Abstract: A thin film transistor (TFT) including a polycrystalline active layer and a method for making the same are disclosed. An amorphous silicon layer is deposited on a substrate and is crystallized by using MILC (metal induced lateral crystallization) to provide a poly-silicon active layer of the TFT. Specifically, the amorphous silicon layer is poly-crystallized during a thermal treatment of the active layer. The thermal treatment causes the MILC of the active layer propagating from portions of the source and the drain regions on which MILC source metal is formed through the contact holes of the TFT.

Abstract: The present invention relates to a method for crystallizing the active layer of a thin film transistor utilizing crystal filtering technique. According to the conventional metal induced lateral crystallization (MILC) method, amorphous silicon layer can be crystallized into poly-crystal silicon layer. According the crystal filtering technique of the present invention, amorphous silicon layer can be single-crystallized by filtering a single crystal component from the poly-crystal region being crystallized by MILC. The TFT fabricated including an active layer crystallized according to the present method has significantly improved electrical characteristics such as electron mobility and leakage current as compared to the TFT including a poly-crystal silicon active layer made by conventional methods. The invention also provides various TFT fabrication methods applying the crystal filtering technique.

Abstract: A thin film transistor (TFT) including a polycrystalline active layer and a method for making the same are disclosed. An amorphous silicon layer is deposited on a substrate and is crystallized by using MJLC (metal induced lateral crystallization) to provide a poly-silicon active layer of the TFT. Specifically, the amorphous silicon layer is poly-crystallized during a thermal treatment of the active layer. The thermal treatment causes the MILC of the active layer propagating from portions of the source and the drain regions on which MILC source metal is formed through the contact holes of the TFT.

Abstract: A method for fabricating a TFT including a crystalline silicon active layer is disclosed, in which the metal which induced the crystallization of the active layer is offset from a gate electrode utilizing a mask used to form a lightly doped drain (LDD) region or an offset junction region in the active layer. The TFT includes a silicon active layer crystallized by crystallization inducing metal and a gate electrode, and has an LDD region or an offset junction region formed in the vicinity of the channel region. The method for fabricating the TFT forms a metal offset region without using an additional photoresist forming process, and forms a LDD region by conducting a low density doping in the metal offset region. As a result, a transistor made according to the present invention has low leakage current in its off-state, and has stable electrical characteristics in its on-state.

Abstract: A thin film transistor (TFT) including a polycrystalline active layer and a method for making the same are disclosed. An amorphous silicon layer is deposited on a substrate and is crystallized by using MILC (metal induced lateral crystallization) to provide a poly-silicon active layer of the TFT. Specifically, the amorphous silicon layer is poly-crystallized during a thermal treatment of the active layer. The thermal treatment causes the MILC of the active layer propagating from portions of the source and the drain regions on which MILC source metal is formed through the contact holes of the TFT. The TFT fabricated according to the present invention has improved electrical characteristics such as electron mobility and leakage current. The present invention further improves the performance of the TFT by making the MILC boundary is formed outside of the channel region so that the MILC boundary may not adversely affect the operation of the TFT.

Abstract: A method for fabricating a TFT including a crystalline silicon active layer is disclosed, in which the metal which induced the crystallization of the active layer is offset from a gate electrode utilizing a mask used to form a lightly doped drain (LDD) region or an offset junction region in the active layer. The TFT includes a silicon active layer crystallized by crystallization inducing metal and a gate electrode, and has an LDD region or an offset junction region formed in the vicinity of the channel region. The method for fabricating the TFT forms a metal offset region without using an additional photoresist forming process, and forms a LDD region by conducting a low density doping in the metal offset region. As a result, a transistor made according to the present invention has low leakage current in its off-state, and has stable electrical characteristics in its on-state.

Abstract: The present invention relates to a method of crystallizing an amorphous silicon thin film by thermal annealing the amorphous silicon thin film vapor deposited on a substrate in order to form a polycrystalline silicon thin film, and a semiconductor device fabricated by the method. According to the present invention, it is constructed such that a light-absorbing layer having absorbance of light much higher than that of the substrate or the amorphous silicon thin film is formed around the amorphous silicon thin film and is heated by a lamp when crystallizing the amorphous silicon thin film vapor deposited on the substrate by rapid annealing. Therefore, the temperature of the amorphous silicon thin film can be raised while restraining the increase in temperature of the substrate to the utmost. Accordingly, the amorphous silicon thin film can be crystallized without deformation of the substrate.

Abstract: The present invention relates to a method for crystallizing the active layer of a thin film transistor utilizing crystal filtering technique. According to the conventional metal induced lateral crystallization (MILC) method, amorphous silicon layer can be crystallized into poly-crystal silicon layer. According the crystal filtering technique of the present invention, amorphous silicon layer can be single-crystallized by filtering a single crystal component from the poly-crystal region being crystallized by MILC. The TFT fabricated including an active layer crystallized according to the present method has significantly improved electrical characteristics such as electron mobility and leakage current as compared to the TFT including a poly-crystal silicon active layer made by conventional methods. The invention also provides various TFT fabrication methods applying the crystal filtering technique.