique has an advantage over plasma-enhanced chemical vapor deposition (PECVD) in the fabrication of a large-area amorphous silicon flat-panel detector. The leakage current of the ion shower diodes shows a better uniformity within a 30 cm×40 cm substrate than that of the PECVD diodes. However, it shows a higher leakage current of 2–3 pA/mm2 at −5 V. This high current originates from the high injection current at the p-i junction.

57.2: Fabrication of High‐Transmittance TFT‐LCD Panels Using Low‐k CVD Films

Fabrication of TFT-LCD panels of high resolution and aperture ratio was demonstrated by using a low-k dielectric film as a passivation layer for the first time. The low-k dielectric films were successfully deposited and patterned using a conventional PECVD and plasma-assisted etching techniques, causing no drastic modification to the standard TFT process. Thin film transistors having the a-Si:C:O:H passivation showed a transfer characteristics similar to that of conventional TFTs. The high transmittance panel showed brightness approximately 30% higher than that of a standard panel without degrading other display characteristics, such as cross-talk.