of current flowing to an el device as maintaining high speed switching operation as it is by forming a high resistance offset region 530 on which impurities are partially doped between the multiple gates 541 and 545 of the driving transistor therefore a high speed display device capable of emitting light to a desired proper luminance according to the doping state of the offset region 530 namely length of offset ldoff of a portion 531 in the offset region 530 on which impurities are not doped can be realized fig6 a and fig6 b illustrate plane and cross sectional structures of driving transistor in an organic light emitting diode according to fourth preferred embodiment of the present invention wherein fig6 b is illustrates a cross sectional view taken along a line 6 b u2013 6 b u2032 of fig6 a the driving transistor according to the fourth preferred embodiment of the present invention controls the amount of current flowing through an el device by forming multiple gates as a gate electrode and changing width of an offset region that is a high resistance region between the multiple gates referring to fig6 a and fig6 b the driving transistor according to the fourth preferred embodiment in which width of the offset region is changed has a structure almost similar to the driving transistor according to the first preferred embodiment illustrated in fig3.