摘要:
In a method of manufacturing semiconductor chips for display, a semiconductor thin film is first formed on an insulating substrate, and then a series of processes including a heat-treatment process for the semiconductor thin film are carried out to form integrated thin film transistors on a sectioned area for one chip. Thereafter, pixel electrodes for one picture (frame) are formed within the sectioned area. During the series of processes, a laser pulse is irradiated onto the sectioned area by one shot to perform a heat treatment on the semiconductor thin film for one chip collectively and simultaneously (i.e., perform a batch heat treatment on the semiconductor thin film). Through the batch heat treatment, the crystallization of the semiconductor thin film is promoted. In addition, after the semiconductor thin film is doped with impurities, the activation of impurities doped in the semiconductor thin film can be performed by the batch heat treatment.
摘要:
A process of forming a silicon thin film includes the steps of: irradiating a pulsed rectangular ultraviolet beam on an amorphous or polycrystalline silicon layer formed on a base body, to thereby form a silicon thin film composed of a group of silicon single crystal grains which are each approximately rectangular-shaped and which are arranged in a grid pattern on the base body. In this process, the moved amount of a ultraviolet beam irradiating position in a period from completion of an irradiation of the rectangular ultraviolet beam to starting of the next irradiation of the rectangular ultraviolet beam is specified at 40 &mgr;m or less, and a ratio of the moved amount to a width of the rectangular ultraviolet beam measured in the movement direction thereof is in a range of 0.1 to 5%. Further, a selected orientation of the silicon single crystal grains to the surface of the base body is approximately the direction.
摘要:
In a method of manufacturing semiconductor chips for display, a semiconductor thin film is first formed on an insulating substrate, and then a series of processes including a heat-treatment process for the semiconductor thin film are carried out to form integrated thin film transistors on a sectioned area for one chip. Thereafter, pixel electrodes for one picture (frame) are formed within the sectioned area. During the series of processes, a laser pulse is irradiated onto the sectioned area by one shot to perform a heat treatment on the semiconductor thin film for one chip collectively and simultaneously (i.e., perform a batch heat treatment on the semiconductor thin film). Through the batch heat treatment, the crystallization of the semiconductor thin film is promoted. In addition, after the semiconductor thin film is doped with impurities, the activation of impurities doped in the semiconductor thin film can be performed by the batch heat treatment.
摘要:
A thin film transistor structure for a liquid crystal display device of the active matrix type, wherein leak current is suppressed to stabilize the threshold voltage and the dispersion in the gate capacitance coupling and the channel length are minimized, is disclosed. The liquid crystal display device comprises a substrate having picture element electrodes arranged in a matrix and switching elements for driving the picture element electrodes, another substrate having opposing electrodes thereon and opposed to the former substrate, and a liquid crystal layer held between the substrates. Each switching element has a multi-gate structure wherein two thin film transistors are connected in series and gate electrodes are electrically connected to each other. Each thin film transistor has a lightly doped drain structure wherein a low density impurity region of the same conductivity type as that of a source region or a drain region is provided at least between the source or drain region and a channel region. At least one of a plurality of such low density impurity regions may have a length or a density different from that of the other low density impurity regions so as to assure sufficient on-current while suppressing the leak current.