Abstract: A thin film transistor having a vertical channel provided according to the invention comprises a vertical channel 4B having a sideways angular U-shaped or "" -shaped cross-section; source and drain areas 5 formed respectively in two ends of the channel 4B, and a gate electrode 7 surrounding a gate insulating layer 6 formed on upper and outer sides of the channel except for the source and drain areas. Accordingly, the satisfactory channel length in less area can be obtained and the leakage current can be reduced when the transistor is in Off state.

Abstract: A process for producing a thin film transistor suitable to a high integrated static ram (SRAM) or a liquid crystal display, thereby improvements in a leak current and an operating current along with a process for the production of a thin film transistor. The process comprises treating a channel polysilicon layer of a TFT structure with oxygen plasma to eliminate the drawbacks generated in an interface between the channel polysilicon layer and a gate insulating film and in the channel polysilicon layer itself. There may be a reduced leak current when switching off the TFT as well as an increased operating current when switching on the TFT. Accordingly, in accordance with the present invention, the characteristics of TFT is greatly improved.

Abstract: There is provided a TFT having a trench surrounding gate structure that is capable of decreasing the leakage current generated during the Off-State of the TFT by securing enough channel length despite the smallness of the area, increasing the driving current by securing a sufficient cross-sectional area of an inverted channel during the On-State of the TFT, and improving the resolution of the LCD by reducing the space occupied by the TFT in the panel during the manufacturing of the LCD.

Abstract: A method for hydrogenating a thin film transistor, capable of making a sufficient amount of hydrogen penetrate a channel polysilicon of the thin film transistor, thereby reducing the amount of leakage current at a turn-off state of the thin film transistor while increasing the amount of drive current at a turn-on state of the thin film transistor so as to improve the characteristic of the thin film transistor. The method includes the steps of depositing an insulating film as a metal electrode protective film over a thin film transistor, which has been subjected to a patterning for forming metal electrodes, coating a silicon-on-glass film over the insulating film, and depositing another insulating film over the silicon-on-glass film so as to prevent hydrogen contained in the silicon-on-glass film from being externally leaked when the silicon-on-glass film is subsequently subjected to heat treatment.

Abstract: A process for producing a thin film transistor suitable to a high integrated static ram (SRAM) or a liquid crystal display, thereby improvements in a leak current and an operating current along with a process for the production of a thin film transistor.The process comprises a step of forming a SOG film in a predetermined thickness on the entire upper surface of a TFT structure and subsequently treating the SOG film with O.sub.2 plasma to increase the hydrogen content therein, a step of depositing an insulating film on the SOG film to prevent the hydrogen of SOG film from escaping therefrom and thereafter, applying heat treatment to the SOG film to infiltrating the hydrogen of the SOG film into a channel formed in a polysilicon layer in the TFT structure, and a step of removing the insulating film and the SOG film.There may be reduced a leak current when switching off the TFT as well as increased an operating current when switching on the TFT.